cssi/SciSciGPT-SciSciNet huggingface dataset:
Degradation of hydrogen peroxide at the ocean's surface: the influence of the microbial community on the realized thermal niche of Prochlorococcus.

Prochlorococcus, the smallest and most abundant phytoplankter in the ocean, is highly sensitive to hydrogen peroxide (HOOH), and co-occurring heterotrophs such as Alteromonas facilitate the growth of Prochlorococcus by scavenging HOOH. Temperature is also a major influence on Prochlorococcus abundance and distribution in the ocean, and studies in other photosynthetic organisms have shown that HOOH and temperature extremes can act together as synergistic stressors. To address potential synergistic effects of temperature and HOOH on Prochlorococcus growth, high- and low-temperature-adapted representative strains were cultured at ecologically relevant concentrations under a range of HOOH concentrations and temperatures. Higher concentrations of HOOH severely diminished the permissive temperature range for growth of both Prochlorococcus strains. At the permissive temperatures, the growth rates of both Prochlorococcus strains decreased as a function of HOOH, and cold temperature increased susceptibility of photosystem II to HOOH-mediated damage. Serving as a proxy for the natural community, co-cultured heterotrophic bacteria increased the Prochlorococcus growth rate under these temperatures, and expanded the permissive range of temperature for growth. These studies indicate that in the ocean, the cross-protective function of the microbial community may confer a fitness increase for Prochlorococcus at its temperature extremes, especially near the ocean surface where oxidative stress is highest. This interaction may play a substantial role in defining the realized thermal niche and habitat range of Prochlorococcus with respect to latitude.
Frequency of Surveillance and Impact of Surveillance Colonoscopies in Patients With Ulcerative Colitis Who Developed Colorectal Cancer.

Abstract Background The risk of developing colorectal cancer (CRC) in patients with chronic ulcerative colitis (UC) is increased. The aim of this study was to evaluate if patients who developed CRC in the setting of UC were undergoing guideline-recommended surveillance colonoscopies and to determine the impact of surveillance on the staging of CRC. Patients and Methods Data was obtained from the Veterans Affairs healthcare system to identify patients with UC and CRC. Stage 0 and I were considered early-stage CRC, whereas stage ≥ II were considered advanced-stage CRC. Patients were considered to have adequate surveillance if they had a colonoscopy within 2 years before developing CRC. We conducted a case-case analysis using multivariable logistic regression to estimate the odds ratio for presenting with advanced-stage CRC associated with lack of adequate surveillance. Results Of the 48 patients, the majority were white (70.8%) and male (100%). Sixty-nine percent of patients had inadequate surveillance. In multivariable analysis, prior adherence to CRC surveillance was associated with a decreased risk of presenting with advanced-stage CRC (vs. early-stage CRC) (adjusted odds ratio, 0.20; 95% confidence interval, 0.05-0.85; P = .029). Conclusion The majority of patients who developed CRC in the setting of UC underwent inadequate surveillance, and they were more likely to present with advanced-stage CRC.
Surface Diffusion — Some General Remarks

The diffusion of adsorbed atoms on surfaces is a subject of considerable intrinsic interest and also important for the understanding of numerous phenomema in chemisorption, catalysis, nucleation, crystal growth, metallurgy, and semiconductor device fabrication. Despite this fact it has not been studied very extensively, in large part because of the experimental difficulties involved. This NATO Advanced Study Institute serves the very useful function of gathering in one place what is currently known about the subject, and also highlights areas in which much more knowledge needs to be accumulated. The purpose of these introductory remarks is not to summarize the contents of this book -- the fruits of rather intensive labor by a number of contributors -- but merely to introduce the subject, to point out very briefly what surface diffusion can tell us, how it may be investigated, and what remains to be done.
The class I-cardiac resynchronization therapy effect?

Objections from die-hard skeptics notwithstanding, cardiac resynchronization therapy (CRT) improves symptoms, ventricular performance, functional capacity, quality of life, and survival in patients with moderate to severe congestive heart failure (CHF). Now, Yannopoulos et al. ([1][1]) propose that
A Two-step Thresholding Algorithm for Image-based Defect Detection in Roll-to-Roll Coating of Cellulose Nanocrystal Films

Roll-to-roll gravure coating is a scalable process to manufacture cellulose nanocrystals (CNC) based films for packaging and printing. In developing effective roll-to-roll (R2R) process control for coating CNC, real-time inline defect detection is needed. In particular, in many image analysis and processing algorithms, automated thresholding is a fundamental step. Otsu's method is one of the most commonly used techniques for automatic thresholding. It is based on a key assumption that the image exhibits a multimodal histogram distribution. CNC coated films have different textures and the associated defects usually occupy a very small portion of the captured image. This results in an image that is difficult for Otsu's method to generate desirable thresholds. In this work, a two-step automatic thresholding algorithm is proposed, where a statistical process control (SPC) based algorithm is employed to determine a preliminary threshold value for removing majority of the background pixels. This will accentuate the pixel-to-pixel variations that will facilitate the use of Otsu's method to determine the final threshold to isolate fine defect regions. Comparative experimental results verified the effectiveness of the proposed method in finding thresholds that segment out defect pixels from different backgrounds and textures associated with roll-to-roll processed CNC films.
Towards an “Anatomically Correct” Model of English Language Literacy

Literacy scholar Alfred Tatum has argued for a model for literacy with African-American male adolescents that includes the particular needs and contexts of this population. He describes this as an ...
Month-Long, In-Home Socially Assistive Robot for Children with Diverse Needs

Socially assistive robotics (SAR) has the potential to close the gap between need and access to individualized, longitudinal support for children with autism spectrum disorders (ASD) that supplements and augments that of therapist, clinicians, and other caregivers. To this end, we developed a fully autonomous SAR system designed for month-long, in-home interventions with children with ASD. In this paper, we investigate a single case study with two siblings; one is typically developing and the other is affected by ASD. To better understand their help-seeking behaviors and engagement patterns, we define and analyze measures of participants’ attentiveness. Our analysis shows that there are strong correlations between attentiveness and challenge level for both participants. We discuss how attentiveness can be used to optimize challenge level, detect help-seeking behaviors, and improve robot feedback for individuals with diverse needs.
A Prion Epigenetic Switch Establishes an Active Chromatin State

Summary Covalent modifications to histones are essential for development, establishing distinct and functional chromatin domains from a common genetic sequence. Whereas repressed chromatin is robustly inherited, no mechanism that facilitates inheritance of an activated domain has been described. Here, we report that the Set3C histone deacetylase scaffold Snt1 can act as a prion that drives the emergence and transgenerational inheritance of an activated chromatin state. This prion, which we term [ESI+] for expressed sub-telomeric information, is triggered by transient Snt1 phosphorylation upon cell cycle arrest. Once engaged, the prion reshapes the activity of Snt1 and the Set3C complex, recruiting RNA pol II and interfering with Rap1 binding to activate genes in otherwise repressed sub-telomeric domains. This transcriptional state confers broad resistance to environmental stress, including antifungal drugs. Altogether, our results establish a robust means by which a prion can facilitate inheritance of an activated chromatin state to provide adaptive benefit.
Learners’ harmonic preferences are modulated by lexical retrieval difficulty

Typological work has established the existence of language universals – features or combinations of features that (co-) occur in unrelated languages more frequently than expected by chance. The origins of language universals are a fundamental question in language sciences as these universals are considered a reflection of cognitive mechanisms underlying human language. In this study, we use a miniature artificial language learning paradigm to explore whether a well-known universal – a preference for harmonic word ordering between adpositional and verb phrases (i.e., placing the head in a consistent position with respect to the complements across the two phrase types) – originates in biases during language learning and whether this preference interacts with memory constraints (operationalized as lexical retrieval difficulty). We first trained participants on miniature languages containing adpositional phrases of a deterministic word order (either prepositional or postpositional inputs) and then briefly exposed them to simple transitive sentences (verb-subject-object and subject-object-verb order, equally frequent in the input). At test, we asked learners to describe simple transitive scenes. We found that in the hard lexical retrieval condition, learners exposed to a postpositional language showed a preference for harmonic ordering but learners of the prepositional language did not, which is only partially consistent to the typological distribution. In the easy lexical retrieval condition, learners of neither the postpositional nor prepositional language showed a preference for harmonic ordering, indicating that this preference is modulated by memory constraints.
Late Life Cognitive Disorders

Just as there are physical changes associated with aging, there are also changes in mental abilities as a function of the normal maturational process. Normal age-related cognitive decline can be difficult to distinguish from the early stages of disease-associated impairment, even for the practiced clinician. Given the presumably long period of time in which neuropathological changes develop, the clinical manifestation of those changes can be subtle and vary considerably between individuals. The presentation of cognitive changes can also be impacted by nonneurologic factors, such as sleep, medications, systemic illness, to name a few. Memory changes are the hallmark of the most common form of dementia, Alzheimer's disease, and memory complaints are common in the aged population. Neuropsychological assessment, formal testing of cognitive abilities, can be useful in discriminating between normal age-related changes and deficits secondary to a disease process. This type of formal assessment takes into account and individual's estimated premorbid abilities to assess whether or not a change has taken place. Performance on cognitive tests is also useful in the differential diagnosis of the various disorders associated with dementia. In this article, risk factors associated with dementia as well as preventative strategies for delaying cognitive disorders of late life are discussed.
Optical second harmonic generation imaging and x-ray diffraction of Cs 1 - x Rb x H 2 PO 4 proton conductor series

The solid acid compound CsH2PO4 (CDP) is a superprotonic conductor for intermediate temperature range fuel cell applications. Doping CDP with rubidium can alter its transition temperature from normal phase to superprotonic phase. Powder samples of Cs1 − xRbxH2PO4 (0 ≤ x ≤ 1) were synthesized with 10 at. % intervals of x and analyzed at room temperature. A powder x-ray diffraction study showed three major structures between the various samples: monoclinic P21/m for x ≤ 0.5 samples, monoclinic P21/c for x = 0.8 samples, tetragonal I-42d for x = 0.9 and 1 samples, and a mixture of these structures in the x = 0.6 and 0.7 samples. Optical second harmonic generation (SHG) microscopy was performed on these samples, and a unique quadrupolar behavior in an SHG polar plot was found and correlated with the monoclinic P21/c structure in the x = 0.8 sample and some part of the x = 0.6 and 0.7 samples. Although in principle this P21/c structure is centrosymmetric with no SHG signal, the loss of local symmetry while maintaining the overall super structure can possibly explain this phenomenon. The tetragonal I-42d structure is noncentrosymmetric and shows dipolar behavior in the SHG polar plot from x = 0.9 and 1 samples and part of the x = 0.6 and 0.7 samples. The monoclinic P21/m structure is centrosymmetric with no SHG signal from the x ≤ 0.5 samples. Our discovery confirms the early finding of phases of Cs1 − xRbxH2PO4 (0 ≤ x ≤ 1) superprotonic conductor series at room temperature and indicates the potential of developing SHG microscopy to study the phases of these compounds at an intermediate working temperature in situ.
The roots of the silver tree: Boyle, alchemy, and teleology

Abstract Though Robert Boyle called final causes one of the most important subjects for a natural philosopher to study, his own treatise on the subject, the Disquisition about Final Causes, has received comparatively little scholarly attention. In this paper, I explicate Boyle's complex argument against the use of teleological explanations for inanimate bodies, such as metals. The central object of this argument is a mysterious allusion to a silver plant. I claim that the silver plant is best understood as a reference to alchemical product: the Arbor Dianae, an offshoot of George Starkey's recipe for the Philosophers' Stone. Then, I show how the context of alchemy not only clarifies Boyle's argument but also places it within a wider dialectic about matter and teleology. I then contrast the parallel arguments of Boyle and John Ray on the question of whether metals have divine purposes and show that the difference is explained by Boyle's belief in the transmutation of metals.
AN ECONOMIC STUDY FOR ESTIMATION WHEAT AND MAIZE PROFITABILITY BY USING SAMPLING TECHNIQUES ACCORDING TO FIELD LOCATION AND WATER IRRIGATION QUALITY IN KAFR EL-SHIKH GOVERNORATE

wheat and corn are very important cereal crops in Egypt on both production and consumption sides. According to their importance, the government of Egypt put a lot of attention to increase their areas, yields, and production .the area of wheat was increased by 3.3 th .feddan yearly the wheat yield by about .007TF, while the production was increased by 23the.Tper year during the period of 1992/2012. The number of factors affecting the crop yield level, irrigation water one of those factors, Measuring the effect of water quality and yield location an irrigation canal represents the research problem. The research was conducted in Kafr Elshikh gov. Data were collected by questionnaire from 36 farms was selected to collect the needed data. Data of costs and returns were collected, The sample was distributed at:1-irrigation water quality (fresh, mixed, and drainage) at equal numbers (12 for each on 3 canals). 2- field location on the canal (front- middle, and the end), 12 fields for each, 4 for each canal. For wheat crop, the results show that a maximum yield was obtimal from fresh water. The average yield was estimated at 16.81 ardabe/ fed. It increased to about 17.56 and /fed in front of the canal fields, 17.72 ardabe/ fed in middle fields, and 15.14 for the ard/fed . The average wheat yield in the mixed water was estimating at 10.2 (6.61 ardabe/ fed, less than fresh water yields, while the drainage water yield was estimated at 17.43 ardabe/ fed(103% from fresh water yield. The differences of yield according to water quality and field location were statistically significant based on ANOVA (analysis of variance). The gross margin indicator was measured to reflect the economic efficiency of using water quality and field location. The results showed that the gross margin of wheat crops in fresh water amounted to LE 6238 per fedden, representing 221% from its value of mixed water (L.E2807)and 123%from its value of drainage water (L.E5070). The differences among those values were statistically significant . For maize crop,the same direction was foundThe average yield for fresh water was estimated at 16.83 ard/F, comparing with 9.54 ard /F for nixed water ,and 15.45 ard /f for drainage water. The differences of yields according to water quality were statistically significant . For field location it was found that the average yield of front canal was 17.09 ard/fed 20ard/F for middle ,and 14 ard /f for end canal fields in fresh water .the differences among yields according to field location were statistically signicanal . The estimates of gross margin indicator showed that ,it was about L.E 3115 in fresh water, L.E28, L. 2677 in mixed water, and L.E1201 in drainage water . The differences of.
DINOSAUR: an integrated cognitive-behavioral treatment for anxiety in young children with ASD.

Background Anxiety disorders are highly prevalent in children and adolescents with autism spectrum disorder and often emerge before the age of 6 years. Yet, only a few studies have examined anxiety treatment for this group. Preliminary evidence from these studies suggests that utilizing cognitive behavioral therapy (CBT) as well as strategies to target intolerance of uncertainty (IU) and parental accommodation, known mechanistic and maintaining factors of anxiety may improve anxiety and optimize outcomes in this age group. Main body To meet this need, we developed an integrated treatment called DINO Strategies for Anxiety and intolerance of Uncertainty Reduction (DINOSAUR), a 12-week group telehealth treatment for 4- to 6-year-old children with ASD. DINOSAUR works with young children and their parents to deliver CBT along with interventions targeting IU and parental accommodation. In this paper, we first discuss the rationale for developing this treatment and then describe a pilot study of its feasibility and preliminary efficacy. Conclusions There is a great need to develop anxiety treatments for young children with ASD. We proposed a novel integrated treatment approach that aims to alter the way young children and parents respond to fear, which could potentially improve short- and long-term mental health outcomes for this age group. Trial registration ClinicalTrials.gov NCT04432077 on June 03, 2020.
Suicidal Ideation Among Transgender and Gender Expansive Youth: Mechanisms of Risk

Purpose: Suicide is a leading public health concern among transgender and gender expansive adolescents, although little research has examined mechanisms through which gender identity is associated ...
TRANSPORT SIMULATION USING THREE DIMENSIONAL ALTERNATING DIRECTION COLLOCATION.

The purpose of this paper is to extend our earlier work on alternating direction collocation methods (ADC) to include three dimensional nonlinear transport simulation. Earlier papers (Celia et al, 1980; Hayes et al, 1981) described the two dimensional linear formulation and the theoretical underpinnings of the methodology. We will not revisit these matters again in this work but rather focus on the generalized, multidimensional non-linear formulation.
Application of liquid chromatography combined with mass spectrometry or tandem mass spectrometry for therapeutic drug monitoring of immunosuppressants

This chapter considers the application of mass spectrometry for the detection and quantification of common immunosuppressants: cyclosporine A, tacrolimus, sirolimus, everolimus, and mycophenolic acid (MPA). The most common application of this approach is performed in whole blood, for all but MPA (serum or plasma), to support routine therapeutic drug monitoring. Topics discussed include preanalytical variables, specimen preparation, reagents for mass spectrometry tests, and the benefits and limitations of mass spectrometry technology.
Project BOOST®: A Comprehensive Program to Improve Discharge Coordination for Geriatric Patients

Hospital discharge is often a stressful and hazardous venture for patients and their caregivers, especially for older adults with complex medical needs. The unfortunately routine discontinuity and fragmentation of care associated with hospitalization generate tangible risks of harm to patients and flummox their caregivers. Project BOOST® (Better Outcomes by Optimizing Safe Transitions) comprehensively aims to enhance transitions of care, improve patient satisfaction, and augment the flow of information between hospitals and primary care and subacute providers. BOOST’s ultimate goal is to coordinate patient-centered care during a hospital discharge transition by ensuring patients and/or caregiver comprehension of instructions, improving hospital to post-acute provider communication, and reducing unnecessary emergency department (ED) visits and rehospitalizations. BOOST® focuses on facilitating interdisciplinary care of patients and utilizes a team approach to assess patients’ risk for rehospitalization linked to planning and executing risk-specific discharge efforts.
The Road from Interdisciplinary Studies to Complexity

The founder of the profession of interdisciplinary studies revisits the intellectual odyssey he undertook in developing a theory of interdisciplinary studies, which eventually led him to complex systems theory. The precise relationship between complex systems and interdisciplinary studies is probed and the implications of that relationship for both theories are critically examined.
Calculating genomic distances in parallel using OpenMP

By finding the corresponding shortest edit distance between two signed gene permutations, we can know the smallest number of insertions, deletions, and inversions required to change on string of genes into another, where insertion, deletion and inversion are the process of genome evolutions. However, it is NP-hard problem to compute the edit distance between two genomes. Marron et al proposed a polynomial-time approximation algorithm to compute (near) minimum edit distances under inversions, deletions, and unrestricted insertions. Our work is based on Marron’s et al algorithm, which carries out lots of comparisons and sorting to calculate the edit distance. These comparisons and sorting are extremely time-consuming, and they result in the decrease of the efficiency. We believe the efficiency of the algorithm can be improved by parallelizing. We parallelize their algorithm via OpenMP on Intel C++ compiler for Linux 7.1, and compare three levels of parallelism: coarse grain, fine grain and combination of both. The experiments are conducted for a varying number of threads and length of the gene sequences. The experimental results have shown that either coarse grain parallelism or fine grain parallelism alone does not improve the performance of the algorithm very much, however, the combination of both fine grain and coarse grain parallelism have improve the performance to a great extent.
Environmental control of ethylene biosynthesis

Ethylene is involved in the regulation of many developmental processes and stress-induced responses of plants. These include fruit ripening, flower fading, promotion of growth in semiaquatic plants and synthesis of defense-related proteins in plants infected by pathogens (Abeles, 1973; Yang and Hoffman, 1984; Ecker and Davis, 1987) Ethylene is synthesized from L-methionine via Sadenosyl-L-methionine and 1-aminocyclopropane- 1 -carboxylic acid (ACC; Yang and Hoffman, 1984). The regulated enzyme of this pathway is, in most known instances, ACC synthase (S-adenosyl-L-methionine methylthioadenosine-lyase, EC 4.4.1.14). A variety of chemical and environmental factors such as physical wounding, chilling, hypoxia, noxious chemicals, and the plant hormone indole-3-acetic acid stimulate ethylene biosynthesis by enhancing the activity of ACC synthase (Yang and Hoffman, 1984). One of the important problems regarding the regulation of ethylene biosynthesis concerned the question whether diverse effectors regulate the expression of one ACC-synthase gene with multiple regulatory elements or whether there are several ACCsynthase genes, each of which is controlled by a specific type of stimulus.
Automated dynamic reconfiguration using AI planning

The goal of this work is to automate the failure recovery in distributed component based systems using a planning based approach in dynamic reconfiguration. Our approach comprises of a three step process i.e. sense-plan-act (SPA). 'Sense' is the process of sensing the state of the system. 'Plan' is the process of finding a target configuration and a subsequent plan that takes the system from the present configuration to a target configuration. 'Act' is the process of executing the plan on the system. This work presents the preliminary ideas and the current status of this work.
Double dissociation of the anterior and posterior dorsomedial caudate-putamen in the acquisition and expression of associative learning with the nicotine stimulus

Tobacco use is the leading cause of preventable deaths worldwide. This habit is not only debilitating to individual users but also to those around them (second-hand smoking). Nicotine is the main addictive component of tobacco products and is a moderate stimulant and a mild reinforcer. Importantly, besides its unconditional effects, nicotine also has conditioned stimulus effects that may contribute to the tenacity of the smoking habit. Because the neurobiological substrates underlying these processes are virtually unexplored, the present study investigated the functional involvement of the dorsomedial caudate putamen (dmCPu) in learning processes with nicotine as an interoceptive stimulus. Rats were trained using the discriminated goal-tracking task where nicotine injections (0.4 mg/kg; SC), on some days, were paired with intermittent (36 per session) sucrose deliveries; sucrose was not available on interspersed saline days. Pre-training excitotoxic or post-training transient lesions of anterior or posterior dmCPu were used to elucidate the role of these areas in acquisition or expression of associative learning with nicotine stimulus. Pre-training lesion of p-dmCPu inhibited acquisition while post-training lesions of p-dmCPu attenuated the expression of associative learning with the nicotine stimulus. On the other hand, post-training lesions of a-dmCPu evoked nicotine-like responding following saline treatment indicating the role of this area in disinhibition of learned motor behaviors. These results, for the first time, show functionally distinct involvement of a- and p-dmCPu in various stages of associative learning using nicotine stimulus and provide an initial account of neural plasticity underlying these learning processes.
EFFECT OF PARTICLE SIZE ON ULTRASONIC DEVULCANIZATION OF TIRE RUBBER IN TWIN-SCREW EXTRUDER

ABSTRACT Ultrasonic devulcanization of tire rubber particles of 10 and 30 meshes by means of a new ultrasonic twin-screw extruder was investigated. The ultrasonic amplitude and devulcanization temperature were varied at a fixed frequency of 40 kHz. The die pressure and ultrasonic power consumption during devulcanization were recorded. The degree of devulcanization was investigated by measuring the cross-link density, gel fraction, and revulcanization behavior. Rubber of 30 mesh exhibited a lower die pressure and higher degree of devulcanization than that of rubber of 10 mesh. Because of the higher level of devulcanization and lower viscosity of devulcanized rubbers at higher amplitudes, the temperature of devulcanized rubbers at the die was reduced with an increase of the ultrasonic amplitude. Generally, the torque at the start of curing and maximum torque on the curing curve measured during revulcanization is higher for rubber of 10 mesh and rubbers devulcanized at a lower temperature. Rheological proper...
Control logic for a 30 cm diameter ion thruster

Tests with a 30 cm thruster having EMT critical components have defined start-up criteria. Of the three phases comprising the start-up mode, the preheat phase is intended to heat critical feed system components to desired temperatures. Of the seven supplies available during the preheat phase, only three were found to be useful for purposes of preheating the thruster. These were the cathode and neutralizer tip heater supplies and the isolator heater supply. If the needed temperatures are attained during preheat, the ignition phase requires only several seconds. The heat phase serves to establish the proper propellant flow rates prior to the transition to the run mode. Using these techniques, a thruster with initial temperatures in the range of -15 to +25 C can be reliably started and provide a 1.0 amp beam within 45 min. High voltage recycle time profiles indicate limitations on several time functions.
Frequency and effect of negative comments (“badmouthing”) on medical students' career choices

BACKGROUND: Some call it “medical bigotry,” and others describe it as the “hidden curriculum,” but, by any name, the superficial and demeaning comments that students hear about particular career choices are thought to play a major role in discouraging the selection of primary care careers. This pape
Lobbying and welfare

Abstract The paper shows that the cost of any distortion, arising without the aid of resource-using lobbying addressed to having the distortion implemented, is not necessarily less than the cost of the same distortion arising with the aid of such lobbying. This refutation of the prevalent assertions to the contrary reflects the second-best nature of the problem at hand.
Online IR system evaluation: online databases versus Web search engines

This study evaluated two different types of online information retrieval (IR) systems: online databases and Web search engines, in terms of user generated criteria. It also compares four types of Web search engines: directories, search engines, meta‐search engines, and specialized search engines. The results show that three elements are essential to users in the evaluation of online IR systems: interface design, system performance and collection coverage. While participants preferred the ease of use and intuitive interfaces of Web search engines, they also liked the credible and useful information offered by online databases. Based on the discussion of advantages and problems of online databases and Web search engines, implications of for the design of IR systems are further suggested.
Low energy ions in the heavy ions in space (HIIS) experiment on LDEF.

We present data from the Lexan top stacks in the Heavy Ions In Space (HIIS) experiment which was flown for six years (April 1984 – Jan 1990) onboard the LDEF spacecraft in 28.5° orbit at about 476 km altitude. HIIS was built of passive (i.e. no timing resolution) plastic track detectors which collected particles continuously over the entire mission. In this paper we present data on low energy heavy ions (10 ≤ Z, 20MeV/nuc < E < 200MeV/nuc). These ions are far below the geomagnetic cutoff for fully ionized ions in the LDEF orbit even after taking into account the severe cutoff suppression caused by occasional large geomagnetic storms during the LDEF mission. Our preliminary results indicate an unusual elemental composition of trapped particles in the inner magnetosphere during the LDEF mission, including both trapped anomalous cosmic ray species (Ne, Ar) and other elements (such as Mg and Fe) which are not found in the anomalous component of cosmic rays. The origin of the non-anomalous species is not understood, but they may be associated with the solar energetic particle events and geomagnetic disturbances of 1989.
Second and third virial coefficients for hydrogen

Second and third virial coefficients for parahydrogen have been derived from closely spaced PVT data from 24 to 100 °K. They are in good agreement at 100 °K with published data for normal hydrogen. Analytical representations of the combined data from about 20 to 423 °K are presented which may be useful in computation of thermodynamic functions of the gas. These formulas are related to those resulting from the use of the Lennard-Jones potential.
THE EFFECTS OF WAVE ESCAPE ON FAST MAGNETOSONIC WAVE TURBULENCE IN SOLAR FLARES

One of the leading models for electron acceleration in solar flares is stochastic acceleration by weakly turbulent fast magnetosonic waves ({sup f}ast waves{sup )}. In this model, large-scale flows triggered by magnetic reconnection excite large-wavelength fast waves, and fast-wave energy then cascades from large wavelengths to small wavelengths. Electron acceleration by large-wavelength fast waves is weak, and so the model relies on the small-wavelength waves produced by the turbulent cascade. In order for the model to work, the energy cascade time for large-wavelength fast waves must be shorter than the time required for the waves to propagate out of the solar-flare acceleration region. To investigate the effects of wave escape, we solve the wave kinetic equation for fast waves in weak turbulence theory, supplemented with a homogeneous wave-loss term. We find that the amplitude of large-wavelength fast waves must exceed a minimum threshold in order for a significant fraction of the wave energy to cascade to small wavelengths before the waves leave the acceleration region. We evaluate this threshold as a function of the dominant wavelength of the fast waves that are initially excited by reconnection outflows.
Virtual Team Trust: Instrument Development and Validation in an IS Educational Environment

Trust is a major factor influencing the cohesiveness among virtual team members. While recent research in the fields of information systems and management has examined this construct, there are no existing instruments that measure all the different bases of trust. Drawing on the literature, three different bases of trust applicable to virtual teams have been identified: personality-based, institutional-based, and cognitive trust, with cognitive trust further subdivided into three dimensions: stereotyping, unit grouping, and reputation categorization. This paper reports on the development of an instrument to capture these three bases of trust. Using exploratory, and thereafter, confirmatory factor analysis, the instrument is validated, and the psychometric properties of the constructs are verified in the context of U.S.-Canadian student virtual teams engaged in systems development projects. In addition to confirming the conceptual bases of trust, the instrument validation process found that stereotyping in virtual teams can be of three distinct types: message-based, physical appearance/behavior-based, and technology-based. The development and validation of this instrument should enable future researchers to measure virtual team trust in a broad range of technology and team configurations.
Introduction of a Stress State Criterion to Predict Bond Strength between FRP and Concrete Substrate

To evaluate the performance of externally bonded fiber-reinforced polymer (FRP) composites to concrete structures, the bond strength is predicted at the maximum transferable load. Most of the existing prediction models neglect the adhesive material properties. As such, a previously proposed criterion on the FRP debonding initiation considering the adhesive material properties is extended by determining the fracture depth parameter and introducing a strength factor. The fracture depth represents a certain depth of a failure in concrete substrate and the strength factor revises the concrete tensile strength to be applied as the limit bond stress. Both the fracture depth parameter and strength factor are determined as a function of concrete compressive strength through experimental measurements and regression analysis, respectively. The proposed criterion is validated through the collected 342 experimental data points. Comparison between the predicted and the experiment results shows good agreement, providing a relatively high correlation factor. In addition, the predicted results are compared with existing prediction models.
The role of syntactic complexity in training wh- movement structures in agrammatic aphasia: Optimal order for promoting generalization

This study examined the postulate that training production of syntactically complex sentences results in generalization to less complex sentences that have processes in common with treated structures. Three agrammatic aphasic patients were trained to produce wh-movement structures, object clefts and/or object extracted who-questions, while generalization between these structures was tested. One NP-movement structure, passive sentences, also was tested for control purposes. Wh-movement occurs from the direct object position to specifier position in the complementizer phrase [SPEC, CP] for both wh-movement structures. In who-questions movement occurs in the matrix sentence, whereas, in object clefts movement occurs within an embedded relative clause, rendering them the most complex. Results showed robust generalization effects from object clefts to matrix who-question for 1 participant (D.L.); however, no generalization was noted from who-questions to object clefts for another (F.P.), and 1 participant (C.H.) showed acquisition of who-questions, but not object clefts, during the baseline condition without direct treatment. As expected, none of the participants showed improved production of passives. These findings supported those derived from our previous studies, indicating that generalization is enhanced not only when target structures are related along dimensions articulated by linguistic theory, but also when the direction of treatment is from more to less complex structures. The present findings also support proposals that projections of higher levels in the syntactic treatment are dependent on successful projection of lower levels. For our participants, training movement within CP in a lower (embedded) clause resulted in their ability to project to CP at higher levels.
Conversion of the N-O-glucuronide and N-O-sulfate conjugates of N-hydroxyphenacetin to reactive intermediates

Abstract The N-O-glucuronide of [14C]acetyl-N-hydroxyphenacetin is sufficiently stable to purify, but slowly breaks down in aqueous solutions to a reactive intermediate that can covalently bind to protein. When the pure compound was incubated in Tris buffer, pH 7.4, at 37°, it decomposed with a half-life of about 8.7 hr to the following compounds: phenacetin, 2-hydroxyphenacetin glucuronide, acetamide and acetaminophen. On addition of glulathione to the systems and allowing the reactions to go to completion, a glutathione-acetaminophen conjugate was formed at the expense of acetamide and acetaminophen: the fraction converted to phenacetin or to the 2-hydroxyphenacetin glucuronide was unchanged. On addition of ascorbic acid to the system and allowing the reactions to go to completion, the fraction converted to acetaminophen was increased at the expense of acetamide: the fractions converted to phenacetin and 2-hydroxyphenacetin glucuronide, however, were again unchanged. When the glucuronide was incubated with bovine serum albumin, covalent binding to the protein occurred at the expense of acetaminophen and acetamide; again, the fraction of the glucuronide converted to phenacetin and 2-hydroxyphenacetin glucuronide was unchanged. Moreover, the covalent binding could be partially prevented by addition of ascorbic acid or glutathione. Since there is formation of covalently bound material, the glutathione conjugate and acetaminophen appear to be interrelated; it seems likely that they are formed from a common intermediate, possibly acetylimidoquinone. However, the data suggest that the formation of phenacetin and 2-hydroxyphenacetin glucuronide occurs by different mechanisms. The N-O-sulfate of [14C]acetyl-N-hydroxyphenacetin also breaks down to a reactive intermediate that has properties similar to those of the reactive intermediate formed from the N-O-glucuronide and thus may also be N-acetylimidoquinone. By contrast, the relative ability of various nucleophiles to prevent the covalent binding of the reactive intermediate formed from the N-O-sulfate of 2-acetylaminofluorene to protein differs from the relative ability of the nucleophiles to prevent the covalent binding of the reactive intermediate of either the N-O-sulfate or the N-O-glucuronide of phenacetin, suggesting that the relative rates at which these intermediates combine with the different macromolecules may differ markedly.
Marywood Librarians Teach in Africa

Librarians Leslie Christianson and Julie Watson from Marywood University have been working to educate Catholic nuns in Africa. Funded by a grant from the Conrad N. Hilton Foundation, the Higher Education for Sisters in Africa (HESA) project is a partnership between Marywood University and Catholic University of Eastern Africa (CUEA) in Nairobi, Kenya.
Language heterogeneity and regression in the autism spectrum disorders—Overlaps with other childhood language regression syndromes

Abstract Some third of parents of children on the autism spectrum report that their toddler’s language regressed, usually insidiously, or stagnated during a prolonged plateau. Regression was associated with loss of sociability, interest in toys, and other behavioral skills, without motor regression. After months or longer, language usually returns, but variably severe autistic features persist. Nonverbal cognitive skills may or may not be affected. Some parents recall some antecedent nonspecific illness or stressor like the absence of a parent, a move, or the birth of a sibling. Occasionally, regression seems temporally related to an epileptic seizure, suggesting an overlap with acquired epileptic aphasia (Landau–Kleffner syndrome—LKS) in which language regression is associated with either clinical seizures or subclinical perisylvian temporo-parietal epileptiform EEG activity. LKS onset peaks at 4–6 years, autistic regression before age 2 years and is infrequently associated with seizures or an epileptiform EEG, except in the rare case of disintegrative disorder, a late global autistic regression which, like LKS, may be associated with electrical status epilepticus in slow wave sleep. Mute or dysfluent children with LKS, autism, or developmental language disorders are unable to decode or have difficulty decoding acoustically presented language (speech). They are at higher risk for epilepsy than fluent children with the typically aberrant language of verbal children with autism. The pathogenesis of language regression remains unknown because autistic toddlers are rarely studied at the time of language regression so that no empirically validated effective treatment has yet been devised.
Stannous ion quantitation in 99mTc-radiopharmaceutical kits.

A simple and inexpensive method for the estimation of stannous ion, Sn (II), in radiopharmaceutical kits is described. The method used is a potentiometric titration of Sn (II) in 1 N HCl medium, using potassium iodate as the oxidizing agent in an atmosphere of nitrogen. The apparatus includes a pH meter, a platinum electrode, and a simple titration cell. Several commonly used radiopharmaceutical kits were analyzed for their Sn (II) content using this method. These studies indicate that the procedure can be used, as a routine quantitative test for the Sn (II) content of various 99mTc-labeled radiopharmaceuticals.
THE RELATIONSHIP OF URINARY 17-HYDROXYCORTICOSTEROIDS TO CREATININE IN OBESITY.

Abstract The relationship of 4-hour urinary 17-hydroxycorticosteroids to creatinine levels was investigated in 18 obese and 16 nonobese college students while on controlled dietary intakes. The mean urinary creatinines were significantly higher in the obese than in the nonobese group (299 ± 79 mg. and 240 ± 87 mg., respectively). The mean urinary 17-OHCS levels also were significantly higher in the obese (1.21 ± 0.57 mg.) than in the nonobese group (0.72 ± 0.32 mg.). The relative ratios of 17-OHCS to creatinine did not differ significantly between the 2 groups but when the ratios were calculated on the basis of creatinine expressed per Kg. of body weight, the differences were highly significant (4.11 ± 1.80 vs. 1.89 ± 0.81 for the obese and nonobese, respectively). The data suggest that cortisol excretion, and by implication, cortisol production, may vary with changes in muscle mass. The data also suggest that the relative ratios of urinary 17-OHCS and creatinine may be of value in assessing the significance of 17-OHCS levels in the interpretation and diagnosis of obesity.
Mesencephalic enlarged Virchow–Robin spaces in a 6-year-old boy: a case-based update

Perivascular spaces or Virchow–Robin spaces are normal anatomical structures within the brain, typically less than 5 mm in diameter. Rarely, they can reach much larger sizes and adopt bizarre single or multi-cystic configurations, as was the case in the patient that we report on. When there is such markedly gross dilatation, the phenomenon is known as Giant or tumefactive perivascular space enlargement. We report a 6-year-old boy with a multi-cystic mesencephalic lesions presenting with obstructive hydrocephalus secondary to obstruction of the aqueduct of Sylvius due to tumefactive dilatation of Virchow–Robin spaces. The patient underwent an endoscopic fenestration and biopsy of the cystic portion abutting into the ventricular system. In this paper, we discuss the phenomenon of perivascular (Virchow–Robin) spaces and their treatment options and review the relevant literature. To our knowledge, this is the first pediatric case of tumefactive dilatation of the Virchow–Robin spaces causing obstructive hydrocephalus that were directly fenestrated using neuroendoscopy.
The efficacy of the drip method in the reduction of gastric acidity

1. The control of gastric acidity by intermittent methods especially during the night is discussed and attention is called to the inadequacy of such procedures in general use for ulcer therapy. 2. Drip therapy affords a method for thecontinuous neutralization, throughout the twenty-four hour cycle. 3. A quantitative study of the relative merits and efficiencies of milk-NaHCO3, aluminum hydroxide gel, and aluminum phosphate gel, is reported in a group of 38 cases of peptic ulcer. All three are found to be extremely effective antacids when administered by continuous drip. 4. Neither the milk-NaHCO3 nor the aluminum hydroxide gel was effective to any considerable degree in cases of pyloric obstruction.
Theory into practice

Genetics and Medicine in the United States, 1800-1922. By Alan R. Rushton. Johns Hopkins University Press: 1994. Pp. 209. $45, £37.
Sample preparation for total nitrogen and 15N‐ratio analysis by the automated Dumas combustion method

Abstract Dry combustion based on the Dumas (1831) method has become increasingly popular for total nitrogen (N) and isotope‐ratio analyses. However, the lack of sample homogeneity with soil and plant samples is often the limiting factor for the accuracy and precision of this method. Moreover, water samples are not directly analyzed by the Dumas method on a routine basis. The objective of this study was to develop an adequate sample preparation protocol for plant and water samples to be analyzed for their total N and 15N‐ratios by the Dumas method. Twenty‐four corn (Zea mays L.) samples were randomly selected, dried at 60°C, and finely ground. Plant samples were analyzed for total N by the traditional Kjeldahl and Dumas methods. Seven preparations of subsurface drainage and standard nitrate (NO3)‐N solution samples were similarly analyzed for their total N content. The effects of reducing agent (copper wire or shot) used on total N and 15N isotope ratios were also investigated in this study. The average pe...