cssi/SciSciGPT-SciSciNet huggingface dataset:
Atomistic simulation of the formation and fracture of oxide bifilms in cast aluminum

Abstract The formation and entrainment of double layer oxides (bifilms) in aluminum casting is inevitable due to the high oxidation rate of liquid aluminum and particularly turbulence during the mold filling process. The final mechanical properties of the aluminum castings suffer from these inclusions but neither the formation process nor fracture mechanism is fully understood due to the difficulty of in-situ observation on nano-scale aluminum oxide thin film. To understand the impact of bifilms on the fracture mechanism at different bifilm formation stages and the aging processes, atomic level bifilm slab models were built according to their formation history. ReaxFF reactive forcefield-based molecular dynamics (MD) method was used to simulate the formation and deformation of different types of bifilms. The MD simulations showed that an incomplete “healing” process happened at the oxide/oxide interface during bifilm formation and the fracture occurred at the Al/oxide interface instead of the oxide/oxide interface. When the oxide transformed from amorphous to α-Al2O3 due to aging, the fracture energy increased from 0.43 J/m2 to 0.53 J/m2. With 30% coverage of hydroxyl group surface contamination, the –OH terminated oxide bifilm fractured at the oxide/oxide interface and the corresponding fracture energy dropped to 0.30 J/m2. This is most likely due to the H2 bubbles being trapped in the aluminum oxide bifilm interface. To facilitate multiscale modeling, such as casting process simulation and component durability analysis, the MD predicted oxide bifilms fracture energy and fracture strength were converted to cohesive zone parameters, via a simple size bridging relationship.
Evaluation of adding the CANTAB computerized neuropsychological assessment battery to a traditional battery in a tertiary care center for veterans

Numerous advantages of and concerns about computerized neuropsychological assessment systems have been noted. Here we report a program evaluation of incorporating a computerized system, the Cambrid...
Tunable integrase-mediated differentiation facilitates improved output of burdensome functions in E. coli

Application of synthetic biology is limited by the capacity of cells to faithfully execute burdensome engineered functions in the face of Darwinian evolution. Division of labor, both metabolic and reproductive, are underutilized in confronting this barrier. To address this, we developed a serine-integrase based differentiation circuit that allows control of the population composition through tuning of the differentiation rate and number of cell divisions differentiated cells can undergo. We applied this system to T7 RNAP-driven expression of a fluorescent protein, and demonstrate both increased duration of circuit function and total production for high burden expression. While T7 expression systems are typically used for high-level short-term expression, this system enables longer duration production, and could be readily applied to burdensome or toxic products not readily produced in bacteria.
The aetiology of acute hepatitis in Taiwan: acute hepatitis superimposed on HBsAg carrier state as the main aetiology of acute hepatitis in areas with high HBsAg carrier rate.

The aetiology of sporadic acute hepatitis in Taiwan was studied in a consecutive series of 273 patients, 209 males and 64 females, aged from <1 to 73 years. Only eight patients (2.9%) had acute hepatitis A, 36 (13.2%) acute hepatitis B and 57 (20.9%) had acute non-A, non-B hepatitis (NANB). The remaining 172 patients (63.0%) were HBsAg positive but anti-HBc IgM negative and were classified as acute hepatitis in chronic HBsAg carriers. Age-specific analysis revealed that acute hepatitis types A and B accounted for 35% and 47%, respectively of acute hepatitis in patients below age 10, but their prevalence decreased dramatically with increasing age and remained quite low in patients over age 40. In contrast, acute hepatitis NANB occurred predominantly in the older patients. The prevalence of acute hepatitis NANB was 11 to 15% in patients below age 40, but increased gradually with increasing age thereafter. Of the patients over age 60, 58% had acute hepatitis NANB. Acute hepatitis in chronic HBsAg carriers accounted for 59 to 76% of acute hepatitis episodes in patients over age 10 and below age 60. Sex-specific analysis revealed that the prevalence of acute hepatitis A or B showed no significant sex difference, whereas acute hepatitis in chronic HBsAg carriers occurred predominantly in males and acute hepatitis NANB occurred predominantly in females. Of the acute hepatitis episodes in chronic HBsAg carriers about one-third was due to hepatitis Delta virus superinfection, while the remaining two-thirds were most likely acute exacerbations of the underlying hepatitis B virus infection and a few were due to non-A, non-B hepatitis superinfection.
Toward Robust Anxiety Biomarkers: A Machine Learning Approach in a Large-Scale Sample.

Abstract Background The field of psychiatry has long sought biomarkers that can objectively diagnose patients, predict treatment response, or identify individuals at risk of illness onset. However, reliable psychiatric biomarkers have yet to emerge. The recent application of machine learning techniques to develop neuroimaging-based biomarkers has yielded promising preliminary results. However, much of the work in this domain has not met best practice standards from the field of machine learning. This is especially true for studies of anxiety, creating uncertainty about the potential for anxiety biomarker development. Methods We applied machine learning tools to predict trait anxiety from neuroimaging measurements in humans. Using publicly available data from the Brain Genomics Superstruct Project, we compared a suite of neuroimaging-based machine learning models predicting anxiety within a discovery sample (n = 531, 307 women) via k-fold cross-validation, and we tested the final model (a stacked model incorporating region-to-region functional connectivity, amygdala seed-to-voxel connectivity, and volumetric and cortical thickness data) in a held-out, unseen test sample (n = 348, 209 women). Results Though the best model was able to predict anxiety within the discovery sample (cross-validated R2 of .06, permutation test p .05). Conclusions In this study, we did not find evidence of a generalizable anxiety biomarker. However, we encourage other researchers to investigate this topic, utilizing large samples and proper methodology, to clarify the potential of neuroimaging-based anxiety biomarkers.
The impact of childhood maltreatment on adolescent gang involvement.

Abstract Background A number of risk factors for gang involvement have been identified in the literature, such as victimization, poor parental monitoring, aggressive behavior, and affiliation with delinquent peers. However, few studies have examined the influence of maltreatment experiences during childhood on gang involvement later in adolescence. Objective This study examines how differential experiences of maltreatment might impact future gang involvement. Participants and setting We analyze self-report data and official maltreatment records on 611 youth (52% female; 76% non-white) in the US, from a larger dataset (Longitudinal Studies on Childhood Abuse and Neglect; N = 1354). Methods Multinomial logistic regression models were used to examine the influence of experiencing different types of maltreatment on gang involvement. Results Results show that childhood experiences of maltreatment (p = .005) generally and neglect (p = .013) specifically were significantly associated with an increased risk of involvement in stable gang affiliations later in adolescence. Conclusions These findings demonstrate the value of considering gang involvement as an outcome of maltreatment and tailoring best practice interventions to support maltreated youth at risk of gang involvement.
"Our Job is that Whole Gray Zone in Between There": Investigating Genetic Counselors' Strategies for Managing and Communicating Uncertainty.

Ample research suggests that uncertainty is a major concern for individuals undergoing genetic testing and for genetic mutation carriers, and that their management of uncertainty is largely influen...
Interactions between Dpr11 and DIP-γ control selection of amacrine neurons in Drosophila color vision circuits

Drosophila R7 UV photoreceptors (PRs) are divided into yellow (y) and pale (p) subtypes. yR7 PRs express the Dpr11 cell surface protein and are presynaptic to Dm8 amacrine neurons (yDm8) that express Dpr11’s binding partner DIP-γ, while pR7 PRs synapse onto DIP-γ-negative pDm8. Dpr11 and DIP-γ expression patterns define ‘yellow’ and ‘pale’ color vision circuits. We examined Dm8 neurons in these circuits by electron microscopic reconstruction and expansion microscopy. DIP-γ and dpr11 mutations affect the morphologies of yDm8 distal (‘home column’) dendrites. yDm8 neurons are generated in excess during development and compete for presynaptic yR7 PRs, and interactions between Dpr11 and DIP-γ are required for yDm8 survival. These interactions also allow yDm8 neurons to select yR7 PRs as their appropriate home column partners. yDm8 and pDm8 neurons do not normally compete for survival signals or R7 partners, but can be forced to do so by manipulation of R7 subtype fate.
Rapid Decrease in Liver Graft Steatosis in the Early Post-transplant Period: A Blinded and Randomized Study.

Abstract Aims Previous research suggests a rapid post-transplant decrease in liver steatosis. With increased use of liver grafts with steatosis, better understanding of this post-transplant change will facilitate successful liver transplantation. This study compares liver reperfusion biopsies with early post-transplant surveillance biopsies to evaluate and quantitate change in steatosis. Methods All liver grafts with ≥ 10% steatosis were extracted for analysis. Allograft biopsies on day 0 and day 3 post-transplant were randomly read, in a blinded fashion, by a single, experienced liver pathologist. Ten non-steatotic grafts were interspersed as controls. Slides were scored for macro-, micro-, and total steatosis. Results Overall, 151 subjects with steatosis were available for study. A decrease in steatosis was seen for most grafts: microvesicular (69%), macrovesicular (64%), and total steatosis (77%). There was a greater decrease in steatosis for grafts with high baseline steatosis (> 40% baseline steatosis with -30% reduction; 20%-39% baseline steatosis with -15% reduction; and Conclusions These results confirm a marked post-transplant decrease in steatosis that occurs within 3 to 5 days for most liver grafts with steatosis. These findings support the continued use of liver grafts with steatosis as this pathology appears to resolve quickly after transplant.
Measuring serum estradiol and progesterone one day prior to frozen embryo transfer improves live birth rates

Given no consensus in the literature, this study sought to determine if a protocol of measuring serum estradiol and progesterone the day prior to frozen embryo transfer (FET) improves likelihood of pregnancy and livebirth. This was a retrospective time-series study of women undergoing autologous vitrified-warmed blastocyst programmed FETs at an academic institution. Live birth rates were compared between a surveillance protocol, where serum estrogen and progesterone surveillance are performed the day prior to a programmed FET, and a standard protocol, whereby no hormonal lab evaluation is performed the day prior. Three hundred seventy-nine standard FET and 524 surveillance FET cycles were performed. Patients in the surveillance protocol were significantly more likely to achieve live birth (51% vs. 39%; aOR 1.6, 95%CI [1.2, 2.2]). Obese women were noted to be more likely to have lower progesterone hormone levels on surveillance labs (OR 3.2, 95%CI [2.0, 5.3]). However those whose hormonal medication dose was modified because of pre-transfer labs were as likely to achieve live birth as those whose dose was not modified (47% vs. 53%; aOR 0.8, 95%CI [0.6, 1.2]). Cycles with the surveillance protocol were more likely to result in live birth. Patients with low levels of pre-transfer hormones, such as obese patients, likely have lower pregnancy rates. It is possible that when these levels were corrected after measurement, pregnancy rates improved to match those whose levels were not low enough to warrant intervention.
Comprehensive Endogenous Tagging of Basement Membrane Components Reveals Dynamic Movement within the Matrix Scaffolding

Summary Basement membranes (BMs) are supramolecular matrices built on laminin and type IV collagen networks that provide structural and signaling support to tissues. BM complexity, however, has hindered an understanding of its formation, dynamics, and regulation. Using genome editing, we tagged 29 BM matrix components and receptors in C. elegans with mNeonGreen. Here, we report a common template that initiates BM formation, which rapidly diversifies during tissue differentiation. Through photobleaching studies, we show that BMs are not static—surprisingly, many matrix proteins move within the laminin and collagen scaffoldings. Finally, quantitative imaging, conditional knockdown, and optical highlighting indicate that papilin, a poorly studied glycoprotein, is the most abundant component in the gonadal BM, where it facilitates type IV collagen removal during BM expansion and tissue growth. Together, this work introduces methods for holistic investigation of BM regulation and reveals that BMs are highly dynamic and capable of rapid change to support tissues.
Developing interagency collaboration to address the opioid epidemic: A scoping review of joint criminal justice and healthcare initiatives

Abstract Background With the current opioid epidemic impacting well over half of all counties across the United States, initiatives that encourage interagency collaboration between first responder organizations appear necessary to comprehensively address this crisis. Police, fire, and emergency medical services (EMS) are in a unique position to identify substance users and provide necessary resources to initiate treatment, yet there is not sufficient evidence of joint collaborative programs between law enforcement/first responders and healthcare providers. Methods In this scoping review we examine the current state of joint criminal justice and healthcare interventions, specifically, opioid and substance use pre-arrest initiatives via emergency first responders and police officers. We relied on data from the last 10 years across three major databases to assess the extent of criminal justice (CJ) and healthcare collaborations as a response to individuals with opioid use disorder (OUD). We specifically focused on interventional programs between criminal justice first responders (pre-arrest) and healthcare providers where specific outcomes were documented. Results We identified only a small number (6) of studies involving interventions that met this criteria, suggesting very limited study of joint interagency collaboration between law enforcement first responders and healthcare providers. Most had small samples, none were in the southern states, and all but one were initiated within the last 5 years. Conclusions Although studies describing joint efforts of early intercept criminal justice responses and healthcare interventions were few, existing studies suggest that such programs were effective at improving treatment referral and retention outcomes. Greater resources are needed to encourage criminal justice and healthcare collaboration and policies, making it easier to share data, refer patients, and coordinate care for individuals with OUD.
Thickness and Competition in Ride-Sharing Markets

We study the effects of thickness and competition on the equilibria of ride-sharing markets, in which price-setting firms provide platforms to match customers ("riders'') and workers ("drivers''). To study thickness, we vary the number of potential workers ("the labor pool'') and, to study competition, we change the number of firms from one to two. When the market is sufficiently thick, wage and workers' average welfare decrease with size of the labor pool. Otherwise, wage and workers' average welfare increase with the labor pool, reversing the prediction by the law of demand. Intuitively, workers are "complements'' in a thin market - their wage and average welfare goes up with the labor pool - but they become "substitutes" and compete with each other in a thick market. We demonstrate that a similar insight holds in another context: consider improving the matching technology, i.e. improving the matching algorithm of the firm so that service quality goes up, given the same labor supply. We show that improving the matching technology can be like increasing the labor pool, benefiting workers when the market is not sufficiently thick, while otherwise reducing their wage and average welfare. In other words, matching technology complements labor in a thin market, but substitutes it in a thick market. We study competition by comparing the monopoly and duopoly equilibria. We find that competition benefits workers: their wage and average welfare are always higher in the duopoly equilibrium. However, the effect of competition on price and customers' average welfare depends on thickness. When the market is not sufficiently thick, there is an adverse effect of competition on customers: price is higher and customers' average welfare is lower in the duopoly equilibrium.
Filmless quality assurance of a Leksell Gamma Knife® Icon™.

Purpose The annual quality assurance (QA) of Leksell Gamma Knife® (LGK) systems are typically performed using films. Film is a good candidate for small field dosimetry due to its high spatial resolution and availability. However, there are multiple challenges with using film; film does not provide real-time measurement and requires batch-specific calibration. Our findings show that active detector-based QA can simplify the procedure and save time without loss of accuracy. Methods Annual QA tests for a LGK Icon™ system were performed using both film-based and filmless techniques. Output calibration, relative output factors (ROF), radiation profiles, sector uniformity/source counting, and verification of the unit center point (UCP) and radiation focal point (RFP) coincidence tests were performed. Radiochromic films, two ionization chambers, and a synthetic diamond detector were used for the measurements. Results were compared and verified with the treatment planning system (TPS). Results The measured dose rate of the LGK Icon was within 0.4% of the TPS value set at the time of commissioning using an ionization chamber. ROF for the 8 and 4-mm collimators were found to be 0.3% and 1.8% different from TPS values using the MicroDiamond detector and 2.6% and 1.9% different for film, respectively. Excellent agreement was found between TPS and measured dose profiles using the MicroDiamond detector which was within 1%/1 mm vs 2%/1 mm for film. Sector uniformity was found to be within 1% for all eight sectors measured using an ionization chamber. Verification of UCP and RFP coincidence using the MicroDiamond detector and pinprick film test was within 0.3 mm at isocenter for both. Conclusion The annual QA of a LGK Icon was successfully performed by employing filmless techniques. Comparable results were obtained using radiochromic films. Utilizing active detectors instead of films simplifies the QA process and saves time without loss of accuracy.
On the basis of sex: Differences in safety discrimination vs. conditioned inhibition

Inaccurate discrimination between threat and safety cues is a common symptom of anxiety disorders such as Post-Traumatic Stress Disorder (PTSD). Although females experience higher rates of these disorders than males, the body of literature examining sex differences in safety learning is still growing. Learning to discriminate safety cues from threat cues requires downregulating fear to the safety cue while continuing to express fear to the threat cue. However, successful discrimination between safety and threat cues does not necessarily guarantee that the safety cue can effectively reduce fear to the threat cue when they are presented together. The conditioned inhibitory ability of a safety cue to reduce fear in the presence of both safety and threat is most likely dependent on the ability to discriminate between the two. There are relatively few studies exploring conditioned inhibition as a method of safety learning. Adding to this knowledge gap is the general lack of inclusion of female subjects within these studies. In this review, we provide a qualitative review of our current knowledge of sex differences in safety discrimination versus conditioned inhibition in both humans and rodents. Overall, the literature suggests that while females and males perform similarly in discrimination learning, females show deficits in conditioned inhibition compared to males. Furthermore, while estrogen appears to have a protective effect on safety learning in humans, increased estrogen in female rodents appears to be correlated with impaired safety learning performance.
Trade and Credit on the Ground: Sebastian de Torres’ Regional Credit Networks Across the Rio de la Plata in the Early Nineteenth Century

Based on Sebastian de Torres’ accounting books and commercial correspondence this essay shows that, despite the disruptions caused by political and commercial changes taking place in the Rio de la Plata between 1790 and 1820, Spanish merchants like Torres managed to sustain and expand their commercial operations. Access to voluminous consumer markets distant from seaports was essential to keep Torres in business when the presence of foreign merchants and their imports became more noticeable in Buenos Aires, Montevideo, Valparaiso, and Arica. Although scarce and more expensive, commercial credit cemented partnerships and continued structuring domestic and international trade to the benefit of those who had access to coveted commodities for export as well as widely consumed domestically produced ones.
Beyond the Gender Binary: Transgender Labor Force Status in the United States 2014-2017

Following the recent acknowledgment of and debates around transgender people in the United States, there has emerged a small but growing literature on the economic implications of being transgender. However, this literature has either failed to account for major components of gender by only including gender identity or has been belied by sampling bias, both of which may entail drastic mischaracterizations of transgender labor market outcomes. This paper builds from social identity theory to provide a formal model of gender - the interplay between gender identity, expression, and perception. We apply this model using the Behavioral Risk Factors Surveillance Systems 2014-2017 and find evidence of labor market penalties associated with feminine identities, expressions, and perceptions.
Colossal thermo-hydro-electrochemical voltage generation for self-sustainable operation of electronics.

Thermoelectrics are suited to converting dissipated heat into electricity for operating electronics, but the small voltage (~0.1 mV K−1) from the Seebeck effect has been one of the major hurdles in practical implementation. Here an approach with thermo-hydro-electrochemical effects can generate a large thermal-to-electrical energy conversion factor (TtoE factor), −87 mV K−1 with low-cost carbon steel electrodes and a solid-state polyelectrolyte made of polyaniline and polystyrene sulfonate (PANI:PSS). We discovered that the thermo-diffusion of water in PANI:PSS under a temperature gradient induced less (or more) water on the hotter (or colder) side, raising (or lowering) the corrosion overpotential in the hotter (or colder) side and thereby generating output power between the electrodes. Our findings are expected to facilitate subsequent research for further increasing the TtoE factor and utilizing dissipated thermal energy. Thermoelectrics are suited to converting dissipated heat into electricity for operating electronics but limited by the small voltage from the Seebeck effect. Here, the authors report a thermo-hydro-electrochemical hybrid device with −87 mV K−1.
ALUMINUM SHEET BUMPERS

Aluminum alloy 7029 anodized sheet bumpers are being adopted by the automobile manufacturers because they are the most weight efficient and the easiest to form of all aluminum bumpers. The relative weight of aluminum bumpers is given along with additional information on aluminum sheet bumpers. Such topics as alloy selection, design considerations, corrosion, forming and finishing are discussed.
Chapter 30 Functional integrity of neural systems related to memory in Alzheimer's disease

Publisher Summary This chapter examines the functional status of the neural systems that subserve memory in the human brain suffering from Alzheimer's disease (AD). Anatomical evidence suggests loss of projection neurons and widespread disconnection of the hippocampal formation and association cortices in AD. This is perhaps most pronounced in the perforant pathway, the projection from the entorhinal cortex to the dentate gyrus that is uniformly destroyed in AD. The new methodologies can examine the functional integrity of hippocampal projections in the postmortem human brain, and through which it is found that there is impairment of the neural elements that are directly affected by the disease process (that is, by neurofibrillary tangles) as well as downstream of the pathological changes. These results highlight the effect of the disease process in disrupting neural systems, thereby causing the impairment of memory function that is so prominent in patients with AD.
EXPRESSION OF CLONED BOVINE ADRENAL RHODANESE

A cDNA for the enzyme rhodanese (thiosulfate:cyanide sulfurtransferase, EC 2.8.1.1) has been cloned from a bovine adrenal library. An initiator methionine codon precedes the amino-terminal amino acid found in the isolated protein. Rhodanese is synthesized in the cytoplasm and transferred to the mitochondrial matrix. Thus, any amino-terminal sequence required for organelle import is retained in the mature protein. Furthermore, the DNA sequence shows that there are three additional amino acids, Gly-Lys-Ala, at the carboxyl terminus that are not found by protein sequencing. Additionally, comparison of the published amino acid sequence with that encoded by the open reading frame revealed three differences in the amino acid sequence. Comparison of the bovine and chicken liver sequences shows an overall level of 70% sequence homology, but there is complete identity of all residues that have been implicated in the function of the enzyme. When two mammalian cells, cos-7 and 293 cells, were transiently transfected with a plasmid containing the rhodanese coding region, rhodanese activity in lysates increased approximately 20-fold. Fluorograms of denaturing polyacrylamide gels detected a large increase in a polypeptide that co-migrated with the native protein and reacted with anti-rhodanese antibodies. Nondenaturing gels showed two active species that co-migrated with the two major electrophoretic forms purified by current procedures. Escherichia coli, transformed with a plasmid containing the rhodanese coding region, showed a 15-fold increase in rhodanese activity over baseline values. When the E. coli recombinant protein was analyzed on a nondenaturing gel, only one species was observed that co-electrophoresed with the more electropositive variant seen in purified bovine liver rhodanese. This single variant could be converted by carboxypeptidase B digestion to a form of the enzyme that co-migrated with the more electronegative species isolated from bovine liver. Thus, two major, enzymatically active electrophoretic variants, commonly observed in mammalian cells, can be accounted for by carboxyl-terminal processing without recourse to other post-translational modifications.
The even-odd systematics in R-process nuclide abundances

We report and discuss solar system N R abundances for nuclides A > 70, obtained as differences between measured solar system abundances and calculated S-process contributions. The abundance peak at A ≈ 163 in the rare Earth element region reveals properties which are similar to those of the R-process peaks corresponding to magic neutron numbers N = 82 and N = 126. We observe that systematic differences in the N R abundances of even-A and odd-A nuclides are restricted to specific mass regions. We discuss possible interpretations and conclude that these differences are most probably related to the properties of nuclear species during β− -decay to the stability valley.
Attention activates winner-take-all competition among visual filters

Shifting attention away from a visual stimulus reduces, but does not abolish, visual discrimination performance. This residual vision with 'poor' attention can be compared to normal vision with 'full' attention to reveal how attention alters visual perception. We report large differences between residual and normal visual thresholds for discriminating the orientation or spatial frequency of simple patterns, and smaller differences for discriminating contrast. A computational model, in which attention activates a winner-take-all competition among overlapping visual filters, quantitatively accounts for all observations. Our model predicts that the effects of attention on visual cortical neurons include increased contrast gain as well as sharper tuning to orientation and spatial frequency.
Patterned abusive bruises of the buttocks and the pinnae.

Patterned bruises often result from abusive injuries. The bruise pattern commonly mimics the injuring object.1 With high-velocity injuries, like whippings or slaps, an unbruised negative image of the cord or hand may be outlined by a fine rim of petechae. At the margin of an injuring object, high-velocity impact stretches capillaries sufficiently to tear them. This may occur even when the force does not crush directly impacted vessels. Greater forces rupture directly impacted vessels creating in addition a positive image bruise of the object. If severe forces are applied more slowly, the elastic limit of the capillaries at the margins will not be exceeded.
Chemosensory Perception of Predators by Larval Amphibians Depends on Water Quality

The acquisition of sensory information by animals is central to species interactions. In aquatic environments, most taxa use chemical cues to assess predation risk and other key ecological factors. A number of laboratory studies suggest that anthropogenic pollutants can disrupt chemoreception, even when at low, non-toxic concentrations, but there are few tests of whether real-world variation in water quality affects chemoreception. Here we investigate whether chemosensory perception of predators by the gray treefrog, Hyla versicolor, depends on water quality. We evaluated the anti-predator response of anuran tadpoles housed in water collected from three sites that represent strong contrasts in the concentration and types of dissolved solids: de-chlorinated tap water, water from an impaired stream, and treated wastewater effluent. Behavioral assays were conducted in laboratory aquaria. Chemical cues associated with predation were generated by feeding tadpoles to dragonfly predators held in containers, and then transferring aliquots of water from dragonfly containers to experimental aquaria. Tadpoles housed in tap water responded to predator cues with an activity reduction of 49%. Tadpoles housed in stream water and wastewater effluent responded to predator cues by reducing activity by 29% and 24% respectively. The results of factorial ANOVA support the hypothesis that the response to predator cues depended on water type. These results show that alteration of the chemical environment can mediate chemical perception of predators in aquatic ecosystems. Because most aquatic species rely on chemoreception to gather information on the location of food and predators, any impairment of sensory perception likely has important ecological consequences.
Correlation pursuit: forward stepwise variable selection for index models

Summary. A stepwise procedure, correlation pursuit (COP), is developed for variable selection under the sufficient dimension reduction framework, in which the response variable Y is influenced by the predictors through an unknown function of a few linear combinations of them. Unlike linear stepwise regression, COP does not impose a special form of relationship (such as linear) between the response variable and the predictor variables. The COP procedure selects variables that attain the maximum correlation between the transformed response and the linear combination of the variables. Various asymptotic properties of the COP procedure are established and, in particular, its variable selection performance under a diverging number of predictors and sample size is investigated. The excellent empirical performance of the COP procedure in comparison with existing methods is demonstrated by both extensive simulation studies and a real example in functional genomics.
Semiclassical probability distribution function for finite-temperature field theory

Semiclassical methods for evaluating the canonical probability distribution function rho(phi) = in field theory for systems in thermodynamic equilibrium is studied. Field configurations which dominate the semiclassical distribution function are interpretable as finite-temperature most-probable escape paths (FTMPEP's) in field space and are related to the recently discovered caloron solutions, which are known to partially dominate the semiclassical partition function Z = ..integral..Dphi rho(phi). Presented is a semiclassical path-integral approximation for the distribution function and also discuss a Hartree self-consistent field approximation.
Optimization of nonhierarchically decomposed problems

The increasing computational power available to practitioners leads to challenging applications of optimization approaches to large scale systems. To address such problems, decomposition of the original or ''all-in-one'' (AiO) problem into smaller and simpler subproblems is the approach taken by engineers. Analytical target cascading (ATC), a hierarchical decomposition and coordination approach, is extended to model and coordinate problems with nonhierarchical interactions among the subproblems. Convergence results for ATC based on Lagrangian duality theory are extended for the new approach. Under certain conditions, the optimal solution of the AiO problem can be achieved by independently solving the nonhierarchically interacting subproblems. A mathematical example with several subproblems interacting in a network is included and new applications in engineering design are highlighted.
Kinetic aspects of plasma etching of polyimide in discharges

Abstract Etching of polyimide films in CF 4 O 2 plasma discharges is investigated. Etch rates, temperature at the film surface, optical emission intensities from the gas phase, and atomic concentrations on the polymer surface obtained by X-ray photoelectron spectroscopy (XPS) have been measured as a function of gas composition for very small reactor loads. Etch rates and XPS data for small loads are reported for the first time. With minimal contribution from ion bombardment and the approximation of certain reactive radical concentrations in the gas phase and the polymer surface, it has been possible to interpret the measured rates kinetically. A rate expression proposed earlier closely correlates with the measured etch rate data, leading to the conclusion that fluorine atom addition to the aromatic carbons in the polymer, which is known to be critical in determining the polymer radical concentration, is not the rate controlling step.
Variation in hospital admissions among small areas. A comparison of Maine and Michigan.

Analysis of age-adjusted hospital admission profiles among small geographic areas has shown marked variation in hospital admissions for both surgical and medical cases in areas ranging from Maine to Manitoba. Much of the work has been led by John Wennberg and has focused on rural areas. This study e
Microfabricated surface plasmon sensing system

Abstract The microfabricated surface plasmon sensor is a hybrid system that integrates optical, mechanical and electronic components. The sensor contains elements that are common to numerous electro-optical systems, creating a miniature optical bench. The microsystem elements include a single-mode optical fiber, a graded index collimating lens, a scanning rotating micro-mirror, a cavity filled with index matching fluid, and a position sensitive photodiode. The elements are both laterally and vertically aligned using multi-substrate bonding and positive component-to-component alignment.
White lines and d-electron occupancies for the 3d and 4d transition metals

We used electron-energy-loss spectrometry to measure the intensities of the white lines found at the onsets of the L2 and L3 absorption edges for most of the 3d and 4d transition metals. The intensities of the white lines, normalized to the trailing background, decreased nearly linearly with increasing atomic number, reflecting the filling of the d states. One-electron Hartree-Slater calculations of the white-line intensities were in good agreement with observed spectra. Empirical correlations between normalized white-line intensity and d-state occupancy provide a method for measuring changes in d-state occupancy due to alloying.
Theoretical studies of sonoluminescence radiation: Radiative transfer and parametric dependence.

We present results for sonoluminescent (SL) radiation from a strongly modulated air bubble in water. The SL pulse is due to high temperatures in the bubble that are produced by the collapse of a shock wave. The dependence of SL radiation on acoustic pressure and initial bubble size is discussed, as well as the inclusion of various mechanical energy loss mechanisms. We find that the inclusion of loss terms, especially due to radiation, is necessary in order to understand the bubble dynamics, the resulting SL pulse, and some recent experiments.
Generation and characterization of a conditional deletion allele for Lmna in mice

Extensive efforts have been devoted to study A-type lamins because mutations in their gene, LMNA in humans, are associated with a number of diseases. The mouse germline mutations in the A-type lamins (encoded by Lmna) exhibit postnatal lethality at either 4-8 postnatal (P) weeks or P16-18 days, depending on the deletion alleles. These mice exhibit defects in several tissues including hearts and skeletal muscles. Despite numerous studies, how the germline mutation of Lmna, which is expressed in many postnatal tissues, affects only selected tissues remains poorly understood. Addressing the tissue specific functions of Lmna requires the generation and careful characterization of conditional Lmna null alleles. Here we report the creation of a conditional Lmna knockout allele in mice by introducing loxP sites flanking the second exon of Lmna. The Lmna(flox/flox) mice are phenotypically normal and fertile. We show that Lmna homozygous mutants (Lmna(Δ/Δ)) generated by germline Cre expression display postnatal lethality at P16-18 days with defects similar to a recently reported germline Lmna knockout mouse that exhibits the earliest lethality compared to other germline knockout alleles. This conditional knockout mouse strain should serve as an important genetic tool to study the tissue specific roles of Lmna, which would contribute toward the understanding of various human diseases associated with A-type lamins.
Molecular model for intrinsic time-dependent dielectric breakdown in SiO2 dielectrics and the reliability implications for hyper-thin gate oxide

SiO2 films, at constant electric field, show a significant reduction in time-dependent dielectric breakdown (TDDB) performance when the thickness tox is scaled below 4.0 nm. This reduction in TDDB performance is coincident with and scales with the increase in direct tunnelling (DT) leakage through these hyper-thin oxide films. Assuming that the increase in DT leakage leads to more hole injection and trapping in the SiO2, the enhanced dielectric degradation rate with tox reduction can be explained on the basis of an intrinsic molecular model where hole capture serves to catalyze Si-O bond breakage.
Human reporter genes: potential use in clinical studies

The clinical application of positron-emission-tomography-based reporter gene imaging will expand over the next several years. The translation of reporter gene imaging technology into clinical applications is the focus of this review, with emphasis on the development and use of human reporter genes. Human reporter genes will play an increasingly more important role in this development, and it is likely that one or more reporter systems (human gene and complimentary radiopharmaceutical) will take leading roles. Three classes of human reporter genes are discussed and compared: receptors, transporters and enzymes. Examples of highly expressed cell membrane receptors include specific membrane somatostatin receptors (hSSTrs). The transporter group includes the sodium iodide symporter (hNIS) and the norepinephrine transporter (hNET). The endogenous enzyme classification includes human mitochondrial thymidine kinase 2 (hTK2). In addition, we also discuss the nonhuman dopamine 2 receptor and two viral reporter genes, the wild-type herpes simplex virus 1 thymidine kinase (HSV1-tk) gene and the HSV1-tk mutant (HSV1-sr39tk). Initial applications of reporter gene imaging in patients will be developed within two different clinical disciplines: (a) gene therapy and (b) adoptive cell-based therapies. These studies will benefit from the availability of efficient human reporter systems that can provide critical monitoring information for adenoviral-based, retroviral-based and lenteviral-based gene therapies, oncolytic bacterial and viral therapies, and adoptive cell-based therapies. Translational applications of noninvasive in vivo reporter gene imaging are likely to include: (a) quantitative monitoring of gene therapy vectors for targeting and transduction efficacy in clinical protocols by imaging the location, extent and duration of transgene expression; (b) monitoring of cell trafficking, targeting, replication and activation in adoptive T-cell and stem/progenitor cell therapies; (c) and assessments of endogenous molecular events using different inducible reporter gene imaging systems.
Protein microarray analysis of nasal polyps from aspirin-sensitive and aspirin-tolerant patients with chronic rhinosinusitis.

BACKGROUND The purpose of this study was to apply protein microarray technology to the study of sinonasal tissue and to identify differential protein expression in nasal polyps from aspirin-sensitive (AS) versus aspirin-tolerant (AT) patients with chronic rhinosinusitis (CRS) and CRS with nasal polyps (CRSwNPs). METHODS Nasal polyp specimens were prospectively obtained from two groups of patients with CRSwNP. The test group (AS) consisted of five patients that were diagnosed with CRSwNP and intolerance to aspirin based on medical history and physical exam. The control group (AT) consisted of four AT patients with CRSwNP. Protein was extracted and labeled from harvested polyps and the Sigma Panorama Antibody Microarray-Cell Signaling Kit was used to identify differences in protein expression between the two polyp groups. Western blot analysis was used to validate the results of the protein microarray. RESULTS The protein microarray showed a greater than twofold change in expression of both beta-adaptin and heat shock protein 70 (HSP70). Western blot analysis confirmed up-regulation of beta-adaptin and HSP70 in nasal polyp tissue from AS patients. CONCLUSION Pooled samples of AS and AT nasal polyps evaluated by protein microarray show distinct protein expression profiles in the stress response and receptor-mediated endocytosis pathways. This study establishes the successful application of protein microarray technology to study nasal polyposis, which in turn can be validated by Western blot analysis.
The development of the fruits and seeds of campomanesia (Myrtaceae)

The glandular nature of the “seed coat” has long been the most important taxonomic character defining the genusCampomanesia. It is shown here that the structure, which has been taken for the “seed coat,” is actually the locular wall. The development of the ovaries and seeds ofCampomanesia is discussed and illustrated. Three characteristics ofCampomanesia are identified as distinguishing it from other genera of the Myrtaceae: (1) the abortion of all but one ovule in each fertile locule; (2) the protective, glandular locular wall that serves as a false seed coat; and (3) the large number of locules in the ovaries. Reasoning is presented to explain the possible sequence of evolutionary origin of these three characteristics.
Management of ischemic nephropathy: dialysis-free survival after surgical repair.

Abstract Purpose: This retrospective review describes the surgical management of consecutive patients with severe hypertension and ischemic nephropathy due to atherosclerotic renovascular disease. Methods: From January 1987 through December 1998, a total of 590 patients underwent operative renal artery repair at our center. A subgroup of 232 hypertensive patients (97 women, 135 men; mean age, 66 ± 8 years) with atherosclerotic renovascular disease and preoperative serum creatinine levels of 1.8 mg/dL or more forms the basis of this report. Change in renal function was determined from glomerular filtration rates estimated from preoperative and postoperative serum creatinine. The influence of selected preoperative parameters and renal function response on time to dialysis and dialysis-free survival was determined by a proportional hazards regression model. Results: In all, 83 patients underwent unilateral renal artery repair and 149 patients underwent bilateral repair, including repair to a solitary kidney in 17 cases. A total of 332 renal arteries were reconstructed, and 32 nephrectomies were performed in these patients. After surgery, there were 17 deaths (7.3%) in the hospital or within 30 days of surgery. Advanced patient age ( P =.001; hazard ratio, 1.1; 95% CI [1.1, 1.2]) and congestive heart failure ( P =.04; hazard ratio, 2.9 CI [1.0, 8.6]) demonstrated significant and independent associations with perioperative mortality. With a change of 20% or more in EGFR being considered significant, 58% of patients had improved renal function, including 27 patients removed from dialysis dependence; function was unchanged in 35% and worsened in 7%. Follow-up death from all causes or progression to dialysis dependence demonstrated a significant and independent association with early renal function response. Both patients whose function was unchanged ( P =.005; hazard ratio, 6.0; CI [2.2, 16.6]) and patients whose function was worsened ( P =.03; hazard ratio, 2.2; CI [1.1, 4.5]) remained at increased risk of death or dialysis dependence. For patients with unchanged renal function after operation, risk of death or dialysis demonstrated a significant interaction with preoperative renal function. In addition to severe preoperative renal dysfunction, diabetes mellitus demonstrated a significant and independent association with follow-up death or dialysis. Conclusion: Surgical correction of atherosclerotic renovascular disease can retrieve excretory renal function in selected hypertensive patients with ischemic nephropathy. Patients with improved renal function had a significant and independent increase in dialysis-free survival in comparison with patients whose function was unchanged and patients whose function was worsened after operation. These results add further evidence in support of a prospective, randomized trial designed to define the value of renal artery intervention in patients with ischemic nephropathy. (J Vasc Surg 2000;32:472-82.)