Patent Description:
Instruments currently exist on the market in the U. that detect the growth of a microorganism in a biological sample. One such instrument is the BACT/ALERT® VIRTUO® microbial test instrument sold by bioMérieux, Inc. The instrument can receive a specimen container such as a blood culture bottle containing a blood sample from an animal or human patient. The instrument incubates the bottle and periodically during incubation an optical detection unit in the incubator analyzes a colorimetric sensor incorporated into the bottle to detect whether microbial growth has occurred within the bottle. The optical detection unit, bottles, and sensors are described in the patent literature. See, <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>.

Other prior art of interest relating generally to the detection of microorganisms in a biological sample include the following patents: <CIT>, <CIT>; <CIT>, <CIT>, <CIT>, <CIT>, <CIT>; <CIT>; <CIT>; and <CIT>.

Other test instruments use other sensors and microbial detection devices, such as infrared sensors and fluorescent indicators for samples in specimen containers. For example, detection can be accomplished using intrinsic fluorescence of the microorganism, and/or detection of changes in the optical scattering of the media. See, e.g., <CIT>.

Yet other detection instruments detect or sense the generation of volatile organic compounds in the media or headspace of the container. Other documents, such as <CIT>, describe examples of methods and systems adapted to pick and place a specimen container from and to a sample rack in systems for processing biological liquids.

Certain events during testing in a detection instrument can cause a false positive for a test result of a sample in a specimen container. A false positive is defined as an event where the detection system incorrectly identifies a test result as positive.

An embodiment of the present invention is directed to a method for selecting an empty cell to place an incoming specimen container in a test instrument according to claim <NUM>.

Another embodiment of the present invention is directed to a test system for evaluating samples according to claim <NUM>.

Another embodiment of the present invention is directed to a computer program according to claim <NUM>.

Further features, advantages and details of the present invention will be appreciated by those of ordinary skill in the art from a reading of the figures and the detailed description of the preferred embodiments that follow, such description being merely illustrative of the present invention.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which some embodiments of the invention are shown. It will be appreciated that although discussed with respect to a certain embodiment, features or operation of one embodiment can apply to others. The terms "Fig." and "FIG. " may be used interchangeably with the word "Figure" as abbreviations thereof in the specification and drawings.

In the drawings, the thickness of lines, layers, features, components and/or regions may be exaggerated for clarity. In addition, the sequence of operations (or steps) is not limited to the order presented in the claims unless specifically indicated otherwise.

While the term "comprising" may be used herein, it should be understood that the objects referred to as "comprising" elements may also "consist of" or "consist essentially of" the elements. As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean "between about X and about Y. " As used herein, phrases such as "from about X to Y" mean "from about X to about Y.

The term "automatically" means that the operation can be substantially, typically entirely, carried out without human or manual input, and is typically programmatically directed or carried out. The term "electronically" includes both wireless and wired connections between components. The term "about" means that the recited numerical value can vary by between about +/-<NUM>%.

The terms "circuit" and "module" are used interchangeably and refer to an entirely software embodiment or an embodiment combining software and hardware aspects, features and/or components (including, for example, at least one processor and software associated therewith embedded therein and/or executable by and/or one or more Application Specific Integrated Circuits (ASICs), for programmatically directing and/or performing certain described actions or method steps). The circuit or module can reside in one location or multiple locations, it may be integrated into one component or may be distributed, e.g., the circuit or module may reside entirely in the test instrument, partially in the test instrument or communicate with the test instrument but reside totally in a remote location (i.e., server) away from the instrument such as in a Laboratory Information System (LIS) or in a cloud based server system.

Generally stated, automated systems/instruments and methods for non-invasive detection of the presence of a microbial agent (e.g., a microorganism) in a test sample contained within a specimen container, e.g., a culture bottle, are described herein. The systems and methods can select which of the empty cells to load a newly intaken specimen container to reduce a likelihood of inducing a false positive. Thus, the systems/methods can electronically exclude empty cells from being loaded with a newly intaken specimen container if those empty cells are identified as having an increased risk for causing a false positive in the newly intaken specimen container and/or to specimen containers in occupied cells.

One embodiment of the automated system or instrument is described herein in conjunction with <FIG>, <FIG>, <FIG>, <FIG> and <FIG>. In order to better appreciate how the illustrated embodiment of the test system can operate, this specification may describe the automated test system in the context of a particular detection instrument (a blood culture instrument) and specimen container (a blood culture bottle). However, persons skilled in the art will readily appreciate that the test system can be practiced in other embodiments, that variations from the specific embodiments disclosed herein can be arrived at to suit particular implementations, and that therefore the present description is provided by way of illustration and not limitation.

Referring now to <FIG>, <FIG>, an automated test system <NUM> comprises a housing <NUM> and is configured with a holding structure <NUM> comprising a plurality of stacked cells <NUM> for holding specimen containers <NUM> for automated detection of a microbial agent (e.g., a microorganism) that may be present in a test sample or specimen sample held in a respective specimen container <NUM>.

In general, any known test sample (e.g., a biological or even environmental sample) can be tested. For example, the test sample can be a clinical or non-clinical sample suspected of containing one or more microbial agents. Clinical samples, such as a bodily fluid, include, but are not limited to, blood, serum, plasma, blood fractions, joint fluid, urine, semen, saliva, feces, cerebrospinal fluid, gastric contents, vaginal secretions, tissue homogenates, bone marrow aspirates, bone homogenates, sputum, aspirates, swabs and swab rinsates, other body fluids, and the like. Non-clinical samples that may be tested include, but are not limited to, foodstuffs, beverages, pharmaceuticals, cosmetics, water (e.g., drinking water, non-potable water, and waste water), seawater ballasts, air, soil, sewage, plant material (e.g., seeds, leaves, stems, roots, flowers, fruit), blood products (e.g., platelets, serum, plasma, white blood cell fractions, etc.), donor organ or tissue samples, biowarfare samples, and the like. In one embodiment, the biological sample tested is a blood sample.

As shown, for example, in <FIG> and <FIG>, the automated test system <NUM> comprises an externally accessible container intake mechanism <NUM> (<FIG>) and one or more internal automated loader mechanisms <NUM> (<FIG>) or <NUM> (<FIG>) for loading a specimen container <NUM> into a desired open cell of the holding structure <NUM>. As shown, the housing <NUM> comprises back and front panels 104A and 104B, opposing side panels (e.g., left-side and right-side panels) 106A and 106B, a top or roof panel 108A and a bottom or floor panel 108B, which form an enclosure, enclosing an interior chamber <NUM> (see, e.g., <FIG>) of the detection system <NUM>.

In some embodiments, the interior chamber <NUM> is a climate-controlled chamber (e.g., a temperature-controlled incubation chamber wherein the temperature is maintained at about <NUM>° Celsius ("C") to promote or enhance microbial growth. As shown in <FIG>, the housing <NUM> also may include a first port or container entrance location <NUM>, a second port or misread/error location <NUM>, a third port or positive container exit location <NUM>, a lower access panel <NUM> (<FIG>) or drawer <NUM> (<FIG>), and/or a user interface display <NUM> (<FIG>).

The lower access panel <NUM> or drawer <NUM> may include a handle <NUM>. Also as shown in <FIG>, the housing <NUM> may also comprise upper and lower sections <NUM> and <NUM>, optionally each comprising an operable door (i.e., upper and lower doors) <NUM> and <NUM> (see, e.g., <FIG>). The upper door <NUM> and lower door <NUM> are operable to allow access to the interior chamber <NUM> of the detection system <NUM>. However, as one of skill in the art would appreciate other design configurations are possible. For example, in another possible embodiment, the entire front panel 104B may comprise a single operable door (not shown).

As shown for example in <FIG>, the lower section <NUM> may have a larger profile or footprint than the upper section <NUM>. In accordance with this embodiment the housing of the larger lower section <NUM> forms a shelf <NUM> on a top surface of the lower section <NUM> and adjacent to or in front of the upper section <NUM>. This shelf <NUM> may provide a user workstation and/or workflow access points to the detection system <NUM>. Furthermore, the shelf <NUM> may comprise an automated container intake mechanism <NUM> such as a conveyor. The shelf <NUM> may further provide access locations for the first port or container entrance location <NUM>, the second port or misread/error location <NUM>, and the third port or positive container exit location <NUM>.

As shown for example in <FIG> and <FIG>, the automated intake mechanism <NUM> may comprise a container loading station or area <NUM>, a transport mechanism <NUM> and a first port or container entrance location <NUM>. In operation, a user or technician can place one or more specimen containers <NUM> (see, e.g., <FIG> and <FIG>) at the container loading station or area <NUM>. A transport mechanism <NUM>, for example, a conveyor belt <NUM>, will transport the specimen container <NUM> to the first port or container entrance location <NUM>, and in some designs subsequently through the entrance location <NUM> and into the test system <NUM>, thereby intaking the container <NUM> into the test system <NUM>. The sample in the container <NUM> at intake can be at a temperature that is less than the temperature in the interior chamber <NUM> and may be chilled, pre-heated or at an ambient temperature.

The test system <NUM> may also comprise an automated internal loader or loading mechanism <NUM> (<FIG>) or <NUM> (<FIG>) that is in the interior chamber <NUM> for moving the specimen containers <NUM> within the housing <NUM>. For example, the internal loading mechanism <NUM> (<FIG>), <NUM> (<FIG>) can transfer the specimen container <NUM> from an entrance location or port <NUM> (see, e.g., <FIG>), into the interior chamber <NUM> of the detection system <NUM>, and place the container <NUM> into one of the cells <NUM> provided by the holding structure <NUM> which can include a plurality of stacked racks 600r. The transfer mechanism <NUM> (<FIG>) or <NUM> (<FIG>) may also be used to rearrange, transfer or otherwise manage specimen containers <NUM> within the system. For example, in one embodiment, the transfer mechanism <NUM>, <NUM> can be used to transfer a specimen container <NUM>, detected as positive for microbial growth (referred to herein as a "positive" container), from the holding structure <NUM> to a positive container location, such as a positive container exit location or port <NUM> (see, e.g., <FIG>) where a user or technician can easily remove the positive container <NUM> from the detection system <NUM>. The transfer mechanism <NUM> (<FIG>) or <NUM> (<FIG>) can also be used to transfer a container <NUM> determined as negative for microbial growth after a designated time has passed (referred to herein as a "negative" container), from the holding structure <NUM> to a negative container location within the system (e.g., a negative container waste bin <NUM> (see, e.g., <FIG>)) where a user or technician can easily access the waste bin <NUM> for removal and disposal of the container <NUM>. As one of skill in the art would appreciate, other designs may be employed for the automated transfer mechanism and are described elsewhere herein.

The test system <NUM> will also include a detection system <NUM> (<FIG>) (which may be used interchangeably with the term "detector") for detecting growth in the specimen containers <NUM>. In general, any known detection system in the art for detecting microbial growth in a container can be used. For example, the holding structure <NUM> can cooperate with one or more linear scanning optical systems <NUM> that is configured to non-invasively monitor microorganism growth in each or a sub-set of specimen containers <NUM> held in a respective cell <NUM> of a rack 600r. In some particular embodiments, the optical system <NUM> can monitor or interrogate a sensor (e.g., a Liquid Emulsion Sensor (LES) sensor) <NUM> (<FIG>) in each of the specimen containers <NUM> to evaluate or detect for microorganism growth within the container <NUM>.

The test system <NUM> can be configured to automatically unload "positive" and/or "negative" specimen containers <NUM> when testing is complete. This can operate to ensure that once a "positive" or "negative" reading has been made for each specimen container <NUM>, the container <NUM> is removed from the cells <NUM> (see, e.g., <FIG>), making room for another container <NUM> to be loaded into the test system <NUM>.

The specimen container <NUM>, shown for example in <FIG>, is shown in the form of a standard culture bottle (e.g., a blood culture bottle). However, this example specimen container is offered by way of example only and is not limiting to the present inventive concept. As shown in <FIG>, the specimen container <NUM> comprises a top portion <NUM>, a body <NUM>, and a base <NUM>. The container <NUM> may include a bar code label <NUM> for automated reading of the container <NUM> within either the test system or off-line equipment. As shown in <FIG>, the top portion <NUM> of the container <NUM> typically comprises a narrow portion or neck <NUM> through which an opening <NUM> extends to provide communication with the interior chamber <NUM> of the container <NUM>. As also shown, the container <NUM> also includes a closure device <NUM> (e.g., a stopper), optionally having a pierceable septum and may also have an internal sensor <NUM> (e.g., an LES sensor) formed or placed in the bottom of the container <NUM> for purposes of colorimetric detection of the presence of microbial growth in the container <NUM>. However, the instant systems and methods can be adapted to a variety of specimen containers designed for culturing a test sample (e.g., a biological test sample).

The specimen containers <NUM> can comprise a test sample (e.g., a clinical or non-clinical biological sample) and can be loaded and unloaded into and out of the test system <NUM>. The container <NUM> may further comprise a growth or culture medium (not shown) for promoting and/or enhancing microbial or microorganism growth. The use of a growth or culture media (or medium) for the cultivation of microorganisms is well known. A suitable growth or culture medium provides the proper nutritional and environmental conditions for growth of microorganisms and should contain all the nutrients required by the microorganism which is to be cultivated in the specimen container <NUM>. After a sufficient time interval to allow natural amplification of microorganisms (this time interval varies from species to species), the container <NUM> can be tested within the test system <NUM> for the presence of microbial or microorganism growth. The testing may occur continuously or on a periodic basis so that the container <NUM> can be determined as positive for microorganism growth as soon as possible.

Once a container <NUM> in the system <NUM> is identified as positive, the system <NUM> can notify the operator through an indicator <NUM> (e.g., a visual prompt), and/or via a notification at the user interface display <NUM>, or by other means.

As shown in <FIG>, <FIG>, and discussed above, the transport mechanism <NUM> can comprise a conveyor belt <NUM> operable to transport (e.g., convey) the containers <NUM> to an entrance location or port <NUM> and subsequently through the entrance location or port <NUM> and into the test system <NUM>. However, other mechanisms for transporting the specimen containers <NUM> from an external loading station or area <NUM> to the entrance location or port <NUM> are envisioned, and may include, but are not limited to, feed screws, timing belts having grooves or molded plates, and the like. In other embodiments, the process of automated loading of a specimen container <NUM> into the test system <NUM> may further comprise transferring the container <NUM> into the test system <NUM> using a container locator device. See, e.g., FIGS. 27A-C, 28A-C, and <NUM> of <CIT>.

As shown in <FIG>, <FIG>, and discussed above, the loading station or area <NUM> and transport mechanism <NUM> can comprise a conveyor belt <NUM>. In accordance with this embodiment, the user or technician can place one or more specimen containers <NUM> at a specific location or area (i.e., the loading station or area <NUM>) of the conveyor belt <NUM> for automated loading of the containers <NUM> into the test system <NUM>. The conveyor belt <NUM> may run continuously, or may be activated by the physical presence of the container <NUM> at the loading station or area <NUM>. For example, a system controller can be used to operate the conveyor belt <NUM> (i.e., turn it on or off) based on a signal (e.g., a light sensor) indicating the presence, or absence, of one or more specimen containers at the loading station <NUM>. Similarly, one or more sensors can be used at the entrance location or port <NUM> to indicate if a container is improperly loaded and/or has fallen over and may cause jamming. The conveyor belt <NUM> operates to move or transport the containers <NUM> from the loading station or area <NUM> (e.g., the left portion of the conveyor belt <NUM>, as shown in <FIG>) to the entrance location or port <NUM>, thereby accumulating one or more containers <NUM> at the entrance location or port <NUM> to be loaded into the test system <NUM>. Typically, as shown in <FIG> and <FIG>, the loading station or area <NUM>, transport mechanism <NUM> or conveyor belt <NUM>, and entrance location or port <NUM> are located outside, or on the housing <NUM> of the test system <NUM>. In one embodiment, the automated loading mechanism <NUM> is located on a shelf <NUM> located on top of the lower section <NUM> and adjacent to the upper section <NUM> of the system <NUM>. Also, as shown, the transport mechanism or conveyor belt <NUM> typically operates in a horizontal plane, so as to maintain the specimen containers <NUM> in a vertical or up-right orientation (i.e., such that the top portion <NUM> of the container <NUM> is up) for loading into the test system <NUM> (see, e.g., <FIG> and <FIG>). As shown in <FIG>, the transport mechanism or conveyor belt <NUM> moves, for example, from left-to-right, or from the loading station or area <NUM> towards the entrance location or port <NUM>, to transport one or more free standing containers <NUM> (see, e.g., <FIG>, arrow <NUM>).

As shown, for example in <FIG> and <FIG>, the automated loading mechanism <NUM> can comprise one or more guide rails <NUM> located juxtaposed to one or both sides of the transport mechanism or conveyor belt <NUM>. The one or more guide rails <NUM> function to guide or direct the specimen containers <NUM> to the entrance location or port <NUM> during operation of the transport mechanism or conveyor belt <NUM>. The one or more guide rail(s) <NUM> can operate to funnel or guide the specimen containers <NUM> into a single file line at the back of the automated loading mechanism <NUM>, where they await their turn to be loaded, one container at a time, into the test system <NUM>.

The internal automated loading mechanism <NUM> (<FIG>) or <NUM> (<FIG>) can transfer a specimen container <NUM> within the internal chamber <NUM>. As already described, the entrance location or port <NUM> can receive containers <NUM> from, for example, a conveyor <NUM> shown in <FIG>. As the containers <NUM> accumulate in the entrance location or port <NUM>, the containers <NUM> can be moved within the test system <NUM> whereby the internal loading mechanism <NUM> (<FIG>) or <NUM> (<FIG>) can pick-up, or otherwise receive, an individual specimen container <NUM> and load that container into a selected cell <NUM> of the holding structure <NUM> within the test system <NUM>, as described in more detail herein.

The loading mechanism <NUM>, <NUM> may use a vision system (e.g., camera), pre-programmed dimensional coordinates correlated to cell locations with coordinate axis addresses, proximity sensors and/or precision motion control to load a respective specimen container <NUM> into a selected cell <NUM> of the holding structure <NUM>.

The containers <NUM> can be serially placed or held in a respective cell of one of a plurality of racks 600r of the holding structure <NUM>, and optionally agitated via a cooperating agitation assembly <NUM> (<FIG>) to enhance microorganism growth therein.

As shown for example in <FIG> and <FIG>, the holding structure <NUM> can comprise a plurality of stacked racks 600r with cells <NUM>. The stacked racks 600r can comprise four racks stacked vertically as shown in <FIG>. However, more or less numbers of such racks 600r can be used. Each rack 600r can comprise a plurality of stacked adjacent rows <NUM> of cells <NUM>, shown as eight rows with centerlines of cells in adjacent rows, one above another, offset from each other in a lateral direction. The cells <NUM> can be orientated to hold the specimen containers <NUM> horizontally. The cells <NUM> can each have a window 602w (<FIG>) that faces inward that allows visual access by the test system <NUM> (<FIG>). Accordingly, the automated loading mechanism <NUM> (<FIG>) or <NUM> (<FIG>) can rotate and/or re-orientate the container <NUM>, from a vertical orientation at intake into the interior chamber <NUM> of the test system <NUM> to a horizontal orientation before placing it into the selected cell <NUM> with the lid <NUM> (<FIG>) facing outward toward the front 104B (<FIG>) of the test system <NUM> and the bottom <NUM> (<FIG>) with the sensor <NUM> (<FIG>) facing the inner facing window 602w (<FIG>).

Referring to <FIG>, adjacent cells <NUM> in a row <NUM> may have vertically extending centerlines that are laterally spaced apart a distance D1, that may be in a range of <NUM>-<NUM> inches (<NUM>,<NUM>-<NUM>,<NUM>) in some embodiments. Cells <NUM> in adjacent neighboring rows <NUM> can have horizontally extending centerlines that are vertically spaced apart a distance D2, that may be in a range of <NUM>-<NUM> inches (<NUM>,<NUM>-<NUM>,<NUM>) or in a range of <NUM>-<NUM> inches (<NUM>,<NUM>-<NUM>,<NUM>). D1 <D2 in some embodiments.

In operation, the automated loading mechanism <NUM> (<FIG>), <NUM> (<FIG>) can operate to select a cell location, transfer or otherwise move or relocate a specimen container <NUM> within the interior chamber <NUM> of the test system <NUM>.

The loading mechanism <NUM> (<FIG>), <NUM> (<FIG>) can operate to place the container <NUM> in one of a plurality of container receiving structures or cells <NUM> that are located in the holding structure <NUM>. The loading mechanism can also operate to remove or unload "positive" and "negative" containers from the holding structures or racks <NUM>. This automated unloading mechanism can operate to ensure that once a "positive" or "negative" reading has been made for each specimen container <NUM>, the container <NUM> is removed from the container receiving structures or well <NUM>, making room for another container to be loaded into the test system <NUM>, thereby increasing system through-put.

The loading mechanism <NUM> (<FIG>), <NUM> (<FIG>) can comprise a robotic transfer arm. In general, any type of robotic transfer arm can be used. For example, the robotic transfer arm can be a multi-axis robotic arm (for example, a <NUM>-, <NUM>-, <NUM>-, <NUM>-, or <NUM>-axis robotic arm). The robotic transfer arm can operate to pick-up and transfer a specimen container <NUM> (e.g., a blood culture bottle) from an entrance location or port <NUM> to a selected one of a plurality of the cells <NUM> located in the holding structure <NUM>. Furthermore, the interior chamber <NUM> of the test system <NUM> may include one or more supports for the loading mechanism <NUM>, <NUM>. For example, one or more vertical supports and/or one or more horizontal supports may be provided. The transfer mechanism or robotic transfer arm will slide up and down and across the supports as necessary to access any of the cells <NUM> of the holding structure <NUM>.

Referring to <FIG>, the loading mechanism <NUM> can comprise a robotic transfer arm that cooperates with an upper horizontal support rail 652A, a lower horizontal support rail 652B, a single vertical support rail <NUM> and a robotic head <NUM> that can include a gripping mechanism (not shown) for picking-up, gripping or otherwise holding a specimen container <NUM>. As shown, the robotic head <NUM> is supported by, coupled to, and/or attached to the vertical support rail <NUM>, which in turn is supported by the horizontal support rails 652A and 652B. In operation, the vertical support rail <NUM> can be moved along the horizontal support rails 652A and 652B, thereby moving the vertical support rail <NUM> and the robotic head <NUM> along a horizontal axis (e.g., the x-axis). In general, any known means in the art can be used to move the vertical support rail <NUM> along the horizontal support rails 652A and 652B. For further details of example components of the loading mechanism <NUM>, see, e.g., <CIT> and <CIT>.

Referring to <FIG>, the loading mechanism <NUM> can include one or more horizontal support structures <NUM>, one or more vertical support structures <NUM>, and a robotic head <NUM> that can include one or more features or devices (e.g., a gripping mechanism) to pick-up, grip and/or hold a specimen container <NUM>. The robotic head <NUM> can be supported by, coupled to, and/or attached to one of the horizontal supports and/or vertical supports. For example, the robotic transfer arm <NUM> comprises a lower horizontal support structure 702B and a single vertical support structure <NUM>. Although not shown, as one of skill in the art would appreciate an upper horizontal support structure (not shown), or other similar structure can be used to further support or guide the vertical support structure <NUM>. The robotic head <NUM> can move up and down the vertical support rail <NUM> (as represented by arrow <NUM>) and move the vertical support rail <NUM> back-and-forth along the horizontal support structure(s) 702B (as represented by arrow <NUM>). For example, as shown in <FIG>, the loading mechanism <NUM> can include a vertical drive motor <NUM> and vertical drive belt that will operate to transfer or move the robotic head <NUM> up and down (arrow <NUM>) the vertical support rail <NUM> to transfer or move a container <NUM> along (i.e., up and down) a vertical axis (i.e., the y-axis). The vertical support structure <NUM> may further comprise a vertical guide rail <NUM> and a robotic head support block <NUM>, as shown in <FIG>. Accordingly, the vertical support structure <NUM>, vertical guide rail <NUM>, vertical drive motor <NUM> allow the robotic transfer arm <NUM> to move or transfer the robotic head support block <NUM>, and thus, the robotic head <NUM> and a specimen container <NUM> along the y-axis.

Likewise, also as shown in <FIG>, the robotic transfer arm <NUM> may further comprise a first horizontal drive motor <NUM>, first horizontal drive belt <NUM> and horizontal guide rail <NUM> that will operate to move the vertical support structure <NUM> back-and-forth (i.e., from left-to-right and/or from right-to-left) along the horizontal guide rail <NUM>, and thus, along a first horizontal axis (i.e., the x-axis) within the housing <NUM> of the detection system <NUM> (see arrow <NUM>)). Accordingly, the horizontal support structure(s) 702B, first horizontal drive motor <NUM>, first horizontal drive belt <NUM> and horizontal guide rail <NUM> allow the robotic transfer arm <NUM> to move or transfer a specimen container <NUM> along the x-axis. Applicant has found that a vertical support that is movable along a horizontal axis can allow for an increased capacity within the detection system, as the robotic transfer arm is movable over an increased area within the instrument.

Still referring to <FIG>, the automated loading mechanism <NUM> may further comprise a linear or horizontal slide <NUM> and pivot plate <NUM>. The linear or horizontal slide <NUM> can support the robotic head <NUM> and gripper mechanism <NUM>. The linear or horizontal slide <NUM> and robotic head <NUM> may be supported by, coupled to, and/or attached to, a robotic head support block <NUM> and vertical guide rail <NUM> (previously described). In accordance with this embodiment, the linear or horizontal slide <NUM> can be moved up and down along a vertical axis (i.e., the y-axis), via the a robotic head support block <NUM> and vertical guide rail <NUM>, to move or transfer the robotic head <NUM> and/or specimen container <NUM> up and down within the housing <NUM> of the detection system <NUM> (i.e., along the vertical axis (y-axis)). The linear or horizontal slide <NUM> may further comprises a pivot plate <NUM> comprising a pivot slot <NUM> that cooperates with a pivot slot cam follower operable to allow the robotic head <NUM> to slide or move along the linear or horizontal slide <NUM>, from front-to-back or from back-to-front, to transfer or move a container <NUM> along a second horizontal axis (i.e., the z-axis). For additional description of example components of the loading mechanism <NUM>, see, e.g., <CIT>.

The automated loading mechanism <NUM> (<FIG>), <NUM> (<FIG>) can be placed under the control of a system controller <NUM> (<FIG>, <FIG>) and programmed for specimen container <NUM> management (e.g., pick-up, transfer, selective loading placement and/or container removal) within the detection system <NUM>.

The holding structure <NUM> of the test system <NUM> can take a variety of physical configurations for handling a plurality of individual specimen containers <NUM> so that a large number of containers, e.g., typically in a range of <NUM>-<NUM> containers, depending on the specific holding structures used, can be processed simultaneously. The holding structure <NUM> can be used for storage, agitation and/or incubation of the specimen containers <NUM>.

Referring to <FIG>, <FIG> and <FIG>, the holding structure <NUM> comprises a plurality of vertically stacked container racks 600r each having a plurality of horizontally aligned specimen container receiving cells <NUM> in a row <NUM> and each cell can be sized and configured to hold an individual specimen container <NUM>. Two or more vertically stacked racks 600r can be used. For example, from about <NUM> to about <NUM>, from about <NUM> to about <NUM>, from about <NUM> to about <NUM>, from about <NUM> to about <NUM> and from about <NUM> to about <NUM> vertically stacked holding structures or racks can be used.

Referring to <FIG> and <FIG>, each rack 600r can have a unit housing <NUM> that may have a common housing size with others of the racks 600r and may have the same number of adjacent rows <NUM> or different numbers of adjacent rows <NUM> of cells <NUM>. As shown, there are four sub-units <NUM> within each unit housing <NUM> with two rows <NUM> of cells <NUM>. Referring to <FIG>, each rack 600r may have its own agitation assembly <NUM>.

As shown in <FIG>, each sub-unit <NUM> can have a defined number of cells that are serially numerically labeled with label <NUM>, shown as labeled above in the upper row and labeled below a respective cell as numbers <NUM>-<NUM>.

Referring to <FIG> the test system <NUM> includes a climate controlled interior chamber <NUM>, comprising an upper interior chamber <NUM> and a lower interior chamber <NUM>, and a plurality of vertically disposed holding structures or racks <NUM>, typically between <NUM>-<NUM> vertically stacked racks 600r, each rack 600r having a plurality of individual container receiving structures or wells <NUM> therein.

Each individual rack 600r can comprise a plurality of adjacent rows <NUM> of cells <NUM>. The number of adjacent rows <NUM> can be in a range of <NUM>-<NUM>, more typically <NUM>-<NUM>, shown as <NUM> in <FIG> and <FIG>. Each row <NUM> can have from about <NUM> to about <NUM> horizontally aligned cells, such as from about <NUM> to about <NUM>, from about <NUM> to about <NUM>, or from <NUM> to about <NUM> individual cells <NUM> therein. In some embodiments, the cells <NUM> in adjacent upper and lower neighboring rows <NUM> can be staggered, thus reducing the vertical height of each individual holding structure or rack <NUM> (see, e.g., <FIG>) and thereby allowing for an increased number of total holding structures or racks 600r in a given vertical distance within the incubation chamber <NUM>. As shown, for example in <FIG>, the detection system comprises <NUM> racks 600r each comprising two rows <NUM> of <NUM> individual cells <NUM> held in a unit housing <NUM>, thereby giving the system exemplified in <FIG> a total container capacity of <NUM>. More or less racks 600r can be used and more or less cells <NUM> can be provided.

Furthermore, each of the individual cells <NUM> has a specific coordinate position and/or address for container management, typically X is the horizontal location and Y is the vertical location of each container cell <NUM>.

Referring to <FIG>, a rack 600r can be agitated by an agitation assembly <NUM> to promote or enhance microorganism growth. The agitation assembly <NUM> can be any known means or mechanism for providing agitation (e.g., vibration and/or a rocking motion) to the holding structure <NUM>, sub-units <NUM> and/or racks 600r. In some particular embodiments, the racks 600r can be rocked in a back-and-forth motion for agitation of the fluid contained within the containers <NUM>. As shown in <FIG>, the agitation assembly <NUM> cooperates with one or more racks 600r comprising a plurality of holding wells <NUM> for holding a plurality of specimen containers <NUM>. The agitation assembly <NUM> can comprise an agitation motor <NUM>, an eccentric coupling <NUM>, a first rotation arm <NUM>, a second rotation arm or linkage arm <NUM> and a rack agitation bearing assembly <NUM>. In operation, the agitation motor <NUM> rotates the eccentric coupling <NUM> in an off-center motion thereby moving a first rotation arm <NUM> in an off-center circular or off-center rotational motion. The off-center rotational movement of the first rotation arm <NUM> moves a second rotation arm or linkage arm <NUM> in a linear motion (as represented by arrow <NUM>). The linear motion of the second rotation arm or linkage arm <NUM> rocks the rack agitation bearing assembly <NUM> in a back-and-forth rocking motion, thereby providing a back-and-forth rocking agitation motion (represented by arrow <NUM> of <FIG>) to the rack 600r.

Referring to <FIG>, each cell <NUM> can have a plurality of neighboring cells 602n. Using cell <NUM><NUM> as an example, the neighboring cells 602n can include twelve neighboring cells <NUM><NUM>-<NUM><NUM>. However, if the cell <NUM> is on an end of a row or end portion of a row, there may be lesser neighboring cells for that cell.

Also, what is considered a neighboring cell 602n for selecting an empty cell for loading can vary depending on spacing of cells and size of specimen containers, for example. However, it is contemplated that the number "n" of neighboring cells 602n used for selecting an appropriate cell for a newly intaken specimen container will include immediately adjacent neighboring cells in the same row and can include more peripheral cells. Thus, the number of neighboring cells 602n for an empty cell being evaluated for potential loading as will be discussed further below can be in a range of <NUM>-<NUM>, more typically in a range of <NUM>-<NUM>, including a range of <NUM>-<NUM>.

Thus, referring to <FIG>, in this example, cell <NUM> labeled as cell <NUM><NUM> is occupied as are neighboring cells <NUM> and <NUM> (<NUM><NUM>, <NUM><NUM>) in the row <NUM> above cell <NUM>, cells <NUM> and <NUM> (<NUM><NUM>, <NUM><NUM>) in the same row as cell <NUM>, and cells <NUM> and <NUM> (<NUM><NUM>, <NUM><NUM>) in the row below cell <NUM>. Cell <NUM> (<NUM><NUM>) and cell <NUM> (<NUM><NUM>) are spaced apart + <NUM> from cell <NUM> in the same row. The immediately adjacent or neighboring cells <NUM> and <NUM> (<NUM><NUM>, <NUM><NUM>) are unoccupied as are cells <NUM> and <NUM> above (<NUM><NUM>, <NUM><NUM>) and below (<NUM><NUM>, <NUM><NUM>) the row <NUM> that holds the occupied cell <NUM><NUM>. Other more peripheral cells are also unoccupied, i.e., cells <NUM>, <NUM> and <NUM> above and below the row with occupied cell <NUM> and cells <NUM> and <NUM> in the same row as occupied cell <NUM>. These more peripheral cells may not be considered as "neighboring" cells to cell <NUM> (if empty) when evaluating cell <NUM> as a respective empty cell to identify where to load a newly intaken specimen container as will be discussed further below. Typically, at least immediately adjacent cells in the same row as a respective empty cell <NUM> are considered neighboring cells. In some embodiments, the +<NUM> cells <NUM> in the same row <NUM> and on either side of an empty cell <NUM> are also included as neighboring cells. Also, at least first and second cells <NUM> immediately above and below the open empty cell (i.e., cells <NUM>, <NUM> in the example shown if cell <NUM> is the "empty" cell considered for loading) can also be considered neighboring cells. However, any adjacent row in a different rack 600r may be excluded as having any neighboring cells as the housing <NUM> or spacing of the rack units may provide sufficient thermal isolation.

As discussed above, the present inventive concept can electronically evaluate cells to identify which empty cell to load a newly intaken specimen container to reduce a likelihood of inducing a false positive test in the newly intaken specimen container and/or to specimen containers in already occupied cells.

The test system <NUM> can include or communicate with at least one processor <NUM>/<NUM> (<FIG>, <FIG>, <FIG>) that electronically identifies open cells for cell availability and electronically evaluates which of a plurality of different open cells to load with a newly intaken specimen container by considering empty or occupied content of its neighboring cells and a test status of any specimen container in a neighboring occupied cell. The test system <NUM> can ascertain whether a respective empty cell is more or less likely than other empty cells to put one or more tests of samples in specimen containers in occupied neighboring cells at risk of being identified with a false positive. The false positive can be induced by placing one or more newly intaken specimen containers (which are at a different temperature than in-test specimen containers) next to specimen containers in occupied neighboring cells during a critical test phase which can potentially cause undesired temperature fluctuation and influence sensor readings for the newly intaken specimen container or in in-test specimen containers.

The test system <NUM> can electronically evaluate some or all of the inventory of available empty cells with respect to status of neighboring cells and select an available empty cell <NUM> with a lowest or lower risk than other empty cells <NUM>, then direct the loading mechanism <NUM>, <NUM> to place the newly intaken specimen container <NUM> in the selected open cell with the least or lesser risk. The selective cell loading analysis can evaluate what test phase a specimen container <NUM> in the occupied cells of the neighboring cells 602n is in at a time of loading of the newly intaken container and can also consider whether there are other open cells in the neighboring cells 602n.

The test system <NUM> can calculate a neighboring factor and rank open and available cells <NUM> using the neighboring factor to assign lesser and higher risk values associated with a risk inducing a false positive if a particular empty cell is used for a newly intaken specimen container. The open cell <NUM> with the neighboring factor providing a least risk or a lower risk than other empty cells <NUM> can be selected.

Alternatively, instead of ranking all or some of the available and open cells, the selection can select one of the cells deemed to be of lesser risk than cells of greater risk based on the neighboring factor assessment. Thus, those cells deemed to be of higher risk such as above a median value of lesser risk cells are not selectable at the instant time of evaluation for intake of the newly incoming specimen bottle. Thus, while a ranking of relative risk is helpful it is not required for selection of lesser risk cells for loading the newly intaken specimen container.

As used herein, "cell availability" means the number of open unoccupied cells <NUM> in the holding structure <NUM> that are available for receiving a specimen container. Cells <NUM> in the holding structure <NUM> may already hold a specimen container <NUM> in them (i.e., "occupied"), may be malfunctioning, or may not be eligible for receiving a specimen container for another reason, in which case these cells are not considered available for loading with newly intaken specimen containers. The term "newly intaken" specimen container can be used interchanbeably with "incoming" specimen container and refers to a specimen container being provided to the test instrument for analysis. The newly intaken or incoming specimen container can be held outside the test instrument or in a loading chamber inside the test instrument or even held by the loading mechanism <NUM>, <NUM> ready for loading into a selected cell, once identified. As discussed above, a respective newly intaken specimen container <NUM> is typically at a lower temperature than the interior (incubation) chamber <NUM>. The "newly intaken" or "incoming" specimen container can be an untested specimen container or a re-test specimen container (i.e., the latter referring to a specimen container with a sample that may have had a prior incomplete or false test result).

The test instrument <NUM> and/or selective loading module <NUM> can identify the cell availability in a number of ways. For example, one or more cameras <NUM> (<FIG>) optionally positioned on an inside of the front door or doors <NUM>, <NUM> or otherwise held in the interior chamber <NUM> to be in visual communication with the cells <NUM> to obtain images used to identify which cells are occupied and which are empty and update the cell status using images obtained continuously or periodically or triggered by events such as a container being loaded and a container being unloaded. Alternatively or additionally, sensors <NUM> (<FIG>) such as proximity sensors, pressure sensors, optical sensors, hall-effect sensors and the like, can be coupled to each cell <NUM> and also coupled to a processor such as the system controller <NUM>/<NUM> (<FIG>, <FIG>). The sensors <NUM> can provide data that the system controller <NUM>/<NUM> can monitor to identify a respective cell status of the cells <NUM> as "empty" or "occupied".

<FIG> illustrates exemplary actions or operations that can be used to carry out embodiments of the invention. An electronic inventory of cell availability of unoccupied cells in a test instrument with an incubator is provided and/or obtained (block <NUM>). Empty cells are electronically identified and evaluated to determine whether a respective empty cell, if loaded with a newly intaken specimen container, is more or less likely to put one or more specimen containers at risk of having a false positive (block <NUM>). An automated loader can be electronically directed to load one of the empty cells identified to be less likely with the newly intaken specimen container thereby avoiding loading empty cells identified as more likely (block <NUM>).

At-risk numerical values for empty cells can be calculated based on a defined neighboring factor that comprises a cell criticality value associated with test status of a respective specimen container (if any) in neighboring cells of respective empty cells (block <NUM>).

The at-risk numerical values for each empty cell can be calculated as weighted sums of cell critical parameter values of respective defined sets of neighboring cells (block <NUM>).

The cell criticality value can consider a time from load of each of the specimen containers in occupied ones of the neighboring occupied cells to ascertain if a respective test is in a critical test phase (which can optionally have a lower decision reflectance threshold range relative to an earlier test phase)(block <NUM>).

A number of criteria can be taken into consideration to determine the risk level that each vacant cell has on the current bottles under test. Each of these criteria can be given a weight to differentiate which criteria have the greatest impact on false positives. The weights assigned to each criteria can be modified. The weights on the criteria can be referred to as adjustable parameters that may be tuned to tailor a loading selection process for the environment, sensor and detector type and conditions that a particular test instrument is used in.

Embodiments of the invention use methodology to predict where the worst cell location to load a bottle is, and then try to avoid that place. To determine if one empty cell is worse than another for loading with a specimen container <NUM>, a plurality of variables, such as <NUM>-<NUM> variables can be evaluated and weights assigned to those variables.

Neighboring cells can be characterized into different categories and each category can have a different weight. For example, the neighboring cells can include three different categories: immediately adjacent (on either side of the empty or vacant cell), opposite row (two closest cells in another adjacent row, above or below the row with the vacant cell) and cells spaced further away from directly adjacent cells (i.e., on either side, but +<NUM> cell away and optionally also +<NUM> cells). All neighboring cells 602n can be in the same rack 600r or in a single sub-unit <NUM> (<FIG>, <FIG>). The immediately adjacent cells can have a weight that is greater than the weights of the other two categories of neighboring cells.

For example, a first category can have an Adjacent Weight: Weight given to the cells immediately adjacent to a given cell in the same row of the same rack. A second category can be an Opposite Weight: Weight given to the cells diagonally adjacent to a given cell in the opposite row of the same rack or sub-unit. A third category can be a Further Weight: Weight given to the cells two cells away from a given cell in the same row of the same rack. The Adjacent Weight > The Opposite Weight> The Further Weight. The Adjacent Weight can be <NUM>. The Opposite Weight can be <NUM> and the Further Weight can be <NUM>. However, other weights can be used.

The BACT/ALERT® VIRTUO® blood culture test instrument uses a colorimetric optical system for detecting the positivity of a blood culture test and the colorimetric optical system is composed of multi-color LEDs and a photodiode, which are susceptible to variation based on environmental temperature fluctuations. The present invention provides a "smart" loading process to avoid loading at-risk vacant cells to reduce the temperature variation on the colorimetric optical system. However, the "smart" loading process can also be implemented on any system that utilizes a sensing method that is sensitive to temperature fluctuation. Other blood culture instruments use fluorescent based sensing systems, instead of colorimetric, which can also be impacted by changes in environmental temperature. These systems would also show changes in sensor readings based on the introduction of a sample at different temperatures, and could be mitigated by predicting the effects of that new sample in vacant locations. For example, some test systems employ infrared (IR) and fluorescent indicators to determine when specimen containers are positive. Temperature fluctuations can cause fluorescent material to change excitation states, which in turn gives off a fluorescent signal. Therefore, a system using IR & fluorescent signals may benefit from a "smart" loading selection process according to embodiments of the present invention.

The smart loading system can electronically review open and available cells according to defined criteria including a cell criticality factor based on status of an open cell's neighbor cells and rank and/or sort those open cells as cells to avoid and/or preferred cells for loading. The sorting can be based on a threshold value of "bad" or "good" locations or a relative value of "good" or "bad" associated with those cells that are open and available.

<FIG> illustrates exemplary actions or operations that can be used to carry out embodiments of the invention. A test instrument with an incubation chamber and a plurality of cells for holding specimen containers is provided (block <NUM>). Empty cells and corresponding neighboring cell locations are identified (block <NUM>). A value of a cell criticality parameter for each of the neighboring cell locations is calculated based on whether a respective cell is unoccupied and/or a test state of a respective specimen container in an occupied cell (block <NUM>). Where to load an incoming specimen container is electronically selected based on a calculated neighboring factor parameter determined by a sum of cell criticality parameters of the neighboring cell locations to thereby avoid at-risk cell locations associated with potential false positives due to temperature induced reactions of sensors of the specimen containers (block <NUM>). The values of the cell criticality parameter can be automatically recalculated along with a corresponding neighboring factory parameter upon defined triggering events and/or periodically and upon each new load or reload of a specimen container into the detection instrument to select where to load a subsequent incoming specimen container (block <NUM>).

The defined triggering events can include a new load, an unload, a remove and replace indexer cover, an open door, a reboot start and a reboot end, particularly if a triggering event happens during a critical test phase.

The term "critical test phase" refers to that part of a sample test cycle where microbial growth is more sensitive to a temperature fluctuation and/or where decision threshold limits for "positive" and "negative" test characterizations are reduced relative to other test phases. The critical test phase is typically at a time that is greater than <NUM> hours from initial load of a new and untested specimen container into the test instrument.

The term "neighboring" cells with respect to an empty or vacant cell analyzed for cell criticality can refer to: (a) cells that are only on immediately adjacent sides of an empty or vacant cell; (b) cells that are on immediately adjacent sides and immediately above and/or below the vacant or empty cell; (c) cells that are immediately adjacent and cells that have a + <NUM> cell spacing; or (d) cells that are immediately adjacent and cells with a + <NUM> spacing side to side and one or more closest cells in one or more adjacent row that is above or below the open cell being analyzed for selection (block <NUM>).

A sensor such as an LES sensor or an IR sensor (for fluorescence) can be monitored to identify the respective test state for the specimen containers (block <NUM>).

The cell criticality parameter can be periodically recalculated (i.e., every <NUM>-<NUM> minutes during active loading) and/or upon each successive new load based on changing dynamics of the test status (block <NUM>).

A time from load for each neighboring specimen container of an empty cell can be electronically determined or obtained and used to identify whether the sample is in a critical test phase (block <NUM>) and this time can optionally be used to either or both increase the cell criticality value if the sample is identified in the critical test phase or exclude that empty cell from being loaded with the newly intaken specimen container. Thus, the cell criticality parameter can optionally consider the time from load of the specimen container in the neighboring occupied cells to ascertain if the test is in a critical test phase, as this test phase can have a lower reflectance decision threshold range relative to an earlier test phase(s).

The cell criticality parameter can be negative, positive or <NUM> (block <NUM>).

The neighboring factor parameter can be a sum of individual critical weight parameters and each of the individual weight parameters can be weighted depending on a distance of an unoccupied cell for potential selection to load the newly intaken specimen container to a corresponding neighboring occupied cell (block <NUM>).

The cell criticality parameter can be <NUM> for an empty cell, and -<NUM> to <NUM> for an occupied (i.e., loaded) cell in the neighboring cells (block <NUM>).

A data gap in test data of samples in specimen containers associated with an open door condition of the instrument can be electronically monitored and a value for the cell criticality parameter of loaded cells can be increased relative to a default cell criticality value absent the open door condition (block <NUM>).

The containers can optionally comprise blood samples.

<FIG> illustrates that the test system <NUM> can include a holding structure comprising a cell array <NUM>, a loader <NUM>, <NUM>, a detection system <NUM> and an onboard selective cell loading module <NUM> that can be in communication with or totally or partially onboard the system controller and/or processor <NUM>/<NUM>. The test system <NUM> can be in communication with an LIS <NUM>.

<FIG> illustrates that the test system <NUM> can communicate with a remotely located selective cell loading module <NUM>, at least one processor <NUM> which may reside in one or more servers <NUM> and/or an LIS <NUM>.

The test system <NUM> can be included as one component of an automated laboratory system. The test system <NUM> can be coupled to, "daisy chained" or otherwise linked to one or more other systems or modules, for example, identification testing systems such as the VITEK or VIDAS systems of the assignee bioMérieux, Inc. , a gram stainer, a mass spectrometry unit, a molecular diagnostic test system, a plate streaker, an automated characterization and/or identification system (as disclosed in <CIT>) or other analytical systems.

The present invention is described in part with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention.

The flowcharts and block diagrams of certain of the figures herein illustrate exemplary architecture, functionality, and operation of possible implementations of embodiments of the present invention. It should be noted that in some alternative implementations, the steps noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order or two or more blocks may be combined, depending upon the functionality involved.

As discussed above, embodiments of the present invention may take the form of an entirely software embodiment or an embodiment combining software and hardware aspects, all generally referred to herein as a "circuit" or "module. " Furthermore, the present invention may take the form of a computer program product on a computer-usable storage medium having computer-usable program code embodied in the medium. Any suitable computer readable medium may be utilized including hard disks, CD-ROMs, optical storage devices, a transmission media such as those supporting the Internet or an intranet, or magnetic storage devices. Some circuits, modules or routines may be written in assembly language or even micro-code to enhance performance and/or memory usage. It will be further appreciated that the functionality of any or all of the program modules may also be implemented using discrete hardware components, one or more application specific integrated circuits (ASICs), or a programmed digital signal processor or microcontroller. Embodiments of the present invention are not limited to a particular programming language.

Computer program code for carrying out operations of data processing systems, method steps or actions, modules or circuits (or portions thereof) discussed herein may be written in a high-level programming language, such as Python, Java, AJAX (Asynchronous JavaScript), C, and/or C++, for development convenience. In addition, computer program code for carrying out operations of exemplary embodiments may also be written in other programming languages, such as, but not limited to, interpreted languages. Some modules or routines may be written in assembly language or even micro-code to enhance performance and/or memory usage. However, embodiments are not limited to a particular programming language. As noted above, the functionality of any or all of the program modules may also be implemented using discrete hardware components, one or more application specific integrated circuits (ASICs), or a programmed digital signal processor or microcontroller. The program code may execute entirely on one computer (e.g., a test instrument computer and/or processor), partly on one computer, as a stand-alone software package, partly on the test instrument/system computer and partly on another computer, local and/or remote or entirely on the other local or remote computer. In the latter scenario, the other local or remote computer may be connected to the test instrument/system <NUM> computer and/or processor through a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing some or all of the functions/acts specified in the flowchart and/or block diagram block or blocks.

As illustrated in <FIG>, embodiments of the invention may be configured as a data processing system <NUM>, which can be used to carry out or direct operations of the test instrument/system <NUM>, and can include a processor circuit <NUM>, a memory <NUM> and input/output circuits <NUM>. The data processing system may be incorporated in, for example, one or more of a computer, server, router or the like. The system <NUM> can reside on one machine, such as in the controller <NUM> (<FIG>) or be distributed over a plurality of machines. The processor <NUM> can communicate with the memory <NUM> via an address/data bus <NUM> and communicate with the input/output circuits <NUM> via an address/data bus <NUM>. The input/output circuits <NUM> can be used to transfer information between the memory (memory and/or storage media) <NUM> and another computer system or a network using, for example, an Internet protocol (IP) connection. These components may be conventional components such as those used in many conventional data processing systems, which may be configured to operate as described herein.

In particular, the processor <NUM> can be commercially available or custom microprocessor, microcontroller, digital signal processor or the like. The memory <NUM> may include any memory devices and/or storage media containing the software and data used to implement the functionality circuits or modules used in accordance with embodiments of the present invention. The memory <NUM> can include, but is not limited to, the following types of devices: ROM, PROM, EPROM, EEPROM, flash memory, SRAM, DRAM and magnetic disk. In some embodiments of the present invention, the memory <NUM> may be a content addressable memory (CAM).

As further illustrated in <FIG>, the memory (and/or storage media) <NUM> may include several categories of software and data used in the data processing system: an operating system <NUM>; application programs <NUM>; input/output device drivers <NUM>; and data <NUM>.

As will be appreciated by those of skill in the art, the operating system <NUM> may be any operating system suitable for use with a data processing system, such as IBM®, AIX® or zOS® operating systems or Microsoft® Windows2000 or WindowsXP operating systems, Windows Visa, Windows7, Windows CE or other Windows versions from Microsoft Corporation, Redmond, WA, Palm OS, Symbian OS, Cisco IOS, VxWorks, Unix or Linux™, Mac OS from Apple Computer, LabView, or proprietary operating systems. IBM, AIX and zOS are trademarks of International Business Machines Corporation in the United States, other countries, or both while Linux is a trademark of Linus Torvalds in the United States, other countries, or both. Microsoft and Windows are trademarks of Microsoft Corporation in the United States, other countries, or both. The input/output device drivers <NUM> typically include software routines accessed through the operating system <NUM> by the application programs <NUM> to communicate with devices such as the input/output circuits <NUM> and certain memory <NUM> components. The application programs <NUM> are illustrative of the programs that implement the various features of the circuits and modules according to some embodiments of the present invention. Finally, the data <NUM> represents the static and dynamic data used by the application programs <NUM> the operating system <NUM> the input/output device drivers <NUM> and other software programs that may reside in the memory <NUM>.

The data <NUM> may include test data of occupied cells and/or a time from load to test phase correlation data sets <NUM>.

The module <NUM> can be provided as sub modules that are distributed over different servers or clients or may be provided as sub modules or subroutines on a respective server <NUM> (<FIG>) or client associated with the test system <NUM>. The at least one server <NUM> can be provided using cloud computing which includes the provision of computational resources on demand via a computer network. The resources can be embodied as various infrastructure services (e.g., compute, storage, etc.) as well as applications, databases, file services, email, etc. In the traditional model of computing, both data and software are typically fully contained on the user's computer; in cloud computing, the user's computer may contain little software or data (perhaps an operating system and/or web browser), and may serve as little more than a display terminal for processes occurring on a network of external computers. A cloud computing service (or an aggregation of multiple cloud resources) may be generally referred to as the "Cloud". Cloud storage may include a model of networked computer data storage where data is stored on multiple virtual servers, rather than being hosted on one or more dedicated servers.

As further illustrated in <FIG>, according to some embodiments of the present invention, application programs <NUM> can include a Selective Cell Location Loading Module <NUM> and a User Interface Random or Selected Loading Module <NUM>. The latter allows a user to select which type of loading of newly intaken specimen containers to activate for use. The application program(s) <NUM> may be located in a local server (or processor) and/or database or a remote server (or processor) and/or database, or combinations of local and remote databases and/or servers.

While the present invention is illustrated with reference to the application programs <NUM>, and Modules <NUM>, <NUM> in <FIG>, as will be appreciated by those of skill in the art, other configurations fall within the scope of the present invention. For example, rather than being application programs <NUM> these circuits and modules may also be incorporated into the operating system <NUM> or other such logical division of the data processing system. Furthermore, while the application programs <NUM>, <NUM> are illustrated in a single data processing system, as will be appreciated by those of skill in the art, such functionality may be distributed across one or more data processing systems in, for example, the type of client/server arrangement described above. Thus, the present invention should not be construed as limited to the configurations illustrated in <FIG> but may be provided by other arrangements and/or divisions of functions between data processing systems. For example, although <FIG> is illustrated as having various circuits and modules, one or more of these circuits or modules may be combined or separated without departing from the scope of the present invention.

The Selective Cell Loading Module <NUM> can define "Bottle Neighbors" as comprising three categories of neighboring cells: adjacent (on either side), opposite row (two closest cells in the other row) and further (on either side, but <NUM> cell away, further from adjacent). All bottle neighbors (also interchangeably discussed as neighboring cells 602n) can be in the same rack.

The Selective Cell Loading Module <NUM> can provide a Cell Criticality list or chart that provides an array of cell criticality values corresponding to the number of cells. For example, an array of <NUM> values where there are <NUM> cells, (one for each cell) that determines a cell criticality value for neighboring cells that are empty or occupied and if the latter, how critical the bottle test is for that cell. A high value means that the loaded bottle is at a critical test phase or state. Unloaded or "empty" cells can have a value of <NUM> and loaded cells may be positive, negative or zero. This list can be recalculated for loaded cells every <NUM> minutes based on the changing dynamics of the cell evaluation. The values also change for a cell when a bottle is loaded or unloaded from that cell.

The Selective Cell Loading Module <NUM> can then generate an Available Cell List. This is a list of empty available cells that is typically recalculated and resorted at every bottle load. However, the list may include only a sub-set of available cells and is not required to include all available cells. Each list element contains two members, the cell number and the Neighbor Factor. The Neighbor Factor for an empty cell is determined based on the cell criticality values of its neighboring cells. In some embodiments, the Neighboring Factor is calculated as the sum of the cell criticality values of its neighboring cells, optionally with a weight depending on the neighbor's distance. The available cells can be sorted according to the Neighbor Factor, typically with the lowest value at the top of the list. The value at the top of the list is used to select the next cell to be loaded. Since there can be a latency between loading a cell and selecting the next cell (there may be a bottle in the robot assigned a cell that appears to be available), the last cell selected is stored and removed from the available cell list. Also, it is noted that the reverse order can be used, i.e., the lowest value placed at the bottom of the list and the cell at the bottom selected then removed from the available cell list.

Different events in the instrument can trigger certain calculations. For example, the Available Cell List can be updated based on:.

Furthermore, for clarity, in general, the test system <NUM> can be configured to employ any known means in the art for monitoring and/or interrogating a specimen container <NUM> for the detection of microbial growth. As previously mentioned, the specimen containers <NUM> can be monitored continuously, or periodically, during incubation of the containers <NUM> in the test system <NUM>, for the positive detection of microbial growth. Various design configurations for the detector <NUM> can be employed within the test system. For example, the detector <NUM> (<FIG>, <FIG>) can comprise a single detector for an entire rack 600r or even an entire holding structure <NUM> or can comprise multiple detectors per rack and/or per holding structure <NUM>.

In some embodiments, a detector <NUM> (<FIG>, <FIG>) reads the sensor <NUM> incorporated into the bottom or base <NUM> of the container <NUM> (<FIG>). The detection unit <NUM> can take colorimetric measurements as described in the <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>.

A positive container is indicated depending upon these colorimetric measurements, as explained in these patents. Alternatively, detection could also be accomplished using intrinsic fluorescence of the microorganism, and/or detection of changes in the optical scattering of the media. See, <CIT>.

In yet another embodiment, detection can be accomplished by detecting or sensing the generation of volatile organic compounds in the media or headspace of the container <NUM>.

As previously described, the test system <NUM> may include a climate-controlled interior chamber (or incubation chamber) <NUM>, for maintaining an environment to promote and/or enhance growth of any microbial agents (e.g., microorganisms) that may be present in the specimen container <NUM>. In accordance with these embodiments, the test system <NUM> may include a heating element or hot air blower to maintain a constant temperature within the interior chamber <NUM>. For example, in one embodiment, the heating element or hot air blower will provide and/or maintain the interior chamber <NUM> at an elevated temperature (i.e., a temperature elevated above room temperature). In other embodiments, the test system <NUM> may include a cooling element or cold air blower (not shown) to maintain the interior chamber at a temperature below room temperature. The interior chamber or incubation chamber can be at a temperature of from about <NUM>° to about <NUM>° C. The interior chamber <NUM> can be an incubation chamber and can be maintained at a temperature from about <NUM>° C to about <NUM>° C, and preferably at about <NUM>° C. In other embodiments, the interior chamber <NUM> may be maintained at a temperature below room temperature, for example from about <NUM>° C to about <NUM>° C, and preferably at about <NUM>° C. A particular advantage provided is the ability to provide a more constant temperature environment for promoting and/or enhancing microbial growth within a specimen container <NUM>. The test system <NUM> can have a closed system, in which automated loading, transfer and unloading of specimen containers <NUM> occurs without the need to open any access panels that would otherwise disrupt the incubation temperature (from about <NUM>° to <NUM>° C, preferably from about <NUM>° C) of the interior chamber <NUM>. If a door of the housing <NUM> is opened, a data flag may be generated for a test result of impacted specimen containers <NUM> to adjust a critical cell value which may help avoid false positives associated with this trigger event as the change in temperature in regions of the interior chamber <NUM> due to the open door can affect test results, particularly if in a critical phase of the test of the sample where decision thresholds may be relatively small, for example. One or more thermistors or other temperature sensors <NUM> (<FIG>) for a rack 600r, a row <NUM> or a set of cells <NUM> may be used to provide temperature feedback to the system controller <NUM> and/or location selection module <NUM> (<FIG>, <FIG>, <FIG>).

A cold (ambient or chilled) newly intaken specimen container <NUM> can cause a reflectance jump of an adjacent container <NUM> which can result in a false positive, particularly if the newly intaken specimen container <NUM> is loaded during a critical test phase of the adjacent container <NUM>. Also, a reloaded (i.e., retest) bottle that is identified positive or without a test result during a first test and unloaded from the instrument <NUM> can result in a false positive if reloaded late in a test cycle for that reloaded bottle. The selective loading module <NUM> can weight the cell criticality parameter for an occupied cell holding a reloaded/retest specimen with an increased weight relative to even specimen containers in the critical test phase.

The test system <NUM> can include a system controller <NUM> (e.g., a computer control system) (<FIG>, <FIG>) and firmware for controlling the various operations and mechanisms of the system. The system controller and firmware for controlling the operation of the various mechanisms of the system can be any known conventional controller and firmware known to those of skill in the art. In some embodiments, the controller <NUM> can perform the operations for controlling the various mechanisms of the system, including: automated selective loading, automated transfer, automated detection and/or automated unloading of specimen containers from/within the system. The controller <NUM> and firmware can also provide for identification and tracking of specimen containers <NUM> within the system.

The detection system <NUM> may also include a user interface <NUM> and associated computer control system for operating the loading mechanism, transfer mechanism, racks, agitation equipment, incubation apparatus, and receiving measurements from the detection units. These details are not particularly important and can vary widely. When a container is detected as being positive, the user can be alerted via the user interface <NUM> and/or by the positive indicator <NUM> (see, e.g., <FIG>) becoming active (i.e., an indicator light turning on). As described herein, upon a positive determination, the positive container can be automatically moved to a positive container location <NUM>, shown for example in <FIG> for retrieval by a user.

The user interface <NUM> may also provide an operator or laboratory technician with status information regarding containers loaded into the detection system. The user interface may include one or more of the following features: (<NUM>) Touch screen display; (<NUM>) Keyboard on touch screen; (<NUM>) System status; (<NUM>) Positives alert; (<NUM>) Communications to other systems (DMS, LIS, BCES & other detection or identification Instruments); (<NUM>) Container or bottle status; (<NUM>) Retrieve containers or bottles; (<NUM>) Visual and audible Positive Indicator; (<NUM>) USB access (back ups and external system access); and (<NUM>) Remote Notification of Positives, System Status and Error Messages.

Non-Limiting Examples will be discussed below.

The BACT/ALERT® VIRTUO® instrument processes BacT/ALERT bottles containing clinical samples to detect microorganisms such as bacteria in the sample. The instrument automatically scans bottles and loads them into racks. Once the bottles are loaded in the racks, the instrument incubates and agitates the bottles, periodically measures the reflectance of the bottom of each bottle, and analyzes the reflectance measurements to determine a positive or negative result for each bottle.

It has been observed that bulk loading of ambient/room temperature ('cold') bottles can have a significant effect on previously loaded and incubated ('warm') bottles, which can cause 'warm' bottles to falsely register as positive. This happens when the 'cold' bottles have enough of an effect on the 'warm' incubated bottles (either by proximity or a bulk load) to suddenly decrease their temperature, which causes a jump in reflectance that sometimes exceeds the bottle result decision limits. This can prompt the instrument to label that bottle as a positive sample, which is considered a false positive.

When the temperature in the instrument is increased, the LED reflectance decreases, and vice versa. This happens because a temperature increase causes the anode and cathode to separate in distance, which in turn causes the current transferred between them to decrease. This decreased current then outputs a weaker light, which equates to a lower reflectance value.

By analyzing the bottles' reflectances in decision limits ('DerivHighLimit' and 'AreaHighLimit' values), it was determined that FA Plus and SA bottle types with broth only have the smallest decision limits but test samples with blood content may be more susceptible to temperature induced reflectance changes.

Generally stated, the effects of temperature changes on bottles with and without blood were evaluated as were LED reflectance values over time based on various loading of cells. In summary, nine refrigerated bottles (three each of SN, SA, and FA Plus with <NUM> blood added, <NUM> water added, or just broth) were loaded into a Virtuo instrument at <NUM>. The reflectance values of each of the nine bottles were then recorded, and compared against the decision limits calculated by the instrument. This was done to determine which qualities are associated with smaller decision limits, or which bottle's reflectance readings can vary the least but still go past the decision limits, labeling that bottle positive.

For example, a bottle with no added blood was loaded next to an incubated bottle inoculated with <NUM> of blood. The reflectance increase is about <NUM> counts as shown in <FIG>. A bottle inoculated with <NUM> of blood was loaded next to an incubated bottle inoculated with <NUM> of blood. The reflectance increase is about <NUM> counts as shown in <FIG>.

<FIG> show that door open/close events have the most significant effect on the internal temperature (middle thermistor temperature, <FIG>) and reflectance (<FIG>). These open door events are identifiable on the temperature graph of <FIG> as sharp declines, and on the reflectance graph (<FIG>) as sharp increases lasting for only a matter of seconds, which then fall back down to their original position. Thus, opening of the instrument door during incubation causes a steep drop in temperature, which causes an increase in reflectance and a unique curve shape associated with the door open events.

Graphs were analyzed alongside intermediate calculations that are used to determine a bottle's positive/negative result. By analyzing the bottles' reflectances in accordance with these decision limits ('DerivHighLimit' of <FIG>) and 'AreaHighLimit' values, it was determined that FA Plus and SA bottle types with broth only have the smallest decision limits.

In addition, bottles with added water do not experience a significant reflectance increase over time, but all bottles with added blood do, along with SN and SA bottles containing broth only. The bottles with blood undergo a spike much larger than the bottles with broth only - reflectance increases ranging from about <NUM>-<NUM> counts versus increases of only about <NUM> counts in the broth only bottles.

<FIG> shows data regarding the partitioning of the DerivHighLimit decision limits, generated as intermediate calculations from a continuous monitoring test. The plots were split into three different phases, in order to determine a time frame for when a bottle becomes most susceptible ("critical" test phase) to temperature changes during its incubation. This happens during Phase <NUM>, where the limits level out after a certain amount of time. On average, Phase <NUM> ends at <NUM> hours, and Phase <NUM> ends at <NUM> hours. So, bottles loaded after <NUM> hours are most likely to be affected by peripheral bottle loads, as that is when the limits are at their smallest values.

The testing shows that peripheral loads surrounding an incubated bottle do have a noteworthy effect on the bottle's reflectance measurements. If this bottle is in the critical part of testing, where the decision limits are the smallest, a load peripheral to it (i.e., adjacent neighbors) and potentially more peripheral neighbors such as at a +<NUM> offset could cause it to be falsely determined as positive.

The following definitions can be assigned to example parameters that can be used for selective loading with the example pseudo code provided below, by way of example only.

Reload: A bottle that was loaded, but had previously been loaded and unloaded.

Derivative: The slope between the last two sample readings.

Derivative Positive Count: The number of consecutive readings where the Derivative value is above the Upper Derivative limit.

Area Positive Count: The number of consecutive readings where the Relative Area Under the Curve value is above the
Relative Area Under the Curve limit.

Upper Derivative Limit: A data-dependent decision limit based on the derivative.

Data Gap Flag: Set to <NUM> if there has been a readings time gap in the data of greater than <NUM> minutes. The flag is reset after a varying period of time that is data dependent.

Relative Area Under the Curve: A calculation of the change in area of the data reflectance vs. time curve.

Adjacent Weight: Weight given to the cells immediately adjacent to a given cell in the same row of the same rack. Typically <NUM>.

Opposite Weight: Weight given to the cells diagonally adjacent to a given cell in the opposite row of the same rack. Typically <NUM>.

Further Weight: Weight given to the cells two cells away from a given cell in the same row of the same rack. Typically <NUM>.

End Factor: Criticality value given to the imaginary cells at the end of the rack. (e.g. There is no left neighbor to cell <NUM>, but it is given the value of End Criticality as if there were a cell there. ) Typically -<NUM>.

Initial Factor: Criticality value given to newly loaded bottles and very recently reloaded bottles. Typically -<NUM>.

Positive Derivative Factor: Criticality given to a bottle called positive due to Derivative. Typically <NUM>.

Positive Non-Derivative Factor: Criticality given to a bottle called positive due to reason other than Derivative. Typically <NUM>.

Count Factor: Criticality used when calculating bottles during the critical growth phase. Typically <NUM>.

Count Factor Limit: Limit of the maximum Count Factor value. Typically <NUM>.

Reload Factor: Criticality value given to a reloaded bottle. Typically <NUM>.

Residual Factor: Criticality value given to bottles with a high derivative value, but no other weight. Typically <NUM>.

Loaded Factor: Criticality value given to a loaded bottle that has no other criticality. Typically <NUM>.

Gap Factor: Criticality value used when a bottle has the Data Gap Flag set. Typically <NUM>. <IMG>
<IMG>
<IMG>.

As a bottle is ready to load via the robot, a cell to load is determined from a sorted list of empty cells according to the Criticality Value of its neighboring cells. The cell with the lowest sum is chosen as the next cell to load. The criticality of the imaginary cells at the ends of the racks are given value -<NUM>. This initially favors the ends of the racks for loading. <IMG>
<IMG>.

<FIG> & <FIG> illustrate exemplary flow charts of actions for the smart loading of specimen containers.

Referring to <FIG>, a bottle is scanned and ready to load into a cell (block <NUM>). The predictive loading process is performed (block <NUM>). The bottle is loaded into an empty cell selected by the predictive loading process (block <NUM>).

<FIG> illustrates that a predictive loading process can be initiated or started (block <NUM>). A cell criticality subprocess can be performed (block <NUM>). An available cell sensitivity subprocess can be performed (block <NUM>). The predictive loading process can be completed for a respective specimen container (block <NUM>).

<FIG> is an example of the cell criticality subprocess <NUM> in <FIG>. A cell criticality subprocess is started (block <NUM>). For each cell, the following is carried decision tree process can be performed (block <NUM>). Have all cells been processed? (block <NUM>). Is cell empty? (block <NUM>). If yes, set cell criticality to <NUM> (block <NUM>). If no, was cell loaded since last reading? (block <NUM>). If yes, set cell criticality to initial factor (block <NUM>). If no, read detection algorithm calculations based on periodic bottle readings (block <NUM>). Perform bottle impact analysis subprocess (block <NUM>). Store cell critically for this cell and advance to the next cell (block <NUM>). The cell criticality subprocess can be ended (block <NUM>).

<FIG> is an example bottle impact subprocess (bock <NUM>) shown in <FIG>. A bottle impact analysis subprocess can be started (block 1120i). Set cell criticality to <NUM> (block <NUM>). Is bottle positive not due to Derivative? (block <NUM>) If yes, set cell criticality to positive non-derivative factor (block <NUM>). If no, was bottle loaded < <NUM> hours ago or reloaded < <NUM> minutes ago? (block <NUM>). If yes, decrease cell criticality by initial factor (block <NUM>). If no, increase cell criticality by count factor multiplied by the sum of derivative positive count and area positive count. Limit the increase to count factor limit (block <NUM>). Was bottle reloaded < <NUM> hours ago? (block <NUM>) If yes, increase cell criticality by reload factor (block <NUM>). If no, is cell criticality < positive derivative factor and bottle positive due to derivative? (block <NUM>). If yes, set cell criticality to positive derivative factor (block <NUM>). If no, is cell criticality zero? (block <NUM>). If yes, increase cell criticality by residual factor multiplied by absolute value of the derivative divided by the upper derivative limit. Limit the increase to residual factor (block <NUM>). If no, is cell criticality zero? (block <NUM>). If yes, set cell criticality to loaded factor (block <NUM>). If no, is data gap flag set? (block <NUM>). If yes, set cell criticality to gap factor (block <NUM>). If no, end bottle impact analysis subprocess (block 1120e).

<FIG> is an example available cell sensitivity subprocess <NUM> shown in <FIG>. The available cell sensitivity subprocess can be started (block 1125i). Begin with a list of all cells (block <NUM>). Have all cells been processed? (block <NUM>). If yes, is list empty? (block <NUM>). Alarm that no cells are available for loading (block <NUM>). If no, is cell loaded? (block <NUM>). Is cell disabled? (block <NUM>). Does cell need calibration? (block <NUM>). Was cell selected for previous load? (block <NUM>). Is cell prone to robot jams? (block <NUM>). Remove cell from list (block <NUM>). Perform neighbor sum subprocess (block <NUM>). Save neighbor sum for this cell and advance to next cell (block <NUM>). Sort available cell list based on neighbor sum, lowest value at the top of the list (block <NUM>). Select the cell at the top of the list as the cell for loading the bottle (block <NUM>). End available cell sensitivity subprocess (block 1125e).

<FIG> is an example neighbor sum subprocess <NUM> shown in <FIG>. A neighbor sum subprocess can be started (block 1316i). Set neighbor sum for this cell to zero (block <NUM>). Is there a loaded cell on the left? (block <NUM>). If yes, add adjacent weight multiplied by the cell criticality of left neighbor to neighbor sum (block <NUM>). If no, is there a loaded cell on the right? (block <NUM>). If yes, add adjacent weight multiplied by the cell criticality of right neighbor to neighbor sum (block <NUM>). If no, is there no cell on either the left or right? (block <NUM>). If yes, add adjacent weight multiplied end factor to neighbor sum (block <NUM>). Is there a loaded cell diagonally to the left? (block <NUM>). If yes, add opposite weight multiplied by cell criticality of left diagonal neighbor to neighbor sum (block <NUM>). If no, is there a loaded cell diagonally to the right? (block <NUM>). If yes, add opposite weight multiplied by cell criticality of right diagonal neighbor to neighbor sum (block <NUM>). Is there no cell either diagonally to the left or right? (block <NUM>). If yes, add opposite weight multiplied by end factor to neighbor sum (block <NUM>). If no, is there a loaded cell two cells to the left? (block <NUM>). If yes, add further weight multiplied by cell criticality of neighbor two cells to the left to neighbor sum (block <NUM>). If no, is there a loaded cell two cells to the right? (block <NUM>). If yes, add further weight multiplied by cell criticality of neighbor two cells to the right to neighbor sum (block <NUM>). If no, is there no cell either two cells to the left or right? (block <NUM>). If yes, add further weight multiplied by end factor to neighbor sum (block <NUM>). If no, end neighbor sum subprocess (block 1316e).

Claim 1:
A method for selecting an empty cell (<NUM>,<NUM>) to place an incoming specimen container (<NUM>) in a test instrument (<NUM>), comprising:
electronically determining and/or obtaining cell availability of cells of a holding structure (<NUM>) in an incubated test chamber (<NUM>) and for each of a plurality of open and available cells:
electronically identifying neighboring cells to each of the plurality of open and available cells;
electronically determining whether each of the identified neighboring cells are occupied or empty and, if occupied, electronically evaluating a time from load of a specimen container held therein to evaluate a test status of the specimen container held therein, wherein evaluating the test status includes identifying whether the specimen container held therein is in a critical test phase based at least in part on the time from load; then
electronically selecting one of the plurality of open and available cells based at least in part on the electronically determining and electronically evaluating; and then electronically directing a loading mechanism (<NUM>,<NUM>) to electromechanically load the incoming specimen container into the selected one of the plurality of open and available cells,
wherein the selecting is carried out to identify the plurality of open and available cells for risk of inducing a false positive in the specimen containers of occupied ones of the identified neighboring cells if loaded with the incoming specimen container.