bluuebunny/crossref_metadata_2025 huggingface dataset:
Smad7 restricts melanoma invasion by restoring N‐cadherin expression and establishing heterotypic cell–cell interactions in vivo
Authors: DiVito Kyle A. , Trabosh Valerie A. , Chen You‐Shin , Chen Yu , Albanese Chris , Javelaud Delphine , Mauviel Alain , Simbulan‐Rosenthal Cynthia M. , Rosenthal Dean S.
Published: August 2010

The list of transforming growth factor‐beta (TGF‐β)‐related proteins in non‐canonical TGF‐β signaling is growing. Examples include receptor‐Smads directing micro‐RNA processing and inhibitory‐Smads, e.g. Smad7, directing cell adhesion. Human skin grafts with fluorescently tagged melanoma cells revealed Smad7‐expressing cells positioned themselves proximal to the dermal–epidermal junction and failed to form tumors, while control cells readily invaded and formed tumors within the dermis. Smad7 significantly inhibited β‐catenin T41/S45 phosphorylation associated with degradation and induced a 4.5‐fold increase in full‐length N‐cadherin. Cell adhesion assays confirmed a strong interaction between Smad7‐expressing cells and primary dermal fibroblasts mediated via N‐cadherin, while control cells were incapable of such interaction. Immunofluorescent analysis of skin grafts indicated N‐cadherin homotypic interaction at the surface of both Smad7 cells and primary dermal fibroblasts, in contrast to control melanoma cells. We propose that Smad7 suppresses β‐catenin degradation and promotes interaction with N‐cadherin, stabilizing association with neighboring dermal fibroblasts, thus mitigating invasion.
Reproducibility of viscoelastic property and intraocular pressure measurements obtained with the Ocular Response Analyzer
Authors: Kopito Robert , Gaujoux Thomas , Montard Romain , Touzeau Olivier , Allouch Cécile , Borderie Vincent , Laroche Laurent
Published: August 2010

Purpose:  To analyse the reproducibility of corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann‐correlated intraocular pressure (IOPg) and corneal‐compensated intraocular pressure (IOPcc) obtained with the ocular response analyzer (ORA).

Methods:  This is a prospective study, nonmasked, of eight successive examinations with the ORA device in 60 normal eyes. Using 30 eyes (one eye per subject), the reproducibility was assessed by comparing the first series of four examinations to the second four and by calculating the within‐subject coefficient of variation. The correlation and difference with the fellow eye were analysed, respectively.

Results:  The mean values were 10.7 ± 1.8 mmHg, CRF; 10.6 ± 1.6 mmHg, CH; 15.9 ± 3.9 mmHg, IOPg and 16.2 ± 3.7 mmHg, IOPcc. The reproducibility was significantly different for CRF (5.2 ± 5.9%), CH (7.3 ± 8.6%), IOPg (7.7 ± 6.7%) and IOPcc (10.1 ± 8.0%); p < 0.001. Considering the reproducibility, CRF correlated with CH (rs = 0.55; p < 0.001) and showed to be independent of IOPg and IOPcc. The score spread was best for CRF (2.6 ± 1.5 mmHg; 24.0%) compared to IOPg (4.3 ± 1.5 mmHg; 28.1%) and CH (3.1 ± 1.7 mmHg; 29.9%) and worst for IOPcc (5.5 ± 2.5 mmHg; 34.4%). The lowest difference with the fellow eye was observed for CRF (5.0%; p = 0.09). The correlation with the fellow eye was high, especially for IOPcc and CRF (rs > 0.9; p < 0.001) followed by IOPg and CH (rs > 0.8; p < 0.001).

Conclusion:  The ORA device provides reproducible information on viscoelastic properties of the cornea in normal eyes notably CRF and CH. IOPcc was less reproducible. Four measurements per eye were necessary to reach a 10% precision and six for 5%.
Cytokine and chemokine levels in tears from healthy subjects
Authors: Carreño Ester , Enríquez‐de‐Salamanca Amalia , Tesón Marisa , García‐Vázquez Carmen , Stern Michael E. , Whitcup Scott M. , Calonge Margarita
Published: August 2010

Acta Ophthalmol. 2010: 88: e250–e258

Purpose:  There is growing evidence for the existence of an ‘immune tone’ in normal tears. The aim of this study was to determine the levels of a large panel of cytokines and chemokines in tears obtained from healthy subjects. These levels can then serve as baseline values for comparison with patients suffering from ocular surface diseases.

Subjects and Methods:  Nine healthy subjects participated in this study, and normal ocular surface health was documented by the results of a dry eye questionnaire, Schirmer strip wetting, and vital staining of the cornea. Four microliters of tears were collected from each eye and analysed separately with multiplex bead‐based assays for the concentration of 30 cytokines and chemokines.

Results:  Twenty‐five cytokines/chemokines were detected. CCL11/Eotaxin1, GM‐CSF, G‐CSF, IFN‐γ, IL‐2, IL‐3, IL‐4, IL‐5, IL‐10, IL‐13, IL‐12p70, IL‐15, CX3CL1/Fractalkine, TNF‐α, epidermal growth factor, and CCL4/MIP‐1β were present at 5–100 pg/ml. IL‐1β, IL‐6, IL‐7A, CXCL8/IL‐8, and CCL2/MCP‐1 were present at 100–400 pg/ml. IL‐1Ra, CXCL10/IP‐10 and vascular endothelial growth factor were present at more than 1000 pg/ml.

Conclusion:  Multiplex bead‐based assays are convenient for cytokine/chemokine detection in tears. Fracktalkine has been detected in human healthy tears for the first time. The knowledge of cytokine/chemokine concentrations in tears from normal subjects is an important reference for further comparison with patients suffering from ocular surface diseases. Variability in their levels can reflect a phenomenon of potential importance for the understanding of the ocular surface cytokine pattern.
Sulfur isotopic composition of Fe‐Ni sulfide grains in CI and CM carbonaceous chondrites
Authors: BULLOCK Emma S. , McKEEGAN Kevin D. , GOUNELLE Matthieu , GRADY Monica M. , RUSSELL Sara S.
Published: August 2010

Abstract– In situ secondary ion mass spectrometry analyses of 32S, 33S, and 34S in iron‐nickel sulfide grains in two CI1 chondrites and six CM chondrites were performed. The results show a wider range of both enrichment and depletion in δ34S relative to troilite from the Canyon Diablo meteorite (CDT) than has been observed in previous studies. All data points lie within error of a single mass dependent fractionation line. Sulfides from CI1 chondrites show δ34SCDT from −0.7 to 6.8‰, while sulfide grains in the CM1 chondrite are generally depleted in heavy sulfur relative to CDT (δ34S from −2.9 to 1.8‰). CM2 chondrites contain sulfide grains that show enrichment and depletion in 34S (δ34SCDT from −7.0 to 6.8‰). Sulfates forming from sulfide grains during aqueous alteration on the chondrite parent body are suggested to concentrate light sulfur, leaving the remaining sulfide grains enriched in the heavy isotopes of sulfur. The average degree of enrichment in 34S in CM chondrite sulfides is broadly consistent with previously suggested alteration sequences.
Sulfide‐rich metallic impact melts from chondritic parent bodies
Authors: SCHRADER Devin L. , LAURETTA Dante S. , CONNOLLY jr. Harold C. , GOREVA Yulia S. , HILL Dolores H. , DOMANIK Ken J. , BERGER Eve L. , YANG Hexiong , DOWNS Robert T.
Published: August 2010

Abstract– Sacramento Wash 005 (SaW) 005, Meteorite Hills 00428 (MET) 00428, and Mount Howe 88403 (HOW) 88403 are S‐rich Fe,Ni‐rich metal meteorites with fine metal structures and homogeneous troilite. We compare them with the H‐metal meteorite, Lewis Cliff 88432. Phase diagram analyses suggest that SaW 005, MET 00428, and HOW 88403 were liquids at temperatures above 1350 °C. Tridymite in HOW 88403 constrains formation to a high‐temperature and low‐pressure environment. The morphology of their metal‐troilite structures may suggest that MET 00428 cooled the slowest, SaW 005 cooled faster, and HOW 88403 cooled the quickest. SaW 005 and MET 00428 contain H‐chondrite like silicates, and SaW 005 contains a chondrule‐bearing inclusion that is texturally and compositionally similar to H4 chondrites. The compositional and morphological similarities of SaW 005 and MET 00428 suggest that they are likely the result of impact processing on the H‐chondrite parent body. SaW 005 and MET 00428 are the first recognized iron‐ and sulfide‐rich meteorites, which formed by impact on the H‐chondrite parent body, which are distinct from the IIE‐iron meteorite group. The morphological and chemical differences of HOW 88403 suggest that it is not from the H‐chondrite body, although it likely formed during an impact on a chondritic parent body.
Tubular symplectic inclusions in olivine from the Fukang pallasite
Authors: STEVENS Michael R. , BELL David R. , BUSECK Peter R.
Published: August 2010

Abstract– Olivine from the Fukang meteorite, like that from many other pallasites, contains distinctive arrays of parallel, straight, tubular inclusions. They differ in their extension and linearity from those in terrestrial olivines. They comprise approximately 1% of the total volume. Most have lens‐shaped cross‐sections, but some are rounded. The major axis of the lens‐shaped inclusions is rigorously oriented along olivine [001], and the rounded ones lie along olivine [010] and a few along [100]. The linear nature and orientations of the inclusions suggest that they nucleated on screw dislocations, perhaps formed through shock triggering. High‐resolution transmission electron microscopy (TEM) and energy‐dispersive x‐ray spectroscopy show that the inclusions consist of symplectic intergrowths of chromite, diopside, and silica that appear to have formed by exsolution from the host olivine. The symplectites consist of chromite lamellae with approximately 35‐nm spacings that grew outward from a central plane, with interstitial diopside and silica. Contrast modulations having an average spacing of 4.4 nm occur within the chromite lamellae. Using a reaction‐front model, we estimate that exsolution occurred over a period of 30 to 100 min, suggesting rapid cooling at high temperature. The crystallographic observations and inferences on growth rate are consistent with the hypothesis that the inclusions nucleated during heating following dislocation formation in a shock event, perhaps concurrent with that proposed to have disrupted the pallasite parent body.
Melt‐bearing impactites (suevite and impact melt rock) within the Gardnos structure, Norway
Authors: KALLESON Elin , DYPVIK Henning , NILSEN Odd
Published: August 2010

Abstract– Melt‐bearing impactites dominated by suevite, and with a minor content of clast‐rich impact melt rock, are found within the central part of the Gardnos structure. They are preserved as the eroded remnants in the relatively small complex impact structure with a present diameter of 5 km. These rocks have been mapped in the field and in the Branden drill core, and described according to mineralogy/petrology, including matrix, litho clast, and melt content, as well as geochemistry. Based on our extensive field mapping, a simple 3‐D model of the original crater was constructed to estimate tentative volumes for the melt‐bearing impactites. The variations in lithic and melt fragment content and chemistry of suevite matrix can mostly be explained by incorporation of mafic rocks into a dominant mixture of granitic, gneissic, and quartzitic target rocks, reflecting mixing of material from different parts of the crater. Melt fragments within suevite occur with a variety of shapes and textures, probably related to different original target rock composition, to the various temperatures the individual fragments were subjected to during the impact event and deposition processes. This study discusses the impact‐related deposits based on a sedimentological approach. Their overall composition and structures indicate dominating gravity flow processes in the final transportation and deposition of the suevite.
Shock and thermal history of Northwest Africa 4859, an annealed impact‐melt breccia of LL chondrite parentage containing unusual igneous features and pentlandite
Authors: JAMSJA Niina , RUZICKA Alex
Published: August 2010

Abstract– Northwest Africa 4859 (NWA 4859) is a meteorite of LL chondrite parentage that shows unusual igneous features and contains widely distributed pentlandite. The most obvious unusual feature is a high proportion of large (≤3 cm diameter) igneous‐textured enclaves (LITEs), interpreted as shock melts that were intruded into an LL chondrite host. One such LITE appears to have been produced by whole rock melting of LL chondrite, initial rapid partial crystallization, and subsequent slow cooling of the residual melt in the host to produce a differentiated object. Other unusual features include mm‐sized “overgrowth objects,” fine‐grained plagioclase‐rich bands, and coarse troilite (≤7 mm across) grains. All these features are interpreted as having crystallized from melts produced by a single transient shock event, followed by slow cooling. A subsequent shock event of moderate (S3) intensity produced veining and transformed some of the pyroxene into the clinoenstatite polytype. Pentlandite (together with associated troilite) in NWA 4859 probably formed by the breakdown of a monosulfide precursor phase at low temperature (≤230 °C) following the second shock event. NWA 4859 is interpreted to be an unusual impact‐melt breccia that contains shock melt which crystallized in different forms at depth within the parent body.
The evolution of the Onaping Formation at the Sudbury impact structure
Authors: GRIEVE Richard A. F. , AMES Doreen E. , MORGAN Joanna V. , ARTEMIEVA Natalia
Published: August 2010

Abstract– The 1.4–1.6 km thick Onaping Formation consists of a complex series of breccias and “melt bodies” lying above the Sudbury Igneous Complex (SIC) at the Sudbury impact structure. Based on the presence of shocked lithic clasts and various “glassy” phases, the Onaping has been described as a “suevitic” breccia, with an origin, at least in part, as fallback material. Recent mapping and a redefined stratigraphy have emphasized similarities and differences in its various vitric phases, both as clast types and discrete intrusive bodies. The nature of the Onaping and that of other “suevitic” breccias overlying impact melt sheets is reviewed. The relative thickness, internal stratigraphic and lithological character, and the relative chronology of depositional units indicate multiple processes were involved over some time in the formation of the Onaping. The Sudbury structure formed in a foreland basin and water played an essential role in the evolution of the Onaping, as indicated by a major hydrothermal system generated during its formation. Taken together, observations and interpretations of the Onaping suggest a working hypothesis for the origin of the Onaping that includes not only impact but also the interaction of sea water with the impact melt, resulting in repeated explosive interactions involving proto‐SIC materials and mixing with pre‐existing lithologies. This is complicated by additional brecciation events due to the intrusion of proto‐SIC materials into the evolving and thickening Onaping. Fragmentation mechanisms changed as the system evolved and involved vesiculation in the formation of the upper two‐thirds of the Onaping.
Petrology and Raman spectroscopy of high pressure phases in the Gujba CB chondrite and the shock history of the CB parent body
Authors: WEISBERG Michael K. , KIMURA Makoto
Published: August 2010

Abstract– High pressure phases majorite, possibly majorite‐pyropess, wadsleyite, and coesite are present in the matrix and in barred olivine fragments in the Gujba CB chondrite. Grossular‐pyrope was also observed in some small inclusions. The CB chondrites are metal‐rich meteorites with characteristics that sharply distinguish them from other chondrite groups. All of the CB chondrites contain impact melt regions interstitial to their chondrules, fragments and metal and a major impact event (or events), on the CB chondrite parent body is clearly a significant stage in its history. We studied three areas interstitial to chondrules and metal in the Gujba CBa chondrite. From Raman spectra, the barred olivine fragments and matrix in these regions have various combinations of olivine and low‐Ca pyroxene, as well as majorite garnet (Mg4Si4O12), a phase that forms by high‐pressure transformation of low‐Ca pyroxene and wadsleyite, a high pressure product of olivine. Compositions of the majorite suggest both majorite and majorite‐pyrope solid solution may be present. The mineral assemblage of majorite and wadsleyite suggest minimum shock pressures and temperatures of ∼19 GPa and ∼2000 °C, respectively. The occurrences of high pressure phases are variable from one area to another, on the scale of millimeters or less, suggesting heterogeneous distribution of shock and/or back transformation to low pressure polymorphs throughout the meteorite. The high pressure phases record a high temperature–pressure impact event that is superimposed onto, and thus postdates formation of, the chondrules and other components in the CB chondrites. The barred chondrules and metal in the CB chondrites are primary materials formed prior to the impact event either generated in an earlier planetesimal scale impact event or in the nebula.
Ar‐Ar ages and thermal histories of enstatite meteorites
Authors: BOGARD Donald D. , DIXON Eleanor T. , GARRISON Daniel H.
Published: August 2010

Abstract– Compared with ordinary chondrites, there is a relative paucity of chronological and other data to define the early thermal histories of enstatite parent bodies. In this study, we report 39Ar‐40Ar dating results for five EL chondrites: Khairpur, Pillistfer, Hvittis, Blithfield, and Forrest; five EH chondrites: Parsa, Saint Marks, Indarch, Bethune, and Reckling Peak 80259; three igneous‐textured enstatite meteorites that represent impact melts on enstatite chondrite parent bodies: Zaklodzie, Queen Alexandra Range 97348, and Queen Alexandra Range 97289; and three aubrites, Norton County, Bishopville, and Cumberland Falls Several Ar‐Ar age spectra show unusual 39Ar recoil effects, possibly the result of some of the K residing in unusual sulfide minerals, such as djerfisherite and rodderite, and other age spectra show 40Ar diffusion loss. Few additional Ar‐Ar ages for enstatite meteorites are available in the literature. When all available Ar‐Ar data on enstatite meteorites are considered, preferred ages of nine chondrites and one aubrite show a range of 4.50–4.54 Ga, whereas five other meteorites show only lower age limits over 4.35–4.46 Ga. Ar‐Ar ages of several enstatite chondrites are as old or older as the oldest Ar‐Ar ages of ordinary chondrites, which suggests that enstatite chondrites may have derived from somewhat smaller parent bodies, or were metamorphosed to lower temperatures compared to other chondrite types. Many enstatite meteorites are brecciated and/or shocked, and some of the younger Ar‐Ar ages may record these impact events. Although impact heating of ordinary chondrites within the last 1 Ga is relatively common for ordinary chondrites, only Bethune gives any significant evidence for such a young event.
Diogenites as polymict breccias composed of orthopyroxenite and harzburgite
Authors: BECK Andrew W. , McSWEEN Jr. Harry Y.
Published: August 2010

Abstract– A few relatively unbrecciated olivine‐rich diogenites consist of an equilibrium assemblage of olivine and magnesian orthopyroxene (harzburgite). More common diogenites with smaller amounts of olivine are breccias containing two distinct orthopyroxenes—one magnesian and one ferroan. These diogenites are mixtures of a harzburgite lithology that is more magnesian, with the “normal” orthopyroxenite lithology that is ferroan and may contain small amounts of plagioclase. Both lithologies likely formed by fractional crystallization in multiple plutons emplaced within the crust of asteroid 4 Vesta. Minor element trends in orthopyroxenes indicate that these plutons exhibited a range of compositions. We propose a revised taxonomy for the HED (howardites, eucrites, and diogenites) suite where all ultramafic samples are referred to as diogenites. Within this group, the prefixes dunitic, harzburgitic, and orthopyroxenitic are used to distinguish diogenites consisting of more than or equal to 90% olivine, olivine + orthopyroxene, and more than or equal to 90% orthopyroxene, respectively. The prefix polymict is used to describe brecciated mixtures of any of these rock types. The recognition that olivine is a significant phase in some diogenites is consistent with spectral interpretations of olivine in a deeply excavated crater on Vesta, and has important implications for the bulk composition and petrogenesis of that body.
Managing the Form, Function, and Fit of DESIGN
Authors: Dumas Angela , Mintzberg Henry
Published: September 2010

HOW A COMPANY understands and organizes design activities can have a profound impact on innovation. To conceptualize this notion, four models are defined, each of which describes how firms address the issues of form, function and fit. One of these – Cooperative Design – holds special promise for innovation because it engages managers as valuable “silent designers” responsible for integrating the many components that comprise a successful development process.
INFORMATION SYSTEMS DESIGNfor theService Industry
Authors: Best Laurence J.
Published: September 2010

THE EFFECTIVE DESIGN of services is intimately connected to the effective design of information and information access. Laurence Best advocates an “electronic desk” strategy, explaining how the techniques of “windowing,” “choice from summary,” and “save relevant detail” provide comprehensive support for tasks ranging from responding to customer questions and scheduling workflow to data acquisition and table manipulation.
CONVERGING PERSPECTIVES: Product Development Research for the 1990s
Authors: Sanders Elizabeth B.‐N.
Published: September 2010

THE ENORMOUS NUMBER of product failures indicates that companies need to dramatically improve the research that goes into the development process so results are simultaneously useful (needed), usable (understandable), and desirable (wanted). Elizabeth B.‐N. Sanders believes this will happen when design managers integrate multiple research techniques‐several of which she describes and illustrates‐in a process referred to as “converging perspectives.”
Learning Theory Through Practice: Encouraging Appropriate Learning
Authors: Ashton Philippa
Published: September 2010

IT'S BEEN MORE THAN 10 years since education experts in England called for providing designers with better training in business and management. Design management education initiatives have proliferated, but executives say problems persist. Research indicates that neither stand‐alone business courses nor integrated business‐design studios are effective in improving design management skills. Philippa Ashton delves into the reasons why and offers a new direction, proposing that distilling specific design management outcomes and revamping the education experience will meet those objectives.
Barriers Between Design and Business Strategy
Authors: Filson Anna , Lewis Alan
Published: September 2010

SMALL AND medium‐size organizations have always been less likely to take advantage of design as a business resource. Based on a survey of companies in the United Kingdom, Anna Filson and Alan Lewis have identified many of the strategic, operational, and cultural reasons behind this reality. A hopeful outcome of this research is that the specificity of their insights will help consultants and leaders in professional associations, government agencies, and the academic world better articulate the value of thoughtful design management.
Glass–Ceramics: Engineering Principles and Applications
Authors: Sakamoto Akihiko , Yamamoto Shigeru
Published: August 2010

The history and typical achievements in the development of glass–ceramics are reviewed on the basis of the engineering principles of crystallization in glass and its application. Bulk and surface crystallization phenomena and their practical applications are described as well as the forming process of glass–ceramics. In addition to conventional glass–ceramic materials and processes, novel potentialities of glass–ceramics in next‐generation devices are also indicated. Luminous glass–ceramics for high‐power lighting and display systems, and electrode materials for rechargeable batteries are emphasized. Recent developments on the position‐selective laser crystallization of the glass surface and a glass–ceramic with anomalous thermal expansion are also introduced.
Novel Design for Jaw-Thrust and Head Immobilization Device and Its Successful Testing Using Human Simulator
Authors: Deshpande Girish , Hand Nicholas , Magnusson Jesse , Davis Alexa , Nair Kalyani , Morris Martin
Published: August 2010

Jaw thrust is a common maneuver performed by medical care providers to open and maintain an airway in an unconscious patient. This essential procedure cannot only occupy significant amount of time for the health care provider, and also result in physical discomfort (low back pain) or fatigue, when it is needed for the extended period. A mechanical device can free up the care provider to perform other necessary tasks to manage critically patient and also prevent fatigue of the medical care provider. The aim of this study is to develop a novel mechanical device that can perform jaw thrust on children from 2 years old to 18 years old and maintain the airway open for extended periods of time. The designed jaw thrust device includes a base with an extension arm mounted on the base on each side of patient’s head. The mandible rest is mounted on each extension arm such that it can be positioned underneath the patient’s jaw. Chinstrap with rubber tubing is placed on the base on four points across the base such that, jaw thrusting pressure on the mandible rests causes rotational force on the chin straps opening patient’s mouth without substantially tilting patient’s head. The device maintains an airway open for extended time without any continuous attention; it also immobilizes the head in the midline thus maintaining the alignment of cervical vertebrae. Detailed finite element analyses of each of the components were done and a prototype was built for functional evaluation on a patient simulator. The device when tested and applied to a patient simulator in obstructed airway state was able to open the airway, evidenced by cough reflex elicited in response and “airway opened” timestamp noted in the computer attached to the simulator.
Development of a Product for Reducing Orthodontic Treatment Duration
Authors: Ling Jeremy , Tarve Brent , Mao Jeremy J. , Lowe Michael , Gerold Jason
Published: August 2010

The commercialization of university-developed technology is described in this paper, which is predicated on the application of pulsating, low magnitude forces (cyclic forces) to the teeth and surrounding bone as a means of accelerating orthodontic tooth movement. The resulting product is a compact device with an external activator that houses the electrical, mechanical, and energy components that apply cyclical mechanical forces to a mouthpiece that is put in a patient’s mouth.
Disinfection of Male Luer Style Connectors for Prevention of Catheter Related Bloodstream Infections Using an Isopropyl Alcohol Dispensing Cap
Authors: Kennedy James P. , Lasher Richard A. , Solomon Donald , Hitchcock Robert W.
Published: August 2010

Bacterial colonization of needleless injection sites (NISs) frequently results in catheter related bloodstream infections (CRBSIs). Hospitals have instituted protocols aimed at disinfecting NIS prior to access. Furthermore, several manufactures have developed devices that facilitate disinfection of NIS. Despite these steps, the incidence of CRBSI is still alarmingly high. Currently, there is no protocol or device intended to disinfect male luer connectors such as those found on IV tubing that are commonly coupled and decoupled from the NISs. Since these IV tubing connectors directly contact the NIS (which have been repeatedly shown to have varying levels of bacterial colonization), it is highly likely that they, too, will have varying levels of contamination. In order for disinfection of the NIS to be effective, the IV tubing connector must also be disinfected. Our design goal was to develop a device that could be used to disinfect a male luer style connector without allowing antiseptic into the inner lumen of the male luer. We designed a three component system that utilizes a silicone sealing cone to seal the male luer, a reservoir foam that holds 70% isopropyl alcohol (IPA), and a reaction force foam that increases the seal pressure of the sealing cone while the reservoir foam is compressed delivering the IPA to the outside surface of the male luer post. Sealing cone geometry was optimized using a custom built seal pressure test apparatus. Reservoir and reaction force foam functional parameters were assessed using an Instron test apparatus. A two phase compression stroke was designed into the device to allow for sealing and dispensing of IPA. An IPA transfer test was used to assess the transfer of disinfectant from the reservoir foam to a liquid filled male luer connector (modeling an IV tubing connector). No disinfectant was found to be transferred from the device to the inner lumen of the IV tubing connector model (n=30). To test the efficacy of the device on reducing bacterial count on the male luer, a disinfection study was performed using the optimized device. Male luers were immersed in bacterial suspensions of S. aureus, S. epidermis, P. aerginosa, and E. coli. A 4 log reduction compared with a positive control was found in each sample treated with our disinfection cap (n=120). In conclusion, we developed a device that effectively delivers an antiseptic to a male luer style connector without leaking any antiseptic to the inner lumen of the luer post
The Evolution of the External Left Ventricular Assist Device
Authors: Soroff Harry , Rastegar Jahangir
Published: August 2010

External counterpulsation is a noninvasive method of applying external pressures to vascular beds of the lower extremities synchronous with the cardiac cycle. Numerous animal experiments and a number of clinical trials have been conducted over the years in patients with various forms of cardiac disease to evaluate the effectiveness of external counterpulsation. The external counterpulsation machines (known as ECP and EECP machines) are currently widely available for use in the treatment of angina by applying positive pressure to the lower extremities during cardiac diastole to increase coronary flow. External counterpulsation has also been shown to be capable of perfusing the ischemic myocardium following an AMI and of assisting the failing left ventricle in patients with CHF. In these applications, positive pressure is applied externally to the lower extremities during cardiac diastole and negative pressure during cardiac systole so as to increase coronary flow and reduce the work of the heart. This paper provides a review of the developments in the area of external counterpulsation and the related devices. The paper also reviews the experimental evidence that provides the scientific basis for the design of a device now under development and called external left ventricular assist device (XLVAD) that should provide effective support of the left ventricle of a patient in congestive heart failure or following an AMI. The evolutionary development of the external counterpulsation devices into the XLVAD is presented in detail. The clinical and mechanical advantages as well as the shortcomings of each device are described.
Design of a Wearable Fingertip Haptic Braille Device
Authors: Saadeh Mohammad , Trabia Mohamed , Shen Yantao , Fadali Sami
Published: August 2010

Existing technologies and devices have facilitated the interaction of the blind or visually impaired (BVI) with their surroundings. However, reading remains an area where the potential of these technologies is not fully utilized. This work presents preliminary studies for the design of a finger-wearable E-Braille device that will allow the BVI to read electronic documents as they would read any document in Braille. The proposed device is wearable on a single finger on of the distal and middle phalanges (dorsal side). The main elements of the device are electrotactile display and force sensor. The electrotactile display is an electric board containing a matrix of electrodes that sends current to the fingertip for stimulating the touch feeling of a particular Braille character. By sending a sequence of Braille characters to this board, information can be sent to the user of the device through the generated electrotactile feeling. The force sensor is used in a feedback control loop to maintain steady contact pressure between the fingertip and the display board throughout the reading process. The entire finger-wearable E-Braille tactile display device is composed of a housing that can be customized to individual users, a miniature dc motor, mechanical components, and main elements. The initial testing of the proposed device is underway. Preliminary results indicate that the device can provide tactile sensation similar to that of reading a Braille document. The initial assessment of the device usability is underway.
Low Profile, Vibrotactile EMG Feedback Device for Direct Placement on Electrode Patch
Authors: Schroeder Mark , Aalund Whitney M. , Bandara Maduka , Jensen Kirk , Stramer Lyle
Published: August 2010

A novel EMG feedback device has been designed and developed. The device exists in two forms: a trainer version to be used by the general consumer and a stethoscope version that is tailored to be used by a therapist or a clinician. The trainer version was designed and built to have a small form factor for direct placement of the device on a disposable electrode patch, thus eliminating the need for electrode wires. The unique design allows for vibrotactile feedback in addition to standard auditory feedback. The stethoscope version provides a stethoscopelike form factor. The audio output can be either a pure tone or the sound of the EMG signal itself. The electrodes in this version consist of a reusable bar electrode containing two fixed electrodes and a reusable grounding electrode. The stethoscope version allows the user to quickly and easily hear EMG information from various locations of the body. Each of the devices provides users with capabilities and functions not previously available from traditional EMG feedback devices.
Toward the Development of Novel Nitric Oxide Donating Polymeric Materials to Improve the Biocompatibility of Implanted Devices
Authors: Moore Elizabeth , Frost Megan C.
Published: August 2010

Previous studies have shown that many S-nitrosothiols (RSNOs) rapidly degrade, with half-lives from minutes to seconds in aqueous solution [1]. The research presented in this paper presents data that the RSNO 1,3-benzenedinitrosothiol has been relatively stable for over 1 year. This RSNO still releases nitric oxide (NO) when subjected to ultraviolet light and has the same characteristic absorbance peak as a freshly made RSNO. Developing this stable RSNO potentially provides a venue for further investigation into using this NO donor to improve the biocompatibility of implanted optical sensors.
Characterization of Precurved Needles for Use in Distal Tip Manipulation Mechanisms
Authors: Walsh Conor , Franklin Jeremy , Slocum Alexander H. , Gupta Rajiv
Published: August 2010

Precurved needles are used in a variety of medical applications for both passive and active control of instrument position. In one application, the deployment of a precurved stylet from a concentric outer cannula can be used to achieve lateral positioning of the distal tip of the stylet. This paper outlines how the material and geometry of the stylet can be chosen to ensure that it will not yield and thus repeatedly return to its precurved shape when deployed from a cannula. Using this methodology, we calculate the maximum strain for a range of stylet geometries and show that nitinol is required for the stylet material so that it will not plastically deform. Then, 16 stylets of varying diameters (0.508 mm, 0.635 mm, 0.838 mm, and 0.990 mm) and radii of curvature (10 mm, 20 mm, 30 mm, and 40 mm) were manufactured. Experiments were performed with four different diameter cannulas (20, 18, 16, and 14 gauges) to measure the forces required to deploy the stylets from and retract them back inside the cannulas. Retraction forces were measured between 0.3 N and 13.9 N, and deployment forces were measured between 0.2 N and 7.0 N. For a given cannula, it was found that force increases as the stylet diameter increases and as the bend radius decreases.
Fuzzy-Based Collaborative Modular Architecture for Medical Device Design and Development
Authors: Aguwa Celestine , Monplaisir Leslie
Published: August 2010

The purpose of this project is to develop a modular architecture framework for the design and manufacture of medical devices. This modular framework aims to incorporate design variables and criteria that are unique to the medical domain to facilitate reliable operation, easier maintenance, and faster product development time. Central to this research effort is the need for inputs from the range of stakeholders. The specific goals for this effort are to determine design criteria by collaborating with users and manufacturers of medical equipment and literature search, to translate user inputs to specific design targets, to develop a preliminary modular design framework using multicriteria optimization methods, and to test a preliminary modular architecture using a simple medical device such as a glucometer. The importance of the research with respect to its application in the medical arena can be very significant. With the product interaction with humans, both on the manufacturing level and the user level, the issue of safety is paramount. Some of the other significant contributions are in the improvement of the following: product quality and reliability, product life cycle issues, and an enabler for the medical community.
Covalent Linking of pH-Sensitive Dye to Fumed Silica
Authors: Nielsen Matthew , Frost Megan C.
Published: August 2010

Measuring the blood gases of patients in the intensive care unit or undergoing major surgical procedures in real time would help healthcare providers diagnose and manage base excess and base deficient disorders. Optical fibers provide a platform upon which an intravascular blood gas sensor may be built and has been by various companies. Unfortunately, thrombosis on the sensor surface interferes with the blood gas measurements and also poses the risk of creating emboli. Nitric oxide inhibits platelet adhesion and activation, which can reduce thrombus formation on the sensor surface. An optically based pH sensor is fabricated as a first step to show that nitric oxide can be used with blood gas sensors to reduce thrombosis and not interfere with the measurements. pH sensors fabricated using glass microscope slides suffered from leaching of the dye from the sol-gel matrix. The dye readily leached out when the dye was in its appropriate protonated or deprotonated form. To reduce the leaching of the dye, methods of covalently linking the dye to fumed silica have been investigated, and one is presented here.
Thorax Model for the Studies of Hemodynamic Monitoring by Implanted Devices
Authors: Lin Jingying , Allen Tadashi , Patterson Robert , Benditt David , Hsiung Hsiang , Zhang Jie
Published: August 2010

Impedance incorporated implanted device provides a unique approach to monitor hemodynamics. The challenge of the use of this method is the optimization of electrode configurations. To alleviate this issue, a 3D thorax model is presented in this study. The model was developed from CT images of a patient, covering from the neck to the lower abdomen. A MATLAB-based program was developed and used to delineate different tissues/organs. The model contains 467 layers and 37 different types of tissues. Each layer had 262,144 pixels with a resolution of 1.0×1.0 mm2, approximately 122×106 pixels (voxels) in total. This high-resolution model can be used as a virtual phantom to optimize electrode configuration for the monitoring of hemodynamics by an implanted device.
Online Artifact Subtraction for Concurrent Neural Recording During Ongoing Electrical Stimulation
Authors: Chernyy Nick , Gluckman Bruce J.
Published: August 2010

Feedback-control has been proved to be advantageous in various technical fields and is likely to increase the performance of electrical neural interface devices. The control algorithms in such a device will rely on metrics of neural activity, thereby necessitating their differentiation from artifacts caused by electrical stimulation. We demonstrate an efficient algorithm for determining the relationship between the electrical stimulus current waveform and the recorded artifact potential, or transfer function. This facilitates online stimulus artifact subtraction and concurrent neural recordings during electrical stimulation. Furthermore, we demonstrate significant changes in this transfer function, in vivo, that occur on time scales of hours and are indicative of changes in the electrical properties of neural tissue. Tracking these variations is paramount for the successful implementation of a feedback-enabled neural control system.
Visual Feedback Automation for ICSI With Rotationally Oscillating Drill (Ros-Drill©)
Authors: Diaz Jhon F. , Olgac Nejat , Karzar-Jeddi Mehdi , Fan Tai-Hsi
Published: August 2010

Intracytoplasmic sperm injection has attracted research interest from both biological and engineering groups. The technology is constantly evolving to perform this procedure with precision and speed. One such development is the contribution of this paper. We focus on a relatively recent procedure called Ros-Drill© (rotationally oscillating drill), of which the early versions have already been effectively utilized for the mice. Here, we present a procedure to automate a critical part of the operation: initiation of the rotational oscillation. Visual feedback is used to track the pipette tip. Predetermined species-specific penetration depth is successfully utilized to initiate the rotational oscillation command. Penetration-depth-based decisions concur with our earlier curvature-based approach.
Effect of Preservation Period on the Viscoelastic Material Properties of Soft Tissues With Implications for Liver Transplantation
Authors: Ocal Sina , Ozcan M. Umut , Basdogan Ipek , Basdogan Cagatay
Published: September 2010

The liver harvested from a donor must be preserved and transported to a suitable recipient immediately for a successful liver transplantation. In this process, the preservation period is the most critical, since it is the longest and most tissue damage occurs during this period due to the reduced blood supply to the harvested liver and the change in its temperature. We investigate the effect of preservation period on the dynamic material properties of bovine liver using a viscoelastic model derived from both impact and ramp and hold experiments. First, we measure the storage and loss moduli of bovine liver as a function of excitation frequency using an impact hammer. Second, its time-dependent relaxation modulus is measured separately through ramp and hold experiments performed by a compression device. Third, a Maxwell solid model that successfully imitates the frequency- and time-dependent dynamic responses of bovine liver is developed to estimate the optimum viscoelastic material coefficients by minimizing the error between the experimental data and the corresponding values generated by the model. Finally, the variation in the viscoelastic material coefficients of bovine liver are investigated as a function of preservation period for the liver samples tested 1 h, 2 h, 4 h, 8 h, 12 h, 24 h, 36 h, and 48 h after harvesting. The results of our experiments performed with three animals show that the liver tissue becomes stiffer and more viscous as it spends more time in the preservation cycle.
MD simulations of GaN sputtering by Ar+ ions: Ion-induced damage and near-surface modification under continuous bombardment
Authors: Despiau-Pujo Emilie , Chabert Pascal
Published: September 2010

Results from molecular dynamics simulations of continuous 50–200 eV Ar+ bombardment on wurtzite and zinc blende GaN surfaces are reported. A new analytical bond-order potential, originally developed for growth process studies, is used to investigate the low-energy physical sputtering of GaN compounds. Preferential sputtering of N atoms is initially observed up to 3.5×1015 ions/cm2 fluence, after which the layers reach steady state sputtering. The crystalline structure of the GaN sample does not have a major influence on the sputtering yield due to the rapid amorphization of the top surface after a few hundred impacts. Concentration depth profiles indicate a surface enrichment in gallium with a N/Ga concentration ratio equal to 0.59±0.1 for 100 eV bombardment, in agreement with published experimental studies. For the same conditions, Ga, N, and GaN species represent 25, 60, and 7% of the sputtered products. A significant fraction of those products leave the surface with kinetic energies sufficiently high to damage the passivation layers on sidewalls during etching processes dominated by physical bombardment.
The Spread of Behavior in an Online Social Network Experiment
Authors: Centola Damon
Published: September 2010

Join the Club

An important question for policy-makers is how to communicate information (for example, about public health interventions) and promote behavior change most effectively across a population. The structure of a social network can dramatically affect the diffusion of behavior through a population.
Centola
(p.
1194
) examined whether the number of individuals choosing to register for a health forum could be influenced by an artificially constructed network of neighbors that were signed up for the forum. The behavior spread more readily on clustered networks than on random, poorly clustered ones. Certain types of behavior within human systems are thus more likely to spread if people are exposed to many other people who have already adopted the behavior (for example, in the circumstances where your friends know each other, as well as yourself).
Is the Tide Turning for New Malaria Medicines?
Authors: Wells Timothy N. C.
Published: September 2010

A return to traditional screening methods has rapidly produced a candidate malaria drug.
Development of a
Bacillus subtilis
-Based Rotavirus Vaccine
Authors: Lee Sangun , Belitsky Boris R. , Brinker James P. , Kerstein Kathryn O. , Brown David W. , Clements John D. , Keusch Gerald T. , Tzipori Saul , Sonenshein Abraham L. , Herrmann John E.
Published: September 2010

Bacillus subtilis
vaccine strains engineered to express either group A bovine or murine rotavirus VP6 were tested in adult mice for their ability to induce immune responses and provide protection against rotavirus challenge. Mice were inoculated intranasally with spores or vegetative cells of the recombinant strains of
B. subtilis
. To enhance mucosal immunity, whole cholera toxin (CT) or a mutant form (R192G) of
Escherichia coli
heat-labile toxin (mLT) were included as adjuvants. To evaluate vaccine efficacy, the immunized mice were challenged orally with EDIM EW murine rotavirus and monitored daily for 7 days for virus shedding in feces. Mice immunized with either VP6 spore or VP6 vegetative cell vaccines raised serum anti-VP6 IgG enzyme-linked immunosorbent assay (ELISA) titers, whereas only the VP6 spore vaccines generated fecal anti-VP6 IgA ELISA titers. Mice in groups that were immunized with VP6 spore vaccines plus CT or mLT showed significant reductions in virus shedding, whereas the groups of mice immunized with VP6 vegetative cell vaccines showed no difference in virus shedding compared with mice immunized with control spores or cells. These results demonstrate that intranasal inoculation with
B. subtilis
spore-based rotavirus vaccines is effective in generating protective immunity against rotavirus challenge in mice.