cssi/SciSciGPT-SciSciNet huggingface dataset:
Universal Best Arm Identification

In this paper, we study the problem of universal best arm identification in multi-armed bandits, where the underlying setting can be either stochastic or adversarial and is not revealed to the forecaster a priori. We propose an algorithm, called S3-BA, that identifies the best arm without prior knowledge of the underlying setting. The key idea is to simultaneously explore the arms and learn the problem setting, and switch when adversarial is declared. We analyze the performance of the proposed algorithm for both stochastic and adversarial bandits. For stochastic bandit, we prove an upper bound on the error rate of S3-BA. For adversarial bandit, we show that the best arm can be guaranteed as long as the budget is above a threshold. Both results are comparable to the best known algorithms that are specifically designed for the corresponding settings. More importantly, we prove that the “learning loss” due to the formulation uncertainty is negligible compared to the arm selection policies, for both stochastic and adversarial bandits. We also propose an adaptive version of S3-BA, Ad-S3-BA, that facilitates the parameter tuning via a simultaneous gap estimation. Experimental results on both synthetic and real-world datasets corroborate the theoretical analysis of S3-BA, and in particular, demonstrate the performance superiority for the real-world datasets that exhibit a “pseudo-stochastic” behavior.
Targeting the Fn14-Rac1 signaling pathway in invasive glioma cells

1995 Genetic alterations in malignant gliomas affect cell proliferation and cell cycle control, and are currently the targets of most chemotherapeutic agents. However, the efficacy of treating advanced glial tumors with adjuvant therapies remains largely unsuccessful due to the inability to effectively target invading cells. We have been investigating whether the multifunctional cytokine tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and its receptor fibroblast growth factor-inducible 14 (Fn14) regulate glioma cell invasive activity. In a previous report, we demonstrated that Fn14 expression was elevated in glioblastoma multiforme (GBM) specimens and also up-regulated in migrating glioma cells in vitro and invading cells in vivo. Moreover, Fn14-induced glioma invasion is dependent on the small GTPase Rac1. Rac1 is a ubiquitous signaling protein operating in many normal tissues; consequently, therapeutic targeting of this protein would likely have toxic effects on normal cells. It is possible that targeting key regulators of Rac1 may be a more effective and specific therapy toward invading glioma cells. In this study, we found that Ect2, a guanine nucleotide exchange factor (GEF) for Rho family GTPases, including Rac1 and Cdc42, is overexpressed in GBM, and that overexpression of Ect2 correlates directly with tumor grade and inversely with patient survival. Our data shows that Ect2 regulates Rac1 activation downstream of Fn14. Depletion of Ect2 by siRNA duplexes abrogates Fn14-induced Rac1 activation and subsequently glioma cell migration. We also found that TWEAK stimulates the activation of Cdc42 and that this is mediated by Ect2. Interestingly, depletion of Cdc42 expression impairs TWEAK-induced Rac1 activation and also results in a significant reduction of glioma cell migration in vitro. This suggests that Cdc42 is, in part, important for Rac1 activation downstream of the TWEAK-Fn14 signaling pathway and argues for the presence of other Rac-GEF(s) being involved in the Fn14-Rac1 signaling axis. Thus, therapy designed to interfere with the function of specific Fn14 signaling elements is likely to target invasive glioblastoma cells.
Polypyridyl iridium(III) based catalysts for highly chemoselective hydrogenation of aldehydes

Abstract Iridium-catalyzed transfer hydrogenation (TH) of carbonyl compounds using HCOOR (R = H, Na, NH4) as a hydrogen source is a pivotal process as it provides the clean process and is easy to execute. However, the existing highly efficient iridium catalysts work at a narrow pH; thus, does not apply to a wide variety of substrates. Therefore, the development of a new catalyst which works at a broad pH range is essential as it can gain a broader scope of utilization. Here we report highly efficient polypyridyl iridium(III) catalysts, [Ir(tpy)(L)Cl](PF6)2 {where tpy = 2,2′:6′,2′'-Terpyridine, L = phen (1,10-Phenanthroline), Me2phen (4,7-Dimethyl-1,10-phenanthroline), Me4phen (3,4,7,8-Tetramethyl-1,10-phenanthroline), Me2bpy (4,4′-Dimethyl-2–2′-dipyridyl)} for the chemoselective reduction of aldehydes to alcohols in aqueous ethanol and sodium formate as the hydride source. The reaction can be carried out efficiently in broad pH ranges, from pH 6 to 11. These catalysts are air stable, easy to prepare using commercially available starting materials, and are highly applicable for a wide range of substrates, such as electron-rich or deficient (hetero)arenes, halogens, phenols, alkoxy, ketones, esters, carboxylic acids, cyano, and nitro groups. Particularly, acid and hydroxy groups containing aldehydes were reduced successfully in basic and acidic reaction conditions, demonstrating the efficiency of the catalyst in a broad pH range with high conversion rates under microwave irradiation.
Targeting Regorafenib-Induced Toxicity through Inhibition of Gut Microbial β-Glucuronidases

Regorafenib (Stivarga) is an oral small molecule kinase inhibitor used to treat metastatic colorectal cancer, hepatocellular carcinomas, and gastrointestinal stromal tumors. Diarrhea is one of the most frequently observed adverse reactions associated with regorafenib. This toxicity may arise from the reactivation of the inactive regorafenib-glucuronide to regorafenib by gut microbial β-glucuronidase (GUS) enzymes in the gastrointestinal tract. We sought to unravel the molecular basis of regorafenib-glucuronide processing by human intestinal GUS enzymes and to examine the potential inhibition of these enzymes. Using a panel of 31 unique gut microbial GUS enzymes derived from the 279 mapped from the human gut microbiome, we found that only four were capable of regorafenib-glucuronide processing. Using crystal structures as a guide, we pinpointed the molecular features unique to these enzymes that confer regorafenib-glucuronide processing activity. Furthermore, a pilot screen identified the FDA-approved drug raloxifene as an inhibitor of regorafenib reactivation by the GUS proteins discovered. Novel synthetic raloxifene analogs exhibited improved potency in both in vitro and ex vivo studies. Taken together, these data establish that regorafenib reactivation is exclusively catalyzed by gut microbial enzymes and that these enzymes are amenable to targeted inhibition. Our results unravel key molecular details of regorafenib reactivation in the GI tract and provide a potential pathway to improve clinical outcomes with regorafenib.
Bypass and Deconstructive Technique for Hunt and Hess Grade 3-5 Aneurysmal Subarachnoid Hemorrhage Deemed Unfavorable for Endovascular Treatment: Case Series of Outcomes and Comparison with Clipping.

Background Intracranial bypass to treat ruptured aneurysms has been well described in the literature but is largely deferred in patients with higher Hunt and Hess (H & H) grades due to complexity and length of surgery, risk of inducing vasospasm, and poor prognosis. However, there is a paucity of data and no direct comparison with more traditional open surgical techniques. This study investigated outcomes in patients with H & H grade 3–5 aneurysmal subarachnoid hemorrhage (aSAH) unfavorable for stand-alone endovascular treatment managed with bypass compared with direct surgical clipping. Methods A prospective database of patients treated for aSAH with H & H grade 3–5 between 2013 and 2018 was retrospectively analyzed. Complications and functional status at discharge and latest follow-up were compared between patients who underwent bypass surgery versus direct clipping. Results Twenty-three patients underwent revascularization, and 60 underwent clipping alone. There were no significant differences in all-cause 30-day mortality (15% vs. 16%; P = 0.97) or Glasgow Outcome Scale and modified Rankin Scale at discharge or median 8-month follow-up (P > 0.67). There was a higher overall stroke rate with revascularization (P = 0.004), specifically endovascular treatment-related stroke (P = 0.049), with no difference in surgical (P = 0.47) or vasospasm-related stroke (P = 0.53). There were no differences in overall complications, medical complications, seizures, reruptures, hydrocephalus, or perioperative death (P > 0.05). Conclusions Bypass is a viable option for patients presenting with higher H & H grade aSAH deemed unfavorable for stand-alone endovascular therapy. Despite obvious differences in aneurysm complexity and a higher risk of stroke, functional outcomes with revascularization can be comparable with clipping in this high-risk patient cohort.
An Open Standard for Ka-band Interoperable Satellite Antennas

The Ka-band satellite communications market is currently fragmented with each satellite network operator using different frequency bands, polarizations and waveforms. With recent advancements in antenna and RF electronics technology, it is possible to deploy interoperable antennas that are compatible with all Ka-band satellite networks and waveforms. This paper proposes a minimum set of requirements for an inter-operable Ka-band satellite antenna and associated RF electronics
1 Overview of Forensic Psychology

The specialty of forensic psychology can trace its roots to the beginning of the 20th century, when Professor Hugo Munsterberg implored judges and lawyers to seek the assistance of psychologists when wrestling with a variety of issues they were faced with, and psychologists began assessing youth who were involved in legal proceedings in newly established juvenile courts. The landscape of forensic psychology—has changed dramatically in the ensuing century. The American Psychological Association has formally recognized forensic psychology as a specialty, training opportunities are available at all levels (graduate, internship, fellowship, continuing education) for psychologists and aspiring psychologists interested in the area, focused professional organizations and publications are thriving, and practitioners can demonstrate their competence via a certification process offered by the American Board of Forensic Psychology. Munsterberg would be happy to know that, consistent with his hopes, current-day forensic psychologists engage in a variety of pursuits and activities that impact the legal system, including research, teaching, consultation, treatment, and evaluation. It is this latter activity that is the focus of this volume, which provides a contemporary overview of the field. After a review of issues that are relevant to all forensic psychology practice, a variety of civil, criminal, and special forensic evaluation activities are addressed by chapter authors, followed by presentation of a number of chapters devoted to important and challenging non-assessment pursuits. Keywords: forensic; history; Munsterberg; specialty; certification; training; competence
Fragility index of network meta-analysis with application to smoking cessation data.

Abstract Background and Objectives The network meta-analysis (NMA) is frequently used to synthesize evidence for multiple treatment comparisons, but its complexity may affect the robustness (or fragility) of the results. The fragility index (FI) is recently proposed to assess the fragility of the results from clinical studies and from pairwise meta-analyses. We extend the FI to NMAs with binary outcomes. Methods We define the FI for each treatment comparison in NMAs. It quantifies the minimal number of events necessary to be modified for altering the comparison's statistical significance. We introduce an algorithm to derive the FI and visualizations of the process. A worked example of smoking cessation data is used to illustrate the proposed methods. Results Some treatment comparisons had small FIs; their significance (or nonsignificance) could be altered by modifying a few events’ status. They were related to various factors, such as P-values, event counts, and sample sizes, in the original NMA. After modifying event status, treatment ranking measures were also changed to different extents. Conclusion Many NMAs include insufficiently compared treatments, small event counts, or small sample sizes; their results are potentially fragile. The FI offers a useful tool to evaluate treatment comparisons’ robustness and reliability.
Do Monetary Incentives Undermine Performance on Intrinsically Enjoyable Tasks? A Field Test

Economists have long been intrigued by an influential literature in psychology positing that monetary pay lowers performance on enjoyable tasks by crowding out agents' intrinsic interest in them. B...
Iron Deficiency Anemia is Associated with Increased Early Postoperative Surgical and Medical Complications Following Total Hip Arthroplasty.

Abstract Background Iron deficiency anemia (IDA) is a medical comorbidity commonly diagnosed in those undergoing primary total hip arthroplasty (THA). The authors sought to evaluate IDA as a risk factor for early postoperative complications following discharge and describe the hospital resource utilization of this patient population. Methods Patients with a diagnosis of IDA who underwent THA from 2005 to 2014 were identified in a national insurance database. The rates of postoperative medical complications and surgery-related complications, as well as hospital readmission, emergency department visits, and death were calculated. Additionally, 90-day and day of surgery cost and length of stay were calculated. IDA patients were then compared to a 4:1 matched control population without IDA using a logistic regression analysis to control for confounding factors. Results In total, 98,681 patients with a preoperative diagnosis of IDA who underwent THA were identified and compared to 386,724 controls. IDA was associated with increased risk of 30-day emergency department visits (odds ratio [OR] 1.35, P Conclusion Patients with preoperative IDA undergoing THA are at greater risk of experiencing early postoperative complications and have greater utilization of hospital resources.
Experimental and numerical study on heat transfer driven dynamics and control of transient variations in a solar receiver

Abstract A novel and compact variable aperture mechanism coupled to flow channels for recovery of spilled solar power was implemented on a cavity-type solar receiver to regulate its temperature and compensate for the sun’s transient variations. PID and model predictive control methods were initially numerically tested and tuned, and then experimentally tested using a 10 kWe high flux solar simulator for set point tracking and disturbance rejection under simulated sun’s direct normal irradiance. The variable aperture demonstrated a promising performance in regulating the solar receiver’s average temperature by maintaining it within ±1.5 °C of its set point under experimental transient variations. The aperture mechanism’s high performance was achieved while capturing approximately 54% of intercepted spilled solar power, which can be used to preheat the feedstock for better process efficiencies or made available to a secondary end-use process. Additionally, the aperture mechanism was shown to reduce the receiver’s temperature drop in the absence of solar radiation by closing the variable aperture blades which reduced re-radiation losses from the receiver’s cavity. Finally, two other control strategies were experimentally investigated, namely PID feedstock flow rate controller and PID multiple-input single-output controller that can manipulate both the variable aperture size and feedstock flow rate. In all cases and despite severe solar power fluctuations, the variable aperture mechanism demonstrated a promising performance in regulating the temperature in a solar receiver and compensating for the sun’s transient variations.
Observed Sex Differences in Cardiometabolic Indices in Patients on Antipsychotics: Secondary Analyses of a 12-Month Multicenter, Randomized, Controlled Trial.

OBJECTIVE To define sex differences in cardiometabolic indice changes over 12 months in patients on antipsychotics and to describe treatment complexity, interventions, and patient satisfaction of pharmacist comprehensive medication management (CMM) services. METHODS Secondary analyses of time effect-associated sex differences in cardiometabolic indices within and between study groups were done at baseline and 12 months. Each group consisted of 60 subjects who received full pharmacist CMM services (PCS) and 60 subjects who received either modified or no CMM services (NCS). Pharmacist CMM services are a team-based practice of providing direct patient care. RESULTS Significant sex differences in mean change score were observed from baseline to 12 months in the combined PCS and NCS subjects. Compared to men, women had greater body weight (P = .003) and waist measurement (P = .02) reductions and increased serum level of high-density lipoproteins (P < .001). In contrast, men had greater systolic (P < .001) and diastolic (P = .005) blood pressure levels, more hypertension diagnoses (P = .01), and less dyslipidemia diagnoses (P = .001) compared to women at 12 months. Significant sex differences were observed in combined PCS and NCS groups for glycated hemoglobin (HgbA1c) (women: -0.33%, P = .02) and low-density lipoprotein (men: -21.63 mg/dL, P = .04) at 12 months. In PCS women, a significant (P = .02) reduction in mean HgbA1c percentages (-0.46%) compared to PCS men (0.28%) was observed at 12 months. A higher percentage (62%, n = 28/45) of PCS women compared to PCS men (38%, n = 17/45) at 12 months continued to receive CMM services. Satisfaction survey results positively favored CMM services; however, the response rate was only 25% (n = 18/72). CONCLUSIONS Women on antipsychotics appear more likely to keep follow-up visits, return satisfaction surveys, reduce abdominal weight, and improve both HgbA1c percentages and high-density lipid levels compared to men over 12 months. Women were satisfied overall with CMM services. Recognition of sex differences can promote a more personalized patient-centered care approach among patients prescribed antipsychotics. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT02029989.
Platelet adhesion potential estimation in a normal and diseased coronary artery model: effects of shear stress magnitude versus shear stress history

Platelets play a salient role in the pathogenesis of coronary diseases; primarily through their adhesion to other platelets, endothelial cells and plasma proteins. It is necessary for platelets to ...
Juvenile stress increases cocaine-induced impulsivity in female rats.

Abstract In humans, adverse childhood experiences are associated with an increased risk of developing a neuropsychiatric disorder. Changes in social behavior and cognitive function are hallmarks of numerous neuropsychiatric disorders. Here we examined the effects of exposure to variable stress during the juvenile period on social behavior, reward, and cognitive function (as measured in the 5-choice serial reaction time task (5CSRTT)) in rats. From postnatal days (PND) 25–29 male and female rats were exposed to a variable stress protocol. In adulthood, social interactions and sucrose preference were assessed prior to training on the 5CSRTT. Once successfully trained, rats were challenged with different task versions, and then the effects of cocaine (0, 10, or 20 mg/kg, IP) on performance were assessed. A follow-up experiment examined the ability of the D2 receptor antagonist eticlopride (0.0, 0.025, 0.05 mg/kg, IP) to block the effects of cocaine on 5CSRTT performance in female rats. Male rats exposed to juvenile stress tended to engage in less social behavior and had an increased correct response latency in the 5CSRTT following cocaine administration. Female rats exposed to juvenile stress exhibited a trend towards increased social behavior and demonstrated increased cocaine-induced impulsivity. The increase in impulsivity was not blocked by co-administration of eticlopride. Juvenile stress had minimal effects on adult behavior in male rats, but increased cocaine-induced impulsivity in female rats. Such an effect could contribute to the enhanced escalation of drug-use observed in females that experience juvenile stress. This possibility awaits further testing.
Utilization of Distiller's dried grains with solubles: A review

Abstract Ethanol production from various cereal grains faces a growing demand in the global market. Alongside is the increasing production of its co-product, distiller's dried grains with solubles (DDGS), reaching more than 22 million tons in 2019 in the United States. Due to its high nutritional value, the utilization of DDGS as an animal feed additive, fertilizer, and source of corn oil is beneficial to the agricultural industry, as well as improving environmental sustainability. As a relatively new raw material, the technological and economical aspects of its utilization must be explored to achieve more sustainable production and utilization. Other potential utilization of DDGS, including agricultural, medical, industrial, food, and pet food applications could make it more valuable as a renewable resource. This review discusses the nutrient composition, production, and current utilization of DDGS, as well as the challenges and future directions of this industry.
Incorporating Opportunities for Active Learning

This chapter makes the case that because our goal is the facilitation of learning, we should integrate teaching strategies into our presentations that encourage students to actively engage with our content, even if these activities use some portion of our allotted time. Intentional use of questioning is the most familiar and efficient way to facilitate active learning. Other strategies include the use of “workshop” activities, mini-assignments, and branching-plot cases. Healthy presentations require learners to engage in an array of cognitive processes, help learners build upon prior knowledge, and facilitate the retention of content.
Examining social class and multilingualism through the Linguistic Landscape: A methodological proposal

Abstract This article presents a methodological proposal for using the Linguistic Landscape (LL) to examine the intersection of multilingualism and social class in urban settings. The article draws from a study that considered how patterns of linguistic diversity in public signage in a mid-sized US city mapped onto socioeconomic levels. The main innovation for LL methodology is the study’s use of census data and geographic information system (GIS) to increase representativeness using two main constructs (social class and linguistic diversity). After presenting the project design, the challenge of creating representative mapping in the LL is considered, with the solutions the research team generated. Finally, we discuss several practical issues specific to doing LL fieldwork in urban contexts: access, safety, and photography.
Splitting method for solving the coarse-mesh discretized low-order quasi-diffusion equations

In this paper, the development is presented of a splitting method that can efficiently solve coarse-mesh discretized low-order quasi-diffusion (LOQD) equations. The LOQD problem can reproduce exactly the transport scalar flux and current. To solve the LOQD equations efficiently, a splitting method is proposed. The presented method splits the LOQD problem into two parts: (a) the D problem that captures a significant part of the transport solution in the central parts of assemblies and can be reduced to a diffusion-type equation and (b) the Q problem that accounts for the complicated behavior of the transport solution near assembly boundaries. Independent coarse-mesh discretizations are applied: the D problem equations are approximated by means of a finite element method, whereas the Q problem equations are discretized using a finite volume method. Numerical results demonstrate the efficiency of the methodology presented. This methodology can be used to modify existing diffusion codes for full-core calculations (which already solve a version of the D problem) to account for transport effects.
Initiation of chromosome replication in Escherichia coli: II. Analysis of the control mechanism

Abstract Various models for the control of the timing of initiation of chromosome replication in Escherichia coli B r have been analyzed. Control mechanisms which require protein synthesis, rifampicin-sensitive RNA synthesis or a fixed cell size at the moment of initiation are judged to be unlikely. Furthermore, evidence for an involvement of two distinct classes of proteins in the preparation for initiation, distinguishable by the sensitivity of their synthesis to chloramphenicol, was not detected. The timing of initiation seems to be controlled by envelope synthesis, apparently by elongation of the cell envelope between the origins of envelope- bound sister chromosomes. Studies on the effects of chloramphenicol and penicillin on initiation suggest that this elongation process may encompass, but does not require, septum-crosswall formation. As a possible mechanism for the control process, it is proposed that the bacterial chromosome contains a segment involved in initiation of chromosome replication. One end of this segment is attached to the cell envelope and the other end is the locus at which replication is initiated (the chromosomal origin). An envelope-bound replication apparatus is driven along the segment by means of envelope growth between it and the attachment site. When the replication apparatus reaches the origin, chromosome replication initiates. The membrane distance now existing between the attachment site and the replication apparatus could define a membrane region for DNA replication in the cell, approximately equal in length to an Okazaki fragment. After replication begins, the new envelope attachment site and replication apparatus are formed, perhaps through transcription of genes in the initiation segment, and envelope growth begins again between them in preparation for the next initiation. By this means, the timing of initiation is determined by the rate of envelope growth.
Cholesterol modulates membrane traffic along the endocytic pathway in sphingolipid-storage diseases.

Cholesterol modulates membrane traffic along the endocytic pathway in sphingolipid-storage diseases
From "Somatic Scandals" to "A Constant Potential for Violence"? The Culture of Dissection, Brain-Based Learning, and the Rewriting/Rewiring of "The Child".

Within educational research across Europe and the US, one of the most rapidly traveling discourses and highly funded pursuits of the moment is brain-based learning (BBL). BBL is an approach to curriculum and pedagogical decision-making that is located within the new field of educational neuroscience. In some strands of BBL research the structure and function of the brain is located causally, as providing the sole and/or most important basis for making decisions about what and how to teach children. This article analyzes the “messy and numberless beginnings” of the hope placed upon neurological foundationalism to provide a solution to the “problem” of differences between students and to the achievement of educational goals. Rather than arguing for or against educational neuroscience, the article moves through five levels to examine the conditions of possibility for subscribing to the brain as a causal organological locus of learning. It maps pertinent historical conditions, including the relationship betwe...
Ultraweak simultaneous signal detection with theoretical phase calculation approaches

This paper presents applications of a generalized theoretical analysis of Tsui's phase measurement approach to detection of N - 1 ultraweak signals. A closed-form analytical expression is obtained for one application. A detection approach is presented for real-time estimation of the slope and curvature of sampled data of the instantaneous frequency. This approach provides the capability for early simultaneous signal detection and extraction of signal parameters. The capability for N = 4 simultaneous signals is desired for electronic warfare (EW) receivers.
THE APPLICATION OF A PERSONNEL MONITORING SYSTEM TO POPULATION DOSIMETRY OF BACKGROUND RADIATION

Abstract A field study was undertaken to evaluate the use of pocket ion chamber dosimeters for measuring population dose to background radiation. The chambers were charged to a low voltage to minimize leakage and read after exposure with a pulse-reading method. The method had a sensitivity reported to be 1 mr ± 0.2 mr. Special tests were devised for selection of stable and reproducible ion chambers. The dosimeters were worn by individuals for a week at a time over a five-week period and calibrated and standardized after each week of use. Results of an analysis of variance on the standardization data obtained with 41 dosimeters over the period of use are presented. The tests showed that after field use, the system, including reader plus dosimeters, showed increased variability over the variability at the beginning of the tests. The leakage of the dosimeters was also apparently increased in field use over that found in laboratory experiments. The study showed the need of frequent testing in the field of any system used for population dosimetry at the low levels characteristic of background radiation. The design of a study of population exposure to background radiation with personnel monitoring devices is discussed. Formulas are presented for determining the total number of dosimeters to use and the number of dosimeters to assign per individual, based on initial pilot studies. The test data obtained in this survey should be useful for comparison with test data on other dosimeter systems, such as the thermoluminescent type in evaluating the performance of detection systems for the measurement of low-level population exposure.
RG decimation-based approach to confinement and computation on coarser lattices

A systematic procedure is presented for connecting short to long scales in LGT. Approximate decimations are used which can provide both upper and lower bounds on the partition function. Its exact value is then obtained by interpolation between the bounds. By iterating the procedure representations of the partition function as well as other physical quantities can be obtained on progressively coarser lattices. For SU(2) IR flow into the confining strong coupling regime results for any initial β .
Ultrastructural Changes During the Yeastlike to Mycelial-Phase Conversion of Blastomyces dermatitidis and Histoplasma capsulatum

Fine details of the sequential anatomical events occurring during yeast to mold morphogenesis of the dimorphic fungal pathogens Blastomyces dermatitidis and Histoplasma capsulatum as seen in ultrathin sections are described and illustrated by electron micrographs. Discrete intracytoplasmic membrane systems intimately associated with the plasma membrane were observed to be formed within 6 to 8 hr after induction of the conversion process. Within 12 to 18 hr, an intermediate or transitional cell with Woronin bodies at the septum was formed from the converting yeastlike cell. Both cells were noted to contain increased numbers of mitochondria. At approximately 48 hr from the initial induction of the conversion stimuli, the newly forming hyphal cells were observed to produce postconversional intracytoplasmic membrane systems seen normally in the ultrastructural organization of the fully established mycelial-phase cell. These membrane systems appear to be associated with normal septal formation. Although minor variations of time were observed in the occurrence of the sequential events, it is suggested that yeastlike to mycelial-phase conversion of these two fungal pathogens proceeds via a similar mechanism of ultrastructural reorganization.
Methods and circuits for focal-plane computation of features in CMOS visual sensors

Feature detection, and tracking is a fundamental problem in computer vision research. By detecting and tracking features in an image sequence it is possible to recover information about both the motion of the viewer and the structure of the environment. The selection of features is a computationally intensive task. We derive two low-complexity algorithms that are suitable for integration in a CMOS sensor with focal-plane processing. We review the two algorithms and the circuits that implement them. We presents results from accurate simulations and experimental results from fabricated CMOS sensors.
Neural Circuitry: Seeing the Parts That Make the Picture

What are the neural correlates of vision? A recent study on Drosophila has described the incredible neuronal diversity in the fly visual system, and traced the circuits that underlie color vision.
Local Excision of Rectal Cancer

The prospect of treating a rectal cancer often leads to significant fear among patients because of the possibility of a permanent colostomy. Although radical resection, in particular abdominoperineal resection, has been used effectively for rectal cancer treatment, other techniques such as local excision with or without adjuvant therapy have been used with significantly less morbidity than that of the abdominoperineal resection, with excellent cure rates. There are essentially three local excision techniques that can be used to remove a small rectal cancer completely. Selection criteria are critical for choosing the appropriate patient for these techniques. Tumors must be less than 4 cm in diameter and take up less than 40% of the rectal wall circumference. They also need to be relatively close to the dentate line and have no evidence of any invasion into the mesorectum or perirectal nodes. Preoperative staging with endorectal ultrasonography, computed tomography, and digital examination helps select appropriate patients. Retrospective series have shown significant success using local excision techniques, with local recurrence rates ranging from 0% to 11% for early-stage lesions. Prospective series have shown similar recurrence rates. Postoperative function with or without adjuvant therapy has not been adequately documented along with quality of life and must be part of any future reports on local excision techniques as well as all rectal cancer treatment studies. Local excision does, however, seem to provide adequate treatment in well selected patients and provides a less morbid alternative to the treatment of rectal cancer than radical resection, particularly abdominoperineal resection, which obligates the patient to a permanent colostomy.
Effects of delayed visual feedback on handwriting in Parkinson's disease

Parkinson's disease (PD) affects fine motor control, and handwriting may be particularly affected. Several researchers have postulated that PD patients become overly dependent on visual feedback, although prior results have been inconsistent. Discrepancies may be due to the presence or absence of a spatial target, and to medication effects. In the present study, we compared five nondemented PD subjects with five age-matched controls on a handwriting task performed with and without guidelines. Visual feedback was either normal or delayed, to assess dependency on visual information. Effects of medication were assessed by testing PD subjects in undermedicated and well-medicated states. Of the five PD subjects, two wrote in a manner similar to controls across all conditions, two consistently used a non-ballistic mode of writing, and one was micrographic. All PD subjects except the micrographic subject modified their handwriting in response to delayed feedback in a manner similar to controls. Medication affected PD subjects differently, producing an increase in size for the micrographic subject, and an increase in acceleration in the two PD subjects with normal writing. Comparisons of group effects with individual profiles illustrate the importance of recognizing individual differences within PD samples.
Mixed-mode, high-cycle fatigue-crack growth thresholds in Ti–6Al–4V: II. Quantification of crack-tip shielding

Abstract The role of crack-tip shielding in influencing mixed-mode (mode I+II) fatigue-crack growth thresholds for large, through-thickness cracks in a Ti–6Al–4V turbine blade alloy is examined under high-cycle fatigue loading conditions, i.e., at a loading frequency of 1000 Hz in ambient temperature air for load ratios ( K min / K max ) of R =0.1–0.8. Techniques are developed to quantify crack-tip shielding with respect to both the mode I and mode II applied loading, enabling an estimation of the shielding-corrected, crack-driving forces actually experienced at the crack tip ( ΔK I,TH,eff and ΔK II,TH,eff or ΔG TH,eff ). In Part I, it was shown that when the crack-driving force is characterized in terms of the range in strain-energy release rate, ΔG , which incorporates contributions from both the applied tensile and shear loading, the mixed-mode (I+II) fatigue-crack growth resistance increases monotonically with the ratio ΔK II / ΔK I . When the fatigue-crack growth thresholds are expressed in terms of the near-tip (shielding-corrected) crack-driving force, this increase in crack-growth resistance with increasing mode mixity is markedly reduced. Moreover, for all mode mixities investigated, the near-tip mixed-mode fatigue threshold is lower than the applied (global) value, with the effect being particularly pronounced under shear-dominant loading conditions. These observations illustrate the prominent role of crack-tip shielding for the mixed-mode loading of fatigue cracks with crack-wake dimensions large compared with microstructural size scales; specifically, they indicate that the elevation of the ΔG TH fatigue-crack growth threshold with increasing applied mode mixity is largely due to a shear-induced enhancement of crack-tip shielding.
Differential distribution of NMDA receptor subunit mRNA in the rat cochlear nucleus

The distribution and expression of mRNAs for different subunits of the N-methyl-D-aspartate receptor (NMDAR) were examined in the cochlear nucleus (CN) of the rat using radioactive in situ hybridization methods. Heavy labeling for NMDAR1 subunit mRNA was observed in all major CN neuronal types with lower labeling for NMDAR2A, 2B, 2C, and 2D mRNA. Silver grain counting was used to compare expression of different NMDAR2 subunits between six of the major CN cell types. Small cells of the small cell cap/shell area had the highest expression of NMDAR2A-C subunit mRNAs of the cell types assessed. These small cells as well as fusiform and corn cells of the dorsal cochlear nucleus had higher NMDAR2C than other NMDAR2 subunits, providing these neuron types with a distinct expression pattern or profile. The other three cell types assessed, spherical bushy cells, granule cells, and octopus cells had relatively equivalent levels of NMDAR2A-C subunit expressions, providing a second distinct profile. NMDAR2D mRNA had low expression in all six cell types assessed.
The suppressant effect of ethanol, delivered via intrahippocampal microdialysis, on the firing of local pyramidal cells in freely behaving rats

Abstract Intrahippocampal microdialysis was performed on 14 freely behaving rats, and the firing of pyramidal cells within the dialysis area was recorded. In one group of rats, the microdialysis was conducted only with artificial cerebrospinal fluid (ACSF) for 2–4 h. In this control group, the recorded neurons displayed normal firing patterns. In another group, ACSF was replaced for 30–60 min with various concentrations of ethanol to deliver this drug via the microdialysis probe into the cell recording area. Ethanol at the concentration of 5% (w/v) significantly and reversibly suppressed the firing of the recorded neurons. The marked firing rate alterations were not accompanied with apparent changes in the hippocampal EEG activity or the behavior of the rats, indicating localized drug actions. These data demonstrate for the first time that in the physiologically functioning brain, ethanol exerts principally a suppressant effect on the electrical activity of hippocampal pyramidal cells.
Brownian Particle Distribution in Tube Flows

A rigid spherical particle translating at small tube Reynolds number in a shearing flow experiences lateral migration due to small inertia and wall effect. In a suspension flow of sufficiently small particles, Brownian motion is another factor. In this work, we investigate this migration phenomenon of Brownian particles in a pressure-driven flow for a range of particle volume fractions (φ) much less than 0.01. The flow velocity is varied, which results in bulk Peclet number (Pe) ranging over four orders of magnitude. Both the velocity and the particle distributions were measured. It has been found that when Pe is smaller than 1000, particles migrate away from the channel wall, and that the particle concentration in regions remote from the wall (more than 10 particle diameters) is nearly uniform; When Pe increases beyond 1000, particles move toward a preferred position with the migration effect becoming progressively stronger as Pe increases.Copyright © 2004 by ASME
Effects of mutations in SGS1 and in genes functionally related to SGS1 on inverted repeat-stimulated spontaneous unequal sister-chromatid exchange in yeast

The presence of inverted repeats (IRs) in DNA poses an obstacle to the normal progression of the DNA replication machinery, because these sequences can form secondary structures ahead of the replication fork. A failure to process and to restart the stalled replication machinery can lead to the loss of genome integrity. Consistently, IRs have been found to be associated with a high level of genome rearrangements, including deletions, translocations, inversions, and a high rate of sister-chromatid exchange (SCE). The RecQ helicase Sgs1, in Saccharomyces cerevisiae, is believed to act on stalled replication forks. To determine the role of Sgs1 when the replication machinery stalls at the secondary structure, we measured the rates of IR-associated and non-IR-associated spontaneous unequal SCE events in the sgs1 mutant, and in strains bearing mutations in genes that are functionally related to SGS1. The rate of SCE in sgs1 cells for both IR and non-IR-containing substrates was higher than the rate in the wild-type background. The srs2 and mus81 mutations had modest effects, compared to sgs1. The exo1 mutation increased SCE rates for both substrates. The sgs1 exo1 double mutant exhibited synergistic effects on spontaneous SCE. The IR-associated SCE events in sgs1 cells were partially MSH2-dependent. These results suggest that Sgs1 suppresses spontaneous unequal SCE, and SGS1 and EXO1 regulate spontaneous SCE by independent mechanisms. The mismatch repair proteins, in contradistinction to their roles in mutation avoidance, promote secondary structure-associated genetic instability.
Simpson's rule of discretized Feynman path integration

We suggest a Simpson's rule for discretized Feynman path integral approximation of density matrix element. For a class of bounded below potential functions, we rigorously establish the error boundO(1/N2) for itsN-step discretized representation. As a model, we use harmonic oscillator to compare the Simpson's rule with the conventional trapezoidal rule.
Regulation of ion channel expression by cytoplasmic subunits

Abstract Neuronal and cardiac voltage-gated ion channels contain auxilliary subunits that can profoundly affect the gating of the pore-forming and volgate-sensing α subunits. Recent studies on the structurally similar cytoplasmic β subunits of Ca 2+ and K + channels reveal that these subunits can also exert profound effects on the expression of the integral membrane protein channel components. The mechanisms by which these effects occur are now being elucidated through a combined approach that employs biophysical, pharmacological, cell biological and biochemical techniques.
Refractive index: A probe for monitoring volume relaxation during physical aging of glassy polymers

A positive correlation between refractive index and density has been experimentally illustrated in the literature for numerous materials, including polymers. This relationship was exploited in an attempt to follow the densification of a glassy polymer during the physical aging process. Atactic polystyrene films were aged at 74°C and the refractive index ( n ) was evaluated as a function of aging time ( t a ) using an Abbe refractometer. The refractive index increased linearly with respect to log ( t a ), and this dependence was used in conjunction with experimentally determined values of the thermal expansion coefficient in the glassy state and (∂n/∂T) Pa for unaged polystyrene to determine the volume relaxation rate at 74°C. This rate was similar to that obtained for the same polystyrene material using a precision dilatometer, indicating the possibility for using refractive index measurements to quantitatively assess volume relaxation during physical aging.
A proposed mechanisms for the transient suppression of bacterial luminescence by hydrogen peroxide

Abstract It has been shown previously that bacterial luminescence is reversibly suppressed in vivo and in vitro by both X-rays and hydrogen peroxide. The data presented here show that the mechanisms for this phenomenon is based on the transient oxidation of reduced flavin mononucleotide.
Physics at γγ and eγ Colliders

New developments in linear collider and laser technology should soon make it possible to construct a Photon Linear Collider, where high energy photon beams, produced by Compton backscattering laser photons off linac electrons, are brought into collision with electron beams or with other photon beams. High luminosities, along with control over both the energy distribution and polarization of the photon beams, will give such a facility the potential for a very interesting physics program. In particular, a Photon Linear Collider offers a unique environment for the study of Higgs bosons and discovery of new particles such as excited electron states, supersymmetric particles, heavy charged particle pairs, or any particles with appreciable two-photon couplings. Precision electroweak tests also benefit from such a machine, allowing a test of the three-gauge-boson WWγ vertex. The Photon Linear Collider would serve as an excellent laboratory for Quantum Chromodynamics studies involving photon structure functions, jet and hadron production, and resonance production.
The Yersinia Virulence Factor YopM Forms a Novel Protein Complex with Two Cellular Kinases

Pathogenic Yersinia contain a virulence plasmid that encodes genes for intracellular effectors, which neutralize the host immune response. One effector, YopM, is necessary for Yersinia virulence, but its function in host cells is unknown. To identify potential cellular pathways affected by YopM, proteins that co-immunoprecipitate with YopM in mammalian cells were isolated and identified by mass spectrometry. Results demonstrate that two kinases, protein kinase C-like 2 (PRK2) and ribosomal S6 protein kinase 1 (RSK1), interact directly with YopM. These two kinases associate only when YopM is present, and expression of YopM in cells stimulates the activity of both kinases. RSK1 is activated directly by interaction with YopM, and RSK1 kinase activity is required for YopM-stimulated PRK2 activity. YopM activation of RSK1 occurs independently of the actions of YopJ on the MAPK pathway. YopM is also required for Yersinia-induced changes in RSK1 mobility in infected macrophage cells. These results identify the first intracellular targets of YopM and suggest YopM acts to stimulate the activity of PRK2 and RSK1.