cssi/SciSciGPT-SciSciNet huggingface dataset:
Evolutionary modification of AGS protein contributes to formation of micromeres in sea urchins.

Evolution is proposed to result, in part, from acquisition of new developmental programs. One such example is the appearance of the micromeres in a sea urchin that form by an asymmetric cell division at the 4th embryonic cleavage and function as a major signaling center in the embryo. Micromeres are not present in other echinoderms and thus are considered as a derived feature, yet its acquisition mechanism is unknown. Here, we report that the polarity factor AGS and its associated proteins are responsible for micromere formation. Evolutionary modifications of AGS protein seem to have provided the cortical recruitment and binding of AGS to the vegetal cortex, contributing to formation of micromeres in the sea urchins. Indeed, introduction of sea urchin AGS into the sea star embryo induces asymmetric cell divisions, suggesting that the molecular evolution of AGS protein is key in the transition of echinoderms to micromere formation and the current developmental style of sea urchins not seen in other echinoderms. Micromeres in a sea urchin embryo are formed by asymetric cleavage but what molecular mechanisms regulate their formation is unclear. Here, the authors show that sea urchins modify an evolutionarily conserved AGS-dependent mechanism to induce asymmetric cell divisions in the early embryo.
Family planning science and practice lessons from the 2018 International Conference on Family Planning.

Since 2009, the International Conference on Family Planning (ICFP) has served as an opportunity for the global reproductive health community to share FP advances and practice lessons in the areas of research, programming, and advocacy. The key takeaways from all 15 tracks were grouped into six thematic areas: 1) Investing in family planning for a lifetime of returns . FP may yield different health and monetary benefits but continues to face a shortage of funding, although locally owned models provide alternative financing solutions. 2) Addressing inequities in family planning for adolescents, youth, and key populations. Marginalized populations and youth still face challenges in accessing FP. Youth-inclusive and user-centered programming show promise in addressing such challenges. 3) Reproductive justice: Abortion care, family planning, and women’s wellbeing. Unsafe abortions tend to be more common among younger, poor, uneducated and rural women. Promising evidence show that providers may effectively shift from unsafe practices of dilation and curettage to safer manual vacuum aspiration or misoprostol. 4) Couple dynamics and family planning decision-making. Couples who share everyday life decision-making are more likely to use contraceptives; couple discordance on childbearing and fertility decisions directly influence women’s decisions to covertly use FP. 5) Male involvement in FP programming. Male champions and advocates can successfully promote couple uptake of FP. Gender-transformative programming promotes gender equity and can directly impact behavior change. 6) Breakthroughs in novel contraceptives and systems improvement in family planning. User-centered contraceptive technologies and information systems present an opportunity to facilitate self-care and optimal supply chain management. ICFP 2018 highlighted research advances, implementation science wins, and critical knowledge gaps in global FP access and use. More research is needed to determine the scalability of novel technologies, more effective programming and service delivery models to ensure multisectoral knowledge translation and utilization by policymakers.
Vertical GaN-on-GaN Schottky Barrier Diodes With Multi-Floating Metal Rings

Vertical GaN Schottky barrier diodes (SBDs) with floating metal rings (FMRs) as edge termination structures have been fabricated on bulk GaN substrates. Devices with different FMR geometries were investigated including various numbers of rings and various spacings between rings. These devices have a low Ron of 1.16~1.59 mΩ·cm 2 , a turn-on voltage of 0.96~ 0.94 V, a high on-off ratio of 10 9 , a nearly ideal ideality factor of 1.03~1.09, and a Schottky barrier height of 1.11~1.18 eV at room temperature. These devices have similar forward electrical characteristics, indicating that FMRs don't degrade the device rectifying performance. The ideality factor decreased and the Schottky barrier height increased with increasing temperature from 300 K to 420 K, where the temperature dependencies of the two parameters indicate the inhomogeneity of the metal/semiconductor Schottky interface. In addition, FMRs can improve device breakdown voltages. As the number of FMRs increased from 0 to 20, the reverse breakdown voltage increased from 223 to 289 V. As the spacing between the FMRs increased from 1.5 to 3 μm, the reverse breakdown voltage increased from 233 to 290 V, respectively. These results indicate multiple FMRs with proper spacings can effectively improve breakdown performance without degrading the device forward characteristics. This work represents a useful reference for the FMR termination design for GaN power devices.
Canadian Indigenous Literature and Art

In Canadian Indigenous Literature and Art (2020), Carol A. Mullen makes visible the impacts of colonization by “unsettling the settlement” (p. xiv) through reviewing both Indigenous literature, med...
Diagnostic Trends and Prescription Patterns in Disruptive Mood Dysregulation Disorder and Bipolar Disorder.

Objective Disruptive mood dysregulation disorder (DMDD) was introduced in DSM-5 to distinguish a subset of chronically irritable youth who may be incorrectly diagnosed and/or treated for pediatric bipolar disorder (BPD). This study characterized the rate of new treatment episodes and treated prevalence of BPD and DMDD from a longitudinal electronic health record database and examined the impact of DMDD on prescription trends. Method A retrospective cohort study using 2008–2018 Optum electronic health record data was conducted. Youth aged 10 to Results There were 7,677 youths with DMDD and 6,480 youths with BPD identified. Mean age (13–15 years) and ethnicity were similar for both groups. A rise in new treatment episode rates (0.87–1.75 per 1,000 patient-years, p Conclusion Diagnosis of DMDD has had rapid uptake in clinical practice but is associated with increased antipsychotic and polypharmacy prescriptions and higher rates of comorbidity and inpatient hospitalization in youth with a DMDD diagnosis compared with a BPD diagnosis.
Effect of Mechanical Debridement and Irrigation With Hypochlorous Acid Wound Management Solution on Methicillin-resistant Staphylococcus aureus Contamination and Healing Deep Dermal Wounds in a Porcine Model.

Background Wound cleansing is an important component of wound management. Purpose This study was conducted to examine the effect of a wound management solution (WMS) containing hypochlorous acid (HOCl) on methicillin-resistant Staphylococcus aureus (MRSA) and healing when used in conjunction with debridement. Methods Nineteen (19) deep reticular dermal wounds (22 mm × 22 mm × 3 mm deep) were created on the paravertebral and thoracic areas of 3 female pigs using a specialized electrokeratome. Wounds were separated by at least 5 cm to 7 cm of unwounded skin and inoculated with MRSA. After 72 hours, all wounds were debrided with a curette and irrigated with either the WMS or sterile saline solution twice per day from day 0 to day 4. Wounds then were irrigated once a day until the completion of the study (day 11). Wound tissue specimens were taken using punch biopsy for microbiological and histological analysis on days 4, 8, and 11 post treatment. Percent of wound epithelialized, epithelial thickness (cell layers µm), white cell infiltrate (1 = absent, 2 = mild, 3 = moderate, 4 = marked, 5 = exuberant), and percent of granulation tissue formation were calculated and assessed. Microbiology and histology results were analyzed for significant differences between treatments and among assessment days using one-way analysis of variance and student t-tests. A P value ≤ .05 was considered significant. Results The WMS effected a bacterial reduction (P ≤ .05) of more than 2.74 ± 0.43 and 1.03 ± 0.22 Log CFU/g in all assessment days compared with baseline before and after debridement, respectively. Percent epithelialization was significantly different between treatments on day 8, only 78.3% and 67.8% for HOCl and saline, respectively (P ≤ .05). No significant differences between treatments were observed for epithelial thickness or granulation tissue formation. Conclusion The combination of debridement and HOCl wound irrigation can significantly reduce MRSA contamination and facilitate the healing process compared to saline irrigation. Clinical studies are needed to confirm these results.
Disuse Osteopenia

It is not widely appreciated how deleterious prolonged periods of non–weight-bearing are to skeletal integrity. Rates of decline in humans exposed to prolonged spaceflight, for example, are about 10-fold greater than those observed in postmenopausal women and are associated with a significant loss of bone strength. New data on the efficacy of muscle contraction independent of weight bearing in preventing disuse osteopenia suggest that there may not be an absolute requirement for ground reaction forces to maintain bone mass. Mechanisms for disuse osteopenia are likely to involve a number factors contributing to the integrated physiologic response, including changes in interstitial fluid pressures, input from the sympathetic nervous system, and changes in bone marrow osteoprogenitor cell populations. Exciting new data using hindlimb unloaded rodents are defining the important role of the protein sclerostin in regulating Wnt/β-catenin signaling and subsequent loss of bone during periods of disuse.
Inference on quantile residual life for length-biased survival data

Length biased data occurs when a prevalent sampling is used to recruit subjects into a study that investigates the time from an initial event to a terminal event. Such data are usually left-truncated and right-censored. While there have been accurate and efficient methods to estimate the survival function, not much work has been done regarding the estimation of the residual life time distribution or the summary parameters such as the median and quantiles of the residual life. This dissertation proposes to make two new contributions. In the ﬁrst part of the dissertation, we propose two ways to estimate the quantiles of the residual life time at ﬁxed time points accounting for the length biased and censored nature of the data. We provide the asymptotic properties of these estimators and investigate them through simulation studies. Considering that the variances of these estimators require density estimation, we suggest an alternate approach taken by Jeong and others to obtain the conﬁdence interval for the available residual function. We apply these methods to a breast cancer dataset from the National Surgical Adjuvant Breast and Bowel Project (NSABP). n the second part of the dissertation, we propose a method for testing the equality of quantile residual life times from two different populations under prevalence sampling. This test can also be inverted to construct conﬁdence intervals for the ratio or difference of two quantile residual life between two populations. We compare the performance of two methods, namely, the TPL and Huang and Qin methods via simulation. The results show that the proposed tests maintain Type I error. The test based on Huang and Qin survival estimator is more powerful than that of based on the TPL estimator. We apply our methods to test the equality of median residual life of breast cancer patients having recurrence and undergoing two different treatments. Public health signiﬁcance of this research is enormous. For a population experiencing certain disease such as cancer, it is important to estimate the quantiles of the residual life time at speciﬁc time points to assess the impact of a disease and an intervention strategy on the population. This dissertation will provide accurate and efficient methods for estimating these quantiles.
Picosecond Holographic Grating Experiments in Molecular Condensed Phases

In this article some recent results from a nonlinear approach to the application of subnanosecond laser pulses to the investigation of molecular interactions and excited state dynamics are briefly described. The method involves the optical generation of a transient holographic diffraction grating in a sample, and the observation of various time and frequency dependent phenomena via subsequent Bragg diffraction from the induced grating. The basic experiment works in the following manner.
TUDCA Attenuates High Salt-Induced Renal Injury in ETB Deficient sl/sl Rats

Endothelin (ET-1) mediates sodium excretion via the ETB receptor pathway, however the ET-1/ETA receptor pathway plays a role in salt-dependent hypertension. The mechanisms by which ET-1 leads to high salt-induced renal injury are unclear. Reports have associated endoplasmic reticulum (ER) stress with renal injury, thus we hypothesized that the loss of functional ETB receptors increases high salt-induced renal injury via activation of ER stress. ETB deficient (sl/sl) rats and transgenic controls were placed on normal (1% NaCl,NSD) or high salt (8%, HSD) diet for three weeks (n=5-7/group) with daily i.p. injections of saline or the ER stress inhibitor tauroursodeoxycholic acid (TUDCA, 400 mg/kg/day). Histological injury assessments, urinary injury biomarkers, renal immune cell infiltration, renal apoptosis by TUNEL staining, and renal ER stress gene expression by qRT-PCR were studied. In sl/sl rats, HSD slightly increased glomerulosclerosis and significantly increased urinary markers of renal injury (KIM-1:...
The Evolution of the Mammalian Y Chromosome

There is a predominant theory for the evolution of the mammalian Y chromosome. This theory hypothesizes that genes for sex determination and male-specific traits, as well as sequences for X-Y meiotic pairing, are conserved on the mammalian Y chromosome across all lineages and that all other Y chromosomal genes or sequences have been or will be lost in each mammalian lineage. There are effects of mouse Y chromosomal genes on behaviors and other traits that are not male specific. Under the predominant theory, these Y chromosomal genes could be the same as the conserved genes for sex determination or malespecific traits, or they could be genes that have been lost from the Y chromosomes of other mammalian lineages and that will eventually be lost from the Y chromosome of the rodent lineage. Recently, the evolution of the primate and rodent Y chromosomes has been studied at the DNA level. These studies are summarized and reviewed in this article. The findings of these studies are not fully consistent with the predominant theory for the evolution of the mammalian Y chromosome. Also, they imply that there are other possibilities for the phylogenetic history of Y chromosomal genes of mice with effects on behavior. These are that Y chromosomal genes with effects on mouse behaviors or other traits could be conserved genes other than those for sex determination or malespecific traits or that they could be novel genes on the Y chromosome of the rodent orMus lineage.
Transformations of the Plane

Recall the notion of a “function.” A function is a rule which assigns to each number some number. This suggests the following definition: A transformation of the plane is a rule which assigns to each vector in the plane some vector in the plane.
Strain Energy Effects in the Spinodal Decomposition of Cu-Ni(Fe) Nanolaminate Coatings

A model for spinodal decomposition must account for interface effects that include gradient and strain energy terms. The measurement of diffusion in the Cu-Ni(Fe) alloy for the special case of nanolaminate structured coatings is considered wherein the composition fluctuation is one-dimensional along . An analytic approach is taken to model the kinetics of the transformation process that provides quantification of the strain energy dependence on the composition wavelength, as well as the intrinsic diffusivities and higher-order gradient-energy coefficients. The variation of the wave amplification factor R with wavenumber is modeled first to incorporate the boundary condition for growth at infinite wavelength. These results are used next to determine the gradient energy coefficients Kμ by modeling the interdiffusion coefficient ĎB variation with wavenumber, where a unique determination of the diffusion coefficient Ď is made. The value of the strain energy component that originates from interface strains associated with the epitaxial growth between layers is then determined by assessing the variation of wavelength-dependent amplification factors. A peak value of 9.4 × 107 J·m−3 for the strain energy is computed for Cu-Ni(Fe) nanolaminate coatings with 2–4 nm composition wavelengths.
Chapter 65 - Dislocation Nucleation from Crack Tips And Brittle to Ductile Transitions in Cleavage Fracture

This chapter discusses the dislocation nucleation from crack tips and brittle to ductile transitions in cleavage fracture. The fundamental mechanism of brittle versus ductile behavior of crystalline materials has been of major scientific and technological interest in materials science. It has been generally recognized that the intrinsic brittle versus ductile behavior of a single crystal is governed by the competition between cleavage fracture by atomic decohesion and plastic deformation initiated by dislocation nucleation and motion at the crack tip. The observed abrupt brittle to ductile transition in certain intrinsic brittle crystals, depending on the temperature and the strain rate, results from the eventual dislocation initiated plastic shielding of the propagating cleavage crack. The energetics of dislocation nucleation, motion, and multiplication in the highly stressed crack tip region therefore plays the major role in understanding the brittle versus ductile behavior of crystalline materials.
Divine Proportion Shape Invariance of Diffusion Limited Cluster–Cluster Aggregates

Aggregation is a non-equilibrium process of fundamental importance for all dispersed particulate systems, and the aggregates so produced are common in nature and technology. The resulting aggregates show fractal morphology with a universal, quantifiable fractal dimension. Current quantitative explanations for the fractal aggregate structure are based on simulation models that successfully describe experimental findings and have the key feature that as aggregates form, they continue to move and eventually connect with other aggregates. If the motion between meetings is diffusive, which is very typical, the process is called diffusion limited cluster aggregation (DLCA). We have shown previously that a three-parameter description, including the fractal dimension, the scaling prefactor, and the shape of these aggregates, is both necessary and sufficient to completely describe their morphology. Here we define a new shape description and find geometric relations between the dimensions of the aggregates. Moreove...
A Characteristic Factor for the 3-Term IP Roth Theorem in $\mathbb{Z}_3^\mathbb{N}$

Let $\Omega = \bigoplus_{i=1}^\infty \mathbb{Z}_3$ and $e_i = (0, \dots, 0 , 1, 0, \dots)$ where the $1$ occurs in the $i$-th coordinate. Let $\mathscr{F}=\{ \alpha \subset \mathbb{N} : \varnothing \neq \alpha, \alpha \text{ is finite} \}$. There is a natural inclusion of $\mathscr{F}$ into $\Omega$ where $\alpha \in \mathscr{F}$ is mapped to $e_\alpha = \sum_{i \in \alpha} e_i$. We give a new proof that if $E \subset \Omega$ with $d^*(E) >0$ then there exist $\omega \in \Omega$ and $\alpha \in \mathscr{F}$ such that \[ \{ \omega, \omega+ e_\alpha, \omega + 2 e_\alpha \} \subset E.\] Our proof establishes that for the ergodic reformulation of the problem there is a characteristic factor that is a one step compact extension of the Kronecker factor.
A systematic approach to model-guided empirical search for memory hierarchy optimization

The goal of this work is a systematic approach to compiler optimization for simultaneously optimizing across multiple levels of the memory hierarchy. Our approach combines compiler models and heuristics with guided empirical search to take advantage of their complementary strengths. The models and heuristics limit the search to a small number of candidate implementations, and the empirical results provide accurate feedback information to the compiler. In previous work, we propose a compiler algorithm for deriving a set of parameterized solutions, followed by a model-guided empirical search to determine the best integer parameter values and select the best overall solution. This paper focuses on formalizing the process of deriving parameter values, which is a multi-variable optimization problem, and considers the role of AI search techniques in deriving a systematic framework for the search.
Failure to rescue in trauma: Coming to terms with the second term.

Abstract Introduction The failure to rescue (FTR) rate is the probability of death after a major complication and was defined in elective surgical cohorts. In elective surgery, the precedence rate (proportion of deaths preceded by major complications) approaches 100%, but recent studies in trauma report rates of only 20–25%. We hypothesised that use of high quality data would result precedence rates in higher than those derived from national datasets, and we further sought to characterise the nature of those deaths not preceded by major complications. Methods Prospectively collected data from 2006 to 2010 from a single level I trauma centre were used. Patients age >16 years with AIS ≥2 who survived beyond the trauma bay were included. Complications, mortality, FTR, and precedence rates were calculated. Chart abstraction was performed for registry deaths without recorded complications to verify the absence of complications and determine the cause of death, after which outcomes were re-calculated. Results A total of 8004 patients were included (median age 41 (IQR 25–75), 71% male, 82% blunt, median ISS 10 (IQR 5–18)). Using registry data the precedence rate was 55%, with 132/293 (45%) deaths occurring without antecedent major complications. On chart abstraction, 11/132 (8%) patients recorded in the registry as having no complication prior to death were found to have major complications. Complication and FTR rates after chart abstraction were statistically significantly different than those derived from registry data alone (complications 16.5% vs. 16.3, FTR 12.3 vs.13, p = 0.001), but this difference was unlikely to be clinically meaningful. Patients dying without complications predominantly (87%) had neurologic causes of demise. Conclusions Use of data with near-complete ascertainment of complications results in precedence rates much higher than those from national datasets. Patients dying without precedent complications at our centre largely succumbed to progression of neurologic injury. Attempts to use FTR to compare quality between centres should be limited to high quality data. Level of evidence Level III. Retrospective cohort study Outcomes.
The application of elastic-plastic fracture mechanics parameters in fracture safe design

Abstract The report summarizes some of the methods which are currently used for assessing the fracture toughness of materials under elastic and elastic-plastic conditions. The main parameters which are considered are (1) plane strain fracture toughness (KIc), (2) equivalent energy (KIcd), (3) contour integral (J) and (4) crack opening displacement (COD). Gross strain crack tolerance and stress concentration methods are also discussed. It is concluded that of these parameters, the contour integral and the crack opening displacement have most potential for future development. These two parameters are shown to be equivalent, however, at the present stage of development the COD concept has several advantages over the J concept. Firstly, the COD concept is able to take into account, secondary stresses, such as welding residual stresses. Because these stresses are in equilibrium, they do not appear in energy measurements to evaluate J. Secondly, the COD value is a physical measure of the crack tip conditions which includes the effect of stress state and thickness. It is, therefore, possible to measure and calculate COD levels for cracks in real structures. It is not possible to evaluate J for real structures since J methods are appropriate only to in-plane problems. This also means that partial wall (thumbnail) flaws are better characterized by the COD concept. The COD concept has been developed to a stage where it is possible to estimate the significance of flaws in welded structures provided the toughness of the material and the acting stresses or strains are known. This development is described and the method used to analyze tests on model pressure vessels with 6″ thick walls. A comparison is made with other methods, and it is concluded that although the COD analysis gives conservative estimates of the flaw size to cause failure, further work is necessary to be able to predict vessel burst conditions when failure is preceded by extensive plasticity and stable ductile tearing. A simple nomogram to determine COD levels to ensure leak before break conditions is also developed.
Motivations for prescription drug misuse among young men who have sex with men (YMSM) in Philadelphia.

Abstract Background Prescription drug misuse (i.e. opioids, tranquilizers and stimulants) has become the fastest growing area of substance abuse among young adults. Limited studies focus on prescription drug misuse among young men who have sex with men (YMSM, aged 18–29 years). Furthermore, little is known about YMSM's motivations for misuse. The purpose of this study was to explore personal motivations for prescription drug misuse among YMSM, including the possible connection between misuse and sexual behaviors. Methods As part of a larger mixed methods study of 191 YMSM recruited in Philadelphia during 2012–2013, we conducted semi-structured qualitative interviews with 25 of these participants to gather additional contextual information about their prescription drug misuse. We conducted thematic analysis of qualitative data. Results While our results corroborated previous literature on motives for misuse of prescription drugs, our data yielded some distinct motivations specific among YMSM. These motives included social/recreational motives, facilitating sex with other men (including motives such as use of opioids for less painful anal receptive sex), and psychological motives such as depression, stress management, coping with everyday hardships (opioids and tranquilizers) or feeling more energized (stimulants). Prescription drugs were commonly misused within the broader contexts of participants' polysubstance use, adding to the significance of this problem. Conclusions Our findings offer insights into YMSM's motivations for prescription drug misuse, and point to the importance of recognizing and addressing them. While substance use is likely related to various psychosocial issues impacting YMSM, it also may lead to significant health consequences. Results support the need to include prescription drugs and polysubstance use in harm reduction messages and treatment approaches aimed at substance using YMSM.
Photonic VLSI for on-chip computing architectures

In this paper, we demonstrate the feasibility of using on-chip optoelectronics within VLSI systems to address a wide range of signal distribution issues by examining the following fundamental question: how can we transmit information from one source to many destinations while minimizing propagation delay, skew, jitter, and noise in a way that is compatible with low-cost manufacturing and CMOS circuits? Example systems with such information distribution requirements include banked arrayable memories such as a DRAM or a dense imager with scanned high speed readout, or a clock distribution system. In all instances individual lines are typically connnected to thousands of gates, slowing cell access times and generating skew. We demonstrate how the use of on-chip photonics within VLSI systems can reduce delays introduced by electrical wires in system-on-a-chip interconnects, busses, caches, and control lines at distances shorter than one meter and as short as a few millimeters. We also describe and demonstrate how a simple on-chip optoelectronic system addressing these problems can be realized at low cost, with monolithic photodetectors and on-chip waveguides in a commercial CMOS process, benefiting both ultra-short and one meter link architectures. This unexplored signal distribution architecture promises high optical to electrical efficiency, low noise, and the benefits of monolithic photodetection not previously achieved in existing approaches.
Esophageal bacteria and Barrett's esophagus: a preliminary report.

The objective of this study was to investigate if esophageal bacteria are associated with Barrett's esophagus (BE). This study was comprised of a retrospective (Part 1) and a subsequent prospective (Part 2) study. In Part 1, Gram stains were performed on esophageal biopsy specimens obtained in 47 patients. Bacteria were quantitated from 0 to 4. In Part II, Gram stains and cultured bacterial counts of esophageal biopsies were obtained in 18 GERD patients (9 with BE and 9 without BE). Part 1 results were as follows. Bacteria were found in 37 of 47 esophageal biopsies. Quantitative bacterial stain scores for BE (2.5±0.2) were higher than for non-BE (1.5±0.3; P = 0.02). The quantitative bacterial stain scores correlated with increasing severity of dysplasia (r = 0.37, P = 0.028). In Part 2, bacteria were found in 8 of 18 esophageal biopsies by Gram stain (6 of 9 patients with BE vs. 2 of 9 non-BE). The distal esophageal bacterial stain scores in BE patients (1.6±0.5) were higher than in those without BE (0.4±0.3; P = 0.07). Patients on proton pump inhibitors tended to have higher bacterial stain scores (1.2±0.4) than patients who were not (0.7±0.3; P = 0.45). Bacterial colony counts were similar in patients with BE compared to those without BE. In conclusion, bacteria in esophageal biopsies were detected more often in BE than non-BE. Increasing bacterial stain scores were associated with metaplasia and increasing dysplasia. Esophageal bacteria, possibly related to stasis or gastric acid suppression therapy, may play a role in the pathogenesis of BE and dysplasia.
Research opportunities in Antarctica

R/V Nathaniel B. Palmer, the 94-m ice breaking research vessel operated by the National Science Foundation's Office of Polar Programs for the United States Antarctic Program (USAP), has completed its first year of operations. The eight cruises included the recovery of the U.S. -Russian ice camp in the Weddell Sea, biological and physical oceanographic studies, a marine geology and geophysics program, and an engineering test cruise. The ship spent a large part of the year working in ice in the western Weddell, Amundsen, and Bellingshausen seas. In the 1993–1994 austral summer and 1994 austral winter seasons, funded NSF projects will extend the range of operations into the eastern Weddell and Ross seas.
Next-generation pyrosequencing of gonad transcriptomes in the polyploid lake sturgeon (Acipenser fulvescens): the relative merits of normalization and rarefaction in gene discovery

Next-generation sequencing technologies have been applied most often to model organisms or species closely related to a model. However, these methods have the potential to be valuable in many wild organisms, including those of conservation concern. We used Roche 454 pyrosequencing to characterize gene expression in polyploid lake sturgeon (Acipenser fulvescens) gonads. Titration runs on a Roche 454 GS-FLX produced more than 47,000 sequencing reads. These reads represented 20,741 unique sequences that passed quality control (mean length = 186 bp). These were assembled into 1,831 contigs (mean contig depth = 4.1 sequences). Over 4,000 sequencing reads (~19%) were assigned gene ontologies, mostly to protein, RNA, and ion binding. A total of 877 candidate SNPs were identified from > 50 different genes. We employed an analytical approach from theoretical ecology (rarefaction) to evaluate depth of sequencing coverage relative to gene discovery. We also considered the relative merits of normalized versus native cDNA libraries when using next-generation sequencing platforms. Not surprisingly, fewer genes from the normalized libraries were rRNA subunits. Rarefaction suggests that normalization has little influence on the efficiency of gene discovery, at least when working with thousands of reads from a single tissue type. Our data indicate that titration runs on 454 sequencers can characterize thousands of expressed sequence tags which can be used to identify SNPs, gene ontologies, and levels of gene expression in species of conservation concern. We anticipate that rarefaction will be useful in evaluations of gene discovery and that next-generation sequencing technologies hold great potential for the study of other non-model organisms.
The OmniTread serpentine robot for industrial inspection and surveillance

Purpose – Describes the design, construction, and performance of the OmniTread serpentine robot. Provides a review of other designs in this new area of mobile robotics. Presents innovative and unique mechanical and control solutions.Design/methodology/approach – A theoretical analysis of key aspects of the mechanical design and their implications on the performance of the robot is presented. Extensive experimentation and testing helped optimize choices of materials for the critical components: tracks and pneumatic bellows. Performance was evaluated by an independent third party: the Southwest Research Institute.Findings – It was found that pneumatic bellows are optimal joint actuators for serpentine robots. They can provide both strength and compliance, depending on the task, at minimal volume and weight.Research limitations/implications – The described prototype is tethered to external sources of electrical and pneumatic power. A smaller and fully self‐contained version of the OmniTread is currently unde...
Using quantitative methods to improve the diagnostic workup for abdominal pain in children.

Abstract Introduction The differential diagnosis of abdominal pain in children can be challenging. We applied quantitative decision-making methods to this process and sought to determine if their use provided measurable benefit. Methods After obtaining institutional review board approval, we recorded key elements of the history, physical examination, laboratory, and imaging evaluations along with the cost and the time spent in the emergency department (ED) for children presenting with abdominal pain. Initially, data were collected (group 1, n=1366 patients) and then presented to the ED pediatricians. For subsequent patients, ED physicians received a sheet specific to that patient's age and sex reporting the most common diagnoses and the elements of the evaluation that had proven most useful (group 2, n=624 patients). We compared the difference in length of stay and costs before and after intervention, between study groups, by age groups, and separately by sex using a 2-factor analysis of variance. Results The diagnostic workup cost less in boys aged 2 to 12 years after the intervention. In boys and girls older than 12 years, the cost trended lower. Discussion This study demonstrates that ED physicians equipped with specific information were able to complete their diagnostic evaluation of children presenting with abdominal pain at a lower cost.
The role of human glutathione S-transferases (hGSTs) in the detoxification of the food-derived carcinogen metabolite N-acetoxy-PhIP, and the effect of a polymorphism in hGSTA1 on colorectal cancer risk.

Abstract Food-derived heterocyclic amines (HCAs), particularly 2-amino-1-methyl-6-phenylimidazo[4,5- b ]pyridine (PhIP), are implicated in the etiology of human colorectal cancer (CRC) via a process of N -oxidation followed by O -acetylation or O -sulfation to form electrophilic metabolites that react with DNA. Glutathione S -transferases (GSTs) detoxify activated carcinogen metabolites by catalysis of their reaction with GSH. However, among HCAs, only N -acetoxy-PhIP has been shown to be a substrate for the GSTs. By using a competitive DNA-binding assay, we confirm that hGSTA1-1 is an efficient catalyst of the detoxification of N- acetoxy-PhIP. Further, we show that hGSTs A2-2, P1-1, M1-1, T1-1 and T2-2 appear to have low activity towards N- acetoxy-PhIP, and that hGSTs A4-4, M2-2, M4-4 and Z1-1 appear to have no activity towards N -acetoxy-PhIP. A genetic polymorphism in the 5′-regulatory sequence of hGSTA1 has been shown to correlate with the relative and absolute levels of expression of GSTA1/GSTA2 in human liver. Examination of hGSTA1 allele frequency in 100 Caucasian CRC patients and 226 Caucasian controls demonstrated a significant over-representation of the homozygous hGSTA1 ∗ B genotype among cases compared to controls (24.0 and 13.7%, respectively, P =0.04). This corresponds to an odds ratio for risk of CRC of 2.0 (95% CI 1.0–3.7) when comparing homozygous hGSTA1 ∗ B individuals with all other genotypes. Thus, individuals who are homozygous hGSTA1 ∗ B , and who would be predicted to have the lowest levels of hGSTA1 expression in their livers, appear to be at risk of developing CRC, possibly as a result of inefficient hepatic detoxification of N -acetoxy-PhIP.
ICA Color Space for Pattern Recognition

This paper presents a novel independent component analysis (ICA) color space method for pattern recognition. The novelty of the ICA color space method is twofold: 1) deriving effective color image representation based on ICA, and 2) implementing efficient color image classification using the independent color image representation and an enhanced Fisher model (EFM). First, the ICA color space method assumes that each color image is defined by three independent source images, which can be derived by means of a blind source separation procedure, such as ICA. Unlike the RGB color space, where the R , G, and B component images are correlated, the new ICA color space method derives three component images C 1 , C 2 , and C 3 that are independent and hence uncorrelated. Second, the three independent color component images are concatenated to form an augmented pattern vector, whose dimensionality is reduced by principal component analysis (PCA). An EFM then derives the discriminating features of the reduced pattern vector for pattern recognition. The effectiveness of the proposed ICA color space method is demonstrated using a complex grand challenge pattern recognition problem and a large scale database. In particular, the face recognition grand challenge (FRGC) and the biometric experimentation environment (BEE) reveal that for the most challenging FRGC version 2 Experiment 4, which contains 12 776 training images, 16 028 controlled target images, and 8014 uncontrolled query images, the ICA color space method achieves the face verification rate (ROC III) of 73.69% at the false accept rate (FAR) of 0.1%, compared to the face verification rate (FVR) of 67.13% of the RGB color space (using the same EFM) and 11.86% of the FRGC baseline algorithm at the same FAR.
The crystal structure of copper(II) bromide bis(dimethylsulphoxide)

Abstract {(CH3)2SO}2CuBr2 is isomorphous with the corresponding chloride complex. It belongs to the orthorhombic space group Pnma and contains 4 formula groups per unit cell. The dimensions of the unit cell at ca. 295K are a = 8.257(2)A, b = 11.772-(2)A, c = 11. 749(2)A. The copper ion assumes an intermediate five-coordinate geometry with three bromine atoms equatorial and two oxygen atoms axial. The equatorial angles are Br(1)CuBr( 2 ) = - 146.13° and Br(2)CuBr(2) =- 110.21°, and the axial angle O(1)CuO(1) is 173.99°.. The bond lengths are CuBr(1′) = 2.451(4)A, CuBr(2) = 2.429(4)A, CuBr(2′) = 2.777(4) A and cuO = 1.962(9)A. The copper coordination geometry is largely determined by packing of the DMSO groups.
Agreement between affectively based observational and parent-report measures of temperament at infant age 6 months.

This study associated two temperament measures: The Rothbart Infant Behavior Questionnaire (IBQ) and the Goldsmith and Rothbart Laboratory Temperament Assessment Battery. Seventy-one infants were observed. Mothers completed the IBQ. Observed anger related to reported distress to limitations, whereas pleasure expressions related to reported smiling and laughter.
LOGIT: A program for dose-response analysis

Abstract We describe a FORTRAN computer program for fitting the logistic distribution function: P(x)= e α+βx 1+e α+βx Where α represents dose or time, to dose-response data. The program determines both weighted least squares and maximum likelihood estimates for the parameters α and β. It also calculates the standard errors of α and β under both estimation methods, as well as the median lethal dose (LD50) and its standard error. Dose-response curves found by both fitting methods can be plotted as well as the 95% confidence bands for these lines.
Strong lower bound on squark masses in minimal N=1 supergravity

Abstract With flavor-changing gluino couplings as recently calculated in minimal N=1 supergravity, it is shown that virtual gluino-gluino 0−+ bound states make potentially very large contributions of the wrong sign to the K0 K 0 mass matrix. For m 3 2 ⋃110 GeV, m g ⩾40 GeV , they dominatein magnitude those of the supersymmetric two-gluino box diagram. The requirement that the contribution to the CP-violating parameter ϵ dueto these states not violate experimental limits imposes a strong lower bound on m squark ≈ m 3 2 : I find m squark ⩾77 GeV. (m g /40 GeV) 1 4 ) m t /35 GeV) 1 2 [(3+|A| 2 )/7] 1 2 , where A is the standard minimal N=1 supergravity parameter.
Computer simulation of sodium fluxes in frog skin epidermis.

The operation of a seven-compartment model is described with respect to flows of Na+ within and across this system, simulating published results obtained on frog skin. The seven compartments represent: one outside and one inside solution compartment; the subcorneal space; the first reacting cell layer (1. RCL); the remaining cell compartment; the non-, or slowly exchangeable Na+ compartment; the extracellular space. Assuming reasonable volumes for the epidermal compartments and further chosing, by trial and error, appropriate rate constants, a set of seven simultaneous linear differential equations was solved by the application of the Continuous System Modeling Program (CSMP), using an IBM 1130 computer. Initial conditions for influx, backflux and net flux were taken which correspond to [Na+]0; [Na+] i =115mm. Print-out data were obtained at 0.5-min intervals for 30 min, when steady states were obtained in 13 models studied, varying certaink's thus simulating actions of chemical agents (hormones; drugs). Simulation was achieved with regard to rate of influx, backflux and net flux, steady-state time (30 min), and electrical potentials. In addition, this approach gave detailed information on Na+ pool sizes and their variations with changes ink's. These results are compared to published data on frog skin and good agreement between operation of skin epidermis and model was found.
Circular waveguides induced by two-dimensional bright steady-state photorefractive spatial screening solitons.

We report what we believe is the first experimental observation of bright-soliton-induced two-dimensional waveguides. The waveguides are induced by two-dimensional photorefractive screening solitons, and their guiding properties, i.e., whether the waveguides are single mode or multimode, are controlled by adjustment of the soliton parameters.
The activation parameters for the exchange reactions between EuEDTA− and Eu(III) and Am(III)

Abstract The activation parameters were determined for the exchange between Eu∗(III) and EuEDTA− and Am∗(III) and EuEDTA−. The values of ΔH† were 11·9 (Eu) and 10·7 (Am) kcal/mole while the corresponding ΔS† values were −6·8 and −12·2 cal/°C/mole.
Enhancement- and depletion-mode vertical-channel m.o.s. gated thyristors

A new gate structure is described for power thyristors which uses the m.o.s. field effect to control the anode breakover voltage. Experimental devices have been fabricated using a V-groove etched in (100) oriented wafers and forming the gate in these grooves. Both enhancement- and depletion-mode devices have been demonstrated.
Binding sites and vibrational frequencies for dilute carbon monoxide and nitric oxide adlayers in electrochemical versus ultrahigh-vacuum environments: the roles of double-layer solvation

Abstract In situ infrared spectra for dilute (i.e., low-coverage) carbon monoxide and nitric oxide adlayers on (111) and (100) platinum, rhodium, iridium and palladium surfaces in acidic aqueous solution are compared with vibrational spectra and other structural information for the corresponding systems in ultrahigh vacuum (UHV), with the objective of assessing the roles of the solvated double layer on the preferred binding sites and vibrational frequencies. Results are considered for eight CO and five NO adlayers, involving CO ( ν CO ) and NO ( ν NO ) stretching bands, respectively. The vibrational frequencies in the electrochemical and UHV environments are compared at equivalent surface potentials by adjusting (or extrapolating) the former data to electrode potentials equivalent to the work function ( Φ ) of the latter interfaces, presuming that the absolute potential of the standard hydrogen electrode is 4.8 V. Unlike the excellent agreement between such electrochemical and UHV-based chemisorbate frequencies, ν ( Φ ), obtained previously in this fashion for saturated CO and NO adlayers, the majority of dilute adlayer systems exhibit significant (≥20 cm −1 ) disparities in the ν ( Φ ) values. In some cases, notably for Pt(100)/CO, Pt(111)/CO, Rh(111)/CO and Pd(111)/NO, the nature and magnitude of the discrepancies indicate that the energetically preferred binding site is altered by the double-layer environment, most likely by chemisorbate–coadsorbed water interactions, along with the formation of segregated chemisorbate–water domains. The milder, yet still significant, disparities between electrochemical and UHV ν ( Φ ) values that are evident for other systems, prominently for Pd(111)/CO and Pd(100)/CO, suggest the occurrence of solvation-induced perturbations on the chemisorbate binding-site population and ‘local’ surface potentials. New electrochemical infrared data are also presented for the archetypical Pt(111)/CO system. At higher electrode potentials, bordering the onset of CO electrooxidation, the pair of low-coverage ν CO bands diagnostic of both atop and bridging coordination, reflecting the influence of water coadsorption, are replaced by a lone atop ν CO feature, the latter being similar to infrared spectra observed on clean Pt(111) in UHV. This unusual potential-dependent behavior is ascribed to the preferential electrooxidation of bridging CO.
The mating-induced release of prolactin: a unique neuroendocrine response.

I. Introduction IN THE RAT, the corpus luteum is formed on the morning of estrus in response to the surge of luteinizing hormone released on the previous day, proestrus. However, unlike other mammals whose corpora lutea secrete increasing amounts of progesterone for several days (1), the newly formed corpora lutea of the rat secrete progesterone for only 2 days after formation (2, 3). In the absence of all other input, the corpora lutea subsequently fail and progesterone secretion wanes (3). It has long been appreciated that rodent corpora lutea could be maintained by either coital stimulation (4) or injection of pituitary extracts containing prolactin (PRL) activity (5, 6). An overwhelming literature now indicates that the mating stimulus induces the release of PRL which in turn “rescues” the corpora lutea of the cycle and prolongs the ability of these structures to secrete progesterone (3, 7–11). The mating stimulus or copulomimetic stimuli applied to the uterine cervix with a glass rod or appropriately...