cssi/SciSciGPT-SciSciNet huggingface dataset:
‘Harmful Cultural Practices’ and AIDS

In this chapter I show how ‘harmful cultural practices’ have emerged as a development issue in global conventions and policies over the past ten years starting with current policies and mapping backwards to the first step taken by the UN in 2001 at the United Nations General Assembly Special Session on HIV/AIDS. In the second section I look at the shift from the global to the national level and demonstrate how international policies have influenced national policy on AIDS and harmful cultural practices in Malawi. I use data collected from interviews and documents to show how the Malawian elite have constructed narratives around AIDS and cultural practices in Malawi; that rural people’s backwardness is to blame for high HIV prevalence rates.
Effect of Salt on the Ordinary–Extraordinary Transition in Solutions of Charged Macromolecules

Using dynamic light scattering technique, we address the role of added salt at higher concentrations on the "ordinary-extraordinary" transition in solutions of charged macromolecules. The "ordinary" behavior has previously been associated with a "fast" diffusion coefficient which is independent of salt concentration Cs and polymer concentration Cp if the ratio Cp/ Cs is above a threshold value. The "extraordinary" transition is associated with formation of aggregates, with a "slow" diffusion coefficient, formed from similarly charged macromolecules. By investigating aqueous solutions of sodium poly(styrenesulfonate) and sodium chloride with variations in Cp, Cs, and polymer molecular weight, Mw, we report the emergence of a new diffusive "fast" relaxation mode at higher values of Cp, Cs, and Mw, in addition to the previously known "fast" and "slow" relaxation modes. Furthermore, we find that Mw plays a crucial role on the collective dynamics of polyelectrolyte solutions with salt, instead of just the Cp/ Cs ratio as previously postulated. As Mw is progressively decreased, the salty solution exhibits dynamical transitions from three modes to two modes and then to one mode of relaxation. The emergence of the new fast mode and the dynamical transitions are in marked departure from the general premise of the ordinary-extraordinary transition developed over several decades. In an effort to rationalize our experimental findings we present a theory for the collective dynamics of polyelectrolyte solutions with salt by addressing the coupling between the relaxations of polyelectrolyte chains, counterions from the polymer and added salt, and co-ions from the salt. The predictions are in qualitative agreement with experimental findings. The present combined work of experiments and theory forms the basis for accurately characterizing dynamics of charged macromolecules in salty solutions, which are ubiquitous in biological systems and polyelectrolyte-based technologies.
Theoretical design of coupled high contrast grating (CHCG) waveguides to enhance CO 2 light-absorption for gas sensing applications

In this work, we present a theoretical study on using high contrast grating (HCG) designs to enhance light–gas interaction in the mid-infrared range. The optical behavior of a single layer HCG was studied under the presence of CO 2 gas. Through optimizing the structure parameters, we could confine an intense electric field over the grating layer. Consequently, about 200 times of light-absorption enhancement was observed. To further improve the performance, a coupled HCG (CHCG) was proposed to introduce another vertical photonic confinement mechanism. We found that CHCG can restrict much intense light energy in the structure leading to over 600 times of light-absorption enhancement. However, it is noticed that a significant part of the concentrated electric field was still trapped in the high index areas, where the gas cannot interact. To address this issue, a modified CHCG with a thin substrate thickness was proposed. Through the optimization ( T = 1.149 μ m), we were able to redistribute most of the light energy into the void space of the CHCG layer which resulted in close to 1400 times of improvement. This work clearly demonstrates that using HCG for enhancing light–gas interaction is a promising approach to make on-chip gas sensing devices. Furthermore, it can also be integrated into other photonic components, e.g., fibers for advanced sensing system development.
Spectral Clustering for Customer Phase Identification Using AMI Voltage Timeseries

Smart grid technologies and wide-spread installation of advanced metering infrastructure (AMI) equipment present new opportunities for the use of machine learning algorithms paired with big data to improve distribution system models. Accurate models are critical in the continuing integration of distributed energy resources (DER) into the power grid, however the low-voltage models often contain significant errors. This paper proposes a novel spectral clustering approach for validating and correcting customer electrical phase labels in existing utility models using the voltage timeseries produced by AMI equipment. Spectral clustering is used in conjunction with a sliding window ensemble to improve the accuracy and scalability of the algorithm for large datasets. The proposed algorithm is tested using real data to validate or correct over 99% of customer phase labels within the primary feeder under consideration. This is over a 94% reduction in error given the 9% of customers predicted to have incorrect phase labels.
Laparoscopic entry techniques: What is the controversy?

Objective To review reported complications related to the different laparoscopic entry techniques in the human and veterinary literature and describe the benefits and limitations of each technique. Study design Literature review of 57 peer-reviewed articles. Methods An electronic database search identified human and veterinary literature describing complications related to entry technique during laparoscopy. Results Open- and closed-entry techniques may result in trauma of abdominal organs or vasculature. During laparoscopy in man, injury to bowel and major vasculature is reported in 0.02% and 0.04% of procedures with open- or closed-entry techniques, respectively. Designs of Veress needles and trocar cannula assemblies have been developed to improve ease and safety. Early complications, defined as those observed at the time of port entry into the abdominal cavity, result from the puncture of a blood vessel leading to substantial visible hemorrhage. Late complications are detected 24 or 48 hours after surgery and result from the puncture of a loop of intestine that was not detected at the time of initial surgery. The major reasons for iatrogenic trauma in man are related to anatomical factors and the presence of adhesions. No explanation for cause of complications was identified for animals. Conclusion There is no consensus in the human or veterinary literature about the best entry technique for laparoscopy. The rate of complications related to entry technique in small animals is not known because the data are underreported. Clinical significance Complications related to entry techniques are expected in both man and animals. Improvements in techniques and equipment design are being developed to minimize risk.
Anorectal Manometry in Wistar Rats with Inexpensive Setup: A Physiological Description of the Mechanical Activity

Anorectal manometry is a common technique for investigating the performance of the anal canal. The absence of the rectosphincteric reflex may determine the existence of important pathologies. Animal models are essential to assess the efficacy of new therapies as well as to provide a better understanding of the physiological mechanisms underlying intestinal motility. This paper describes an inexpensive laboratory setup for experimental anorectal manometry that consists of a water-perfused customized catheter, a signal acquisition and processing system, and a personal computer with a software program to display biosignals. Twenty Wistar rats, ten males and ten females, were anesthetized using a ketamine–xylazine intraperitoneal injection. The basal tone of the anorectal sphincter and the rectosphincteric reflex were studied. In basal conditions, two frequency peaks were found, one at 0.015 ± 0.007 Hz and the other at 0.363 ± 0.057 Hz, corresponding to slow and ultraslow pressure waves, respectively. The maximum resting pressure varied between 37.8 and 109.0 mmHg. Anorectal relaxations derived from stimulation of the rectum wall dropped to 82.65 ± 14.61 % of the pressure level prior to stimulation. The overall period of the relaxation wave was 10.22 ± 2.91 s. Differences between genders were found: autonomous pressure oscillations were significantly slower in female rats whereas the period of the relaxation wave was significantly shorter in male subjects. Overall, the mechanical description of the anal canal in Wistar rats is similar to that in humans, especially to that in newborns. Therefore, it represents a good animal model for the investigation of anorectal motility.
Does Affirmative Action Incentivize Schooling? Evidence from India

Abstract Affirmative action raises the likelihood of getting into college or obtaining a government job for minority social groups in India. I find that minority group students are incentivized to ...
Opioid-limiting legislation associated with decreased 30-day opioid utilization following anterior cervical decompression and fusion.

Abstract BACKGROUND CONTEXT Since 2016, 35 of 50 US states have passed opioid-limiting laws. The impact on postoperative opioid prescribing and secondary outcomes following anterior cervical discectomy and fusion (ACDF) remains unknown. PURPOSE To evaluate the effect of opioid-limiting regulations on postoperative opioid prescriptions, emergency department (ED) visits, unplanned readmissions, and reoperations following elective ACDF. STUDY DESIGN/SETTING Retrospective review of prospectively-collected data. PATIENT SAMPLE Two hundred and eleven patients (101 pre-law, 110 post-law) undergoing primary elective 1–3 level ACDF during specified pre-law (December 1st, 2015–June 30th, 2016) and post-law (June 1st, 2017–December 31st, 2017) study periods were evaluated. METHODS Demographic, medical, surgical, clinical, and pharmacological data was collected from all patients. Total morphine milligram equivalents (MMEs) filled was compared at 30-day postoperative intervals, before and after stratification by preoperative opioid-tolerance. Thirty- and 90-day ED visit, readmission, and reoperation rates were calculated. Independent predictors of increased 30-day and chronic (>90 day) opioid utilization were evaluated. RESULTS Demographic, medical, and surgical factors were similar pre-law versus post-law (all p>.05). Post-law, ACDF patients received fewer opioids in their first postoperative prescription (26.65 vs. 62.08 pills, p 90 day) opioid requirements were associated with preoperative opioid exposure (odds ratio 4.42, p .05). Pre- and post-law patients were similar in terms of 30- or 90-day ED visits, unplanned readmissions, and reoperations (all p>.05). CONCLUSIONS Implementation of mandatory opioid prescribing limits effectively decreased 30-day postoperative opioid utilization following ACDF without a rebound increase in prescription refills, ED visits, unplanned hospital readmissions, or reoperations for pain.
Algorithms Using Previous Resistance, Prior Antimicrobial Prescriptions, and Patient Place of Residence Enhance Empirical Therapy for Women With Uncomplicated Urinary Tract Infections

ABSTRACT Objective To evaluate how previous antimicrobial resistance, prior prescription data and patient place of residence (ZIP code) can guide empiric therapy for uncomplicated urinary tract infections (UTI). Guidelines recommend empiric antimicrobial selection for women with symptoms of uncomplicated UTIs, most commonly trimethoprim-sulfamethoxazole (SXT), nitrofurantoin (NIT) or ciprofloxacin (CIP). Previous antimicrobial resistance and prior prescription data are potential predictors of resistance in subsequent urine cultures for UTIs. Also, there is evidence of geographic clustering of antimicrobial resistance for UTIs. Methods Retrospective data from women (age ≥ 18) with an assigned diagnosis of UTI, submitting urine cultures as outpatients (2011-2018), were gathered. Univariate analyses and multivariable regression models were used to determine odds ratios (OR) for predicting resistance to SXT, NIT and CIP on the 2011-2017 data. Antimicrobial choice algorithms were created using 2011-2017 results and tested on 2018 data. Results In the training cohort, 9,455 women had diagnoses of uncomplicated UTIs and positive urine cultures. Prevalence of resistance for SXT, NIT and CIP was 19.4%, 12.1% and 10.3%, respectively. A urine culture with previous resistance, prior antimicrobial prescription within two years and ZIP code were the strongest predictors of a subsequent resistant culture. An algorithm based on these data had a success rate of 92.2%, compared to provider's choice (87.5%, p Conclusions Previous resistance, prior prescriptions and patient ZIP code are predictors of subsequent resistance in patients with uncomplicated UTIs. Algorithms using these data can outperform real-world outcomes and guidelines.
Si-based materials for lithium-ion batteries V. n-SiO powder

X-ray photoelectron spectroscopy was used to analyze Si powders that have a native oxide surface, obtained from Paraclete Energy, Inc. The spectra were obtained using incident monochromatic Al Kα radiation at 1486.6 eV (0.834 01 nm). An initial survey spectrum together with O 1s, C 1s, and Si 2p are presented. A final survey spectrum was collected to ascertain the amount of beam-induced damage, which appears to be minimal. The spectra indicate the principal core level photoelectron and Auger electron signals with only minor nitrogen signal and show the expected oxidized carbon and silicon species related to atmospheric exposure.
The road to academic surgical leadership: Characteristics and experiences of surgical chairpersons.

Abstract Background The evolving landscape of academic surgery demands leaders who are not only effective clinicians and researchers, but also administrators able to navigate complex hospital organizations, financial pressures in the era of quality measures, and inclusion of an increasingly diverse workforce. The aim of this study was to characterize achievements and assess perspectives in becoming a surgical chair in order to guide young surgeons in their career trajectories to surgical leadership. Methods A survey encompassing demographics, surgical training, nonmedical advanced degrees, academic advancement, and leadership experiences was sent via electronic mail to members of the American College of Surgeons Society of Surgical Chairs in December 2018. Results Of 191 Society of Surgical Chairs members, 52 (27.2%) completed the survey, with 6 (11.5%) women, 40 (76.9%) white, and the majority becoming chair between ages 46 and 60 (n = 39, 75.0%). Training beyond residency included fellowships (n = 41, 78.8%) and advanced nonmedical degrees (n = 15, 28.8%). Median H-index was 47 (range 10–120) with 126 (5–500) research publications, and grants received was 2 (0–38) for federal and 5 (0–43) for industry. Female chairs appear to have fewer nonmedical degrees (n = 1) and no difference in age at becoming chair (66.7% vs 79.6% between ages 46 and 60), H-index (26 [10–41] vs 49 [17–120]), or publications (93 [10–189] vs 150 [5,500]). Prior educational (n = 36, 69.2%) and clinical (n = 44, 84.6%) leadership roles were common, with 30 chairs (57.7%) having held both roles. Experiences which respondents felt have most helped them function as chair included serving as a clinical division director (n = 37, 71.2%), residency program director (n = 28, 53.8%), leadership courses (n = 28, 53.8%), a research career (n = 22, 42.3%), and being a vice/interim chair (n = 15, 28.8%). Personal traits felt to be most important in becoming a successful chair included being effective at communication (n = 37, 71.2%), collaborative (n = 35, 67.3%), trustworthy (n = 30, 57.7%), and a problem-solver (n = 27, 51.9%). Conclusion Becoming a department surgical chair often involves not only surgical subspecialty expertise, but also nonmedical training and prior leadership roles, which help facilitate development of skills integral to navigating the collaborative and diverse nature of academic surgery in the current era.
Pervasive data access in wireless and mobile computing environments: Research Articles

The rapid advance of wireless and portable computing technology has brought a lot of research interests and momentum to the area of mobile computing. One of the research focus is on pervasive data access. With wireless connections, users can access information at any place at any time. However, various constraints such as limited client capability, limited bandwidth, weak connectivity, and client mobility impose many challenging technical issues. In the past years, tremendous research efforts have been put forth to address the issues related to pervasive data access. A number of interesting research results were reported in the literature. This survey paper reviews important works in two important dimensions of pervasive data access: data broadcast and client caching. In addition, data access techniques aiming at various application requirements (such as time, location, semantics and reliability) are covered. Copyright © 2006 John Wiley & Sons, Ltd.
A Self-Mixing Receiver for Wireless Frequency Synchronization in Coherent Distributed Arrays

A self-mixing receiver support distributed frequency locking in coherent distributed antenna arrays is presented. Coherent distributed antenna arrays require accurate phase, frequency, and time alignment. However, each node in the distributed array generates its frequency using independent oscillators, and thus without appropriate frequency synchronization the emitted signals will not appropriately cohere. In this paper, we present a one-way frequency transfer approach that uses a self-mixing circuit architecture in a master-slave synchronization architecture. The master node transmits a multi-tone signal that consists of two tones separated by a 10 MHz frequency reference. The self-mixing circuit receives and demodulates this signal by splitting it and then passing it to the radio-frequency (RF) and local oscillator (LO) terminals of a mixer. The resulting signal is filtered to retain only the 10 MHz modulation, which is used to discipline the oscillator on the slave node. We present experimental results using software-defined radio, showing wireless synchronization via a cabled distributed beamforming experiment at 1.5 GHz.
A Fast and Flexible Algorithm for Solving the Lasso in Large-scale and Ultrahigh-dimensional Problems

Abstract Since its first proposal in statistics (Tibshirani, 1996), the lasso has been an effective method for simultaneous variable selection and estimation. A number of packages have been developed to solve the lasso efficiently. However as large datasets become more prevalent, many algorithms are constrained by efficiency or memory bounds. In this paper, we propose a meta algorithm batch screening iterative lasso (BASIL) that can take advantage of any existing lasso solver and build a scalable lasso solution for large datasets. We also introduce snpnet, an R package that implements the proposed algorithm on top of glmnet (Friedman et al., 2010a) for large-scale single nucleotide polymorphism (SNP) datasets that are widely studied in genetics. We demonstrate results on a large genotype-phenotype dataset from the UK Biobank, where we achieve state-of-the-art heritability estimation on quantitative and qualitative traits including height, body mass index, asthma and high cholesterol.
Estimating the Effect of Crime Risk on Property Values and Time on Market: Evidence from Megan's Law in Virginia

We examine neighborhood externalities that arise from the perceived risk associated with the proximity of a registered sex offender's residence. We find large negative externality effects on a property's price and liquidity, employing empirical techniques that include a fixed-effects OLS model, a correction for sample selection bias and censoring using a Heckman treatment, and a three-stage least-squares model to account for simultaneity bias in the joint determination of a home's sale price and liquidity. Additionally, we find amplified effects for homes with more bedrooms (a proxy for children) and if the nearby offender is designated by the state as “violent.”
Book review essay: The Budapest School: Beyond Marxism:

J.F. Dorahy's The Budapest School: Beyond Marxism (2019) offers contemporary readers a conscientious assessment of the intellectual initiatives of Agnes Heller, Gyorgy Markus, and Ferenc Feher, bot...
Phase Transition on DLA

We have carried out the first exact enumeration approach to multifractal spectra of DLA, using methods similar to Nagatani renormalization group. Specifically, we form the partition function Z(β,L) = ∑α C α ∑ i p i,α α , where Cα is the weight of configuration α, p i,α is growth probability of site i of configuration α, and L is the length scale of clusters. The “free energy” of the system is calculated from L-F(β,L) = Z(β,L), the “energy” from E(β,L) = ∂F(β,L)/∂β, and the “specific heat” from C(β,L) = ∂E(β,L)/∂β,
Climate model biases in seasonality of continental water storage revealed by satellite gravimetry

[1] Satellite gravimetric observations of monthly changes in continental water storage are compared with outputs from five climate models. All models qualitatively reproduce the global pattern of annual storage amplitude, and the seasonal cycle of global average storage is reproduced well, consistent with earlier studies. However, global average agreements mask systematic model biases in low latitudes. Seasonal extrema of low-latitude, hemispheric storage generally occur too early in the models, and model-specific errors in amplitude of the low-latitude annual variations are substantial. These errors are potentially explicable in terms of neglected or suboptimally parameterized water stores in the land models and precipitation biases in the climate models.
Zebrafish: from hematology to hydrology.

Summary. Hemostasis is a defense mechanism that protects an organism from bleeding. Abnormal hemostasis results in bleeding disorders and thrombosis. Several factors are known to control hemostasis in mammals. Despite this progress, more factors remain to be identified. Classical genetic approaches have resolved physiological pathways. However, classical genetics could not be applied completely to hemostasis pathways a decade ago. We introduced zebrafish as a model system to study hemostasis and thrombosis using classical genetic methods. First, we established that zebrafish hemostasis is essentially similar to mammalian hemostasis. Secondly, we developed screening tools for isolating hemostatic mutants. These tools enabled us to identify hemostatic mutants, as well as providing a means to study hemostasis by knockdown methods. Continued characterization of the physiology of thrombus formation led to the novel finding of thrombocyte clustering. Recently, we have discovered that fish secrete proteases, which participate in hemostasis and may have direct relevance in humans. Future work to identify most of the players in thrombus formation is underway.
Hierarchical inference of disparity

Disparity selective cells in V1 respond to the correlated receptive fields of the left and right retinae, which do not necessarily correspond to the same object in the 3D scene, i.e., these cells respond equally to both false and correct stereo matches. On the other hand, neurons in the extrastriate visual area V2 show much stronger responses to correct visual matches [Bakin et al, 2000]. This indicates that a part of the stereo correspondence problem is solved during disparity processing in these two areas. However, the mechanisms employed by the brain to accomplish this task are not yet understood. Existing computational models are mostly based on cooperative computations in V1 [Marr and Poggio 1976, Read and Cumming 2007], without exploiting the potential benefits of the hierarchical structure between V1 and V2. Here we propose a two-layer graphical model for disparity estimation from stereo. The lower layer matches the linear responses of neurons with Gabor receptive fields across images. Nodes in the upper layer infer a sparse code of the disparity map and act as priors that help disambiguate false from correct matches. When learned on natural disparity maps, the receptive fields of the sparse code converge to oriented depth edges, which is consistent with the electrophysiological studies in macaque [von der Heydt et al, 2000]. Moreover, when such a code is used for depth inference in our two layer model, the resulting disparity map for the Tsukuba stereo pair [middlebury database] has 40% less false matches than the solution given by the first layer. Our model offers a demonstration of the hierarchical disparity computation, leading to testable predictions about V1-V2 interactions.
Measuring the Potential for Victimization in Malicious Content

Sending malicious content to users for obtaining personnel, financial, or intellectual property has become a multi-billion dollar criminal enterprise. This content is primarily presented in the form of emails, social media posts, and phishing websites. User training initiatives seek to minimize the impact of malicious content through improved vigilance. Training works best when tailored to specific user deficiencies. However, tailoring training requires understanding how malicious content victimizes users. In this paper, we link a set of malicious content design factors, in the form of degradations and sophistications, to their potential to form a victimization prediction metric. The design factors examined are developed from an analysis of over 100 pieces of content from email, social media and websites. We conducted an experiment using a sample of the content and a game-based simulation platform to evaluate the efficacy of our victimization prediction metric. The experimental results and their analysis are presented as part of the evaluation.
Glass Curtain Wall Elements:Properties and Behavior

The spate of recent failures of glass claddings in modern high-rise buildings has called attention to the need for improved understanding of cladding static and dynamic behavior so that rational procedures for its design can be developed. To this end, a frame-panel finite element model was developed to represent a typical portion of the glass curtain wall between story levels in a 29-story glass-clad building and a parametric study of its displacement response and vibration properties was conducted. Window response was shown to be sensitive to the rotational stiffness of the gasket and flexural stiffness of the framing elements for selected panel aspect ratios. Vibration frequencies of the frame-window system were in good agreement with values obtained in field and laboratory experiments. The cladding model presented is suitable for inclusion in existing multistory building models and is currently being used to study cladding-structure interaction in high-rise buildings.
A Secure Protocol for Ubiquitous Sensing and Monitoring of Patient Conditions

Wireless sensor devices are envisioned to collect long term medical data that aid medical professionals in the care and treatment of the elderly and other patients with chronic diseases. Using wearable body sensor networks (BSNs), patients may live more mobile and independent lives than they would in a hospital, nursing home, or rehabilitation center. As a result, the quality of life can be improved and the cost for medical care can be reduced. Although security issues in BSNs have been studied previously, most existing work focuses on monitoring patients in a fixed location such as a hospital and nursing home, relying on centralized approaches that often have poor scalability. In this paper, we develop a new protocol to support secure and scalable anytime/anywhere monitoring of patients to give them full mobility, support the security of sensitive medical data, and preserve the location privacy of patients, while sharing sensor data collection and retrieval workloads among distributed storage nodes.
Mode of infection, nodulation specificity, and indigenous plasmids of 11 fast-growing Rhizobium japonicum strains.

Abstract Eleven fast-growing strains of Rhizobium japonicum were characterized with respect to indigenous plasmids and abilities to infect (Inf+) and nodulate (Nod+) cowpea, siratro, wild soybean, and three commercial cultivars of soybean. All strains caused infection via infection threads in root hairs and consistently nodulated cowpea, siratro, and wild soybean in growth pouches. Interactions with commercial cultivars of soybean were strikingly strain specific. Some combinations were Nod-, and infection was delayed in others. The ratios of infections to nodules and the distribution of nodules on primary and lateral roots also varied substantially. A modified in-gel lysis procedure was devised for electrophoretic separation of plasmids from the strains. Plasmids (ranging in size from 35 to greater than 300 megadaltons) were reproducibly detected in all strains.
σ Factor and Anti-σ Factor That Control Swarming Motility and Biofilm Formation in Pseudomonas aeruginosa

ABSTRACT Pseudomonas aeruginosa is capable of causing a variety of acute and chronic infections. Here, we provide evidence that sbrR (PA2895), a gene previously identified as required during chronic P. aeruginosa respiratory infection, encodes an anti-σ factor that inhibits the activity of its cognate extracytoplasmic-function σ factor, SbrI (PA2896). Bacterial two-hybrid analysis identified an N-terminal region of SbrR that interacts directly with SbrI and that was sufficient for inhibition of SbrI-dependent gene expression. We show that SbrI associates with RNA polymerase in vivo and identify the SbrIR regulon. In cells lacking SbrR, the SbrI-dependent expression of muiA was found to inhibit swarming motility and promote biofilm formation. Our findings reveal SbrR and SbrI as a novel set of regulators of swarming motility and biofilm formation in P. aeruginosa that mediate their effects through muiA, a gene not previously known to influence surface-associated behaviors in this organism. IMPORTANCE This study characterizes a σ factor/anti-σ factor system that reciprocally regulates the surface-associated behaviors of swarming motility and biofilm formation in the opportunistic pathogen Pseudomonas aeruginosa. We present evidence that SbrR is an anti-σ factor specific for its cognate σ factor, SbrI, and identify the SbrIR regulon in P. aeruginosa. We find that cells lacking SbrR are severely defective in swarming motility and exhibit enhanced biofilm formation. Moreover, we identify muiA (PA1494) as the SbrI-dependent gene responsible for mediating these effects. SbrIR have been implicated in virulence and in responding to antimicrobial and cell envelope stress. SbrIR may therefore represent a stress response system that influences the surface behaviors of P. aeruginosa during infection.
Dynamics of a modified Leslie–Gower model with double Allee effects

Bifurcation analysis of a class of modified Leslie–Gower model with Allee effects in both predator and prey species is given in detail. We show the existence of a heteroclinic separatrix that divides the dynamics of the predator and prey populations and considers the Hopf bifurcation around the interior positive equilibrium. We show that when there are two interior equilibria, the smaller equilibrium is always a saddle, and the larger equilibrium can be either an attractor or a repeller surrounded by a limit cycle. Combining mathematical analysis and numerical simulation, we show that the double Allee effects greatly alter the outcome of the survival of both species.
Verification of a designed intramolecular hydrogen bond in a drug scaffold by nuclear magnetic resonance spectroscopy.

2D 1H−15N HMBC NMR acquired at natural abundance and DMSO titration monitored by 1D 1H NMR verified the existence of an intramolecular hydrogen bond that was designed to mimic the pyrimidinone ring of a class of kinase inhibitors. A scalar coupling across the hydrogen bond was detected in organic and aqueous solvent, suggesting a simple and general approach for testing the propensity of intramolecular hydrogen bonds to stabilize pseudo-rings in drug scaffolds.
Degradation of Pulp-Mill Effluent by Oxygen and Na5[PV2Mo10O40], a Multipurpose Delignification and Wet Air Oxidation Catalyst

Water-soluble salts of polyoxometalate (POM) anions can be used as (net) catalysts for selective, effluent-free oxygen delignification (bleaching) of unbleached kraft wood-pulps. Essential to this process is the use of the POM anions as catalysts for the wet oxidation of the lignin removed from the pulp fibers. In anaerobic bleaching, a 0.5 M solution of {alpha}-Na{sub 5}[PV{sub 2}Mo{sub 10}O{sub 40}] (POM{sub ox}) is combined with wood pulp and the mixture heated to 125 C. This treatment dissolves certain organic compounds (some lignin and polysaccharide fragments) with a combined chemical oxygen demand (COD) of 1,500--2,000 mg of O{sub 2}L. Before the solution can be used again for bleaching, the POM anions (POM{sub red}) must be reoxidized and the dissolved organic compounds removed. Here, a second function of the POM anions is realized. They are used under mild conditions (150 C, 0.7 MPa of O{sub 2}) to catalyze the wet air oxidation of the dissolved organic compounds. After several cycles of anaerobic bleaching and wet oxidation, a steady-state condition in COD (at ca. 550 mg of O{sub 2}/L) is achieved.
Effect of Poly(ethylene glycol)s on Micellar Stability of Sodium Dodecyl Sulfate

The effects of poly(ethylene glycol)s of different molecular weights on the micellar stability of sodium dodecyl sulfate in the concentration range from 50 to 600 mM were investigated. The presence of polymer was found to decrease micellar stability drastically. The decreased stability of micelles is explained by the increased population of small aggregates in the presence of polymer. This decreases the value of “resistance” for the micellar formation−dissolution process. The foaming property of SDS solutions in the presence of poly(ethylene glycol) was related to micellar stability.
759Temporal tuning in the acquisition of cognitive skill

Thetemporal tuning hypothesis suggests that individuals adjust the timing of cognitive performances to achieve temporal coordination of mental processes and the data on which they operate, and that this adjustment becomes more precise with practice. Participants in two experiments performed self-paced multiple-step arithmetic tasks in which the information needed for each step was briefly displayed at the participants’ request. Timing constraints were manipulated by varying between subjects the delay between requests and displays of information. In Experiment 1, both operators and operands appeared step by step, and participants achieved a modest degree of temporal adjustment that did not change with practice. In Experiment 2, participants could preview operators while operands appeared step by step. In that experiment, participants achieved more precise temporal adjustment, and the amount of adjustment increased with practice. These results demonstrate the phenomenon of temporal tuning in symbolic cognitive skills and suggest some constraints on the ability to anticipate the time course of one’s mental processes.
Statistical significance analysis of nuclear magnetic resonance-based metabonomics data

Use of nuclear magnetic resonance (NMR)-based metabonomics to search for human disease biomarkers is becoming increasingly common. For many researchers, the ultimate goal is translation from biomarker discovery to clinical application. Studies typically involve investigators from diverse educational and training backgrounds, including physicians, academic researchers, and clinical staff. In evaluating potential biomarkers, clinicians routinely use statistical significance testing language, whereas academicians typically use multivariate statistical analysis techniques that do not perform statistical significance evaluation. In this article, we outline an approach to integrate statistical significance testing with conventional principal components analysis data representation. A decision tree algorithm is introduced to select and apply appropriate statistical tests to loadings plot data, which are then heat map color-coded according to P score, enabling direct visual assessment of statistical significance. A multiple comparisons correction must be applied to determine P scores from which reliable inferences can be made. Knowledge of means and standard deviations of statistically significant buckets enabled computation of effect sizes and study sizes for a given statistical power. Methods were demonstrated using data from a previous study. Integrated metabonomics data assessment methodology should facilitate translation of NMR-based metabonomics discovery of human disease biomarkers to clinical use.
Isolation and characterization of a protochordate histocompatibility locus

Histocompatibility—the ability of an organism to distinguish its own cells and tissue from those of another—is a universal phenomenon in the Metazoa. In vertebrates, histocompatibility is a function of the immune system controlled by a highly polymorphic major histocompatibility complex (MHC), which encodes proteins that target foreign molecules for immune cell recognition. The association of the MHC and immune function suggests an evolutionary relationship between metazoan histocompatibility and the origins of vertebrate immunity. However, the MHC of vertebrates is the only functionally characterized histocompatibility system; the mechanisms underlying this process in non-vertebrates are unknown. A primitive chordate, the ascidian Botryllus schlosseri, also undergoes a histocompatibility reaction controlled by a highly polymorphic locus. Here we describe the isolation of a candidate gene encoding an immunoglobulin superfamily member that, by itself, predicts the outcome of histocompatibility reactions. This is the first non-vertebrate histocompatibility gene described, and may provide insights into the evolution of vertebrate adaptive immunity. The rejection of transplanted tissues is a puzzling phenomenon; it can be explained as a necessary evil of immune system function, but it could also be an evolutionary relic or a real function that we do not understand. The discovery of the first known non-vertebrate histocompatibility locus suggests that there is some truth in at least two of these suggestions. Colonies of the colonial sea-squirt Botryllus schlosseri that make contact either reject each other or undergo a natural transplantation reaction to produce a chimaera, depending on which version of a polymorphic gene called FuHC is present. It is the product of this gene that has now been found to be a member of the immunoglobulin family, similar to the major histocompatibility complex that encodes the proteins that target foreign molecules for immune cell recognition in vertebrates.
Studies on the isolation and substructure of mammalian neurofilaments.

Intact neurofilaments were isolated from minced segments of desheathed rat peripheral nerve by subjecting tissues to osmotic shock in media containing chelating agents and sedimenting heavier tissue components by centrifugation. Isolated neurofilaments were layered on carbon—Formvar-coated grids, fixed by flotation on 5% formalin, and visualized by negative staining with unbuffered uranyl acetate. Neurofilaments comprised the predominant constituent organelle of these preparations. Individual neurofilaments coursed as discrete unbranching linear structures for distances of at least 10 μm. Fresh or fixed neurofilaments appeared as compact cylindrical structures 80–110 A in diameter; lateral sidearm projections were not evident. Exposure to 0.5 M urea prior to fixation altered neurofilaments and exposed substructural configurations. Urea-treated preparations revealed the presence of 20- to 25-A protofilaments. Pairs of protofilaments appeared to be arranged in helical configurations as evidenced by profiles with herringbone substructural patterns. Accordingly, mammalian neurofilaments appear to closely resemble similar organelles of invertebrate species.
Tocolytic treatment for the management of preterm labor: A review of the evidence

Abstract Objective: Preterm labor is often a prelude to early births and the significant attendant burden of infant morbidity and mortality. Treatment consists of bedrest, hydration, pharmacologic interventions, and combinations of these. We systematically reviewed the effectiveness of tocolytics to stop uterine contractions (first-line therapy) or maintain quiescence (maintenance therapy). Our objective was to evaluate the evidence on the benefits and harms of five classes of tocolytic therapy for treating uterine contractions related to preterm labor—β-mimetics, calcium channel blockers, magnesium, nonsteroidal anti-inflammatory agents, and ethanol. Study Design: Reports of randomized controlled trials and other study designs in English, French, and German identified from searches of MEDLINE, EMBASE, specialized databases, bibliographies of review articles, unpublished literature, and discussions with investigators in the field were identified. Studies on women with preterm labor between 1966 and February 1999 that met our inclusion criteria were included. Through dual review, we abstracted the following information: study design and masking; definitions of preterm labor and successful tocolysis; patient inclusion/exclusion characteristics; patient demographic characteristics; drug and cointerventions; and numerous birth, maternal, and neonatal outcome measures. Results: Of the 256 articles evaluated, we abstracted data from 60 first-line and 15 maintenance studies. Of these, 16 first-line and 8 maintenance studies met more stringent requirements for meta-analyses. Studies of first-line tocolysis (grade Fair) reveal a mixed outcome pattern with small improvement in pregnancy prolongation and birth at term relative to placebo. Data were insufficient to show directly a beneficial effect on neonatal morbidity or mortality. Ethanol was less beneficial than, and β-mimetics were not superior to, other tocolytic options. Maintenance tocolytics (grade Poor) showed no improvements in birth or infant outcomes relative to placebo; these results were confirmed through meta-analysis. In contrast to other tocolytic treatments, maternal harms from β-mimetics were rated High; all tocolytics were rated as Low risk for short-term neonatal harms. Conclusions: Management of uterine contractions with first-line tocolytic therapy can prolong gestation. Among the tocolytics, however, β-mimetics appear not to be better than other drugs and pose significant potential harms for mothers; ethanol remains an inappropriate therapy. Continued maintenance tocolytic therapy has little or no value. (Am J Obstet Gynecol 2003;188:1648-59.)
Negotiating with Insurgents: Changing Perceptions or Changing Politics?

Abstract High costs have long been seen as motivating conflict participants to seek peace. This article discusses two types of deviations from the “hurting-stalemate” logic: negotiations in the absence of high costs and non-negotiation in the face of high costs. Two prominent explanations for these deviations are discussed and evaluated, initially through a statistical analysis of peace overtures in intrastate conflicts and then through a case study of the Indian civil war in Kashmir. The results suggest that theoretical explanations focusing on the preferences and political strength of leaders have traction at all levels of violence. Variables associated with shifts in perception, such as leadership change or political shocks, seem to have different effects as the level of violence in a conflict changes.
A comparative study of proteolytic activities in the venoms of some North American snakes.

Abstract 1. 1. Venoms from four species of North American snakes were investigated with respect to their proteolytic activities. All of the venoms readily hydrolyzed protein substrates and certain esters. 2. 2. The esterase and proteinase activities differed in pH optima and in their susceptibility to inhibition by diisopropylphorofluoridate and by phenylmethanesulfonyl fluoride. 3. 3. The venoms possessed no carboxypeptidase or true aminopeptidase activity, but measurable amounts of arylamidase activity were present in all of the venoms. 4. 4. Proteolysis by the venom from Agkistrodon piscivorus piscivorus was inhibited by reducing agents and chelating agents; inhibition by the latter could not be reversed by alterations in pH or magnesium ion concentration. 5. 5. The effects of several divalent ions on proteolysis by the venoms were tested. None of these ions greatly enhanced protein hydrolysis, but several were inhibitory.
Differential expression of the antioxidant response element within the hNQO1 promoter in NSCLC versus SCLC

Abstract To determine whether the human (h) NQO1 (NAD(P)H: quinone oxidoreductase 1) gene contains DNA sequences that directly mediate its high and low expression in non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC), respectively, a series of deletion constructs spanning up to −4 kb of the 5 ′ flanking region of hNQO1 was used in transient transfection assays. The antioxidant response element (ARE) was found to be critical to the elevated expression of NQO1 in NSCLC. However, the ability of both heterologous and deletion promoter constructs to confer ARE responsiveness demonstrated that SCLC contains the necessary program/menu of transcription factors responsible to drive hNQO1 expression via the ARE. By examining the regulatory region of the hNQO1 gene, we identified a proximal repressor region between −259 and −131. These results provide the first evidence of a proximal repressor region exerting a negative role on the regulation of the hNQO1 promoter in SCLC.
Beating-heart mitral valve chordal replacement

Replacing open-heart surgical procedures with beating-heart interventions substantially decreases the trauma and risk of a procedure. One of the most challenging procedures to perform on the beating heart is valve repair. To address this need, this paper proposes a tool for replacing mitral valve chordae to correct regurgitation. The chordae is secured to the papillary muscle and leaflet using NiTi tissue anchors that also incorporate an internal adjustment mechanism to enable initial adjustment as well as subsequent readjustment of chordae length. Efficacy of the proposed tool for chordae replacement and reduction of regurgitation was demonstrated in an ex-vivo heart simulator.
The eclipse of legislatures: Direct democracy in the 21st century

Demographic, political, and technological trends are fueling an unprecedented growth in direct democracy worldwide. If the trends continue, direct democracy threatens to eclipse legislatures in setting the policy agenda. This article reviews existing scientific knowl- edge about the initiative and referendum - the main institutions of direct democracy - and highlights key issues for the future.