cssi/SciSciGPT-SciSciNet huggingface dataset:
Histologic scoring of gastritis and gastric cancer in mouse models

Histopathology is a defining endpoint in mouse models of experimental gastritis and gastric adenocarcinoma. Presented here is an overview of the histology of gastritis and gastric cancer in mice experimentally infected with Helicobacter pylori or H. felis. A modular histopathologic scoring scheme is provided that incorporates relevant disease-associated changes. Whereas the guide uses Helicobacter infection as the prototype challenge, features may be applied to chemical and genetically engineered mouse models of stomach cancer as well. Specific criteria included in the combined gastric histologic activity index (HAI) include inflammation, epithelial defects, oxyntic atrophy, hyperplasia, pseudopyloric metaplasia, and dysplasia or neoplasia. Representative photomicrographs accompany descriptions for each lesion grade. Differentiation of genuine tumor invasion from pseudoinvasion is highlighted. A brief comparison of normal rodent versus human stomach anatomy and physiology is accompanied by an introduction to mouse-specific lesions including mucous metaplasia and eosinophilic droplets (hyalinosis). In conjunction with qualified pathology support, this guide is intended to assist research scientists, postdoctoral fellows, graduate students, and medical professionals from affiliated disciplines in the interpretation and histologic grading of chronic gastritis and gastric carcinoma in mouse models.
Action-based autonomous grounding

When a new-born animal (agent) opens its eyes, what it sees is a patchwork of light and dark patterns, the natural scene. What is perceived by the agent at this moment is based on the pattern of neural spikes in its brain. Life-long learning begins with such a flood of spikes in the brain. All knowledge and skills learned by the agent are mediated by such spikes, thus it is critical to understand what information these spikes convey and how they can be used to generate meaningful behavior. Here, we consider how agents can autonomously understand the meaning of these spikes without direct reference to the stimulus.We find that this problem, the problem of grounding, is unsolvable if the agent is passively perceiving, and that it can be solved only through self-initiated action. Furthermore, we show that a simple criterion, combined with standard reinforcement learning, can help solve this problem. We will present simulation results and discuss the implications of these results on life-long learning.
Mechanistic insights into high mobility group box-1 (HMGb1)-induced Toll-like receptor 4 (TLR4) dimer formation

Supplemental data for this article can be accessed here.High mobility group box-1 (HMGb1), an endogenous danger-associated molecular pattern protein (DAMP) whose extracellular release has been associated with sterile injury and various inflammatory diseases and conditions, has been shown to be a valuable clinical drug target. Elucidation of the specific interactions with the HMGb1 receptor, Toll-like receptor 4 (TLR4) and adaptor protein myeloid differentiation factor-2 (MD-2), will lead to more precisely targeted therapeutics. We sought to examine detailed interactions and dynamics of the HMGb1 A-box and B-box fragments, as well as the intact protein using in silico protein-protein docking (ZDOCK, ZRANK) and molecular dynamics (Schrodinger Desmond, New York, NY). Mutagenesis and SPR-binding studies allowed us to draw further conclusions regarding the details of the HMGb1-TLR4-MD2 interaction and shed light on the reasons for the opposing biological activities of HMGb1 A-box and B-box fragments. From our findings, we hypothesize that disulfide A-box fragment binds as an anchor toward the TLR4-MD-2 but does not facilitate the TLR4 dimer formation, thereby competing with the HMGb1-binding site and preventing HMGb1-induced signaling and downstream inflammation, whereas the pro-inflammatory B-box fragment retains the MD-2 active conformation and binds to both TLR4 proteins in the complex to aid TLR4 dimer formation, which activates the intracellular signaling for downstream inflammatory pathways and cytokine release. Communicated by Ramaswamy H. Sarma.
Single-cell and single-molecule epigenomics to uncover genome regulation at unprecedented resolution

Recent advances in single-cell and single-molecule epigenomic technologies now enable the study of genome regulation and dynamics at unprecedented resolution. In this Perspective, we highlight some of these transformative technologies and discuss how they have been used to identify new modes of gene regulation. We also contrast these assays with recent advances in single-cell transcriptomics and argue for the essential role of epigenomic technologies in both understanding cellular diversity and discovering gene regulatory mechanisms. In addition, we provide our view on the next generation of biological tools that we expect will open new avenues for elucidating the fundamental principles of gene regulation. Overall, this Perspective motivates the use of these high-resolution epigenomic technologies for mapping cell states and understanding regulatory diversity at single-molecule resolution within single cells.
E-cigarette use and sleep-related complaints among youth.

Abstract Introduction E-cigarette use is highly prevalent among adolescents. However, little research has examined the relationship between e-cigarette use and sleep-related complaints in this population. The objective of this study was to assess whether exclusive e-cigarette, exclusive combusted cigarette, and dual-product use are associated with sleep-related complaints among adolescents. Methods Participants were 9,588 U.S. adolescents from the Population Assessment of Tobacco and Health Study, a nationally representative cohort, followed from 2013 through 2015. Using logistic regression, we examined the cross-sectional association between past-year e-cigarette, combusted cigarette, or dual-product use and past-year sleep-related complaints (bad dreams, sleeping restlessly, or falling asleep during the day), both measured at Wave 2. We controlled for Wave 1 demographic characteristics, emotional and behavioral health, and prior history of e-cigarette use, combusted cigarette use, and sleep-related complaints. Results In unadjusted analyses, e-cigarette, combusted cigarette, and dual-product use were significantly associated with greater odds of sleep-related complaints, compared to use of neither product (e-cigarettes: OR = 1.61, 95% CI 1.34–1.94; combusted cigarettes: OR = 1.62, 95% CI 1.26–2.09; dual-product use: OR = 2.00, 95% CI 1.63–2.46). Associations between e-cigarette and dual-product use and sleep-related complaints remained significant in fully adjusted analyses (e-cigarettes: aOR = 1.29, 95% CI 1.05–1.59; dual-product use: aOR = 1.57, 95% CI 1.24–1.99), whereas associations with combusted cigarette use were significant in all models except the fully adjusted model (aOR = 1.30, 95% CI 0.98–1.71). Conclusions E-cigarette and dual-product use are significantly associated with greater odds of reporting sleep-related complaints among adolescents. Future research should evaluate whether this association may be causal.
A Physics-based Virtual Reality Environment to Quantify Functional Performance of Upper-limb Prostheses

Usability of upper-limb prostheses remains to be a challenge due to the complexity of hand-object interactions in activities of daily living. Functional evaluation is critical for the optimization of prosthesis performance during device design and parameter tuning phase. Therefore, we implemented a low-cost physics-based virtual reality environment (VRE) capable of simulating wide range of object grasping and manipulation tasks to enable human-in-the-loop optimization. Importantly, our novel VRE can assess user performance quantitatively using movement kinematics and interaction forces. We present a preliminary experiment to validate our VRE. Four able-bodied subjects performed object transfer tasks with a simulated myoelectric one DoF soft-synergy prosthetic hand, while wearing braces to restrain different levels of wrist motion. We found that the task completion time was similar across conditions, however limited wrist pronation led to more shoulder compensatory motion whereas challenging object orientation caused more torso compensatory motion.
Open-Source Remote Gait Analysis: A Post-Surgery Patient Monitoring Application.

Critical to digital medicine is the promise of improved patient monitoring to allow assessment and personalized intervention to occur in real-time. Wearable sensor-enabled observation of physiological data in free-living conditions is integral to this vision. However, few open-source algorithms have been developed for analyzing and interpreting these data which slows development and the realization of digital medicine. There is clear need for open-source tools that analyze free-living wearable sensor data and particularly for gait analysis, which provides important biomarkers in multiple clinical populations. We present an open-source analytical platform for automated free-living gait analysis and use it to investigate a novel, multi-domain (accelerometer and electromyography) asymmetry measure for quantifying rehabilitation progress in patients recovering from surgical reconstruction of the anterior cruciate ligament (ACL). Asymmetry indices extracted from 41,893 strides were more strongly correlated (r = −0.87, p < 0.01) with recovery time than standard step counts (r = 0.25, p = 0.52) and significantly differed between patients 2- and 17-weeks post-op (p < 0.01, effect size: 2.20–2.96), and controls (p < 0.01, effect size: 1.74–4.20). Results point toward future use of this open-source platform for capturing rehabilitation progress and, more broadly, for free-living gait analysis.
EP properties of (b, c)-invertible matrices

For any semigroup S and any a,b,c,y∈S, the author in 2012 defined a as having (b,c)-inverse y if y∈bSy∩ySc, yab = b and cay = c (any such y being unique). This simultaneously generalizes several kn...
Complications Following Operative Treatment of Supination-Adduction Type II (AO/OTA 44A2.3) Ankle Fractures

Abstract Introduction There are few published studies that investigate the surgical treatment of supination-adduction (SAD, AO/OTA 44A2.3) ankle fractures. The purpose of this study was to describe the complications and outcomes following operative fixation of SAD type 2 ankle fractures. Materials and methods We identified all SAD-2 ankle fractures that presented at our institution's two hospitals from 2006–2018. Demographics, operative data, and complications (deep infection, superficial infection, delayed union, failure of fixation, and unplanned reoperation) were recorded for all patients. Lastly, all included patients were contacted by telephone for the administration of an 8-question Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference questionnaire (PI). Univariate and multivariate analysis was performed to identify risk factors for complication or poor functional outcome score. Results 65 patients met inclusion criteria. The average time to surgery was 14 days and average follow-up was 20.5 (range: 0.4–60.9) weeks. There were 9 (13.8%) complications (4 deep infections, 3 superficial infections, 1 delayed union, 1 failure of fixation) and 6 unplanned reoperations. Univariate and multivariate analysis failed to identify any statistically significant risk factors for complication or reoperation. Eleven patients participated in the administration of PROMIS score questionnaires at a mean of 3.4 years postoperatively. The average PROMIS Physical Function T-score was 42.3 ± 11.3 and the average PROMIS Pain Interference T-score was 55.8 ± 7.8. Younger age was associated with a higher physical function score. The use of a direct medial approach to the medial malleolus was associated with a lower pain interference score. Conclusion The overall complication rate for SAD (OTA/AO 44A2.3) type 2 ankle fractures is similar to that of the general ankle fracture population. We were unable to identify risk factors for complication or reoperation. Mean patient reported outcomes are within one standard deviation of the general population. Level of evidence III, retrospective cohort study.
Unpaid Work? Emotional Labor Assessments and Episodic Recall Bias in Public Engagement

We test individual-level job-related assessments as a function of a public employee’s induced recall of discrete citizen engagement and one’s intrinsic prosocial motivation. We are interested in wh...
High-Performance Colorimetric Humidity Sensors Based on Konjac Glucomannan.

High-humidity conditions (85–100% relative humidity (RH)) have very diverse effects on many aspects of people’s daily lives. Despite remarkable progress in the development of structural coloration-...
Following Germany's Lead: Using International Monetary Linkages to Estimate the Effect of Monetary Policy on the Economy

Abstract Forward-looking behavior on the part of the monetary authority makes it difficult to estimate the effect of monetary policy interventions on output. We present instrumental variables estimates of the impact of interest rates on quarterly real output for several European countries, using German interest rates as the instrument. These estimates confirm a strong forward-looking bias in least squares estimates that persists even conditional on standard controls for the history of the system. Due to the potential for correlation of output shocks across countries, we interpret our estimates as lower bounds for the effect of monetary policy on real output.
Syntheses and Crystal Structures of a Series of Dysprosium–Manganese–Sodium 12-Metallacrown-4 Compounds with Halogenated Benzoate Bridging Anions

A series of heterotrimetallic dysprosium–manganese–sodium 12-metallacrown-4 compounds has been synthesized and characterized by single-crystal X-ray analysis: DyNaX4[12-MCMn(III)N(shi)-4], where X− = 2-fluorobenzoate (1), 3-fluorobenzoate (2), 4-fluorobenzoate (3), 2-chlorobenzoate (4), 4-chlorobenzoate (5), 3-bromobenzoate (6), and 2-iodobenzoate (7); MC is metallacrown; and shi3− is salicylhydroximate. Each 12-MC-4 framework is comprised of four ring MnIII ions and four shi3− ligands. The oxime oxygen atoms of the shi3− ligands produce a central cavity which then binds one DyIII ion and one Na+ ion on opposite sides. In each molecule four halogenated benzoate anions bridge between the central DyIII ion and the ring MnIII ions via the carboxylate groups. The identity of the halogenated benzoate anion has little effect on the structure of the [12-MCMn(III)N(shi)-4] framework as determined by several metrical parameters: the MC cavity radius, the average cross cavity MnIII–MnIII distance, the average cross cavity oxime oxygen-oxime oxygen distance, and the distance of the DyIII from the oxime oxygen mean plane. For 1–7 these metrical parameters are strikingly similar; thus, providing further reinforcement of one hallmark of metallacrown chemistry—the ability to substitute various components of the molecule without affecting the overall structure which can be used for the fine-tuning of molecular properties. Four 4-fluorobenzoate (4-Fben) anions bridge between the central DyIII ion and the ring MnIII ions in the metallacrown compound DyNa(4-Fben)4[12-MCMn(III)N(shi)-4](H2O)4·4DMF.
Smart Spectrum Switching in Wireless Body Area Networks

Wireless Body Area Network (WBANs) would benefit reasonable after the introduction of mmWaves in the communication. The high frequency spectrum can enhance channel capacity and reduce the package area. It however makes the communication link susceptible to noise interference. As the noise level increases, it restricts the use of mmWave spectrum for high SNR level applications. The paper proposes a method of spectrum switching to tap into advantages of mmWave only when necessary thus minimizing the drawbacks on the overall performance. The hybrid approach of using multiple spectrum exploits the characteristics of high channel capacity and high noise immunity which are found at the extreme ends of the spectrum. This paper compares different threshold parameters to conclude SNR as a more reliable factor. We develop an algorithm based on this threshold and simulate spectrum switching from 5 GHz to 60 GHz where the User Equipment is in constant motion over a range of 100 m. We present the graphical results of variance of SNR, Friis model for path loss and numerically prove a significant increase in the average channel capacity using Shannon's theorem while maintaining SNR above the threshold limit. The paper also presents the challenges reflected by this spectrum switching on the supporting parameters like directivity, energy consumption and beamforming array structures.
Fabrication and performance of diamond field effect transistors, transfer-doped with vanadium pentoxide

Army Research Laboratory (ARL) is developing radio frequency (RF) field-effect-transistors (FETs) on hydrogen-terminated, single-crystal diamond surfaces. By employing advanced fabrication methods, we achieve state-of-the-art device performance with gate lengths below 100 nm. We are exploring methods to improve the stability of fabricated FETs, which is critical for maturation of the technology and its commercial acceptance. DC and RF measurement data will be reviewed and discussed within the framework of improving device yield and reliability.
Assessing predictors of futility in patients receiving massive transfusions.

BACKGROUND Massive transfusions are associated with a high mortality rate, but there is little evidence indicating when such efforts are futile. The purpose of this study was to identify clinical variables that could be used as futility indicators in massively transfused patients. METHODS We retrospectively analyzed 138 adult surgical patients at our institution receiving a massive transfusion (2016-2019). Peak lactate and nadir pH within 24 h of massive transfusion initiation, along with other clinical variables, were assessed as predictors of the primary outcome, in-hospital mortality. RESULTS The overall rate of in-hospital mortality among our patient population was 52.9% (n = 73). Increasing lactate and decreasing pH were associated with greater mortality among massively transfused patients. Mortality rates were ~2-fold higher for patients in the highest lactate category (≥10.0 mmol/L: 25 of 37; 67.6%) compared to the lowest category (0.0-4.9 mmol/L: 17 of 48; 35.4%) (p = .005), and ~2.5-fold higher for patients in the lowest pH category (<7.00: 8 of 9; 88.9%) compared to the highest category (≥7.40: 8 of 23; 34.7%) (p = .016). Increasing age was also associated with higher mortality (≥65 years: 24 of 33; 72.7%) when compared to younger patients (18-64 years: 49 of 105; 46.7%) (p = .010). CONCLUSIONS Peak lactate ≥10.0 mmol/L, nadir pH <7.00, and age ≥65 years were significantly associated with higher rates of in-hospital mortality among massively transfused patients. Incorporating these clinical parameters into a futility index for massive transfusions will be useful in situations where blood products are scarce and/or mortality may be unavoidable.
Evaluation of associations between estimates of particulate matter exposure and new onset type 2 diabetes in the REGARDS cohort.

BACKGROUND Studies of PM2.5 and type 2 diabetes employ differing methods for exposure assignment, which could explain inconsistencies in this growing literature. We hypothesized associations between PM2.5 and new onset type 2 diabetes would differ by PM2.5 exposure data source, duration, and community type. METHODS We identified participants of the US-based REasons for Geographic and Racial Differences in Stroke (REGARDS) cohort who were free of diabetes at baseline (2003-2007); were geocoded at their residence; and had follow-up diabetes information. We assigned PM2.5 exposure estimates to participants for periods of 1 year prior to baseline using three data sources, and 2 years prior to baseline for two of these data sources. We evaluated adjusted odds of new onset diabetes per 5 µg/m3 increases in PM2.5 using generalized estimating equations with a binomial distribution and logit link, stratified by community type. RESULTS Among 11,208 participants, 1,409 (12.6%) had diabetes at follow-up. We observed no associations between PM2.5 and diabetes in higher and lower density urban communities, but within suburban/small town and rural communities, increases of 5 µg/m3 PM2.5 for 2 years (Downscaler model) were associated with diabetes (OR [95% CI] = 1.65 [1.09, 2.51], 1.56 [1.03, 2.36], respectively). Associations were consistent in direction and magnitude for all three PM2.5 sources evaluated. SIGNIFICANCE 1- and 2-year durations of PM2.5 exposure estimates were associated with higher odds of incident diabetes in suburban/small town and rural communities, regardless of exposure data source. Associations within urban communities might be obfuscated by place-based confounding.
Energizing organizational research: Advancing the energy field with group concepts and theories

Abstract While energy research has examined behaviors and decision-making in residential settings, it has largely failed to study these behaviors within the commercial sector. It has also neglected investigating these dimensions from a group level of analysis. Yet groups influence behaviors like energy consumption in addition to individuals, and forms of such influence – like collective outcome efficacy or team cohesion – requires research at the group level. This review offers an overview of the area and tools to start this work, first by examining how three levers of behavior change in energy studies – cognitions, social structures and technologies – have mainly been studied from an individual level of analysis. Second, it reviews energy research in commercial environments and finds that only a small number of studies since 1980 have been undertaken with a group level focus. Given this gap, a typology of key group constructs and levels of analysis was developed and measures were reviewed that fit into this typology. This led to the identification of types of questions that can be asked in each of the technological, structural and cognitive energy areas with a group focus.
An Exploratory Factor Analysis and Reliability Analysis of the Student Online Learning Readiness (SOLR) Instrument

The purpose of this study was to develop an effective instrument to measure student readiness in online learning with reliable predictors of online learning success factors such as learning outcomes and learner satisfaction. The validity and reliability of the Student Online Learning Readiness (SOLR) instrument were tested using exploratory factor analysis (EFA) and reliability analysis. Twenty items from three competencies–social competencies, communication competencies, and technical competencies–were designated for the initial instrument based on the Student Online Learning Readiness (SOLR) Model as a new conceptual model. An exploratory factor analysis (EFA) revealed that four factor-structures of the instrument of student readiness in online learning explained 66.69% of the variance in the pattern of relationships among the items. All four factors had high reliabilities (all at or above Cronbach’s I± > .823). Twenty items remained in the final questionnaire after deleting two items which cross-loaded on multiple factors (social competencies with classmates: five items; social competencies with instructor: five items; communication competencies: four items; and technical competencies: six items). The four-factor structure of the Student Online Learning Readiness (SOLR) instrument has been confirmed through this study. Educators can use the Student Online Learning Readiness (SOLR) instrument in order to gain a better understanding of the level of freshmen college students’ online learning readiness by measuring their social, communication, and technical competencies. In addition, this study examined two factors of social integration in Tinto’s Student Integration Model (SIM) and has introduced the Student Online Learning Readiness (SOLR) conceptual model with the purpose of extending Tinto’s social integration model to online learning environments.
Cyber-physical systems: Dynamic sensor attacks and strong observability

We study cyber-physical systems subject to dynamic sensor attacks, relating them to the system's strong observability. First, we find necessary and sufficient conditions for an attacker to create a dynamically undetectable sensor attack and relate these conditions to properties of the system dynamics eigenvectors. Next, we provide an index that gives the minimum number of sensors that must be attacked in order for an attack to be undetectable. Finally, we illustrate our results with a numerical example on the Quadruple Tank Process.
A Language for Interactive Audio Applications

Interactive systems are difficult to program, but high-level languages can make the task much simpler. Interactive audio and music systems are a particularly interesting case because signal processing seems to favor a functional language approach while the handling of interactive parameter updates, sound events, and other real-time computation favors a more imperative or object-oriented approach. A new language, Serpent, and a new semantics for interactive audio have been implemented and tested. The result is an elegant way to express interactive audio algorithms and an efficient implementation.
Pocket Book of Technical Writing for Engineers & Scientists

The focus of this text is to teach engineering students the skill of technical writing. The book is unique in that it gets to the point, uses practical outlines throughout, and shows students how to produce the most common technical documents step-by-step, in a manner that is fun and interesting to students. Each chapter has an end-of-chapter critique which allows students to implement what they have learned in the chapter. With ABET increasing the emphasis on technical writing, this affordable, straightforward, easy-to-understand text with flexible coverage, would be a perfect fit for your technical writing course. Table of contents 1 Introduction 2 Ethical Considerations 3 Technical Definition 4 Descriptions of a Mechanism 5 Descriptions of a Process 6 Proposals 7 Progress Reports 8 Feasibility and Recommendation Reports 9 Laboratory and Project Reports 10 Instructions and Manuals 11 Research Reports 12 Abstracts and Summaries 13 Grammar, Style, and Punctuation 14 Documentation 15 Visuals 16 Electronic Publishing 17 Presentations and Briefings 18 Business Communications 19 Resumes, Cover Letters, and Interviews 20 Team Writing Index
Development of a multi-use construction engineering and management classroom/laboratory

Engineering education requires a combination of classroom training, hands-on experience, and industry participation. In addition, students must become fairly well versed in the use of the technological tools of the trade. In order to accomplish these goals, engineering programs must develop innovation use of space and provide state-of-the-art technologies that can be used by both the students and the instructional staff. The contents of this paper describe: 1) the overall conceptual plan of the CCL, 2) the proposed use of the CCL (use analysis), 3) the equipment and technologies for the CCL, 4) the phased construction schedule, and 5) a summary of the work completed.
Use of Large-Scale Data Sets to Study Educational Pathways of American Indian and Alaska Native Students

This chapter discusses issues and challenges encountered in using large-scale data sets to study educational experiences and subsequent outcomes for American Indian and Alaska Native (AI/AN) students. In this chapter, we argue that the linguistic and cultural diversity of Native peoples, coupled with the legal and political ways in which education has been used to acculturate and assimilate them, makes it imperative that a full range of social, cultural, and demographic variables be collected and that these data be analyzed, using a theory of change that emphasizes the strengths of AI/AN students and their communities rather than their perceived deficits. We envision this theory of change espousing the use of data to critically unpack and respond to the role of language and culture in shaping pathways to success in education and beyond for AI/AN students. We conclude with recommendations for constructing and analyzing large-scale data sets to better represent the diversity of cultures and experiences among AI/AN students.
Non-Explosive Mass Loss

The various mechanisms whereby stars might lose matter are considered, together with the observational evidence of the mass loss rates associated with these mechanisms. The results are shown in a diagram giving the fractional mass that a star loses by various mechanisms as a function of initial mass.
On moderately exponential time for SAT

Can sat be solved in “moderately exponential” time, i.e., in time p(|F|) 2cn for some polynomial p and some constant c<1, where F is a CNF formula of size |F| over n variables? This challenging question is far from being resolved. In this paper, we relate the question of moderately exponential complexity of sat to the question of moderately exponential complexity of problems defined by existential second-order sentences. Namely, we extend the class SNP (Strict NP) that consists of Boolean queries defined by existential second-order sentences where the first-order part has a universal prefix. The extension is obtained by allowing a ∀...∀∃...∃ prefix in the first-order part. We prove that if sat can be solved in moderately exponential time then all problems in the extended class can also be solved in moderately exponential time.
Quinonoid dihydropterin reductase-I. Purification and characterization of the bovine brain enzyme.

Abstract Quinonoid dihydropterin reductase (DHPR, EC 1.6.99.7) from bovine brain was purified 340-fold over the initial extract to an activity of 76 units/mg of protein with an overall recovery of 10 per cent. Analytical polyacrylamide gel electrophoresis, combined with protein staining, indicated that the single band of purified enzyme could have contained no more than 7% contaminants. Furthermore, using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, only one protein band was observed for the SDS-treated enzyme. Using a sucrose density gradient, the sedimentation coefficient and the molecular weight of the native enzyme were determined to be 3.70 and 47,000± 1,400 respectively. Molecular weight using 10% SDS-gel electrophoresis was found to be 22,400± 230, indicating that the brain reductase is composed of two equivalent subunits. Other characteristics of DHPR which were determined were the isoelectric point (pH 5.7), the K m , for quinonoid 6,7-dimethyl-dihydropterin (18 μM) and the K m for NADH (26 μM). Purified brain DHPR was used as an antigen to produce specific antibodies to the enzyme. The specificity of the antibody was established according to the following criteria: (1) the antibody was found to be a potent inhibitor of partially purified and homogeneous DHPR; (2) a single precipitin arc formed upon running either partially purified or homogeneous DHPR against the antibody on a double immunodiffusion plate, or by immunoelectrophoresis; (3) the antibody inhibited DHPR activity from rat brain, rat kidney and rat liver ; and (4) neither inhibition of activity, nor formation of precipitin arcs was exhibited by the antibody when reacted with other catecholamine-synthesizing enzymes partially purified from different rat tissues.
Colon mucosal cell damage by ammonia in rats.

Colons of male Sprague-Dawley rats were perfused, in situ, with ammonium (NH4+) or sodium (Na+) and acetate (CH3COO-) or chloride (Cl-) to determine the effects of the cations and anions or their interactions on the colon mucosa. Solutions simulating ileal fluid were delivered at 0.4 mL/min at 38 degrees C via cannulae inserted at the cecal-colonic junction. Effluents were collected by cannulae inserted in the anus. In the first experiment, perfusion with the control solution or with the control solution having 35 mmol/L NaCl replaced by equimolar amounts of ammonium acetate, ammonium chloride or sodium acetate showed that only ammonium-containing solutions caused histological damage, loss of mucus, and significant losses of carbohydrate and DNA (P less than 0.05). The losses of carbohydrate and DNA expressed in microgram.cm-1.30 min-1 were as follows: control, 13.4 and 1.0; ammonium acetate, 31.8 and 1.6; sodium acetate, 16.0 and 0.6; ammonium chloride, 24.1 and 1.3, respectively. In the second experiment, perfusion with control fluid containing 35 or 70 mmol/L ammonium acetate at pH 6.8, 7.4 or 8.0 increased carbohydrate and DNA losses into the effluents compared with the pretest period (P less than 0.05), without significant effects related to influent pH. These studies are consistent with the concept that the life span of colon cells is shortened by concentrations of ammonia found in the colon under normal conditions and that ammonia enhances cell proliferation in the colon mucosa.
Ratio images and ultraviolet C excitation in autofluorescence imaging of neoplasms of the human colon

The accepted screening technique for colon cancer is white light endoscopy. While most abnormal growths (lesions) are detected by this method, a significant number are missed during colonoscopy, potentially resulting in advanced disease. Missed lesions are often flat and inconspicuous in color. A prototype ultraviolet spectral imager measuring autofluorescence (AF) and reflectance has been developed and applied in a study of 21 fresh human colon surgical specimens. Six excitation wavelengths from 280 to 440 nm and formulaic ratio imaging were utilized to increase lesion contrast and cause neoplasms to appear bright compared to normal tissue. It was found that in the subset of lesions which were most difficult to visualize in standard color photographs [low contrast lesions, (LCLs)] a ratio image (F340/F440) of AF images excited at 340 and 440 nm produced extraordinary images and was effective in about 70% of these difficult cases. Contrast may be due to increased levels of reduced nicotinamide adenine dinucleotide, increased hemoglobin absorption, and reduced signal from submucosal collagen. A second successful ratio image (R480/R555) combined two reflectance images to produce exceptional images especially in particular LCLs where F340/F440 was ineffective. The newly discovered ratio images can potentially improve detection rate in screening with a novel AF colonoscope.
Descriptive analysis of cocaine use of methadone patients

The increasing prevalence of cocaine use among opioid-dependent participants in methadone treatment has been documented, but there is little information about the quantity-frequency aspects of use. This study examined the cocaine use of methadone maintenance patients to determine amounts and patterns of use as well as use in combination with other drugs. Forty-five cocaine using methadone maintenance patients (78% used i.v.) reported their drug use for each day over the past 7 days after receiving information about their most recent urinalysis test results. Average reported use was 0.23 g cocaine/day on 3.4 days/week. Heroin and cocaine were typically used simultaneously, while only a subset of patients (47%) who used alcohol drank within close proximity to cocaine. Patients who used cocaine with alcohol and/or heroin on the same day (N = 28) reported more cocaine use (M = 1.0 g/week) than patients who used cocaine alone (N = 17; M = 0.49 g/week). The results suggest that methadone maintenance patients generally engage in relatively low dose cocaine use, especially when compared to non opioid dependent patients applying to cocaine treatment programs. The study further shows that patients had clear preferences for drug use combinations, which suggests that interventions for cocaine use might focus on modifying drugs used in combination with cocaine.
Identification of novel gamete receptors that mediate sperm adhesion to the egg coat.

Abstract Mammalian fertilization is initiated by the species-specific binding of sperm to the zona pellucida, or egg coat. Earlier studies suggested that sperm–egg adhesion in mouse is mediated by the binding of β1,4-galactosyltransferase-I (GalT) on the sperm surface to specific glycoside ligands on the egg coat glycoprotein, ZP3. Binding of multiple ZP3 oligosaccharides induces GalT aggregation, triggering a pertussis toxin-sensitive G-protein cascade leading to induction of the acrosome reaction. Consistent with this, sperm bearing targeted deletions in GalT are unable to bind ZP3 nor undergo ZP3-dependent acrosomal exocytosis; however, GalT-null sperm are still able to bind to the egg coat. This indicates that sperm–egg binding requires at least two independent binding mechanisms: a GalT–ZP3-independent event that mediates initial adhesion, followed by a GalT–ZP3 interaction that facilitates acrosomal exocytosis. During the past few years, novel GalT–ZP3-independent gamete receptors have been identified that appear to participate in initial gamete adhesion. On such receptor is SED1, an EGF repeat and discoidin domain protein that coats sperm as they traverse through the epididymis, and which is required for sperm to bind the egg coat. Similarly, a novel egg coat ligand is present on ovulated oocytes, but not on ovarian eggs, and which also appears to function in initial sperm binding. The identification of novel gamete receptors that are required for sperm–egg binding opens up new avenues for the development of specific contraceptive strategies.
The use of intubation and tracheotomy in the treatment of obstructive laryngitis in children

Summary Sixty-three cases of acute inflammatory obstructive laryngitis requiring mechanical relief are reviewed. From the data thus collected and from a study of reported cases, intubation seems the procedure of choice in the management of the acute stage of both diphtheritic and nondiphtheritic laryngeal obstruction. Tracheotomy performed during the acute inflammatory stage is apt to result fatally, whereas when done on specific indication after the acute stage is passed, it is almost uniformly successful. Intubation tubes have not been found to cause damage to the larynx even when left in place for fourteen days. The prognosis in cases of acute obstructive laryngitis in children is chiefly influenced by the duration of the obstruction rather than the duration of the disease.
A Low Percent Ethanol Method for Immobilizing Planarians

Planarians have recently become a popular model system for the study of adult stem cells, regeneration and polarity. The system is attractive for both undergraduate and graduate research labs, since planarian colonies are low cost and easy to maintain. Also in situ hybridization, immunofluorescence and RNA-interference (RNAi) gene knockdown techniques have been developed for planarian studies. However, imaging of live worms (particularly at high magnifications) is difficult because animals are strongly photophobic; they quickly move away from light sources and out of frame. The current methods available to inhibit movement in planarians include RNAi injection and exposure to cold temperatures. The former is labor and time intensive, while the latter precludes the use of many fluorescent reporter dyes. Here, we report a simple, inexpensive and reversible method to immobilize planarians for live imaging. Our data show that a short 1 hour treatment with 3% ethanol (EtOH) is sufficient to inhibit both the fine and gross movements of Schmidtea mediterranea planarians, of the typical size used (4-6 mm), with full recovery of movement within 3-4 hours. Importantly, EtOH treatment did not interfere with regeneration, even after repeated exposure, nor lyse epithelial cells (as assayed by H&E staining). We demonstrate that a short exposure to a low concentration of EtOH is a quick and effective method of immobilizing planarians, one that is easily adaptable to planarians of all sizes and will increase the accessibility of live imaging assays to planarian researchers.
Antiepileptic Drug Monitoring: A Reappraisal

As clinical experience with the pharmacokinetic properties and optimal dosing of the established antiepileptic drugs (AEDs) has increased, frequent monitoring of AED concentration in the blood may be less necessary than it was 15 to 25 years ago. Monitoring continues to be valuable at initiation of treatment, addition or removal of other interacting drugs, at the time of unexpected seizure breakthrough, or when symptoms suggest AED toxicity. Occasional determination to monitor compliance may also be appropriate. Blood level determinations of certain of the new, less familiar AEDs, including felbamate, lamotrigine, and oxcarbazapine, appear to be useful. However, new approaches are needed to monitor the efficacy and possible toxicity of other new AEDs for which the correlation between blood concentration of AED and clinical outcome is less clear. For administration of these AEDs, including gabapentin, tiagabine, and vigabatrin, other indirect measures, such as determination of γ-aminobutyric acid (GABA) levels in the cerebrospinal fluid or by nuclear magnetic resonance spectroscopy, may prove useful. For monitoring compliance, alternate technologies, such as a medication-dispensing vial with an electronic memory chip, may be of clinical value. In the clinical management of patients with epilepsy, blood level monitoring plays an important role, but methods of using this monitoring have evolved with increased experience and the introduction of AEDs with new mechanisms of action.
An alkali resistant factor with B12 activity for protozoa and man.

Un facteur, resistant a l'alcali et thermostable, peut etre extrait du serum de l'homme, du foie de bœuf et des bacteries thermophiles. Ce facteur ressemble a la vitamine B12 par son activite chez le protozaire et l'homme. Il peut resister 30 min a la temp. de 118–121°C en autoclave, dans un milieu contenant l'alcali, pH 11.5–12. Ce facteur caracteristique est distinct de la vitamine B12, de l'hydroxycobalamine, de la coenzyme B12, de l'acide folique, de l'acide folinique, et de l'erythropoietine.
Movements of juvenile black sea bass Centropristis striata (Linnaeus) in a southern New Jersey estuary

Abstract Tag–recapture experiments of black sea bass Centropristis striata (Linnaeus) were conducted in the Great Bay estuary in southern New Jersey U.S.A. to examine habitat fidelity, movements, and growth for recently settled individuals in the first summer ( n =337, 34–106 mm TL ) and the following spring ( n =367, 43–111 mm TL ) in order to determine the temporal and spatial patterns of habitat use. During the 15-month (March 1992–July 1993) study, there were 225 recaptures of 180 fish up to 121 d after their initial release. Recapture frequency was high (31%) for fish released in spring and summer and recently settled fish (21%) released in summer and indicated a high degree of habitat fidelity for both of those age groups during those seasons. Almost all recaptures (99%) were made within 30 m of the release site, and of the 35 fish that were recaptured at least twice, 46% were recaptured at the original capture site. Growth, based on recaptured fish, was fastest during the summer (0.74 mm d −1 ), but averaged 0.45 mm d −1 from spring through fall. The low rate of recapture, as well as shorter recapture intervals, during the fall are consistent with a movement into the ocean at that time. Estimates of total loss (=mortality+emigration) of young-of-the-year released in summer were higher during the first 18 days (0.187 d −1 ) following their release than during subsequent days (0.013 d −1 up to day 88), and averaged 0.033 d −1 for the summer and early fall. In summary, some proportion of the juvenile black sea bass population is resident in polyhaline, subtidal estuarine habitats in the summer and in the spring when they are growing the fastest. As a result, habitat-specific responses during these periods may have important implications for survival and subsequent recruitment to the adult population for this species.
Breast magnetic resonance imaging

Breast MRI is becoming an important tool for the improved management of breast cancer. The technical attributes of high contrast, high-resolution breast MRI acquisitions are summarized. The fundamentals of image interpretation are outlined, including lesion enhancement, morphological features, and extent categories. The indications for breast MRI include compromised mammography, staging of disease within the breast and adjacent structures, difficult histology, and other special diagnostic situations. Patients with compromised mammography include previous surgery, radiographically dense breasts, and silicone augmentation. The improved determination of disease extent aids in the management of breast conservation treatment. Certain lesions, particularly lobular carcinoma and ductal carcinoma in situ, can be better managed with the information available with breast MRI. Other potential indications are also discussed, including patients presenting with positive axillary nodes and no known primary, women with a high risk of malignancy, and recently postoperative breasts with positive margins. The need for MRI stereotaxis is reviewed, with indications and potential solutions. The potential future roles for MRI-directed interstitial hyperthermia are outlined.
Balanced exponential growth of operator semigroups

Abstract AC0-semigroupS(t),t ≥ 0, on a Banach spaceX(weakly, strongly, uniformly) approachesbalanced (or asynchronous) exponential growthif there exists somes ∈ R such that[formula]exists (in the weak, strong, uniform operator topology) andPis not the 0 operator. In this paper, the strong and uniform approach to balanced exponential growth is characterized and applicable sufficient conditions are derived. The results will be applied to models for age-size-structured population dynamics in a forthcoming publication.
Aerobic metabolism is maintained in animal tissue during rapid sulfide oxidation in the symbiont‐containing clam Solemya reidi

Solemya reidi is a gutless clam that contains intracellular, symbiotic sulfur-oxidizing chemoautotrophic bacteria in its gills. It lives in burrows in highly reducing muds rich in sulfide, a compound toxic at low levels to aerobic respiration. In these habitats there is wide variation in levels of O2 and sulfide, both of which are metabolic requirements for this symbiosis. In order to assess whether the animal tissues utilize aerobic or anaerobic ATP-generating pathways in the presence of sulfide, and to determine the sulfide concentrations that might induce a shift to anaerobiosis, clams were incubated in varying levels of sulfide and oxygen. Symbiont-free foot tissues from clams incubated in various levels of sulfide (50–500 μM) were analyzed for a common substrate (aspartate) and product (succinate) of invertebrate anaerobic metabolism. The concentrations of these metabolites were compared with those found in tissues of aerobic and anaerobic controls. Aerobic metabolism was maintained in animal tissues in the presence of up to 100 μM sulfide, levels at which maximum autotrophy has been previously reported; however, at higher concentrations, where inhibition of autotrophy has been reported, the onset of anaerobic pathways was evident. This use of anaerobic pathways was not due to the absence of O2, the classical definition of anaerobiosis, but rather to the inhibitory effect of sulfide on aerobic metabolism. The metabolic flexibility of this species in regard to energy metabolism is clearly advantageous living as it does at the interface between a highly oxic environment and an anoxic, highly reducing one.