cssi/SciSciGPT-SciSciNet huggingface dataset:
TH‐E‐L100J‐05: A Three‐Dimensional Linear Model for Investigating the Image Quality of Breast Tomosynthesis

Purpose: To build a three dimensional (3D) linear model for breast tomosynthesis in order to investigate the effects of different imagingsystem design parameters on the reconstructedtomosynthesisimage quality. Method and Materials: The 3D model incorporates the detector performance, imaging geometry and reconstruction filters for the filtered backprojection (FBP) method. To validate the model, experiments were performed on a prototype breast tomosynthesissystem equipped with an amorphous selenium (a‐Se) digital mammographydetector. The detector can be operated in full resolution with 85 micron pixel size or binning mode to reduce acquisition time. Twenty—five projection images were acquired with an angular range of ±20°. The images were reconstructed using a slice thickness of 1 mm with 0.085 mm × 0.085 mm in‐plane pixel dimension. The 3D noise power spectrum (NPS) was computed using reconstructed scatter free uniform images and an edge phantom was imaged to measure the in‐plane modulation transfer function(MTF). An ACR mammography accreditation phantom was imaged to demonstrate the effects of detector operation modes and image acquisition geometry, i.e., angular range, on reconstructed image quality. Results: The measured in‐plane MTF and 3D NPS are both in good agreement with the model. Our results showed that both NPS and in‐plane MTF depend on the reconstruction filters and angular range. Increasing angular range helps improve the MTF at low frequencies, resulting in better detection of the large‐area, low‐contrast mass lesions in the phantom. Pixel binning cuts the acquisition time in half at the cost of decreased high frequency response. This results in reduced visibility of small calcification specks. Conclusion: A 3D linear system model for breast tomosynthesis was developed and validated with experimental measurements. The model can be used to predict the effects of system design parameters on reconstructed image quality. *Research sponsored by Siemens AG.
A chelate theory for the mechanism of action of aspirin-like drugs

Two hundred years after the discovery of the pharmaceutical usefulness of aspirin, it and aspirin-like drugs, a family with an ever-increasing number of members, are an indispensable part of modern life. However, the question as to how these drugs work in the body has remained unsettled. It is postulated here that this group of drugs may exert their therapeutic (and adverse) effects by chelating various physiologically important metallic cations in the body. The chelate theory is supported by the vast majority, if not all, of the observations on these drugs made in the past.
Secondary LD Curricula — A Proposed Framework:

This article presents a framework for a model curriculum for secondary learning disabled students. The framework was developed using a three-round Delphi probe of national experts in secondary LD c...
THE DISTRIBUTION WITHIN THE BRAIN OF FERRITIN INJECTED INTO CEREBROSPINAL FLUID COMPARTMENTS : I. Ependymal Distribution

From 10 minutes to 3½ hours after the intraventricular injection into rats of 15 to 100 mg of ferritin, an appreciable fraction of the protein, visualized electron microscopically, traverses the ependymal epithelium by diffusing along the dense intercellular substance of the luminal open junction and thence, by circumventing discrete intercellular fusions which partition rather than seal the interspace. These partitions shunt additional protein into the cell, where ferritin is transported within pinocytotic vesicles to the lateral and basal plasma-lemma and, presumably, back into the interspace again. The basal interspace is irregularly distended by pools of moderately dense "filler" within which ferritin accumulates. The larger fraction of protein enters the ependyma by pinocytosis and is eventually segregated within membrane-enclosed organelles such as vacuoles, multivesicular bodies, and dense bodies, where the molecules may assume a crystalline packing. As a result of the accumulation of ferritin within these inclusions and within filler substance, only a small amount of protein remains to enter the underlying parenchyma. Presentation of ferritin to prefixed cells leads to a random dispersion of free cytoplasmic ferritin. This artifactual distribution in both prefixed and postfixed cells is concurrent with disruption of cell membranes.
Subjective response during continuous infusion of cocaine

The relationship between the subjective effects induced by IV cocaine injection(s) and cocaine plasma concentrations is complex and difficult to interpret. We designed a study in which bolus loading doses of cocaine followed by 4-hr placebo infusions were compared with the same bolus loading doses of cocaine followed by 4-hr infusions of cocaine calculated to maintain the peak plasma concentrations produced by the bolus. Seven cocaine-using volunteers were successfully studied using a randomized double-blind design, in which self- and observer-rating scales were used to measure drug effects. After the cocaine bolus loading doses, scores for most subjective measures remained elevated when the bolus was followed by a cocaine infusion. In contrast, the subjective responses returned to baseline when the bolus was followed by a placebo infusion. However, self-estimates of the intensity of the cocaine "rush" were not altered by the presence of active cocaine infusions and returned rapidly to baseline.
Diffraction theory and focusing of light by a slab of left-handed material ☆

Abstract A diffraction theory in a system consisting of left- and right-handed materials is proposed. The theory is based upon the Huygens's principle and the Kirchhoff's integral and it is valid if the wavelength is smaller than any relevant length of the system. The theory is applied to the calculation of the smearing of the foci of the Veselago lens due to the finite wavelength. We show that the Veselago lens is a unique optical instrument for the 3D imaging, but it is not a “superlens” as it has been claimed recently.
Midkine Induces Tumor Cell Proliferation and Binds to a High Affinity Signaling Receptor Associated with JAK Tyrosine Kinases

Abstract The G401 cell line derived from a rhabdoid tumor of the kidney secretes the heparin-binding growth factors midkine and pleiotrophin. Both proteins act as mitogens for diverse cells, but only midkine serves as an autocrine mitogen for G401 tumor cells. We show that midkine specifically binds a protein or complex of molecular mass greater than 200 kDa with high affinity (K d = 0.07 ± 0.01 nm). Midkine, but not pleiotrophin, stimulates tyrosine phosphorylation of several cellular proteins with molecular mass of 100, 130, and 200+ kDa. Upon midkine binding, the midkine-receptor complex associates with the Janus tyrosine kinases, JAK1 and JAK2. MK stimulates tyrosine phosphorylation of JAK1, JAK2, and STAT1α. Our initial characterization of the midkine receptor suggests that midkine autocrine stimulation of tumor cell proliferation is mediated by a cell-surface receptor which in turn might activate the JAK/STAT pathway.
Financial aspects of motor carrier safety inspection performance

This paper investigates the empirical relationships between the safety performances and the financial conditions and management forms of a group of motor carriers. Unlike previous work, we utilize cash flow analyses and random, comprehensive roadside safety inspection results to measure financial status and safety performance, respectively, thus avoiding many criticisms of previous studies.
Helicobacter pylori infection of human gastric epithelial cells induces IL-8 and TNFα, but not TGFβ1 mRNA

Helicobacter pylori (Hp) infection causes gastric ulcers and gastric carcinomas. The mechanisms of these diseases are not known but Hp induction of cytokines is believed to be involved. However, the profile as well as the involvement of cytokines induced by Hp infection is less clear. In the present study, steady state levels of interleukin-8 (IL-8), tumor necrosis factor-α (TNFα) and TGFβ1 mRNA of human gastric epithelial cell lines Kato III, AGS and NCI-87N in response to Hp infection were investigated. The cell cultures were infected with Hp for up to 18 h. Total RNA was extracted and analyzed by reverse transcription-PCR. The three cell lines tested expressed low constitutive levels of mRNA for IL-8 and TNFα. The mRNA levels of IL-8 quickly increased within 2 h in all three cells tested and reached a peak at 4 h following infection with Hp. In contrast, the levels of TNFα after Hp infection increased in only Kato III cells. The other cells, AGS and NCI-87N, responded with minimum increases after Hp infection. The TGFβ1 mRNA was constitutively expressed in both AGS and NCI-87N cells, but Kato III cells expressed only low levels prior to infection. The Hp infection did not increase the levels of TGFβ1 mRNA as well as TGFβ1 secretion in all cells tested. These results indicate that the cytokine response to Hp infection differs according to the cells studied and the response may be linked somewhat to TGF levels of gastric cells.
Functional near-infrared spectroscopy maps cortical plasticity underlying altered motor performance induced by transcranial direct current stimulation

Transcranial direct current stimulation (tDCS) of the human sensorimotor cortex during physical rehabilitation induces plasticity in the injured brain that improves motor performance. Bi-hemispheric tDCS is a noninvasive technique that modulates cortical activation by delivering weak current through a pair of anodal-cathodal (excitation-suppression) electrodes, placed on the scalp and centered over the primary motor cortex of each hemisphere. To quantify tDCS-induced plasticity during motor performance, sensorimotor cortical activity was mapped during an event-related, wrist flexion task by functional near-infrared spectroscopy (fNIRS) before, during, and after applying both possible bi-hemispheric tDCS montages in eight healthy adults. Additionally, torque applied to a lever device during isometric wrist flexion and surface electromyography measurements of major muscle group activity in both arms were acquired concurrently with fNIRS. This multiparameter approach found that hemispheric suppression contralateral to wrist flexion changed resting-state connectivity from intra-hemispheric to inter-hemispheric and increased flexion speed (p<0.05). Conversely, exciting this hemisphere increased opposing muscle output resulting in a decrease in speed but an increase in accuracy (p<0.05 for both). The findings of this work suggest that tDCS with fNIRS and concurrent multimotor measurements can provide insights into how neuroplasticity changes muscle output, which could find future use in guiding motor rehabilitation.
Bootstrapping on the adaptive landscape

Different versions of a gene or of a multigenic system may be essentially equivalent so far as the specific function of the structures which they code for or control is concerned, but very different with respect to their amenability to evolution. The structural features which increase evolutionary amenability are a disadvantage to the organism in terms of energy. Nevertheless, they accumulate in the course of evolution as a consequence of hitchhiking along with the desirable traits whose evolution they make possible. This is the bootstrap principle of evolutionary adaptability. In terms of the adaptive landscape bootstrapping corresponds to populations evolving in such a way that they occupy regions of the landscape which are more amenable to evolutionary hill climbing. The bootstrapping idea has implications for structure-function relations in a number of complex biological information processing systems, including biochemical systems, the immune system, and the brain. Bootstrapping is also discussed in connection with the origin of information processing (the origin of life) and in connection with possible designs for macromolecular computing systems.
International Configuration and Coordination Archetypes for Medium-Sized Firms in Global Industries

The purpose of this study is to determine the basic configuration and coordination patterns for medium-sized firms competing in global industries. Analyzing 126 businesses competing in nine different global industries, five distinct archetypes are identified. The results suggest that selective globalization—in which the firm defines its global strategy around a narrow subset of the value chain—may lead to the most effective outcomes.
Choosing and Sampling Dairy Sires: Future Needs for Better Sampling Methods

Choosing among dairy sires is a two stage process of selection. First, young bulls must be chosen on the promise of their pedigree. Secondly, these young bulls must be progeny tested accurately to perform the second stage of the process of selection. Therefore, any consideration of foreseeable future needs for better sampling methods necessarily must be restricted to those ideas that may be useful in improving the accomplishment of the progeny test. Since the theory of evaluation of the progeny test has been thoroughly developed and can be found in many standard textbooks, my purpose here will be to explore some of the present and future problems and possibilities in application of the progeny test. What types of progeny testing systems will be needed? Why are they needed? Where will they be performed? By whom? How? There are answers to some of these questions, but others must wait for the necessary research.
Chrysophyte cysts as potential environmental indicators

Many Chrysophyte algae produce morphologically distinctive, siliceous, microscopic cysts during a resting stage of their life cycles; these cysts are often preserved in sediments. Scanning electron microscopy and Nomarski optics permit much more detailed observation of these cysts than was heretofore possible. We have used an ecologic and biogeographic approach to study the distribution of cyst forms in sediments and have established that many cyst types are found only in specific habitats, such as montane lakes, wet meadows, ephemeral ponds, and Sphagnum bogs. In the samples we have studied, cysts seem to be most common in fluctuating fresh-water habitats of low to moderate pH and some winter freezing. Numerous taxonomic problems have yet to be resolved. We believe that chrysophyte cysts have the potential to become a useful tool for both modern environmental assessments and paleoecological studies of Cenozoic fresh-water lacustrine deposits.
Effect of action video games on the spatial distribution of visuospatial attention

The authors investigated the effect of action gaming on the spatial distribution of attention. The authors used the flanker compatibility effect to separately assess center and peripheral attentional resources in gamers versus nongamers. Gamers exhibited an enhancement in attentional resources compared with nongamers, not only in the periphery but also in central vision. The authors then used a target localization task to unambiguously establish that gaming enhances the spatial distribution of visual attention over a wide field of view. Gamers were more accurate than nongamers at all eccentricities tested, and the advantage held even when a concurrent center task was added, ruling out a trade-off between central and peripheral attention. By establishing the causal role of gaming through training studies, the authors demonstrate that action gaming enhances visuospatial attention throughout the visual field.
Gradual mechanics-dependent adaptation of medial gastrocnemius activity during human walking

While performing a simple bouncing task, humans modify their preferred movement period and pattern of plantarflexor activity in response to changes in system mechanics. Over time, the preferred movement pattern gradually adapts toward the resonant frequency. The purpose of the present experiments was to determine whether humans undergo a similar process of gradually adapting their stride period and plantarflexor activity after a change in mechanical demand while walking. Participants walked on a treadmill while we measured stride period and plantarflexor activity (medial gastrocnemius and soleus). Plantarflexor activity during stance was divided into a storage phase (30–65% stance) and a return phase (65–100% stance) based on when the Achilles tendon has previously been shown to store and return mechanical energy. Participants walked either on constant inclines (0%, 1%, 5%, 9%) or on a variable incline (0–1%) for which they were unaware of the incline changes. For variable-incline trials, participants walked under both single-task and dual-task conditions in order to vary the cognitive load. Both stride period and plantarflexor activity increased at steeper inclines. During single-task walking, small changes in incline were followed by gradual adaptation of storage-phase medial gastrocnemius activity. However, this adaptation was not present during dual-task walking, indicating some level of cognitive involvement. The observed adaptation may be the result of using afferent feedback in order to optimize the contractile conditions of the plantarflexors during the stance phase. Such adaptation could serve to improve metabolic economy but may be limited in clinical populations with disrupted proprioception.
Tuberculosis Screening Method in Question

HIV infection greatly increases an individual’s risk of developing tuberculosis (TB). Indeed, without TB prophylaxis, 1 in 10 HIV-positive individuals exposed to TB develop active TB disease every year. TB prophylaxis with isoniazid therapy reduces the risk of developing active TB by more than 60% among HIV-positive individuals previously exposed to TB. However, if active TB is present, isoniazid therapy alone can result in resistance to the drug: Isoniazid needs to be combined with other TB medications to cure active TB. In low-resource settings, active TB is often excluded by asking questions in a defined protocol about active TB symptoms (fever, cough, night sweats, and loss of weight loss)—the WHO screen. Rangaka et al. have now evaluated the usefulness of the WHO screen for HIV-positive individuals on antiretroviral therapy (ART). The investigators analyzed the results of TB symptom screening among 1429 HIV-positive persons, of whom 54% were on ART. They compared the WHO screen results with sputum culture from those individuals, which is the gold standard for diagnosing active TB. Contrary to their predictions, asking about symptoms was less sensitive among those on ART as compared with those awaiting ART (24% compared with 48%). If individuals reported symptoms while on ART, they were more likely to have active TB than those awaiting ART (94 versus 80%); however, 60% (76 of 126) of individuals with culture-positive TB had a negative question screening test. Adding body-mass index (BMI) increased the discriminatory ability of the WHO screen in both groups. This finding is unexpected because ART improves immune function, and fighting active TB infection was expected to produce symptoms. Thus, the current recommended WHO protocol for excluding active TB before isoniazid therapy does not perform well, especially among HIV-infected persons on ART. New strategies need to be developed for excluding active TB, including adding BMI and lab values to protocols, but for now, sputum culture—where available—remains a valuable tool. Indeed, clinicians should be aware that patients, especially those on ART, may have active TB that is not excluded by screening for symptoms and use supplementary screening methods accordingly. M. X. Rangaka et al. , Effect of antiretroviral therapy on the diagnostic accuracy of symptom screening for intensified tuberculosis case finding in a South African HIV clinic. Clin. Infect. Dis. , published online 5 September 2012 (10.1093/cid/cis775). [[Abstract]][1] [1]: http://cid.oxfordjournals.org/content/early/2012/09/03/cid.cis775.abstract
A climatology of mesoscale model simulated low-level wind jets over Cook Inlet and Shelikof Strait, Alaska

Abstract Weather in the North Gulf of Alaska is characterized by a high frequency of deep synoptic-scale low-pressure systems, especially during the cold season. The strong pressure gradients of these storms interact with the extremely rugged terrain of the coastal mountains to produce a variety of channeled flows. These surface wind regimes are not well documented in the scientific community, due to the paucity of observations. Modeling of these phenomena in regions of complex terrain is of great interest to those working with hydrodynamic, wave, and pollutant transport models in coastal and shelf areas. Such models, when coupled with ocean and coastal-ecology counterparts, give a broad view of the role surface winds play in shaping local coastal marine ecosystem in this region. This paper presents a climatology of simulated low-level wind jets over the domain of Cook Inlet and Shelikof Strait along Alaska's south-central coast. Daily simulations using the RAMS model were conducted in a 36-h forecast mode for the cold-season period 10/1/03 to 3/31/04. Systematic analysis of the resulting simulated low-level wind field makes it possible to characterize these jets and gap flows in spatial and temporal detail. The comparison between the RAMS winds and the Synthetic Aperture Radar (SAR)-derived winds when available verifies the existence of these wind jets and the capability of the model to simulate these cases. Clearly, the results of a study in this region depend on the fidelity of the model at these scales (O[5 km]). The SAR comparisons attempt to help establish this. From the 6 months of simulations over Cook Inlet and Shelikof Strait, the low-level wind jets are classified into 10 different regimes by location and orientation. These regimes are categorized into four more general groups: cross-channel westerly, easterly, and up and down Inlet flows. The nature of a particular regime is largely a function of pressure gradient orientation and local topography. Jets in the same group have a similar occurrence distribution with time. Some form of jet occurred in the study region almost daily each month of the period, with December 2003 having the highest frequency of wind jets.
Gas sorption in polymers, molecular sieves, and mixed matrix membranes

Gas sorption has been an underutilized technique for characterizing organic–inorganic hybrid (mixed matrix) membranes. Sorption in these membranes, which are composed of rigid inorganic domains, such as zeolites, dispersed in a polymer matrix, should be approximately additive. Sorption in the neat polymers and zeolites were first measured to demonstrate that sorption in mixed matrix membranes is approximately additive in the absence of other effects. Sorption in mixed matrix membranes was demonstrated to be additive. This extends to cases where sorption in one or both phases of the mixed matrix membrane is affected by an outside contaminant. For example, zeolite 4A is extremely hydrophilic and easily affected by contaminants from processing or from the test gases. Zeolite 4A encapsulated within a polymer matrix can still be affected by these same components, and this causes sorption lower than predicted based on that in unaffected polymers and sieves. This sorption analysis has proven to be very important in understanding the permeabilities and selectivities of mixed matrix membranes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4053–4059, 2007
On the inclusion principle for the hierarchical finite element method

The inclusion principle provides a qualitative characterization of the eigenvalues of a matrix. The principle has been shown to apply to systems described by a single Hermitian matrix, the most important of which being the real symmetric matrix. Self-adjoint distributed systems, when discretized by either the classical Rayleigh-Ritz method or by the finite element method, lead to algebraic eigenvalue problems described in terms of two real symmetric matrices. The algebraic eigenvalues problem derived by the classical Rayleigh-Ritz method possesses the embedding feature required by the inclusion principle, but that derived by the finite element method in general does not. This paper demonstrates that the inclusion principle can be extended to discretized systems derived by the hierarchical finite element method.
Dynamics and control of the system of a 2-D rigid circular cylinder and point vortices

The Hamiltonian system of a 2-D rigid circular cylinder dynamically interacting with N point vortices in its vicinity (Shashikanth et al., 2002) is an idealized example of coupled solid-fluid systems interacting in the presence of vorticity and has applications to problems in engineering, such as locomotion of autonomous underwater vehicles, and in nature, such as swimming of fish. The first half of the paper presents simulation results and analysis of the system with N = 1 and N = 2, where the latter case is more relevant to the swimming of fish. The second half of this paper is devoted to theoretical analysis of the time-optimal control of the system. The control input is a bounded external force acting through the cylinder center-of-mass. The maximum principle and its later extensions, in particular those due to Sontag and Sussmann, are applied to this system for the case of the cylinder interacting with a single point vortex to arrive at conclusions regarding characteristics of the time-optimal controller.
Paramecium species ingest and kill the cells of the human pathogenic fungus Cryptococcus neoformans

A fundamental question in the field of medical mycology is the origin of virulence in those fungal pathogens acquired directly from the environment. In recent years, it was proposed that the virulence of certain environmental animal-pathogenic microbes, such as Cryptococcus neoformans, originated from selection pressures caused by species-specific predation. In this study, we analyzed the interaction of C. neoformans with three Paramecium spp., all of which are ciliated mobile protists. In contrast to the interaction with amoebae, some Paramecium spp. rapidly ingested C. neoformans and killed the fungus. This study establishes yet another type of protist-fungal interaction supporting the notion that animal-pathogenic fungi in the environment are under constant selection by predation.
On the use of water in the measurement of solid surface tension

Characterization of surfaces which undergo biological fluid contact is often aided by contact angle analysis. A comparison of solid surface tension evaluation methods, particularly addressing a sessile drop technique including and excluding water as a diagnostic liquid, and one in which the surface itself is equilibrated with water is reported for four materials. A particular non-linear relationship between macromolecular deposition and solid surface tension has been observed in our laboratory and elsewhere. This relationship may not be predicted if surface analysis is performed outside an aqueous environment.
Cross-Coupled Noise Propagation in VLSI Designs

Signal integrity has become a critical issue in the design of high-performance circuits. Noise on a net arises both through propagation of noise from previous stages through the driver gate of the net and through injection of new noise through coupling capacitance with neighboring nets. Typically, propagated noise and injected noise are added linearly to simplify the analysis and increase its efficiency. In this paper, we show that this linear assumption results in a significant underestimation of the noise, due to the non-linear behavior of the driver gate, and hence can lead to many undetected noise failures in the design. Since complete non-linear simulation is too slow for large cell-based designs, we propose a new linear model that accurately captures the non-linear behavior of the driver gate. We propose three iterative methods for computing the model parameters of this linear model. Results are presented to demonstrate the accuracy of the proposed approach on several industrial designs.
Society of Thoracic Surgeons Risk Score predicts hospital charges and resource use after aortic valve replacement.

Objective The impact of Society of Thoracic Surgeons predicted mortality risk score on resource use has not been previously studied. We hypothesize that increasing Society of Thoracic Surgeons risk scores in patients undergoing aortic valve replacement are associated with greater hospital charges. Methods Clinical and financial data for patients undergoing aortic valve replacement at The Johns Hopkins Hospital over a 10-year period (January 2000 to December 2009) were reviewed. The current Society of Thoracic Surgeons formula (v2.61) for in-hospital mortality was used for all patients. After stratification into risk quartiles, index admission hospital charges were compared across risk strata with rank-sum and Kruskal–Wallis tests. Linear regression and Spearman's coefficient assessed correlation and goodness of fit. Multivariable analysis assessed relative contributions of individual variables on overall charges. Results A total of 553 patients underwent aortic valve replacement during the study period. Average predicted mortality was 2.9% (±3.4) and actual mortality was 3.4% for aortic valve replacement. Median charges were greater in the upper quartile of patients undergoing aortic valve replacement (quartiles 1–3, $39,949 [interquartile range, 32,708–51,323] vs quartile 4, $62,301 [interquartile range, 45,952–97,103], P P Conclusions This is the first study to show that increasing Society of Thoracic Surgeons risk score predicts greater charges after aortic valve replacement. As competing therapies, such as percutaneous valve replacement, emerge to treat high-risk patients, these results serve as a benchmark to compare resource use.
Correlating Changes in Body Temperature With Infectious Outcome in Febrile Children Who Receive Acetaminophen

We reviewed the body-temperature patterns of 140 children ages 2 to 24 months who had fever > or = 39.0 degrees C, received acetaminophen 10 to 15 mg/kg, and had their temperatures remeasured 60 to 90 min later. The children comprised three groups: 22 had bacterial meningitis; 59, isolated bacteremia; and 59, nonbacterial febrile illness. Percentages of patients who became afebrile (temperature < 38.0 degrees C) after receiving acetaminophen were not significantly different among the three groups. Differences in mean temperature decrease after antipyretic was given were significant within each group but not between groups. An inverse relation (P < .004) between patient age and magnitude of temperature was revealed by the following formula: degrees C of defervescence = 1.66 - (0.028 x patient age in months). Thus, highly febrile young children with and without invasive bacterial infections who receive a therapeutic dose of acetaminophen experience a significant temperature drop after 60 to 90 min but do not commonly defervesce to an afebrile state. The degree of defervescence is age-dependent and does not distinguish between infectious outcomes.
Accuracy of the conductance catheter for measurement of ventricular volumes seen clinically: effects of electric field homogeneity and parallel conductance

The conductance-volume method is an important clinical tool which allows the assessment of left ventricular function in vivo. However, the accuracy of this method is limited by the homogeneity of electric field the conductance catheter produces and the parallel conductance of surrounding structures. This paper examines these sources of error in volumes seen clinically, The characteristics of electric field within a chamber were examined using computer simulation. Nonconductive and conductive models were constructed and experimental measurements obtained using both single-field (SF) and dual-field (DF) excitation. Results from computer simulations and in vitro measurements were compared to validate the proposed theoretical model of conductance-volume method. The effects of field homogeneity and significance of parallel conductance in volume measurement were then determined. The results of this study show that DF provide a more accurate measure of intraventricular volume than SF, especially at larger volumes. However, both significantly underestimate true volume at larger volumes. In addition, the parallel conductance due to the chamber wall is significant at small volumes, but diminishes at larger volumes. Furthermore, the effect of parallel conductance beyond the chamber wall may be negligible. This study demonstrates the limitations in applying current conductance technology to patients with dilated hearts.
Detection of allele-specific methylation through a generalized heterogeneous epigenome model

Motivations: High-throughput sequencing has made it possible to sequence DNA methylation of a whole genome at the single-base resolution. A sample, however, may contain a number of distinct methylation patterns. For instance, cells of different types and in different developmental stages may have different methylation patterns. Alleles may be differentially methylated, which may partially explain that the large portions of epigenomes from single cell types are partially methylated, and may have major effects on transcriptional output. Approaches relying on DNA sequence polymorphism to identify individual patterns from a mixture of heterogeneous epigenomes are insufficient as methylcytosines occur at a much higher density than SNPs. Results: We have developed a mixture model-based approach for resolving distinct epigenomes from a heterogeneous sample. In particular, the model is applied to the detection of allele-specific methylation (ASM). The methods are tested on a synthetic methylome and applied to an Arabidopsis single root cell methylome. Contact: [email protected]
Detection of Shiga toxin-producing Escherichia coli (STEC) O157:H7, O26, O45, O103, O111, O121, and O145, and Salmonella in retail raw ground beef using the DuPont™ BAX® system

Shiga toxin-producing Escherichia coli (STEC) and Salmonella are food-borne pathogens commonly associated with beef, and reliable methods are needed to determine their prevalence in beef and to ensure food safety. Retail ground beef was tested for the presence of E. coli O157:H7, STEC serogroups O26, O45, O103, O111, O121, and O145, and Salmonella using the DuPont™ BAX® system method. Ground beef (325 g) samples were enriched in 1.5 L of TSB with 2 mg/L novobiocin at 42°C for 18 h, and then evaluated using the BAX® System real-time PCR assays for E. coli O157:H7 and STEC suite, and the BAX® System standard PCR assays for E. coli O157:H7 MP and Salmonella. Samples positive for STEC target genes by the BAX® System assays were subjected to immunomagnetic separation (IMS) and plating onto modified Rainbow Agar O157. Enrichments that were PCR positive for Salmonella were inoculated into RV broth, incubated for 18 h at 42C, and then plated onto XLT-4 agar. Presumptive positive STEC and Salmonella colonies were confirmed using the BAX® System assays. Results of the BAX® System STEC assays showed 20/308 (6.5%) of samples positive for both the Shiga toxin (stx) and intimin (eae) genes; 4 (1.3%) for stx, eae, and O26; 1 (0.3%) for stx, eae, and O45; 3 (1%) for stx, eae, and O103; and 1 (0.3%) for stx, eae, and O145. There were also 3 samples positive for stx, eae, and more than one STEC serogroup. Three (1.0%) of the samples were positive using the BAX® System real-time E. coli O157:H7 assay, and 28 (9.1%) were positive using the BAX® System Salmonella assay. STEC O103 and E. coli O157:H7 were isolated from 2/6 and 2/3 PCR positive samples, respectively. Salmonella isolates were recovered and confirmed from 27 of the 28 Salmonella PCR positive samples, and a portion of the isolates were serotyped and antibiotic resistance profiles determined. Results demonstrate that the BAX® System assays are effective for detecting STEC and Salmonella in beef.
Fats: Production and Uses of Animal Fats

The fatty acid composition of carcass tissues significantly influences the functionality of lipids used in processed and/or rendered products. In lean trim, fat can be either intramuscular (marbling) fat, intermuscular (seam) fat, or subcutaneous fat. Oleic acid is the most abundant fatty acid in the fat tissues of meat-bearing animals. Ingestion of the essential, polyunsaturated fatty acids, linoleic and α-linolenic acids, by livestock species leads to enrichment of these fatty acids in fat depots. Because polyunsaturated fatty acids are extensively hydrogenated in the rumen, their levels are very low in carcass fat and lean trim of cattle, sheep, and goats. Porcine fat can be highly enriched with polyunsaturated fatty acids, as dietary polyunsaturated fatty acids are absorbed largely intact. In ruminants, de novo fatty acid synthesis, elongation, and desaturation account for most of the fatty acids in fat depots. In nonruminants, polyunsaturated fatty acids from dietary sources can contribute more than 10% of fatty acids in carcass tissues. Conjugated linoleic acid (CLA) is produced from the isomerization of polyunsaturated fatty acids by rumen microorganisms, but the concentration of CLA isomers in adipose tissue is less than 2% of total fatty acids. Stearic acid absorbed from the small intestine is at least in part desaturated to oleic acid in intestinal mucosal cells, before distribution to the circulatory system. The concentration of stearic acid in lipids has the greatest effect on lipid melting points, which can be from less than 30 °C in lipids from fat of pigs or Japanese cattle to over 40 °C in fat of sheep and pasture-fed cattle. The relative concentrations of saturated, monounsaturated, and polyunsaturated fatty acids affect the quality and stability of processed products and rendered fats.
Effect of Prolactin on Glomerular Filtration Rate

1. The effect of infusion of ovine prolactin was studied in anaesthetized dogs pretreated with bromocryptine to reduce the release of endogenous prolactin. 2. Prolactin, injected intravenously and also directly into one kidney, resulted in a 12–18% increase in glomerular filtration rate (GFR) by both kidneys. 3. This increased GFR was not associated with any demonstrable changes in whole-kidney blood flow, distribution of intrarenal blood flow, fractional excretion of sodium or osmolar or free-water clearance. 4. We conclude that ovine prolactin produced an increase in GFR not dependent on an increase in whole-kidney plasma flow.
Underrepresented minorities in academic medicine: is Florida better off?

Objectives The state of Florida has experienced challenges recruiting and retaining underrepresented minority faculty in academic medicine, as well as maintaining a population-like balance of minority physicians practicing in the state. We sought to quantify the percentage of practicing minority physicians as compared to the general population of Florida and focus specifically on black, Hispanic, and Asian/Pacific Islander physicians in academic medicine. We hypothesized that because of the diversity of the state, the number of underrepresented minority academic physicians in Florida would be higher than the national average. Methods Data were derived and analyzed from a biennial survey initiated in 2007 that all physicians renewing licenses in Florida are required to complete. Fifty percent of the licensing cohort completes the survey annually. We focused on physician practice demographics and academic employment. Results Blacks make up 15.4% of the state population, 6.4% of practicing physicians, but only 3.9% of academic physicians. Hispanics are 22.8% of the state population, 19.2% of practicing physicians, but only 12.5% of academic physicians. Asians are 2.5% of the state population, 14.4% of practicing physicians, and 12.6% of academic physicians. Whites are 58% of the state population, 52% of practicing physicians, and 65% of academic physicians. Conclusions There is disparity in clinical practice and academic medicine for blacks and Hispanics. Despite the diversity of the state, the disparity of blacks in academic medicine in Florida only marginally exceeds the national average. Asians and Hispanics make up the same percentage of academic physicians, but there are 10 times more Hispanics in the state. More research and programming are needed to further define and arrive at solutions to this problem.
Roosts Used by Maternity Colonies of Silver-Haired Bats in Northeastern Oregon

Ten silver-haired bats ( Lasionycteris noctivagans ) that were pregnant or lactating were radiotracked to cavities in 17 trees. Twenty available trees containing cavities were randomly selected for comparison. I measured 19 characteristics of cavities, trees, and habitat in 0.1-ha plots centered on each tree. Increased insolation and retention of heat, which would particularly benefit maternity colonies, may have been achieved by roosts being high in trees and roost trees being farther from other tall trees and in earlier stages of decay. Protection of nonvolant young from terrestrial predators and newly volant young and adult females from aerial predators may have been provided by roosts located high in trees that retained hard wood and that were distant from trees that could restrict flight to and from the roost. Roost trees were taller, retained more of their tops, and more often protruded above the canopy than available trees, making them conspicuous in the auditory and visual landscape.
Concentration dependence of molal conductivity and dielectric constant of 1-alcohol electrolytes using the compensated arrhenius formalism.

The molal conductivity of liquid electrolytes with low static dielectric constants (es < 10) decreases to a minimum at low concentrations (region I) and increases to a maximum at higher concentrations (region II) when plotted against the square root of the concentration. This behavior is investigated by applying the compensated Arrhenius formalism (CAF) to the molal conductivity, Λ, of a family of 1-alcohol electrolytes over a broad concentration range. A scaling procedure is applied that results in an energy of activation (Ea) and an exponential prefactor (Λ0) that are both concentration dependent. It is shown that the increasing molal conductivity in region II results from the combined effect of (1) a decrease in the energy of activation calculated from the CAF, and (2) an inherent concentration dependence in the exponential prefactor that is partly due to the dielectric constant.
THE RESPONSE TO DIFFERING SELECTION ON PLANT PHYSIOLOGICAL TRAITS: EVIDENCE FOR LOCAL ADAPTATION.

Understanding adaptive evolution to differing environments requires studies of genetic variances, of natural selection, and of the genetic differentiation between populations. Plant physiological traits such as leaf size and water-use efficiency (the ratio of carbon gained per water lost) have been suggested by physiological plant ecologists to be important in local adaptation to environments differing in water availability. In this study, I raised families of Cakile edentula var lacustris derived from a wet-site population and a dry-site population in a common greenhouse environment to determine the degree of genetic differentiation between the two populations and the genetic architecture of the traits. The dry-site population had significantly smaller leaf size and significantly greater water-use efficiency than the wet-site population. I used a retrospective selection analysis to compare long-term selection inferred from these results to measures of phenotypic selection from a field experiment. Both direct measures in the field and the retrospective selection gradients were consistent with the hypothesis that greater water-use efficiency and smaller leaves were adaptive in drier environments. Though the correlation between population means for water-use efficiency and leaf size was negative, the genetic correlation within populations between water-use efficiency and leaf size was positive and thus would be expected to constrain the evolutionary response to selection.
Facilitating Emotional Regulation: The Interactive Effect of Resource Availability and Reward Processing

Abstract Despite a wealth of knowledge on the importance of resource availability and reward processing for emotional regulation, surprisingly little is known about the extent to which these two mechanisms interact. Indeed, while research largely supports a positive association between reward processing and recovering from a negative emotional experience, the research does not make a clear prediction regarding the effect of resource availability on this relationship. In two experiments, we explored the extent to which resource availability impacts the efficacy of reward processing to reduce the aversive emotional experience of anxiety. We manipulated participants' mental resource availability, induced anxiety, and varied exposure to either a rewarding or non-rewarding stimulus. The findings consistently demonstrate an interaction between resource availability and reward processing; specifically, the combination of high resource availability and reward processing facilitated the greatest levels of anxiety reduction. Moreover, this interaction was shown to amplify with the intensity of participants' exposure to the reward stimulus. We discuss the practical contributions of these findings and their generative nature for further clarifying the processes underlying emotional regulation.
Control of the tight rope balancing robot

In this paper, a special type of underactuated robotic manipulator-tight rope balancing robotis-is analyzed, and the unique properties of this type of systems are revealed. The tight rope balancing robot is a two-link underactuated robot, which is a highly simplified model similar to a person balancing on a tight rope. In this work, control schemes are addressed from the views of both linear and nonlinear control theories. Simulations showing the motions of the robot using the control method developed in this paper are presented. These simulations verify the effectiveness of the control scheme.
Abstract B28: Induced expression of Sprouty4 in breast invasive ductal carcinoma cells inhibits ERK MAP kinase and reduces malignant phenotype

Our previous work has identified increased expression of Sprouty4 in 3D models of breast ductal carcinoma in situ (DCIS). Sprouty4 in other systems has been shown to function as a negative regulator of the mitogen activated protein kinase (MAPK/ERK) pathway. We hypothesize that Sprouty4 is an endogenous inhibitor of ERK/MAPK signaling in DCIS, and that its loss or reduced expression is one mechanism by which triple-negative lesions progress toward invasive ductal carcinoma (IDC). Using immunohistochemistry our labs have found that Sprouty4 was highly expressed in some human premalignant breast tissue samples, and that this expression was reduced in malignant triple-negative samples. These results correspond with immunoblot data from our 3D culture model of breast cancer progression in which Sprouty4 expression was higher during DCIS than in the IDC stage. Efficient over-expression of Sprouty4 reduced both MAPK/ERK activity as well as the aggressive phenotype of MCF10.CA1d IDC cells. Immunofluorescence experiments done in IDC cells overexpressing Sprouty4 revealed relocation of E-cadherin back to the cell surface and the restoration of adherens junctions. To determine if these effects were due to changes in MAPK/ERK signaling, IDC cells were treated with MEK162, an allosteric MEK inhibitor. Nanomolar concentrations of drug restored an epithelial-like phenotype similar to that produced by Sprouty4 over-expression. From these data we conclude that Sprouty4 may act to control MAPK/ERK signaling in a subset of DCIS, thus limiting the progression of these premalignant breast cancers. Further, if in vivo data correspond with our in vitro work, this may argue for the investigation of MEK inhibitors as an adjunct treatment in triple-negative disease, where options are limited. Citation Format: Ryan M. Jackson, Ethan J. Brock, Seema Shah, Mansoureh Sameni, Bonnie F. Sloane, Quanwen Li, Raymond R. Mattingly. Induced expression of Sprouty4 in breast invasive ductal carcinoma cells inhibits ERK MAP kinase and reduces malignant phenotype. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Targeting the Vulnerabilities of Cancer; May 16-19, 2016; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(1_Suppl):Abstract nr B28.