cssi/SciSciGPT-SciSciNet huggingface dataset:
Distribution and functional significance of the P-type, voltage-dependent Ca2+ channels in the mammalian central nervous system

Abstract In addition to the three types of voltage-dependent calcium channels presently recognized in the CNS, the L-, the T- and the N-types, a fourth distinct type known as the P-type channel has recently been described. This channel, initially recognized in Purkinje cells (and thus the name), is not blocked by dihydropyridines or by ω-conotoxin (GVIA), but is blocked by native funnelweb spider venom and by a polyamine (FTX) extracted from such venom. In addition, a synthetic polyamine (sFTX) has been produced that also specifically blocks P-channels in brain slices and at the neuromuscular junction, and blocks presynaptic Ca 2+ currents in other vertebrate and invertebrate forms, as well as channels expressed in Xenopus oocytes following CNS mRNA injections. Using sFTX to form an affinity gel, a protein was isolated and reconstituted into lipid bilayers where it manifests single-channel properties that are electrophysiologically and pharmacologically similar to those of the native P-channels. Rabbits immunized with the isolated protein produced a polyclonal antibody that gave a positive western blot with the purified P-channel protein and generated a reaction product at specific sites in the CNS that agree with the physiological distribution of P-channel activity.
A guide to electron paramagnetic resonance spectroscopy of Photosystem II membranes

This guide is intended to aid in the detection and identification of paramagnetic species in Photosystem II membranes, by electron paramagnetic resonance spectroscopy. The spectral features and occurrence of each of the electron paramagnetic resonance signals from Photosystem II are discussed, in relation to the nature of the moiety giving rise to the signal and the role of that species in photosynthetic electron transport. Examples of most of the signals discussed are shown. The electron paramagnetic resonance signals produced by the cytochrome b6f and Photosystem I complexes, as well as the signals from other common contaminants, are also reviewed. Furthermore, references to seminal experiments on bacterial reaction centers are included. By reviewing both the spectroscopic and biochemical bases for the electron paramagnetic resonance signals of the cofactors that mediate photosynthetic electron transport, this paper provides an introduction to the use and interpretation of electron paramagnetic resonance spectroscopy in the study of Photosystem II.
Unique cyanide nitrogen-15 nuclear magnetic resonance chemical shift values for cyano-peroxidase complexes. Relevance to the heme active-site structure and mechanism of peroxide activation

Abstract Cyanide ion has been utilized to probe the heme environment of the ferric states of horseradish peroxidase, lactoperoxidase and chloroperoxidase. The 15 N-NMR signal for cyanide bound to these enzymes is located in the downfield region from 578 to 412 ppm (with respect to the nitrate ion reference). The corresponding signal for met-forms of hemoglobin, myoglobin and cytochrome c is much further downfield in the 1047-847 ppm region. The signal position for peroxidases is quite invariant with pH in the physiological ranges. The upfield bias for peroxidase chemical shifts must reflect unique trans iron(III) ligand types and/or proximal-group hydrogen bonding or steric effects. Model compound studies reveal a significant upfield cyanide 15 N shift with addition of agents capable of hydrogen-bonding to the coordinated cyanide ion. An even more striking upfield shift of 277 ppm is associated with deprotonation of a trans imidazole residue. The distinctive chemical shifts observed for the cyano ligand in peroxidases support the hypothesis that a distal hydrogen-bonding network and perhaps a polar, basic trans ligand are essential for OO bond activation by peroxidases.
A New Solvent-Dependent Mechanism for a Triazolinedione Ene Reaction

The ene reaction between 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) and tetramethylethylene has been investigated using QM/MM calculations in water, methanol, DMSO, and acetonitrile. The effects of solvation on the mechanism and rates of reaction are elucidated using two-dimensional potentials of mean force (PMF) simulations utilizing free-energy perturbation theory and Monte Carlo statistical mechanics. A new mechanism is proposed where direct formation of an open dipolar intermediate following the addition of PTAD to the alkene is rate-limiting and the pathway toward ene product is significantly dependent on the reaction medium. In protic solvents, the open dipolar intermediate may proceed directly to the ene product or reversibly form an aziridinium imide (AI) intermediate that does not participate in the reaction. However, in aprotic solvents the open intermediate is short-lived (<10-11 s) and the ene product forms via the AI intermediate. The calculated free energies of activation are in close agreem...
Studies of proliferative capabilities in isolated epidermal basal and differentiated cells.

In order to initiate studies to determine whether the restriction of mitosis to the basal layer in normal mammalian epidermis is a function of intrinsic changes in the cell or of environmental factors, a procedure which facilitates the isolation and separation of epidermal cells into suspensions of predominantly basal cells and of spinous and granular cells, respectively, was established. The comparatively high viability and good morphological preservation of the cells obtained by this method allowed us (1) to observe and describe morphological characteristics of keratinocytes in various stages of differentiation using phase contrast microscopy and (2) to study their respective proliferative capabilities in vitro using cell culture and metabolic tracer techniques. Over 200 successful primary cultures of basal cells have been performed to date but 56 attempts with suspensions composed of spinous and granular cells were unsuccessful. The incorporation of thymidine- 3 H, a specific precursor of DNA, into acid precipitable form after 8 hours incubation was nearly 100 fold greater in basal cell suspensions than in suspension of more differentiated cells. These observations suggest that the factors responsible for the absence of mitosis in cells from the upper epidermal layers are related to irreversible changes in the cell itself rather than to in situ environmental influence. Other evidence to support this tentative view is discussed.
Single Qdot-labeled glycosylase molecules use a wedge amino acid to probe for lesions while scanning along DNA

Within the base excision repair (BER) pathway, the DNA N-glycosylases are responsible for locating and removing the majority of oxidative base damages. Endonuclease III (Nth), formamidopyrimidine DNA glycosylase (Fpg) and endonuclease VIII (Nei) are members of two glycosylase families: the helix-hairpin-helix (HhH) superfamily and the Fpg/Nei family. The search mechanisms employed by these two families of glycosylases were examined using a single molecule assay to image quantum dot (Qdot)-labeled glycosylases interacting with YOYO-1 stained λ-DNA molecules suspended between 5 µm silica beads. The HhH and Fpg/Nei families were found to have a similar diffusive search mechanism described as a continuum of motion, in keeping with rotational diffusion along the DNA molecule ranging from slow, sub-diffusive to faster, unrestricted diffusion. The search mechanism for an Fpg variant, F111A, lacking a phenylalanine wedge residue no longer displayed slow, sub-diffusive motion compared to wild type, suggesting that Fpg base interrogation may be accomplished by Phe(111) insertion.
BOLD response to working memory not related to cortical thickness during early adolescence.

Background Significant cortical thinning and neural resource allocation changes emerge during adolescence; however, little is known of how morphometric changes influence neural response to cognitive demands. This study used a novel multimodal imaging registration technique to examine the relationship between brain structure and function during adolescence.
Gender, status and family fortunes in the white-fronted bee-eater

Models of how people make decisions are central to economic theory. But when cast in a darwinian framework, such models provide insights into animal social behaviour. This is especially true of family-based societies in which the profitability of pursuing different behaviours is strongly influenced by gender, kinship and social position within the group. The potential of this approach is shown by modelling the reproductive decisions facing individuals in a complex bird society, that of the white-fronted bee-eater.
Health Care Utilization and Hypertension Management in Community-Based Elderly Korean Immigrants

Despite the nation-wide efforts to improve the health status of minority immigrants, studies documenting the outcomes of these efforts are lacking. The purpose of this study is to examine health care utilization and hypertension management in community-based elderly Korean immigrants to the US In this descriptive study, 70 elderly Korean immigrants were recruited from a Korean senior center and church. Health care utilization was assessed with a self-report questionnaire and hypertension management was ascertained through the objective measurement of blood pressure and a self-report questionnaire. Result indicated that 87 % of elderly Korean immigrants received regular health check-ups. Although their hypertension was not managed effectively, all participants with a diagnosis of hypertension were aware of it and were taking blood pressure medications. This study provides an overview of health care utilization and hypertension management in elderly Korean immigrants as well as ideas on ways to reach out to minority older adults for further health promoting interventions.
Married Women's Resource Position and Household Food Expenditures in Cebu, Philippines.

This study analyzes how married women use their access to and control over economic resources to increase household spending on food. Using data from Cebu, Philippines, where child malnutrition is high, this study finds that the more income women earn and control, the more households spend on food. Women's control over their income is particularly important for increasing food expenditures in the poorest households. In richer households, women who earn little of their own income also use spouse income transfers to increase food expenditures. The findings from this study suggest that in a developing country setting, improving women's economic status so that they earn and control more household resources can increase household spending on goods that benefit children.
Preparation, characterization and in vitro analysis of novel structured nanofibrous scaffolds for bone tissue engineering.

Abstract In a previous study, a three-dimensional nanofibrous spiral scaffold for bone tissue engineering was developed, which showed enhanced human osteoblast cell attachment, proliferation and differentiation compared with traditional cylinder scaffolds, owing to the incorporation of spiral structures and nanofiber. However, the application of these scaffolds to bone tissue engineering was limited by their weak mechanical strength. This limitation triggered the design for novel structured scaffolds with reinforced physical characteristics. In this study, spiral polycaprolactone (PCL) nanofibrous scaffolds were inserted into poly(lactide-co-glycolide) (PLGA) microsphere sintered tubular scaffolds to form integrated scaffolds to provide mechanical properties and bioactivity appropriate for bone tissue engineering. Four experiment groups were designed: PLGA cylinder scaffold; PLGA tubular scaffold; PLGA tubular scaffold with PCL spiral structured inner core; PLGA tubular scaffold with PCL nanofiber containing spiral structured inner core. The morphology, porosity and mechanical properties of the scaffolds were characterized. Furthermore, human osteoblastic cells were seeded on these scaffolds, and the cell attachment, proliferation, differentiation and mineralized matrix deposition on the scaffolds were evaluated. The integrated scaffolds had Young’s modulus 250–300 MPa, and compressive strength 8–11 MPa under uniaxial compression. With the addition of an inner highly porous insert to the tubular shell, human osteoblast cells seeded on the integrated scaffolds showed slightly higher cell proliferation, 20–25% more alkaline phosphatase expression and twofold higher calcium deposition than those on the cylinder and tubular scaffolds. Furthermore, compared with sintered PLGA cylinder scaffolds, the integrated scaffolds allowed better cellular infiltration Therefore, this design demonstrates great potential for integrated scaffolds in bone tissue engineering applications.
GcvA interacts with both the α and σ subunits of RNA polymerase to activate the Escherichia coli gcvB gene and the gcvTHP operon

The glycine cleavage enzyme system in Escherichia coli provides one-carbon units for cellular methylation reactions. The gcvB gene encodes two small RNAs that in turn regulate other genes. The GcvA protein is required for expression of both the gcvTHP (PgcvT) and gcvB (PgcvB) promoters. However, the architectures of the two promoters are different, with the PgcvT promoter representing a class III activator-dependent promoter and the PgcvB promoter representing a class II activator-dependent promoter. The RNA polymerase holoenzyme was examined for its role in transcription activation of the gcvTHP operon and the gcvB gene by the GcvA protein. The results suggest that GcvA interacts with the RNA polymerase α subunit for activation of the gcvTHP operon and interacts with the RNA polymerase σ subunit for activation of the gcvB gene.
The assessment of human performance for the analysis of space missions.

The authors consider the problem of developing a computer program to assist the aerospace psychologist in the task of assessing human performance reliability. The procedures which were developed permit an analysis of physiological and psychological variables relevant to human performance in space, the stressors that cause degradation in performance because they impair physiological and psychological functions, and the tasks that humans must perform. The degrading effect of each stressor is specified for each physiological and psychological variable, and the combined effect of all stressors on each variable is calculated. The status of all physiological and psychological variables relevant to the performance of a given task is assessed and a resultant reliability for each task is calculated. The minimum reliability within a given time period is used to produce a reliability profile. The system was used to obtain reliability ratings based on estimates of conditions for a hypothetical lunar mission.
Toward critical spatial thinking in the social sciences and humanities

The integration of geographically referenced information into the conceptual frameworks and applied uses of the social sciences and humanities has been an ongoing process over the past few centuries. It has gained momentum in recent decades with advances in technologies for computation and visualization and with the arrival of new data sources. This article begins with an overview of this transition, and argues that the spatial integration of information resources and the cross-disciplinary sharing of analysis and representation methodologies are important forces for the integration of scientific and artistic expression, and that they draw on core concepts in spatial (and spatio-temporal) thinking. We do not suggest that this is akin to prior concepts of unified knowledge systems, but we do maintain that the boundaries to knowledge transfer are disintegrating and that our abilities in problem solving for purposes of artistic expression and scientific development are enhanced through spatial perspectives. Moreover, approaches to education at all levels must recognize the need to impart proficiency in the critical and efficient application of these fundamental spatial concepts, if students and researchers are to make use of expanding access to a broadening range of spatialized information and data processing technologies.
Improving supply chain information sharing using Design for Six Sigma

Accurate and reliable information is needed to support decision-making processes. Due to the large number of participants typically involved in supply chain operations, organizations often find that it is difficult to effectively share information within a supply chain; hence, this research examined ways to improve information sharing within supply chain operations for one marine transportation services organization. An action research, case study approach used the Design for Six Sigma (DFSS) methodology to design an information technology solution that effectively communicates information between the layers within the supply chain regarding the movement of materials via inland tank barges. The comparative analysis of verification and baseline measurements conducted suggests this project was successful because the new process fulfilled the needs of the work environment for which it was designed. For the organization that participated in this research, the successful adoption of the new approach for information sharing improved communication and decision making within their supply chain.
Optimum experimental designs for comparative bioavailability studies

Abstract The purpose of a pharmacokinetic drug-drug interaction study is to investigate whether coadministration of two or several drugs will alter the absorption/distribution/metabolism/elimination profile of each drug. To design the study and analyze the data in a way which can provide answers to our questions, we introduce a model for m-component drug-drug interaction bioavailability studies, and under that model we identify optimal design for the criterion of strongly universal optimality. Using some concepts and results in the areas of resistant block designs and finite geometries, several families of strongly universally optimal designs for comparative bioavailability studies are constructed.
The influence of organic matter and atmospheric deposition on the particulate trace metal concentration of northwest Atlantic surface seawater

Abstract Particulate trace metals (PTM), organic carbon (POC), and organic nitrogen (PON) were measured in a series of surface bucket samples collected between the New England coast of the United States and Bermuda. PTM concentrations were lower or equivalent to the lowest PTM concentrations reported in the literature. Examination of the relative variations in PTM with respect to particulate aluminum and carbon led to the conclusion that organic matter was the probable regulator of PTM abundance in open-ocean surface waters and was important in this respect for continental shelf and slope waters as well. Enrichment factors of trace metals relative to their crustal abundances were found to be similar in the atmosphere sampled in Bermuda and in Sargasso Sea surface water particulate matter. A simplistic vertical flux model was constructed which showed atmospheric input of trace metals to the Sargasso Sea to be of the same approximate magnitude as the rate of removal of PTM from the mixed layer by sinking in association with POC. Essentially all of the particulate Al, Fe, and Mn in the Sargasso Sea mixed layer was attributed to aeolian sources. The fate of other atmospherically derived trace metals in the Sargasso Sea mixed layer was suggested to be a function of their solubility in seawater.
Two daily melatonin injections differentially induce nonshivering thermogenesis and gonadal regression in the mouse (Peromyscus leucopus).

Abstract Female white-footed mice ( Peromyscus leucopus ) were injected twice daily with 5, 10, 50, 100 μg melatonin (MEL) or saline. Injections were given for 7 weeks at 2 and 12 hours after lights-on under a long day (LD 16:8) photoperiod. Afternoon administration of MEL induced gonadal regression, although a dose of 50 μg or more was necessary to obtain a maximal response. A 5 μm MEL injection in the afternoon resulted in intermediate reproductive tract weights. In white-footed mice a morning MEL injection did not abolish the reproductive regression induced by an afternoon injection. Mice receiving 10, 50 or 100 μg MEL daily exhibited increased nonshivering thermogenesis (NST), irrespective of the timing of the injection. Daily injections of 5 μg MEL had little effect on NST. These observations suggest that “up and down regulation” of MEL receptors may not be important in P. leucopus . Further, the mechanism by which MEL controls reproduction is different from that for NST.
Lattice spacing of hypothetical AgCl and AgBr with "switched-off" van der Waals interactions.

Model calculations show that reduction of van der Waals interactions in AgCl and AgBr to the strength of those in comparable alkali halides leads to hypothetical silver halide crystals with properties similar to those of alkali halides. In particular, the nearest-neighbor distances agree with the sum of Pauling ionic radii. The findings support previous indications that the peculiar cohesive properties of silver halides originate from very strong van der Waals forces rather than from partial covalency.
Sources of local variation in polynuclear aromatic hydrocarbon and pesticide body burden in oysters (Crassostrea virginica) from Galveston Bay, Texas

Abstract 1. Eggs and sperm contain significantly more PAH (polynuclear aromatic hydrocarbon) than somatic tissues in oysters ( Crassostrea virginica ) taken from Galveston Bay. 2. The quantity of gonadal material was the most important correlate of PAH body burden. 3. Eggs, but not sperm, were enriched in chlorinated compounds (e.g. DDD, chlordane), while both eggs and sperm were enriched in total PCBs relative to somatic tissue. 4. Oysters may lose up to 50% of their total body burden of certain PAHs and pesticides in a single spawn.
Whitman in The Southern Literary Messenger

Discusses Southern Literary Messenger editor George W. Bagby's dislike of Whitman and quotes from his published comments about the poet, including his 1862 preface to a parody of Whitman's poetry entitled "The War."
Commentary on: Race as a variable in cross-cultural research.

Abstract Original abstract Documentation of health disparities in the United States has spurred increased interest in cross-cultural research and comparison of outcomes between minority and majority groups. The variables of race and ethnicity are used to distinguish among groups of interest in these studies. The purpose of this article is to review the meanings of race and ethnicity as these terms are used in nursing and other health-related research, and to highlight some advantages and disadvantages with their use in the literature. An illustration is provided using findings from a recent study exploring determinants of health for Hispanic farm workers. Race as a variable was included in this study to examine the possibility of discrimination as a health determinant. Racial categories were not meaningful to many respondents in this sample, however, and racerelated data were not reliable. Sugestions are made for improving the quality of data related to race and ethnicity variables as they are associated with health outcomes. (Ward L. Race as a variable in cross-cultural research. Nurs Outlook 2003;51:120-5.)
ESDP and NATO: Assuring complementarity

(2004). ESDP and NATO: Assuring complementarity. The International Spectator: Vol. 39, No. 1, pp. 51-70.
Swahili History and Society to 1900: A Classified Bibliography

Several years ago, Derek Nurse and I began to consider the increasing need to make revisions to our book, The Swahili: Reconstructing the History and Language of an African Society, 800-1500. We knew there had been significant archeological finds subsequent to its publication in 1985, but we were surprised to discover that hundreds of new books and articles had appeared. It therefore seemed expedient, not simply to revise the earlier work, but to compile a comprehensive new bibliography on early Swahili history and society that would facilitate thorough reconsideration of the issues in the future. This now includes 700 items, 428 published before 1985 and 272 published after. This is a massive literature, and it will make extensive demands on those working in the field (Spear 1999).The focus here is on the history and development of coastal societies over the past two millennia, but I have included recent ethnography, linguistics, and history for comparative purposes. What is missing, however, are sources covering literature and the arts, for which one may consult Kelly Askew's excellent online bibliography (Askew 1999). I have included mainly published work, but unpublished theses and papers are also included where available. I have not, however, included archival materials in government (e.g., Tanzanian, Zanzibari, British, German, Indian, French, U.S.), mission (CMS, UMCA, LMS), or local (Salem, Hamburg, Rhodes House) collections, nor have I included material in mission publications.The bibliography is subdivided by discipline—archaeology, linguistics and language, ethnography, and history. Most items have been confirmed in OCLC WorldCat or other authoritative sources, correcting numerous errors in previous citations. Arabic names are alphabetized as they appear, inconsistently, in databases for ease of finding.
Financial Reporting, Democracy and Environmentalism: A Critique of the Commodification of Information

Abstract So-called modern financial reporting theory (MFRT) is presented as a product of economic imperialism, and critically reviewed as a totalizing theory that attempts to silence "other voices". Laclau and Mouffe's discourse theory of politics is employed to expose the weaknesses of MFRT's claims to methodological superiority, and to contest the claim that financial information should be viewed as a commodity. The contingency and contestability of any articulated position regarding physical, social, political or personal reality is emphasized in contradiction to the methodological individualism and naive realism of MFRT. The importance of discourse in articulating social identity and creating political alliances is illustrated with respect to environmentalism. The "green investment" movement and environmental politics are also used to demonstrate that, contrary to the claims of MFRT, accounting information is fundamentally intertwined with ethical, social and political decision-making and policy evaluation. On this basis, the commodification is criticized as a threat to the healthy functioning of a pluralistic democracy on the grounds that it restricts access to information that is crucial to marginal political movements.
Long-term base current instability in AlGaAs/GaAs HBTs: physical mechanisms, modeling, and SPICE simulation

Abstract This paper provides an overview of the long-term base current instability in the AlGaAs/GaAs heterojunction bipolar transistor (HBT), which is a main mechanism governing the HBT long-term current gain drift and thus a major concern for the HBT reliability. Topics covered include: (1) types of base current instability and their underlying physical mechanisms; (2) leakage currents in the HBT and their relevance to the reliability; (3) electro-thermal interaction and their impact on the HBT reliability; (4) analytic model for predicting the HBTs mean time to failure (MTTF); and (5) SPICE implementation and simulation of HBT circuit reliability. Measurements and device simulation results are also included in support of the modeling and analysis.
A Glimpse at Loop 1 Movement in Smooth Muscle Using Intrinsic Tryptophan Fluorescence

Smooth muscle myosin has two N-terminal isoforms that result from alternative splicing of loop 1. Loop 1 contains a seven amino acid insert (QGPSFSY) in one isoform (SM-B) that is absent in the other (SM-A). It has been shown that the presence of the insert causes a two-fold increase in the rate of in-vitro actin sliding velocity and actin-activated ATPase (Rovner et al., J. Muscle Res. Cell Motil. 18:103, 1998). Based on these results and its proximity to the active site it was hypothesized that loop 1 plays a role in modulating the release of ADP (Spudich, Science 372:515, 1994). However, little is known about the conformation of loop 1 in different nucleotide states, as it is absent in crystal structures. To examine the position of loop 1 and its potential role in ADP release we have engineered a single tryptophan residue into loop 1 at position 215. Using the intrinsic tryptophan fluorescence from W215 and fluorescent analogs of ADP and ATP we have looked at the position of loop 1 as a function of temperature. The results suggest two conformations of loop 1 in the ADP state, both an open and closed form. The distance between loop 1 and the active site decreases for both nucleotides from 25-15°C. At 10 °C loop 1 moves away from the active site in the ADP state, while there is no additional movement in the presence of ATP. This is the first data to demonstrate movements of loop 1 associated with different nucleotide states of the myosin active site, giving insight into how it may contribute to nucleotide release.
Carbon and oxygen atom mobility during activation of Mo2C catalysts

Abstract Temperature-programmed desorption (TPD) and reduction (TPR) were used to study the activation of Mo 2 C for ethylene hydrogenation at 298 K. Mo 2 C can incorporate large amounts of oxygen, and since oxygen is a poison for the reaction, it must be removed from the surface to activate the catalyst. As oxygen is removed from the surface by evacuation or reduction, it is replenished by diffusion of oxygen from the bulk. Therefore, the equivalent of several monolayers must be removed to obtain an oxygen-free surface, although it is not necessary to remove all the bulk oxygen. Furthermore, the oxygen cannot be removed by evacuation or reduction without also removing a significant amount of bulk carbon. Although the initial activity of the catalyst for ethylene hydrogenation is independent of the amount of carbon removed, the rate of deactivation of the Mo 2 C strongly depends on the extent of carbon removal. As more carbon is removed, the rate of deactivation increases and the shape of the activity-time curve (deactivation curve) changes from an exponential decay to a sigmoidal shape. TPR spectra of oxygen chemisorbed on the surface after two different activation procedures showed that the surface of the catalyst depends on the extent of carbon removal. As more carbon is removed from the Mo 2 C, the oxygen is bound more tightly to the surface. This suggests that ethylene also might be bound more tightly on the carbon-deficient catalyst, which is consistent with the higher rate of deactivation.
A Clovis well at the type site 11,500 B.C.: The oldest prehistoric well in America

An enigmatic circular pit uncovered during archaeological excavations at the Clovis type site, Blackwater Draw, New Mexico, in 1964 has been reexposed and posited as a water well excavated by Clovis people around 11,500 B.C. The prehistoric well, the oldest in the New World, was probably a dry hole. Other Clovis wells may exist in the area. The excavation of wells near where there had been surface water shortly before adds to the evidence for drought during the Pleistocene-Holocene transition. © 1999 John Wiley & Sons, Inc.
Effects of long-term corn consumption on brain serotonin and the response to electric shock

Rats fed tryptophan-poor corn diets have reduced levels of brain serotonin and show increased responsiveness to electric shock. This diet-induced hyperalgesia can be reversed by feeding the animals diets with adequate amounts of tryptophan, or by systemic injections of the amino acid.
Case 4--2005. Utility of transesophageal echocardiography in the diagnosis of a previously undetected atrial septal aneurysm with shunt.

EFECTS OF THE interatrial septum are among the most common congenital cardiac lesions found in adults. The foramen ovale, a fetal remnant, remains probe patent in more than one third of the general population, making it the most common congenital cardiac abnormality. Functional closure of the foramen ovale usually occurs soon after birth when the left atrial pressure rises and presses the valve of the fossa ovalis against the septum secundum. A patent foramen ovale (PFO) occurs when the foramen ovale does not anatomically seal. This relatively common entity is detectable in up to 34% of the population at postmortem examination. 1,2 The incidence has been shown to be even higher in patients with stroke. 3 Complications associated with a PFO include right-to-left shunting with refractory hypoxemia, paradoxic embolism, migraine headache, 4 transient global amnesia, 5 decompression illness with paradoxic gas embolism in divers and astronauts, 6 and orthostatic desaturation with platypnea-orthodeoxia syndrome.7 Atrial septal aneurysm (ASA) is frequently seen in association with a PFO,8 and its presence has been related to focal cerebral events including stroke and transient ischemic attacks. Because of this association, paradoxic embolism is believed to be a likely mechanism of embolism in many patients with ASA. Transesophageal echocardiography (TEE) is the modality of choice for the detection of PFO and ASA. Because of the increasingly routine use of TEE in the operating room during cardiac surgery, it can be expected that more cases of previously undiagnosed PFO and ASA will be detected. The question then becomes whether these findings should prompt further surgical intervention, particularly if the patient is asymptomatic. Unfortunately, at this time, there are no data to support the optimal approach to this clinical dilemma. The authors present a patient with a history of transient ischemic attacks (TIA) of unknown origin who was scheduled for elective off-pump coronary artery bypass (OPCAB) surgery. Preoperative diagnostic tests did not disclose the source of TIAs; however, intraoperative TEE revealed an ASA with PFO leading to alteration of the planned surgical procedure.
Developmental Alterations in 5-Hydroxytryptamine Concentration and Turnover after Treatment of Neonatal Rats with 5,7-Dihydroxytryptamine

Abstract Early disruption of the serotonin neurotransmitter system may have important consequences for normal neurophysiological development. In order to further understand the neurochemical changes which occur after early insults to this system, intracerebroventricular injections of the serotonin-selective toxin, 5,7-dihydroxytryptamine were given to Sprague–Dawley rat pups on Day 3 of life. Serotonin and 5-hydroxyindoleacetic acid concentration in cortex, striatum, hippocampus, and brainstem were measured after 4, 8, and 12 weeks. In controls, serotonin concentration in the striatum and cortex increased from 4 to 12 weeks, while it reached adult levels by 4 weeks in the hippocampus. 5-Hydroxyindoleacetic acid increased in cortex and hippocampus and was unchanged after 4 weeks in the striatum. An index of serotonin turnover (5-hydroxyindoleacetic acid/serotonin) decreased in striatum and cortex, but increased in the hippocampus over time. 5,7-Dihydroxytryptamine treatment induced permanent decreases in serotonin and 5-hydroxyindoleacetic acid concentration in all three forebrain regions, but had region- and time-specific effects on serotonin turnover. In the brainstem of controls, serotonin concentration increased from 4 to 12 weeks, while 5-hydroxyindoleacetic acid concentration was unchanged, resulting in decreasing turnover. After 5,7-dihydroxytryptamine treatment, the brainstem did not show depletions of serotonin concentration in spite of significant serotonin neuronal loss, suggesting that compensatory mechanisms in remaining neurons may permit increased serotonin production. Regional and time-dependent responses to serotonin depletion may have functional implications for the developmental regulation of serotonin transmission after early insults to this neurotransmitter system.
Effects of cardiac glycosides on the abnormal pulmonary circulation of the dog

Abstract Hemodynamic effects of acetyl strophanthidin were studied in fully recovered, awake, unsedated, instrumented dogs with a ligated left pulmonary artery. Increased myocardial contractility, a negative chronotropic effect, and systemic vasoconstriction were indicated by increased cardiac output, slower heart rate, increased peak stroke velocity, and increased systemic arterial pressure and systemic vascular resistance. In addition, active pulmonary vasoconstriction was shown by increased pulmonary arterial pressure and pulmonary vascular resistance. Comparison of these with our early results in intact dogs with bipulmonary circulation revealed that acetyl strophanthidin produced a greater rise in pulmonary vascular resistance in dogs which have an increased ratio of blood flow to available pulmonary vascular bed. Hemodynamic effects of acetyl strophanthidin were also studied in a fully awake dog with an aortopulmonary shunt. An increased magnitude of pulmonary vasoconstriction produced by acetyl strophanthidin in dogs with relatively and absolutely increased pulmonary blood flow was apparent after correction for passive effects of increased pulmonary blood flow and increased left atrial pressure. These findings may have implications regarding one determinant of pulmonary vasoreactivity.
A spectral gap for transer operators of piecewise expanding maps

We provide a simplified proof of the existence, under some assumptions, of a spectral gap for the Perron-Frobenius operator of piecewise uniformly expanding maps on Riemannian manifolds when acting on some Sobolev spaces. Its consequences include, among others, the existence of invariant physical measures, and an exponential decay of correlations for suitable observables. These features are then adapted to different function spaces (functions with bounded variation or bounded oscillation), so as to give a new insight of - and generalize - earlier results.
Analog specific aberrancies in antifolate inhibition of L1210 cell dihydrofolate reductase

Abstract During studies with L1210 cells and a variety of folate analogs, large discrepancies were revealed between data on membrane transport, on inhibition of dihydrofolate reductase in cell-free extracts, and on inhibition of growth in culture for 10-oxa-, 10-benzyl- and 10-phenethyl-aminopterin, and for 3-deaza, 10-methyl-aminopterin. While aminopterin, 10-methyl (methotrexate)-, 10-ethyl- and 10-propyl-aminopterin were tight binding inhibitors ( K i : 2–3 × 10 −12 M) of dihydrofolate reductase in cell-free extracts from L1210 cells, the other four analogs were only weak competitive inhibitors ( K i = 3–300 × 10 −8 M). Similar differences among analogs were observed for inhibition of dihydrofolate reductase in cell-free extracts from Sarcoma 180 and Ehrlich cells, but not for this enzyme in microbial cell-free extracts. There were only small differences in the transport of all of the analogs by L1210 cells. Inhibition of L1210 cell growth in culture by 10-oxa-, 10-benzyl- and 10-phenethyl-aminopterin and by 3-deaza, 10-methyl-aminopterin, in contrast to the other analogs, was several orders of magnitude greater than that predicted from the data on dihydrofolate reductase inhibition. The extent of binding of 10-oxa-, 10-benzyl- and 10-phenethyl-aminopterin, and of 3-deaza and 10-methyl-aminopterin to dihydrofolate reductase in intact L1210 cells, in contradistinction to that seen for the cell-free enzyme preparations, approached that observed for methotrexate; these estimates of drug-enzyme interaction in situ were more predictive of the extent of inhibition by these analogs of L1210 cell growth in culture.
Systems work at Microsoft Research

Operating Systems Review presents a special issue on systems work at Microsoft Research. This introduction sets the context for the papers.
Wieferich Primes and Period Lengths for the Expansions of Fractions

It is well known that some decimal expansions terminate, while others repeat, at least eventually, in patterns, which may be short or lengthy (we shall call this repeating pattern the period of the expansion). Here we will extend some known results while exploring expansions of fractions in any base. Our goal will be to find a formula for the length of the period of such expansions. The interested reader is referred to the recent award-winning article by Jones and Pearce, who show how to display such decimal expansions graphically [3]. We will consider both the expansions of (the reciprocals of) primes and of composites. It would seem that the easier part of this problem would be that of primes. However, there are difficulties/anomalies among primes that make it hard to find a formula that works in all cases. The most interesting such case is that of Wieferich primes, whose reciprocals are characterized by expansions whose periods are the same length as the periods of their squares. For example, the length of the period of 1/1093 is 1092 which is the same as that of 1/10932. This, as we shall see, is not normally the case. For someone seeking a simple formula, this is bad news. However, as our table at the end shows, Wieferich primes are quite rare.
Dynamic spherical volumetric simplex splins with application in biomedical simulation

This paper presents a novel computational framework based on dynamic spherical volumetric simplex splines for simulation of genuszero real-world objects. In this framework, we first develop an accurate and efficient algorithm to reconstruct the high-fidelity digital model of a real-world object with spherical volumetric simplex splines which can represent with accuracy geometric, material, and other properties of the object simultaneously. With the tight coupling of Lagrangian mechanics, the dynamic volumetric simplex splines representing the object can accurately simulate its physical behavior because it can unify the geometric and material properties in the simulation. The visualization can be directly computed from the object's geometric or physical representation based on the dynamic spherical volumetric simplex splines during simulation without interpolation or resampling. We have applied the framework for biomechanic simulation of brain deformations, such as brain shifting during the surgery and brain injury under blunt impact. We have compared our simulation results with the ground truth obtained through intra-operative magnetic resonance imaging and the real biomechanic experiments. The evaluations demonstrate the excellent performance of our new technique presented in this paper.
The Politics of Women’s Rights in Iran

Before turning to an academic career in Anthropology, Arzoo Osanloo worked in the United States as a practicing attorney and human rights advocate, specializing in asylum and immigration law. Her b...
Control of Chloroplast RNA Synthesis in Chlamydomonas reinhardi

WHEN certain strains of Escherichia coli are deprived of a required amino-acid their production of ribosomal ribo-nucleic acid (rRNA) and soluble RNA is reduced. The removal of any amino-acid has this effect. Such strains are said to be stringent. Strains mutant at the RC locus do not respond in this way to the removal of a required amino-acid and are said to be relaxed1,2.
Single-particle statistics derived from light-blockage instruments

Abstract This study examines the distribution of measured diameters of single particles. Diameter distributions of six particles were compared with the theoretical gamma, chisquared, and Student's t distributions. Five aluminum oxide particles of varying shape, and a nitrocellulose spheroid were each repeatedly sized thirty-two times using a light-blockage particle counter. For each observation, an equivalent diameter was calculated from the projected cross-sectional area of the particle. Mean diameters and standard deviations were then calculated from these values. A qualitative description of each particle's shape was determined using a scanning electron microscope. The shapes ranged from spheroidal to flake-like. Using the Student t distribution and specified confidence levels, an estimate was also made of the minimum number of trials necessary to reproduce the experimental results.
The amazing predictive power of folk psychology

(1992). The amazing predictive power of folk psychology. Australasian Journal of Philosophy: Vol. 70, No. 1, pp. 99-105.
The Human Polyomavirus, Jcv, Does Not Share Receptor Specificity with SV40 on Human Glial Cells

The initial event in the life cycle of a virus is its interaction with specific receptors present on the surface of a cell. Understanding these interactions is important to our understanding of vir...
Amines as extracting agents for the quantitative determinations of actinides in biological samples

The present manuscript reviews the use of amines (primary, secondary and tertiary chains and quaternary ammonium salts) as extracting agents for the quantitative determination of actinides in biological samples. Among the primary amines, only Primene, JM-T is used to determine Pu in urine and bone. No one has investigated the possibility of using secondary amines to quantitatively extract actinides from biological samples. Among the tertiary amines, tri-n-octylamine, tri-iso-octylamine, tricaprylamine (Alamine) and trilaurylamine (tridodecylamine) are used extensively to extract and separate the actinides from biological samples. Only one quanternary ammonium salt, methyltricapryl ammonium chloride (Aliquat-336), is used to extract Pu from biological samples.
LABELING OF ABUSE EXPERIENCES AND RATES OF VICTIMIZATION

Research has consistently found that a history of previous sexual victimization increases risk for future sexual assault, which might be due to women with a history of sexual victimization having difficulty identifying risky cues and not perceiving their own vulnerability for future assaults. This study investigated how acknowledgment of previous experiences with interpersonal violence is related to risk perception and rates of victimization. Participants were 198 college women who completed assessments of victimization, personal risk appraisal, and acknowledgment. Analyses indicated differences in rates of victimization based on labeling of experiences and differences in efforts to change behaviors to reduce risk for future assaults based on level of acknowledgment. Also, there were a number of situational factors significantly related to likelihood of acknowledgment. The findings differed for physical and sexual violence. This study suggests that acknowledgment is an important factor to consider in studies of sexual and physical revictimization.
Selecting relevant nodes and structures in biological networks. BiNAT: a new plugin for Cytoscape

Summary: In order to understand a network function, it’s necessary the understanding of its topology, since the topology is designed to better undertake the function, and the efficiency of network function is influenced by its topology. For this reason, topological analysis of complex networks has been an intensely researched area in the last decade. Results: Here we propose BiNAT, a Cytoscape [1] plugin able to perform network analysis, providing a full set of useful tools to discover the most significant nodes and structures in a network. Conclusions: The plugin has been approved on the official Cytoscape plugins repository and it is downloadable directly from this site: http://dmb.iasi.cnr.it/binat.php where a full guide is also available.