cssi/SciSciGPT-SciSciNet huggingface dataset:
Motor cortical excitability in schizophrenia

Abstract Background: Transcranial magnetic stimulation (TMS) provides a method to examine cortico-cortical motor excitability and hemispheric asymmetry in unmedicated and medicated schizophrenia patients. Methods: Fourteen right-handed schizophrenia patients (seven on conventional neuroleptics and seven medication-free) were compared with seven right-handed, age- and gender-matched normal control subjects. Motor threshold for induction of motor-evoked potentials (MEPs) and bihemispheric intracortical inhibition and facilitation were measured with single-pulse and paired-pulse TMS. Results: Medicated patients showed an approximately 5% higher motor thresholds in both hemispheres than unmedicated patients and control subjects. Normal control subjects had a nearly 10% higher threshold for the left than the right hemisphere, whereas the opposite was true for the patient groups (5–10% higher threshold on the right than the left). Medicated patients showed significantly decreased intracortical inhibition relative to unmedicated patients and control subjects. This difference was more pronounced for the right than for the left hemisphere. Conclusions: Treatment with conventional neuroleptics is associated with increased motor threshold and decreased intracortical inhibition, whereas unmedicated patients did not differ from normal control subjects on these measures; however, schizophrenia may be characterized by a reversed pattern of interhemispheric corticospinal excitability.
Introduction to the open archives initiative protocol for metadata harvesting

The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) [1] is a relatively new interoperability standard that is gaining much attention from existing and new digital libraries. It is currently advocated by many communities (including NDLTD, NCSTRL, and NSDL) to fulfill their metadata interoperability requirements.This tutorial is aimed at introducing individuals to the concepts underlying the OAI and the harvesting protocol, as well as providing sufficient information to allow attendees to almost immediately implement the current standard (OAI-PMH v2.0) on their own archives or in their own communities. Attendees will be introduced to both organizational and technical issues that need to be addressed when building new systems or extending existing systems, either in the capacity of being providers of data, users of data, or both. Wherever appropriate, references will be made to best practices that have emerged in the community of OAI implementers since the initial release of the protocol. Attendees will also be familiarized with tools developed within the OAI community to support the implementation of the protocol.
Nonlinear implicit variational inequalities involving partially relaxed pseudomonotone mappings

Abstract Based on a class of generalized iterative algorithms, approximation-solvability of a class of nonlinear implicit variational inequalities involving partially relaxed pseudomonotone mappings—a mild generalization of the general notion of partial relaxed monotonicity—is discussed. The partial relaxed monotonicity itself is a widely studied and computation-oriented class and is more general than the notions of cocoercivity and strong monotonicity.
The Real World of Integrating Electronic Resources into a Web OPAC

Summary For the researcher, there has been an increase in the availability of electronic resources that includes electronic journals, databases and full-text resources. A Web OPAC is a powerful tool that links all of these electronic resources for easy access. Workshop presenters described their experience with establishing a Web OPAC and how systems, serials cataloging and reference dealt with it.
Artificial intelligence: Debates about its use and abuse

Abstract This paper is concerned with the question, “Is what a stored-program digital computer does thinking -in the full human sense of the term?” Several current controversies are examined, including the meaning and usefulness of the Turing test to determine “intelligence.” The Lucas controversy of the early 1960s is taken up, dealing with the philosophical issues related to the man-versus-machine debate, and Dreyfus' ideas against Machine Intelligence are explored. Searle's ideas in opposition to the validity of the Turing test are described, as are various interpretations of the Chinese room thought-experiment and its relation to real “thought”. Weizenbaum's opposition to the “information-processing model of man” is also developed. The paper concludes with a comparison of the 19th-century debates over Darwinian Evolution and those in this century over Artificial Intelligence.
Phosphorylation of the replication protein A large subunit in the Saccharomyces cerevisiae checkpoint response

The checkpoint mechanisms that delay cell cycle progression in response to DNA damage or inhibition of DNA replication are necessary for maintenance of genetic stability in eukaryotic cells. Potential targets of checkpoint-mediated regulation include proteins directly involved in DNA metabolism, such as the cellular single-stranded DNA (ssDNA) binding protein, replication protein A (RPA). Studies in Saccharomyces cerevisiae have revealed that the RPA large subunit (Rfa1p) is involved in the G1 and S phase DNA damage checkpoints. We now demonstrate that Rfa1p is phosphorylated in response to various forms of genotoxic stress, including radiation and hydroxyurea exposure, and further show that phosphorylation of Rfa1p is dependent on the central checkpoint regulator Mec1p. Analysis of the requirement for other checkpoint genes indicates that different mechanisms mediate radiation- and hydroxyurea-induced Rfa1p phosphorylation despite the common requirement for functional Mec1p. In addition, experiments with mutants defective in the Cdc13p telomere-binding protein indicate that ssDNA formation is an important signal for Rfa1p phosphorylation. Because Rfa1p contains the major ssDNA binding activity of the RPA heterotrimer and is required for DNA replication, repair and recombination, it is possible that phosphorylation of this subunit is directly involved in modulating RPA activity during the checkpoint response.
Thyroxine 5′-Deiodinase Activity in Pineal Gland and Frontal Cortex: Nighttime Increase and the Effect of Either Continuous Light Exposure or Superior Cervical Ganglionectomy*

Type II T4 5′-deiodinase (5′-D) activity was studied in pineal gland, frontal cortex, and anterior pituitary of male rats. Enzymatic activity was determined by the release of 125I using [3′,5′-125I]T4 as substrate. Daytime levels of 5′-D activity were maximal for anterior pituitary (346.2 ± 142.5 fmol 126I released/mg protein h), followed by pineal gland (61.5 ± 8.7 fmol 125I released/mg protein-h) and frontal cortex (3.1 ± 0.5 fmol 125I released/mg protein · h). Twenty-four-hour fluctuations of 5′-D activity were apparent in the pineal gland and cortex. For pineal, peak 5′-D activity (43.4 ± 11.4 fmol 125I released/gland h) occurred at 0100 h, with values at this time being 8-fold greater than basal daytime levels. Superior cervical ganglionectomy (SCGX) or exposure to continuous light (LL) completely abolished the nocturnal rise of 5′-D activity. Treatment with iopanoic acid also inhibited 5′-D activity in pineal (32.1 ± 3.5 vs. 18.8 ± 1.7 fmol 125I released/glandh) without influencing either the N-acet...
Statistical issues in health impact assessment at the state and local levels

In this work, we discuss the uncertainty in estimating the human health risk due to exposure to air pollution, including personal and population average exposure error, epidemiological designs, and methods of analysis. Different epidemiological models may lead to very different conclusions for the same set of data. Thus, evaluation of the assumptions made and sensitivity analysis are necessary. Short-term health impact indicators may be calculated using concentration–response (C-R) functions. We discuss different methods to combine C-R function estimates from a given locale and time period with the larger body of evidence from other locales and periods and with the literature. A shrunken method is recommended to combine C-R function estimates from multiple locales. This shrunken estimate includes information from the overall and the local estimates, and thus, it characterizes the estimated excess of risk due to heterogeneity between the different locations.
Pathogenic organisms associated with asthma in children treated in the intensive care unit

Although respiratory infections are not the major or only trigger of asthma, relationships between these infections and the development of acute and chronic asthma have been established. Exacerbations of acute asthma are a major cause of admission to the intensive care unit (ICU), and the contribution of respiratory viruses to severe exacerbations of asthma requiring intensive care is well established. The authors review the association of acute asthma requiring treatment in the ICU with viral (adenovirus, respiratory syncytial virus, rhinovirus, and other viruses), bacterial (Haemophilus influenza, Bordetella pertussis, Streptococcus pneumoniae, Pseudomonas, Staphylococcus, and Mycobacterium tuberculosis), fungal (Aspergillus fumugatis and Pneumonycystis carinii), and other infections and review management and treatment goals.
Veganism, Identity and the Quest for Authenticity

AbstractIdentifying as a vegan is a public declaration of one's identity, morals and lifestyle. Veganism is more than a diet; it is a philosophy and ethic. However, not all vegans hold the same norms and values. The differences are often determined by the reasons why one chooses to become a vegan. Using Coffman's theory of impression management and the presentation of self, this qualitative study examines how sixteen self-defined ethical vegans negotiate contradictions in their ethics and behavior. The vegans construct a sense of authenticity through accommodating strategies when they feel inauthentic. This is a two-prong process. They present a narrative of themselves in relation to the “other”-those they define as health vegans-and in relation to other ethical vegans. Through these narratives, this paper explores how these vegans negotiate the difficulties of living in an animal-based consumer-driven society in a manner that preserves their ethics. Additionally, this paper observes how they cope when th...
Effects of hypnosis and imagery training on naming behavior in aphasia

Abstract The effects of hypnosis and imagery training on the naming behavior of three subjects with Broca's aphasia were investigated using a multiple baseline design across subjects. Treatment consisted of the induction of hypnosis, followed by guided imagery focused on the physical and functional attributes of stimulus objects. Measures of naming ability on both trained and untrained items were taken at baseline, after every training session, and a few hours after training each day. Measures were also taken of imagery ability, hypnotic susceptibility, and psychological state. Results indicated that treatment facilitated improvement in naming ability, over baseline level, for two subjects. In the case of the third subject, the verbal label was incorporated into the imagery procedure following 10 training sessions. Subsequently, this subject's naming behavior improved over baseline level. The results are discussed in terms of current theory and research in neuropsychology and cognitive psychology.
EFFECT OF PRESSURE ON CULTURED SMOOTH MUSCLE CELLS

Recent studies indicate that smooth muscle cell (SMC) growth and morphology can be modulated by repetitive strain. However, there is very little known about the influence of pressure, without an associated cell stretch, on SMC phenotype. To study this, cultured bovine aortic SMC were grown on a rigid surface and placed in a custom-designed plexiglass pressure chamber with a carefully regulated 5% CO2/air environment. SMC were exposed to either atmospheric, 105 mm Hg or 120/90 mm Hg pressure at a frequency of 60 cycles/min (0.5 s systole, 0.5 s diastole). SMC number was determined on days 1, 3, 5, 7 and 9. SMC exposed to pressure were more elongated and displayed a significant increase in cell number by day 5 which persisted until day 9. Lactate dehydrogenase (LDH) in the conditioned media, an index of cytotoxicity, was not different between the groups at each time point. There was also no difference in pH or pCO2 of the media of SMC in any group. This is the first report of the effects of increased static and pulsatile pressure on SMC in vitro and indicates an increased proliferative rate. We hypothesize that the systemic pressure that the blood vessel is exposed to in vivo may have a significant regulatory influence on the phenotype of the smooth muscle cells which may affect the SMC response to injury or stimuli.
Differential compaction in lithified deep-sea sediments is not evidence for ``diagenetic unmixing''

Abstract The process of diagenetic unmixing, by which calcium carbonate might be transferred between sediment layers at burial depths of hundreds of meters to kilometers, has been proposed to account for the origin of alternating limestones and marls in lithified pelagic sequences. A quantitative model for estimating the amount of transfer of carbonate developed by Ricken (1986) depends on differential compaction estimates inferred from varying degrees of burrow flattening in limestones and marls. However, a review of physical property and calcium carbonate data compiled by deep-sea drilling shows that a key assumption in Ricken's model is incorrect. Pelagic sediments exhibit large variations in initial porosity that depend negatively on carbonate content. Differential compaction in lithified sections is thus expected from primary porosity variations that follow carbonate content. Furthermore, no analogue to the diagenetic unmixing process has been observed in long deep-sea sections logged for density and porosity.
Protamine sulfate-induced cystitis: a model of selective cytodestruction of the urothelium.

monary fibrosis. Because mast cell enzymes have been implicated in the fibrotic response, we sought to examine the possible regulatory role of mast cells in bladder wall fibrosis. Hence, the objectives of this study were to determine if there was an increase in inflammatory mast cell number and location in bladder wall tissue from myelodysplasia patients, and to determine if the mast cell proteases, chymase and tryptase, could alter connective tissue expression in bladder wall cells. Transmural tissue sections from human control (n 5 5) and myelodysplastic (n 5 7) bladders were stained with mast cell–specific serine protease antibodies (antitryptase, antichymase) to determine the number, location, and state of degranulation of mast cells. Human bladder lamina propria fibroblasts and detrusor smooth muscle cells were isolated from control tissue collagenase digestion, treated in vitro with recombinant chymase and tryptase, and analyzed by enzyme-linked immunosorbent assay for alterations in extracellular matrix proteins (collagens I and III, and elastin). Bladders from myelomeningocele patients were characterized by increased numbers of mast cells within detrusor muscle bundles infiltrated with connective tissue. Regions of detrusor muscle adjacent to the lamina propria showed evidence of mast cell degranulation and increased connective tissue deposition. Tryptase treatment resulted in a decrease in both type III collagen and elastin in both fibroblasts and smooth muscle cells. In contrast, chymase treatment resulted in an increase in both type III and elastin. Expression of type I collagen was variable depending on the cell type treated and the specific enzyme. Denaturation of the enzymes by heat treatment resulted in a return to control levels. These studies show that bladder fibrosis may be mediated, in part, by mast cell products altering the connective tissue milieu of the bladder wall.
Moving forward in Sierra Leone: community-based factors for postconflict development

War and conflict, while not manifested as economic or natural disaster, often bring the same consequences and damages and require similar capacity building. This article discusses the following fou...
Entropy of nonextreme charged rotating black holes in string theory.

We give the explicit expression for four-dimensional rotating charged black hole solutions of $N=4$ (or $N=8$) superstring vacua, parametrized by the ADM mass, four charges [two electric and two magnetic charges, each arising from a different U(1) gauge factor], and the angular momentum (as well as the asymptotic values of four toroidal moduli of a two-torus and the dilaton-axion field). The explicit form of the thermodynamic entropy is parametrized in a suggestive way as a sum of the product of the "left-moving" and the "right-moving" terms, which may have an interpretation in terms of the microscopic degrees of freedom of the corresponding $D$-brane configuration. We also give an analogous parametrization of the thermodynamic entropy for the recently obtained five-dimensional rotating charged black holes parametrized by the ADM mass, three U(1) charges, and two rotational parameters (as well as the asymptotic values of one toroidal modulus and the dilaton).
Endobronchial Mycobacterium avium-intracellulare Infection in a Patient with AIDS*

The pulmonary manifestations of AIDS are well described in the medical literature; however, MAI infection presenting as an endobronchial lesion has not, to our knowledge, been reported in a patient with AIDS. We report a unique case of an AIDS patient who developed endobronchial polypoid lesions secondary to MAI infection. Complications resulting from these lesions included hemoptysis and later bronchiectasis.
Mapping impulse propagation in the heart: an approach to the study of arrhythmogenesis.

A recording system is described which enables extracellular electrical activity from a large number of sites on thein situ heart to be registered simultaneously. The usefulness of this approach for the study of arrhythmogenesis is discussed.
New anatomical aspects of the vasculo-epithelial zone of the spiral limbus in mammals. An electron microscopic study.

The ultrastructure of the vasculo-epithelial zone of the spiral limbus of the guinea pig and cat is described. The vasculo-epithelial zone is composed of two types of cells osmiophilic (dark) and osmio-phobic (light) cells. The osmiophilic cells line the surface of the vasculo-epithelial zone and are bathed in perilymph. These cells have a dense cytoplasm and consist of numerous plasma membrane processes which are filled with tightly-packed mitochondria. Other cellular inclusions comprise an extensive network of endoplasmic reticulum and Golgi apparatus. The inferior layer consists of osmiophobic cells which contain endoplasmic reticulum and mitochondria. Morphologic similarities were noted among the vasculo-epithelial zone and other areas of the inner ear which are capable of active transport, e.g. the mammalian vestibular dark cells and the stria vascularis. The ultrastructural characteristics of the vasculo-epithelial zone suggest that this site is capable of active transport.
Characterization of the basal and carcinogen regulatory elements of the rat mdr1b promoter

In this report we characterized the transcriptional regulation of the rat mdr1b gene by xenobiotics. The expression of this gene was increased in primary rat hepatocytes and in the H4-II-E hepatoma cell line by exposure to carcinogens such as aflatoxin B1, N-acetoxy-2-acetylaminofluorene, and methyl methanesulfonate. Nuclear run-on experiments indicated that the higher steady-state levels of mdr1b mRNA were due to an increase in transcription. The 5′-flanking region of the mdr1b gene was isolated, sequenced, and functionally characterized in transient and stable transfection assays. A single transcription start site was identified for this gene; no alternate start sites were used after induction with aflatoxin B1. Deletion analysis of this promoter demonstrated that the sequence between nt −214 and −178 was critical for basal promoter activity. This region did not contain any consensus-binding sites for previously identified transcription factors. A negative regulatory region was also identified between nt −940 and −250. No specific carcinogen-responsive element was identified; the xenobiotic response required a large part of the promoter. These data suggest that the carcinogen induction of mdr1b expression is mediated through sequences that overlap or that are identical to the basal promoter element. © 1995 Wiley-Liss, Inc.
UK planning: the state of the library

Abstract Bookwatch will be a regular feature of Cities. It will suplement the book review section by providing a broad survey of other books. Sometimes a particular theme will be chosen or a commentary will be given on some interesting trend. Alternatively there might be a discussion of books which have not been written but which ought to be. In this first issue the Bookwatch focus is on the Nuffield Foundation's inquiry into the UK system of town and country planning, and on some recent books which should prove useful to the committee.
The Future of Clinical Pharmacy: Developing a Holistic Model

This concept paper discusses the untapped promise of often overlooked humanistic skills to advance the practice of pharmacy. It highlights the seminal work that is, increasingly, integrated into medical and nursing education. The work of these educators and the growing empirical evidence that validates the importance of humanistic skills is raising questions for the future of pharmacy education and practice. To potentiate humanistic professional competencies, e.g., compassion, empathy, and emotional intelligence, how do we develop a more holistic model that integrates reflective and affective skills? There are many historical and current transitions in the profession and practice of pharmacy. If our education model is refocused with an emphasis on pharmacy’s therapeutic roots, the field has the opportunity to play a vital role in improving health outcomes and patient-centered care. Beyond the metrics of treatment effects, achieving greater patient-centeredness will require transformations that improve care processes and invest in patients’ experiences of the treatment and care they receive. Is layering on additional science sufficient to yield better health outcomes if we neglect the power of empathic interactions in the healing process?
Molecular biology of preimplantation embryos: primer for philosophical discussions

This article is based on a presentation at the First International Conference on Ethics, Science and Moral Philosophy of Assisted Human Reproduction. The goal is to provide scientific background for the discussion of philosophic issues. Recent advances in the systematic molecular analysis of preimplantation embryos are summarized, including the molecular identification of nearly all genes involved in preimplantation development and their detailed expression patterns. Notwithstanding a quantum leap in molecular understanding of preimplantation embryos, molecular evidence seems to provide no decisive definition of a threshold for the beginning of human life during preimplantation development.
Cigarette Smoke: Charcoal Filters Reduce Components That Inhibit Growth of Cultured Human Cells

Water-soluble components of total cigarette smoke inhibit cell growth and protein synthesis by the KB line of human cells. The cytotoxic components were in both the gas phase and the particulate phase of smoke. Conventional filters of cellulose acetate reduced cytotoxicity of the particulate phase in proportion to the weight of particles trapped, that is, they did not alter the specific activity of the particulate phase. Appropriately designed filters containing activated charcoal granules selectively reduced cytotoxic components in cigarette smoke which would have appeared in both phases, although the reduction, as anticipated, occurred to a greater extent in the gas phase.
Changes in nutritional status and patterns of morbidity among free-living elderly persons: A 10-year longitudinal study☆

Abstract Nutritional intake appears to be an important factor contributing to aging. In the present study we describe changes in physical health related to nutritional intake among elderly persons in a 10-y longitudinal study. Among 304 healthy elderly participants (median age 72 y on entry into the study in 1980), 97 (34.2%) are still in good health 10 y later in 1990, 74 (26.5%) have become frail or sick, 54 (19.1%) have died, and 57 (20.1%) have dropped out of the study. Women with lower or higher energy intakes (in 1980 and 1981) than the current Recommended Daily Allowance (RDA; between 25 and 30 kcal/kg) were more likely to become frail or sick or to die in 1990 than those with energy intake in the midrange (below RDA, odds ratio (OR) = 3.3, confidence interval (CI) = 1.2–8.6; above RDA, OR = 3.4, CI: 1.1–10.7). Moreover, women with protein intakes greater than the midrange of 0.8–1.2 g/kg of body weight (1.20–1.76 g/kg in 1980 and 1981) tended to have fewer health problems over the next 10 y than those with protein intakes
Overcoming Stigma: Credit for Self-Improvement or Discredit for Needing to Improve?

In Experiment 1, subjects rated the likelihood that an individual would follow up socially with each of two persons, one of whom had overcome a stigma by his or her own efforts. Persons with a history of stigma who were currently as desirable as the comparison person were subject to the same social deficit as if they were less desirable; only if persons with a history of stigma were currently more desirable than the comparison person were they equally preferred as dates. A second experiment indicated that the "once flawed" effect applies to objects as well as to persons. A third experiment that broke down positive evaluation into the two dimensions of respect/admiration and "wanting to be with" found that people admire those who have overcome a stigma by their own efforts but would rather be with those who never had a stigma.
Trading "wet-work" for network.

A computational model of tyrosine receptor kinase signaling simulates a complex network containing 94 components.
Thailand's Destination Image through the Eyes of Its Citizens

This study investigates images of Thailand from the perspectives of Thai residents. The study was conducted at domestic and international tourist destinations in Southern Thailand, and 352 respondents participated in the study. The majority of respondents were females, 18–34 years old, and single. Residents from both destinations ranked natural beauty as Thailand's most important image. A significant difference was found in residents' perceptions of images of Thailand. These included activities and topics such as hiking and sightseeing, variety of food, spas and massages, night life, entertainment, night clubs and bars, relaxing and calm setting, a good place for a family to visit, and signs in other languages.
Thyroidal and prolactin secretion in agalactic mares.

A study was designed to examine serum concentrations of prolactin (PRL) and iodothyronines before and after thyrotropin releasing hormone (TRH) administration to agalactic (n = 26) and normally (n = 8) lactating mares. Two mg TRH was given intramuscularly (i.m.) twice daily on Day 1 (day of delivery) through Day 5. Jugular venous blood was collected on Days 1 and 5 before TRH (time 0) and at 1 and 3 h post-TRH. Basal serum concentrations of thyroxin (T4) were different (P < 0.05) on Day 1 (1.87 vs 1.37 μg/dl) and Day 5 (1.72 vs 1.13 μg/dl) in the normal mares and agalactic mares, respectively. There was no difference in the T4 response to TRH. While basal serum concentrations of triiodothyronine (T3) were not different, agalactic mares responded with greater (P < 0.05) serum concentrations T3 to TRH on Day 1. Following linear regression of the PRL response to TRH, slope of the lines between groups did not differ; however, elevations were significantly (P < 0.05) greater (1.79 vs 1.28 ng/ml) in control mares compared with agalactic mares, respectively, on Day 1·at 1 h post-TRH. A similar difference existed at time 0 and 1 h on Day 5. Consequently, agalactic mares had reduced basal serum T4 values; the PRL data leads us to suggest that secretion of this hormone may be insufficient in agalactic mares.
Active learning for large-scale factor analysis

A method for Bayesian factor analysis (FA) of large matrices is proposed. It is assumed that a small number of matrix elements are initially observed, and the statistical FA model is employed to actively and sequentially select which new matrix entries would be most informative, in order to estimate the remaining missing entries, i.e., complete the matrix. The model inference and active learning are performed within an online variational Bayes (VB) framework. A fast and provably near-optimal greedy algorithm is used to sequentially maximize the mutual information contribution from new observations, taking advantage of submodularity properties. Additionally, a simple alternative procedure is proposed, in which the posterior parameters learned by the Bayesian approach are directly used. This alternative procedure is shown to achieve slightly higher prediction error, but requires much fewer computational resources. The methods are demonstrated on a very large matrix factorization problem, namely the Yahoo! Music ratings dataset.
Clinical Success of Complex Biological Therapies: Be Careful What You Wish For...

Would-be gene and cell therapists have longed for the day when they could escape the sneer that their field was 5 years from success—and has been that way for 20 years. Fortunately, our wish has been granted, for an increasing number of reports of clinical success in genetic diseases and cancer are appearing in high-profile journals and are being widely acknowledged. But now that this first stage has passed, we are left with what is in many ways a more intractable problem. How do we ensure that safe and effective complex biological therapies (CBTs) become licensed products that are sufficiently viable from a commercial standpoint to be widely distributed as the standard of clinical practice? In a series of articles over the coming year, Molecular Therapy will examine these issues in more detail, but I will begin by outlining the problem here.
Partial Oxidation of Propylene Catalyzed by VO3 Clusters: A Density Functional Theory Study

Density functional theory (DFT) calculations are carried out to investigate partial oxidation of propylene over neutral VO 3 clusters. C=C bond cleavage products CH 3CHO + VO 2CH 2 and HCHO + VO 2CHCH 3 can be formed overall barrierlessly from the reaction of propylene with VO 3 at room temperature. Formation of hydrogen transfer products H 2O + VO 2C 3H 4, CH 2=CHCHO + VO 2H 2, CH 3CH 2CHO + VO 2, and (CH 3) 2CO + VO 2 is subject to tiny (0.01 eV) or small (0.06 eV, 0.19 eV) overall free energy barriers, although their formation is thermodynamically more favorable than the formation of C=C bond cleavage products. These DFT results are in agreement with recent experimental observations. VO 3 regeneration processes at room temperature are also investigated through reaction of O 2 with the CC bond cleavage products VO 2CH 2 and VO 2CHCH 3. The following barrierless reaction channels are identified: VO 2CH 2 + O 2 --> VO 3 + CH 2O; VO 2CH 2 + O 2 --> VO 3C + H 2O, VO 3C + O 2 --> VO 3 + CO 2; VO 2CHCH 3 + O 2 --> VO 3 + CH 3CHO; and VO 2CHCH 3 + O 2 --> VO 3C + CH 3OH, VO 3C + O 2 --> VO 3 + CO 2. The kinetically most favorable reaction products are CH 3CHO, H 2O, and CO 2 in the gas phase model catalytic cycles. The results parallel similar behavior in the selective oxidation of propylene over condensed phase V 2O 5/SiO 2 catalysts.
Higher-order effects in hopping-type transport of small polarons. II. Quantal occurrence-probability treatment

Abstract In the present paper, the higher-order corrections to the standard expression for the hopping rate of small polarons, obtained in the preceding paper, are here derived within the framework of the recently developed quantal occurrence-probability formulation of hopping-type transport. It is shown that the relative importance of the higher-order corrections is considerably enhanced when the vibrational spectrum of the host crystal is characterized by weak dispersion. The role of ultraweak dispersion for both two-site and multisite “correlated” hopping is discussed.
Effect of 17β-estradiol on mRNA expression of large-conductance, voltage-dependent, and calcium-activated potassium channel α and β subunits in guinea pig

Large-conductance, voltage- and calcium-activated potassium (MaxiK) channels play a key role in cell excitability. MaxiK channels are composed of a pore-forming α-subunit and a regulatory β-subunit, of which four (β1–4) genes have been identified. Previous findings suggested that MaxiK channel activity is regulated by estradiol. However, the underlying mechanisms have remained incompletely documented. Therefore, we used reverse transcriptase polymerase chain reaction to clone four cDNA fragments that were specific to the guinea pig α, β1, β2, and β4 genes. Using a sensitive ribonuclease protection assay, we found that the α and β4 mRNAs were the most abundant mRNAs in the brain and pituitary, whereas in the aorta, the α-subunit was coexpressed with the β1-subunit. Moreover, there was a significant upregulation of the α- but not the β1-subunit mRNA and the α-subunit protein in the aorta of the estrogen-vs oil-treated ovariectomized animals. In specific brain areas including preoptic area, ventral hypothalamus, hippocampus, and amygdala, and in the pituitary, neither the α- nor β4-subunit mRNAs were affected by estrogen. These findings suggest that estrogen may not affect the mRNA expression of MaxiK channels in the brain and pituitary. However, estrogen causes increased expression of MaxiK α in the aorta, which may explain some of the cardioprotective effects of estrogen in women.
Incorporation of impurities into macromolecular crystals

The chemical, mechanical and diffraction properties of crystals grown from solution, as well as their growth kinetics and morphological development, depend very much on the types and concentrations of impurities present in their mother liquor. The situation appears vastly more complicated in the case of macromolecular crystals because of the complex nature of the molecules and the biochemical milieu from which they are derived. An attempt is made here to catalog and characterize these various impurities. One class of impurities, large foreign particles (such as dust), microcrystals, misoriented three-dimensional nuclei, and large molecular clusters has been investigated in detail using atomic force microscopy. With this technique we have directly visualized the incorporation of such larger impurities and have delineated some of their more striking consequences. In particular we have found that in some cases such incorporation is accompanied by visible defect formation or dislocations. In other cases of small three-dimensional nuclei, coalescence proceeds in a smooth manner, with alignment and knitting together of the respective lattices. A calculation of the overall defect density in canavalin crystals shows the number of defects to be many orders of magnitude greater than found for most conventional crystals.
Crystal structure of tribasic lead sulfate (3PbO . PbSO4 . H2O) by X-rays and neutrons : An intermediate phase in the production of lead acid batteries

Abstract The crystal structure of tribasic lead sulfate (3PbO·PbSO 4 ·H 2 O) has been determined by a combination of single crystal X-ray and powder neutron diffraction to R of 0.024. From X-ray data, the space group is P 1 , a =6.378(1), b =7.454(2), c =10.308(2) A, α =75.26(3), β =79.37(3), γ =88.16(3)°. The structure can be represented with two types of layers: (i) hexagonal nets of Pb and (ii) similar layers but with 1/2 of Pb replaced by equal numbers of S and 2H. These layers are stacked in the sequence ...BAABAA... Structural units can be identified in tetragonal and orthorhombic PbO which are also present in tribasic lead sulfate and provide a common basis for relating these structures. These units are defined by Pb–O bonds which are less than 2.5 A which represent the strongest linkages. Two OH groups form weak hydrogen bonds to a single oxygen of a sulfate group. Lead polyhedra show both a range in coordination and Pb–O distances consistent with oxygen forming irregular polyhedra within the more regular cation framework. An alternative formula, 4PbO·H 2 SO 4 , may better represent the structure with the suggestion that H 2 and SO 4 groups replace Pb rather than the incorporation of H 2 O groups.
Enumeration of Heterotrophic microprotozoa by epifluorescence microscopy

The fluorochrome fluorescein isothiocyanate (FITC) binds to the amino groups of protein, and when used with epifluorescence microscopy provides a clear image of formalin preserved nanoplankton cells filtered from natural waters. The red autofluorescence of chlorophyll is not masked by the green fluorescence of FITC, so that autotrophic and heterotrophic plankton can be distinguished. The FITC direct count method can be used to determine in situ population size and growth rates of heterotrophic microprotozoa in aquatic systems. In Georgia estuarine and nearshore waters, we found between 0·3 × 103 and 4 × 103 colorless microprotozoa ml−1; most of the cells were less than 5 μm diameter. Rates of population increase measured at two estuarine sites corresponded to biomass production rates of 0·3 and 0·5 mg protozoan C m−3 h−1.
The Voltage Transformation Behavior in Unloaded Piezoelectric Transformers

The voltage transformation behavior is obtained at unloaded condition in the piezoelect- ric transformers (PTs) for two different designs. One design involves disk-type (cylindrical shape) single-layer (piece) piezoelectric material, and another design involves two-layer rectangular-type piezoelectric materials. Each of these piezoelectric transformers possesses three terminals of which one terminal being common between the input pair of terminals and the output pair of terminals. The cylindrical disk-type PT is unipoled and designed with varying geometry of the electrode areas used as input and output terminals. The rectangular-type PT consists of two piezoelectric layers having each layer separately poled and designed with uniform thickness and rectangular electrode area. The disk PT has a ring electrode area (A R ) and a dot electrode area (A D ) on the same face used as input and output terminals. The common terminal has a full-face electrode on the opposite face. The ratio of the output dot electrode...
Development of sleep spindles in the first year of life.

Spindles develop in man at 6 weeks conceptional age, at first at a low amplitude, gradually increasing in amplitude but especially in duration to a maximum at 13 weeks (mean, 6 sec ; longest, 21 sec), rapidly decreasing in duration with age to 23 weeks (mean, 2.5 sec) and then slowly decreasing to the end of the first year (mean, 1.5 sec). The pause between the spindles is usually inversely related to the spindle duration and stabilizes after 23 weeks at 7 sec. The complex of spindle and pause is the longest at 10 weeks (12.5 sec), decreasing with age and stabilizing at 17 weeks at 8.1 sec. Thus, from 17 weeks until the end of the first year, spindles tend to recur every 8-9 sec, although variability is evident, especially in the duration of the pause. Synchronous spindles develop from a low value of 10% to around a 30% value until the end of the year, and asynchronous ones tend to have the same value (30%) for most of the year, except in the youngest patients. The reticular nucleus of the thalamus is known to be the generator of spindles and an increase in soma size may be related to the great increase in duration, peaking at 13 weeks, and an increase in the development of the dendritic tree of this nucleus may be related to the many changes that stabilize at 23 weeks of age.
Auto‐oxidation of linoleic acid in micellar solution

The rates of auto-oxidation of different concentrations of linoleic acid, solubilized in various aqueous solutions of Brij 35, a nonionic surfactant, at 39.6° have been determined as a function of the changes in the spectrophotometric absorbance at 233 mμ which arises from the formation of conjugated diene as the process of auto-oxidation proceeds. For any one surfactant concentration over the range of linoleic acid concentrations studied, the maximum rate of conjugated diene formation (equivalent to the rate of oxidation in the initial stages of the reaction) was found to be directly proportional to the initial micellar concentration of linoleic acid, expressed as the weight ratio of linoleic acid to surfactant. As the concentration of surfactant was increased, the change in the maximum rate, as a function of the weight ratio of linoleic acid to surfactant, decreased. These results are discussed in the light of previous work dealing with the auto-oxidation of solubilized oils.
Quality of life measurement in the palliative management of advanced cancer

A 4-week quality of life (QOL) study was conducted in 157 consecutive advanced cancer patients to compare five QOL measures and to assess changes in QOL during the course of the study. The study patients were representative of the advanced cancer population in the USA, and were similar to the advanced cancer population with respect to age and gender. Global QOL measures appear to be as effective as multidimensional measures in assessing QOL in patients with advanced cancer. Generally, QOL was rated as satisfactory and did not change markedly during the study period.
Interactive software for PCs on composite micromechanics

Abstract A DCOMP software system is developed for calculating a set of composite effective properties from the properties of components and micromechanical parameters. Effective properties of particulate composites, fibrous composites and laminates made from these plies are predicted by the software. Particulate composites containing solid, hollow, encapsulated particles and pores are included in the software. The effect of particle aggregation is also incorporated. Fibrous composites with unidirectional, random inplane or random volume orientation of continuous or short fibres are calculated. Various hybrids can be analysed using multistage calculation. The following set of properties is computed: elastic constants, thermal and moisture expansion coefficients, transport characteristics, dynamic moduli and loss tangents, creep functions, density and specific constants. Classical lamination theory and well-known methods for fibrous composite analysis are utilized in the system. In addition, methods for particulate calculation developed by the author are included. The software consists of the library of computational programs, a user's developed database on material properties and service programs combined with a user-friendly interface. The last has a hierarchical menu system for data flow monitoring, an extensive window system for information display and data entry templates for the user formatted input collection. The software is written in the C language for IBM PCs and compatibles. Executable code requires 190K RAM. The capabilities of the system are illustrated by examples.
Optical coherence tomography in optic disk pit maculopathy treated by the macular buckling procedure.

Abstract PURPOSE: To report optical coherence tomography in optic disk pit maculopathy treated with macular scleral buckling procedure. METHODS: Twenty six eyes (26 patients) with optic disk pit maculopathy were treated with macular buckling procedure and evaluated with optical coherence tomography. In group 1, five eyes were evaluated with optical coherence tomography before and after macular buckling procedure. In group 2, 21 eyes were evaluated with optical coherence tomography after macular buckling procedure. With optical coherence tomography, cross-sectional, horizontal retinal images were obtained through the fovea and optic disk pit. RESULTS: In group 1, four of five eyes showed absorption of intraretinal fluid 7 to 9 months after macular buckling procedure. After absorption of fluid, retinal thickness in the foveal center ranged from 128 to 178 μm. In one eye the channel from optic disk to fovea reopened and fluid reappeared. In group 2, 20 of 21 eyes showed absorption of intraretinal schisis and subretinal fluid after macular buckling procedure. After absorption of fluid, retinal thickness in the foveal center ranged from 119 to 216 μm. CONCLUSIONS: In optic disk pit maculopathy, optical coherence tomography enabled morphologic assessment of the retina before and after macular buckling procedure. In the successfully treated cases the permanent closure of the connection between the optic disk pit and the intraretinal schisis was demonstrated. Eventual disappearance of schisis and subretinal fluid was depicted. It was also proved that the thickness of the macula returned to normal and visual acuity improved.
Complementary and alternative medicine for gastroparesis

Complementary and alternative medicine is of great interest to patients with gastrointestinal disorders and some will choose to ask their health care providers about those therapies for which some scientific evidence exists. This review focuses on those therapies most commonly used by patients, namely acupuncture/electroacupuncture and various herbal formulations that have been the focus of clinical and laboratory investigation. A discussion of their possible mechanisms of action and the results of clinical studies are summarized.
Computer-aided design of catalytic monoliths for automobile emission control

Abstract Automotive exhaust emission control catalysts are now in widespread commercial use in the U.S. and Japan, with rapid growth in Europe. The majority of these catalysts is of the monolith type. There is an ongoing interest in improving the durability performance of these catalysts in the presence of poisons. This paper describes the use of mathematical modeling as a tool for the design and optimization of monolith-type catalysts. The model has been used together with an optimization procedure to maximize the steady-state diffusion-controlled catalytic performance of a monolith-type catalyst after 1000 h of operation in the presence of poisons. The algorithm predicts optimum values of several important catalyst design variables (including washcoat thickness and pore structure) and monolith physical properties (such as channel size, wall thickness, and overall aspect ratio). Experimental data are presented for three-way monolith catalysts prepared with washcoats of differing pore structure and aged in the presence of typical exhaust poisons. The model properly ranks the observed differences in poison resistance for these washcoats and demonstrates its utility as a tool in the development of improved catalysts.
A novel early effect of concanavalin A on thymocytes.

Abstract Concanavalin A, added to freshly isolated rabbit thymocytes, markedly enhanced the extracellular appearance of non-immunoglobulin proteins. Time course studies revealed that the onset of enhancement occurred virtually without delay. The effect appeared to be restricted only to certain of the thymus-derived cells because thymocytes obtained from rabbits treated with hydrocortisone, as well as splenocytes derived from untreated rabbits essentially did not exhibit the enhancement. Stimulation by concanavalin A was specific in that pokeweed mitogen and lipopolysaccharide were without effect and also in that α-methyl-mannoside, but not galactose, abrogated the concanavalin A-mediated enhancement. Experiments with mouse thymocytes demonstrated that the cells which responded to concanavalin A were primarily cells that bear the θ-antigen on their surface (T-cells).