cssi/SciSciGPT-SciSciNet huggingface dataset:
B-cell development in the amphibian Xenopus.

Summary: The amphibian Xenopus and mammals have similar organization and usage of their immunoglobulin gene loci with combinatorial joining of V, D and J elements. The differences in B-cell development between mammals and this amphibian are due to major differences in developmental kinetics, cell number and lymphoid organ architecture. Unlike mammals, the immune system of Xenopus develops early under pressure to develop quickly and to produce a heterogeneous repertoire before lymphocyte numbers reach 5,000, thereby imposing a limitation on clonal amplification. In addition, it is submitted to metamorphosis. Thus, during the early antigen-independent period, several features of B-cell development related to immune diversification are under strict genetically preprogramed control: 1) D reading frames contribute complementary determining region 3 with features that occur in mammals by somatic selection, 2) the temporal stepwise utilization of VH genes in Xenopus occur in families probably because of structural DNA features rather than their position in the locus. Larval and adult immune responses differ in heterogeneity. Larval rearrangements lack N diversity. During the course of immune responses, somatic mutants are generated at the same rate as in other vertebrates but are not optimally selected, probably due to the simpler organization of the lymphoid organs, with neither lymph nodes nor germinal centers resulting in poor affinity maturation. Switch from IgM to other isotypes is mediated by loop-excision deletion of the IgM constant region gene via switch regions which, unlike their mammalian counterpart, are A-T rich and reveal conserved microsites for the breakpoints.
Insulin-like growth factor-I provokes functional antagonism and internalization of β1-Adrenergic receptors

Hormones that activate receptor tyrosine kinases have been shown to regulate G protein-coupled receptors, and herein we investigate the ability of IGF-I to regulate the β1-adrenergic receptor. Treating Chinese hamster ovary cells in culture with IGF-I is shown to functionally antagonize the ability of expressed β1-adrenergic receptors to accumulate intracellular cAMP in response to stimulation by the β-adrenergic agonist Iso. The attenuation of β1-adrenergic action was accompanied by internalization of β1-adrenergic receptors in response to IGF-I. Inhibiting either phosphatidylinositol 3-kinase or the serine/threonine protein kinase Akt blocks the ability of IGF-I to antagonize and to internalize β1-adrenergic receptors. Mutation of one potential Akt substrate site Ser412Ala, but not another Ser312Ala, of the β1-adrenergic receptor abolishes the ability of IGF-I to functionally antagonize and to sequester the β1-adrenergic receptor. We also tested the ability of IGF-I to regulate β1-adrenergic receptors a...
Streetscore -- Predicting the Perceived Safety of One Million Streetscapes

Social science literature has shown a strong connection between the visual appearance of a city's neighborhoods and the behavior and health of its citizens. Yet, this research is limited by the lack of methods that can be used to quantify the appearance of streetscapes across cities or at high enough spatial resolutions. In this paper, we describe 'Streetscore', a scene understanding algorithm that predicts the perceived safety of a streetscape, using training data from an online survey with contributions from more than 7000 participants. We first study the predictive power of commonly used image features using support vector regression, finding that Geometric Texton and Color Histograms along with GIST are the best performers when it comes to predict the perceived safety of a streetscape. Using Streetscore, we create high resolution maps of perceived safety for 21 cities in the Northeast and Midwest of the United States at a resolution of 200 images/square mile, scoring ~1 million images from Google Streetview. These datasets should be useful for urban planners, economists and social scientists looking to explain the social and economic consequences of urban perception.
Teaching Children with Autism in Small Groups with Students Who are At-Risk for Academic Problems: Effects on Academic and Social Behaviors

Students with ASD are often taught in individual instructional arrangements, even when they receive educational services in inclusive settings. Providing intervention in small group arrangements may increase opportunities for social interactions, particularly when these opportunities are systematically planned. In this study, academic instruction was conducted in small groups consisting of one student with ASD and peers who were socially competent but at risk for academic failure. All students learned targeted academic behaviors and increased their use of targeted social behaviors during instructional sessions. Generalization of social behaviors to a less-structured context was variable. Results suggest that small group instruction may be a feasible and preferred alternative to individual instruction for students with ASD.
Light emission from semiconducting polymers: Light-emitting diodes, light-emitting electrochemical cells, lasers and white light for the future

High performance photonic devices fabricated from conjugated polymers have been demonstrated, including diodes, light emitting diodes, photodiodes, field-effect transistors, polymer grid triodes, light emitting electrochemical cells, optocouplers and lasers, i.e. essentially all the categories which characterize the field of photonic devices. In many cases, semiconducting polymer-based devices have reached performance levels comparable to their inorganic counterparts. This short review focuses on recent progress in the area of light emission from semiconducting polymers.
55Mn ENDOR of the S2-State Multiline EPR Signal of Photosystem II: Implications on the Structure of the Tetranuclear Mn Cluster

We have performed continuous-wave electron paramagnetic resonance (CW-EPR) and electron spin echo electron nuclear double resonance (ESE-ENDOR) experiments on the multiline form of the S2-state of untreated, MeOH-treated, and ammonia-treated spinach photosystem II (PS II) centers. Through simultaneously constrained simulations of the CW-EPR and ESE-ENDOR data, we conclude that four effective 55Mn hyperfine tensors (AX, AY, AZ) are required to properly simulate the experimental data [untreated and MeOH-treated PS II centers (MHz): −232, −232, −270; 200, 200, 250; −311, −311, −270; 180, 180, 240; ammonia-treated PS II centers (MHz): 208, 208, 158; −150, −150, −112; 222, 222, 172; −295, −315, −390]. We further show that these effective hyperfine tensors are best supported by a trimer/monomer arrangement of three Mn(IV) ions and one Mn(III) ion. In this topology, MnA, MnB, and MnC form a strongly exchange coupled core (JAB and JBC < −100 cm-1) while MnD is weakly exchange coupled (JCD) to one end of the trin...
VHF/UHF radiowave propagation through forests: modelling and experimental observations

A forest-propagation model has been developed which includes the effects of trunks, branches, leaves and the ground. This model represents the forest as a planar, stratified, anisotropic, discrete, random medium, bounded above by air and below by ground. The mean field of the propagating wave has been obtained by recognising that the ensemble of discrete scatterers can be replaced by an equivalent continuous medium characterised by a linear dyadic permittivity. Fourier-transform techniques have been employed to generalise the model so that it accommodates arbitrarily modulated waveforms. Comparison of the model predictions with experimental data are presented for typical forest parameters. The paper also discusses predicted values of transmission loss as they relate to distance, antenna height, frequency, polarisation and biophysical forest parameters.
Psychological studies of stress ulcer in the rat

The behavioral animal models of stress ulcer in the rat include immobilization, conflict, predictability, coping and avoidance responding. Research with these ulcer techniques is briefly reviewed. The activity-stress ulcer model is described and recent findings summarized. Physiological investigations of stress ulcer have produced considerable information regarding the proximal causes of ulcer disease. Behavioral scientists can make significant contributions to the study of stress ulcer by evaluating predisposing variables and by observing the relevant precipitating environmental events which lead to ulcer development.
The Influence of Farm Size on Gendered Involvement in Crop Cultivation and Decision-making Responsibility of Moldovan Farmers

This research describes the influence that farm size has on gendered involvement in crop cultivation and decision making about what crops to grow where, irrigation and marketing among small and medium-sized farmers in Moldova. Findings reveal that overall crop cultivation is characterized by gendered patterns that vary according to farm size. Overall men have much more input into decision making than do women but women on small farms have more input in decisions than do the women on medium-sized farms. However, women on medium-sized farms are more involved in the diverse range of cultivation activities in terms of labour.
Identification of Skin as a Major Site on Prostaglandin D2 Release Following Oral Administration of Niacin in Humans

Oral administration of niacin (nicotinic acid) at pharmacologic doses that reduce serum cholesterol levels induces intense flushing in humans. We have recently shown that the vasodilation following ingestion of niacin is due to the release of prostaglandin (PG) D2. However, the site from which PGD2 is released is not known. It has previously been shown that topical application of methylnicotinate causes local cutaneous erythema. Thus, we investigated whether topical methylnicotinate causes a release of PGD2 locally from skin and the possibility that skin may be a major contributor to the release of PGD2 when niacin is administered by mouth. Topical administration of methylnicotinate (10(-1) M) to the forearms of human volunteers resulted in 58- to 122-times increases in levels of PGD2 and 25- to 33-times increases in levels of the metabolite of PGD2, 9 alpha,11 beta-PGF2, in blood drawn from the antecubital vein draining the treated sites. Increased levels of PGD2 and 9 alpha,11 beta-PGF2 were not found in blood drawn simultaneously from veins in the contralateral arm, indicating that the PGD2 was released from the site of methylnicotinate application. The release of PGD2 in response to topically applied methylnicotinate occurred in a dose-dependent manner over the concentration range of 10(-3) to 10(-1) M. The release of PGD2 was not accompanied by a release of histamine, suggesting that the release of PGD2 was not from the mast cell. Following oral ingestion of niacin, levels of PGD2 in superficial venous blood draining the skin were 14 to 1200 times higher than the level in arterial blood supplying the skin of the same arm. This finding indicates that the skin is a major site from which PGD2 is released following oral ingestion of niacin. These studies thus indicate that the cutaneous vasodilation that occurs following oral administration of niacin is primarily due to a release of PGD2 from a niacin responsive cell that resides in the skin.
Properties of an encephalitogenic canine parainfluenza virus.

An isolate of canine parainfluenza (CPI) virus from the cerebrospinal fluid of a dog with neurological dysfunction was characterizedin vitro in comparison to a prototype strain of CPI virus, D008. The virus, designated 78–238 was found to be antigenically related to CPI virus (Manhatten strain) and simian virus 5 (SV5), but not to mumps virus (Enders strain). Ultrastructural observation of gradient-purified 78–238 virus revealed enveloped pleomorphic virions with helical nucleocapsid symmetry. Preliminary pathological studies indicated that 78–238 virus was encephalitogenic for gnotobiotic dogs when inoculated by the intracerebral route.
FRET-based glucose monitoring for bioprocessing

The glucose-mediated conformational changes in the glucose binding protein (GBP) have been exploited in the development of fluorescence based glucose sensors. The fluorescence response is generated by a polarity sensitive dye attached to a specific site. Such fluorescent sensors respond to submicromolar glucose at diffusion-controlled rates mimicking the wild type. However, such sensors have been limited to in vitro glucose sensing because of the preliminary dye-labeling step. In the study described here, the dye-labeling step is omitted by genetically encoding the GBP with two green fluorescent mutants namely, the green fluorescent protein (GFP) and the yellow fluorescent protein (YFP) in the N- and C-terminal ends, respectively. These two GFP mutants comprise a fluorescence resonance energy transfer (FRET) donor and acceptor pair. Thus, when glucose binds with GBP, the conformational changes affect the FRET efficiency yielding a dose-dependent response. A potential application for this FRET-based glucose biosensor is online glucose sensing in bioprocessing and cell culture. This was demonstrated by the measurement of glucose consumption in yeast fermentation. Further development of this system should yield in vivo measurement of glucose in bioprocesses.
Distortions in speech enhancement due to block processing

In most speech enhancement algorithms, a frequency response is computed per each block, and a multiplication in the frequency domain is used to apply this frequency response. Typically, in these algorithms, the updating procedure cannot ensure the fulfillment of the condition to perform a linear convolution instead of a circular convolution. As a result, artifacts and distortions may be present. Standard methods to deal with these distortions use overlapping and windowing. This work presents a detailed analysis of these distortions and proposes a new method to perform a artifact-free and distortion-free convolution in the FFT domain.
Risk and protective factors for pregnant women experiencing psychological abuse

A community sample of two hundred pregnant women reported on their experiences of psychological abuse, depressive symptoms, and emotional support. Findings indicated that prenatal depressive symptoms mediated the relationship between prenatal severity of psychological abuse and postpartum depressive symptoms. In addition, prenatal emotional support moderated the relationship between the severity of prenatal psychological abuse and prenatal depressive symptoms. Emotional support, therefore, was considered to act as a buffer for psychological abuse severity, as high levels of emotional support were associated with lower levels of depressive symptoms under conditions of more severe psychological abuse. These results were over and above the effects of the physical violence that these women experienced. Implications for research and practice are discussed.
Thermodynamic Properties of Ketenes: Group Additivity Values from Quantum Chemical Calculations

The geometries and thermodynamic properties (ΔHf298, S298, and Cp(T) (300−1500 K)) of 45 ketenes of four different types namely alkylketenes (set I), oxygenated alkylketenes (set II), 1,2- and 1,3-...
The role of the Josephson-Anderson equation in superfluid helium

This article explains how a simple equation describing the time evolution of a superfluid's quantum phase can be used as a powerful tool to rapidly deduce exact magnitudes of physical observables in situations involving very complex vortex motion. The equation has been used to simplify the understanding of new phenomena, such as vortex precession. Applications of the equation have also led to solutions of long-standing problems, such as the nucleation of vortices, and to new technology, such as the superfluid gyroscope. The article begins by presenting some basic ideas of superfluidity. This discussion leads to the concept of the quantum phase of the superfluid state and to the prediction that vorticity is quantized. Next a discussion is presented of the phase evolution equation, introduced by Josephson and developed further by Anderson. The utility of the equation is demonstrated by making certain general predictions about the consequences of vortex motion. Two experiments, one in ${}^{3}\mathrm{He}$ and another in ${}^{4}\mathrm{He},$ are then described in the context of the phase evolution equation. In the first, the precession frequency of a single vortex filament is easily explained in the context of the equation. In the second, quantized dissipation processes are observed which give detailed information about the creation of quantized vortices. The article concludes by showing how these latter experiments have led to the development of a superfluid sensor of absolute rotation. Although the article focuses on results emerging from the author's own laboratory, the footnotes lead the reader to some of the parallel ongoing projects, especially in the case of the ${}^{4}\mathrm{He}$ research at Orsay/Saclay in France, the University of Minnesota, and the University of Trento, Italy.
Bovine Pituitary Pyrrolidonecarboxylyl Peptidase

An enzyme has been obtained from bovine pituitary tissue which hydrolyzes L-pyrrolidonecarboxylyl- L-alanine, but not L-glutamyl-Lalanine. The enzyme was identified in whole pituitary homogenates, in 100,000 × g supernatant fraction of whole pituitaries and in anterior pituitary homogenates. After partial purification by ammonium sulfate precipitation and gel filtration, the enzyme was found to have a Km of 2.3 × 10–4M and to have maximal activity at pH 7.3. Like the Pseudomonas fluorescens pyrrolidonecarboxylyl peptidase prepared by Doolittle and coworkers, this enzyme is sulfhydryl-dependent and unstable in solution, but may be stabilized ∧ with the inhibitor 2-pyrrolidinone. The pituitary enzyme has been shown to cleave L-2-pyrrolidone- 5-carboxylic acid from the NH2-terminal position of synthetic thyrotropin-releasing factor and thus may have a degradative function related to the regulatory system controlling release of thyroid-stimulating hormone from the anterior pituitary. Evidence has been obtaine...
LABOR MARKET SEARCH: AN EXPERIMENTAL STUDY

The theoretical results derived from models of economic search have implications which relate to the structure and performance of labor markets. Utilizing a series of laboratory experiments, we attempt to capture many of the features of workers' search and also the conditions under which labor markets operate. By varying certain of the experimental conditions, we are able to determine the searchers' responses to changes in the terms of unemployment insurance, to the existence of a minimum wage, and to different states of information about the underlying distribution of wages. In most cases the behavior of the searchers is consistent with that predicted by theory.
Biophysical analysis of influenza A virus RNA promoter at physiological temperatures.

Each segment of the influenza A virus (IAV) genome contains conserved sequences at the 5′- and 3′-terminal ends, which form the promoter region necessary for polymerase binding and initiation of RNA synthesis. Although several models of interaction have been proposed it remains unclear if these two short, partially complementary, and highly conserved sequences can form a stable RNA duplex at physiological temperatures. First, our time-resolved FRET analysis revealed that a 14-mer 3′-RNA and a 15-mer 5′-RNA associate in solution, even at 42 °C. We also found that a nonfunctional RNA promoter containing the 3′-G3U mutation, as well as a promoter containing the compensatory 3′-G3U/C8A mutations, was able to form a duplex as efficiently as wild type. Second, UV melting analysis demonstrated that the wild-type and mutant RNA duplexes have similar stabilities in solution. We also observed an increase in thermostability for a looped promoter structure. The absence of differences in the stability and binding kinetics between wild type and a nonfunctional sequence suggests that the IAV promoter can be functionally inactivated without losing the capability to form a stable RNA duplex. Finally, using uridine specific chemical probing combined with mass spectrometry, we confirmed that the 5′ and 3′ sequences form a duplex which protects both RNAs from chemical modification, consistent with the previously published panhandle structure. These data support that these short, conserved promoter sequences form a stable complex at physiological temperatures, and this complex likely is important for polymerase recognition and viral replication.
Exploring liquid metal plasma facing component (PFC) concepts—Liquid metal film flow behavior under fusion relevant magnetic fields

Abstract The use of fast moving liquid metal streams or “liquid walls” as a plasma contact surface is a very attractive option and has been looked upon with considerable interest over the past several years, both by the plasma physics and fusion engineering programs. Flowing liquid walls provide an ever replenishing contact surface to the plasma, leading to very effective particle pumping and surface heat flux removal. A key feasibility issue for flowing liquid metal plasma facing component (PFC) systems, pertains to their magnetohydrodynamic (MHD) behavior under the spatially varying magnetic field environment, typical of a fusion device. MHD forces hinder the development of a smooth and controllable liquid metal flow needed for PFC applications. The present study builds up on the ongoing research effort at UCLA, directed towards providing qualitative and quantitative data on liquid metal free surface flow behavior under fusion relevant magnetic fields.
Radar signature of disturbed soil for mine detection

A potential strategy for wide area airborne mine/minefield detection is to identify localized areas of soil that have been disturbed due to mine emplacement amidst the undisturbed soil. Disturbed and undisturbed soils are rough in varying degrees and this roughness affects the backscattering behavior at the microwave frequencies. We investigated the feasibility of using high-frequency radar (8-18 GHz) backscatter measurements to detect the residual surface disturbances caused by recent mine emplacement. Radar backscatter measurements from recently buried landmines were obtained at a government minefield data collection site. Case studies of radar backscatter from landmines buried in dirt and gravel for varying incident angles are presented. These results demonstrate that the surface roughness contrast between disturbed and undisturbed soils can be exploited to assist in mine detection operations. The maximum radar backscatter contrast between the disturbed and undisturbed soils was observed at normal incidence. The minimum contrast (radar backscatter crossover angle) occurred between 15 and 30 degree incident angles. These experimental results are shown to be consistent with rough surface scattering assumptions.
Factors associated with postoperative morbidity, reoperation and readmission rates after laparoscopic total abdominal colectomy for ulcerative colitis.

Aim The aim of this study was to evaluate factors affecting postoperative outcomes after laparoscopic total abdominal colectomy (TAC) with end ileostomy (EI) for ulcerative colitis (UC). Method Patients undergoing laparoscopic TAC/EI for severe UC/indeterminate colitis in our institution between 1998 and 2010 were retrospectively identified from a prospectively established database. Demographics, disease characteristics and perioperative outcomes were recorded. Associations between the 30-day postoperative outcome and patient-, disease- and treatment-related variables were assessed using univariate and multivariate logistic regression models. Results Two hundred and four patients (105 men, median age 35.5 years) were identified. The conversion rate was 4.4%. Median blood loss and operation time were 100 ml and 185 min. Length of hospital stay was 5.8 ± 4.4 days. Overall postoperative morbidity, reoperation and readmission rates were 40, 7 and 17%, respectively Preoperative treatment with high steroid doses was significantly associated with postoperative morbidity on multivariate analysis (P = 0.011). Univariate analysis showed that lower preoperative body mass index (BMI), haemoglobin, serum albumin level and pancolitis were associated with reoperation, of which a lower BMI (P = 0.043) was also independently significant on multivariate analysis. No specific factor was significantly associated with readmission. Conclusion Preoperative clinical deterioration is associated with an adverse outcome after laparoscopic TAC for UC.
Uptake of bacteriophage λ DNA in Escherichia coli by electroporation: An alternative to in vitro packaging

By using a high field strength DC pulse of 15 kV/cm and a pulse duration of 5 ms for the transfection of E. coli by bacteriophage λ DNA, we obtained efficiencies of 1.1 × 106 (pfu/μg bacteriophage λ, DNA). This represents a 100-fold improvement over the traditional CaCl2/heat shock method and is a viable alternative to the more costly in vitro packaging of recombinant bacteriophage λ DNA for the production of cDNA and genomic libraries.
Role of novel multidrug efflux pump involved in drug resistance in Klebsiella pneumoniae.

Background Multidrug resistant Klebsiella pneumoniae have caused major therapeutic problems worldwide due to the emergence of the extended-spectrum β-lactamase producing strains. Although there are >10 major facilitator super family (MFS) efflux pumps annotated in the genome sequence of the K. pneumoniae bacillus, apparently less is known about their physiological relevance. Principal Findings Insertional inactivation of kpnGH resulting in increased susceptibility to antibiotics such as azithromycin, ceftazidime, ciprofloxacin, ertapenem, erythromycin, gentamicin, imipenem, ticarcillin, norfloxacin, polymyxin-B, piperacillin, spectinomycin, tobramycin and streptomycin, including dyes and detergents such as ethidium bromide, acriflavine, deoxycholate, sodium dodecyl sulphate, and disinfectants benzalkonium chloride, chlorhexidine and triclosan signifies the wide substrate specificity of the transporter in K. pneumoniae. Growth inactivation and direct fluorimetric efflux assays provide evidence that kpnGH mediates antimicrobial resistance by active extrusion in K. pneumoniae. The kpnGH isogenic mutant displayed decreased tolerance to cell envelope stressors emphasizing its added role in K. pneumoniae physiology. Conclusions and Significance The MFS efflux pump KpnGH involves in crucial physiological functions besides being an intrinsic resistance determinant in K. pneumoniae.
A Calculator for Two-Element Directive Arrays

This article describes a mechanical device which may be used to calculate quickly the horizontal field pattern of a two-element directive array. The construction is not difficult and may readily be undertaken with only the usual drafting instruments, a protractor, and a set of mathematical tables.
Flexible exchange rates, inflation and economic development

Abstract Different economies have different propensities to generate inflationary pressures, and different capacity to absorb the strains occasioned by price and wage increases. Because of economic and institutional features of less developed countries, expansionary policies may have to be undertaken in a ‘typical” developing country, more often and to a greater extent than in a ‘typical’ developed country. Even a mild rate of inflation will be damaging under a fixed-exchange-rate system, if domestic prices increase at a faster pace than prices abroad. Chronic balance-of-payments difficulties are confronted by inflationary countries that are attached to a fixed-exchange-rate system. Rather than sporadic, substantial devaluations, periodical mini-devaluations may be advisable in developing countries with a relatively high propensity to inflate.
Attachment Theory As Applied to Wartime and Job-Related Marital Separation

Research on wartime, long routine, and short routine marital separation is reviewed, with focus on spouses' distress, coping, and reunion reactions. Spouses' reactions are interpreted from the perspective of J. Bowlby's (1969) attachment theory (a) to illustrate similarities in spouses' reactions across different types of separation experiences, which argue for an integration of research in this field within a single conceptual framework; (b) to illustrate underlying similarities in separation reactions of adults and children, which further legitimize current extrapolations of attachment theory to adults; and (c) to conceptualize the differential reactions of home-based and traveling spouses, thereby extending attachment theory as it applies to adult romantic relationships. It is argued that a more comprehensive approach to the study of love and intimacy in adulthood requires attention to both the attachment and the caregiving systems.
Effect of the U.S. Embargo and Economic Decline on Health in Cuba

This article describes the ways in which economic crisis and the U.S. embargo have affected Cuba's health care system during the past 15 years. With the demise of subsidized trade, the absence of aid from the former Soviet Union, and the progressive tightening of U.S. sanctions, Cuba's model health care system has become threatened by serious shortages of medical supplies. Several public health catastrophes have occurred, including an epidemic of blindness that was partially attributed to a dramatic decrease in access to nutrients; an outbreak of the Guillain-Barre syndrome caused by lack of chlorination chemicals; and an epidemic of lye ingestion in toddlers due to severe shortages of soap. The policy of mandatory quarantine for HIV-infected Cubans has evolved into a less rigid system. Although the prevalence of HIV infection in Cuba is low compared with that in the United States and other Caribbean nations, it is threatened by prostitution, which has increased along with tourism. In general, economic sanctions may have an unintended but profound effect on the health and nutrition of vulnerable populations.
Androgens, lipids, and cardiovascular risk.

Excerpt The incidence of coronary artery disease is significantly higher in men than in women until menopause, after which the incidence of coronary disease is similar in both sexes. Most commonly,...
Release of gonadotrophin-releasing hormone (Gn-RH) from isolated, perifused medial-basal hypothalamus by melatonin.

Basal release of Gn-RH from perifused medial-basal hypothalami of rats was at or below levels detectable by radioimmunoassay. Infusion of norepinephrine, dopamine, acetylcholine or serotonin (0.1–10 mM) as 10–20 min pulses was not associated with a detectable increase of Gn-RH in the effluent. However, 10–20 min pulses of melatonin (0.1–1.0 mM) consistently caused release of Gn-RH.
Membrane Traffic: The Exocyst Meets the Cell Cycle

A new study describes a novel regulatory event that results in the inhibition of exocytic transport of a specific class of Golgi-derived vesicles during mitosis. The mechanism of inhibition is shown to involve direct phosphorylation of a subunit of the exocyst by a specific cyclin-dependent kinase complex.
Aluminium alkyl and aryloxide complexes of pyrazine and bipyridines: synthesis and structure.

The reaction of AlMe3 and [(tBu)2Al(μ-OPh)]2 with pyrazine (pyz), 4,4′-bipyridine (4-4′-bipy), 1,2-bis(4-pyridyl)ethane (bpetha) and 1,2-bis(4-pyridyl)ethylene (bpethe) yields (Me3Al)2(μ-pyz) (1), (Me3Al)2(μ-4,4′-bipy) (2), (Me3Al)2(μ-bpetha) (3), (Me3Al)2(μ-bipethe) (4), Al(tBu)2(OPh)(pyz) (5), [(tBu)2Al(OPh)]2(μ-4,4-bipy) (6a), [(tBu)2Al(OPh)]2(μ-bpetha) (7a), [(tBu)2Al(OPh)]2(μ-bipethe) (8a). Compounds 1–4, 6a and 7a have been confirmed by X-ray crystallography. In solution compounds 1–4 undergo a rapid ligand-dissociation equilibrium resulting in a time-average spectrum in the 1H NMR. In contrast, the solution equilibria for compounds 5–8a are sufficiently slow such that the mono-aluminium compounds may be observed by 1H NMR spectroscopy: Al(tBu)2(OPh)(4,4-bipy) (6b), Al(tBu)2(OPh)(bpetha) (7b) and Al(tBu)2(OPh)(bpethe) (8b). The inability to isolate [(tBu)2Al(OPh)]2(μ-pyz) and the relative stability of each complex is discussed with respect to the steric interactions across the bridging ligand (L) and the electronic effect on one Lewis acid–base interaction by the second Lewis acid–base interaction on the same ligand.
Observations of 3-m auroral irregularities during the ERRRIS campaigns

In the late winter of 1988 and 1989, three NASA sounding rockets were flown through the auroral electrojet from ESRANGE (Sweden) as part of the E-region Rocket-Radar Instability Study (ERRRIS). Many ground-based instruments supported these flights, including the EISCAT, STARE, and CUPRI radars, as well as all-sky cameras, riometers, and magnetometers. In this paper the observations of the Cornell University Portable Radar Interferometer (CUPRI), which detected coherent backscatter from 3-m irregularities in the auroral E-region are summarized. Twenty hours of power spectra and interferometry data are available, and, during the 1989 campaign, three weeks of nearly continuous Range-Time-Intensity (RTI) and first moment data were recorded.
Low-Dispersion Turns and Junctions for Microchannel Systems

Numerical methods are employed to optimize the geometry of two-dimensional microchannel turns such that the turn-induced spreading of a solute band is minimized. An inverted numerical method is first developed to compute the electric potential and local species motion in turns of arbitrary geometry. The turn geometry is then optimized by means of a nonlinear least-squares minimization algorithm using the spatial variance of the species distribution leaving the turn as the object function. This approach yields the turn geometry producing the minimum possible dispersion, subject only to prescribed constraints. The resulting low-dispersion turns provide an induced variance 2−3 orders of magnitude below that of a comparable conventional turns. Sample results are presented for 180 and 90° turns, and the use of these turns to form wyes and tees is discussed. A sample 45° wye is presented. The use of low-dispersion turns in folding separation columns is also discussed, and sample calculations are presented for f...
Screening for Type 2 Diabetes in Children With Acanthosis Nigricans

Acanthosis nigricans is a physical finding of the skin that appears to be a marker for insulin resistance. Because of the association of insulin resistance and type 2 diabetes, acanthosis nigricans may also be a marker for type 2 diabetes. Some states have recommended statewide screening for acanthosis nigricans. However, this has led to a large referral of children to pediatric endocrinologists. Presented is a schema for primary care physicians and school nurses to use as a guideline for referral of children with acanthosis nigricans.
Metabolic function of the CTRP family of hormones

Maintaining proper energy balance in mammals entails intimate crosstalk between various tissues and organs. These inter-organ communications are mediated, to a great extent, by secreted hormones that circulate in blood. Regulation of the complex metabolic networks by secreted hormones (e.g., insulin, glucagon, leptin, adiponectin, FGF21) constitutes an important mechanism governing the integrated control of whole-body metabolism. Disruption of hormone-mediated metabolic circuits frequently results in dysregulated energy metabolism and pathology. As part of an effort to identify novel metabolic hormones, we recently characterized a highly conserved family of 15 secreted proteins, the C1q/TNF-related proteins (CTRP1-15). While related to adiponectin in sequence and structural organization, each CTRP has its own unique tissue expression profile and non-redundant function in regulating sugar and/or fat metabolism. Here, we summarize the current understanding of the physiological functions of CTRPs, emphasizing their metabolic roles. Future studies using gain-of-function and loss-of-function mouse models will provide greater mechanistic insights into the critical role CTRPs play in regulating systemic energy homeostasis.
Decision support systems research: Reference disciplines and a cumulative tradition

Abstract This study applies factor analysis of an author cocitation frequency matrix derived from a database file consisting of a total of 15,030 cited reference records taken from 692 citing articles. Seven informal clusters of decision support systems (DSS) research subspecialties and reference disciplines were uncovered. Four of them represent DSS research subspecialties—foundations, group DSS, model/data management, and individual differences. Three other conceptual groupings define the reference disciplines of DSS—organizational science, multiple criteria decision making, and artificial intelligence. DSS is a very young academic field and is still growing. DSS has just entered the era of growth after 20 years of research. During the 1990s, DSS research will be further grounded in a diverse set of reference disciplines. Furthermore, DSS is in the active process of solidifying its domain and demarcating its reference disciplines. A DSS theory is imminent in the very near future in some area of DSS research such as model management.
Relationship of a large weight loss to long-term weight change among young and middle-aged US women

OBJECTIVE: To assess the prevalence of clinically significant weight loss among women and whether this is associated with smaller long-term weight gains. DESIGN: Six-year follow-up of young and middle-aged women in the Nurses' Health Study II. SUBJECTS: A total of 47 515 women who did not report a pregnancy, or a diagnosis of cancer or cardiovascular disease any time between 1989 and 1995. MEASUREMENTS: Self-reported weights in 1989, 1991, 1993 and 1995, dietary intake, physical activity, inactivity, history of weight cycling and smoking. RESULTS: Between 1989 and 1991, 9% of the women lost ≥5% of their 1989 weight (6% lost 5–9.9% and 3% lost ≥10%). The proportion who lost ≥10% of their weight increased with category of body mass index (BMI, kg/m2) from 0.4% among women with a BMI <22 to 9% among women with a BMI ≥30 in 1989. Women who lost ≥5% of their weight between 1989 and 1991 gained more weight between 1991 and 1995 than their peers and the difference increased across categories of BMI in 1989. However, due to their large weight losses, women who lost ≥5% of their weight between 1989 and 1991 overall gained less weight than their peers between 1989 and 1995 (P<0.001). Moreover, women who engaged in 5 or more hours per week of vigorous physical activity gained approximately 0.5 kg less than their inactive peers (P<0.001). CONCLUSION: Although most women who lost a clinically significant amount of weight regained most of it, they gained less weight over the entire 6 y period than their peers.
Autoradiographic localization and characterization of [125I]lysergic acid diethylamide binding to serotonin receptors in Aplysia.

Abstract The sensitive serotonergic radioligand 2-[ 125 I]lysergic acid diethylamide was used to study the distribution and pharmacological binding properties of serotonin receptors in Aplysia californica . The high specific activity of this radioligand allowed us to develop a methodology for the investigation of receptor binding properties and receptor distribution in a single ganglion. [ 125 I]Lysergic acid diethylamide labels a population of high-affinity serotonergic sites (K d = 0.41nM) in Aplysia ganglia whose regional distribution matches that expected from previous electrophysiological and immunohistochemical studies. The properties of [ 125 I]lysergic acid diethylamide binding sites in Aplysia are in general agreement with previous studies on [ 3 H]lysergic acid diethylamide binding in this system but these sites differ from the serotonergic receptor subtypes described in the mammalian brain. Guanine nucleotides were shown to modulate agonist but not antagonist affinity for the [ 125 I]lysergic acid diethylamide binding site in Aplysia , suggesting that this site is coupled to a G-protein. Images of serotonin receptor distribution in the Aplysia nervous system were obtained from auto-radiograms of [ 125 I]lysergic acid diethylamide binding. Serotonin receptors in ganglia tissue sections are located primarily within the neuropil. In addition, a subset of neuronal soma are specifically labeled by [ 125 I]lysergic acid diethylamide. These studies indicate that [ 125 I]lysergic acid diethylamide binds to sites in the Aplysia nervous system which display a regional distribution, pharmacological binding properties and evidence of coupling to a G-protein consistent with labeling of a subset of functional serotonin receptors. In addition, the techniques used in this investigation provide a general approach for rapidly characterizing the pharmacological properties and anatomical distribution of receptor binding sites in single invertebrate ganglia. Individual neurons containing these receptor subtypes can be identified by these methods and correlated with physiological responses in the same cell.
An assessment of the wind-energy utilization potential in tennessee, USA

Abstract For five locations in Tennessee (Chattanooga, Knoxville, Memphis, Nashville, and the Tri-Cities conurbation of Bristol, Johnson City, and Kingsport), estimates have been obtained of available wind-power density, energy output from a specified wind-driven electricity-generating system, and unit cost of the electricity produced by this system. The best results are obtained for Memphis. Notwithstanding this observation, it is shown that the use of wind energy for electricity generation is not an economically-viable option at any of the locations considered.
On the intracellular distribution of [4-14C]cortisol in rat liver

Abstract In the experiments reported here, it is hoped that an approach to eventual understanding of the role of cortisol in the liver can be made through separation of possible complexes formed by cortisol in the cell. 1. 1. Intraperitoneal and intravenous injections of [4-14C]cortisol (2 μC and 0.25 μC respectively) showed the label to be distributed in the microsomes, the supernatant fraction, and to a lesser extent, the mitochondria, in rat liver. High concentrations of the label in these fractions could be found as early as 30 sec after the intravenous injections. 2. 2. The peaks in the percentage supernatant values at 4 and 7 min, followed by a continual rise in the value after 7 min, suggest that the label passes over to a second supernatant step, from the first supernatant step, or from the microsomes, or both. 3. 3. A set of experiments in which a pulse of [14C]cortisol was followed by a chase of unlabeled cortisol gave results which indicated two types of attachment of the label to the microsomes in the first step. Ether extraction, electrophoresis and the pulse-labeling experiments, all suggest the lack of exchangeability of the labeled substance in the supernatant fractions and the stability of its binding to this fraction. 4. 4. In a series of intravenous injections of [14C]cortisol in male and female adrenalectomized rats, it was shown that the cortisol distribution in adrenalectomized male rats was different from that in the female rats, suggesting the possibility that normal “cortisol activity” in the two sexes is different. 5. 5. In experiments where the injected quantities of label varied from very small (0.2 μg) to larger (inducing) amounts (2.5 mg), the distribution of the label was found to be very similar to that obtained with the 0.25 μC (2.0 μg) experiments.
Stress-Induced Dichroism and Energy Shifts in the A , B , and C Absorption Bands in KCl: Tl

The effects of uniaxial stress on the $A$, $B$, and $C$ absorption bands of KCl: Tl are determined using a static and dynamic Jahn-Teller interaction. The uniaxial stress alters the local symmetry giving rise to preferred spacial directions which, in turn, causes dichroism in the observed absorption spectra. The dynamic interaction accounts for the "time-average" splitting of energy levels which manifests itself by causing shifts in the band peaks. A calculation of the polarization effects and the shifting of the energy levels is carried out for the cases of [001] and [110] uniaxial stress. This is accomplished by (a) determining the transition probabilities for transitions from the $6{s}^{2}$ ground state to the $6s6p$ excited state of ${\mathrm{Tl}}^{+}$ in both ${D}_{4h}(001)$ and ${D}_{2h}(110)$ environments and (b) determining the excited-state eigenenergies in terms of the interaction modes characterized by the above symmetries. The results are shown to compare favorably with recent available experimental results. Several theoretical conclusions are reached which await experimental verification.
Solitary benign parietal lesions seen on CT in cancer patients

Benign skull lesions are routinely encountered in clinical practice. The aim of this review is to describe the Computed tomography (CT) findings of solitary benign parietal lesions. Benign parietal bone lesions can exist in patients with history of cancer. Metastasis to the calvarium is rare compared to other sites in the body and primary skull tumors are even rarer. This is the second report of solitary cholesteatoma occurring in the parietal bone. All the clinical cases in this study were histologically proven. Benign solitary parietal lesions can have non-specific features on CT and in some cases, only biopsy can give a definite diagnosis.
Operations planning with real time pricing of a primary input

Abstract We examine the problem of planning the operation of an air separation plant where the price of its primary production input, electricity, changes hour to hour, a situation commonly referred to as real time pricing (RTP). We present a solution approach where operating decisions are obtained from optimizing a mixed integer program embedded in a rolling horizon procedure. A simulation study is conducted to assess the effect of unreliable and finite information on the efficiency of the operations plans generated by the procedure. Results of the study suggest that the rolling horizon procedure generates robust plans. An additional simulation study is conducted to identify the conditions under which RTP is attractive vis-a-vis other selected electricity pricing schemes. Results of the study indicate that RTP is most appealing when there is substantial flexibility in the operating environment in terms of the load placed on the plant (customer demand) and with regard to ramp-up (akin to set-up) times. Although this appeal diminishes with increased loads and longer ramp-ups, it is nevertheless the case that the operational inflexibility must be significant before RTP loses its allure. Scope and purpose: This paper considers the plant operation problem faced by firms in the industrial gas industry with production facilities where the price of the primary production input, that is electricity, changes hour to hour, which is often referred to as real time pricing. The purpose of this work is to present an optimization based planning approach that rigorously takes into account the realities of this environment. In addition this work seeks to identify, through the use of simulation, the conditions under which real time pricing is most appealing vis-a-vis other electricity pricing schemes, and also the degree to which planning horizon length and uncertainty in electricity prices impact the efficiency of the operations plans generated by our planning approach.
Animal cognition: Monkeys pass the mirror test

A new study finds that rhesus monkeys display self-recognition behaviors toward a mirror after multimodal sensory-motor training. This finding closes a prior gap in the evolutionary continuity of animal cognition and opens new frontiers for exploring the neurobiological basis of self-awareness.