cssi/SciSciGPT-SciSciNet huggingface dataset:
Cryo-EM Structures of a Gonococcal Multidrug Efflux Pump Illuminate a Mechanism of Drug Recognition and Resistance.

ABSTRACT Neisseria gonorrhoeae is an obligate human pathogen and causative agent of the sexually transmitted infection (STI) gonorrhea. The most predominant and clinically important multidrug efflux system in N. gonorrhoeae is the multiple transferrable resistance (Mtr) pump, which mediates resistance to a number of different classes of structurally diverse antimicrobial agents, including clinically used antibiotics (e.g., β-lactams and macrolides), dyes, detergents and host-derived antimicrobials (e.g., cationic antimicrobial peptides and bile salts). Recently, it has been found that gonococci bearing mosaic-like sequences within the mtrD gene can result in amino acid changes that increase the MtrD multidrug efflux pump activity, probably by influencing antimicrobial recognition and/or extrusion to elevate the level of antibiotic resistance. Here, we report drug-bound solution structures of the MtrD multidrug efflux pump carrying a mosaic-like sequence using single-particle cryo-electron microscopy, with the antibiotics bound deeply inside the periplasmic domain of the pump. Through this structural approach coupled with genetic studies, we identify critical amino acids that are important for drug resistance and propose a mechanism for proton translocation. IMPORTANCENeisseria gonorrhoeae has become a highly antimicrobial-resistant Gram-negative pathogen. Multidrug efflux is a major mechanism that N. gonorrhoeae uses to counteract the action of multiple classes of antibiotics. It appears that gonococci bearing mosaic-like sequences within the gene mtrD, encoding the most predominant and clinically important transporter of any gonococcal multidrug efflux pump, significantly elevate drug resistance and enhance transport function. Here, we report cryo-electron microscopy (EM) structures of N. gonorrhoeae MtrD carrying a mosaic-like sequence that allow us to understand the mechanism of drug recognition. Our work will ultimately inform structure-guided drug design for inhibiting these critical multidrug efflux pumps.
Prevalence, Concentration, and Antimicrobial Resistance Profiles of Salmonella Isolated from Florida Poultry Litter

ABSTRACT For over a decade, Salmonella contamination has increasingly led to outbreaks of foodborne illness associated with fresh produce. The use of untreated animal manures, or biological soil amendments of animal origin, to amend agricultural soils holds a risk of contamination from foodborne pathogens, such as Salmonella. This study was conducted to determine the prevalence, concentration, serotypes, and antimicrobial resistance profiles of Salmonella in poultry litter from Florida farms. Litter pH, total Kjeldahl nitrogen, total ammonia nitrogen, total phosphorus (P2O5), total potassium (K2O), moisture content, total solids, total ash, organic matter, and aerobic plate count (APC) were also measured. Litter samples (n = 54) were collected from 18 broiler farms across three seasons (spring, summer, and winter). Salmonella concentrations were enumerated using a most-probable-number (MPN) method, and antimicrobial susceptibility testing was performed. The prevalence of Salmonella in litter samples was 61.1%, with a geometric mean of 0.21 ± 20.7 MPN/g. Across all seasons, Salmonella concentrations were not influenced by the chemical, physical, or microbial properties measured. Recovered Salmonella isolates (n = 290) were grouped into serogroups O:4 (43.1%), O:7 (26.9%), O:8 (11.0%), O:1,3,10,19 (7.9%), and O:9,46 (7.2%). Serotyping Salmonella isolates (n = 47) resulted in 12 serotypes, with the most common being Typhimurium (27.7%), Kentucky (17.0%), Enteritidis (14.9%), and Mbandaka (14.9%). Antimicrobial resistance to tetracycline (29.8%), sulfisoxazole (23.4%), and streptomycin (14.9%) was observed. No isolates were resistant to more than two antimicrobial agents. This study provides valuable information for future risk assessments for the use of poultry litter as an untreated biological soil amendment of animal origin. HIGHLIGHTS
A formation maneuvering controller for multiple non-holonomic robotic vehicles

In this paper, we present a new leader–follower type solution to the translational maneuvering problem for formations of multiple, non-holonomic wheeled mobile robots. The solution is based on the graph that models the coordination among the robots being a spanning tree. Our control law incorporates two types of position errors: individual tracking errors and coordination errors for leader–follower pairs in the spanning tree. The control ensures that the robots globally acquire a given planar formation while the formation as a whole globally tracks a desired trajectory, both with uniformly ultimately bounded errors. The control law is first designed at the kinematic level and then extended to the dynamic level. In the latter, we consider that parametric uncertainty exists in the equations of motion. These uncertainties are accounted for by employing an adaptive control scheme. The main contributions of this work are that the proposed control scheme minimizes the number of control links and global position measurements, and accounts for the uncertain vehicle dynamics. The proposed formation maneuvering controls are demonstrated experimentally and numerically.
PAR1 regulation of CXCL1 expression and neutrophil recruitment to the lung in mice infected with influenza A virus.

Background Protease‐activated receptor 1 (PAR1) is expressed in various immune cells and in the lung. We showed that PAR1 plays a role in Coxsackievirus B3 infection by enhancing toll‐like receptor 3‐dependent interferon‐β expression in cardiac fibroblasts.
Revaluations of Fixed Assets and Future Firm Performance: Evidence from the U.K.

We find, as predicted, that upward revaluations of fixed assets by U.K. firms are significantly positively related to future firm performance. Also, current year revaluations (revaluation balances) are significantly positively related to annual returns (prices), indicating revaluations reflect asset value changes. Relations between revaluations and future performance and prices are weaker for higher debt-to- equity ratio firms, indicating motivation affects how revaluations reflect fundamentals. The relations also are weaker for cross-listed firms. Revaluations after a decline in real estate values and a discretion-reducing accounting proposal are less strongly associated with future performance and returns. Downward revaluations are significantly positively related to returns, but small (large) downward revaluations are insignificantly (significantly negatively) related to future performance.
Creep Cavitation and Fracture Due to a Stress Concentration in 2¼ Cr-l Mo

Long-time creep tests of 2¼ Cr-l Mo specimens containing a circular, central hole are analyzed with regard to their creep cavitation behavior. Experimental results and analytical simulation show broad overall agreement, although there are some unexplained disparities on a smaller scale.
The transformations of aryloxysulfonium cations—II : Origin of para-substituted products and benzoxathians

Abstract 2,6-Dimethylphenol is converted to its p-thiomethoxymethyl derivative on reaction with N,N′-dicyclohexylcarbodiimide and dimethyl sulfoxide in a moderately acidic medium. Similar treatment of ortho-unsubstituted phenols affords small amounts of products containing the 5,6-benzo-1,3-oxathian ring system in addition to the normal products described in the preceding paper.1 Studies designed to elucidate the mechanisms of these transformations are described along with a second oxathian ring synthesis.
T Cell Activation in Six Dimensions

What are T cells doing deep within the recesses of the lymph nodes they inhabit? In his Perspective, von Andrian discusses the findings of several studies that use two-photon and confocal microscopy to illuminate (literally) the private lives of T cells.
Increasing Test Coverage in a VLSI Design Course

VLSI Designers know so little about testing that the large, multi-national corporations frequently higher test experts to advise their designers on test problems. The companies even pay a higher salary to the testing experts than to their VLSI Designers. The author's position is that three lectures in every VLSI Design course should be devoted to test. The first lecture would touch briefly on Test Economics, in order to motivate the students to take an interest in testing problems and costs. This lecture would also include introductory Fault Modeling for stuck-faults, delay-faults (transition and path), bridging faults, MOS Transistor Faults, and IDDQ Faults. Industry uses all of these faults in production testing. The second lecture would cover Fault Simulation, as well as Combinational and Sequential automatic test-pattern generation (ATPG) and the reason for redundancy removal (to avoid masking of testable faults). The focus of this lecture should not be on the various algorithms, but rather on the test generation and fault simulation process. This will train the students in redundancy removal techniques, and teach them how to facilitate test generation by removing testability problems from their designs. The final lecture should be on design for testability (DFT). This would cover Full and Partial Scan, as well as the JTAG 1149 Boundary Scan Standard. Scan is included because a very high percentage of designs will employ some form of scan. In addition, built-in self-testing (BIST) should be introduced in this lecture, but details would be omitted. BIST is important, because industry and leading academics project that BIST may appear in 90% of the chips in 11 years. If additional time is available, I would suggest a fourth lecture on Testability Measures, and how they can be used by the designer, to eliminate test generation problems, predict fault coverages, and accelerate ATPG programs.
Tularemic hepatitis presenting as obstructive jaundice

Abstract A 56-yr-old man was admitted for evaluation of fever, chills, jaundice, and acholic stools. Laboratory studies suggested a cholestatic process. Ultrasonography, computed tomography, and transhepatic cholangiography failed to reveal any abnormalities. Acute infection with Francisella tularensis was confirmed serologically, and a liver biopsy revealed cholestatic hepatitis with focal coagulative necrosis. Recovery was coincident with antibiotic therapy.
Responses of Infants and Children to Complex And Novel Stimulation

Publisher Summary Extensive literature is accumulating in the area of stimulus-selection behaviors. Unfortunately, studies on human infants and children constitute a small fraction of the available research. Among child psychologists who have shown an interest in the topic, a concern with an individual difference variable of “curiosity” appears in several instances to have played a rather predominant role in determining their choices of the kinds of data to gather. In such cases, there has been a relative lack of emphasis on the stimulus variables involved. Even clearer instances of this kind of approach may be found in studies that compare various behaviors of children receiving high and low “curiosity” scores, via peer, teacher, or self-ratings, or through the administration of “tests” of curiosity. The search for such laws relating individual differences in “curiosity” to stimulus selection constitutes a perfectly legitimate scientific enterprise. From the standpoint of motivational theory, however, this approach has tended to be accompanied by certain terminological usages that suggest the operation of special purpose motives.
Attachment, Play, and Authenticity: A Winnicott Primer

Part 1 Preface Part 2 Acknowledgements Chapter 3 Overview Chapter 4 Dialectical Meaning-Making in Infancy Chapter 5 A Good Object Must be Found in Order to be Created Chapter 6 The True Self and False Compliance Chapter 7 We are Essentially Isolates, with the Capacity to be Alone Chapter 8 Using Objects and the Capacity to Hate Chapter 9 Integrating Theory with Therapy: The Case of Bob Chapter 10 The Meaning and Power of Play Chapter 11 The Mind, the Body, and the World of Transitional Phenomena Chapter 12 Hate in the Countertransference Chapter 13 The Antisocial Tendency Chapter 14 The Aims of Psychoanalytic Treatment Chapter 15 Winnicott as Therapist More than Theorist Part 16 Bibliography
Invariant object recognition via surface reconstruction neural networks

Classifying objects that are distorted by similarity transform and detection/occlusion noise is a difficult pattern recognition task. The authors present a novel and robust neural network solution based on detected surface boundary points. The method operates in two stages. The object is first parametrically represented by a surface reconstruction neural network (SRNN) trained by the boundary points sampled from the exemplar object. When later presented with distorted object without point correspondence, this parametric representation reduces the effects caused by detection/occlusion and also allows the mismatch information back-propagated through the SRNN to iteratively determine the best similarity transform of the distorted object. The distance measure can then be computed in the reconstructed representation domains between the exemplar object and the aligned distorted object. >
Biologically-Inspired Design of Autonomous and Adaptive Grid Services

This paper describes and evaluates a biologically- inspired network architecture that allows grid services to autonomously adapt to dynamic environment changes in the network. Based on the observation that the immune system has elegantly achieved autonomous adaptation, the proposed mechanism, the iNet artificial immune system, is designed after the mechanisms behind how the immune system detects antigens (e.g., viruses) and specifically reacts to them. iNet models a set of environment conditions (e.g., network traffic and resource availability) as an antigen and a behavior of grid services (e.g., migration and replication) as an antibody. iNet allows each grid service to autonomously sense its surrounding environment conditions (an antigen) to evaluate whether it adapts well to the sensed conditions, and if it does not, adaptively perform a behavior (an antibody) suitable for the sensed conditions. Simulation results show that iNet allows grid services to autonomously adapt their population and location to environmental changes for improving their performance (e.g., response time and throughput) and balancing workload.
Twenty-five-year survivorship of two thousand consecutive primary Charnley total hip replacements: factors affecting survivorship of acetabular and femoral components.

Background: Charnley total hip arthroplasty has been demonstrated to provide good clinical results and a high rate of implant survivorship for twenty years and longer. Most long-term series are not large enough to stratify the many demographic factors that influence implant survivorship. The purpose of this study was to analyze the effects of demographic factors and diagnoses on the long-term survivorship of the acetabular and femoral components used in Charnley total hip arthroplasty. Methods: Two thousand primary Charnley total hip arthroplasties (1689 patients) were performed at one institution from 1969 to 1971. Patients were contacted at five-year intervals after the arthroplasty. Twenty-five years after the surgery, 1228 patients had died and 461 patients were living. Hips that had not had a reoperation, revision or removal of a component for any reason, or revision or removal for aseptic loosening were considered to have survived. Survivorship data were calculated with use of the method of Kaplan and Meier. Patients were stratified by age, gender, and underlying diagnosis to determine the influence of these factors on implant survivorship. Results: The twenty-five year rates of survivorship free of reoperation, free of revision or removal of the implant for any reason, and free of revision or removal for aseptic loosening were 77.5%, 80.9% and 86.5%, respectively. The twenty-five-year survivorship free of revision for aseptic loosening was poorer for each decade earlier in life at which the procedure was performed; this survivorship ranged from 68.7% for patients who were less than forty years of age to 100% for patients who were eighty years of age or older. Men had a twofold higher rate of revision for aseptic loosening than did women. Conclusions: Age, gender, and underlying diagnosis all affected the likelihood of long-term survivorship of the acetabular and femoral components used in Charnley total hip arthroplasty.
Novel Role of Vitamin K in Preventing Oxidative Injury to Developing Oligodendrocytes and Neurons

Oxidative stress is believed to be the cause of cell death in multiple disorders of the brain, including perinatal hypoxia/ischemia. Glutamate, cystine deprivation, homocysteic acid, and the glutathione synthesis inhibitor buthionine sulfoximine all cause oxidative injury to immature neurons and oligodendrocytes by depleting intracellular glutathione. Although vitamin K is not a classical antioxidant, we report here the novel finding that vitamin K1 and K2 (menaquinone-4) potently inhibit glutathione depletion-mediated oxidative cell death in primary cultures of oligodendrocyte precursors and immature fetal cortical neurons with EC50 values of 30 nm and 2 nm, respectively. The mechanism by which vitamin K blocks oxidative injury is independent of its only known biological function as a cofactor for γ-glutamylcarboxylase, an enzyme responsible for posttranslational modification of specific proteins. Neither oligodendrocytes nor neurons possess significant vitamin K-dependent carboxylase or epoxidase activity. Furthermore, the vitamin K antagonists warfarin and dicoumarol and the direct carboxylase inhibitor 2-chloro-vitamin K1 have no effect on the protective function of vitamin K against oxidative injury. Vitamin K does not prevent the depletion of intracellular glutathione caused by cystine deprivation but completely blocks free radical accumulation and cell death. The protective and potent efficacy of this naturally occurring vitamin, with no established clinical side effects, suggests a potential therapeutic application in preventing oxidative damage to undifferentiated oligodendrocytes in perinatal hypoxic/ischemic brain injury.
Multilevel Selection and the Structure of Highly Alienated Groups

This commentary relates the kind of coercive social structure described by Hundeide (2003) to multilevel selection theory, a general evolutionary framework for thinking about social organizations.
Cascaded collector current formulations of abrupt heterojunction bipolar transistors and their applications to graded HBTs with base dopant outdiffusion

Abstract A cascaded thermionic emission-diffusion current model is presented to analyze the forward and inverted collector current in graded HBTs with base dopant outdiffusion. In addition to a reduction of forward IC in HBTs with dopant diffusion, a bias dependent non-ideality factor of IC is also predicted by the cascaded model. Furthermore, the variation of non-ideality factor observed in HBTs with different amounts of dopant outdiffusion can be explained by the formation of a potential barrier and the dominance of thermionic emission current. Based on the inverted collector current formulation, the ratio of currents measured at two heterojunction biases is proposed as an indicator of the integrity of a graded heterojunction. This is based on the fact that when base dopants diffuse into the graded layer, a potential barrier is formed in the conduction band, whose height can be modulated by heterojunction applied reverse bias, resulting in a bias dependent current. As the base dopant outdiffusion affects collector current uniformity across the wafer and device long term reliability, the design of emitter-base heterojunctions is discussed in the context of aluminum composition and grading length.
Comparison of red pigment-concentrating hormones from the eyestalks of the fiddler crab, Uca pugilator, and the prawn, Palaemonetes vulgaris, with synthetic red pigment-concentrating hormone of Pandalus borealis.

Abstract Synthetic Pandalus red pigment-concentrating hormone and extracts of eyestalks from Uca pugilator and Palaemonetes vulgaris were passed through a column of Bio-Gel P-6. In each instance the elution volume of the fraction that provided maximal concentration of the red chromatophoric pigment of Palaemonetes was the same, indicating thereby that these three red pigment-concentrating hormones have either the same or nearly the same molecular size.
The Characterization of Elastic Moduli and Damping Capacities of Graphite/Epoxy Composite Laminated Beams in Hygrothermal Environments

The extensive utilization of polymeric composite materials in commercial applications has mandated that the dynamic response characteristics of these advanced materials be carefully studied under hygrothermal service conditions in order that viable design guidelines be distilled for practicing engineers. Significant progress has been made in understanding both the dynamic response characteristics of polymeric composite materials under iso-hygrothermal conditions and also their static mechanical response characteristics in hygrothermal environments. However, these two areas have generally been treated by the research community as distinct disciplines, and there is a significant void in the literature on evaluating the hygrothermoelastodynamic response of polymeric composite materials. This paper partially addresses this void by presenting a coherent combination of theoretical and experimental investigations on studying the dynamic elastic moduli and damping capacities of composite laminated beams fabricate...
Improved properties of blends of ultrasonically treated unfilled polyurethane rubber

The aim of this investigation is to improve the properties of the polyurethane rubber that has been devulcanized using the coaxial ultrasonic reactor. After devulcanization of the cured rubber under varying gap sizes and amplitudes, blends of the devulcanized and virgin rubber at different ratios are prepared. Rheological and mechanical properties, hardness as well as gel fraction and crosslink density of the vulcanized blends have been investigated. Results show that compared to the vulcanizates of the devulcanized samples, the vulcanizates of the blends show a remarkable improvement in properties, which are sometimes comparable to or even better than the virgin vulcanizate. Blends have also prepared using different proportions of ground samples and virgin rubber, and a comparison of properties between these blends and the blends of the devulcanized rubber has been carried out. The results show that compared to the ground samples, the blends of the devulcanized samples are easier to mix and exhibit enhanced and more uniform properties. Polym. Eng. Sci. 44:794–804, 2004. © 2004 Society of Plastics Engineers.
Caffeine effects on cholesterol and development of aortic and coronary atherosclerosis in rabbits.

Abstract Three epidemiological studies have not revealed any relationship between coffee consumption and the development of ischemic heart disease. One longitudinal study of ischemic heart disease implied that this relationship did exist. Others have shown in several long-term animal experiments with caffeine administration that no hypercholesterolemia-enhancing effect of caffeine exists. Short-term clinical trials in healthy individuals and patients with liver disease who received caffeine both intravenously and orally produced no changes in the cholesterol levels. Previously reported animal experiments have not resulted in severer degrees of atherosclerosis or more extensive involvement of the aortas in caffeine-treated animals compared to control animals. This report clearly demonstrates no increase in coronary atherosclerosis in caffeine-treated animals.
In vitro stimulation of thyroid ornithine decarboxylase activity and polyamines by thyrotropin.

Thyrotropin (TSH) stimulation of ornithine decarboxylase (ODC) activity and polyamine levels was studied in vitro in rat thyroids. The elevation in ODC activity was related to the concentration of TSH in the incubation medium with peak activity at a concentration of 25 mU/ml. ODC activity with 50 mU/ml of TSH was 3 to 5-fold higher than control activity at 5 h of incubation; this stimulation was enhanced by the addition of 0.5 mM 3-isobutyl-l-methyl xanthine (MIX), a phosphodiesterase inhibitor. Dibutyryl cyclic AMP (DbcAMP) also stimulated ODC activity with a dose response up to 2.0 mM. The increase in ODC activity with TSH and MIX was prevented by incubation with actinomycin D (10 μg/ml) or puromycin (0.2 HIM). Putrescine concentrations in rat thyroids rose to three times basal levels after 6 h of incubation with TSH and MIX; no significant elevation in spermidine or spermine was observed after up to 7 h incubation. The increase in tissue putrescine preceded a rise in [3H]uridine incorporation into acid...
In vitro metabolism of etrimfos by rat and mouse liver

Abstract The in vitro metabolism of etrimfos, O,O-dimethyl-O-(2-ethyl-4-ethoxy-6-pyrimidinyl) phosphorothionate, was studied in rat and mouse liver. The major route of metabolism in rat and mouse liver was via glutathione transferase, and the predominant metabolite was desmethyl etrimfos. The higher toxicity of etrimfos to mice was attributed mainly to lower amounts of reduced glutathione in mouse liver. Thus, the level of reduced glutathione appears to be in part responsible for the selective toxicity. No oxygen analog of etrimfos was found.
Gap junctions and tissue business: problems and strategies for developing specific functional reagents

SUMMARY The complex and overlapping tissue distribution of different members of the gap junctional connexin protein family is reviewed. Intermixing of different connexins in the building of intercellular channels and translational and posttranslational regulation of gap junctional channels add additional challenges to the interpretation of the possible functions played by gap junction-mediated intercellular communication in tissue business.
Effects of mental relaxation and slow breathing in essential hypertension

Summary Objectives To compare mental relaxation and slow breathing as adjunctive treatment in patients of essential hypertension by observing their effects on blood pressure and other autonomic parameters like heart rate, respiratory rate, peripheral skin temperature, electromyographic activity of the frontalis muscle and skin conductance. Methods One hundred patients of essential hypertension either receiving antihypertensive drugs or unmedicated were selected randomly. Various parameters were recorded during the resting state and then during mental relaxation and slow breathing for 10min each, separated by a quiet period of 15min. All parameters were recorded again after mental relaxation and slow breathing. Changes in various parameters observed after mental relaxation and slow breathing were analyzed and compared. Results Both mental relaxation and slow breathing resulted in a fall in systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate and electromyographic activity with increase in peripheral skin temperature and skin conductance. Slow breathing caused a significantly higher fall in heart rate ( p p p p p p p >0.2) observed with both the modalities. Conclusions Even a single session of mental relaxation or slow breathing can result in a temporary fall in blood pressure. Both the modalities increase the parasympathetic tone but have effects of different intensity on different autonomic parameters.
Constitutive Modeling of Material Damage for Fatigue Failure Prediction

This paper presents a constitutive modeling of material damage capable of characterizing fatigue damage and plastic damage for rate-independent materials under multiaxial loading with the theory of damage mechanics. First, an internal state variable known as the damage variable is introduced with two scalars to characterize material degradation due to the change of material microstructures under fatigue. Then, depending upon the level of applied stress in a material element, the damage accumulation is postulated to undergo two processes, the accumulation of fatigue damage and plastic damage. Two surfaces, fatigue damage surface and plastic damage surface, are proposed to quantify fatigue damage initiation and plastic damage initiation. The damage-coupled constitutive equations of elasticity and plasticity plus two corresponding damage evolution equations are formulated based on the irreversible thermodynamics. Finally, a failure criterion based on the overall damage accumulation is postulated to govern cr...
Clinician Mindfulness and Patient Safety

PATIENT SAFETY HAS BEEN A TOPIC OF CONSIDERABLE interest over the last decade, with evidence showing that medical errors are responsible for substantial morbidity and mortality. There has been significant progress in understanding, identifying, and addressing errors at a system level; however, the performance of individual clinicians remains a crucial and largely unaddressed element of patient safety. Individual performance is important in diagnostic errors, but these errors are difficult to measure and have received little systematic study. Diagnostic errors often stem from cognitive biases, also referred to as “cognitive dispositions to respond” (CDRs). Because CDRs are integral to human cognition, they are challenging to overcome. Croskerry has delineated more than 30 CDRs and has proposed “debiasing strategies” to prevent errors due to CDRs. Prominent among these strategies is metacognition, or an individual’s knowledge of his or her own thinking process. Notably, there is significant overlap between metacognition and mindfulness, nonjudgmental awareness of the present moment. Increased mindfulness leads to greater awareness and understanding of a person’s experiences, including thoughts, emotions, and bodily sensations. Because education can increase mindfulness, mindfulness instruction for clinicians holds promise as a debiasing strategy for reducing diagnostic and other medical errors.
On Newton's method under mild differentiability conditions and applications

In this study we are concerned with the problem of approximating a locally unique solution of a nonlinear operator equation in a Banach space. We examine the convergence of the Newton-Kantorovich method by assuming that the Frechet-derivative of the nonlinear operator involved is only Holder continuous. Many results exist already in the literature to cover the stronger case when the operator is Lipschitz continuous. Moreover we use this study to counter some claims made by Galperin and Waksman on related work of ours. Furthermore we use our results to solve a two point boundary value problem appearing in kinetic theory of gasses, elasticity and other applied areas.
Anatomic and functional characteristics of the rat ileal pouch.

Abstract Background: The definitive operation for chronic ulcerative colitis (UC) and familial adenomatous polyposis is total proctocolectomy with ileal pouch-anal anastomosis (IPAA). Mild inflammation (pouchitis) is omnipresent in pouches and becomes severe in 50% of UC patients with IPAA. The etiology of pouchitis is likely due to combined genetic, microbial, and immunologic factors. Epithelial cell exposure to surgical trauma and/or to changes in intestinal bacterial composition may account for the inflammatory infiltrate. Progress in understanding pouchitis is restricted by the lack of suitable animal models. Methods: An ileal pouch-rectal anastomosis [IPRA] in rats was developed to reproduce a model of human IPAA and clinical, gross and histologic criteria were determined. Results: Many shared features with human ileal pouch were observed. Conclusion: IPRA is an important in vivo model to study mechanisms of repair, defense and immunity that may contribute to pouchitis.
Reconciling two models of multihierarchical markup

For documents with complex or atypical annotations, multihierarchical structures play the role of the document tree in traditional XML documents. We define a model of overlapping or multihierarchical markup that has both a graph-based and a text-and-tags representation. Our model, which we call the range GODDAG, augments the classical GODDAG (generalized ordered-descendant DAG) structure with order relations over the nodes, and additional constraints that ensure documents have a convenient serialization in terms of tagged text. We provide two alternative constructions for this new model, and prove that documents in the model have (1) a unique representation as a graph, and (2) a straightforward textual representation that satisfies two conditions previously identified as important for serialization. Furthermore, we show how the range GODDAG provides a convenient way to characterize the update operations that may be performed on a document while maintaining serializability.
Ambiguous genitalia: diagnosis, evaluation, and treatment.

The pediatric radiologist plays a significant role in the evaluation and the treatment of infants with ambiguous genitalia. On the first day of life, an investigation should be initiated that includes studies, in particular a sonogram, to demonstrate the presence or absence of a uterus, and a genitogram to define the presence of a vagina. Once gender assignment has been made, information regarding the size of the vagina and its position in regard to the urogenital sinus becomes essential to the pediatric urologist when planning a course for reconstruction. Herein we break down intersex states into four major categories: female pseudohermaphroditism, male pseudohermaphroditism without mullerian structures, and male hermaphroditism with mullerian structures and true hermaphroditism. The role of the radiologist in each of these states is discussed.
Cloning and characterization of a glutamate transporter cDNA from human cerebellum.

The glutamate/aspartate transporters are essential for the elimination and recycling of synaptic glutamate released from nerve endings during neurotransmission. Evidence suggests that these processes are altered in ischemia and neuronal degenerations linked to excitotoxicity. We screened a cDNA library constructed from human cerebellar mRNA, and isolated a cDNA that shows an 88.5% and a 98.7% sequence similarity at the nucleotide and amino acid level, respectively, with a rat brain specific Na+-dependent glutamate/aspartate transporter. The human cDNA is expressed in brain and it may prove useful in the study of human neurodegenerations linked to glutamate dysfunction.
Endovascular Balloon-Assisted Embolization of High-Flow Peripheral Vascular Lesions Using Dual-Lumen Coaxial Balloon Microcatheter and Onyx: Initial Experience

Balloon-assisted embolization performed by delivering Onyx ethylene vinyl alcohol copolymer through a dual-lumen coaxial balloon microcatheter is a new technique for the management of peripheral vascular lesions. This technique does not require an initial reflux of Onyx to form around the tip of the microcatheter before antegrade flow of Onyx can commence. In a series of four patients who were treated with the use of this technique, the absence of significant reflux of Onyx was noted, as were excellent navigability and easy retrieval of the balloon microcatheter. However, in one patient, there was inadvertent adverse embolization of a digital artery, which was not caused by reflux of Onyx but could still be related to balloon inflation.
A Practical Workflow for Making Anatomical Atlases for Biological Research

The anatomical atlas has been at the intersection of science and art for centuries. These atlases are essential to biological research, but high-quality atlases are often scarce. Recent advances in imaging technology have made high-quality 3D atlases possible. However, until now there has been a lack of practical workflows using standard tools to generate atlases from images of biological samples. With certain adaptations, CG artists' workflow and tools, traditionally used in the film industry, are practical for building high-quality biological atlases. Researchers have developed a workflow for generating a 3D anatomical atlas using accessible artists' tools. They used this workflow to build a mouse limb atlas for studying the musculoskeletal system's development. This research aims to raise the awareness of using artists' tools in scientific research and promote interdisciplinary collaborations between artists and scientists. This video (http://youtu.be/g61C-nia9ms) demonstrates a workflow for creating an anatomical atlas.
Do 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline data support the conclusion of threshold carcinogenic effects?

The objectives of this paper are to (1) reexamine the data that were used to support the conclusion of a threshold effect for 2-amino-3,8-dimethylimidazo[4,5-f] quinoxaline (MeIQx)-induced initiation and carcinogenicity at low doses in the rat liver, and (2) discuss issues and uncertainties about assessing cancer risk at low doses. Our analysis is part of an effort to understand proper interpretation and modeling of data related to cancer mechanisms and is not an effort to develop a risk assessment for this compound. The data reanalysis presented herein shows that the low-dose initiation activity of MeIQx, which can be found in cooked meat, cannot be dismissed. It is argued that the threshold effect for carcinogenic agents cannot be determined by statistical non-significance alone; more relevant biological information is required. A biologically motivated procedure is proposed for data analyses. The concept and procedure that are appropriate for analyzing MeIQx data are equally applicable to other compounds with comparable data.
Fate of manuscripts declined by the Journal of the American Academy of Dermatology.

Background Submissions to the Journal of the American Academy of Dermatology (JAAD) undergo a rigorous peer-review process. However, little is known regarding the fate of manuscripts declined by the JAAD. Objective We sought to: (1) determine the proportion of manuscripts declined by the JAAD that are subsequently published elsewhere; (2) identify the journals in which they were published; and (3) study whether the authors of declined manuscripts adopted in their final publications the changes suggested by the JAAD reviewers. Methods We reviewed the outcomes of the 489 submissions declined by the JAAD during two 4-month periods: from March 1, 2004, to June 30, 2004, and from March 1, 2005, to June 30, 2005. Results Of the 981 manuscripts submitted to JAAD during the two 4-month periods studied, 489 manuscripts (50%) were declined. Among the declined manuscripts, 201 (41%) had been subsequently published in other medical journals as of March 1, 2007. Among the 55 journals that published manuscripts declined by JAAD, 23 (42%) were nondermatology journals. The median impact factor for these 55 journals was 1.638, compared with the JAAD's impact factor of 2.402. Among the declined manuscripts, Case Reports comprised the largest proportion (n = 149, 31%), followed by Original Research Reports (n = 90, 18%). Overall, 46 (51%) rejected Original Research Reports were subsequently published, compared with 145 (36%) rejected submissions in other categories that were later published ( P P = .0305). Limitations It is possible that the average lag time of 28 months in this study is not sufficient for some rejected manuscripts to reach subsequent publication. Conclusions Approximately half of the manuscripts rejected by the JAAD were subsequently published in other journals within 28 months, among which, roughly 40% went to nondermatology journals. The median impact factor of the journals that published JAAD-rejected manuscripts was lower than that of the JAAD. Rejected Original Research Reports have a significantly higher probability of being subsequently published than other category submissions. This may be a result of relative quality of Original Research Reports versus submissions for other sections of the journal (eg, Case Reports). Manuscripts that adopted JAAD-reviewer suggestions were subsequently published in journals with higher impact factors than those that did not incorporate JAAD-reviewer suggestions. This indicates that peer-reviewer comments can be useful and important for improving the quality of scientific publications.
Use of Three-Dimensional Basement Membrane Cultures to Model Oncogene-Induced Changes in Mammary Epithelial Morphogenesis

The development of breast carcinomas involves a complex set of phenotypic alterations in breast epithelial cells and the surrounding microenvironment. While traditional transformation assays provide models for investigating certain aspects of the cellular processes associated with tumor initiation and progression, they do not model alterations in tissue architecture that are critically involved in tumor development. In this review, we provide examples of how three-dimensional (3D) cell culture models can be utilized to dissect the pathways involved in the development of mammary epithelial structures and to elucidate the mechanisms responsible for oncogene-induced phenotypic alterations in epithelial behavior and architecture. Many normal mammary epithelial cell lines undergo a stereotypic morphogenetic process when grown in the presence of exogenous matrix proteins. This 3D morphogenesis culminates in the formation of well-organized, polarized spheroids, and/or tubules that are highly reminiscent of normal glandular architecture. In contrast, transformed cell lines isolated from mammary tumors exhibit significant deviations from normal epithelial behavior in 3D culture. We describe the use of 3D models as a method for both reconstructing and deconstructing the cell biological and biochemical events involved in mammary neoplasia.
Transient Response of Floating Ring Liquid Seals

The design and analysis of pressure balanced seals are important to the designers and users of turbomachinery which require floating element seals. The design objective for compressor seals differs from that of the engineered pump seal but the common factor includes the ability to predict the dynamic response of the floating ring seal relative to the rotor shaft. Steady-state calculations can be used to study possible operating conditions for compressor designs, but they do not include accurate account of rotor shaft response and ring spin torque. In addition, engineered pump seal applications are such that the ring is expected to track shaft movement during start-up and shut-down transients when reduced pressures and leakage produce laminar flow sealing conditions. The analysis presented in this paper gives the designer the ability to evaluate seal ring dynamic transient response, including friction stick-slip on the axial sealing face and the ring spin torque interaction with the antirotation element. The analysis results presented in this paper were obtained from a personal computer program written specifically for seal transient analysis.
Factors associated with sterilization use among women leaving a U.S. jail: a mixed methods study

Background Despite the high rates of reported sterilization use among women who have spent time in correctional facilities, little is known about the context in which women in this population choose this option. The objective of our study was to use both quantitative and qualitative methods to understand factors associated with sterilization use among women leaving a U.S. jail.
Heritability of Hyperphagic Eating Behavior and Appetite-Related Hormones among Hispanic Children

FISHER, JENNIFER O., GUOWEN CAI, SANDRA J. JARAMILLO, SHELLY A. COLE, ANTHONY G. COMUZZIE, AND NANCY F. BUTTE. Heritability of hyperphagic eating behavior and appetite-related hormones among Hispanic children. Obesity. 2007;15:1484–1495. Objective: Eating in the absence of hunger (EAH) may be a genetically influenced phenotype of overweight children, but evidence is limited. This research evaluated the heritability (h 2 ) of EAH and its association with overweight among Hispanic children 5 to 18 years old. Genetic and environmental associations of EAH with overweight, fat mass, and key hormonal regulators of food intake were also evaluated. Research Methods and Procedures: A family design was used to study 801 children from 300 Hispanic families. Weighed food intakes were used to measure EAH after an ad libitum dinner providing 50% of estimated energy needs. Fasting ghrelin, amylin, insulin, and leptin were measured by immunoassays. Measured heights, weights, and fat mass (using DXA) were obtained. Total energy expenditure (TEE) was measured by room respiration calorimetry. Results: On average, children consumed 41% of TEE at the dinner meal, followed by an additional 19% of TEE in the absence of hunger. Overweight children consumed 6.5% more energy at dinner (p 0.001) and 14% more energy in the absence of hunger (p 0.001) than non-overweight children. Significant heritabilities were seen for EAH (h 2 0.51) and dinner intake (h 2 0.52) and for fasting levels of ghrelin (h 2 0.67), amylin (h 2 0.37), insulin (h 2 0.37), and leptin (h 2 0.34). Genetic correlations were seen between eating behavior and fasting hormones, suggesting common underlying genes affecting their expression. Discussion: This research provides new evidence that overweight Hispanic children exhibit elevated levels of hyperphagic eating behaviors that are influenced by genetic endowment.
Sex Combs are Important for Male Mating Success in Drosophila melanogaster

The sex comb is one of the most rapidly evolving male-specific traits in Drosophila, making it an attractive model to study sexual selection and developmental evolution. Drosophila males use their sex combs to grasp the females' abdomen and genitalia and to spread their wings prior to copulation. To test the role of this structure in male mating success in Drosophila melanogaster, we genetically ablated the sex comb by expressing the female-specific isoform of the sex determination gene transformer in the tarsal segments of male legs. This technique does not remove the sex comb entirely, but simply restores the morphology of its constituent bristles to the ancestral condition found in Drosophila species that lack sex combs. Direct observations and differences in long-term insemination rates show that the loss of the sex comb strongly reduces the ability of males to copulate with females. Detailed analysis of video recordings indicates that this effect is not due to changes in the males' courtship behavior. Rapid evolution of sex comb morphology may be driven either by changes in female preferences, or by co-evolution between sex combs and female external genitalia.