cssi/SciSciGPT-SciSciNet huggingface dataset:
In Vivo Whole-Cell Recording of Odor-Evoked Synaptic Transmission in the Rat Olfactory Bulb

One of the first steps in the coding of olfactory information is the transformation of synaptic input to action potential firing in mitral and tufted (M/T) cells of the mammalian olfactory bulb. However, little is known regarding the synaptic mechanisms underlying this process in vivo. In this study, we examined odor-evoked response patterns of M/T and granule cells using whole-cell recording in anesthetized, freely breathing rats. We find that odor-evoked excitatory responses in M/T cells typically consist of bursts of action potentials coupled to the approximately 2 Hz respiration rhythm. Odor-evoked, rhythmic M/T cell excitation is reliable during odor presentation (2-4 sec); in contrast, both excitatory responses of granule cells and M/T cell lateral inhibition adapt quickly after the first respiration cycle in the presence of odorants. We also find that the amplitude and initial slope of odor-evoked synaptic excitation play an important role in regulating the timing of M/T cell spikes. Furthermore, differences in odor concentration alter the shape of odor-evoked excitatory synaptic responses, the latency of M/T cell spikes, and the timing of M/T cell lateral inhibition.
Foundations of Simulation Modeling

Simulation modeling is an important step of a simulation study. It concerns with the creation of an efficient simulation model as accurate as needed to mimic the behavior of the underlying system and to reproduce useful observations for subsequent analysis. This introductory article discusses three main simulation modeling methods: discrete-event simulation, continuous simulation, and agent-based simulation. In particular, three discrete-event simulation modeling paradigms are introduced: event scheduling, process interaction, and activity scanning. Several modeling issues are exemplified by a simple single-server queueing system and a slightly more complex multiple-server finite capacity queueing system with impatient customers. Continuous simulation is briefly discussed to draw the differences between discrete-event and continuous simulations. Simulating emergent behavior as a common purpose of agent-based simulation is demonstrated by a classic game of life model and a variation model. Monte-Carlo simulation and other simulation modeling formalisms are briefly highlighted. Keywords: simulation models; event scheduling; process interaction; agent-based models
Prospects for microtechnology and nanotechnology in bioengineering of replacement microvessels.

Abstract Context.—Due to its anticipated curative potential, therapeutic angiogenesis recently became a major preoccupation for the biomedical research community. Most of the related work reported to date employs either biochemical or genetic tools. Objective.—To identify opportunities for application of the current developments in microtechnology and nanotechnology to the field of therapeutic angiogenesis. Data Sources.—Survey of recent English-language literature on microvascular tissue engineering in the context of therapeutic angiogenesis. We include our results regarding the role played by microtopographical cues in the progression of angiogenesis, such as those produced during processing of the extracellular matrix by chronic inflammatory cells. Conclusion.—While notable accomplishments have been identified in the field of tissue engineering of larger vessels, reports on purposeful assembly of microvascular structures with the ability to be transferred in vivo by implantation are still scarce. Under...
Objective Detection of Center of Tropical Cyclone in Remotely Sensed Infrared Images

In the present work, an objective technique has been presented to fix the center position of TC in the satellite generated infrared images. The basis of the technique is to determine the point around which the fluxes of the gradient vectors of brightness temperature (BT) are converging. First, variance of brightness temperature at each pixel from its neighboring pixels is computed and then flux of the gradient of variance values is computed. Next, a line parallel to the gradient vector at each pixel is drawn across the image, and the locations where these lines intersect each other are stored in a density matrix. The score values accumulated in the density matrix are averaged and location with the highest score is identified. This position is considered to be the center location of the cyclone. The technique has been tested over the Kalpana satellite generated (approximately 1000) IR images of the cyclones that formed during the period 2009-2010. The technique has been used in fully automated mode for the four cyclones viz., Phyan, Ward, Laila, and Phet. The half hourly sequential IR images during the life period of each cyclone is analyzed and the center position is determined. The track of cyclone obtained by the automatically determined center position is compared with the observed track obtained from Joint Typhoon Warning Centre (JTWC). The mean track error with respect to JTWC observations for four cyclones Phyan, Ward, Laila, and Phet was computed and found as 42, 82, 58, and 42.5 km, respectively.
Statistical significance of modal parameters of bridge systems identified from strong motion data

SUMMARY Modal parameters of structural systems have commonly been determined using system identication (SI) methods for damage detection and health monitoring. For determining the deterioration of the integrity of structural systems correctly, modal parameters of a healthy structure have to be obtained with adequate certainty so that these parameters can be used as reliable references for the healthy system to compare with those of the damaged system. In this study, the statistical signicance of modal parameters identied using strong motion time histories recorded on two bridge structures is assessed. The condence intervals of identied modal frequencies and damping ratios are obtained using Monte Carlo simulations and sensitivity analyses in conjunction with eigenrealization algorithm. The dependence of the statistical bounds on model parameters is examined. The eect of using dierent number of sensors on the statistical signicance is evaluated using simulated time history data from a validatednite element model of a bridge. Copyright ? 2005 John Wiley & Sons, Ltd.
Interactions of mitochondria with the actin cytoskeleton.

Abstract Interactions between mitochondria and the cytoskeleton are essential for normal mitochondrial morphology, motility and distribution. While microtubules and their motors have been established as important factors for mitochondrial transport, emerging evidence indicates that mitochondria interact with the actin cytoskeleton in many cell types. In certain fungi, such as the budding yeast and Aspergillus, or in plant cells mitochondrial motility is largely actin-based. Even in systems such as neurons, where microtubules are the primary means of long-distance mitochondrial transport, the actin cytoskeleton is required for short-distance mitochondrial movements and for immobilization of the organelle at the cell cortex. The actin cytoskeleton is also involved in the immobilization of mitochondria at the cortex in cultured tobacco cells and in budding yeast. While the exact nature of these immobilizations is not known, they may be important for retaining mitochondria at sites of high ATP utilization or at other cellular locations where they are needed. Recent findings also indicate that mutations in actin or actin-binding proteins can influence mitochondrial pathways leading to cell death. Thus, mitochondria–actin interactions contribute to apoptosis.
Family instability during early and middle adolescence

Abstract Two studies investigated associations between family instability (changes in parents' intimate partners, work hours, residence, children's schools) and adolescent adjustment. In Study 1 (N = 141, M age = 15.23 years), instability was associated with increased caregiver-reported externalizing and internalizing behaviors (including youth-reported cigarette use), reduced teacher-reported frustration tolerance, social skills, task orientation, and lower academic grades. Logistic regression results for instability exposure showed an increased risk for school suspensions, Person in Need of Supervision status, binge drinking, and marijuana use. In Study 2 (N = 225, M age = 13.37 years), instability was linked to adolescent-reported externalizing and internalizing behaviors, teacher-reported disruptions, and lower English and math grades. Key sociodemographic factors and negative life events were statistically controlled in regression analyses. Results indicate that a more theoretically coherent measure of family instability, which is distinct from negative life events, may prove valuable in understanding the potentially adverse influence of instability on youth.
Increased cAMP in monocytes augments Notch signaling mechanisms by elevating RBP-J and Transducin-like Enhancer of Split (TLE)

In cells of the innate immune system, pathological increases in intracellular cAMP attenuate immune responses and contribute to infections by bacteria such as Bacillus anthracis. In this work, cAMP from B. anthracis edema toxin (ET) is found to activate the Notch signaling pathway in both mouse macrophages and human monocytes. ET as well as a cell-permeable activator of PKA induce Notch target genes (HES1, HEY1, IL2RA, and IL7R) and are able to significantly enhance the induction of these Notch target genes by a Toll-like receptor ligand. Elevated cAMP also resulted in increased levels of Groucho/transducin-like enhancer of Split (TLE) and led to increased amounts of a transcriptional repressor complex consisting of TLE and the Notch target Hes1. To address the mechanism used by ET to activate Notch signaling, components of Notch signaling were examined, and results revealed that ET increased levels of recombinant recognition sequence binding protein at the Jκ site (RBP-J), a DNA binding protein and principal transcriptional regulator of Notch signaling. Overexpression studies indicated that RBP-J was sufficient to activate Notch signaling and potentiate LPS-induced Notch signaling. Further examination of the mechanism used by ET to activate Notch signaling revealed that C/EBP β, a transcription factor activated by cAMP, helped activate Notch signaling and up-regulated RBP-J. These studies demonstrate that cAMP activates Notch signaling and increases the expression of TLE, which could be an important mechanism utilized by cAMP to suppress immune responses.
Thermally stable lithium salts for polymer electrolytes

Abstract Chemical and electrochemical characterization of two new Li salts which exhibit high conductivity in both liquid and polymer solvent systems are presented. When dissolved in non-aqueous solvents such as tetrahydrofuran LiN(SO2CF3)2, Li bis-(trifluoromethanesulfonyl)imide and LiC(SO2CF3)3, Li tris-(trifluoromethanesulfonyl)methide are the two most highly conductive organic anion-based Li salts known. Cyclic voltammetry studies show both salts to be electrochemically stable beyond 4 V vs Li. They are also stable indefinitely at elevated temperatures, eg 100°C, unlike the large class of inorganic Li salts based on perhalogenated transition metal and main group ions.
An Embedding Method for the Cauchy—Riemann Equations

On propose une methode de plongement des equations de Cauchy-Riemann dans un systeme d'equations du second ordre. On recherche alors la solution des equations de depart en imposant un systeme plonge des conditions aux limites appropriees. On developpe une approche par les moindres carres
Epiflow-A paradigm for tracking stereo correspondences

We propose the epiflow as a novel framework to integrate the motion and stereo epipolar geometries for the tracking of stereo matches. For a given stereo pair, spatio-temporal correspondences in the next stereo pair are established from the solution of an optimization problem that incorporates the epiflow geometrical constraint with the brightness constancy assumption as the photometric similarity measure. Two different implementations are proposed, each utilizing the stereo RANSAC algorithm as a mechanism to gain robustness and efficiency in handling large temporal disparity ranges, identify outliers and estimate the motion of the stereo rig as complementary information. The performance of the proposed methods is demonstrated in experiments with various complex underwater images, and comparison with results from the SIFT method allows the assessment of our novel contributions.
Redox and spectral properties of flavodoxin from Anabaena 7120

We report here on the spectrophotometric and electrochemical properties of the flavodoxin from Anabaena 7120 and compare these properties with those of flavodoxins that have been studied previously. Molar absorption coefficients have been determined for all three oxidation states of this protein, at various wavelengths. For oxidized flavodoxin, molar absorption coefficients for the absorption maxima at 464 and 373 nm were 9200 and 8500 M-1 cm-1, respectively. Reduction by the first electron produced a neutral blue semiquinone which exhibited an absorption maximum at 575 nm. The molar absorption coefficients at 575 nm were 200 M-1 cm-1 for the oxidized form, 5100 M-1 cm-1 for the semiquinone form, and 250 M-1 cm-1 for the hydroquinone form. Redox potentials have been determined, in the pH range of 6.0 to 8.5, for both electron transfers. At pH 7.0, the midpoint potential values for the first and second electron transfers were -0.196 and -0.425 V, respectively. We determined that the first electron transfer is pH dependent and that a proton transfer accompanies this one electron transfer. It was also determined that the second electron transfer is pH independent in the pH range of 6.0 to 8.5.
A controlled scratch test for measuring the elastic property, yield stress and contact stress–strain relationship of a surface

Abstract The procedure for a controlled scratch test to measure the elastic property, yield stress and contact stress–strain relationship of a surface is described. A hard sphere scratches the surface at a progressively increasing load. The contact deformation is firstly elastic and then elastic–plastic. The contact width between the sphere and the surface as a function of normal load is measured and the relationship between the contact pressure and scratch strain is obtained. The elastic property and yield stress of the surface are then derived from the curve with good accuracy. The strain hardening ability of the surface can also be estimated from the curve. This method is very valuable for thick coatings and brittle materials in which these mechanical properties are difficult to obtain by other methods.
Human immunodeficiency virus and the peripheral nervous system workshop

To provide a venue for a comprehensive multidisciplinary review of the current state of knowledge regarding the human immunodeficiency virus–associated peripheral neuropathies and to provide the institute with guidance in formulating future research initiatives, the National Institute of Neurological Disorders and Stroke (Bethesda, Md) convened a workshop on September 18 through 19, 2000. The participants were chosen from various disciplines and included clinicians, pathologists, neurobiologists, neurophysiologists, virologists, and neuroimmunologists. The present article summarizes the highlights of the meeting and includes the recommendations developed by the participants for future research. As might be expected in a rapidly evolving scientific field, the meeting was characterized by a lively and far-ranging discussion of data interpretation, experimental approaches, and priorities for future research. However, the recommendations presented at the end of this article constitute a consensus judgment reached by all of the participants of the most important areas for future research.
Evaluation of Surface Plasmon Resonance Biosensors for Detection of Tetrodotoxin in Food Matrices and Comparison to Analytical Methods

Tetrodotoxin (TTX) is a low molecular weight neurotoxin found in a number of animal species, including pufferfish. One emerging method for TTX detection employs surface plasmon resonance (SPR) immunosensors. SPR, an optical technique that allows for label-free, real-time, multiplexed analysis, can have detection limits that rival many of the conventional transduction methods. Preliminary SPR approaches for TTX were successful, yet suffered from low throughput and used noncommercial instrumentation. To advance this method for broader use, the immunoassay was transferred to a commercial instrument and optimized for improved detection. This manuscript outlines the assay development and results for complex matrices relevant to seafood safety (pufferfish) and food adulteration (milk, apple juice). In addition, results are compared to those obtained using receptor binding assay, ELISA, HPLC-FD, and LC/MS/MS detection techniques. Results highlight the advantages of SPR assays, including rapid screening capability with low reagent consumption and low- to subppb detection limits.
A Bayesian Mixture Model for Partitioning Gene Expression Data

In recent years there has been great interest in making inference for gene expression data collected over time. In this article, we describe a Bayesian hierarchical mixture model for partitioning such data. While conventional approaches cluster the observed data, we assume a nonparametric, random walk model, and partition on the basis of the parameters of this model. The model is flexible and can be tuned to the specific context, respects the order of observations within each curve, acknowledges measurement error, and allows prior knowledge on parameters to be incorporated. The number of partitions may also be treated as unknown, and inferred from the data, in which case computation is carried out via a birth-death Markov chain Monte Carlo algorithm. We first examine the behavior of the model on simulated data, along with a comparison with more conventional approaches, and then analyze meiotic expression data collected over time on fission yeast genes.
Reproductive Characteristics of the Mexican Woodrat at the Northern Limit of Its Range in Colorado

The reproductive biology of the Mexican woodrat (Neotoma mexicana) was studied for 16 months along the Front Range of northern Colorado from February 1966 through May 1967. Adult females bred from March through May and produced two litters annually. The mean litter size for adult females was 3.43 ± 0.35 based on embryo counts, 3.66 ± 0.31 based on corpora lutea, and 3.47 ± 0.39 based on placental scars. Juvenile females born in April and May developed rapidly and produced litters in June or July while still partially or wholly in the gray, juvenile pelage. Young females had an average of 2.44 ± 0.27 embryos and 2.52 ± 0.31 corpora lutea. Some young females born late in the reproductive season, ovulated in September and October, but failed to produce litters. Reproductive failure was apparently due to an absence of fertile males in the population at that time. Peak testicular development occurred in April, 1966 and 1967 (mean weight, 1470.6 ± 257.2 and 1540.2 ± 288.4 milligrams, respectively), and minimal testicular size and activity occurred in November, 1966 (mean weight, 119.6 ± 21.7 milligrams). The gonadal development of juvenile males progressed slowly in 1966 compared to juvenile females. Mean testicular weight and activity remained low through November (mean weight, 61.9 ± 12.5 milligrams), then accelerated rapidly in December (mean weight, 476.8 ±81.3 milligrams), and finally reached full reproductive development during the 1967 breeding season.
Feasibility of intraoperative administration of chemotherapy for gynecologic malignancies: assessment of acute postoperative morbidity.

Abstract In order to assess the acute effects of the intraoperative administration of intraperitoneal (IP) carboplatin with and without intravenous (IV) doxorubicin in patients with gynecologic malignancies, 25 patients were treated at the conclusion of their surgical procedure. Twenty-three had epithelial ovarian cancer and 2 had advanced endometrial cancer. Twelve patients received IP carboplatin and IV doxorubicin at the conclusion of their primary cytoreduction. The remaining 13 received IP carboplatin alone and consisted of 4 reassessment laparotomies for ovarian cancer, 7 secondary cytoreductions, 1 minilaparotomy for the placement of an IP catheter, and 1 second-look laparoscopy. The median age of the 25 patients was 59 years. Eight patients underwent bowel resections with anastamoses; 2 had ureteral resections and ureteroneocystostomies, 1 required a splenectomy, and 1 underwent a partial hepatic resection. There were no mortalities. Three of the 13 patients who received the IP carboplatin alone had postoperative fevers with no infectious source, which did not delay discharge. No other morbidity was noted in this group. However, 7 patients who received IV doxorubicin along with the IP carboplatin developed severe leukopenia requiring antimicrobial and colony-stimulating factor support. One patient required reexploration for postoperative hemorrhage and also developed a pulmonary embolus. One woman developed postoperative pneumonia. The median hospital stay for the 25 patients was 9 days. Intraoperative chemotherapy can be administered with tolerable immediate adverse effects.
Quantization of electrodynamics in nonlinear dielectric media

We point out some problems with the usual quantum-mechanical theory of electrodynamics in nonlinear dielectric media which is used in nonlinear optics. In order to understand these problems, the Hamiltonian formulation of the theory is examined. It is found that many of the difficulties in the usual theory are a result of the fact that the canonical momentum for the interacting theory is not the same as that for the free electromagnetic field theory.
Bayesian Semiparametric Median Regression Modeling

Median regression models become an attractive alternative to mean regression models when employing flexible families of distributions for the errors. Classical approaches are typically algorithmic with desirable properties emerging asymptotically. However, nonparametric error models may be most attractive in the case of smaller sample sizes where parametric specifications are difficult to justify. Hence, a Bayesian approach, enabling exact inference given the observed data, may be appealing. In this context there is little Bayesian work. We develop two fully Bayesian modeling approaches, employing mixture models, for the errors in a median regression model. The associated families of error distributions allow for increased variability, skewness, and flexible tail behavior. The first family is semiparametric with extra variability captured nonparametrically through mixing and skewness handled parametrically. The second family, a fully nonparametric one, includes all unimodal densities on the real line with...
Optical Response of AgCl and AgBr in the Near and Extreme Ultraviolet

The extinction coefficients of AgCl and AgBr have been obtained down to liquid-helium temperature by observing the transmission of thin films in the near-uv direct exciton region (3.5-6.7 eV) and in the extreme uv (30-240 eV) using synchrotron radiation. The index of refraction was determined for both materials by a dispersion relation, and the optical constants were then constructed for AgCl in the range 3-240 eV, using all available data. Some interpretation of the exciton and band-to-band spectra is given. An estimate is made of the effective number of electrons which contribute to the absorption over a wide range of photon energies.
Measurement and interpretation of growth responses of Pinus resinosa Ait. to K-fertilization.

Abstract The growth response of Pinus resinosa Ait. to K-fertilization over a 21-year period is evaluated using radial growth and cross-sectional area at three positions on the stem, and height, volume, biomass and specific volume. Data shows that the different measures of growth give different results for the longevity and magnitude of fertilizer response. It is concluded that the most appropriate measure of the direct effect of fertilization is specific volume, while volume and biomass best measure the direct-residual effects of fertilization.
Aminoaciduria and proteinuria in rats after a single intraperitoneal injection of Ni(II).

Proteinuria was found in Fischer female rats after a single ip injection of NiCl/sub 2/ in dosages from 34 to 85 ..mu..mol/kg (2 to 5 mg Ni/kg). Generalized ..cap alpha..-aminoaciduria was found after a single ip injection of NiCl/sub 2/ in dosages of 68 to 85 ..mu..mol/kg (4 and 5 mg Ni/kg). Amino acids in plasma were normal or slightly diminished from 1 to 48 hr after injection of Ni(II). Electron microscopy of kidneys of five rats at 48 hr after Ni(II) (68 ..mu..mol/kg) consistently revealed fusion of foot processes of glomerular epithelial cells. Focal tubular necrosis was present in the kidney of one of these rats. This study demonstrates that toxic nephropathy with aminoaciduria and proteinuria develops in rats after ip Ni(II). Amino acid and protein excretions consistently returned to normal by Day 5.
A Reduced Role of V/Q Scintigraphy in the Diagnosis of Acute Pulmonary Embolism

Ventilation/perfusion (V/Q) lung scintigraphy, when used for the clinical determination of the presence or absence of pulmonary embolism, has been much studied by medical imagers. Inherent to a “cold-spot” scan targeting the normal pulmonary tissue, the deck has always been stacked against us
Conductive Polymer / Superconductor Sandwich Structures

Methods for characterizing the interface of conductive polymer/high-Tc superconductor sandwich structures are reported. Electrochemical procedures, such as cyclic voltammetry and chronoamperometry, are utilized to deposit conductive polymers directly onto bulk ceramic and thin film samples of YBa2Cu3O7-δ. Moreover, similar methods are utilized to cycle the polymer structures between their neutral (non-conductive) and oxidized (conductive) forms. Through changes in the polymer doping level, the superconducting properties of the high-Tc component can be modulated in a controllable and reproducible fashion. This paper focuses on an analysis of conductive polymer/superconductor interface phenomena as explored by electrochemical, resistivity vs. temperature and contact resistance measurements.
Alumina-promoted Opening of Medium Ring Epoxides: cis-Cyclooctene Oxide - trans-2-Acetoxycyclooctanol

Abstract Opening of epoxides is usually achieved homogeneously by treating oxiranes with strong acids or strong bases; several reviews of this subject are available.2 We have discovered that commercially available chromatographic -alumina promotes highly efficient heterogeneous opening of a wide range of epoxides by a variety of nucleophiles (e.g., alcohols, acetic acid, amines, mercaptans, and selenols) under extraordinarily mild (25[ddot]) and neutral conditions and that this procedure is the method of choice for clean nucleophilic opening of medium ring epoxides.3
Oral administration of chronic physostigmine does not improve cognitive or mnesic performances in Alzheimer's presenile dementia.

Physostigmine was administered orally 1 mg q.i.d. for one month to 8 patients with a clinical diagnosis of Alzheimer's presenile dementia. The possible beneficial effects of the drug were evaluated by means of a neuropsychological battery administered to all patients before and after treatment. The performances obtained by demented patients on retest did not show any difference in comparison with performances obtained on the first neuropsychologic assessment. Some implications of these negative results are briefly discussed.
Spaces for experience [multimedia presentation]

Don't use interactive technology to do what can be more gracefully done elsewhere. Use the elaborate functions of multimedia only to do what cannot otherwise be done. Don't, for example, have users read large chunks of material on the computer, when they can digest this material much more efficiently and pleasantly in a book. Mix traditional presentations with the kind of questioning and investigative formats provided by interactivity. Like TV, this medium is designed for a short attention span. Try to find the most economical and dramatic way of presenting an idea or fact. This technology invites us to embrace the process, to enjoy the journey as much as the goal. Because it asks users to interject their own choices and opinions, it can challenge authority and help deconstruct received, standard forms of knowledge. So, play with new formats and unusual combinations of elements. The more daring your imagination, the more exciting and stimulating. >
Splintering School Districts: Understanding the Link between Segregation and Fragmentation

This article examines the process of fragmentation to understand how the process of establishing new school districts results in high metropolitan-area segregation. Using educational and census data, the article examines how the political process of creating new school districts in Jefferson County, Alabama, changed the nature of segregation. School segregation remained high from 1960 to 2005, but while in the late 1960s segregation of students was predominantly within districts, by 2005 segregation was primarily between districts. Over time, school district boundary lines gained meaning in terms of the characteristics of the district residents. In creating separate districts, local control has the same effect as earlier de jure laws of maintaining racial segregation in the Birmingham area, with few prospects for overcoming boundaries that divide students and opportunities along racial lines. Local control within the current judicial context will define separate populations and maintain or increase metropolitan segregation.
Interactions between modulators of the GABAA receptor: Stiripentol and benzodiazepines

Abstract Many patients with refractory epilepsy are treated with polytherapy, and nearly 15% of epilepsy patients receive two or more anti-convulsant agents. The anti-convulsant stiripentol is used as an add-on treatment for the childhood epilepsy syndrome known as severe myoclonic epilepsy in infancy (Dravet syndrome). Stiripentol has multiple mechanisms of action, both enhancing GABAA receptors and reducing activity of metabolic enzymes that break down other drugs. Stiripentol is typically co-administered with other anti-convulsants such as benzodiazepines which also act through GABAA receptor modulation. Stiripentol slows the metabolism of some of these drugs through inhibition of a variety of cytochrome P450 enzymes, but could also influence their effects on GABAergic neurotransmission. Is it rational to co-administer drugs which can act through the same target? To examine the potential interaction between these modulators, we transiently transfected HEK-293T cells to produce α3β3γ2L or α3β3δ recombinant GABAA receptors. Using whole-cell patch clamp recordings, we measured the response to each benzodiazepine alone and in combination with a maximally effective concentration of stiripentol. We compared the responses to four different benzodiazepines: diazepam, clonazepam, clobazam and norclobazam. In all cases we found that these modulators were equally effective in the presence and absence of stiripentol. The δ-containing receptors were insensitive to modulation by the benzodiazepines, which did not affect potentiation by stiripentol. These data suggest that stiripentol and the benzodiazepines act independently at GABAA receptors and that polytherapy could be expected to increase the maximum effect beyond either drug alone, even without consideration of changes in metabolism.
Climate and vegetation in the middle east : Interannual variability and drought feedbacks

Abstract The Euphrates Plain (EP) experiences large interannual variability in vegetation cover, especially in areas of marginal rain-fed agriculture. Vegetation in this region is primarily limited by available soil moisture, as determined by winter precipitation, spring precipitation, and air temperature. Satellite analyses indicate that the springtime normalized difference vegetation index (NDVI) is negatively correlated with surface albedo, and that interannual variability in albedo in the EP produces an estimated forcing on the radiation balance that peaks at 16.0 W m−2 in May. Simulations with a regional climate model indicate that surface energy fluxes during a drought year (1999) differed substantially from those during a year with normal precipitation (2003). These differences were geographically specific, with the EP exhibiting increased albedo and decreased sensible heat flux while the neighboring Zagros Plateau region showed no albedo effect, a large increase in sensible heat flux, and an offse...
Effect of virtual 4d-shell excitations on rare earth spectra

Ab initio energies for electric dipole transitions 4d10(1S0) to 4d94fJ=1 in triply-ionized lanthanum have been calculated by constructing an effective interaction, acting within the configuration 4d94f, that incorporates effects of virtual 4d-shell excitations to all orders of perturbation. Virtual 4d-shell excitations, included within the random phase approximation, and virtual excitations to singly-excited configurations 4d9 epsilon f are found to reduce the ordinary electrostatic interaction by 38% for the 1P1 term of 4d94f, by 6% for the 3D1 term, and by 3% for the 3P1 term. The relevance of this calculation to rare earth spectroscopy generally is discussed, with particular regard to the usual theoretical problem that calculated term energies are much larger than experimental ones. Present results are in good agreement with experiment and greatly improve upon previous theoretical work.
Hydroxylation of peptide-bound proline and lysine before and after chain completion of the polypeptide chains of procollagen☆

Abstract The synthesis of procollagen hydroxyproline and hydroxylysine was examined in matrix-free cells which were isolated from embryonic tendon by controlled enzymic digestion and then incubated in suspension. After the cells were labeled with [14C]proline for 2 min, or about one-third the synthesis time for a Pro-α chain, [14C]hydroxyproline was found in short peptides considerably smaller than the Pro-α chains of procollagen. The results, therefore, confirmed previous reports indicating that the hydroxylation of proline can begin on nascent chains. In similar experiments in which the cells were labeled with [14C]lysine, [14C]hydroxylysine was found in short, newly synthesized peptides, providing the first evidence that the hydroxylation of lysine can also begin on nascent peptides. However, further experiments demonstrated that the synthesis of hydroxyproline and hydroxylysine continues until some time after assembly of the polypeptide chains is completed.
Sensitivity study of printed wiring board plated-through-holes copper barrel voids

Improved printed wiring board (PWB) manufacturing technology has resulted in more advanced methods for component mounting (such as surface mount technology). Evidence has shown that the new generation of PWBs cannot be built using surface mount technology (SMT) alone. Some passive components and connectors can only be mounted by using plated through holes (PTHs) and vias. Up to now PTHs and vias are still the most widely used inter-layer connections in a PWB. The advanced miniaturization technologies has dramatically reduced the size of a PTH to as small as 5mils and the use of multilayer composite construction further increases the level of design complexity. It has been determined that PTH failure results from thermo-mechanical deformation due to mismatch of coefficients of thermal expansion (CTE) in the out-of-plane (Z) direction between board substrate and the PTH copper plating at elevated temperatures. Although many studies have been conducted concerning the general PTH design what has not yet been evaluated in a systematic and comprehensive manner is the PWB failure resulting from copper barrel plating voids. A collaborative research effort between Georgia Tech and Motorola has recently been carried out to investigate the influence of voids on PTH failures. This study first identifies the basic key design parameters (such as void size void shape void location copper plating thickness etc. ) relevant to void characterization. These parameters with selected values were collectively formed a© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
What Can Molecular and Morphological Markers Tell Us About Plant Hybridization

Abstract The study of hybrids and their evolutionary significance is often based on a number of tacit assumptions regarding character expression in hybrids. This article examines morphological, chemical, and molecular character expression in hybrids to determine whether traditionally recognized properties of hybrid plants, such as hybrid intermediacy and character coherence, are actually supported by empirical evidence, and also examines the impact of hybrids on phylogenetic analyses. We show that hybrids are a mosaic of both parental and intermediate morphological characters rather than just intermediate ones, and that a large proportion of first (64%) and later generation hybrids (89%) exhibit extreme or novel characters. Chemical character expression in hybrids is more predictable, with predominantly additive or complementary expression for both first generation hybrids (68%) and hybrid taxa (54%). Likewise, the genetic basis, and thus the expression of molecular characters, is well-worked out and pred...
Information technology capital budgeting using a knapsack problem

In this paper, we describe an information technology capital budgeting (ITCB) problem, show that the ITCB problem can be modeled as a 0–1 knapsack optimization problem, and propose two different simulated annealing (SA) heuristic solution procedures to solve the ITCB problem. Using several simulations, we empirically compare the performance of two SA heuristic procedures with the performance of two well-known ranking methods for capital budgeting. Our results indicate that the information technology (IT) investments selected using the SA heuristics have higher after-tax profits than the IT investments selected using the two ranking methods.
Effect of combined magnetic bias and drive fields on dynamic magnetomechanical properties of Terfenol-D/epoxy 1–3 composites

Abstract The dynamic magnetomechanical properties of Terfenol-D/epoxy 1–3 magnetostrictive composites with approximately 50% Terfenol-D volume fraction have been investigated under different combined magnetic bias ( H Bias =5–140 kA/m) and drive ( H 3 =1–9 kA/m) fields. These properties include elastic moduli ( E 3 H and E 3 B ), dynamic relative permeability ( μ r 33 T ), dynamic strain coefficient ( d 33 ), magnetomechanical coupling coefficient ( k 33 ), and the ratio of the dynamic strain coefficient to the dynamic susceptibility ( d 33 / χ 33 ). The changes in the composite properties with applied fields can be explained in terms of domain wall motion followed by saturation. At a low H 3 of 1 kA/m, the available non-180° domain state created by residual compressive stresses in the composites results in negative- ΔE, d 33 , k 33 , and d 33 / χ 33 maximizing near H Bias =40 kA/m. As H 3 is increased, domain wall motion occurs, decreasing the H Bias required to maximize the properties by reducing stress-induced anisotropy.
The viscometric behavior of native and relaxed closed circular PM2 DNAs at intermediate and high ethidium bromide concentrations

We have measured the specific viscosity of closed circular PM2 DNA in the presence of concentrations of ethidium bromide ranging up to 5 mg/ml. Both native viral PM2 DNA I and enzymatically prepared relaxed, closed circular PM2 DNA I0 exhibit a complex dependence of the specific viscosity upon the extent of supercoiling. As the number of superhelical turns is increased in the positive sense from zero, the viscosity first decreases to a minimum, then passes through a secondary maximum, and eventually again increases as the dye-induced duplex unwinding proceeds. In the case of DNA I, a corresponding behavior is mirrored in the negative sense as dye is removed from the principal viscometric maximum (complete relaxation of the DNA by dye). The shape of the curve relating specific viscosity to extent to supercoiling is similar for superhelical DNAs of either handedness, a result which we interpret to mean that the influence of any regions of special secondary structure (such as denatured loops) upon the viscosity is minimal. At very high dye concentrations the specific viscosity decreases dramatically. This effect might arise either from intermolecular aggregation or from a dye-induced collapse in the DNA secondary structure.
Electron microscopic autoradiographic studies of gliogenesis in rat optic nerve I. Cell proliferation

Electron microscopy and 3H-thymidine autoradiographic techniques were used to study the fine structure of proliferating cells in developing rat optic nerve. Before the closure of the optic canal almost all of the cells incorporating radioactive thymidine are ventricular cells, but after closure (16 days of gestation) the vast majority are differentiating astroblasts or oligodendroblasts. Labeled astroblasts show a range in their degree of differentiation; some cells lack 90 A cytoplasmic filaments while others have glial filaments and abundant cytoplasmic organelles. In contrast to astroblasts, all of the labeled oligodendroblasts are in the early stages of differentiation. The proliferation of oligodendroblasts starts at five days postnatal, approximately a day or two before the onset of myelination.During myelinogenesis a few of the labeled oligodendroblasts show presumptive connections to myelin sheaths. Microglial cells do not appear to play a major role in gliogenesis since they form less than 2% of all the labeled cells. The results of this study indicate that astroblasts and oligodendroblasts, rather than undifferentiated glioblasts, are the major source of macroglia. The finding that proliferating glia are in the processof differentiation agrees with recent studies which show that differentiated cells can divide.
Critical exponents for the conductivity of random resistor lattices

This paper presents three results concerning the critical exponents which characterize the conduction threshold of a resistor lattice. (a) There are no rigorous inequalities similar to those for the phase-transition critical exponents. (b) There is a dual transformation in two dimensions which relates the critical exponents: in particular $s=t$, $u=\frac{1}{2}$ for the two-dimensional bond problem. (c) The exponents for the two- and three-dimensional bond and site problems are estimated by numerically solving for the voltage distributions of large finite disordered lattices. The results are in agreement with the "scaling" exponent relationship.
The Ionization Cross Section of the Silver L III State

The ionization cross section of the silver ${L}_{\mathrm{III}}$ state has been measured, in arbitrary units, by observing the intensity of the $L\ensuremath{\alpha}$ doublet radiation from a thin target of silver bombarded by cathode rays whose energies ranged up to nine times the excitation energy of the ${L}_{\mathrm{III}}$ state. The observed data are corrected for the effects of diffusion, rediffusion, and retardation of the cathode rays. The measured values of the cross section agree fairly well with calculations based on the Born approximation, but the agreement is not within the estimated experimental error.
Maternal perceptions of lead poisoning in children with normal and elevated lead levels

Abstract Introduction: The purpose of this study was to examine mothers' perceptions of the severity and susceptibility of their children to lead poisoning and to determine if a correlation existed between mothers' knowledge of lead poisoning and their children's blood lead levels. It was thought that mothers of children with lead poisoning (lead levels ≥10 μg/dL) would score lower on a test of their perceptions and knowledge of lead poisoning than would mothers of children with normal lead levels (lead levels ≤9 μg/dL). Method: A cross-sectional study comparing scores of a questionnaire completed by mothers whose children had elevated blood lead levels and mothers whose children had normal blood lead levels was conducted. Results: No difference was found in the median test score between the 2 groups. For the correct responses on a question-by-question comparison, significant differences existed between groups; however, the percentage of correct responses was not always greater for the mothers of children with normal blood lead levels. Discussion: Mothers' perceptions and knowledge of lead poisoning were not associated with their children's blood lead levels.
Depiction of Infarct Frequency Distribution by Computer-Assisted Image Mapping in Rat Brains With Middle Cerebral Artery Occlusion Comparison of Photothrombotic and Intraluminal Suture Models

Background and Purpose Histopathologic analysis of experimental brain damage has traditionally been performed by measuring areas of infarction and/or selective neuronal alterations on a section-by-section basis in individual animals. For series containing multiple replicate animals, quantitation of tissue injury is typically performed at similar coronal levels throughout an experimental group. A means of facilitating pictorial group comparisons of these histopathologic alterations between different series of replicate studies is highly desirable. Methods We introduce a newly designed approach to achieve this goal, based on a linear affine transformation that is used to map corresponding sections at the same anatomic level into a common template to yield a frequency distribution map depicting the aggregate data set. We have applied this approach to compare the histopathologic features of two models of middle cerebral artery (MCA) occlusion in rats: (1) photothrombotically induced permanent distal MCA occlu...
Distributed energy management algorithm for large-scale wireless sensor networks

In battery-constrained wireless sensor networks, it is important to employ effective energy management while maintaining some level of network connectivity. Viewing this problem from a percolation-based connectivity perspective, we propose a fully distributed energy management algorithm for large-scale wireless sensor networks. This algorithm allows each sensor to probabilistically schedule its own activity based on its node degree. This mechanism is modelled by a degree-dependent dynamic site percolation process on random geometric graphs. We specify the conditions under which the resulting network is guaranteed to be percolated at all the time. We further study the delay performance of the proposed energy management algorithm by modelling the problem as a degree-dependent first passage percolation process on random geometric graphs.