cssi/SciSciGPT-SciSciNet huggingface dataset:
Prediction of models for ordered solvent in macromolecular structures by a classifier based upon resolution-independent projections of local feature data.

Current software tools for the automated building of models for macro­molecular X-ray crystal structures are capable of assembling high-quality models for ordered macromolecule and small-molecule scattering components with minimal or no user supervision. Many of these tools also incorporate robust functionality for modelling the ordered water molecules that are found in nearly all macromolecular crystal structures. However, no current tools focus on differentiating these ubiquitous water molecules from other frequently occurring multi-atom solvent species, such as sulfate, or the automated building of models for such species. PeakProbe has been developed specifically to address the need for such a tool. PeakProbe predicts likely solvent models for a given point (termed a `peak') in a structure based on analysis (`probing') of its local electron density and chemical environment. PeakProbe maps a total of 19 resolution-dependent features associated with electron density and two associated with the local chemical environment to a two-dimensional score space that is independent of resolution. Peaks are classified based on the relative frequencies with which four different classes of solvent (including water) are observed within a given region of this score space as determined by large-scale sampling of solvent models in the Protein Data Bank. Designed to classify peaks generated from difference density maxima, PeakProbe also incorporates functionality for identifying peaks associated with model errors or clusters of peaks likely to correspond to multi-atom solvent, and for the validation of existing solvent models using solvent-omit electron-density maps. When tasked with classifying peaks into one of four distinct solvent classes, PeakProbe achieves greater than 99% accuracy for both peaks derived directly from the atomic coordinates of existing solvent models and those based on difference density maxima. While the program is still under development, a fully functional version is publicly available. PeakProbe makes extensive use of cctbx libraries, and requires a PHENIX licence and an up-to-date phenix.python environment for execution.
Becoming In/Out of Place: Doing Research in Chinatown as a Chinese Female Geographer in the Era of Transnationalism

Many scholars have discussed reflexivity and positionality in terms of relationship between researchers and the researched subjects. Rarely has the relationship between researchers and the research...
Faculty Internships: Bridging the Gap between Education and Industry

(1994). Faculty Internships: Bridging the Gap between Education and Industry. Hospitality & Tourism Educator: Vol. 6, No. 4, pp. 68-72.
Bajacanthus immaculatus: A New Hoplinine Genus and Species of Stilt Bug (Hemiptera: Heteroptera: Berytidae) from Baja California Sur, Mexico, with a Revised Key to Genera of the Tribe

The new stilt bug genus Bajacanthus, n. gen., and new species B. immaculatus, n. sp. are described from the Vizcaino Peninsula in Baja California Sur, Mexico. The berytid was discovered on the recently described endemic plant, Bajacalia moranii B. L. Turner (Asteraceae). A diagnosis, description, digital images of the adult male and female, the male genitalia capsule, and parameres are provided to facilitate recognition. A discussion of relationships is given and a revised key to the genera of the tribe Hoplinini (Gampsocorinae) is provided.
Comparing a Machine Learning Predictive Model with Federal Transit Administration (FTA)’s Default Useful Life Benchmark to Predict Replacement Costs for Revenue Vehicles:

A predictive model is developed that uses a machine learning algorithm to predict the service life of transit vehicles and calculates backlog and yearly replacement costs to achieve and maintain tr...
A Mosquito-Borne Disease Model with Non-exponentially Distributed Infection and Treatment Stages

Most epidemiological models for mosquito-borne disease assume exponentially distributed residence times in disease stages in order to simplify the model formulation and analysis. However, these models do not allow for accurate description of the interaction between drug concentration and pathogen load within hosts. To improve this, we formulate a model by considering arbitrarily distributed sojourn for various disease stages. The model formulation is presented using two proven equivalent approaches: integral equations and partial differential equations. Analysis of the model includes the existence of equilibrium solutions and stability, which are shown to be dependent on whether the control reproduction number $${\mathcal {R}}_c$$ is less or greater than 1. It is also shown that, when the general distributions are replaced by gamma distributions, the system of integral equations can be reduced to a system of ODEs, which has some non-trivial characteristics which are only captured by non-exponential distributions for disease stages.
Deep Brain Stimulation Target Selection in Co-Morbid Essential Tremor and Parkinson’s Disease

Clinical Vignette: A 64-year-old man with essential tremor (ET) and Parkinson’s disease (PD) presented with medically refractory, large amplitude, debilitating rest and action tremor in his extremities. Clinical Dilemma: Ventral intermediate nucleus of the thalamus (VIM) deep brain stimulation (DBS) improves tremor in ET and PD but does not ameliorate bradykinesia and rigidity in PD. The comparative efficacy of subthalamic nucleus (STN) DBS in managing action ET tremor remains unclear. Clinical Solution: Bilateral STN was selected as the DBS target. Moderate improvement in rest tremor and mild improvement in action tremor were noted following initial programming. Gap In Knowledge: There are no head-to-head trials to guide DBS target selection in patients with both ET and PD. Current evidence is limited to a few small head-to-head trials that have demonstrated equivalent efficacy in tremor reduction in PD patients using VIM as DBS target and in ET patients using STN. Expert Commentary: Due to limited evidence, DBS treatment of complex cases, such as combined Parkinson’s disease and essential tremor, remains based on expert consensus at each institution. Further multi-approach efforts, using imaging, electrophysiologic, and animal data, will be needed to answer the identified gap in knowledge. Highlights: There is limited evidence to guide deep brain target selection in patients with essential tremor and Parkinson’s disease. We review existing literature and propose strategies to manage tremor in these patients.
Anomalously low radiocarbon content of modern n-alkanes

Abstract Compound-specific radiocarbon (14C) ages of lipid biomarkers commonly pre-date co-occurring macrofossils or sediment matrices in lacustrine and marine sedimentary sequences. Hypothetically, this age offset is the result of long residence and transport times of organic matter in the terrestrial realm and is referred to as ‘pre-aging’. Here we measure the 14C content of n-alkanes extracted from living leaf tissue of six different plant species. In all samples, the modern n-alkanes contained anomalously low 14C content resulting in apparent radiocarbon ages ranging from ∼ 530 to 1580 cal yr B.P. while bulk tissue samples yielded the expected modern 14C ages. These results indicate a potentially strong fractionation against 14C during lipid biosynthesis also documented for 13C and 2H stable isotope systems. This fractionation could, at least partially, explain observed age offsets between lipid biomarkers and co-occurring sediments.
Point-of-care ultrasound during the COVID-19 pandemic: A multidisciplinary approach between intensivists and echocardiographers.

Purpose The coronavirus disease-2019 (COVID-19) led to a large influx of critically ill patients and altered echocardiography laboratory workflow. We developed a point-of-care ultrasound (POCUS) first approach to patients requiring echocardiography and describe our workflow and findings. Methods We performed a single-center retrospective analysis of all POCUS studies performed on critically ill patients with COVID-19. Sonography was performed by intensivists, uploaded and archived, and rapidly reviewed by echocardiographers. We evaluated each study based on the number of views obtained. Additionally, we provide a description of the workflow during the COVID-19 surge at a tertiary care hospital in New York City. Results Fifty patients had POCUS studies performed by intensivists and reviewed by echocardiographers obviating the need for sonographer-performed studies. Of the 48 cardiac POCUS studies, 17% of patients had 4 of 4 standard views available while 53% had 3 of 4 standard views. The parasternal long-axis view was obtained on 81%, subxiphoid view on 79%, apical 4-chamber view on 71%, and parasternal short-axis view on 63% of patients. Conclusions Our POCUS workflow allowed intensivists to perform cardiac sonography for rapid bedside diagnosis of pathology with immediate interpretation performed by echocardiographers. At least 3 views were obtained in the majority of cases.
Attention and distraction in the modular visual system of a jumping spider

Animals must selectively attend to relevant stimuli and avoid being distracted by unimportant stimuli. Jumping spiders (Salticidae) do this by coordinating eyes with different capabilities. Objects are examined by a pair of high-acuity principal eyes, whose narrow field of view is compensated for by retinal movements. The principal eyes overlap in field of view with motion-sensitive anterior-lateral eyes, which direct their gaze to new stimuli. Using a salticid-specific eyetracker, we monitored the gaze direction of the principal eyes as they examined a primary stimulus. We then presented a distractor stimulus visible only to the ALEs and observed whether the principal eyes reflexively shifted their gaze to it or whether this response was flexible. Whether spiders redirected their gaze to the distractor depended on properties of both the primary and distractor stimuli. This flexibility suggests that higher-order processing occurs in the management of the attention of the principal eyes.
Performance, Hemodynamics, and Stress in a Two-Day Vigilance Task: Practical and Theoretical Implications.

ObjectiveTo explore vigilance task performance, cerebral blood flow velocity (CBFV), workload, and stress in a within-subjects, two-session experiment.BackgroundVigilance, or sustained attention, t...
Talk is cheap?! The value of a ban on product simulations and renderings on a crowdfunding platform

We exploit the 20 September 2012 intervention on Kickstarter where projects in the Hardware and Project Design categories, but not in other categories, were prohibited from presenting simulations a...
Racist compared to what? the myth of white wokeness

Citizens of the contemporary Unites States are faced with the cognitive dissonance of a society which claims to reject the racist, sexist, homophobic and ableist ways of our ancestors, while daily ...
Resistance and Submission: A Case Study of the Training of DV Advocates

Domestic violence work typically happens within the confines of significant macro forces that shape most social work practice, including but not limited to neoliberalism, criminalization and profes...
Multiple regulatory mechanisms control the production of CmrRST, an atypical signal transduction system in Clostridioides difficile

ABSTRACT Clostridioides difficile, an intestinal pathogen and leading cause of nosocomial infection, exhibits extensive phenotypic heterogeneity through phase variation by site-specific recombination. The signal transduction system CmrRST, which encodes two response regulators (CmrR and CmrT) and a sensor kinase (CmrS), impacts C. difficile cell and colony morphology, surface and swimming motility, biofilm formation, and virulence in an animal model. CmrRST is subject to phase variation through site-specific recombination and reversible inversion of the ‘cmr switch’, and expression of cmrRST is also regulated by c-di-GMP through a riboswitch. The goal of this study was to determine how the cmr switch and c-di-GMP work together to regulate cmrRST expression. We generated “phase locked” strains by mutating key residues in the right inverted repeat flanking the cmr switch. Phenotypic characterization of these phase locked cmr-ON and -OFF strains demonstrates that they cannot switch between rough and smooth colony morphologies, respectively, or other CmrRST-associated phenotypes. Manipulation of c-di-GMP levels in these mutants showed that c-di-GMP promotes cmrRST expression and associated phenotypes independent of cmr switch orientation. We identified multiple promoters controlling cmrRST transcription, including one within the ON orientation of cmr switch and another that is positively autoregulated by CmrR. Overall, this work reveals a complex regulatory network that governs cmrRST expression and a unique intersection of phase variation and c-di-GMP signaling. These findings suggest that multiple environmental signals impact the production of this signaling transduction system. IMPORTANCE Clostridioides difficile is a leading cause of hospital-acquired intestinal infections in the U.S. The CmrRST signal transduction system controls numerous physiological traits and processes in C. difficile, including cell and colony morphology, motility, biofilm formation, and virulence. Here we define the complex, multi-level regulation of cmrRST expression, including stochastic control through phase variation, modulation by the second messenger c-di-GMP, and positive autoregulation by CmrR. The results of this study suggest that multiple, distinct environmental stimuli and selective pressures must be integrated to appropriately control cmrRST expression.
Evolution of Telehealth Technology, Evaluations, and Therapy: Effects of the COVID-19 Pandemic on Pediatric Speech-Language Pathology Services.

Purpose: Telehealth services experienced exponential growth during the COVID-19 pandemic. This survey examined the resulting evolution in the technology, connectivity, implementation of services, a...
The Search for American Political Development

In recent years, American political development has claimed the attention of a growing band of political scientists, and scholars have begun to speak of 'APD' as a subfield within the discipline. This book provides a justification for studying politics historically, not only for what it reveals about the roots of political affairs at the present time but what it teaches about politics as an ongoing activity in time, anytime. Placing the character of political institutions at the center of analysis, Orren and Skowronek survey past and current scholarship and attempt to outline a course of study for the future.
Prediction of Delinquent and ADM Behavior from Other Delinquent and ADM Behavior

In previous chapters we examined the common correlates of delinquent and ADM behavior, and (in Chapter 3) the direct correlation between different types of delinquent and ADM behavior. In Chapter 6 in particular, we found that although delinquency, substance use, and mental health problems share no direct causal influence common to all three types of behavior, all three had some indirect influences in common. In the present chapter we turn to the prediction of the different types of delinquent and ADM behaviors directly from one another. We do not suggest here that one type of behavior causes another, as, for example, we suggested in Chapter 6 that delinquent peer group bonding (DPGB) causes or leads to delinquent behavior. Instead, we are simply asking to what extent our knowledge of one type of behavior better enables us to predict another.
The pathways of nitrogen fixation.

Publisher Summary Biological nitrogen fixation is the enzymic reduction of atmospheric nitrogen to ammonia. Along with the scientific interest of nitrogen fixation as a fundamental biochemical reaction, it is also of great ecological and agricultural importance because it is the most important source of the metabolizable nitrogen needed by all living organisms. Nitrogen fixation is catalyzed by nitrogenase, which requires energy in the form of ATP and a biologically strong reductant for the formation of ammonia. Moreover, the chapter also gives a general review of the field of nitrogen fixation with emphasis on recent developments. The study of the biochemical genetics of nitrogen fixation can yield important basic knowledge regarding the pathway, mechanism, and regulation of this process. Furthermore, in symbiotic nitrogen fixation, both plant and host bacterium carry genetic information relevant to this process, making the genetics of the system complex. Finally, understanding of the biochemical relationships in symbiotic nitrogen fixation might allow the extension of this process to non-leguminous agricultural crops.
Magnetic resonance imaging of the brainstem and cranial nerves

Ten normal human volunteers and 44 patients with pathology of the brainstem or cranial nerves were scanned using a. 3 Tesla permanent MR imaging system. MR images were obtained of the cranial nerves and brainstem using various spin-echo pulse sequences and scanning planes. 4 mm thick sections with .75 mm pixels on a 256 display matrix were used whenever possible. The normal MR images were correlated with thin section cryodissection specimens of fresh human cadavers. Brainstem structures including major nuclei and tracts were then identified. The cranial nerves were followed through the subarachnoid cisterns and the base of the skull. Pathological involvement of the brainstem by tumors, infarcts, and demyelinating disease was well shown and correlated with clinical findings. Examples of optic glioma, fifth, eighth, and twelfth nerve schwannomas as well as other cranial nerve pathology were also demonstrated. Magnetic resonance produces excellent images of cranial nerves and brainstem with high contrast resolution. Unlike CT, there is no beam hardening artifact from bone. T1 weighted images maximize brainstem-CSF contrast and are useful for demonstrating the external anatomy of the brainstem and cranial nerves. The T2 weighted images show internal brainstem anatomy, CSF within neural foramina, and highlight many pathological conditions.
Interaction of mitogenic signaling pathways in medulloblastoma

SY33-5 Medulloblastoma is the most common malignant brain tumor in children. It is thought to result from transformation of granule cell precursors (GCPs) in the developing cerebellum, but little is known about the early stages of the disease. We have identified a pre-neoplastic stage of medulloblastoma in patched heterozygous mice, a model of the human disease. We show that pre-neoplastic cells are present in the majority of patched mutants, although only 16% of these mice develop tumors. Pre-neoplastic cells, like tumor cells, exhibit activation of the Sonic hedgehog pathway and constitutive proliferation. Importantly, they also lack expression of the wild-type patched allele, suggesting that loss of patched is an early event in tumorigenesis. While pre-neoplastic cells resemble GCPs and tumor cells in many respects, they have a distinct molecular signature. Genes that mark the pre-neoplastic stage include regulators of migration, apoptosis and differentiation, processes critical for normal development but previously unrecognized for their role in medulloblastoma. The identification and molecular characterization of pre-neoplastic cells provides insight into the early steps in medulloblastoma formation, and may yield important markers for early detection and therapy of this disease.
Multiple Forms of Rat Testicular Androgen Binding Protein: Physicochemical Properties and the Effect of Ca++

The presence of two forms of androgen binding protein (ABP) was confirmed in rat testicular cytosol. Each was distinctly separated from the other by DEAE-cellulose chromatography and showed a single peak with a slightly different Rf on polyacrylamide gel electrophoresis (PAGE) (0.49 ± 0.03 (mean ± SD) for one (ABP I) and 0.55 ± 0.04 for the other (ABP II)). ABP I retained 90% of its binding capacity for dihydrotestosterone for 2 hours at 60 C, whereas ABP II lost more than 90% of its binding capacity within 10 minutes at 60 C. Other physicochemical properties of the two were very similar: identical values of Einstein's stokes radius of 47 A; sedimentation coefficient of 4.6–4.7 S; 5–8 minutes as half dissociation time of [3H]-dihydrotestosterone-ABP complex; identical elution positions from Sephadex G-200 chromatography; and association constants for dihydrotestosterone of 2.1 × 108 M −1 for ABP I and 4.0 × 108 M 1 for ABP II. The order of binding affinity of the two forms was dihydrotestosterone > testosterone > estradiol-17β >progesterone. The presence of Ca++ in the elution buffer caused the two forms to elute at lower ionic concentration off DEAE-cellulose. This was reversed by the removal of Ca++ with the addition of (ethylenebis (oxyethylene nitrilo)) tetraacetic acid.
Does the Weighted Cost of Capital Associate with Returns on Operating and Financial Assets with Investor Anticipation or Reaction? [And Do Operating and Financial Assets Have Synergy?]

The relation of firm accounting information and investor decision-making is a key financial accounting issue. Firm accounting information is a result of management's decisions. This study focuses on the investors' perspective of the consequences of management's actions with respect to the cost of firm capital and the returns on assets. Conventional thought hypothesizes management to maximize the return on asset investments within the rubric of minimizing the firm weighted average cost of capital. Within this framework, we investigate financial statement relevance with regard to whether investors anticipate or react to firm asset investment returns. The study also examines the existence of synergy between firm operating and financial asset returns. Because leverage is a central capital structure factor, we also investigate the leverage impact on the relation between investor supplied fund costs and asset returns.
Unifying convergence and no-regret in multiagent learning

We present a new multiagent learning algorithm, RVσ(t), that builds on an earlier version, ReDVaLeR . ReDVaLeR could guarantee (a) convergence to best response against stationary opponents and either (b) constant bounded regret against arbitrary opponents, or (c) convergence to Nash equilibrium policies in self-play. But it makes two strong assumptions: (1) that it can distinguish between self-play and otherwise non-stationary agents and (2) that all agents know their portions of the same equilibrium in self-play. We show that the adaptive learning rate of RVσ(t) that is explicitly dependent on time can overcome both of these assumptions. Consequently, RVσ(t) theoretically achieves (a') convergence to near-best response against eventually stationary opponents, (b') no-regret payoff against arbitrary opponents and (c') convergence to some Nash equilibrium policy in some classes of games, in self-play. Each agent now needs to know its portion of any equilibrium, and does not need to distinguish among non-stationary opponent types. This is also the first successful attempt (to our knowledge) at convergence of a no-regret algorithm in the Shapley game.
A prospective comparison of radical retropubic and robot-assisted prostatectomy: experience in one institution.

The authors from the Vattikuti Institute in the USA report a prospective comparison of radical prostatectomy and robot-assisted prostatectomy. They found that the robot-assisted procedure was safer, and yielded favourable oncological and functional results. They also present work in association with the Department of Urology in Mansoura into robot-assisted radical cystoprostatectomy and urinary diversion, and point out the advantages and disadvantages associated with performing the most complex types of urinary diversion. There is also an interesting paper relating to the association between sexual factors and prostate cancer, from authors in institutions in Australia, New Zealand and Italy. They found that in a case-control study of men aged <70 years, ejaculatory frequency was negatively associated with the risk of prostate cancer. Technology has made many contributions to the management of urological patients. The classic example is that of urinary stone management. Authors from the USA evaluated cyroablation of renal carcinoma in patients with solitary kidneys. They are encouraged by their results and suggest that there is merit in this treatment, but indicate the need for a longer follow-up. OBJECTIVE To prospectively compare standard radical retropubic prostatectomy (RRP) and the robotically assisted Vattikuti Institute prostatectomy (VIP) in the management of localized prostate cancer. PATIENTS AND METHODS The study was a single-institution, prospective, unrandomized comparison of histopathological, and functional outcomes, at baseline and during and after surgery, in 100 patients undergoing RRP and 200 undergoing VIP. RESULTS While the variables before surgery, the operative duration (163 vs 160 min) and pathological stages were comparable, there were significant differences in the measured outcomes. The blood loss was 910 and 150 mL for RRP and VIP, respectively, and transfusion was greater after RRP (67% vs none; both P < 0.001). There were four times as many complications after RRP (20% vs 5%, P < 0.05), the haemoglobin level at discharge was lower (100 vs 130 g/L, P < 0.005) and the hospital stay longer (3.5 vs 1.2 days; P < 0.05). Most (93%) of VIP and none of the RRP patients were discharged within 24 h (P < 0.001); the duration of catheterization was twice as long after RRP (15.8 vs 7 days; P < 0.05). Positive margin was more frequent after RRP (23% vs 9%, P < 0.05). After VIP, patients achieved continence and return of erections more quickly than after RRP (160 vs 44, and 180 vs 440 days, both P < 0.5). The median return to intercourse was 340 days after VIP but after RRP half the patients have as yet not resumed intercourse at 700 days (P < 0.05). CONCLUSIONS The VIP procedure appears to be safer, less bloody and requires shorter hospitalization and catheterization. The oncological and functional results were favourable in patients undergoing VIP.
Autism Speaks Toolkits Resources for Busy Physicians

Given the increased prevalence of autism spectrum disorders (ASD), it is likely that busy primary care providers (PCP) are providing care to individuals with ASD in their practice. Autism Speaks provides a wealth of educational, medical, and treatment/intervention information resources for PCPs and families, including at least 32 toolkits. This article serves to familiarize PCPs and families on the different toolkits that are available on the Autism Speaks website. This article is intended to increase physicians' knowledge on the issues that families with children with ASD frequently encounter, to increase their ability to share evidence-based information to guide treatment and care for affected families in their practice.
Noncompleting Drug Court Clients: A Qualitative Assessment of Harm Reduction Effects

Most drug court program evaluations focus on successful clients. The purpose of this study was to understand how partial exposure to drug court affected clients who failed to complete the program. Those that participated at least 30 days (N = 30) were interviewed. A medical as-treated design and a harm reduction paradigm were used as frameworks to determine effects. Moderate harm reduction results were found with non-completers. Examining clients who fail to complete drug court is critical to understanding the full efficacy of the therapeutic jurisprudence model.
The Political Economy of Cigarette Taxation

To date, the literature on cigarette excise taxation has focused on demand, its elasticity, and state revenue from the taxes. By examining the factors that influence cigarette excise tax rates across U.S. states, this paper helps to fill the under-researched aspect of cigarette taxation. Empirical evidence presented here supports the special interest hypothesis when analyzing between-state tax rate differentials. Using a spatial econometric framework, this paper illustrates that the effect of special interest groups is six times greater once spillover effects are taken into consideration. Finally, time splits of the data are also presented to reveal stark changes in the determinants of state-levied cigarette taxes over time.
Scarless genome editing and stable inducible expression vectors for Geobacter sulfurreducens

Metal reduction by members of the Geobacteraceae is encoded by multiple gene clusters, and the study of extracellular electron transfer often requires biofilm development on surfaces. Genetic tools that utilize polar antibiotic cassette insertions limit mutant construction and complementation. In addition, unstable plasmids create metabolic burdens that slow growth, and the presence of antibiotics such as kanamycin can interfere with the rate and extent of Geobacter biofilm growth. We report here genetic system improvements for the model anaerobic metal-reducing bacterium Geobacter sulfurreducens. A motile strain of G. sulfurreducens was constructed by precise removal of a transposon interrupting the fgrM flagellar regulator gene using SacB/sucrose counterselection, and Fe(III) citrate reduction was eliminated by deletion of the gene encoding the inner membrane cytochrome imcH. We also show that RK2-based plasmids were maintained in G. sulfurreducens for over 15 generations in the absence of antibiotic selection in contrast to unstable pBBR1 plasmids. Therefore, we engineered a series of new RK2 vectors containing native constitutive Geobacter promoters, and modified one of these promoters for VanR-dependent induction by the small aromatic carboxylic acid vanillate. Inducible plasmids fully complemented ΔimcH mutants for Fe(III) reduction, Mn(IV) oxide reduction, and growth on poised electrodes. A real-time, high-throughput Fe(III) citrate reduction assay is described that can screen numerous G. sulfurreducens strain constructs simultaneously and shows the sensitivity of imcH expression by the vanillate system. These tools will enable more sophisticated genetic studies in G. sulfurreducens without polar insertion effects or need for multiple antibiotics.
Detection of Agents That Alter the Bacterial Cell Surface

Abstract Proteus mirabilis is not killed by polymyxin B, normal serum, or sodium deoxycholate. Exposure to polymyxin B renders the cells susceptible to killing by the latter two agents. The data suggest that this synergism is due to polymyxin B-induced surface changes. The results point out an inadequacy of existing methods of screening for antibiotics; they fail to detect agents which, while showing no in vitro effect on growth, may alter a resistant organism so that it becomes more susceptible to other antimicrobials or host defense mechanisms. A method is described which can be used to detect such cell surface-modifying agents.
Transformation of sensory organs by Mutations of the cut locus of D. melanogaster

The identities of two types of sensory organs in the body wall of Drosophila, namely the external sensory organs and the chordotonal organs, are under genetic control. Embryonic lethal mutations in the cut gene complex transform the external sensory organs into chordotonal organs. The neurons, as well as the support cells forming the external sensory structures, change their morphological and antigenic characteristics to those of chordotonal organs, providing genetic evidence that these two types of sensory organs are homologous. Similar transformations of external sensory organs are observed in adult mosaic flies. Analysis of mosaic larvae and flies suggests that the cut gene function is required either in or near external sensory organs in order for them to acquire their correct identity.
UNIVERSAL LINEAR DENSITY OF STATES FOR TUNNELING INTO THE TWO-DIMENSIONAL ELECTRON GAS IN A MAGNETIC FIELD

A new technique permits high fidelity measurement of the tunneling density of states (TDOS) of the two-dimensional electron gas. The obtained TDOS contains no distortions arising from low 2D in-plane conductivity and includes the contribution from localized tunneling sites. In a perpendicular magnetic field, a pseudogap develops in the TDOS at the Fermi level. Improved sensitivity enables resolution of a linear dependence of the TDOS on energy near the Fermi energy. The slopes of this linear gap are strongly field dependent. The data are suggestive of a new model of the gap at low energies.
Distilling Truth from Emotion

Seeking to overturn various "myths" about mathematicians, Hersh and John-Steiner offer "a native9s guide to the culture of mathematics."
Convexity preserving summability matrices

The main result of this paper gives the necessary and sufficient conditions for the Abel matrices to preserve the convexity of sequences. Also, the higher orders of the Cesaro method are shown to be convexity-preserving matrices.
Studies of thermospheric dynamics with a Fabry–Perot interferometer network: A review

Abstract Advances in Fabry–Perot interferometer (FPI) technology implemented within the past decade have been extensive achieving improvements in sensitivity by one or two orders of magnitude. The measurements of thermospheric winds from such FPI observatories would be extremely valuable for ingestion into Space Weather models for the purpose of forecasting ionospheric variability. However, the current state of FPI networking falls short of its potential for interesting science and significant application. In this paper we review the current state of the global FPI network and explain several new and important science goals.
Walsh spectral analysis for ordinary differential equations. I. Initial value problems

Walsh spectral analysis is applied to ordinary differential equations. It is shown that the method is directly equivalent to trapezoidal integration for first-order differential equations. This is a consequence of the finite-dimensional integration operator being of lower triangular Toeplitz form. The method is applied to equations with discontinuous forcing functions, and the numerical results are shown to be superior to those given by either Fourier spectral analysis or Runge-Kutta methods. >
Classification of Multi-dimensional Streaming Time Series by Weighting Each Classifier's Track Record

Extensive research on time series classification in the last decade has produced fast and accurate algorithms for the single-dimensional case. However, the increasing prevalence of inexpensive sensors has reinforced the need for algorithms to handle multi-dimensional time series. For example, modern smartphones have at least a dozen sensors capable of producing streaming time series, and hospital-based (and increasingly, home-based) medical devices can produce time series streams from more than twenty sensors. The two most common ways to generalize from single to multi-dimensional data are to use all the streams or just the single best stream as determined at training time. However, as we show here, both approaches can be very brittle. Moreover, neither approach exploits the observation that different sensors may be considered "experts" on different classes. In this work, we introduce a novel framework for multi-dimensional time series classification that weights the class prediction from each time series stream. These weights are based not only on each stream's previous track record on the class it is currently predicting, but also on the distance from the unlabeled object. As we demonstrate with extensive experiments on real data, our method is more accurate than current approaches and particularly robust in the face of concept drift or sensor noise.
Importance of events per independent variable in proportional hazards analysis I. Background, goals, and general strategy

Multivariable methods of analysis can yield problematic results if methodological guidelines and mathematical assumptions are ignored. A problem arising from a too-small ratio of events per variable (EPV) can affect the accuracy and precision of regression coefficients and their tests of statistical significance. The problem occurs when a proportional hazards analysis contains too few "failure" events (e.g., deaths) in relation to the number of included independent variables. In the current research, the impact of EPV was assessed for results of proportional hazards analysis done with Monte Carlo simulations in an empirical data set of 673 subjects enrolled in a multicenter trial of coronary artery bypass surgery. The research is presented in two parts: Part I describes the data set and strategy used for the analyses, including the Monte Carlo simulation studies done to determine and compare the impact of various values of EPV in proportional hazards analytical results. Part II compares the output of regression models obtained from the simulations, and discusses the implication of the findings.
Evidence for structural changes in dermatan sulfate and hyaluronic acid with aging.

Three dermatan sulfates (DS18, DS28, and DS35) were isolated from women's skin of ages 19 +/- 2.5, 35 +/- 3.5, 47 +/- 1.7, 60 +/- 0.8, and 75 +/- 5 years. They sequentially precipitated with 18, 28, and 35% ethanol. Their sulfate content was: 23.5, 25.3, and 29.0% (w/w) for DS18 at ages 19-35, 47, and 60 years, respectively; 29.0, 24.0, and 18.8% for DS28; and 18.0, 20.0, and 20.6% for DS35 at ages 19-47, 60, and 75 years, respectively. Both DS18 and DS28 decreased, respectively, from 0.030% (of wet-skin weight) to traces at age 75, and from 0.020 to 0.010% at 60 years. At age 75, DS28 apparently increased by 30%. The DS35 values (traces-0.006%) had no age-related trend. Hyaluronic acid (HA) precipitated with 45% ethanol, was 0.030% of skin-weight at ages 19-47, and decreased to 0.015 and 0.007% at 60 and 75 years, respectively. Its electrophoretic mobility was slower at age 47. In the oldest group, i.r. spectra of HA and DS35 displayed no bands at 1650-1600, 1380, and 1320 cm-1, and a new band at 1560 cm-1. Moreover, ninhydrin-positive material of HA and DS35 increased by 75 and 95%, respectively, and the reducing GlcNAc content of HA decreased. These data showed three chemically different dermatan sulfates (two of which were preponderant) and N-deacetylation of HA and DS35 of the oldest group. After age 47, total DS and HA considerably decreased, DS18 and DS35 were oversulfated, and DS28 became undersulfated with aging.
The role of recombination and RAD52 in mutation of chromosomal DNA transformed into yeast

While transformation is a prominent tool for genetic analysis and genome manipulation in many organisms, transforming DNA has often been found to be unstable relative to established molecules. We determined the potential for transformation-associated mutations in a 360 kb yeast chromosome III composed primarily of unique DNA. Wild-type and rad52 Saccharomyces cerevisiae strains were transformed with either a homologous chromosome III or a diverged chromosome III from S. carlsbergensis. The host strain chromosome III had a conditional centromere allowing it to be lost on galactose medium so that recessive mutations in the transformed chromosome could be identified. Following transformation of a RAD+ strain with the homologous chromosome, there were frequent changes in the incoming chromosome, including large deletions and mutations that do not lead to detectable changes in chromosome size. Based on results with the diverged chromosome, interchromosomal recombinational interactions were the source of many of the changes. Even though rad52 exhibits elevated mitotic mutation rates, the percentage of transformed diverged chromosomes incapable of substituting for the resident chromosome was not increased in rad52 compared to the wild-type strain, indicating that the mutator phenotype does not extend to transforming chromosomal DNA. Based on these results and our previous observation that the incidence of large mutations is reduced during the cloning of mammalian DNA into a rad52 as compared to a RAD+ strain, a rad52 host is well-suited for cloning DNA segments in which gene function must be maintained.
Phylogenetic relatedness of circulating HIV-1C variants in Mochudi, Botswana.

Background Determining patterns of HIV transmission is increasingly important for the most efficient use of modern prevention interventions. HIV phylogeny can provide a better understanding of the mechanisms underlying HIV transmission networks in communities. Methods To reconstruct the structure and dynamics of a local HIV/AIDS epidemic, the phylogenetic relatedness of HIV-1 subtype C env sequences obtained from 785 HIV-infected community residents in the northeastern sector of Mochudi, Botswana, during 2010–2013 was estimated. The genotyping coverage was estimated at 44%. Clusters were defined based on relatedness of HIV-1C env sequences and bootstrap support of splits. Results The overall proportion of clustered HIV-1C env sequences was 19.1% (95% CI 17.5% to 20.8%). The proportion of clustered sequences from Mochudi was significantly higher than the proportion of non-Mochudi sequences that clustered, 27.0% vs. 14.7% (p = 5.8E-12; Fisher exact test). The majority of clustered Mochudi sequences (90.1%; 95% CI 85.1% to 93.6%) were found in the Mochudi-unique clusters. None of the sequences from Mochudi clustered with any of the 1,244 non-Botswana HIV-1C sequences. At least 83 distinct HIV-1C variants, or chains of HIV transmission, in Mochudi were enumerated, and their sequence signatures were reconstructed. Seven of 20 genotyped seroconverters were found in 7 distinct clusters. Conclusions The study provides essential characteristics of the HIV transmission network in a community in Botswana, suggests the importance of high sampling coverage, and highlights the need for broad HIV genotyping to determine the spread of community-unique and community-mixed viral variants circulating in local epidemics. The proposed methodology of cluster analysis enumerates circulating HIV variants and can work well for surveillance of HIV transmission networks. HIV genotyping at the community level can help to optimize and balance HIV prevention strategies in trials and combined intervention packages.
Association of Antipsychotic Use With Hospital Events and Mortality Among Medicare Beneficiaries Residing in Long-Term Care Facilities

Objective: Antipsychotic (AP) utilization has grown significantly in long-term care (LTC) settings. Although a growing literature associates AP use with higher mortality in elderly with dementia, the association of APs with hospital events is unclear. The authors examine prevalence and trends in AP use by Medicare beneficiaries residing in LTC and the association of APs and other drug use variables with hospital events and mortality. Design: Retrospective analysis using sequential multivariate Cox proportional hazards models. Setting: Medicare Current Beneficiary Survey linked to Institutional Drug Administration and Minimum Data Set files. Participants: A total of 2,363 LTC Medicare beneficiaries, 1999–2002. Measurements: Trends in LTC AP use overall and by type and duplicative use; association of AP utilization and two outcomes: hospital events and all-cause mortality. Results: AP use rose markedly from 1999 to 2002 (26.4%–35.9%), predominantly due to increased use of atypical agents. After controlling for sociodemographic and clinical factors, AP use is not related to hospital events (hazard ratio [HR] = 0.98, 95% confidence interval [CI] = 0.82–1.63 p=0.7951). AP use is associated with reduced mortality in unadjusted and intermediate models, but loss of significance in the final model (HR = 0.83, 95% CI=0.69–1.00, p=0.0537) suggests that disease and drug burden factors may confound the AP-mortality relationship. Conclusion: This study provides no evidence of increased hospital events or mortality in LTC residents who use AP medications. Findings contribute to a growing body of evidence that APs, particularly atypical agents, may be associated with reduced mortality in LTC residents.
An Empirical Analysis of Price Discrimination Mechanisms and Retailer Profitability

Abstract Retailers typically engage in some form of price discrimination to increase profitability. In this article, the authors compare the impact on retailer profitability of two price discrimination mechanisms: quantity discounts based on package size (second-degree price discrimination) and store-level pricing or micromarketing (third-degree price discrimination). Whereas the latter has been well addressed in the marketing literature, there is limited empirical research on the use of quantity discounts for price discrimination. Using store-level sales data, the authors estimate a structural demand model, accounting for parameter heterogeneity and price endogeneity. They combine the parameter estimates with a model of retailer pricing to conduct optimal pricing and profitability simulations under several scenarios, ranging from constraining the retailer not to engage in any form of price discrimination to the least restrictive scenario of setting nonlinear price schedules specific to each store. The pr...
A Chemical Genetics Approach Reveals H,K-ATPase-Mediated Membrane Voltage Is Required for Planarian Head Regeneration

Summary Biophysical signaling is required for both embryonic polarity and regenerative outgrowth. Exploiting endogenous ion transport for regenerative therapies will require direct regulation of membrane voltage. Here, we develop a pharmacological method to target ion transporters, uncovering a role for membrane voltage as a key regulator of anterior polarity in regenerating planaria. Utilizing the highly specific inhibitor, SCH-28080, our data reveal that H + ,K + -ATPase-mediated membrane depolarization is essential for anterior gene expression and brain induction. H + ,K + -ATPase-independent manipulation of membrane potential with ivermectin confirms that depolarization drives head formation, even at posterior-facing wounds. Using this chemical genetics approach, we demonstrate that membrane voltage controls head-versus-tail identity during planarian regeneration. Our data suggest well-characterized drugs (already approved for human use) might be exploited to control adult stem cell-driven pattern formation during the regeneration of complex structures.
The rarity of acalculous cholecystitis in a term neonate

This case represents a unique finding in neonates, of which there have been few reported cases. A 14 day old male presents with 10 days of vomiting and a right upper quadrant mass. Multiple imaging was performed, including abdominal ultrasounds, HIDA scan, MRCP, and eventually intra-operative cholangiogram with cholecystectomy. The patient was found to have acalculous cholecystitis and hydropic gallbladder. This case is important because recognition of this diagnosis in the neonatal is imperative due to increased risk of morbidity and mortality. Clinicians need to be aware how to appropriately diagnose and treat this uncommon disease.
Molecular Mechanics Parameters and Conformational Free Energies of Proline-Containing Peptides

A new set of AMBER* parameters for proline-containing peptides is reported based on the results of high level ab initio calculations for a model proline dipeptide, 1. These new parameters correct a number of deficiencies in the previous parameters for proline, and Monte Carlo/stochastic dynamics (MC/SD) free energy simulations for 1 with the new parameter set give a good agreement with experiment for both the degree of internal hydrogen bonding and the population of the cis isomer. The new parameter set is also applied to a conformational study of the sequence Ac-(l)Pro-X-NHMe in CHCl3, where X = Gly, (d/l)Ala, (d/l)Val, (d/l)Ser, and (d/l)Asn(N-Me). β-Turn formation is favored by alternating chirality in our simulations so the d-residues in the “X” position always show higher β-turn populations. The enthalpic preference for β-turns in CHCl3 is also reproduced in our simulations. Calculated absolute enthalpies are lower than those found experimentally, but the simulations do correctly reproduce the trends...