cssi/SciSciGPT-SciSciNet huggingface dataset:
A slime of the times: Two cases of acute irritant contact dermatitis from homemade slime

We describe two cases of acute-onset erythema, peeling, and pruritus or tenderness isolated to the palmar surface of the hands. A detailed exposure history revealed significant periods of contact with homemade slime; given the clinical findings and timing of exposure, acute contact dermatitis of the hands was suspected. Symptoms and clinical findings resolved after avoidance of the suspected causative contactants. There are few if any reported cases of contact dermatitis to homemade slime in the literature; this serves to highlight the importance of a thorough exposure history in the evaluation of hand dermatitis.
Introduction: Studying Birds in Time and Space

Birds are of high public interest and of great value as indicators of the state of the environment. Some 11,000 species are a number relatively well to handle. From a scientific point of view, it is not easily answerable what a species is, since speciation and extinction are ongoing evolutionary processes and differentiation among species works on various traits. Contemporary systematics attempts to take into account as many criteria as possible to delimit species. The currently most influential approach is the use of genomic sequences, be it as a neutral marker or to discover the underpinnings of functional traits. The study of the outer appearance of birds nevertheless remains fundamental, since that is the interface between a bird and its biotic and abiotic environment. For the majority of bird species, acquired traits of vocal communication add to this complex. Birds can also vary the timing of important behavior such as breeding or molting. Most fascinating among circannual behavior are the long-distance movements that can quite fast evolve and have genetic bases. Despite such dispersal ability for many bird species, geographic barriers play a large role for distribution and speciation in birds. Extant, former, and potential future ranges of a species can be modeled based on the abiotic niches individuals of this species have. Within a species’ range, genetic and phenotypic traits vary and promote to process toward species splits. Beside geographic frameworks, ecological circumstances play a major role and contribute to natural selection but also trigger individual responses such as phenotypic plasticity, modification of the environment, and habitat selection. Anthropogenic global impacts such as climate and land-use changes (e.g., urbanization) force extant species to accelerated modifications or population splits or let them vanish forever. Only if humans leave more room and time to birds and other organisms can we expect to maintain such a number of diverse bird species, although they will keep modifying, splitting, and becoming extinct—but for natural reasons.
When morphological ability exceeds syntactic ability: A case study.

This article addresses the question of whether children classified as having a specific language impairment are such due to a particular problem in inflectional morphology. This has been claimed to...
Augmented Reality for Browsing Physical Collections in Academic Libraries

Column description. The Future Voices in Public Services column is a forum for graduate students in library and information science programs to discuss key issues in academic library public service...
Cowper's syringocele in the pediatric population: a retrospective study of 122 patients.

Summary Introduction and objective Syringocele is a rare cystic dilatation of the duct of Cowper's gland, afflicting mostly the pediatric population. Syringoceles have a wide range of symptoms and may cause urethral obstruction. The authors analyzed to clarify the clinical manifestation, diagnostic approach, management, and incidence in the pediatric population. Materials and methods All patients (122 cases) diagnosed with a syringocele at the department of Pediatric Urology in a tertiary referral university children's hospital between August 1991 and October 2016 were analyzed retrospectively by assessing medical charts. Results The clinical manifestation, diagnostic findings, and follow-up are summarized in the table. Half of the patients (50.0%) also had typical posterior urethral valves (PUVs) and/or a single valve in the 12 o'clock position (flap-valve). The symptoms of open and closed syringoceles showed no significant difference. Treatment consisted of incision of the syringocele with a diathermia hook. The incidence of urinary tract infection (UTI) before and after surgery in the group that had a syringocele only was significant different. The overall incidence of syringoceles seen at urethrocystoscopy in this series was 3.0%. Discussion This series suggests that the presenting age is strongly related to the consequences of syringoceles, as the youngest half of the patients had significantly more UTIs at presentation than older patients, who presented with significantly more obstructive voiding symptoms, postvoiding residuals, and incontinence. In addition, the younger group had a significantly higher incidence of vesicoureteral reflux and dilatation of the upper urinary tract. The found association between syringoceles and PUV may be due to overgrowth of epithelium, as possible origin in both anomalies. Conclusion With an incidence of 3.0%, syringoceles, in this tertiary referral series, should be considered in the differential diagnosis of obstructive urethral lesions. The presentation ranges between signs of severe obstructions in the prenatal and postnatal period to mild urinary incontinence problems at later age. Urethrocystoscopy proved to be useful in confirming the diagnosis and allows for immediate transurethral incision. Summary Table . Clinical manifestation Most frequent presenting symptoms Urinary tract infection (UTI) (50.0%), Obstructive voiding symptoms (45.9%) Postvoiding residual urine (13.9%) Median age at diagnosis 3.0 (IQR: 0.0–9.0) years Diagnostics (UCS) − 83 closed syringoceles and 31 open syringoceles. − 8 patients had two coexisting syringoceles. − 22 patients had a syringocele without additional urethral abnormalities. Follow-up Median follow up 24.0 (IQR: 7.00–52.50) months 42 (34.4%) patients were symptom-free directly after surgery. 23 (18.9%) patients needed a second incision of the rim of the opened syringocele.
Correlation between crystalline cellulose structure and cellulose synthase complex shape: a spectroscopic study with unicellular freshwater alga Micrasterias

Cellulose is synthesized into fibrils by enzyme complexes called cellulose synthase complexes (CSCs). We analyzed cellulose fibrils produced in a dividing unicellular freshwater alga Micrasterias with vibrational sum frequency generation (SFG) spectroscopy. It is known that cellulose in the daughter semi-cell of Micrasterias is synthesized by the isolated individual rosette-shape CSC, while cellulose in the mother semi-cell is produced by hexagonal arrays of rosette-shape CSCs. Comparing the SFG spectra of cellulose in these two regions of a single cell of Micrasterias showed intriguing correlations between the polymorphic structure and crystal size of cellulose and the shape and size of the CSCs. This information may provide a foundation needed to understand what determines the cellulose structure and crystallinity in plant cell walls.
Child-Oriented Marketing on Cereal Packaging: Associations With Sugar Content and Manufacturer Pledge

ABSTRACT Objective To assess sugar content and child-oriented promotional features on packaging among cereals manufactured by companies with varying Children's Food and Beverage Advertising Initiative (CFBAI) participation. Design Ready-to-eat dry cereals (n = 159) were purchased from southeastern US grocery stores in September 2018. Content analysis of 159 ready-to-eat dry cereal boxes, coded for sugar content and presence of 8 child-oriented features. Main Outcome Measures Frequencies of each promotional feature and number of features per box, level of participation in CFBAI, and sugar content by serving and ounce. Analysis Chi-square tests of independence analyzed correspondence between measures of sugar content. Extent of features per box based on sugar content and CFBAI participation were assessed with analyses of variance (ANOVAs). Results Most cereals (81%) contained Conclusions and Implications Variable cereal-suggested serving sizes may contribute to consumers’ misunderstanding of sugar content. CFBAI manufacturers continue to market cereals with high sugar to children. Food and beverage regulatory policy could be strengthened if CFBAI companies apply marketing pledges to brand mascots, adopt standardized metrics for sugar content, and limit added sugar content to the recommended
Amino acids in the Tagish meteorite.

In their paper “Evidence for sodium-rich alkaline water in the Tagish Lake parent body and implications for amino acid synthesis and racemization,” White et al. (1) make several inaccurate statements about amino acid racemization and prebiotic synthesis. Amino acid racemization in meteorites has been previously discussed in detail (2). White et al. (1) state that during the aqueous alteration phase in the Tagish Lake parent body “aspartic acid…would racemize within ∼176 d” in warm (80 °C) alkaline (pH 9) conditions. The alkaline pH was deduced from their investigation of the mineralogy of the meteorite. It is not apparent on what basis 80 °C was selected as the aqueous … [↵][1]1Email: jbada{at}ucsd.edu. [1]: #xref-corresp-1-1
Colloidal Quantum Wells for High-Efficiency Lasers

Semiconductor nanoplatelets, or colloidal quantum wells, may enable low-cost, high-efficiency lasers at colors throughout the visible spectrum, with potential applications to solid-state lighting.
A comparison of SARS-CoV-2 wastewater concentration methods for environmental surveillance.

Wastewater1 surveillance of SARS-CoV-2 may be a useful supplement to clinical surveillance as it is shed in feces, there are many asymptomatic cases, and diagnostic testing can have capacity limitations and extended time to results. Although numerous studies have utilized wastewater surveillance for SARS-CoV-2, the methods used were developed and/or standardized for other pathogens. This study evaluates multiple methods for concentration and recovery of SARS-CoV-2 and seeded human coronavirus OC43 from municipal primary wastewater and/or sludge from the Greater Seattle Area (March-July 2020). Methods evaluated include the bag-mediated filtration system (BMFS), with and without Vertrel™ extraction, skimmed milk flocculation, with and without Vertrel™ extraction, polyethylene glycol (PEG) precipitation, ultrafiltration, and sludge extraction. Total RNA was extracted from wastewater concentrates and analyzed for SARS-CoV-2 and OC43 with RT-qPCR. Skimmed milk flocculation without Vertrel™ extraction performed consistently over time and between treatment plants in Seattle-area wastewater with the lowest average OC43 Cq value and smallest variability (24.3; 95% CI: 23.8-24.9), most frequent SARS-CoV-2 detection (48.8% of sampling events), and highest average OC43 percent recovery (9.1%; 95% CI: 6.2-11.9%). Skimmed milk flocculation is also beneficial because it is feasible in low-resource settings. While the BMFS had the highest average volume assayed of 11.9 mL (95% CI: 10.7-13.1 mL), the average OC43 percent recovery was low (0.7%; 95% CI: 0.4-1.0%). Ultrafiltration and PEG precipitation had low average OC43 percent recoveries of 1.0% (95% CI: 0.5-1.6%) and 3.2% (95% CI: 1.3-5.1%), respectively. The slopes and efficiency for the SARS-CoV-2 standard curves were not consistent over time, confirming the need to include a standard curve each run rather than using a single curve for multiple plates. Results suggest that the concentration and detection methods used must be validated for the specific water matrix using a recovery control to assess performance over time.
Hypothalamic-pituitary-adrenal axis, subjective, and thermal stress responses in midlife women with vasomotor symptoms.

Objective Dysregulated responses to experimental stress paradigms may indicate exposure to chronic stress. Vasomotor symptoms (VMS) are linked with diminished quality of life and psychological stress, but induced stress responsivity has received limited investigation. We examined whether women with and without VMS differ in their evoked hypothalamic-pituitary-adrenal axis, subjective, hemodynamic, and thermal stress responses. Methods A total of 37 midlife women (27 VMS+; 10 VMS-) completed 2 experimental stress paradigms: (1) Montreal Imaging Stress Task (MIST; computerized social-evaluative stressor) and (2) Quantitative Sensory Testing (QST; thermal stress task). Responses on a five-domain (range 0-50) Visual Analog Scale, salivary cortisol (hypothalamic-pituitary-adrenal axis), and hemodynamic indices (blood pressure, heart rate) were measured before and after each task to compare within-person change between groups. Thermal sensitivity was assessed on the QST. Results On the MIST, the VMS+ group showed a smaller cortisol release (0.01 vs 0.07 μg/dL; P = 0.046; corresponding to 54% vs 83% increases), and subjective stress response (21.2- vs 31.1-point Visual Analog Scale increase, P = 0.05; corresponding to 2427% vs 2863% increases) but no hemodynamic difference, compared to the VMS- group. The QST did not provoke stress responses via cortisol release or subjective report, but the VMS+ group tended to perceive heat at a higher temperature (38.5°C vs 36.4°C, P = 0.08). Conclusions Women with VMS exhibited both diminished cortisol and subjective stress responses to the MIST, and reduced thermal sensitivity on QST compared to women without VMS. Dysregulated stress responsivity provides preliminary evidence suggesting that VMS may represent a chronic stress condition.
Results of a Randomized Trial Testing the Efficacy of Tele-Savvy, an Online Synchronous/Asynchronous Psychoeducation Program for Family Caregivers of Persons Living with Dementia.

Background and objectives Family caregivers will grow in number as dementia prevalence increases, underscoring the continued importance of equipping these individuals for their new roles and ameliorating the adverse effects of caregiving. Research design and methods A three-armed, waitlist, randomized trial design tested Tele-Savvy, an online adaptation of a successful in-person psychoeducation program, the Savvy Caregiver. Tele-Savvy is delivered over 43 days to groups of 6-8 caregivers in seven weekly synchronous sessions accompanied by 36 brief asynchronous video lessons. We enrolled 23 cohorts of 15 eligible caregivers (N=261), randomized 2:2:1 to active, attention control, and usual care arms. We assessed caregiver psychological well-being and caregiving mastery at baseline and 3, 6, 9, and 12 months. Multilevel linear models assessed outcomes over the three time points examined. The trial was slightly truncated, with DSMB approval, because of the apparent confounding psychological effects of Coronavirus Disease 2019 (COVID-19) restrictions. Results Study findings indicate statistically and clinically significant benefits to Tele-Savvy arm caregivers (with moderate to large effect sizes) in the areas of depression, perceived stress, reaction to care-recipients' behaviors and enhancement of caregiver mastery. Expected benefits for caregiver burden and anxiety were not found. Discussion and implications Findings attest to program efficacy and the viability of employing distance means to improve family caregivers' emotional well-being and sense of mastery in the caregiving role over a 6-month period. Next steps entail finding alternate ways to deliver the program to those with connectivity and/or time constraint problems.
Examining the Effects of Student Participation and Performance on the Quality of Learnersourcing Multiple-Choice Questions

While generating multiple-choice questions has been shown to promote deep learning, students often fail to realize this benefit and do not willingly participate in this activity. Additionally, the quality of the student-generated questions may be influenced by both their level of engagement and familiarity with the learning materials. Towards better understanding how students can generate high quality questions, we designed and deployed a multiple-choice question generation activity in seven college-level online chemistry courses. From these courses, we collected data on student interactions and their contribution to the question-generation task. A total of 201 students enrolled in the courses and 57 of them elected to generate a multiple-choice question. Our results indicated that students were able to contribute quality questions, with 67% of them being evaluated by experts as acceptable for use. We further identified several student behaviors in the online courses that are correlated to their participation in the task and the quality of their contribution. Our findings can help teachers and students better understand the benefits of student-generated questions and effectively implement future learnersourcing activities.
Calculated phonon modes, infrared and Raman spectra in orthorhombic α − MoO3 and monolayer MoO3

Orthorhombic α−MoO3 is a layered oxide with various applications and with excellent potential to be exfoliated as a 2D ultra-thin film or monolayer. In this paper, we present a first-principles computational study of its vibrational properties. Our focus is on the zone center modes, which can be measured by a combination of infrared and Raman spectroscopy. The polarization dependent spectra are simulated. Calculations are also performed for a monolayer form in which “double layers” of Mo2O6, which are weakly van der Waals bonded in the α-structure, are isolated. Shifts in phonon frequencies are analyzed.
New calibrated zonal model (POMA+) for temperature and airflow predictions

Abstract In building engineering and in the area of thermal environment, various modeling methods advanced to predict either the building energy consumption or airflow and temperature distribution within buildings. These methods are based on the different level of simplifications, the conservation equations used, the accuracy and the applications targeted. A new zonal model POMA+ has been developed to predict temperature and airflow distribution within any room of a building. The main objective of this work is to develop an evaluated and robust zonal model that can be used for building design and thermal analysis. This model has been evaluated by comparison to other models: existing zonal models and experimental data obtained from Minibat experimental chamber. The shuffled complex evolution method, as well as experimental results have been used together to calibrate the new zonal model and improve its prediction. The calibrated model shows a better prediction of airflow, temperature and pressure comparatively to the existing models for all case studies. Finally, multiple error measures have been used to evaluate the quality of the new calibrated model.
Single crystal plastic behavior of a single-phase, face-center-cubic-structured, equiatomic FeNiCrCo alloy ☆

Abstract To understand the fundamental deformation mechanisms of compositionally complex alloys, single crystals of a multi-component equiatomic FeNiCoCr alloy with face-center-cubic (FCC) structure were grown for mechanical studies. Similar to typical FCC pure metals, slip trace analyses indicate that dislocation slips take place on (1 1 1) planes along [ 1 1 ¯ 0 ] directions. The critical resolved shear stress (CRSS) obeys the Schmid law at both 77 and 293 K, and tension–compression asymmetry is not observed. Although this material slips in a normal FCC manner both at 293 and 77 K, the strong temperature dependence of the CRSS is abnormal in comparison to the typical FCC metals.
Glucagon and Diabetes Mellitus

Publisher Summary This chapter reviews the role of glucagon in normal and abnormal carbohydrate metabolism. Diabetes mellitus is a bihormonal disease, which involves alpha cells and beta cells, and the plasma glucagon level of patients with genetic diabetes mellitus is increased at all times throughout life relative to the prevailing glucose concentration. However, to comprehend the dysfunction of the alpha cells in diabetes, it is necessary to first consider their normal function. Glucagon and insulin act in diametrically opposite ways on their common target tissues. Glucagon increases the production of glucose by the liver through enhanced glycogenolysis and gluconeogenesis; on the other hand, insulin decreases hepatic glucose production by inhibiting glycogenolysis and gluconeogenesis. In adipose tissues, glucagon increases lipolysis, insulin reduces lipolysis, by reducing the concentration of cyclic AMP, while increasing lipogenesis. Insulin serves as the hormone of exogenous nutrient storage by promoting the entry of ingested nutrients into liver, fat, and muscle cells, while glucagon serves as the hormone of endogenous nutrient production by distributing stored glucose or free fatty acids to needy tissues.
The Automated General Manager: An Unbiased, Backtested Algorithmic System for Drafts, Trades, and Free Agency that Outperforms Human Front Offices

I introduce an automated system and interactive tools for NBA teams to better decide who to draft, who to trade for, and who to sign as free agents. This automated general manager can serve either as an expert-system replacement or a complement to a team's front office, and also as a calibrating benchmark to compare against actual team building performance. Backtested over the past ten years, the automated GM outperforms every single team, and by substantial margins that often represent a major portion of the team's market value. From draft decisions alone, the average team lost about $130,000,000 worth of on-court productivity relative to what they could have had with the automated GM; this shortfall represents about a quarter of the average franchise value. Historically the automated GM's choices would have produced about twice as much as the human choices actually did: approximately one extra win per year per draft pick. The system is calibrated using an innovative extension of traditional machine learning methods, applied to a uniquely broad historical database that incorporates both quantitative and qualitative evaluations, in a way that avoids possible survivorship bias, and for a variety of performance metrics; it is thus robust, comprehensive, realistic, and does not overfit information from the future.
The Word and the Law

I begin with an analysis of Ball, The Word and the Law, which combines, in an extraordinary way, law, theology, and literature. In each case Ball defines the text or discipline as placing a responsibility upon the member of the relevant community -- the reader, the writer -- not simply to replicate what the text seems to require, but to create meanings of his or her own out of the material offered. I show this responsibility might be discharged in each of the three fields through a reading of chapter 6 of the Gospel of John, through consideration of the process of legal interpretation, and through an analysis of a recent play by Francois Ost, Antigone Voilee (which places the problem of Sophocles' Antigone in a new context, that of the dispute in francophone Europe over rules prohibiting schoolgirls from wearing the veil required by their religion).
John Locke and the Ethics of Belief: Rationality in everyday life

“We should not judge of things by men's opinions, but of opinions by things.” ( Conduct of the Understanding, §24; Works 11, 363). “God has made the intellectual world harmonious and beautiful without us; but it will never come into our heads all at once; we must bring it home piece-meal, and there set it up by our own industry, or else we shall have nothing but darkness and a chaos within, whatever order and light there be in things without us.” ( Conduct of the Understanding, §38; Works 11, 385) THE VISION: LET REASON BE YOUR GUIDE IN BELIEVING Introduction Early in 1671, John Locke had a discussion with some five or six friends in his apartment at Exeter House in London on matters of morality and revealed religion. The discussants, says Locke, “found themselves quickly at a stand by the difficulties that arose on every side. After we had awhile puzzled ourselves, without coming any nearer a resolution of those doubts which perplexed us, it came into my thoughts that we took a wrong course, and that before we set ourselves upon enquiries of that nature it was necessary to examine our own abilities, and see what objects our understandings were or were not fitted to deal with” ( Essay , Epistle to the Reader). This thought, says Locke, “was that which gave the first rise to this Essay concerning the Understanding” (1,1,7).
An Investigation of Practices and Tools That Enabled Technology-mediated Caring in an Online High School

The ethic of care has been an important part of the dialogue related to learning in traditional K-12 learning environments particularly because emotional relationships and caring pedagogies have been shown to be particularly important for adolescent learners. However, as online learning has become increasingly popular, there are concerns about the perceived impersonal nature of the online medium, and how this might particularly affect adolescent learners. The purpose of this study was to examine technology choices when experiencing caring interactions in the online schooling context of Mountain Heights Academy (formerly Open High School of Utah). The caring experience of two teacher participants and four of their students was examined through interpretative phenomenological analysis. Results suggest that teacher choices regarding technology use are an integral part of creating caring relationships with students online. The ethics of caring is an essential model in understanding the communication of caring interactions in the online setting.
Neuro-retinal "lentoids" contain no lens antigens. Immunofluorescent criteria.

Summary “Lentoids” differentiating in cultures of dissociated and reaggregated chick 7-day embryo neural retain contain no antigens cross reacting, by immunofluorescent criteria, to total chicken lens antiserum.
A paradigm shift: Technology integration for higher education in the new millennium

National Technology Competencies National technology competency standards for students graduating from secondary schools are seriously being discussed by the U.S. Department of Education (Thomas & Knezek, 1999). Moreover, school districts throughout the country believe technology literacy is a critical factor in equipping students with the skills and knowledge necessary to succeed in the 21 century (Prime, 1998). In fact, many school districts across the country have already placed technology competency requirements upon their teachers and their graduates (Northover, 1999). In conjunction with student requirements, the National Council for Accreditation of Teacher Education (NCATE) is also seriously considering implementing technology competencies for teacher licensure (NCATE, 1999; ISTE, 1999). Groups such as the International Society for Technology in Education (ISTE), a professional education organization, and the CEO Forum, a think tank comprised of twenty business and education leaders based in Washington, D.C., are responsible for recommending guidelines for accreditation to NCATE. The CEO Forum has recommended that teacher training in computer technology become a mandatory component of licensure by 2002 (CEO Forum, 1999; Galagan, 1999). According to the Forum, schoolteachers in the United States are undertrained on using the computer technology available to them. The Forum also estimates that schools spend roughly $88 per student on computer equipment, but only $6 per student on training teachers to use the technology (Galagan). Many teachers are unable to integrate the technology into their lessons because of a lack of training, and only 20% of teachers were comfortable using computer technology in the classroom (Galagan). How does this affect higher education? Faculty members serve as role models for prospective teachers and their use of, and attitudes toward, educational technology can have a significant impact on future teachers’ implementation of A Paradigm Shift: Technology Integration for Higher Education in the New Millennium
A reassessment of resource depletion, market dependency, and culture change on a Shipibo reserve in the Peruvian Amazon

En 1964, le territoire des Indiens Shipibo de l'Amazonie peruvienne fut reduit a une reserve rectangulaire de deux sur sept kilometres pres de la riviere Yarinacocha. Trois etudes menees en 1976, en 1984 puis en 1997 ont montre que cette reduction territoriale eut de graves impacts sur le systeme de subsistance et l'acces aux ressources, notamment aux palmiers sauvages. Les Shipiblo sont devenus dependants de l'economie de marche, celle-ci ayant modifie l'organisation sociale et cree des inegalites dans la distribution des ressources et cause une anxiete face a l'avenir. Le systeme traditionnel de subsistance se fondait sur l'horticulture sur brulis, la peche et la chasse. Cet article propose une synthese des trois etudes menees sur l'economie des Shipibo sur une periode de trente ans.
Volatile constituents of human vaginal secretions.

Abstract Vaginal secretions were serially studied for 44 ovulatory cycles from 12 patients by means of combined gas chromatograph-mass spectrometry to identify small organic volatile compounds. In 10 of these cycles ovulation was documented with plasma radioimmunoassays for progesterone, estrogens, and LH. These secretions contain a complex mixture of acids, alcohols, hydroxyketones, and aromatic compounds. Lactic acid, acetic acid, and urea were found to be present in all patients and underwent sharp cyclical variations in concentration with maxima in all patients occurring at midcycle. Small-chain, volatile C 2 -C 5 aliphatic acids which have been shown to induce mating behavior in male rhesus monkeys were found in only four patients. In these patients the above acids were found predominantly at midcycle and during the luteal phase.
Measuring Share Repurchases

We examine the accuracy of various approximations of firms' repurchases of common stock used in previous studies, and find that decreases in shares outstanding as reported by CRSP and purchases of common stock and preferred stock (adjusted for changes in preferred stock) are good measures of actual repurchases. We also examine how characteristics such as option usage and the announcement of repurchase programs affect the measures. Compustat purchases of common and preferred stock (adjusted for the change in preferred stock) is the most accurate measure of actual repurchases, particularly for firms with high stock options. Further, the choice of proxy can significantly impact research results. Compustat purchases of common stock is the only estimate of actual repurchases that detects the positive relation between repurchases and employee stock options in a multivariate setting.
Organizational Performance Under Critical Situations—Exploring the Role of Computer Modeling in Crisis Case Analyses

Organizations sometimes face critical situations or crises that can induce severe consequences or even disasters if wrong decisions are made. The bulk of crisis management research has relied heavily on case study methods yet often with rhetorical or even inconsistent suggestions. With an exclusive focus on crisis prevention, the issue of how organizations can maintain good performance when faced with critical situations has largely remained unexplored. There is also an apparent lack of consideration regarding how aspects of organizational design and task environment interact and affect organizational performance under critical situations. In this paper, we attempt to address this issue from an open system's perspective and integrate techniques of computational modeling with the analyses of two crisis cases, the Vincennes incident and the Hinsdale incident. The use of a computational model with strong organization theory foundation has provided a systematic mechanism for abstracting empirical information and generating theoretical results, thus complementing conventional case analyses, which thrive on in-depth information but are often limited by the lack of analytical ability to provide theoretical insight that goes beyond empirical descriptions. For the two crisis cases, the study shows, through detailed quantitative illustrations, that the computer model can be very effective in predicting organizational performance and suggesting designs that organizations can employ to mitigate the impact of crises. This study has demonstrated that our approach of computational case analysis can be very successful in providing systematic and explicit guidance for effective crisis mitigation both theoretically and empirically.
Development of a family of unconditionally stable explicit direct integration algorithms with controllable numerical energy dissipation

SUMMARY The implicit dissipative generalized- α method is analyzed using discrete control theory. Based on this analysis, a one-parameter family of explicit direct integration algorithms with controllable numerical energy dissipation, referred to as the explicit KR-α method, is developed for linear and nonlinear structural dynamic numerical analysis applications. Stability, numerical dispersion, and energy dissipation characteristics of the proposed algorithms are studied. It is shown that the algorithms are unconditionally stable for linear elastic and stiffness softening-type nonlinear systems, where the latter indicates a reduction in post yield stiffness in the force–deformation response. The amount of numerical damping is controlled by a single parameter, which provides a measure of the numerical energy dissipation at higher frequencies. Thus, for a specific value of this parameter, the resulting algorithm is shown to produce no numerical energy dissipation. Furthermore, it is shown that the influence of the numerical damping on the lower mode response is negligible. It is further shown that the numerical dispersion and energy dissipation characteristics of the proposed explicit algorithms are the same as that of the implicit generalized- α method. A numerical example is presented to demonstrate the potential of the proposed algorithms in reducing participation of undesired higher modes by using numerical energy dissipation to damp out these modes. Copyright © 2014 John Wiley & Sons, Ltd.
Rindler observers, correlated states, boundary conditions, and the meaning of the thermal spectrum.

Two new results concerning the Minkowski vacuum state as seen by Rindler observers are derived. The first result is that the thermal excitations detected by two causally separated Rindler observers are correlated in both energy and phase. Therefore, the state as seen by these observers is similar to an Einstein-Podolsky-Rosen state. The second result suggests that a Rindler observer detects the same thermal spectrum even if there is a boundary condition beyond his horizon. A discussion of what these effects tell us about the origin of the thermal spectrum follows.
An Evolved Aminoacyl-tRNA Synthetase with Atypical Polysubstrate Specificity,

We have employed a rapid fluorescence-based screen to assess the polyspecificity of several aminoacyl-tRNA synthetases (aaRSs) against an array of unnatural amino acids. We discovered that a p-cyanophenylalanine specific aminoacyl-tRNA synthetase (pCNF-RS) has high substrate permissivity for unnatural amino acids, while maintaining its ability to discriminate against the 20 canonical amino acids. This orthogonal pCNF-RS, together with its cognate amber nonsense suppressor tRNA, is able to selectively incorporate 18 unnatural amino acids into proteins, including trifluoroketone-, alkynyl-, and halogen-substituted amino acids. In an attempt to improve our understanding of this polyspecificity, the X-ray crystal structure of the aaRS-p-cyanophenylalanine complex was determined. A comparison of this structure with those of other mutant aaRSs showed that both binding site size and other more subtle features control substrate polyspecificity.
Experimental study of laminar boundary layer receptivity to a traveling pressure field

Study is made of the production of Tollmien-Schlichting (T-S) waves within a Blasius boundary layer by an externally-imposed, two-dimensional, pressure field of a particular type. The field is that due to flow past a relatively small cylinder aligned parallel to the test plate and normal to the flow. The cylinder was carried on a circular path about an axis located well above the plate and such that the closest approach of the cylinder to the layer was several times the layer thickness or cylinder diameter. The turbulent wake did not, therefore, directly perturb the layer. Through adjustment of the circumferential velocity, the pressure field was swept along a certain region of the plate with controllable speed. Both the pressure field and the layer response are described in detail. It is shown that the production of T-S waves was sharply maximal for the case of circumferential speed near that of freely-propagating T-S waves, and that the coupling efficiency was extremely high for this case of resonance. The relevance of this energy transfer process to T-S wave production by the unsteady pressure fields resulting from wind tunnel wall turbulent boundary layers for both subsonic and supersonic flow is mentioned.
Developmental genetics of Drosophila

Drosophila melanogaster is one of the most valuable organisms in biological research, particularly in the areas of genetics and developmental biology. Drosophila has been used as a model organism in research for almost a century. The organism is easy to breed and has a short life cycle, making it ideal for the study of genetic mutations. The importance to human health and development lies in the homology of Drosophila genes to those in man, e.g., the homeobox gene complex.
Antioxidant and antitranspirant protection of apple foliage against ozone injury

Visible injury to apple foliage from exposure to ozone includes brown stippling on lower leaf surfaces and a light yellow mosaic on upper surfaces. Histologically, chlorophyll is destroyed and palisade and spongy mesophyll cells collapse following disintegration of their protoplasm. Foliar spray applications of the antioxidant, diphenylamine (DPA) or the antitranspirant, Wilt Pruf offer protection against this visible and histological injury. Superior protection results from application of both agents in combination.
Lp boundedness of Marcinkiewicz integral operators

Abstract In this paper we prove the L p boundedness of Marcinkiewicz integral operators associated to compact submanifolds of finite type under the L ( log L ) 1 / 2 condition on the kernel functions. The exponent 1/2 is optimal. We also show that the L p boundedness may fail to hold if the underlying submanifold is not required to be of finite type.
High resolution and image compression using the discrete cosine transform

The information gathering capacity of the visual system can be specified in units of bits/mm2. The fall-off in sensitivity of the human visual system at high spatial frequencies allows a reduction in the bits/mm2 needed to specify an image. A variety of compression schemes attempt to achieve a further reduction in the number of bit/mm2 while maintaining perceptual losslessness. This paper makes the point that whenever one reports the results of an image compression study, numbers should be provided. The first is the number of bits/mm2 that can be achieved using properties of the human visual system, but ignoring the redundancy of the image (entropy coding). The second number is the bits/mm2 including the effects of entropy coding. The first number depends mainly on the properties of the visual system, the second number includes, in addition, the properties of the image. The Discrete Cosine Transform (DCT) compression method is used to determine the first number. It is shown that the DCT requires between 16 and 24 bits/mm2 for perceptually lossless encoding of images, depending on the size of the blocks into which the image is subdivided. In addition, the efficiency of DCT compression is found to be limited by its susceptibility to interference from adjacent maskers. The present analysis suggests that the visual system requires many more bits/mm2 than the results of other researchers who find that .5 bits/mm2 are sufficient to represent an image without perceptible loss.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Characterization of electron microscopes with binary pseudo-random multilayer test samples

We discuss the results of SEM and TEM measurements with the BPRML test samples fabricated from a BPRML (WSi2/Si with fundamental layer thickness of 3 nm) with a Dual Beam FIB (focused ion beam)/SEM technique. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress.
Online packet scheduling with hard deadlines in multihop communication networks

The problem of online job or packet scheduling with hard deadlines has been studied extensively in the single hop setting, whereas it is notoriously difficult in the multihop setting. This difficulty stems from the fact that packet scheduling decisions at each hop influences and are influenced by decisions on other hops and only a few provably efficient online scheduling algorithms exist in the multihop setting. We consider a general multihop network topology in which packets with various deadlines and weights arrive at and are destined to different nodes through given routes. We study the problem of joint admission control and packet scheduling in order to maximize the cumulative weights of the packets that reach their destinations within their deadlines. We first focus on uplink transmissions in the tree topology and show that the well known earliest deadline first algorithm achieves the same performance as the optimal off-line algorithm for any feasible arrival pattern. We then address the general topology with multiple source-destination pairs, develop a simple online algorithm and show that it is O(PM log PM)-competitive where PM is the maximum route length among all packets. Our algorithm only requires information along the route of each packet and our result is valid for general arrival samples. Via numerical results, we show that our algorithm achieves performance that is comparable to the non-causal optimal off-line algorithm. To the best of our knowledge, this is the first algorithm with a provable (based on a sample-path construction) competitive ratio, subject to hard deadline constraints for general network topologies.
Transfusion-associated graft-versus-host disease and blood irradiation.

GRAFI'-VERSUS-host disease (GVHD) , a common sequela of bone marrow transplantation, is also recognized as a rare risk associated with blood transfusion. The disease results from engraftment of immunocompetent donor T lymphocytes into a recipient whose immune system is unable to reject them. The T cells then initiate an immunologic reaction against the recipient's tissues. The donor lymphocytes can be introduced via bone marrow transplantation or transfusion.
Action of the cubitus interruptus-wallace mutant in Drosophila melanogaster: A study of leg morphology on mosaic and haplo-4 flies

The fourth chromosome mutant cubitus interruptus-Wallace(ciW) produces leg, wing, and body bristle aberrations. The effect on the wing is similar to that produced by cubitus interruptus-dominant (ciD) which also has an influence on larval segmentation indicating that it has a regulatory function. Leg morphology of haplo-4, ciW, and mosaic haplo-4:diplo-4, ci/ci+ flies was examined in an attempt to distinguish between a structural and a regulatory function by ciW. Aberrations recovered include failure of segment elongation, intersegmental gaps, duplication of bristles, and segments that are shorter than normal and of greater than normal diameter. Many of these effects are localized, suggesting that ciW may act to maintain cell positional reference. Increased local cell proliferation appears to be one manifestation of loss of the normal function.
A Hybrid Method for Surrogate Model Updating in Engineering Design Optimization

This paper addresses the critical issue of effectiveness, efficiency, and reliability in simulation-based design optimization under surrogate model uncertainty. Specifically, it presents a novel method to build surrogate models iteratively with sufficient fidelity for accurately capturing global optimal design solutions at a minimal cost. The salient feature of the proposed method lies in its unique preference of focusing necessarily high fidelity at potential global optimal regions of surrogate models. The proposed method is the synergic integration of the multiple preference point method, which updates surrogate model at current local optimal points predicted with data-mining techniques in genetic algorithm setup, and the maximum variance point method, which updates surrogate model at the point associated with the maximum prediction variance. Through illustrative comparison studies on thirty different optimization scenarios derived from 15 different test functions, the proposed method demonstrates the tangible reliability advancement. The experimental results indicate that the proposed method can be a reliable updating method in surrogate-model-based design optimization for efficiently locating the global optimal point/points in various kinds of optimization scenarios featured by single/multiple global optimal point/points that may exist at the corners of design space, inside design space, or on the boundaries of design space.Copyright © 2007 by ASME
π 0 Photoproduction from Hydrogen with Linearly Polarized Photons

The asymmetry in the process $\ensuremath{\gamma}+p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}+p$ with polarized photons has been measured at 6 GeV for momentum transfers from $t=\ensuremath{-}0.4 {(\frac{\mathrm{GeV}}{c})}^{2}$ to $t=\ensuremath{-}1.1 {(\frac{\mathrm{GeV}}{c})}^{2}$, using coherent bremsstrahlung from a diamond crystal. A coincidence was made between the recoil proton in a $1.6\ensuremath{-}\frac{\mathrm{GeV}}{c}$ spectrometer and one of the ${\ensuremath{\pi}}^{0}$ decay photons in a Lucite shower counter. The measured asymmetry $\frac{({\ensuremath{\sigma}}_{\ensuremath{\perp}}\ensuremath{-}{\ensuremath{\sigma}}_{\ensuremath{\parallel}})}{({\ensuremath{\sigma}}_{\ensuremath{\perp}}+{\ensuremath{\sigma}}_{\ensuremath{\parallel}})}$ is consistent with strongly dominant natural parity exchange in the $t$ channel.