cssi/SciSciGPT-SciSciNet huggingface dataset:
Use of a Mariner-Based Transposon Mutagenesis System To Isolate Clostridium perfringens Mutants Deficient in Gliding Motility

Clostridium perfringens is an anaerobic Gram-positive pathogen that causes many human and animal diseases, including food poisoning and gas gangrene. C. perfringens lacks flagella but possesses type IV pili (TFP). We have previously shown that C. perfringens can glide across an agar surface in long filaments composed of individual bacteria attached end to end and that two TFP-associated proteins, PilT and PilC, are needed for this. To discover additional gene products that play a role in gliding, we developed a plasmid-based mariner transposon mutagenesis system that works effectively in C. perfringens. More than 10,000 clones were screened for mutants that lacked the ability to move away from the edge of a colony. Twenty-four mutants (0.24%) were identified that fit the criteria. The genes containing insertions that affected gliding motility fell into nine different categories. One gene, CPE0278, which encodes a homolog of the SagA cell wall-dependent endopeptidase, acquired distinct transposon insertions in two independent mutants. sagA mutants were unable to form filaments due to a complete lack of end-to-end connections essential for gliding motility. Complementation of the sagA mutants with a wild-type copy of the gene restored gliding motility. We constructed an in-frame deletion mutation in the sagA gene and found that this mutant had a phenotype similar to those of the transposon mutants. We hypothesize that the sagA mutant strains are unable to form the molecular complexes which are needed to keep the cells in an end-to-end orientation, leading to separation of daughter cells and the inability to carry out gliding motility.
Error-rate analysis of the adaptive successive interference canceler for DS/CDMA signals

The adaptive successive interference canceler (ASIC) is a multistage nonlinear detector that sequentially estimates multiple users in a direct-sequence code-division multiple-access (DS/CDMA) system. In order to successfully regenerate the multiple access interference and subtract it from the received signal, the ASIC requires accurate estimates of the users' received amplitudes. In this paper, we analyze the bit-error-rate performance of the ASIC employing a single antenna element in a synchronous DS/CDMA system. Computer simulations verify the accuracy of the analysis, and a numerical example illustrates the sensitivity of the SIC to incorrect amplitude estimates.
Practicing Testability in the Real World

There have been studies both about the concept of testability and how to implement it, for example using test hooks. In spite of its obvious benefits, we still find low adoption of testability concepts. For example, we do not see a lot of bugs requesting a change in a feature because it will become simpler to test it. In this article we present our experiences while applying testability concepts and lay down guidelines to ensure testability consideration during feature planning and design.We lay the groundwork by briefly going over testability concepts. We talk about the typical thought process in a test developer’s mind and present key insights into why practicing testability is hard.We then present real life examples that we have encountered in our career which exhibit how testability considerations could have made our testing simpler. We discuss the impact of testability on design. Building from these examples, we present a checklist for each of the testability principles. Going over this testability checklist helps ensure we think about the core testability principles when testing a particular feature and ultimately simplifies testing and reducing overall costs. We finally present an exercise where we can apply our checklist to a complex event processing component and realize the benefits of applying testability concepts.
Muninn: a Versioning Flash Key-Value Store Using an Object-based Storage Model

While non-volatile memory (NVRAM) devices have the potential to alleviate the trade-off between performance, scalability, and energy in storage and memory subsystems, a block interface and storage subsystems designed for slow I/O devices make it difficult to efficiently exploit NVRAMs in a portable and extensible way.We propose an object-based storage model as a way of addressing the shortfalls of the current interfaces. Through the design of Muninn, an object-based versioning key-value store, we demonstrate that an in-device NVRAM management layer can be as efficient as that of NVRAM-aware key-value stores while not requiring host resources or host changes, and enabling tightly-coupled optimizations. Muninn is also designed to show that versioning can be added to a file system transparently with minimal host-side changes. As a flash key-value store, it achieves better life-time and low read/write amplification by eliminating internal data movements and per-object metadata updates using Bloom filters and hash functions. By doing so, it achieves as few as 1.5 flash page reads per look up and 0.26 flash page writes per insert on average with 50 million 1 KB key-value pairs without incurring data re-organization. This is close to the minimum number of flash accesses required to read and store the 1 KB key-value pairs, thus increasing performance and lifetime of flash media.
Post-Cold War Realism, Liberal Internationalism, and the Third World

The end of the Cold War has been an opportune moment for international relations scholars to examine the explanatory strengths and weaknesses of prevailing theories. Of particular interest has been how well realism and liberal internationalism explains or fails to explain security and nonsecurity issues in the Third World. While some scholars argue that the existing systemic theories are relevant for understanding all states' actions, others argue that they are irrelevant for explaining issues affecting the Third World. Yet still, there are perspectives that argue for entirely new analytical frameworks for understanding Third World issues. The publication of the books by Stephanie G. Neuman, International Relations Theory and the Third World , William Hale and Eberhard Kienle, After the Cold War: Security and Democracy in Africa and Asia , and Raymond L. Bryant and Sinead Bailey, Third World Political Ecology is timely. They offer a new opportunity to assess how well realism and liberal internationalism explain the behavior of Third World states within the context of the international system. This research communication will analyze the arguments in the above texts and conclude with a brief discussion and assessment of the richness of neorealism for understanding security and non-security issues in the Third World.
Fuzzy logic models with improved accuracy and continuous differentiability

One method of obtaining a fuzzy logic model (FLM) for use in process optimization and control involves the fuzzy weighting of many simple, often linear, functions. The method of identifying the fuzzy weighting scheme typically makes use of triangular membership functions and the minimum operator, both of which result in a model with discontinuous derivatives. Alternate methods of model identification that make use of continuously differentiable membership functions and the product operator will be discussed here. These methods result in models that have improved predictive capabilities for smooth, complex processes typical of those found in the semiconductor manufacturing industry. In addition, with continuously differentiable membership functions and the product operator, the FLM will have continuous derivatives. As a result, the operation of algorithms that rely on derivatives obtained from the model will be enhanced. Three types of FLM's and an artificial neural network (ANN) model were obtained for eight different sets of data representing three processes, and the resulting models were compared. The predictive capability of each model was estimated by computing the multiple correlation coefficient, R/sub predict//sup 2/, over a large number of points distributed throughout the input space. For one of the most complex examples studied, a simulated six-input chemical vapor deposition process, the traditional FLM using the minimum operator and triangular membership functions had R/sub predict//sup 2/=-0.43, indicating very poor predictive capability. The fuzzy logic model using the product operator and triangular membership functions had R/sub predict//sup 2/=0.87. The fuzzy logic model using the product operator and piece wise defined quadratic membership functions with continuous first derivatives had R/sub predict//sup 2/=0.92. The ANN model for the same data had R/sub predict//sup 2/=0.73. Similar results were observed for each example presented, indicating appropriately defined FLM's can meet or exceed the modeling capabilities of artificial neural networks for nonlinear, multi-dimensional problems.
Application-level prediction of battery dissipation

Mobile, battery-powered devices such as personal digital assistants and web-enabled mobile phones have successfully emerged as new access points to the world's digital infrastructure. However, the growing gap between device capabilities and battery technology requires novel techniques that extend battery life. Key to the success of such techniques, is our ability to accurately predict the power consumption of a program. In this paper, we investigate the degree to which battery dissipation induced by program execution can be measured by application-level software tools and predicted by a compiler and runtime system. We present a novel technique with which we can accurately estimate whole-program power-consumption for an arbitrary program by composing battery dissipation rates of benchmarks. We empirically evaluate our technique using an iPAQ hand-held device and a number of MiBench and other programs.
False Recognition in Women Reporting Recovered Memories of Sexual Abuse

False recognition--the mistaken belief that one has previously encountered a novel item--was examined in four groups of subjects: women reporting recovered memories of childhood sexual abuse, women who believe that they were sexually abused as children but who cannot recall this abuse (the "repressed" group), women who were sexually abused as children and always remembered the abuse, and women with no history of childhood sexual abuse. Subjects were administered a Deese/Roediger-McDermott paradigm. The results suggest that the recovered-memory group was more prone to false recognition than the other groups. In addition, women reporting recovered and repressed memories showed greater reduction in false recognition across study trials than did other subjects, perhaps reflecting strategic changes in performance.
Alcoholism-related alterations in spectrum, coherence, and phase synchrony of topical electroencephalogram

The objective of present work was to assess differences in spectrum, coherence, and phase synchrony of topical electroencephalogram (EEG) between alcohol-dependent individuals and healthy participants. Surface currents were mitigated by a common average spatial filter. Parametric spectral and coherence estimates obtained for consecutive 0.5s-long EEG fragments were generally lower for alcoholics than for controls while evaluated for low EEG rhythms. Phase synchrony computed for 2.34s-long overlapping EEG fragments was lower for alcoholics than for controls while evaluated in @a"2 and @b"1 rhythms and for specific electrode pairs. Kruskal-Wallis one-way analysis of variance evaluated these alterations as statistically significant.
Calculation of a deuterium double shock Hugoniot from ab initio simulations.

of 0.67 � � � 1.60 gcm 3 . We derive the double shock Hugoniot and compare with the recent laser-driven double shock wave experiments by Mostovych et al. [9]. We find excellent agreement between the two types of microscopic simulations but a significant discrepancy with the laser-driven shock measurements. Single-shock laser experiments on liquid deuterium have probed the equation of state (EOS) up to 340 GPa [1] and have measured a significantly higher compressibility than predicted by standard models like Sesame [2] and by more recent experiments using magnetic drives [3]. The laser-driven experimental findings also disagree with results from first principles simulations [4, 5, 6] and leave only some chemical models in agreement [7, 8]. The EOS is of fundamental importance to our understanding of many physical phenomena such as the Jovian planets, inertial confinement fusion, and pulsed-power produced plasmas. In the recent laser-driven double shock (DS) experiments by Mostovych et al. [9], final pressures of 100-600 GPa have been reached. The results also disagree with the Sesame EOS but agree well with the linear-mixing model [7]. Both models are based on an approximate free energy function constructed from known theoretical limits, e.g., Sesame uses Saha and Thomas-Fermi-Dirac theories for the electronic properties and hard sphere reference systems to incorporate atoms and molecules. The double shock experiments appear to provide an independent confirmation of both the laser-driven single shock results [1] as well as some of the chemical models. Furthermore the findings were interpreted as an indication that the dissociation of molecules makes deuterium more compressible than predicted by microscopic simulations. In this paper, we compare the Mostovych et al. [9] DS results with ab initio simulations from path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD). We give details of the calculation of the secondary shock hugoniot curve from the simulation results. In this calculation, we use either the PIMC results or combine PIMC and DFT data. Both methods yield very similar results. We discuss whether the DS results indicate an increased compressibility for the primary hugoniot curve and therefore support the sin
A multidecadal study of the number of Antarctic icebergs using scatterometer data

Tabular Antarctic icebergs are regularly formed by the separation of massive sections of ice from ice shelves and glaciers. The National Ice Center (NIC) uses a variety of satellite sensors to track large Antarctic icebergs and reports iceberg position,. According to the NIC database, the number of large Antarctic icebergs has been increasing in recent years. A long term analysis of Antarctic iceberg activity based on scatterometer and radiometer data is presented. Our analysis suggests this increase is largely due to improved resources and technological advancements for iceberg tracking. Recent calving events may represent natural variability in iceberg activity. This study identifies some of the advantages and limitations of tracking icebergs using scatterometer data.
Grazing Cow and Calf Responses to Zinc Supplementation

This experiment evaluated weight gain responses to supplemental Zn by cows and calves grazing forage containing less than 20 ppm Zn. One hundred cow-calf pairs in each of 2 years and 120 paird in a third year were pastured together over a 63- to 77-day preliminary period during which cows were exposed to bulls. Each experimental period began in mid-June after bulls were removed and continued for 125 to 154 days. During this period, cattle grazed mature dry forage containing less than 20 ppm Zn and were fed protein supplements with or without added Zn. Estimated Zn intake by each cow-calf pair in the control group ranged from about 140 to 260 mg/pair/day. Daily Zn intake was supplied by forage (100 to 200 mg), basal supplement (32 to 57 mg), water (4 mg), iodized block salt (1 mg) an soil (1 mg). Each cow-calf pair fed the supplement with added Zn received an additional 860 to 900 mg Zn/day. Calves fed Zn gained 6% more (P less than .05) weight (.04 kg/day) between the two groups. Clinical signs of Zn deficiency were not observed in any animals. Conception which occurred before the experimental period, and subsequent calving rates were not affected by Zn supplementation.
An immigration-pressure model of global distributive justice

International borders concentrate opportunities in some societies while limiting them in others. Borders also prevent those in the less favored societies from gaining access to opportunities available in the more favored ones. Both distributive effects of borders are treated here within a comprehensive framework. I argue that each state should have broad discretion under international law to grant or deny entry to immigration seekers; but more favored countries that find themselves under immigration pressure should be legally obligated to fund development assistance for countries that generate immigration pressure. Funding should be subject to conditions of fair and effective use in recipient countries, and should aim at a near-term target of immigration-pressure equilibrium. Equilibrium obtains between two countries when, given appropriate background circumstances, the same proportion of individuals in each manifests a preference to migrate to the other. If meeting the equilibrium target in the short ter...
Polemics, Postmodernism, Immersion, Militarized Space

Hal Foster is Townsend Martin, Class of 1917, Professor of Art and Archaeology at Princeton University. Internationally regarded for his provocative writings on 20th-century art practice, and as an...
How bodies matter: five themes for interaction design

Our physical bodies play a central role in shaping human experience in the world, understandingof the world, and interactions in the world. This paper draws on theories of embodiment - from psychology, sociology, and philosophy - synthesizing five themes we believe are particularly salient for interaction design: thinking through doing, performance, visibility, risk, and thick practice. We intro-duce aspects of human embodied engagement in the world with the goal of inspiring new interaction design ap-proaches and evaluations that better integrate the physical and computational worlds.
Accuracy of imaging technologies in the diagnosis of acute cardiac ischemia in the emergency department: A meta-analysis☆☆☆★

Abstract Study Objective: We sought to quantitatively evaluate the evidence on the diagnostic performance of imaging technologies (including rest and stress echocardiography and technetium-99m sestamibi scanning) for the diagnosis of acute cardiac ischemia and acute myocardial infarction in the emergency department. Methods: We conducted a systematic review and meta-analysis of the English-language literature published between 1966 and December 1998. Both prospective and retrospective studies qualified for the assessment of diagnostic performance. Diagnostic performance was assessed by means of random-effect estimates of test sensitivity, specificity, and the diagnostic odds ratio and was summarized by using summary receiver-operating characteristic curves. Results: Diagnostic accuracy was evaluated in 10 studies of rest echocardiography, 2 studies of dobutamine stress echocardiography, and 6 studies of technetium-99m sestamibi scanning. However, only 3 rest echocardiography and 5 technetium-99m sestamibi studies evaluated patients strictly in the ED setting. Patient populations were often highly selected to represent low- or moderate-risk groups. When limited to ED studies, rest echocardiography showed excellent sensitivity of 93% (95% CI, 81% to 97%) and good specificity of 66% (95% CI, 43% to 83%). The results were similar when all studies were considered, including data from reports of admitted patients and patients sent to the cardiac care unit. There was insufficient literature on stress echocardiography in the ED to properly assess the technology. Technetium-99m sestamibi scanning also showed excellent sensitivity (range, 91.5% to 100%) and good specificity (range, 49.3% to 84.4%) for acute myocardial infarction; for acute cardiac ischemia, the random-effects pooled sensitivity was 89% (95% CI, 73% to 96%), and the pooled specificity was 77% (95% CI, 63% to 87%). Conclusion: For selected low- and moderate-risk patient groups, echocardiography and technetium-99m sestamibi imaging appear to have very good diagnostic performance with a similar sensitivity and specificity profile. More evidence should be accumulated on their performance specifically in the ED setting. [Ioannidis JPA, Salem D, Chew PW, Lau J. Accuracy of imaging technologies in the diagnosis of acute cardiac ischemia in the emergency department: a meta-analysis. Ann Emerg Med. May 2001;37:471-477.]
Localisation of 11β-Hydroxysteroid Dehydrogenase Type 2 in Mineralocorticoid Receptor Expressing Magnocellular Neurosecretory Neurones of the Rat Supraoptic and Paraventricular Nuclei.

An accumulating body of evidence suggests that the activity of the mineralocorticoid, aldosterone, in the brain via the mineralocorticoid receptor (MR) plays an important role in the regulation of blood pressure. MR was recently found in vasopressin and oxytocin synthesising magnocellular neurosecretory cells (MNCs) in both the paraventricular (PVN) and supraoptic (SON) nuclei in the hypothalamus. Considering the physiological effects of these hormones, MR in these neurones may be an important site mediating the action of aldosterone in blood pressure regulation within the brain. However, aldosterone activation of MR in the hypothalamus remains controversial as a result of the high binding affinity of glucocorticoids to MR at substantially higher concentrations compared to aldosterone. In aldosterone-sensitive epithelia, the enzyme 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) prevents glucocorticoids from binding to MR by converting glucocorticoids into inactive metabolites. The present study aimed to determine whether 11β-HSD2, which increases aldosterone selectivity, is expressed in MNCs. Specific 11β-HSD2 immunoreactivity was found in the cytoplasm of the MNCs in both the SON and PVN. In addition, double-fluorescence confocal microscopy demonstrated that MR-immunoreactivity and 11β-HSD2-in situ hybridised products are colocalised in MNCs. Lastly, single-cell reverse transcriptase-polymerase chain reaction detected MR and 11β-HSD2 mRNAs from cDNA libraries derived from single identified MNCs. These findings strongly suggest that MNCs in the SON and PVN are aldosterone-sensitive neurones.
Individual somatic H1 subtypes are dispensable for mouse development even in mice lacking the H1(0) replacement subtype.

DNA in the nuclei of all eukaryotic cells is packaged into repeating units of nucleosomes that form the basic unit of chromatin. Each nucleosome consists of an octamer core containing two molecules of each of the core histones, H2a, H2b, H3, and H4. H1 linker histones bind to the nucleosome core particle and the linker DNA between nucleosomes to facilitate further compaction of chromatin into a 30-nm fiber. Recent studies have shown that the chromatin complex, especially the nucleosome and its modifications, can have a profound influence on transcription (reviewed in references 9 and 26). Although histones are highly conserved proteins, multicellular organisms contain a variety of subtypes exhibiting significant sequence divergence. Among the histone classes, the H1 linker histones are the most divergent group. In mammals, there are at least eight H1 subtypes, including the somatic H1s, H1a to H1e, germ cell-specific H1t and H1oo, and replacement linker histone H10 (11, 24). These subtypes exhibit distinct patterns of expression during differentiation and development (12, 24). The significance of the diversity present within the H1 family is not understood. The genes for H1a through H1e and H1t are tightly linked on mouse chromosome 13 (25). The H10 gene is located on mouse chromosome 15 (2). H10 is the smallest and most divergent member of the H1 family (27). H10 accumulates in quiescent cells and during terminal differentiation and terminal cell division, reaching levels as high as 30% of the total H1 in certain tissues, such as adult liver. Despite the unique properties and developmental regulation of H10, previous studies in our laboratory showed that mice develop normally without H10 (23). Analysis of chromatin from H10-null mice indicated that the level of the somatic H1s, especially H1c, H1d, and H1e, was increased so as to maintain a normal ratio of H1 to nucleosomes in H10-deficient chromatin. In certain tissues, such as adult liver, H1c, H1d, and H1e accounted for 95% of the remaining H1, suggesting that these subtypes are responsible for compensating for loss of H10. The present study was undertaken with the following two experimental objectives: first, to determine whether or not any one of several H1 subtypes is essential for mouse development; second, to determine whether H1c, H1d, or H1e is responsible for compensating for the loss of H10 in H10−/− mice. To achieve the first goal, we generated null mutations in each of the three somatic H1 genes by homologous recombination in embryonic stem (ES) cells and then produced mice lacking each of these individual subtypes. To achieve the second goal, we bred each of these three H1 knockout mice to H10 null mice and ultimately produced H1c/H10, H1d/H10, and H1e/H10 double-knockout mice.
Flexible retrospective selection of temporal resolution in real-time speech MRI using a golden-ratio spiral view order

In speech production research using real-time magnetic resonance imaging (MRI), the analysis of articulatory dynamics is performed retrospectively. A flexible selection of temporal resolution is highly desirable because of natural variations in speech rate and variations in the speed of different articulators. The purpose of the study is to demonstrate a first application of golden-ratio spiral temporal view order to real-time speech MRI and investigate its performance by comparison with conventional bit-reversed temporal view order. Golden-ratio view order proved to be more effective at capturing the dynamics of rapid tongue tip motion. A method for automated blockwise selection of temporal resolution is presented that enables the synthesis of a single video from multiple temporal resolution videos and potentially facilitates subsequent vocal tract shape analysis.
Headcut Erosion in Wyoming’s Sweetwater Subbasin

Increasing human population and intensive land use combined with a warming climate and chronically diminished snowpacks are putting more strain on water resources in the western United States. Properly functioning riparian systems slow runoff and store water, thus regulating extreme flows; however, riparian areas across the west are in a degraded condition with a majority of riparian systems not in proper functioning condition, and with widespread catastrophic erosion of water-storing peat and organic soils. Headcuts are the leading edge of catastrophic channel erosion. We used aerial imagery (1.4-3.3-cm pixel) to locate 163 headcuts in riparian areas in the Sweetwater subbasin of central Wyoming. We found 1-m-the generally available standard resolution for land management-and 30-cm pixel imagery to be inadequate for headcut identification. We also used Structure-from-Motion models built from ground-acquired imagery to model 18 headcuts from which we measured soil loss of 425-720 m3. Normalized by channel length, this represents a loss of 1.1-1.8 m3 m(-1) channel. Monitoring headcuts, either from ground or aerial imagery, provides an objective indicator of sustainable riparian land management and identifies priority disturbance-mitigation areas. Image-based headcut monitoring must use data on the order of 3.3 cm ground sample distance, or greater resolution, to effectively capture the information needed for accurate assessments of riparian conditions.
The “We” Problem in Teaching International Studies

This article addresses the problems that emerge when students in international studies courses approach the subject matter from the perspective of the first person plural. Whether in terms of “we,”“us,” or “our,” many college students choose to adopt a personal perspective in discussions of international affairs. While it is natural for students to base their analysis of international studies on their personal observations and experiences, this inclination to adopt a collective first person approach detracts from the scholarly neutrality toward which students of global studies should aspire. Furthermore, a first person plural approach to course subject matter creates the false impression among students that they are all in agreement over contentious issues of global interactions and the theories employed to study them. The article concludes with suggestions for remedying the “we” problem, and offers advice for instructors who have encountered it in their own classroom.
Interplay of nanoscale domain purity and size on charge transport and recombination dynamics in polymer solar cells.

Charge transport and bimolecular recombination dynamics were correlated with nanomorphology in polymer solar cells. The morphology of poly(diketopyrrolopyrrole-terthiophene) (PDPP3T) and phenyl-C61-butyric acid methyl ester (PC60BM) blend films was modified using different solvent additives namely 1-chloronaphthalene (CN), 1,8-diiodooctane (DIO) and 1,8-octanedithiol (ODT) and their role on steady state and transient optoelectronic properties was investigated. The energy filtered transmission electron microscopy (EFTEM) images showed that additives (e.g. CN and DIO) improved the domain purity which leads to significantly higher short circuit current densities (Jsc). However when the cells were processed with the ODT additive, the fill factor (FF) and open circuit voltage (Voc) decreased dramatically. Films processed with the ODT additive showed a smaller domain size but were more connected compared to films processed using CN and DIO additives. Transient photocurrent analysis indicates faster charge collection in the case of CN and DIO processed solar cells and the slowest charge collection in ODT processed solar cells. Interestingly devices processed with the ODT additive also showed the longest charge carrier recombination lifetime and lowest bimolecular recombination coefficient. This is attributed to the smaller donor domains that are connected with each other to provide a more interconnected and efficient charge transport matrix but longer pathways in ODT films. Such a matrix helped the charge to escape from the donor–acceptor interfaces and thus reduces the bimolecular recombination, while the longer pathway increases the charge collection time. Further insight is provided into the selection of processing conditions to achieve an ideal active layer morphology consisting of domains with higher polymer purity and optimal size that lead to higher Jsc and FF.
Sensitivity analysis of radio architectures employing sample and hold techniques

This paper explores the feasibility of developing the "ultimate goal" of a flexible receiver, comprised of an analogue to digital converter with an antenna as its input. This is done through some analysis which describes the use of simple and hold devices for frequency conversion within a radio. Through the use of a perfect multiplier a model is developed in order that the noise figure of a sample and hold device can be predicted. The results show that sample and hold devices have higher noise figures than mixers and hence their use can give rise to reduced receiver sensitivity. The analysis also demonstrates that their noise figure performance is considerably improved through the use of RF gain and filtering. This demonstrates that the ability to sample at RF can only realistically be achieved with appropriate consideration of the necessary RF gain and selectivity, and thus flexible receivers need programmable filters. Interestingly the paper also concludes that an ideal sampler has an infinite noise figure and is therefore useless.
Generalized flooded agglomerate model for the cathode catalyst layer of a polymer electrolyte membrane fuel cell

Abstract The flooded agglomerate model has found prolific usage in modeling the oxygen reduction reaction within the cathode catalyst layer of a polymer electrolyte membrane fuel cell (PEMFC). The assumption made in this model is that the ionomer-coated carbon–platinum agglomerate is spherical in shape and that the spheres are non-overlapping. This assumption is convenient because the governing equations lend themselves to closed-form analytical solution when a spherical shape is assumed. In reality, micrographs of the catalyst layer show that the agglomerates are best represented by sets of overlapping spheres of unequal radii. In this article, the flooded agglomerate is generalized by considering overlapping spheres of unequal radii. As a first cut, only two overlapping spheres are considered. The governing reaction-diffusion equations are solved numerically using the unstructured finite-volume method. The volumetric current density is extracted for various parametric variations, and tabulated. This sub-grid-scale generalized flooded agglomerate model is first validated and finally coupled to a computational fluid dynamics (CFD) code for predicting the performance of the PEMFC. Results show that when the agglomerates are small (
Linking individual medicare health claims data with work-life claims and other administrative data

Researchers investigating health outcomes for populations over age 65 can utilize Medicare claims data, but these data include no direct information about individuals’ health prior to age 65 and are not typically linkable to files containing data on exposures and behaviors during their worklives. The current paper is a proof-of-concept, of merging employers’ administrative data and private, employment-based health claims with Medicare data. Characteristics of the linked data, including sensitivity and specificity, are evaluated with an eye toward potential uses of such linked data. This paper uses a sample of former manufacturing workers from an industrial cohort as a test case. The dataset created by this integration could be useful to research in areas such as social epidemiology and occupational health. Medicare and employment administrative data were linked for a large cohort of manufacturing workers (employed at some point during 1996–2008) who transitioned onto Medicare between 2001–2009. Data on work-life health, including biometric indicators, were used to predict health at age 65 and to investigate the concordance of employment-based insurance claims with subsequent Medicare insurance claims. Chronic diseases were found to have relatively high levels of concordance between employment-based private insurance and subsequent Medicare insurance. Information about patient health prior to receipt of Medicare, including biometric indicators, were found to predict health at age 65. Combining these data allows for evaluation of continuous health trajectories, as well as modeling later-life health as a function of work-life behaviors and exposures. It also provides a potential endpoint for occupational health research. This is the first harmonization of its kind, providing a proof-of-concept. The dataset created by this integration could be useful for research in areas such as social epidemiology and occupational health.
Small hospitals with positive cash flow: why are they winners?

This study evaluates the cash flow performance of hospitals that are at a greater risk of closure, specifically small hospitals. Sampling the majority of small acute-care hospitals in the United States, the study evaluates urban and rural small hospitals with positive cash flows for four consecutive fiscal periods and compares them with urban and rural hospitals with consecutive negative cash flows. In both urban and rural settings, positive cash flow small hospitals operate under a not-for-profit form of ownership and have lower operating costs, a faster collection of receivables. They also own newer, larger facilities, possess a Medicare higher case mix index, and offer more services in markets with lower per capita income.
Score tests in a generalized linear model with surrogate covariates

We consider generalized linear models where a predictor is measured with error. The efficient score test for the effect of that predictor depends on the regression of the true predictor on its observed surrogate. Using validation data, we estimate the regression by nonparametric techniques. The resulting semiparametric score test is shown to be nearly asymptotically efficient.
Substrate Deformation Predicts Neuronal Growth Cone Advance

Although pulling forces have been observed in axonal growth for several decades, their underlying mechanisms, absolute magnitudes, and exact roles are not well understood. In this study, using two different experimental approaches, we quantified retrograde traction force in Aplysia californica neuronal growth cones as they develop over time in response to a new adhesion substrate. In the first approach, we developed a novel method, to our knowledge, for measuring traction forces using an atomic force microscope (AFM) with a cantilever that was modified with an Aplysia cell adhesion molecule (apCAM)-coated microbead. In the second approach, we used force-calibrated glass microneedles coated with apCAM ligands to guide growth cone advance. The traction force exerted by the growth cone was measured by monitoring the microneedle deflection using an optical microscope. Both approaches showed that Aplysia growth cones can develop traction forces in the 10(0)-10(2) nN range during adhesion-mediated advance. Moreover, our results suggest that the level of traction force is directly correlated to the stiffness of the microneedle, which is consistent with a reinforcement mechanism previously observed in other cell types. Interestingly, the absolute level of traction force did not correlate with growth cone advance toward the adhesion site, but the amount of microneedle deflection did. In cases of adhesion-mediated growth cone advance, the mean needle deflection was 1.05 ± 0.07 μm. By contrast, the mean deflection was significantly lower (0.48 ± 0.06 μm) when the growth cones did not advance. Our data support a hypothesis that adhesion complexes, which can undergo micron-scale elastic deformation, regulate the coupling between the retrogradely flowing actin cytoskeleton and apCAM substrates, stimulating growth cone advance if sufficiently abundant.
Fast decentralized gradient descent method and applications to in-situ seismic tomography

We consider the decentralized consensus optimization problem arising from in-situ seismic tomography in large-scale sensor networks. Unlike traditional seismic imaging performed in a centralized location, each node in this setting privately holds an objective function and partial data. The goal of each node is to obtain the optimal solution of the whole seismic image, while communicating only with its immediate neighbors. We present a fast decentralized gradient descent method and prove that this new method can reach optimal convergence rate of O(1/k2) where k is the number of communication/iteration rounds. Extensive numerical experiments on synthetic and real-world sensor network seismic data demonstrate that the proposed algorithms significantly outperform existing methods.
Does The Mix Of A State‟s Tax Portfolio Matter? An Empirical Analysis Of United States Tax Portfolios And The Relationship To Levels And Growth In Real Per Capita Gross State Product

An important part of the economic environment for any business is the tax climate. At the federal level, arguments are often made for abandoning the income tax in favor of a national sales tax or other type of tax. At the state level, the United States has a laboratory of sorts for examining the economic impact of various types of taxes. The states exhibit a wide degree of variation in the kinds and mix of taxes upon which they rely to raise revenue. This provides an opportunity for comparing economic well-being with the mix of taxes for the various states. This paper presents the results of an empirical study of the relationship between the relative economic well-being of a state and its relative portfolio of taxation. Data on the kinds and relative mix of taxes for the 50 United States for the years 1993-1999 are summarized. While the direction of causation is still an issue, the results of the study show that statistically significant relationships do exist between a state’s tax portfolio and its level and growth of real per capita gross state product. Hopefully this study will add to our understanding of the impact of taxation on the economic climate for business.
Modeling Temperature Distributions in a Nuclear Fuel Rod With the Integral Technique

There is a large amount of research in the modeling of nuclear reactor fuel rods for various parameters amongst which the temperature is high on the list, reason being the critical temperature limit above which control of geometry will be lost as a meltdown or a partial meltdown may occur. Much of this research involves complex numerical models that are of little help especially to students learning the basics of nuclear engineering and heat transfer. This paper will explore the possibility of utilizing the integral technique for such modeling. The advantage of the technique is its simplicity which comes at the cost of some accuracy. An example is given here for a simplified cross-sectional geometry to illustrate how this modeling is done, and why it may be a superior technique to at least introduce students to the concept, but which may have applications to research in the field as well.© 2013 ASME
Neurodevelopmental Outcome of Opsoclonus-Ataxia

Cognitive, adaptive behavior, academic, speech and language, and motor abilities were assessed in 19 children with opsoclonus-ataxia and neuroblastoma, followed at University of Southern California, Los Angeles, CA.
Pharmacology Review: Caffeine Use in Neonates: Indications, Pharmacokinetics, Clinical Effects, Outcomes

Caffeine is commonly prescribed in the NICU to treat apnea of prematurity. This review is an update based on current knowledge of the mechanisms of action, pharmacologic properties, clinical effects, and safety of caffeine in the neonatal population. Recent studies of caffeine in the neonatal population confirm its efficacy in treating apnea-related symptoms and reveal additional significant benefits with minimal short-term, and no long-term, adverse effects.
Never routine: diagnostic imaging should be individualized and based on professional judgment.

Diagnostic imaging often is important in the interpretation and management of craniofacial pain, temporomandibular joint dysfunction, and sleep disorders – topics central in interest to readers of ...
Thinking about "Earth Hour" Activity and the Relation with Power Network Operation

"Earth Hour" is an activity to enhance citizens' realization for energy saving,but it may cause somewhat impacts on power network.In this paper the motive,objectives and development of "Earth Hour" are introduced.Then,based on the actual situation of power networks in China,effects and practical significance of this activity are analyzed objectively from the aspects of energy saving,generator unit characteristics and safety operation of power network etc.Finally,suggestions on how to take part in "Earth Hour" activity,how to act in daily life and how to develop our power network are proposed.
Adaptation of Respiratory Muscles to Acute and Chronic Stress: Considerations on Energy and Fuels

Although the majority of patients with acute or chronic pulmonary disease and respiratory failure do not have respiratory muscle disease or dysfunction at the outset of their clinical condition, most if not all do not have a normal respiratory musculature at the time of respiratory failure, especially those who have had a chronic course. Indeed, a large number of alterations in the muscle structure and metabolism occur as a result of a chronic load. Most of these changes are compensatory, but some may be maladaptive and deleterious to function. In addition, the compensatory mechanisms can be limited, and it is now believed that respiratory failure is at least in part exaggerated, or initiated, by the failure of the respiratory musculature. Therefore, the failure of these muscles can lead to hypoventilation, apnea, poor gas exchange, and clinically serious cardiovascular consequences. Although research efforts have increased in the past several years, there is still a great deal to learn about the function of the respiratory musculature under stress. Some of the notable questions are: What is the relation between inspiratory muscles (for example, the diaphragm and the intercostals) and the muscles of the airways during loaded breathing and in the presence of respiratory failure? How does the differential respiratory output to the various motor neuron pools change and evolve during the chronic loaded breathing? What kind of compensatory mechanisms (for example, humoral, biochemical, neural, or mechanical) can the respiratory muscles use to preserve function? What is the relation between the nutritional status of the individual and its effect on the function of these muscles? and What effect(s) do the changes associated with chronic pulmonary disease (for example, hypoxia, hypercapnea) have on respiratory muscle metabolism and function? This is an exciting area of research that has enormous potential for clinical applicability, and we believe that we are just at the very beginning.
The surgical anatomy of the heart in tubular hypoplasia of the transverse aorta (preductal coarctation)

Two hundred nineteen hearts with preductal coarctation (tubular hypoplasia) were analyzed in the laboratory to aid in surgical correction. One hundred fourteen were without and 105 were with ventricular septal defect We believe the following anatomic findings may be responsible for the mortality and morbidity in surgical repair. (1) The smallness and thinness of the left atrium (40 % in those hearts without and 24% in those with ventricular septal defect); (2) the smallness and thinness of the left ventricle (46% in those without and 32 % in those with ventricular septal defect); (3) the presence of mitral stenosis (35 % in those without and 24 % in those with ventricular septal defect); (4) the presence of unicuspid or bicuspid dysplastic aortic valve (49% in those without and 50% in those with ventricular septal defect); (5) the presence of a combination of aortic and mitral stenosis (22% in those without and 9% in those with ventricular septal defect); (6) the location of the ventricular septal defect when present; and (7) the possibility of stenosis or insufficiency of the dysplastic aortic valve in the late postoperative period.