cssi/SciSciGPT-SciSciNet huggingface dataset:
Cervical stroma apoptosis in pregnancy.

Objective: To determine whether the percentage of apoptotic nuclei is different in cervical stroma of pregnant laboring women compared with nonpregnant women and pregnant nonlaboring women. Methods: We took cervical stromal biopsies during cesarean delivery at the level of the lower uterine segment from ten women in active labor and 13 women before labor. In addition, we took biopsies of cervical stroma at the level of the internal cervical os from hysterectomy specimens in ten reproductive-aged women. Cryosections were then analyzed using terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling staining. Tissue specimens were analyzed with ligation-mediated polymerase chain reaction to visualize nucleosomal ladders characteristic of apoptosis. To detect a 10% difference in the percentage of apoptotic cells per subject between study groups assuming a power of 0.90, an alpha of .05 in approximately ten subjects per group was needed. Results: The median percentage of apoptotic nuclei was 0.7 (interquartile range 0.4, 1.4) for the nonpregnant group, 7.5 (interquartile range 6.6, 11.2) for the pregnant nonlaboring group, and 11.6 (interquartile range 8.3, 16.7) for the pregnant laboring group (P < .001). The percentage of apoptotic nuclei differed significantly across the three study groups. Using ligation-mediated polymerase chain reaction, nucleosomal ladders were seen in the specimens from pregnant women but not in the specimens from nonpregnant women, confirming the increase in stromal apoptosis seen with pregnancy. Conclusion: Apoptosis of cervical stromal cells may play a role in the remodeling of the cervix during pregnancy and contribute to cervical changes during labor.
Religious Persecution: And What To Do About It

Hinduism, Islam, Christianity, Buddhism, and other religions can all be found in geographically diverse Indonesia. Adding to this layered society are many different ethnic groups, political groups, and socio–economic groups. The joining of all these factors led to different communities forming adats–religio–customary agreements. When talking about “religious persecution” in Indonesia, all of these factors must be taken into account. Even so, it would be extremely naive to think that religious belief is a peripheral motivation for violence. This article explores a method by which religious scholars, leaders, and communities can curtail religious persecution in Indonesia; the method includes: personal encounter; discussion of the scholarly agenda; a public engagement through dialogue that leads to commitment; and finally, the appeal of prayer and ritual.
Sound‐generating (sonic) motor system in a teleost fish (Porichthys notatus): Sexual polymorphisms and general synaptology of sonic motor nucleus

The sonic motor nucleus of the plainfin midshipman, Porichthys notatus, is a midline nucleus located at the junction of the caudal medulla and rostral spinal cord. Its motoneurons innervate sonic "drumming" muscles that are attached to the lateral walls of the swimbladder. There are two classes of sexually mature males referred to as Type I and Type II. The Type I males are larger and generate sounds during the breeding season. The Type II males are smaller and, like adult females, have not yet been shown to generate sounds. This study examined possible sex differences in the size of sonic motoneurons, and the type and distribution of their afferent terminal boutons. The average soma diameter of motoneurons of Type I males is about 50% larger than that of Type II males and females. There is also a small but significant difference in soma diameter between Type II males and females; they are smaller in the former class. There were no sex differences in the presence or distribution of different classes of axosomatic and axodendritic terminal boutons, which included: (1) active zones with either clear, round, or pleomorphic vesicles, (2) active zones with both clear, round vesicles, and larger dense core vesicles, (3) "mixed synapses" with gap junctions and active zones usually associated with pleomorphic vesicles. The results are discussed within the context of sexual differentiation of vertebrate motor systems and the functional organization of the sonic motor system in fishes. Sex differences in soma diameter correlate with a number of sex differences in the gross and ultrastructural features that distinguish the sonic muscles of Type I males from those of Type II males and females, which are similar to each other. The absence of qualitative sex differences in synaptic morphology suggest that the central neuronal circuitry of the sonic motor system is similar among all three adult morphs.
The Transcription Factor Snail Mediates Epithelial to Mesenchymal Transitions by Repression of Estrogen Receptor-α

The estrogen receptor (ER)-α (ESR1) is a key regulatory molecule in mammary epithelial cell development. Loss of ER-α in breast cancer is correlated with poor prognosis, increased recurrence after treatment, and an elevated incidence of metastasis. A proposed molecular pathway by which ER-α acts to constrain invasive growth in breast cancer cells involves direct, ER-α-dependent expression of metastasis-associated protein 3, a cell-type-specific component of the Mi-2/NuRD chromatin remodeling complex. MTA3 in turn represses expression of Snail, a transcription factor linked to epithelial to mesenchymal transition and cancer metastasis. To elucidate its role(s) in epithelial to mesenchymal transition (EMT), we expressed Snail in the noninvasive, ER-α-positive MCF-7 cell line. Snail expression led to decreased cell-cell adhesion and increased cell invasiveness. Furthermore, we observed loss of ER-α expression at both the RNA and protein level that was accompanied by direct interaction of Snail with regulator...
"Extraoperative" MRI (eoMRI) for Brain Tumor Surgery: Initial Results at a Single Institution.

Background There is accumulating evidence that extent of resection (EOR) in intrinsic brain tumor surgery prolongs overall survival (OS) and progression-free survival (PFS). One of the strategies to increase EOR is the use of intraoperative MRI (ioMRI); however, considerable infrastructure investment is needed to establish and maintain a sophisticated ioMRI. We report the preliminary results of an extraoperative (eoMRI) protocol, with a focus on safety, feasibility, and EOR in intrinsic brain tumor surgery. Methods Ten patients underwent an eoMRI protocol consisting of surgical resection in a conventional operating room followed by an immediate MRI in a clinical MRI scanner while the patient was still under anesthesia. If findings of the MRI suggested residual safely resectable tumor, the patient was returned to the operating room. A retrospective volumetric analysis was undertaken to investigate the percentage of tumor resected after first resection and if applicable, after further resection. Results Six of 10 (60%) patients were thought to require no further resection after eoMRI. The EOR in these patients was 97.8% ± 1.8%. In the 4 patients who underwent further resection, the EOR during the original surgery was 88.5% ± 9.5% ( P = 0.04). There was an average of 10.1% more tumor removed between the first and second surgery. In 3 of 4 (75%) of patients who returned for further resection, gross total resection of tumor was achieved. Conclusion An eoMRI protocol appears to be a safe and practical method to ensure maximum safe resections in patients with brain tumors and can be performed readily in all centers with MRI capabilities.
Canonized Women and Women Canonizers: Gender Dynamics in The Norton Anthology of English Literature ’s Eight Editions

This article addresses the gender dynamics of the included canonized literature of each edition of the Norton Anthology of English Literature as related to the gender dynamics of the editorial staff, the publication date of each of the eight editions, and the feminist criticism prominent at the time of publication. The project combines quantitative and qualitative methods to examine the construction of the literary canon. The project finds that there is a direct correspondence between the number of women editors and the percent of the total pages of each edition occupied by works by women writers. The project also finds a correlation between the gender makeup of the editorial staff and a leap in included women writers in the fifth edition and the emergence of gynocriticism in the 1980s. The project recognizes the establishment of a separate canon for women’s literature that corresponds with this shift. The research indicates that as time passes, the inclusion of women writers in the literary canon and the editorial staff of the Anthology generally increase.
All things in moderation.

It is unfortunate that Dr. Blackburn and his colleagues interpreted the editorial, "Cheers!," as a blanket recom mendation for "regular moderate drinking at any age." In their letter, they did, however, acknowledge the need for "reexamining society's drinking attitudes and practices for modifications that may enhance the public's health," which was the purpose of the editorial. I did not go into detail regarding the adverse effects of alcohol consump tion because the scientific community is already cogni zant of the huge costs to society of alcohol abuse. It is my opinion, however, that physicians and other scientists have been so overwhelmed by information about alcohol abuse that many are not aware of potentially beneficial aspects of moderate use. Even the Koran attributes "benefits" as well as "costs" to the use of alcoholic beverages. Islam has deemed that the costs exceed the benefits, and thus the consumption of alcohol is prohibited for the faithful. It may well be that the costs to many societies greatly outweigh any potential benefits. In most of the industrialized countries today, however, and increasingly in the developing world, coronary artery disease is the leading cause of death. If there are indeed rather large potential benefits from alcohol in terms of reducing coronary disease, perhaps we are at a time when the costTbenefit aspects of moderate alcohol consumption by the population should be recon sidered. I disagree with Blackburn, Wagenaar, and Jacobs as to the strength of the current scientific evidence relating alcohol consumption to heart disease. Most cohort studies, case-control studies, intervention studies in humans, and animal experiments dealing with this topic have been remarkably consistent in their findings: Cardio vascular risk factors, measures of atherosclerosis, and rates of coronary artery disease are generally lower among humans or animals exposed to moderate amounts of alcohol. A number of authors have reviewed the available data in the literature and, while not "entering them into a formal meta-analysis," have commented on the remark able consistency of findings.1-4 As Blackburn and col leagues point out, there are many publications "in which the evidence is considered insufficient to support any real
A comprehensive molecular phylogeny of the starlings (Aves: Sturnidae) and mockingbirds (Aves: Mimidae): Congruent mtDNA and nuclear trees for a cosmopolitan avian radiation

We generated a comprehensive phylogeny for the avian families Sturnidae (starlings, mynas, Rhabdornis, oxpeckers, and allies) and Mimidae (mockingbirds, thrashers, and allies) to explore patterns of morphological and behavioral diversification. Reconstructions were based on mitochondrial DNA sequences from five coding genes (4108 bp), and nuclear intron sequences from four loci (2974 bp), for most taxa, supplemented with NDII gene sequences (1041 bp) derived from museum skin specimens from additional taxa; together the 117 sampled taxa comprise 78% of the 151 species in these families and include representatives of all currently or recently recognized genera. Phylogenetic analyses consistently identified nine major clades. The basal lineage is comprised of the two Buphagus oxpeckers, which are presently confined to Africa where they are obligately associated with large mammals. Some species in nearly all of the other major clades also feed on or around large vertebrates, and this association may be an ancestral trait that fostered the world-wide dispersal of this group. The remaining taxa divide into sister clades representing the New-World Mimidae and Old-World Sturnidae. The Mimidae are divided into two subclades, a group of Central American and West Indian catbirds and thrashers, and a pan-American clade of mockingbirds and thrashers. The Sturnidae are subdivided into six clades. The Phillipine endemic Rhabdornis are the sister lineage to a larger and substantially more recent radiation of South Asian and Pacific island starlings and mynas. A clade of largely migratory or nomadic Eurasian starlings (within which the basal lineage is the model taxon Sturnus vulgaris) is allied to three groups of largely African species. These reconstructions confirm that Buphagus should not be included in the Sturnidae, and identify many genera that are not monophyletic. They also highlight the substantial diversity among the major Sturnidae subclades in rates of species accumulation, morphological differentiation, and behavioral variation.
Atmospheric conditions in 1995 from the orbital decay of the oderacs ii spheres

Abstract The orbital decay of a low-Earth-orbit satellite having constant cross-sectional area in a near-circular orbit can furnish valuable information regarding the dynamical conditions of the atmosphere. The slope of the orbital decay curve gives the atmospheric density, whereas the curvature of the decay curve can indicate the expansion, stability or contraction of the atmosphere. The state of the atmosphere in 1994 was determined from the orbital decay of the ODERACS I spheres by employing this technique. The state of the atmosphere in 1995 was determined from the orbital decay of the ODERACS II spheres and reported in this study. From days 40–215, 1995, the atmosphere was in a prolonged compression mode. During this period, ODERACS II Sphere 3 encountered progressively smaller densities as the density scale height diminished steadily. This was followed by a period of relatively stable atmosphere. During a brief period from days 280–300, the atmosphere was in a strong expansion mode, which was followed by another compression mode until day 360. The results show great parallels between the atmospheric conditions in 1994 and 1995, including clear indications of the semi-annual variation. The atmosphere in 1995 was under greater compression than in 1994, consistent with the phase of the sunspot cycle. However, the rate of atmospheric contraction was greater in 1994 than in 1995 in contrast to predicted models. The observed 10.7 cm solar fluxes at Penticton, British Columbia, strongly support the findings of this study.
Adaptive online camera coordination for multi-camera multi-target surveillance

Online camera selection is introduced as a result of the improved mobility of cameras and the increased scale of surveillance systems. Most existing camera assignment algorithms achieve an optimal observation under the assumption of the unlimited camera computational capacities. However, practical surveillance systems experience resource limitation and see a degradation in the system performance as the number of objects to be processed increases. To address this issue, we propose an adaptive camera assignment algorithm considering the limited camera computational capacities. In so doing, camera resources can be dynamically allocated to multiple objects according to their priorities and the current camera computational load. Experimental results illustrate that the proposed camera assignment algorithm is capable of maintaining a constant frame rate and achieving a substantially decreased object rejection rate in comparison with the algorithm presented by Bakhtari and Benhabib.
Anomalies in MODFET's with a low-temperature buffer

GaAs buffer layers grown by molecular-beam epitaxy (MBE) at low temperatures (200-300 degrees C) have been successfully used to reduce sidegating in both MESFETs and MODFETs. There are, however, high concentrations of defects in the low-temperature (LT) buffers that adversely affect the high-frequency performance of precision analog and certain digital circuits. In unoptimized structures, nanosecond and microsecond transients are as large as 85 and 15% of the total voltage swing, respectively. These transients cause various detrimental effects in circuits. These effects are described. Their origin is attributed to the outdiffusion of defects from the LT buffer, and a method for optimizing the device structure for minimum sidegating and maximum high-frequency performance is presented. >
Frictionless contact of layered metal-matrix and polymer-matrix composite half planes

Abstract This paper examines the differences and similarities in the response of metal-matrix and polymer-matrix composite half planes indented by a rigid, parabolic punch. The quantities of interest are the load versus contact length and the normal stress distribution in the contact region. In particular, the effect of material properties and off-axis ply orientation on these quantities is investigated for homogeneous and layered configurations. Layered configurations include [0°/±45°] layer sequences bonded to 90° half planes, as well as to a half plane with significantly lower elastic stiffness moduli. The analysis is conducted using a recently developed solution method for frictionless contact problems of arbitrarily layered half planes consisting of isotropic, orthotropic, or monoclinic layers. The results indicate that homogeneous metal-matrix composite half planes exhibit a substantially stiffer load versus contact length response than homogeneous polymeric matrix half planes owing to their higher transverse material parameters, in particular the transverse Young's modulus, E33. In situations where local bending is present, which occurs in sandwich-type configurations with a substantially softer substrate, the ratio of the longitudinal to transverse Young's moduli plays a significant role for the considered laminate configurations. In this case, the normalized contact stress profiles of certain metal-matrix and polymer-matrix composites exhibit substantial departures from elliptical that appear similar in shape despite differences in the actual magnitudes of the material parameters.
Estrogen receptor alpha modulates toll-like receptor signaling in murine lupus

Systemic lupus erythematosus (SLE) is a disease that disproportionately affects females. Despite significant research effort, the mechanisms underlying the female predominance in this disease are largely unknown. Previously, we showed that estrogen receptor alpha knockout (ERαKO) lupus prone female mice had significantly less pathologic renal disease and proteinuria, and significantly prolonged survival. Since autoantibody levels and number and percentage of B/T cells were not significantly impacted by ERα genotype, we hypothesized that the primary benefit of ERα deficiency in lupus nephritis was via modulation of the innate immune response. Using BMDCs and spleen cells/B cells from female wild-type or ERαKO mice, we found that ERαKO-derived cells have a significantly reduced inflammatory response after stimulation with TLR agonists. Our results indicate that the inflammatory response to TLR ligands is significantly impacted by the presence of ERα despite the absence of estradiol, and may partially explain the protective effect of ERα deficiency in lupus-prone animals.
A general procedure for the manual sequencing of small quantities of peptides.

Abstract Modifications of the classical Edman cycle permitted the complete sequential degradation, without prior derivatization, of all small and medium-sized peptides with a free N-terminus. Sequences of up to 40 residues appeared possible with most long peptides. Quantities of 5–50 nmoles were optimal for the apparatus described. Cycling time was 50–90 min. Degradation was monitored and derivatives identified with a fast and sensitive thin-layer technique.
Meqalac RF Accelerating Structure

A prototype MEQALAC capable of replacing the Cockcroft Walton pre-injector at BNL is being fabricated. Ten milliamperes of H/sup -/ beam supplied from a source sitting at a potential of -40 kilovolt is to be accelerated to 750 keV. This energy gain is provided by a 200 Megahertz accelerating system rather than the normal dc acceleration. Substantial size and cost reduction would be realized by such a system over conventional pre-accelerator systems.
Steady-state and dynamic modeling for new product design for the solid-state polymerization of poly(ethylene terephthalate)

We model an entire poly(ethylene terephthalate) (PET) solid-state polymerization (SSP) process with precrystallizers, crystallizers, SSP reactors, and dryers using a unified cell approach. This approach builds complex unit-operation models using individual cells, or continuous-stirred-tank reactor (CSTR) models. Each cell considers the essential physical properties, phase equilibrium, polymerization kinetics, mass transfer through the polymer and into the carrier gas, and crystallization kinetics. Our model development involves fundamental chemical engineering principles and advanced software tools, such as Polymers Plus and Aspen Custom Modeler. We analyze both reaction and diffusion in each cell, considering two options: (1) to model diffusion using a second-order partial differential equation (PDE) or a simplified two-film theory and (2) to include or ignore crystallization kinetics. Performing best is the model with a PDE for diffusion and with equations describing crystallization and its effect on r...
Impact history of the Chelyabinsk meteorite: Electron microprobe and LA-ICP-MS study of sulfides and metals

Abstract Electron microprobe and LA-ICP-MS study of sulfides and metals from two fragments of the LL5 Chelyabinsk meteorite were conducted. The fragments are impact breccias, one fragment contains both chondritic and shock vein lithologies, and the other contains shock-darkened chondritic clasts and vesicular impact melts. The chondritic lithology and shock veins display very similar opaque mineral compositions. The mineral compositions in the impact-melt breccias are distinctly different. The brecciated state of the Chelyabinsk meteorite suggests strong involvement of shock-related processes during the evolution of the parent body. Multiple heavy impact events occurred on the parent asteroid and on the Chelyabinsk meteoroid itself over the time period from ca. 4.5 Ga until ca. 1.2 Ma. The shock veins were produced in situ on the parent body. The impact-melt breccias could have formed because of the dramatic impact to the parent LL-chondrite body that could be partly disintegrated. The fragment containing shock-darkened chondritic clasts and vesicular impact melt lithologies preserves a record of melting, volatilization, partial degassing, and quenching of the molten material. The abundance and size (up to 1 mm) of the vesicles suggest that the impact melt must have been buried at some depth after formation. After impact and subsequent melting occurred, the impact-induced pressure on the shallow asteroid interior was released that caused “boiling” of volatiles and generation of S-rich bubbles. Such an impact excavated down to depths of the body generating multiple fragments with complicated histories. These fragments reaccumulated into a gravitational aggregate and formed the parental meteoroid for the Chelyabinsk meteorite.
High-efficiency high-energy-resolution spectrometer for inelastic X-ray scattering

A nine-element analyzer system for inelastic X-ray scattering has been designed and constructed. Each individual analyzer crystal is carefully aligned with an inverse joystick goniometer. For the analyzers silicon wafers with 100 mm diameter are spherically bent to 1 or 0.85 m radius, respectively. Additionally, an analyzer with an extra small radius of 0.182 m and diameter of 100 mm was constructed for X-ray absorption spectroscopy in fluorescence mode. All analyzer crystals with large radius have highly uniform focusing property. The total energy resolution is approximately 0.5 eV at backscattering for the 1 m radius Si(440) analyzer array and approximately 4 eV for the 0.182 m radius Si(440) analyzer at 6493 eV.
Elevated sister chromatid exchange and cell cycle analysis in bone marrow in childhood ALL

Sister chromatid exchange (SCE) frequencies were analyzed in both stimulated and unstimulated bone marrow samples from eight patients recently found to have childhood acute lymphocytic leukemia (ALL). Six of the patients had elevated SCE frequencies in stimulated marrow when compared to control values. In unstimulated marrow, all four patients had elevated SCE frequencies. These data agree with peripheral leukocyte findings in ALL. Cell cycle analysis revealed no significant differences between the patient marrows and the control marrows. Since no correlation between cell cycle distribution and SCE frequency was found, it is suggested that the differences in SCE observed may be related to the type of proliferating cell.
Structure-activity relationship observations oftrans-trimedlure enantiomers

tert-Butyl 4- (and 5-) chloro-trans-2-methylcyclohexane-1-carboxylate (TML), a mixture of four majortrans and four minorcis isomers, is used as an attractant for detecting and monitoring the male Mediterranean fruit fly (medfly),Ceratitis capitata (Wiedemann). The eight isomers (racemic mixtures) were isolated by HPLC, and their relative attractiveness in the field was determined. A quantitative structure-activity relationship (QSAR) was proposed that related a molecular measurement (A3) of the TML structure to male medfly captures. More recently, thetrans-TML enantiomers were synthesized in sufficient quantities for field testing. This paper reports the computer-aided molecular modeling, via Chem-X, of thetrans-TML enantiomers and the staggered and superimposed fitting with the most attractive isomer, (1S,2S,4R)-TML-C, to determine common volumes and surface areas from Van der Waals (VdW) maps. Observations of structure-activity relationships (SAR) are reported for the staggered fittings.
Drug design as a video game: A summer program integrating chemical biology and computer science

Virtual drug screening is a rapidly evolving technique which offers great promise for the systematic evaluation of large chemical libraries to identify potential drug candidates. eHiTS Lightning is a commercial drug design software which takes advantage of the Cell Broadband Engine processor present in the video game console Sony PlayStation 3 to greatly accelerate computations. In the summer of 2008, a computational chemistry program for high school students was held at Rhode Island College which incorporated several different modules which combined biology, chemistry, and computer science. One of these modules focused on computer-aided drug design. Here, we describe the objectives, methods, achievements, and future goals of that aspect of the program where a high school student, mentored by a graduate student, used eHiTS Lightning on a Sony PlayStation 3 in order to identify molecules which may be potential cancer therapeutics.
Angiographic outcome of intracranial aneurysms with neck remnant following coil embolization

Background The degree of aneurysm occlusion following coil embolization has an impact on aneurysm recanalization. Objective To explain the natural history of intracranial aneurysms with neck remnant, Raymond–Roy Occlusion Classification (RROC) class II. Methods A single-center, retrospective study of 198 patients with 209 aneurysms treated with coil embolization that were initially either RROC class I or II. The angiographic outcomes at short- and long-term follow-up were compared as well as the complication/re-treatment rates. Atypical aneurysms and those that had been previously treated were excluded. Results Ninety-nine class I aneurysms were compared with 110 class II aneurysms. There was no difference in recanalization rate between the groups (class I 3.3% vs class II 8.5%, p=0.478) at short-term follow-up (8.2 months) and at subsequent follow-ups (21.7 and 52.1 months). There was also no difference in re-treatment rates (class I 3.3% vs class II 8.5%, p=0.196) or complication rates (class I 9.1% vs class II 4.6%, p=0.12). There were no aneurysm ruptures after treatment in either group. Conclusions The angiographic outcome of aneurysms with neck remnant following coil embolization is similar to that of completely occluded aneurysms in that most remain stable and few recanalize. This understanding could potentially help the interventional neurosurgeon avoid complications such as coil herniation, vessel compromise, and stroke in selected cases. Further investigation with a larger patient population is warranted.
Does firm size matter? Evidence on the impact of liquidity constraints on firm investment behavior in Germany

Abstract This paper examines the link between liquidity constraints and investment behavior for German firms of different sizes from 1970 to 1986. Results indicate that medium sized firms appear to be more liquidity constrained in their investment behavior than either the smallest or largest firms in the study, suggesting that the unique German infrastructure designed to assist the small firm has indeed succeeded in alleviating, to some degree, such liquidity constraints. Findings also support the hypothesis that the emerging competition and internationalism which characterized the German financial markets in the 1980s, have been improving access to capital for some groups of firms.
Culture of cardiac muscle cells in serum-free media

Abstract Cardiac muscle cells from neonatal rats have been cultured in completely defined serum-free media. The most successful system consists of precoating culture flasks with fibronectin at a concentration of 5 μg/cm2 of surface area and adding fetuin and either dibutyryl cyclic AMP (db-cAMP), cholera toxin, epidermal growth factor or insulin plus dexamethasone to the medium. In order to define a serum- and a hormone or growth factor-free medium, cardiac muscle cells were grown in the presence of fibronectin, fetuin and db-cAMP for 4 days, after which time db-cAMP was omitted from the medium. Under these conditions the cells continue to maintain their differentiated morphology for at least 4 days thereafter. These morphological studies demonstrate that dissociated neonatal cardiac muscle cells are able to grow and differentiate in a chemically defined medium in the absence of animal serum.
Upregulated H-Current in Hyperexcitable CA1 Dendrites after Febrile Seizures

Somatic recordings from CA1 pyramidal cells indicated a persistent upregulation of the h-current (Ih) after experimental febrile seizures. Here, we examined febrile seizure-induced long-term changes in Ih and neuronal excitability in CA1 dendrites. Cell-attached recordings showed that dendritic Ih was significantly upregulated, with a depolarized half-activation potential and increased maximal current. Although enhanced Ih is typically thought to be associated with decreased dendritic excitability, whole-cell dendritic recordings revealed a robust increase in action potential firing after febrile seizures. We turned to computational simulations to understand how the experimentally observed changes in Ih influence dendritic excitability. Unexpectedly, the simulations, performed in three previously published CA1 pyramidal cell models, showed that the experimentally observed increases in Ih resulted in a general enhancement of dendritic excitability, primarily due to the increased Ih-induced depolarization of the resting membrane potential overcoming the excitability-depressing effects of decreased dendritic input resistance. Taken together, these experimental and modeling results reveal that, contrary to the exclusively anti-convulsive role often attributed to increased Ih in epilepsy, the enhanced Ih can co-exist with, and possibly even contribute to, persistent dendritic hyperexcitability following febrile seizures in the developing hippocampus.
Modeling feature perception in brief displays with evidence for positive interdependencies

Recent studies have begun to test certain fundamental assumptions underlying popular models of feature perception. This research is continued here. It was discovered that every basic assumption that was open to test in the present study was disconfirmed. However, several new characteristics of line and curve feature perception were discovered: (1) Feature perception sensitivity was inversely related to the number of features present in a stimulus pattern, and the decision criteria for reporting a feature decreased with the number of features contained in a pattern; (2) the decrements in sensitivity reported in (1) were greater for features lying inside a pattern than for those on the exterior; and (3) feature perception sensitivity actually improved if another feature was known to be correctly perceived during the same trial. Likewise, feature sensitivity decreased if another feature was missed on any trial. At the present time, a system that first extracts global and then local (more detailed) featural information provides a basis that qualitatively accounts for our findings and is also compatible with several other studies in the literature.
Photosynthetic consequences of Marssonina leaf spot differ between two poplar hybrids

Summary • In foliage of two hybrid poplars, clone DN-34 ( Populus deltoides × P. nigra ) and clone NM-6 ( P. nigra × P. maximowiczii ), we examined relationships between photosynthesis and severity of leaf spot induced by Marssonina brunnea f. sp. brunnea , a common disease of many tree species in the Populus genus with the potential to affect growth. • Gas exchange was measured on asymptomatic and diseased foliage in monoculture stands of each clone. The equation Y = (1 ‐ x ) β was used to characterize the relationship between relative photosynthesis ( Y ) and percent leaf spot ( x ), where β represents the ratio between functional impairment and measured lesion area. • Leaf photosynthesis was strongly and negatively correlated with leaf spot severity in both hybrids, and β -values indicated that photosynthetic impairment extended beyond visibly damaged leaf tissue. However, large differences in β between hybrids indicated differential photosynthetic consequences for a given leaf spot severity. For each hybrid, values of β were positively related to photosynthetic photon flux density incident upon the leaf during gas exchange measurement. • Declines in leaf photosynthesis appeared to result from a disruption of the photosynthetic apparatus by the invading pathogen. However, specific causes for the differential photosynthetic responses of the two hybrids to disease remained elusive.
Performance of a Three-Phase, Spray-Column, Direct-Contact Heat Exchanger

A numerical model of a three-phase, direct-contact, spray-column heat exchanger has been developed. This model has been used to calculate performance information about this type of device and to compare, where possible, to experiments. General equations are defined for distance up the column using a physically based model for the local heat transfer. This model has been used to investigate a number of characteristics of these devices, such as temperature and holdup distributions through the column. A new formulation is given for a mixed, time-averaged temperature that may be representative of measurements taken with temperature transducers in direct-contact heat exchangers. Little has been given in the literature about quantitative variations of performance as a function of the key independent variables, and information on these aspects is presented here. Although the results presented are for a specific geometry (0.61 m diameter, 3 m active column height, evaporating pentane in 85/sup 0/ C water), the variations shown can give insights generally into the factors affecting performance in these devices. In virtually all cases examined here, extremely good comparisons are shown between predictions and measurements. Conclusions are drawn about the applicability of the model and the important effects demonstrated.
Interfacial characterization of a SiC fiber-reinforced AlN composite

In this study, an attempt was made to improve the mechanical properties of AlN by the incorporation of SiC (SCS-6) fibers (TEXTRON Specialty Materials, Lowell, MA) in a unidirectional array. The SiC fibers are one of the most important reinforcements for ceramic- and metal-matrix composites due to high tensile strength (3,450 MPs), high tensile modulus (400 GPa), and low density (3.0 g/cc). The SiC fiber (15 vol %)-reinforced AlN composite was fabricated by hot-pressing in vacuum. The microstructure and chemistry of interfacial regions in as-fabricated and crept composite were characterized using analytical transmission electron microscopy, in order to investigate the nature of the reaction between the fiber and matrix during both composite fabrication and creep tests and to understand the reinforcing effects of SiC fiber in the AlN matrix. Interfacial characteristics of the composite play an important role in influencing the mechanical properties of the composite.
env Genes of avian retroviruses: Nucleotide sequence and molecular recombinants define host range determinants

Abstract The env gene of avian sarcoma and leukosis retroviruses is allelic in the virus population permitting the virus to use different host cell receptors. This polymorphism has allowed the classification of these viruses into different subgroups. In order to understand further the role of viral sequences involved in determining this host range phenomenon, we constructed molecular recombinants between subgroup A, B, and E viruses and showed that the host range determinant defining subgroup specificity was located within a 1.1-kb region of the genome that included most of the coding region for the env gene product gp85. We also determined the nucleotide sequence of the region of the env gene encoding gp85 for virus isolates representing subgroup A and B viruses. We compared the predicted amino acid sequences of gp85 to themselves and to the previously published sequences of subgroup B, C, and E env genes. Based on these comparisons, we draw the following conclusions: (i) Within the gp85 coding domain, there are four variable regions (VR-1 to VRA) ranging in size from 9 to 52 amino acids. (ii) The variable regions are located in the same relative positons for each of the env gene alleles compared. (iii) The variable regions range in homology from 42% (A compared to B) to 57% (C compared to E) in pairwise comparisons; the flanking conserved domains are on average 959 homologous. (iv) The sequences of three different subgroup B virus isolates are highly homologous in both the conserved and variable regions. Secondary structure predictions suggest that gp85 is composed mostly of β sheet topology. Hydrophilic loops within the variable regions may define sites of receptor interaction and binding sites for subgroup specific neutralizing antibodies.
Neuroscience: Reward alters specific connections

How does the brain couple a fleeting sensory input to a delayed reward during learning? A study in locusts shows that coincident firing of neurons can 'mark' a neuronal connection for later modulation. See Article p.47 Associative learning is thought to involve synaptic plasticity and neuromodulation, but how neuronal circuits determine which synapses should change when blanketed with a nonspecific reinforcer signal has remained mysterious. Focusing on the locust olfactory system, Stijn Cassenaer and Gilles Laurent now demonstrate that 'spike-timing-dependent plasticity' acts as a synaptic tag, which exclusively labels the synapses that act in response to specific odorants. This primes them for subsequent modification by octopamine, a neuromodulator involved in insect learning and memory. The findings explain how neuromodulators can produce specific circuit effects even though their release is both diffuse and delayed relative to sensory inputs.
Quadratic detection of signals with drifting phase

The problem of detecting a sinusoid with drifting phase in the presence of additive white Gaussian noise is considered. A Lorentzian signal model is used, in which the signal to be detected is modeled as a sinusoid whose phase is drifting with Brownian motion. A class of quadratic detectors that trade off coherent and noncoherent averaging of the received waveform is studied. The deflection ratio is used as a performance criterion, and the optimum quadratic detector structure as parametrized by the phase bandwidth is derived. Then, the performance relative to the optimum of a class of suboptical detectors called m‐order noncoherent detectors is considered. It is shown that the best detector in this class performs nearly as well as the optimum quadratic detector. This is in sharp contrast with standard envelope detection whose performance is shown to degrade severely in the presence of phase drift. Simulated detection probabilities that verify this performance disparity are also presented.
Fire retardancy and morphology of nylon 6-clay nanocomposite compositions

We investigated the effect of organically modified clay on the thermal and flammability behavior of nylon 6 nanocomposites. We also used zinc borate along with layered silicate with an aim of achieving synergistic effect in flame retardancy. It is found that addition of 10 wt% clay reduced the onset decomposition (5% wt loss) temperature of nylon 6 by 20°C, while addition of 5 wt% zinc borate and 5 wt% clay in combination reduced it by around 10°C. Differential thermogravimetric analysis indicated that the peak decomposition temperature was not affected by the addition of clay, but the rate of weight loss decreased with increasing clay concentration. The horizontal burning behavior of the nanocomposite films of approximately 0.5mm thickness changed with additive concentration. The nanocomposites with 2.5 wt% and 5 wt% clay burned for almost the same duration as neat nylon 6 but dripping was reduced. The 10 wt% clay nanocomposite sample burned without any dripping and the flame spread rate was reduced by 25-30%. The burn rate of 5 wt % zinc borate/5 wt% clay nanocomposite sample was about 20% higher than that of 10 wt% clay nanocomposite sample, which could be attributed to varying char morphology. Scanning electron microscopy images of the 10wt% clay nanocomposite char surface and cross- section revealed an integrated layer of clay platelets with increasing density gradient from the center to the surface, while the 5 wt% zinc borate/5 wt% clay nanocomposite char appeared foamy and porous. The 5 wt% zinc borate and 5 wt% clay sample developed into a very good intumescent system in cone calorimeter test, swelling about 10-13mm height prior to ignition forming a cellular char structure. This was as effective as the 10wt% clay nanocomposite sample in reducing the heat release and mass loss rate of nylon 6 by around 65%. Fourier transform infrared spectroscopy of the 10 wt% clay nanocomposite char showed the presence of amides, indicating possible residual polymer within the shielded char.
Possibility of lasers based on the innershell transitions of Ne-like and Ni-like ions

Our earlier papers showed that laser gain is possible on the innershell 2s-2p transitions of Ne-like ions. This result was confirmed by more comprehensive calculations. In more recent works it was shown that laser gain is also possible on transitions between highly excited states. We summarize these results and present atomic-kinetic calculations for gain values along the Ne-like sequence for argon, iron, krypton, silver and xenon. For these ions the optimum plasma conditions are found for all possible laser transitions. We have also found some unknown laser transition in Ni-like tantalum and the optimum plasma parameters for laser action on these transitions.
IRAK4 Dimerization and trans-Autophosphorylation Are Induced by Myddosome Assembly

Trans-autophosphorylation is among the most prevalent means of protein kinase activation, yet its molecular basis is poorly defined. In Toll-like receptor and interleukin-1 receptor signaling pathways, the kinase IRAK4 is recruited to the membrane-proximal adaptor MyD88 through death domain (DD) interactions, forming the oligomeric Myddosome and mediating NF-κB activation. Here we show that unphosphorylated IRAK4 dimerizes in solution with a KD of 2.5 μM and that Myddosome assembly greatly enhances IRAK4 kinase domain (KD) autophosphorylation at sub-KD concentrations. The crystal structure of the unphosphorylated IRAK4(KD) dimer captures a conformation that appears to represent the actual trans-autophosphorylation reaction, with the activation loop phosphosite of one IRAK4 monomer precisely positioned for phosphotransfer by its partner. We show that dimerization is crucial for IRAK4 autophosphorylation in vitro and ligand-dependent signaling in cells. These studies identify a mechanism for oligomerization-driven allosteric autoactivation of IRAK4 that may be general to other kinases activated by autophosphorylation.
A comment on jovian greenhouse models

Abstract Radiative greenhouse models of Jupiter's atmosphere seriously overestimate the temperature of the lower cloud level because they neglect the convective transport of heat.
Conformational Dynamics of Ras Isoforms: Specificity at the Catalytic Domain

Ras proteins serve as crucial signaling modulators in cell proliferation through their ability to hydrolyze GTP and cycle between GTP “On” and GTP “off” states. There are four different human Ras homologues and the sequence homology is almost conserved at the catalytic domain. These homologues differ in their ability to activate different effectors and hence different signaling pathways. Much of the previous work on Isoform specificity has attributed this difference to the HVR region of Ras proteins which dictates its localization in the membrane. In this work, we have analyzed the specific dynamics in the catalytic domain of two Ras Homologues H-ras and K-ras to probe for alterations in the active site architecture that could possibly provide effector and modulator specificity to the different isoforms. We explored the conformational dynamics between of WT H-ras and K-Ras proteins and compared the conserved communications and residue interactions between these two proteins at the catalytic domain. We have also studied the dynamics of a transforming mutant of H-ras and K-ras and an effector selective??? mutant of H-ras. Preliminarily analysis revealed that there is a distinct conformational distribution for K-ras and H-ras, including in the functionally important switch regions. Collectively we have determined that wild type K-ras is more dynamic than H-ras and that the structure of the effector binding loop more closely resembles that of the T35S Raf-selective mutant, providing new insight into the mode of effector specificity at the catalytic domain. Furthermore we have determined that specific mutations in H-ras and K-ras perturb the conformational equilibrium differently.
The question of gauge dependence of transition probabilities in quantum mechanics: Facts, myths and misunderstandings

Abstract We show that, in terms of physical observables, transition probabilities in quantum mechanics can be calculated in a truly gauge invariant way, i.e., independent of the choice of gauge and that recent arguments for the preference of a particular gauge are due to misconceptions.