cssi/SciSciGPT-SciSciNet huggingface dataset:
An engineered, non-diazotrophic cyanobacterium and its application in bioelectrochemical nitrogen fixation

Summary The reduction of chemically inert nitrogen to ammonia is a critical step in the global nitrogen cycle. Microbial nitrogen fixation is a promising way to realize nitrogen reduction and ammonia production at mild conditions. Here, we report an engineered, non-diazotrophic Synechococcus elongatus PCC 7942 strain with nitrogen fixation activity that is constructed by integrating a modified nitrogenase gene cluster into the genome. The engineered S. elongatus PCC 7942 strain is employed in a bioelectrochemical nitrogen-fixation (e-BNF) system for ammonia production. Because the e-BNF system supplies adequate external electrons for the turnover of nitrogenase, the nitrogen fixation activity of the engineered S. elongatus PCC 7942 strain is significantly improved. After 48 h of reaction, the e-BNF system accumulates 173 μM of NH3, which is 21 times higher than that generated from solely photosynthesis-driven nitrogen fixation, with faradaic efficiency of 6.85%. This work may provide new insight into biological nitrogen-fixation systems and ammonium production.
RTP Pockels Cell with Nanometer-Level Position Control

MOLLER is a future experiment designed to measure parity violation in Moller scattering to extremely high precision. MOLLER will measure the right-left scattering differential cross-section parity-violating asymmetry APV , in the elastic scattering of polarized electrons off an unpolarized LH2 target to extreme ppb precision. To make this measurement, the polarized electron source, generated with a circularly polarized laser beam, must have the ability to switch quickly between right and left helicity polarization states. The polarized source must also maintain minimal right-left helicity correlated beam asymmetries, including energy changes, position changes, intensity changes, or spot-size changes. These requirements can be met with appropriate choice and design of the Pockels cell used to generate the circularly polarized light. Rubidium Titanyl Phosphate (RTP) has been used in recent years for ultra-fast Pockels cell switches due to its lack of piezo-electric resonances at frequencies up to several hundred MHz. However, crystal non-uniformity in this material leads to poorer extinction ratios than in commonly used KD*P Pockels cells when used in hald-wave configuration. It leads to voltage dependent beam steering when used in quarter-wave configuration. Here we present an innovative RTP Pockels cell design which uses electric field gradients to counteract crystal non-uniformities and control beam steering down to the nm-level. We demonstrate this RTP Pockels cell design is capable of producing precisely controlled polarized electron beam at Jefferson Laboratory, a national accelerator facility, for current experiments, including the recent PREX II measurement, as well as the future MOLLER experiment.
Small target repeatability of 68 Ga and 18 F: effects of target concentration and imaging time on SUV measurements in clinically relevant phantoms

Quantification of tumor uptake using PET imaging is important for the evaluation of therapy response. For 18F FDG PET scans, a change in uptake of 25% is commonly considered significant. For scans using novel radiopharmaceuticals, the threshold of significance is unclear. Factors including imaging time, tumor size, activity concentration, and radiopharmaceutical may affect the repeatablity of uptake metrics. This work evaluates the effect of these parameters on the repeatablity of maximum SUV (SUVmax) and mean SUV (SUVmean) in phantoms using 18F and 68Ga. An Esser PET phantom (Data Spectrum, Durham NC) was scanned on a Biograph Horizon PET/CT scanner (Siemens Medical Solutions, Malvern PA) using 18F and 68Ga. Data were acquired for 5 minutes with reconstructions between 0.5-5 minutes. The background activity mimicked clinical scans with target-to-background (T/B) ratios from 1.7-19.8. The SUVmax and SUVmean were measured for 5 slices. The mean, standard deviation, and coefficient of variation (COV) were calculated. The effects of radionuclide, imaging time, activity concentration, and target size on COV were evaluated using multivariate gamma regressions. COV for 68Ga was 40% higher and 54% higher on average than for 18F for SUVmax and SUVmean, respectively. Decreased lesion size, imaging time, and activity concentration were significantly associated with increased COV for both metrics (P < 0.001). COV was substantially reduced at high T/B for 68Ga. At the highest T/B the COV for SUVmax and SUVmean was within the typical range seen for 18F. COV is relatively high for small targets (8 mm) but is dramatically reduced with high radiotracer uptake.
I Seek Pleasures, We Avoid Pains

In four experiments, we show that goals associated with approach and avoidance needs influence persuasion and that the accessibility of distinct self-views moderates these effects. Specifically, individuals with an accessible independent self-view are more persuaded by promotion-focused information that is consistent with an approach goal. In contrast, individuals whose interdependent self-view is more accessible are more persuaded by prevention focused information that is consistent with an avoidance goal. When the persuasive appeal is compatible with self-regulatory focus, individuals demonstrate greater recall of the message content and are more discerning regarding argument strength. These findings provide convergent evidence that central processing under goal compatible conditions underlies the persuasion effects.
Alternative Autoinducer-2 Quorum-Sensing Response Circuits: Impact on Microbial Community Development

Caries and periodontal disease are biofilm-mediated diseases that remain widespread and serious health problems. The dental biofilm is a complex microbial community that can comprise up to 700 bacterial species. Recent studies have made substantial progress in defining these signaling circuits and the impact that bacterial communication has on the formation and persistence of the dental biofilm. Several distinct classes of autoinducers have been identified, including numerous structurally distinct acylhomoserine lactones (AHLs), oligopeptides, quinolones, and derivatives of tetrahydrofuran. LuxS is an enzyme in the activated methyl cycle which functions in the turnover of S-adenosylhomocysteine (SAH) and generation of S-adenosylmethionine. To determine if luxS influenced virulence properties, the expression of several genes that contribute to Aggregatibacter actinomycetemcomitans virulence was analyzed after inactivation of luxS. Real-time PCR revealed that the expression of numerous genes encoding proteins involved in iron acquisition and storage was significantly altered in the luxS mutant. Biofilm growth was restored to wild-type levels either by transforming the mutant strain with a functional copy of luxS or by the addition of partially purified AI-2 to the growth medium. To determine if AI-2 represents a true quorum-sensing signal, Rezzonico and Duffy compiled and searched a microbial genome database for known AI-2 receptors, i.e., LuxQP and LsrB, and then compared the distribution of these proteins with published studies that examined quorum-sensing phenotypes in the organisms. The widespread distribution of LuxS in both gram-negative and gram-positive bacteria has led to the suggestion that AI-2 represents a universal quorum-sensing system that mediates interspecies communication.
Hilbert-Schmidt Geometry of n-Level Jakobczyk-Siennicki Two-Dimensional Quantum Systems

Jakobczyk and Siennicki studied two-dimensional sections of a set of (generalized) Bloch vec- tors corresponding to n × n density matrices of two-qubit systems (that is, the case n = 4). They found essentially five different types of (nontrivial) separability regimes. We compute the Euclidean/Hilbert-Schmidt (HS) separability probabilities assigned to these regimes, and conduct parallel two-dimensional sectional analyses for the higher-level cases n = 6,8,9 and 10. Making use of the newly-introduced capability for integration over implicitly defined regions of version 5.1 of Mathematica — as we have also fruitfully done in the n = 4 three-parameter entropy- maximization-based study quant-ph/0507203 — we obtain a wide-ranging variety of exact HS- probabilities. For n > 6, the probabilities are those of having a partial positive transpose (PPT). For the n = 6 case, we also obtain biseparability probabilities; in the n = 8,9 instances, bi-PPT probabilities; and for n = 8, tri-PPT probabilities. By far, the most frequently recorded probabil- ity for n > 4 is � � 0.785398. We also conduct a number of related analyses, pertaining to the (one-dimensional) boundaries (both exterior and interior) of the separability and PPT domains, and attempt (with quite limited success) some exact calculations pertaining to the 9-dimensional (real) and 15-dimensional (complex) convex sets of two-qubit density matrices — for which exact HS-separability probabilities have been conjectured, but not yet verified.
On the Term Structure of Interest Rates in the Presence of Reflecting and Absorbing Boundaries

To preclude arbitrage, nominal interest rates must remain non-negative. Researchers have captured this feature by modeling the spot rate with volatility structures that vanish as the spot rate tends to zero. However, such volatility structures are in conflict with empirical evidence; volatility can remain relatively large even at low interest rates. In this paper, we investigate the term structure of interest rates for spot rate processes subject to reflecting and absorbing boundaries. Such models preclude negative rates, are consistent with large volatility at low rates, and admit closed form solutions for both bond and European-type derivative security prices. Below, appropriate boundary conditions are derived for spot rates processes that are subject to reflecting and absorbing boundaries. Although it can be demonstrated that spot rate processes with reflecting boundaries can be supported within a general equilibrium framework, we show that reflecting boundaries cannot be placed upon forward rate dynamics without generating arbitrage opportunities. Closed-form bond price solutions for select models are obtained.
Parameterized interfaces for open system verification of product lines

Software product-lines view systems as compositions of features. Each component corresponds to an individual feature, and a composition of features yields a product. Feature-oriented verification must be able to analyze individual features and to compose the results into results on products. Since features interact through shared data, verifying individual features entails open system verification concerns. To verify temporal properties, features must be open to both propositional and temporal information from the remainder of the composed product. This paper addresses both forms of openness through a two-phase technique. The first phase analyzes individual features and generates sufficient constraints for property preservation. The second phase discharges the constraints upon composition of features into a product. We present the technique as well as the results of a case study on an email protocol suite.
Electron-N 2 Cross Sections at Low Energies Calculated Using a Vibrational Averaging Procedure

We calculate e−-N2 elastic and rotational excitation cross sections — within the ground electronic and vibrational state of the target — at low energies and compare our results to available experimental findings. In addition to the static potential we include the effect of polarization via a variationally-determined non-adiabatic polarization potential. We incorporate the effects of exchange exactly employing the linear algebraic method. Using a potential averaging technique we include the effects of the vibrational motion of the target.
A Tribute to Mike Dooley

A personal and professional tribute to Michael P. Dooley, the William S. Potter Professor of Law Emeritus at the University of Virginia School of Law, upon his retirement in 2012.
Purification and characterization of rat kidney UDP-N-acetylglucosamine: alpha-6-D-mannoside beta-1,6-N-acetylglucosaminyltransferase.

In order to investigate the molecular mechanism of the specific increase of UDP-N-acetylglucosamine:alpha-6-D-mannoside beta-1,6-N-acetylglucosaminyltransferase (GlcNAcT-V, EC 2.4.1.155) activity after viral or oncogenic transformation, we have purified the enzyme from a Triton X-100 extract of rat kidney acetone powder. GlcNAcT-V was purified by sequential affinity chromatography using first UDP-hexanolamine-agarose and then a synthetic oligosaccharide inhibitor-agarose column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme revealed two major bands at apparent molecular masses of 69 and 75 kDa. The enzyme was recovered in a 26% final yield with a 450,000-fold increase in specific activity to a Vmax of 18.8 mumols/(mg.min). Enzyme activity was stabilized and enhanced by the addition of 20% glycerol, 0.5 mg/ml IgG, and 0.2 M NaCl. The optimal ranges of pH and Triton X-100 concentrations for enzyme activity were 6.5-7.0 and 1.0-1.5%, respectively. The divalent cations, Mn2+, Ca2+, and Mg2+, were each found to have a negligible (less than 10%) effect on activity; moreover, the enzyme was fully active in the presence of 20 mM EDTA. The Km value of the purified enzyme toward a synthetic trisaccharide acceptor was 90 microM, and the Ki value toward a synthetic active site inhibitor was 140 microM.
Software engineering curriculum issues

A software engineering curriculum must provide the student with: a strong mathematical and theoretical base; problem solving and analysis skills; written and oral communication skills; knowledge of and experience in software engineering principles, processes, and products; knowledge of and experience in measurement, analysis, and control of software processes and products; and an understanding of applicable societal and ethical issues. To effectively address the needs of industry, software engineering education must include experience of applying software engineering principles to nontrivial problems. Here, the author describes how, in an environment of rapidly changing technology and limited educational budgets, delivering a sufficiently robust software engineering educational experience is a challenge.
Testing for Smooth Structural Changes in Time Series Models via Nonparametric Regression

Checking parameter stability of econometric models is a long-standing problem. Almost all existing structural change tests in econometrics are designed to detect abrupt breaks. Little attention has been paid to smooth structural changes, which may be more realistic in economics. We propose a consistent test for smooth structural changes as well as abrupt structural breaks with known or unknown change points. The idea is to estimate smooth time-varying parameters by local smoothing and compare the fitted values of the restricted constant parameter model and the unrestricted time-varying parameter model. The test is asymptotically pivotal and does not require prior information about the alternative. A simulation study highlights the merits of the proposed test relative to a variety of popular tests for structural changes. In an application, we strongly reject the stability of univariate and multivariate stock return prediction models in the postwar and post-oil-shocks periods.
Analysis of secretory patterns of prolactin and gonadotropins during twenty-four hours in a lactating woman before and after resumption of menses

Abstract Twenty-four hour secretory patterns of prolactin, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were obtained on two separate occasions from a woman with late physiologic lactation. The studies were performed 26 and 34 months after her child's birth. During the initial study, she had amenorrhea, and her child suckled 13 per cent of the 24 hour period (Study 1). At the time of the second study, she had resumed regular menses and her child suckled for 7 per cent of the 24 hour period (Study 2). The average concentrations of prolactin during Studies 1 and 2 were 40 ± 1.0 (mean and standard error; No. = 72) and 31 ± 1.4 ng. per milliliter, respectively. The mean plasma prolactin concentration in Study 1 was significantly greater than that in Study 2 (p
Multiregime Sequential Risk-Taking Model of Car-Following Behavior: Specification, Calibration, and Sensitivity Analysis

Car-following models constitute the main component of operational microscopic simulation models and are intended to capture intervehicle interactions on highway sections. Most existing car-following models are deterministic and do not capture the effects of surrounding traffic conditions on the decision-making process of the driver. An extension to a previously introduced sequential risk-taking model is offered to capture the effects of surrounding conditions on driving behavior. The model extension recognizes two behavioral regimes that depend on the complexity of the decision situation associated with the prevailing congestion. With each regime is associated a value function capturing driver preferences for gains associated with a particular acceleration. A probabilistic regime selection mechanism relates the driver's choices to prevailing traffic conditions. The model is calibrated against actual trajectory data. Initial results show that the model provides realistic behavioral patterns previously iden...
Novel endoscopic tools for the evaluation of pancreatic disease: Pancreatoscopy, intraductal ultrasound, and pancreatic cyst fluid analysis

Endoscopic ultrasonography (EUS) has evolved from a diagnostic imaging modality to one that can also be used for invasive diagnostic and therapeutic procedures. These advances are largely due to the introduction of linear scanning instruments, which can be used to place devices into the ultrasound plane of view, permitting various interventions to be performed. The ability of EUS to guide a biopsy needle into lesions that are too small to be identified by CT or MRI or too well encased by surrounding vascular structures to allow percutaneous biopsy secures its role in a variety of clinical settings. The technical evolution in this field has lead to the development of small caliber intraductal ultrasound (IDUS) miniprobes which can be passed through standard endoscopes directly into the bile or pancreatic duct. The small caliber, flexibility, and excellent image quality produced by these high frequency catheters makes them ideal for evaluating a variety of pancreatic disorders. This advance in EUS has been matched by the growing application of intraductal miniature endoscopes (miniscopes) for diagnosing and treating various biliary and pancreatic diseases. The newer miniscopes have a biopsy channel that permits treatment of a growing number of pancreatic disorders which are discussed in detail in this article. Understanding the strengths and limitations of these novel tools maximizes yield and minimizes the risk of unnecessary and more invasive investigations.
Aortic Pseudo Aneurysm Complicating Coarctation Stenting Successfully Treated with a PTFE Balloon Expandable Covered Stent

Percutaneous stenting of both native and recurrent coarctation of the aorta has become an acceptable alternative to surgical repair in most centers throughout the world. Severe complications such as aortic rupture, dissection, and late pseudo aneurysm formation are rare but worrisome complications. In many countries, commercially available balloon expandable covered stents designed for intravascular use are used either for primary stenting, or in treating complications once identified. These endovascular stents, however, are not available in the United States. We report the use of a commercially available covered stent, which has been approved by the Food and Drug Administration for tracheal use, to exclude an aortic pseudo aneurysm that was identified late after stenting a native coarctation.
Impact of a Global Quadratic Potential on Galactic Rotation Curves

We present a conformal gravity fit to the 20 largest of a sample of 110 spiral galaxies. We identify the presence of a universal quadratic potential ${V}_{\ensuremath{\kappa}}(r)=\ensuremath{-}\ensuremath{\kappa}{c}^{2}{r}^{2}/2$ with $\ensuremath{\kappa}=9.54\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}54}{\mathrm{cm}}^{\ensuremath{-}2}$ induced by cosmic inhomogeneities. When ${V}_{\ensuremath{\kappa}}(r)$ is taken in conjunction with both a universal linear potential ${V}_{{\ensuremath{\gamma}}_{0}}(r)={\ensuremath{\gamma}}_{0}{c}^{2}r/2$ with ${\ensuremath{\gamma}}_{0}=3.06\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}30}{\mathrm{cm}}^{\ensuremath{-}1}$ generated by the homogeneous cosmic background and the contribution generated by the local luminous matter in galaxies, the theory then accounts for the rotation curve systematics observed in the entire 110 galaxies, without the need for any dark matter whatsoever. Our study suggests that using dark matter may be nothing more than an attempt to describe global effects in purely local galactic terms. With ${V}_{\ensuremath{\kappa}}(r)$ being negative, galaxies can only support bound orbits up to distances of order ${\ensuremath{\gamma}}_{0}/\ensuremath{\kappa}=100\mathrm{kpc}$, with global physics imposing a limit on the size of galaxies.
The residual spatial abilities of hippocampally lesioned rats can be enhanced by peripheral sympathetic-adrenal interventions.

In order to test the possible effectiveness of peripheral interventions with the adrenergic system for the alleviation of certain disorders that typically follow bilateral hippocampal lesions, rats with bilateral lesions of the hippocampus, the overlying neocortex, or sham operations were tested at two postoperative times in the Morris water maze, a frequently used “spatial task.” Half of the animals in all groups were exposed to the adrenergic manipulations, i.e., a chronic, 7-day, systemic bretylium regime (5 mg/kg) and, in addition, a peripheral injection of norepinephrine (4 μg/kg) 30 min before the start of each training day. The other half received saline chronically and a single saline injection before each training day. Five days of training were given at each of the two training periods. The first began 7 days after surgery while the second began 33 days after surgery. As expected, the hippocampally lesioned animals were severely impaired in the task. The adrenergic treatment produced enhanced performances in the rats with hippocampal lesions at both training sessions, although the improvement was greatest at the later period. Although the animals receiving the pharmacologic treatment located the general area of the hidden platform better than the salinetreated animals with hippocampal lesions, the treated animals were still impaired, swimming directly to the hidden platform on fewer trials than did animals in the other groups.
Studies of the chemical degradation of polysiloxanes by hydrofluoric acid: (2). Poly(tetramethyl-p-silphenylene siloxane-dimethyl siloxane) block copolymers

Abstract Block copolymers of tetramethyl- p -silphenylene siloxane (TMPS) and dimethyl siloxane (DMS) have been selectively degraded with hydrofluoric acid solution. The HF preferentially attacks the SiO bonds, particularly those of the non-crystalline DMS component. The copolymers which were precipitated by the self-seeding technique were etched with 48% HF at 30°C (established as suitable conditions for our work). The crystallinity change on etching these is largest for the sample of lowest TMPS content; it varies from about 20% at zero etching time to 98% after a period of 40 h approximately. The molecular weight, small-angle X-ray period, melting temperature, heat of fusion and degree of crystallinity were all determined as a function of etching time. The correlated results were found to be consistent with a two-phase model in which the DMS component was essentially excluded from the TMPS crystalline core. Some predictions, based on copolymer theories, were found to be consistent with the analysis of the experimental observations.
Charge transfer rates between the ethylenediaminetetra-acetate complexes of Co(II) and Co(III), and of Fe(II) and Fe(III)

Abstract The charge transfer process was found to be immeasurably fast for the system FeY −2 FeY −1 (Y denoting the ethylenediaminetetra-acetate ligand), and, for the system CoY −2 CoY −1 , to obey second-order kinetics with a specific rate constant of 0·75 hr −1 M −1 at 85°C and p H 2. The energy and entropy of activation were found to be 22 kcal/mole and −17 cal/deg.mole, respectively. It is suggested that this difference in lability of seemingly similar systems is explainable primarily in terms of their crystal-field energy-level diagrams and that other charge transfer cases can be correlated similarly.
Oxidative stress in hemodialysis patients: is NADPH oxidase complex the culprit?

Oxidative stress in hemodialysis patients: Is NADPH oxidase complex the culprit? Oxidative stress results from an imbalance between oxidant production, including reactive oxygen species (ROS), reactive nitrogen species (RNS), chlorinated compounds, and antioxidant defense mechanisms. Most reports prove that oxidative stress is present in ESRD patients. Several studies tend to accreditate the hypothesis by which oxidative stress is a strong co-factor for the development of complications related to long-term HD such as atherosclerosis, amyloidosis, malnutrition, anemia, and infection. In order to evaluate the rationale for curative action against oxidative damage in chronic renal failure patients, we reviewed the putative factors involved in this process. Antioxidant systems are severely impaired in uremic patients and gradually altered with the degree of renal failure. Moreover, the inflammatory state caused by the hemoincompatibility of the dialysis system plays a critical role in the activation of NADPH oxidase, aggravating the pro-oxidant status of uremic patients. Prevention of ROS overproduction by improvement of dialysis biocompatibility, an important component of adequate dialysis, might be completed by antioxidant supplementation.
An ultrastructural analysis of cell and matrix differentiation during early limb development in Xenopus laevis

Abstract Early development of the hind limb of Xenopus (stages 44–48) has been analyzed at the level of ultrastructure with emphasis on differentiation of extracellular matrix components and intercellular contacts. By stages 44–45, mesenchyme is separated from prospective bud epithelium by numerous adepidermal granules in a subepithelial compartment (the lamina lucida), a continuous basal lamina and several layers of collagen (the basement lamella). Tricomplex stabilization of amphoteric phospholipid demonstrates that each adepidermal granule consists of several membranelike layers (electron-lucent band 25–30 A; electron-dense band 20–40 A), which are usually parallel to the basal surface of adjacent epithelial cells. Collagen fibrils are interconnected by filaments (35 A in diameter) which stain with ruthenium red. Epithelial cells possess junctional complexes at their superficial borders, numerous desmosomes at apposing cell membranes and hemidesmosomes at their basal surface. Mesenchymal cells predominantly exhibit close contacts (100–150 A separation) with few focal tight junctions at various areas of their surface. By stages 47–48, adepidermal granules are absent beneath bud epithelium and layers of collagen in the basement lamella lose filamentous cross-linking elements. Filopodia of mesenchymal cells penetrate the disorganized matrix and abut the basal lamina. Hemidesmosomes disappear at the basal surface of the epidermis and mesenchymal cells immediately subjacent to epithelium exhibit focal tight junctions and gap junctions at their lateral borders. These structural changes may be instrumental in the epitheliomesenchymal interactions of early limb development. Degradation of oriented collagenous lamellae permits direct association of mesenchymal cell surfaces (filopodia) with surface-associated products of epithelial cells (organized into the basal lamina). Development of structural pathways for intercellular ion and metabolite transport in mesenchyme may coordinate events specific to limb morphogenesis.
ATGC: a database of orthologous genes from closely related prokaryotic genomes and a research platform for microevolution of prokaryotes

The database of Alignable Tight Genomic Clusters (ATGCs) consists of closely related genomes of archaea and bacteria, and is a resource for research into prokaryotic microevolution. Construction of a data set with appropriate characteristics is a major hurdle for this type of studies. With the current rate of genome sequencing, it is difficult to follow the progress of the field and to determine which of the available genome sets meet the requirements of a given research project, in particular, with respect to the minimum and maximum levels of similarity between the included genomes. Additionally, extraction of specific content, such as genomic alignments or families of orthologs, from a selected set of genomes is a complicated and time-consuming process. The database addresses these problems by providing an intuitive and efficient web interface to browse precomputed ATGCs, select appropriate ones and access ATGC-derived data such as multiple alignments of orthologous proteins, matrices of pairwise intergenomic distances based on genome-wide analysis of synonymous and nonsynonymous substitution rates and others. The ATGC database will be regularly updated following new releases of the NCBI RefSeq. The database is hosted by the Genomics Division at Lawrence Berkeley National laboratory and is publicly available at http://atgc.lbl.gov.
Neighborhood effects on BMI trends: Examining BMI trajectories for Black and White women

Racial disparities in obesity among women in the United States are substantial but the causes of these disparities are poorly understood. We examined changes in body mass index (BMI) trajectories for Black and White women as a function of neighborhood disadvantage and racial composition of the neighborhoods within which respondents are clustered. Using four waves of the Americans' Changing Lives (ACL) survey, we estimated multilevel models predicting BMI trajectories over a 16-year period. Even after controlling for individual-level socio-demographics, risk and protective factors, and baseline neighborhood disadvantage and racial composition, substantial racial disparities in BMI persisted at each time point, and widened over time (p < 0.05). Baseline neighborhood disadvantage is associated with BMI and marginally reduces racial disparities in BMI, but it does not predict BMI changes over time. However, without neighborhood-level variables, the BMI trajectory model is misspecified, highlighting the importance of including community factors in future research.
The Measurement of Natural Alpha-Particles Ejected from Solids

Exact expressions for the ionization due to the emission of alpha-particles from radioactive solids are set up and the results of their graphical integration are given. The total ionization per ${\mathrm{cm}}^{2}$ of surface, both with and without absorbers; the variation of ionization with height above the radioactive surface; the ionization from thin films; the ionization from substances containing all members of the U, Th and Ac series, both with and without absorbers; and the counting rate for alpha-particle counting chambers, are given in equations accompanied by appropriate graphs and tables. The older approximate theories break down for actual alpha-particles, particularly those of short range. If $q$ is ion pairs per ${\mathrm{cm}}^{2}$ per sec. formed above the surface of a radioactive solid; $N$, the number of alpha-particles per sec. per ${\mathrm{cm}}^{3}$ emitted in the solid; $k$, ion pairs per alpha-particle of range $R$ in air; and ${R}^{\ensuremath{'}}$, the alpha-particle range in the solid: then $q=\ensuremath{\epsilon}\mathrm{Nk}{R}^{\ensuremath{'}}$, and the numerical coefficient $\ensuremath{\epsilon}$ has values between 0.114 and 0.150 for the alpha-particles from all known radioactive substances.
The Partnering Model: Occupational Therapy Assistant and Occupational Therapy Students Working Together

SUMMARY Establishing a partnering relationship between the occupational therapy assistant (OTA) and the occupational therapist (OT) is imperative in order to create an optimal working environment and deliver effective client care. A developmental model that provides students with opportunities to practice such a relationship has been used by an OTA and OT program in southwestern Ohio. This developmental Partnering Model gives students an opportunity to interact, work as teams, and collaborate during their educational experience. Each aspect of the model provides students with experiential learning opportunities. Educators will serve their OTA and OT students well in providing opportunities for them to develop and practice the skills they will need to create an optimal working environment and deliver effective client care as occupational therapy practitioners.
The fine structure of differentiating muscle in the salamander tail

Thin methacrylate sections of developing tails of Amblystoma opacum larvae were examined in the electron microscope and a series of stages in the differentiation of the myotome musculature was reconstructed from electron micrographs and earlier light microscopic studies of living muscle. The earliest muscle cell precursor that can be clearly identified is a round or oval cell with abundant cytoplasm containing scattered myofilaments and free ribonucleoprotein granules, but little endoplasmic reticulum. These cells sometimes form a syncytium and they may also be fused with adjacent formed muscle fibers by lateral processes. Nuclei are large and nucleoli are prominent. This cell, called a “myoblast” here, is distinctly different in its appearance from the adjacent mesenchymal cells which have abundant granular endoplasmic reticulum. The earliest myofilaments are of both the thick and thin varieties and are distributed in a disorganized fashion in the cytoplasm. These filaments are similar to the actin and myosin filaments described by Huxley and they are present in the cytoplasm at an earlier stage of differentiation than heretofore suspected from light microscopy studies. The first myofibrils are a heterogeneous combination of thick and thin filaments and dense Z bands and are not homogeneous as so many light microscopists have contended. As development progresses, cross striations become more orderly and definitive sarcomeres are formed. Thereafter, new myofilaments and Z bands seem to be added to the lateral surfaces and distal ends of existing myofibrils. Free ribonucleoprotein granules are a prominent part of the myoblast cytoplasm and are found in close association with the differentiating myofilaments in all stages of development. In early muscle fibers and some of the formed fibers, similar granules are often concentrated in the I bands. A theory of myofilament differentiation based on current concepts of the role of ribonucleoprotein in protein synthesis is presented in the discussion. Stages in myofibril formation and possible relationships of the filaments in developing muscle cells to other types of cytoplasmic filaments are also discussed.
Five forms of arginase in human tissues

Five forms of arginase, A1, A2, A3, A4, and A5, were found to be present in human tissues. The molecular weight of all these forms is the same, 120,000, but they differ in the behavior on DEAE- and CM-cellulose, electrophoretic mobility, isoelectric point, and immunochemical properties. Forms A1 from kidney and A5 from liver show complete immunological incompatibility, whereas forms A2 from liver, A3 from salivary gland, and A4 from kidney exhibit partial incompatibility with respect to each other and to forms A1 and A5.
Real-Time Assessment of the Columbia-Snake River Extended Lock Outage: Process and Impacts

Waterborne movements, one of the more economical methods of all modes of transportation, are a key component of the multimodal transportation system in the Pacific Northwest of the United States. The Columbia-Snake River system in the Pacific Northwest underwent a sustained lock outage from December 2010 to March 2011. This outage eliminated barge transportation on much of the upper Columbia River and all of the Snake River. Shippers, carriers, and ports on the river projected the impact of the loss of a major mode of transportation to be substantial and the impact on demands of other modes of transportation to be dramatic. A study done in real time took advantage of the disruption of the Columbia-Snake system to determine the dynamics of the overall process and the impacts of such a change induced by an outage. The study reported specifically on the Pacific Northwest wheat industry, 75% of downriver commodity movement. A transportation disruption like that of the extended lock outage on the Columbia-Snak...
Stable long-distance pulse propagation in nonlinear optical fibers using periodically-spaced parametric amplifiers

Parametric amplifiers have been proposed [1] as an alternative to lumped erbium-doped amplifiers for long-distance optical pulse propagation in fibers. While filtering techniques [2] have been demonstrated to suppress the bit-rate limitation caused by the Gordon-Haus jitter [3] — the random walk of solitons caused by spontaneous emission noise of the erbium amplifiers, or by initial fluctuations in the soliton parameters — a chain of lumped parametric amplifiers should have higher possible bit-rates because no such amplifier noise is present [1].
Providing insight into group process

This paper presents ongoing work towards development of a reporting tool for providing group work facilitators with insight into group work processes. The work includes three main phases, including feasibility testing, initial design based on data analysis of interviews, and iterative design based on user testing. Here, the work completed to date on the first two phases is presented along with ideas for the last phase of the work.
Pelvic organ support in nulliparous pregnant and nonpregnant women: A case control study ☆

Abstract Objective: Our purpose was to compare pelvic organ support in nulliparous pregnant and nonpregnant women at a single institution. Study Design: This was a case-control study. Pregnant patients and nonpregnant control subjects were matched according to age and race. Subjects underwent pelvic organ support evaluation by use of the pelvic organ prolapse quantification (POPQ) examination as part of routine prenatal or gynecologic care.The Pearson χ 2 statistic was used for statistical analysis, with a P value of 5% set for significance. Results: A total of 21 pregnant and 21 nonpregnant nulliparous women between the ages of 18 and 29 years were included. All patients in the nonpregnant group had a POPQ stage of 0 or 1, whereas 47.6% of the pregnant subjects had POPQ stage 2 ( P Conclusions: In nulliparous women, pregnancy is associated with increased POPQ stage compared with nonpregnant control subjects. (Am J Obstet Gynecol 2002;187:99-102.)
RETENTION OF GRADUATE STUDENTS IN SOCIAL WORK: AN ISSUE OF ENROLLMENT MANAGEMENT FOR THE NINETIES '

Summary.-The retention of graduate students in social work is a key issue of management of enrollment for the decade of the nineties due to the anticipated enrollment shortage as well as the changing demographic characteristics of graduate students. In light of this issue, a study was conducted to assess the presence and structure of formal mechanisms to monitor students who "drop out" and/or "stop out" of gaduate programs. Also, an attempt was made to document and identify the numbers and types of smdents who are especially vulnerable to interruption in programs. Analysis indicates that, although formal mechanisms to track students are in place in schools of social work, there is little evidence of interruption of students' programs. While respondents suggested that they monitor especially vulnerable students, they did not provide specific information on identifying that group. These results raise further questions about management of enrollment in general and how the issue of retention in particular may be important to survival and/or development of graduate programs.
Non-small Cell Lung Cancer Treatment Receipt and Survival Among African-Americans and Whites in a Rural Area

Data on racial disparities among lung cancer patients in rural areas are scarce. We examined differences in treatment receipt and survival among African-American (AA) and Non-Hispanic White (NHW) non-small cell lung cancer (NSCLC) patients residing in Southwest Georgia (SWGA)—a primarily rural 33-county area; population 700,000. Medical records for 934 SWGA NSCLC patients diagnosed in 2001–2003 were used to extract information on age, race, marital status, insurance coverage, comorbidities, and treatment. Information pertaining to socioeconomic status, urban/rural residence, and survival was obtained from the cancer registry. Multivariable logistic regression analyses examined the relation of various patient and disease characteristics to receipt of tumor-directed therapy. Cox regression models were used to assess determinants of survival. Treatment receipt was associated with age, marital status, comorbidities, and disease stage in most analyses. No associations were observed between race and either surgery [odds ratio (OR) 0.83, 95 % confidence interval (CI) 0.49–1.39] or radiation (OR 0.72; 95 % CI 0.52–1.00). NHW patients were more likely to receive no treatment at all (OR 1.50, 95 % CI 1.01–2.23). There was no racial difference in survival (hazard ratio = 1.07, 95 % CI 0.90–1.26). Effects of insurance and treatment on survival were most pronounced within 6 months post-diagnosis, but were attenuated over time. We found no evidence of racial disparities in survival and, in some analyses, a decreased likelihood of treatment receipt among NHW NSCLC patients compared to AA. The results from SWGA stand in contrast to studies that applied different methodologies and were conducted elsewhere.
Battles of the Revolutionary War, 1775-1781

Bunker Hill Quebec Trenton and Princeton Brandywine Oriskany Saratoga: Freemans Farm and Bemis Heights Kings Mountain Cowpens Guilford Courthouse The Chesapeake Capes.
Energy-Momentum Structure Form Factors of Particles

By emphasizing the analogy between mass and charge as sources of fields, we are led to examine the mechanical structure of a particle in terms of the matrix elements $〈{\mathrm{p}}^{\ensuremath{'}}|{\ensuremath{\theta}}_{\ensuremath{\alpha}\ensuremath{\beta}}(0)|\mathrm{p}〉$, where ${\ensuremath{\theta}}_{\ensuremath{\alpha}\ensuremath{\beta}}(x)$ is the total energy-momentum tensor, just as the matrix elements $〈{\mathrm{p}}^{\ensuremath{'}}|{j}_{\ensuremath{\alpha}}(0)|\mathrm{p}〉$ of the current operator ${j}_{\ensuremath{\alpha}}(x)$ define its electromagnetic structure. Although the off-diagonal matrix elements $〈{\mathrm{p}}^{\ensuremath{'}}|{\ensuremath{\theta}}_{\ensuremath{\alpha}\ensuremath{\beta}}(0)|\mathrm{p}〉$ are not accessible to direct experimental observation, the diagonal element $〈\mathrm{p}|{\ensuremath{\theta}}_{\ensuremath{\alpha}\ensuremath{\beta}}(0)|\mathrm{p}〉$ is just proportional to the total mass. Consequently, we can study the contributions to the total mass in terms of vertex functions instead of propagators and, using the techniques of dispersion theory, relate the contribution to the total mass to integrals over physical scattering processes. We examine electrodynamics and the pion-nucleon interaction in perturbation theory and show how the mass divergences emerge as a consequence of the high-energy behavior of the Coulomb amplitude and the nucleon-nucleon scattering amplitude. Finally, using elastic unitarity, we can relate mass splittings in a multiplet to integrals over the differences in $S$-wave phase shifts.
Space charge regions at silver halide surfaces: Effects of divalent impurities and halogen pressure

Abstract The model first proposed by Poeppel and Blakely to account for equilibrium space charge regions in ionic crystals is extended to include effects of mobile divalent impurities. Equations are developed that account for impurities segregating to free surfaces of crystals of the AgCl type. Numerical computations have been performed and the results indicate the variation with temperature of the potential difference across the surface space charge region. The importance of accounting for the density and energy of surface sites is demonstrated. The calculation includes effects of varying the doping level of the impurities as well as the binding energy of the impurity-vacancy complex. The effect of a chlorine atmosphere on intrinsic crystals is discussed and the variation of the chemical potential of the silver ions with Cl 2 pressure is presented.
Women of a certain age: “Second wave” feminists reflect back on 50 years of struggle in the United States

Synopsis Using social movement theory, this study explores the lives of 31 women in the U.S. who were activists in the “second wave” feminist movement in order to understand how aging activists currently make sense of the victories and setbacks in the struggle for gender justice. Findings from in-depth interviews show that veteran feminists possess a profound ambivalence about the impact of the modern feminist movement. Along with feelings of empowerment and pride, many older women activists carry feelings of outrage at movement backlash; anger at the loss of systemic analyses among younger generations; grief around interpersonal trauma experienced as activists; and a sense of marginalization. These findings give voice to a cohort whose unique perspectives are critical for our understanding of the social history of American feminisms, and contribute to knowledge of how freedom fighters think and feel about social movement participation once the period of mass mobilization has ended.
Simple Derivation of the Baxter-Model Free Energy

Starting with some observations due to A. B. Zamolodchikov, a short cut to the determination of the Baxter (eight-vertex) -model free energy is developed. The method involves factorizable $S$ matrices in 1 + 1 dimensions, which are briefly reviewed. If the method generalizes, we may associate with each known $S$ matrix a Baxter-like model with a known free energy.
Peer-to-peer streaming over dynamic random Hamilton cycles

We are motivated by the problem of designing a simple distributed algorithm for Peer-to-Peer streaming applications that can achieve high throughput and low delay, while allowing the neighbor set maintained by each peer to be small. While previous works have mostly used tree structures, our algorithm constructs multiple random directed Hamilton cycles and disseminates content over the superposed graph of the cycles. Compared with the algorithms constructing trees, the complexity to dynamically update the network topology in response to peer churn does not increase with the network size under our algorithm. We show that it is possible to achieve the maximum streaming capacity even when each peer only transmits to and receives from Θ(1) neighbors. Further, we show that the proposed algorithm achieves the streaming delay of Θ(logN) when the streaming rate is less than (1 − 1/K) of the maximum capacity for any fixed constant K ≥ 2.