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Linearstressand buckling analysesofNb-1Zr/C-103 AMTECcells, mounted in a radioisotope generatorcone guration, are performed using e nite element analysis software. The stress analyses indicated that the total induced VonMisesstressesinthestructuralsupportmembersofthecellswillnotexceed86%ofthetemperature-dependent yield stresses of their respective materials. The buckling analyses indicated the need to add ribs to reinforce the cell wall and to decrease the pressure of the inert cover gas present in the generator during launch to 125 kPa. The total mass of the ribbed Nb-1Zr/C-103 cell is 171.5 g, and its specie c mass at the predicted maximum electric power of 8.0 W e is 21.3 g/We.

Refractory alloys are being considered as structural materials in multitube, vapor-anode alkali metal thermalto-electric conversion (AMTEC) cells for future use in radioisotope space electric power systems. In these power systems, the AMTEC cells would operate at a heat source temperature of » 1150 K and a radiator temperature of » 550 K, for a 7‐15 year mission lifetime. In addition to high strength, low density, and low brittle-to-ductile transition temperature, suitablematerialsmustbecompatiblewith thesodium working e uid and havelowthermal expansion and low vapor pressure ( 900 K). C-103 (niobium‐10% hafnium‐1% titanium‐0.5% zirconium ) is also suitable, particularly for thecell’ s colderstructurebecause of its higher strength andlowerthermalconductivity.However,thecompatibilityoftheseniobiumalloyswithsodiumattypicaloperating temperatures and in the presence of minute amounts of oxygen (>5‐10 ppm) for up to 15 years needs further evaluation. Despite the limited availability of rhenium, Mo ‐Re alloys, with a rhenium content of 14 ‐45%, are also good choices as structural materials in vapor anode AMTEC cells. However, their relatively higher density and thermal conductivity could lower the cell’ s performance and increase its specie c mass.

The results of performance analyses of a refractory Nb–1Zr/C-103 vapor anode multi-tube alkali-metal thermal-to-electric conversion (AMTEC) cell are presented and discussed. This cell could be used with a radioisotope heater unit to provide electric power from tens to a few hundreds of watts. In the tens of kilowatts electric range, the AMTEC cells could be used with a parabolic solar concentrator or a nuclear reactor heat source. The present cell measures 41.27 mm in diameter and is 125.3 mm high and has eight sodium beta ′′ -alumina solid electrolyte (BASE) tubes, which are connected electrically in series to provide a load voltage in excess of 3 V. The hot structure of the cell, including the hot plate, the BASE tube support plate, the hot plenum wall and conduction stud, the evaporator standoff and porous wick and the side wall facing the BASE tubes, is made of Nb–1Zr. The cell's colder structure, which includes the condenser structure, the interior thermal radiation shield, the casing and wick of the liquid sodium return artery and the side wall above the BASE tubes, is made of C-103. This niobium alloy is stronger and has a lower thermal conductivity than Nb–1Zr, reducing the parasitic heat conduction losses in the cell wall, hence enhancing the cell's performance. The base cell weighs 163.4 g and delivers 7 W e at 17% conversion efficiency and load voltage of 3.3 V (cell specific mass of 23.4 g/W e ). These performance parameters were for TiN BASE electrodes characterized by B =75 A K 1/2 /m 2 Pa and G =50, assuming a BASE/electrode contact resistance of 0.06 Ω cm 2 and a BASE braze structure leakage resistance of 3 Ω. Also, the inner surfaces of the thermal radiation shield and the cell wall above the BASE tubes were covered with low emissivity rhodium. The temperatures of the BASE brazes and the evaporator were below the recommended design limits (1123 and 1023 K, respectively), and the temperature margin was ⩾+20 K to avoid sodium condensation inside the BASE tube, shorting the cell. When high performance electrodes, characterized by B =120 A K 1/2 /m 2 Pa and G =10, were used, the cell's electric power increased to 8.38 W e at 3.5 V, and the efficiency increased to 18.8%, decreasing the specific mass of the cell to 19.7 g/W e without exceeding any of the design temperature limits.

Etude du probleme de circularite dans l'approche philosophique dispositionnelle des concepts/proprietes. Adoptant la forme des propositions biconditionnelles universelles, l'A. examine l'interpretation semantique et la representation syntaxique des proprietes et des relations definies en termes de complexes et de composants.

Anoxic slurry incubations were performed to examine the relationship between mercury methylation rates (MMR) and sulfate reduction rates (SRR) in salt marsh sediments from the southeastern United States. The MMR and SRR were similarly affected by temperature, addition of low-weight molecular organics, and microbial inhibitors. The MMR was at a maximum in the 12 h after inorganic mercury addition. Initial rates of Hg methylation are correlated with SRR. A significantly slower MMR observed after the initial 12 h following inorganic mercury addition suggested that sorption or precipitation reduced the availability of mercury for methylation. The MMR results for various concentrations of inorganic mercury indicate that saturation kinetics occur. Using this kinetic framework, a model for MMR based on SRR and inorganic Hg concentration was developed. This model was then used to predict the MMR reported in temperature and substrate/inhibitor experiments. The model provided a reasonable estimate of MMR observed in the initial 12 h of the slurry incubations. However, the sequestering of inorganic mercury into less reactive pools by sorption to surfaces or incorporation into other phases alters the amount of bioavailable Hg and hence MMR. Future models that assess the bioavailibility of Hg in the sediments must be developed to extend these observations to field sites.

Remettant en doute la position dominante de D. Kaplan concernant le statut des phrases complexes fondees sur la conjonction que, l'A. defend l'idee selon laquelle celles-ci ne sont pas des instruments de la reference directe, mais des phrases quantificateurs. Se proposant de developper une semantique quantificationnelle des phrases avec que, l'A. substitue a l'analyse du contexte physique de l'enonce celle de la notion de non-demonstration de la non-reference du locuteur, d'une part, et definit les proprietes de l'intention perceptive et de l'intention descriptive du locuteur au fondement de sa semantique, d'autre part

Melorheostosis is an uncommon disorder characterized by soft tissue contractures and sclerosis of bone. The sclerosis appears to flow along the long axis of the bone, akin to candle wax dripping down one side of a candle. Numerous reports of lower extremity involvement exist, but there are few detailed reports of melorheotosis involving the hand. This condition is benign but slowly progressive and can usually be managed conservatively. Loss of function of the hand from swelling, pain, or stiffness, however, may necessitate operative intervention. Two recent cases prompted a review of the literature relating to melorheostosis and the hand.

Soulevant la question de l'objet et des conditions de l'analyse philosophique, de l'analyse informative et de l'analyse scientifique, l'A. se propose de resoudre le paradoxe de l'analyse dans sa forme canonique, en evitant de faire reference a la notion de concept, et definit les elements de la structure dans la quelle s'inscrit sa reponse: 1) l'affirmation selon laquelle il existe des proprietes et des relations complexes, 2) la defense d'une theorie des propositions structurees fondee sur l'interpretation semantique de la structure interne des phrases, 3) l'affirmation de la competence linguistique des mots et des categories

This laboratory has shown that age-related vestibular ganglion cell loss does not occur in the Wistar rat as it does in humans. However, in that study, intracellular changes were evident. The purpose of the present study was to quantitate some of these changes. The volume densities of mitochondria, rough endoplasmic reticulum (RER), Golgi apparatus, and aging pigment, as well as the diameter of the vestibular ganglion cells, of young (3 to 5 months) and old (24 to 31 months) female Wistar rats were determined by electron microscopy and stereological techniques. The data show a significant decrease in the volume densities of mitochondria (11.4%), Golgi apparatus (8.1%), and RER (8.9%), a significant increase in aging pigment (327%), and no change in mean profile diameter. These results suggest a decreased capacity for oxidative metabolism and protein synthesis that may reflect a decrease in the number of hair cells innervated by each ganglion cell and/or in the number of central connections. In either case, these findings suggest impaired metabolic and functional capabilities.

Though there is significant disagreement among philosophers as to the nature of propositions, there is significant agreement as to what philosophical roles propositions are supposed to play. Hence, it is best to explain what propositions are by saying what they are supposed to do. It seems clear that sentences in some sense encode information and that two sentences of the same or different languages may encode the same piece of information. Perhaps “Snow is white” and “Schnee ist weiss” is an example of the latter. If we posit the existence of propositions, they can be identified with pieces of information encoded by sentences; and we can say that the above two sentences express the same proposition. Sentences are true or false in virtue of encoding the information, and hence expressing the propositions, that they do. Hence, propositions are sometimes called the primary bearers of truth and falsity, since sentences are derivatively true or false in virtue of expressing the proposition that they do. Propositions are also thought to be the bearers of modal properties, like being necessary or possible. Further, thinking agents are thought to bear various cognitive relations to propositions: they are the things we believe, doubt, assume, and deny. Related to this latter point, and turning now more to philosophy of language, sentences like “Frege believes that arithmetic reduces to logic” assert that there is a relation, believing, between Frege and the proposition that arithmetic reduces to logic, which is designated by “that arithmetic reduces to logic.” Propositions are also thought to be designated by other expressions, such as “Goldbach’s conjecture” and “what John just said.” Hence, sentences like “What John said entails Goldbach’s conjecture” and others suggest that propositions can stand in relation to each other (entailment) and possess a variety of properties. In addition, many believe that perceptual experiences have accuracy conditions: they can represent the way the world is around us accurately or inaccurately. Many think that the reason this is so is that perceptual experiences have as their contents propositions. However, even among those who agree on this, there is significant disagreement about the nature of the propositions that are the contents of perceptual experience and whether they can be expressed by sentences of natural languages. Finally, current thinking about propositions was very much influenced by the views of Gottlob Frege and Bertrand Russell in the late 19th and early 20th centuries.

Purpose of review To review the recent literature regarding maternal mortality, especially in developed countries, and to provide suggestions for clinical action addressing the rising trend. Recent findings Worldwide maternal deaths declined over the past 20 years; however, it is unlikely that the United Nations' Millennium Development Goal 5 for a 75% reduction in maternal mortality by 2015 will be achieved. Ninety-nine percent of the annual preventable maternal deaths from complications of pregnancy and childbirth occur in developing countries, particularly sub-Saharan Africa. In developed countries, including the United States, numerous strategies have developed to recognize the factors leading to maternal death and to implement systems' changes allowing interventions. In many cases, maternal death is avoidable but oftentimes a patient is saddled with life-long medical consequences. Near-misses are increasing which place a burden not only on the family but also on the healthcare system and overall community. Summary The United States has a rising trend in maternal deaths. To achieve a reduction within all developed countries there must be coordinated death review activities that investigate every case along with near-misses. Recommendations for changes within the medical system will continue to improve maternal health not only in developed countries but also worldwide.

The quality of a neutron imaging beam directly impacts the quality of radiographic images produced using that beam. Fully characterizing a neutron beam, including determination of the beam’s effective length-to-diameter ratio, neutron flux profile, energy spectrum, image quality, and beam divergence, is vital for producing quality radiographic images. This project characterized the east neutron imaging beamline at the Idaho National Laboratory Neutron Radiography Reactor (NRAD). The experiments which measured the beam’s effective length-to-diameter ratio and image quality are based on American Society for Testing and Materials (ASTM) standards. An analysis of the image produced by a calibrated phantom measured the beam divergence. The energy spectrum measurements consist of a series of foil irradiations using a selection of activation foils, compared to the results produced by a Monte Carlo n-Particle (MCNP) model of the beamline. Improvement of the existing NRAD MCNP beamline model includes validation of the model’s energy spectrum and the development of enhanced image simulation methods. The image simulation methods predict the radiographic image of an object based on the foil reaction rate data obtained by placing a model of the object in front of the image plane in an MCNP beamline model.

Gram-negative pathogens are increasingly resistant to extended-spectrum cephalosporins (ESCs). Using a prospective, case-controlled observational study, we examined the prevalence and the risk factors for development of resistance to ESCs in group I beta-lactamase-producing organisms. Of the 386 isolates of Enterobacter species, Pseudomonas aeruginosa, Citrobacter species, and Serratia marsescens from 340 consecutive patients, 70 (18.1%) were resistant to ESCs; the highest rates of resistance were found among Citrobacter freundii (40.9%), Enterobacter cloacae (31.1%), and Enterobacter aerogenes isolates (18.9%). Patients' prior antibiotic use and the mean number of antibiotics used were significantly greater in association with resistant vs. susceptible isolates. Resistance was associated with prior use of ceftizoxime or cefotaxime (P = .008), ceftazidime (P = .004), and piperacillin (P = .001). Other antibiotics were not associated with resistance. Resistance was less frequent in patients receiving ESCs and an aminoglycoside. We conclude that prior use of ESCs is associated with the isolation of resistant group I beta-lactamase-producing organisms. Concomitant use of an aminoglycoside may decrease this risk.

[1] The primary objective of this work is to synthesize components of benthic flux in the Patos Lagoon coastal zone, Rio Grande do Sul, Brazil. Specifically, the component of benthic discharge flux forced by the terrestrial hydraulic gradient is 0.8 m3 d−1; components of benthic discharge and recharge flux associated with the groundwater tidal prism are both 2.1 m3 d−1; components of benthic discharge and recharge flux forced by surface-gravity wave setup are both 6.3 m3 d−1; the component of benthic discharge flux that transports radium-228 is 350 m3 d−1; and components of benthic discharge and recharge flux forced by surface-gravity waves propagating over a porous medium are both 1400 m3 d−1. (All models are normalized per meter shoreline.) Benthic flux is a function of components forced by individual mechanisms and nonlinear interactions that exist between components. Constructive and destructive interference may enhance or diminish the contribution of benthic flux components. It may not be possible to model benthic flux by summing component magnitudes. Geochemical tracer techniques may not accurately model benthic discharge flux or submarine groundwater discharge (SGD). A conceptual model provides a framework on which to quantitatively characterize benthic discharge flux and SGD with a multifaceted approach.

A growing body of evidence has implicated CD24, a cell-surface protein, as a marker of colorectal cancer stem cells and target for antitumor therapy, although its presence in normal colonic epithelium has not been fully characterized. Previously, our group showed that CD24-based cell sorting can be used to isolate a fraction of murine small intestinal epithelial cells enriched in actively cycling stem cells. Similarly, we hypothesized that CD24-based isolation of colonic epithelial cells would generate a fraction enriched in actively cycling colonic epithelial stem cells (CESCs). Immunohistochemistry performed on mouse colonic tissue showed CD24 expression in the bottom half of proximal colon crypts and the crypt base in the distal colon. This pattern of distribution was similar to enhanced green fluorescent protein (EGFP) expression in Lgr5-EGFP mice. Areas expressing CD24 contained actively proliferating cells as determined by ethynyl deoxyuridine (EdU) incorporation, with a distinct difference between the proximal colon, where EdU-labeled cells were most frequent in the midcrypt, and the distal colon, where they were primarily at the crypt base. Flow cytometric analyses of single epithelial cells, identified by epithelial cell adhesion molecule (EpCAM) positivity, from mouse colon revealed an actively cycling CD24+ fraction that contained the majority of Lgr5-EGFP+ putative CESCs. Transcript analysis by quantitative RT-PCR confirmed enrichment of active CESC markers [leucine-rich-repeat-containing G protein-coupled receptor 5 (Lgr5), ephrin type B receptor 2 (EphB2), and CD166] in the CD24+EpCAM+ fraction but also showed enrichment of quiescent CESC markers [leucine-rich repeats and immunoglobin domains (Lrig), doublecortin and calmodulin kinase-like 1 (DCAMKL-1), and murine telomerase reverse transcriptase (mTert)]. We conclude that CD24-based sorting in wild-type mice isolates a colonic epithelial fraction highly enriched in actively cycling and quiescent putative CESCs. Furthermore, the presence of CD24 expression in normal colonic epithelium may have important implications for the use of anti-CD24-based colorectal cancer therapies.

Following dramatic reductions between the early 1900s and the early 1980s, the maternal mortality ratio began to rise, reaching a peak of almost 17 maternal deaths per 100,000 live births. Although this number pales in comparison with that found in sub-Saharan Africa and India, the troubling rise in the United States is a surrogate for medical care in general and obstetrical care in particular. Both Healthy People 2010 and the United Nations Millennium Goals were aimed at reducing maternal mortality worldwide. This presentation will review the trends in maternal mortality along with the efforts some jurisdictions, along with the American Congress of Obstetricians and Gynecologists, have taken to address this obstetrical tragedy. Although maternal death is the tip of the iceberg, thousands more women suffer a "near-miss" but survive to deal with lifelong medical consequences. Finally, you will be reminded that each maternal death is not just an isolated medical event but rather it permanently affects an ever-enlarging circle of society.

Revision elbow arthroplasty is a very technically challenging and demanding procedure. The nerves and vessels about the elbow may be scarred and may no longer be in their usual anatomic locations. The bone stock can also be quite minimal leading to difficulties with further implant fixation. Moreover, the soft tissue envelope is easily compromised about the elbow, and this can lead to problems with wound breakdown and infection. Structural allografts can be helpful in trying to reinforce thinned-out bone. However, in some cases the patient may be better served by resection arthroplasty, especially in many cases of infection.

Benthic flux is the rate of flow across the bed of a water body, per unit area of bed. It is forced by component mechanisms, which interact. For example, pressure gradients across the bed, forced by tide, surface gravity waves, density gradients, bed–current interaction, turbulence, and terrestrial hydraulic gradients, drive an advective benthic flux of water and constituents between estuarine and coastal waters, and surficial aquifers. Other mechanisms also force benthic flux, such as chemical gradients, bioturbation, and dispersion. A suite of component mechanisms force a total benthic flux at any given location, where each member of the suite contributes a component benthic flux. Currently, the types and characteristics of component interactions are not fully understood. For example, components may interact linearly or nonlinearly, and the interaction may be constructive or destructive. Benthic flux is a surface water–groundwater interaction process. Its discharge component to a marine water body is referred to, in some literature, as submarine groundwater discharge. Benthic flux is important in characterizing water and constituent budgets of estuarine and coastal systems. Analytical models to characterize selective benthic flux components are reviewed. Specifically, these mechanisms are for the component associated with the groundwater tidal prism, and forced by surface gravity wave setup, surface gravity waves on a plane bed, and the terrestrial hydraulic gradient. Analytical models are applied to the Indian River Lagoon, Florida; Great South Bay, New York; and the South Atlantic Bight in South Carolina and portions of North Carolina.

The primary purpose of this study was to evaluate whether frontal plane (FP) plyometrics, which are defined as plyometrics dominated with a lateral component, would produce similar increases in vertical jump height (VJH) compared to sagittal plane (SP) Plyometrics. Thirty-two junior varsity and varsity high-school basketball players participated in 6 weeks of plyometric training. Players participated in either FP or SP plyometrics for the entire study. Vertical jump height was measured on 3 occasions: preintervention (baseline), at week 3 of preparatory training, and at week 6 of training. Descriptive statistics were calculated for VJH. A 2-way analysis of variance (ANOVA) with repeated measures was used to test the difference in mean vertical jump scores using FP and SP training modalities. Results showed a significant effect over time for vertical jump (p < 0.001). Moreover, a significant time by protocol interaction was noted (p < 0.032). A 1-way ANOVA demonstrated that only the SP group demonstrated improvements over time, in VJH, p < 0.05. The FP group did not improve statistically. The data from this study suggest that FP plyometric training did not have a significant effect on VJH and significant improvement in VJH was seen in subjects participating in SP plyometrics thus reinforcing the specificity principle of training. However, coaches should implement both types of plyometrics because both training modalities can improve power and quickness among basketball players.

Thin films of Cu 2 ZnSnS 4 (CZTS) were fabricated through a combination of chemical bath deposition, ion exchange and sulfurization heat treatment. Scanning electron microscopy was used to study the morphology of the thin films, Auger electron spectroscopy for compositional analysis, X-ray diffraction and Raman scattering for structural characterization, and diffuse reflectance UV-Vis measurements for optical properties. With the method described, compositionally uniform microcrystalline CZTS with kesterite structure and a bandgap of 1.45 eV have been produced, and a preliminary solar cell device was fabricated to demonstrate that this material is applicable in earth-abundant, non-toxic thin film photovoltaics.

Although computerized tomography (CT) is valuable for evaluating head and neck pathology, it can be suboptimal when evaluating the presence or extent of mandibular and maxillary involvement by tumor, infection, or other pathology. The presence of dental restoration artifact, CT gantry positioning problems, and the inability to obtain cross-sectional images will diminish the accuracy of standard CT images. A program, termed either DentaScan™ or multiplanar reformation (CT/MPR), eliminates these problems by processing axial CT scan information to obtain true cross-sectional images and panoramic views of the mandible and maxilla. In this study, DentaScan imagery was used in 26 patients whose mandibles or maxillas were affected by tumor, osteomyelitis, or other pathology. CT scanning with multiplanar reformation proved useful in the precise location, assessment, monitoring, and treatment of various pathologies of the mandible and maxilla. Selected case studies illustrate the therapeutic implications and advantages of this new imaging technique.

Semantics is the discipline that studies linguistic meaning generally, and the qualification ‘formal’ indicates something about the sorts of techniques used in investigating linguistic meaning. More specifically, formal semantics is the discipline that employs techniques from symbolic logic, mathematics, and mathematical logic to produce precisely characterized theories of meaning for natural languages (i.e. naturally occurring languages such as English, Urdu, etc.) or artificial languages (i.e. first-order predicate logic, computer programming languages etc.). Formal semantics as we know it first arose in the twentieth century. It was made possible by certain developments in logic during that period. This article chronicles those developments and how they led to the development of formal semantics.

We report the replication of holographically defined photonic crystals using multistage atomic layer deposition. Low- and high-temperature atomic layer depositions were combined with selective etching to deposit and remove multiple conformal thin films within three-dimensional polymer templates. Using intermediate Al 2 O 3 inverse replicas, temperature- sensitive SU-8 photonic crystal templates were faithfully replicated with TiO 2 and GaP, greatly increasing the dielectric contrasts of the photonic crystals. Optical measurements are in good agreement with the calculated band structures. © 2009 American Institute of Physics.

[1] A generalized analytical model for benthic water flux forced by linear surface gravity waves over a series of layered hydrogeologic units is developed by adapting a previous solution for a hydrogeologic unit with an infinite thickness (Case I) to a unit with a finite thickness (Case II) and to a dual-unit system (Case III). The model compares favorably with laboratory observations. The amplitude of wave-forced benthic water flux is shown to be directly proportional to the amplitude of the wave, the permeability of the hydrogeologic unit, and the wave number and inversely proportional to the kinematic viscosity of water. A dimensionless amplitude parameter is introduced and shown to reach a maximum where the product of water depth and the wave number is 1.2. Submarine groundwater discharge (SGD) is a benthic water discharge flux to a marine water body. The Case I model estimates an 11.5-cm/d SGD forced by a wave with a 1 s period and 5-cm amplitude in water that is 0.5-m deep. As this wave propagates into a region with a 0.3-m-thick hydrogeologic unit, with a no-flow bottom boundary, the Case II model estimates a 9.7-cm/d wave-forced SGD. As this wave propagates into a region with a 0.2-m-thick hydrogeologic unit over an infinitely thick, more permeable unit, the Case III quasi-confined model estimates a 15.7-cm/d wave-forced SGD. The quasi-confined model has benthic constituent flux implications in coral reef, karst, and clastic regions. Waves may undermine tracer and seepage meter estimates of SGD at some locations.

With nearly 80 million baby boomers in the United States just reaching their sixties, the demand for senior-oriented devices and services will explode in the coming years. Managing the increasing health-care costs for such a population requires developing technologies that will allow seniors to maintain active, independent lifestyles. Pervasive computing pervasive computing environments, such as smart homes , bundle assistive technologies assistive technology and specially designed architectural and home furnishing elements provide health-care and well-being services to its residents. However, for such environments to be commercially viable, we require a system that allows technology to be easily utilized and included as it enters the market place. Also we require new technology to be introduced in a plug-and-play fashion, and applications that are developed by programmers, not system integrators. The Gator Tech Smart House, a full-size, free-standing residential home located in the Oak Hammock Retirement Community in Gainesville, Florida, is an example of this kind of assistive environment . It uses the Atlas sensor network platform, an enabling technology that combines a hardware platform and software middleware , making the Gator Tech Smart House a truly programmable pervasive computing space.

Internet users face challenges in evaluating the validity of online information. Such evaluation is not adequately supported by current tools; we outline some of the shortcomings of these tools, including centralization, lack of automation, and lack of user-centrism. We propose a set of design principles to mitigate these shortcomings and introduce ALPACA, A Lightweight Platform for Analyzing Claim Acceptability, which adheres to these design principles. ALPACA provides a graphical means of organizing the user's trust with regard to information claims and sources, as well as tools for examining the trust assumptions of others.

Using atomic layer deposition (ALD), we show that Pt nanoparticles can be deposited on the inner surfaces of carbon aerogels (CA). The resultant Pt-loaded materials exhibit high catalytic activity for the oxidation of CO even at loading levels as low as approximately 0.05 mg Pt/cm2. We observe a conversion efficiency of nearly 100% in the 150-250 degrees C temperatures range, and the total conversion rate seems to be limited only by the thermal stability of the CA support in ambient oxygen. The ALD approach described here is universal in nature, and can be applied to the design of new catalytic materials for a variety of applications, including fuel cells, hydrogen storage, pollution control, green chemistry, and liquid fuel production.

Osteopontin (OPN), a large secreted glycoprotein with an arginine, glycine, aspartate (RGD) motif, can bind and signal through cellular integrin receptors. We have shown previously that OPN enhances neuronal survival in the setting of ischemia. Here, we sought to increase the neuroprotective potency of OPN and improve the method of delivery with the goal of identifying a treatment for stroke in humans. We show that thrombin cleavage of OPN improves its ability to ligate integrin receptors and its neuroprotective capacity in models of ischemia. Thrombin-cleaved OPN is a twofold more effective neuroprotectant than the untreated molecule. We also tested whether OPN could be administered intranasally and found that it is efficiently targeted to the brain via intranasal delivery. Furthermore, intranasal administration of thrombin-treated OPN confers protection against ischemic brain injury. Osteopontin mimetics based on the peptide sequences located either N or C terminal to the thrombin cleavage site were generated and tested in models of ischemia. Treatment with successively shorter N-terminal peptides and a phosphorylated C-terminal peptide provided significant neuroprotection against ischemic injury. These findings show that OPN mimetics offer promise for development into new drugs for the treatment of stroke.

Despite a significant improvement in the US maternal mortality ratio since the early 1900s, it still represents a substantial and frustrating burden, particularly given the fact that - essentially - no progress has been made in most US States since 1982. Additionally, the US Centers for Disease Control and Prevention has stated that most cases are probably preventable. Two disheartening issues within this topic include a gross underestimation of the magnitude of maternal mortality - particularly before 1987, but which likely persists to a lesser degree today - and the continued significant racial disparity in maternal mortality. Explanations for the plateau in maternal mortality include the recent trend of delayed childbearing, with the potential accompanying complications associated with older reproductive age (particularly over 35 years) and multiparity. The impressive increase in multifetal pregnancies related to delayed childbearing and assisted reproductive technology also plays a role. Finally, peripartum cardiomyopathy has become an increasingly recognized source of maternal mortality. Pregnancy-related mortality is largely accounted for by thromboembolic disease, hemorrhage, hypertension and its associated complications, and infection. However, since the inclusion of maternal deaths occurring after 42 days post-delivery as pregnancy related, traumatic injuries - including homicides and suicides - are an alarming source of maternal mortality. An especially important contemporary issue to consider within this topic is cesarean delivery "on maternal request", opponents of which cite concerns not only for immediate morbidity and mortality increased over that associated with a vaginal birth, but also for potential morbidity and mortality associated with future pregnancies. One particularly appealing opportunity to reduce maternal mortality is to recognize, examine, and learn from so-called "near-miss" cases.

The distribution of two distinct populations of basement membrane proteoglycans has been monitored through hair growth development in the rat embryo and subsequent hair growth cycle. An antiserum against a small heparan sulfate proteoglycan uniformly stained the dermal-epidermal junction of embryonic rats throughout the period of hair follicle formation. On the other hand, monoclonal antibodies recognizing a basement membrane-specific chondroitin sulfate proteoglycan only weakly stained 16-d embryo dermal-epidermal junction, but strong staining was associated with hair follicle buds as they developed. Through the hair growth cycle, it was found that the heparan sulfate proteoglycan persisted around the follicles, while the chondroitin sulfate proteoglycan decreased in amount through catagen until it was undetectable at the base and dermal papilla of the telogen follicle. As anagen commenced, expression of the chondroitin sulfate proteoglycan was again demonstrated. It therefore appears that a basement membrane-specific proteoglycan shows variation in its distribution in rat skin, expression correlating with morphogenetic activity in hair follicles. It is possible that this newly described basement membrane component is involved in the complex processes of dermal-epidermal interaction that lead to skin appendage formation and growth.

This paper defines a new, context-driven programming model for pervasive spaces. Existing models are prone to conflict, as it is hard to predict the outcome of interleaved actions from different services, or even to detect that a particular device is receiving conflicting instructions. Nor is there an easy way to identify unsafe contexts and the emergency remedy actions, or for programmers and users to grasp the complete status of the space. The programming model proposed here resolves these problems by improving coordination by explicitly defining the behaviors via context, and providing enhanced safety guarantees as well as a real-time, at-a-glance snapshot of the space's status. We present this model by first revisiting the definitions of the three basic entities (sensors, actuators and users) and then deriving at the definition of the operational semantics of a pervasive space and its context. A scenario is provided to demonstrate both how programmers use this model as well as the advantages of the model over other approaches.

To demonstrate that injecting drug use is a major risk factor of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infection and injecting drug users may be a reservoir of CA-MRSA infection in our community, we conducted a matched case-control study. Cases were CA-MRSA-infected patients at University of California, Davis, Medical Center, Sacramento, CA, from December 1, 2003, to May 31, 2004. Two control groups were community-associated methicillin-susceptible S. aureus (CA-MSSA)-infected patients and a randomly selected uninfected patient group in the same hospital. Controls were matched to cases by age and isolate culture date. One hundred twenty-seven CA-MSSA patients and 381 randomly selected uninfected controls were selected to match the 127 CA-MRSA cases. The adjusted odds ratio of injecting drug use compared with the CA-MSSA group was 2.11 (95% confidence interval [CI], 1.1-4.3) and 4.09 (95% CI, 2.2-7.5) compared with the uninfected group. We suggest that injecting drug use is a significant risk factor for CA-MRSA infection, which could contribute to the increasing prevalence of CA-MRSA in an urban community.