cssi/SciSciGPT-SciSciNet huggingface dataset:
Comprehensive Analysis of Photoreceptor Gene Expression and the Identification of Candidate Retinal Disease Genes

To identify the full set of genes expressed by mammalian rods, we conducted serial analysis of gene expression (SAGE) by using libraries generated from mature and developing mouse retina. We identified 264 uncharacterized genes that were specific to or highly enriched in rods. Nearly half of all cloned human retinal disease genes are selectively expressed in rod photoreceptors. In silico mapping of the human orthologs of genes identified in our screen revealed that 86 map within intervals containing uncloned retinal disease genes, representing 37 different loci. We expect these data will allow identification of many disease genes, and that this approach may be useful for cloning genes involved in classes of disease where cell type-specific expression of disease genes is observed.
Myocardin-related transcription factors A and B are key regulators of TGF-β1-induced fibroblast to myofibroblast differentiation

Myofibroblasts are contractile, smooth muscle-like cells that are characterized by the de novo expression of smooth muscle α-actin (SMαA) and normally function to assist in wound closure, but have been implicated in pathological contractures. Transforming growth factor β-1 (TGF-β1) helps facilitate the differentiation of fibroblasts into myofibroblasts, but the exact mechanism by which this differentiation occurs, in response to TGF-β1, remains unclear. Myocardin-related transcription factors A and B (MRTFs, MRTF-A/B) are transcriptional co-activators that regulate the expression of smooth muscle-specific cytoskeletal proteins, including SMαA, in smooth muscle cells and fibroblasts. In this study, we demonstrate that TGF-β1 mediates myofibroblast differentiation and the expression of a contractile gene program through the actions of the MRTFs. Transient transfection of a constitutively active MRTF-A induced an increase in the expression of SMαA and other smooth muscle-specific cytoskeletal proteins, and an increase in myofibroblast contractility, even in the absence of TGF-β1. MRTF-A/B knockdown, in TGF-β1-differentiated myofibroblasts, resulted in decreased smooth muscle-specific cytoskeletal protein expression levels and reduced contractile force generation, as well as a decrease in focal adhesion size and number. These results provide direct evidence that the MRTFs are mediators of myofibroblast differentiation in response to TGF-β1.
Tolerance to fenfluramine anorexia: fact or fiction?

Recent findings in this laboratory with regard to tolerance to fenfluramine anorexia are reviewed with respect to generality of the behavioural phenomenon. A systematic relationship between initial body weight and fenfluramine-induced weight change in rats is described. The possible roles of peripheral factors in fenfluramine anorexia and tolerance, including gastric emptying and peripheral serotonin, are discussed. The role of central factors is also considered. It appears that fenfluramine, and possibly other anorectic agents have multiple sites of action and affect multiple behaviours. Some clinical implications are noted.
Nucleon-nucleon potential and minimal relativity

Abstract The effects of relativistic elastic unitarity on low-energy nucleon-nucleon scattering and the binding energy of nuclear matter are investigated. Relativistic unitarity is found to increase the nuclear matter binding by approximately 0.5 MeV per particle over the value obtained for a non-relativistic potential having a similar shape and identical phase shifts.
CHANGES IN GRAPE FIRMNESS DURING MATURATION

Puncture force with skin on, puncture force with skin off, deformability, and ˚Brix were measured on six cultivars of grapes grown in northeastern USA as they matured over a six week period. Deformability increased steadily throughout the maturation period. ˚Brix increased rapidly following veraison and then continued to increase at a slow rate. Both puncture forces decreased rapidly at veraison and then continued to decrease at a slower rate. The puncture force with skin on was always much higher than puncture force with skin off. All the physical properties correlated well with each other and with ˚Brix (with a few exceptions). The puncture test with skin on usually gave the highest correlation with ˚Brix. It could probably be used as an alternative test to ˚Brix or as a confirmatory test to supplement the ˚Brix reading.
Potential biocontrol of Sclerotinia homoeocarpa and Bipolaris sorokiniana on the phylloplane of Poa pratensis with strains of Pseudomonas spp.

Four Pseudomonas strains were evaluated for their ability to control Sclerotinia homoeocarpa and Bipolaris sorokiniana on the phylloplane of Poa pratensis (Kentucky bluegrass). The strains evaluated were Pseudomonas fluorescens (PSD-4, PSD-5, PSD-6) and Pseudomonas lindbergii (PSD-42). All evaluations were conducted on the upper epidermis of intact attached leaves of Poa pratensis and antagonism was measured as the ability of strains of Pseudomonas to prevent chlorophyll loss from leaves inoculated with either S. homoeocarpa or B. sorokiniana. All strains prevented infection and loss of chlorophyll following inoculation with S. homoeocarpa. Only P. lindbergii (PSD-42) was antagonistic to B. sorokiniana. None of the P. fluorescens strains controlled disease induced by B. sorokiniana.
Sequentially rejective pairwise testing procedures

Abstract Holm's (1979) sequentially rejective procedure was developed for families of hypotheses which allow ‘free combinations’. Two modifications of Holm's procedure for the family of pairwise hypotheses were discussed by Shaffer (1984, 1986). However, the more powerful modification is only illustrated for the case k = 4 means and not discussed further because of the prohibitive computational effort it requires even when k is moderate. We first note that Shaffer's powerful sequentially rejective procedure is equivalent to Peritz's (1970) closed testing scheme when a natural relation holds between the corresponding critical values. This raises the question of whether conditions exist under which a computationally efficient algorithm can be derived for implementing that procedure. We identified conditions under which a very efficient algorithm is given. While the worst case complexity of Peritz's procedure grows exponentially with k , that of the given algorithm is only a fourth degree polynomial in k . The given conditions are quite restrictive but extremely simple to test in each particular case. This becomes important when k is large since procedures of exponential complexity are not implemented in such cases (and sometimes even when k is moderate). In developing the algorithm we use a graph theory approach and provide some new results which are potentially of independent theoretical interest.
Antagonistic Effect of Inositol Pentakisphosphate on Inositol Triphosphate Receptors

Abstract We present evidence that inositol 1,3,4,5,6-pentakisphosphate acts as an antagonist of inositol triphosphate receptors in vitro by dampening the activity of Ca2+-mobilizing inositol phosphates. This antagonism bears physiological significance as cells maintain substantial quantities of this phosphoinositol in the cytosol, especially during cell differentiation or proliferation. Over a concentration range from 30 to 150 μM, this pentakisphosphate causes a two- to five-fold increase in the EC50values of inositol 1,4,5-trisphosphate and other active phosphoinositols in effecting Ca2+efflux from brain microsomes. This specific inhibition results from competitive receptor binding, and is not noted with inositol hexaphosphate or related metabolites at comparable concentrations. Thus, inositol 1,3,4,5,6-pentakisphosphate in concert with other allosteric modulators may constitute an integral component for the receptor regulation.
Ontologies for enterprise knowledge management

Several challenges exist related to applying ontologies in real-world environments. The authors present an integrated enterprise-knowledge management architecture, focusing on how to support multiple ontologies and manage ontology evolution.
Effects of x-irradiation on the hypothalamus: a possible explanation for the therapeutic benefits following x-irradiation of the hypophysial region for pituitary dysfunction.

INTRODUCTION THE primary purpose of this report is to direct attention to certain histologic changes observed in the nuclear masses of the hypothalamus of the monkey, following x-irradiation, which may explain in part some of the therapeutic benefits obtained by x-irradiation of the hypophysial region for a number of clinical disorders thought to be due to pituitary dysfunction. For the past four years studies have been in progress to determine and analyze the effects of high energy x-rays on the central nervous system of primates (1, 2), and during the course of such studies it was noted that the paraventricular and supraoptic nuclei of the hypothalamus were rather responsive to irradiation. Since the normal hypophysis has been frequently reported as being radio-resistant and, in view of the increasing evidence that the hypothalamus (3–6) mediates or controls many of the functions of the pituitary body, one may then postulate that the therapeutic benefits reported to follow x-irradiation of the hypophysi...
Evaluation of fatty acid methyl ester profile and amplified fragment length polymorphism analyses to distinguish five species of Phytophthora associated with ornamental plants

Fatty acid methyl ester (FAME) profiles and amplified fragment length polymorphisms (AFLPs) were evaluated as tools for identifying species of Phytophthora. Five isolates of each of Phytophthora ca...
The Lick Observatory charge-coupled device /CCD/ and controller

A description is given of a flexible microprocessor-based controller for charge-coupled device two-dimensional detectors. It is noted that the controller can operate under manual control or as a slave to a remote computer linked by coaxial cable. The system is discussed, together with data taken at the telescope and in the laboratory. The flexibility of the controller derives from its modular form and from the use of a programmable 8-bit microprocessor to control and sequence the electronic logic. The electronic circuits for such functions as signal processing, clock sequencing, voltage level adjustment, and temperature control are on small individual plug-in cards, making future improvements and changes simple. The software of the microprocessor is stored in erasable, programmable, read-only memory. Among the limitations of the controller is a scan speed of roughly 35 microsec per pixel.
KTP laser ablation of Barrett's esophagus after anti-reflux surgery results in long-term loss of intestinal metaplasia

Background: Efforts to ablate Barrett's epithelium have met with mixed results. We report the long-term follow-up evaluation of the preliminary cohort of patients who underwent thermal ablation of Barrett's epithelium with the potassium–titanyl–phosphate (KTP) laser after anti-reflux surgery. Methods: Nine patients with intestinal metaplasia (IM) of the esophagus underwent fundoplication (7 laparoscopic Nissen, 1 laparoscopic Toupet, 1 open Nissen) between May 1993 and October 1994. Three patients had an IM less than 3 cm long (33%). One year after the operation, all the patients were symptom free, had discontinued medications, and had a normal 24-h pH study. From June 1995 to February 1996, these patients underwent a median of two (range, 1–5) endoscopic procedures with directed mucosal ablation using the KTP laser. A comparative cohort of 21 patients (IM length, <3cm; 38%) treated during the same period with fundoplication alone served as a control. The patients were followed prospectively with annual or biennial endoscopy and biopsy. All the patients were contacted by mail, telephone, or clinic visit annually to determine symptomatic and quality-of-life outcome of antireflux surgery. Results: The mean follow-up period was 6.8 years (range, 6–7.5 years). At this writing, the study patients are alive and well. Eight of the patients have experienced histologic loss of IM (89%) according to their last biopsy result. One patient has had regression of low-grade dysplasia to IM. The patients treated with fundoplication alone had a mean follow-up period of 5.6 years (range, 4.7–7.2 years). On the basis of the last biopsy result, 7 of 21 patients (33%) had no evidence of IM. Conclusions: A program of tailored antireflux surgery followed by thermal mucosal ablation causes a loss of IM in a majority of patients with Barrett's esophagus. This may represent a significant improvement in histologic outcome over that of treatment with fundoplication alone (p = 0.007 Fisher's exact test).
Habenular lesions produce decrements in feminine, but not masculine, sexual behavior in rats.

Bilateral electrolytic lesions in the habenula or stria medullaris thalami resulted in disruption of estrogen- and progesterone-evoked feminine sexual behaviors of ovariectomized female rats. Subjects with habenular or stria medullaris lesions, compared to sham-operated or unoperated animals, displayed less soliciting behaviors and more rejecting or minimal responses. The effect of lesions upon androgen-evoked masculine behavior of ovariectomized female rats was unclear, but a second experiment failed to reveal any effect of habenular lesions upon the masculine sexual behavior of intact male rats, nor was there any evidence of gonadotropic dysfunction. The results suggest that a system involving the habenula and stria medullaris is involved in the mediation of feminine, but not masculine, sexual behavior in the rat.
Changes in axonal transport in neurones of Asterias vulgaris and Asterias forbesei produced by colchicine and dimethyl sulfoxide.

Gas flow analysis, autoradiography, and electron microscopy were performed on radial nerve cords of sea stars injected intragastrically with [14C] leucine tracer, a precursor of axonal proteins. Neurotubules, neurofilaments, and axonal transport were demonstrated for the first time in sea stars. This transport occurred at two rates (fast phase: 240–480 mm/da, slow phase: 20–40 mm/da) moving in both the cellulifugal and centripetal directions. The rate in the centripetal direction was slightly slower. Displacement of peaks of radioactivity appeared cyclic.Transneuronal transport apparently occurred between several groups of neurones suggesting the possibility of metabolic communication, perhaps across the synapse, between groups of neurones or even areas of the nervous system. Regenerating nerve cords demonstrated an increase in the rate (400–600 mm/da) and quantity (6–11 times as much) of label transported to cord termini.
Functional Inference in Frailty Measurement Error Models for Clustered Survival Data Using the SIMEX Approach

We consider frailty models for clustered survival data in the presence of measurement errors in covariates. We first show that when the measurement error is accounted for in a full likelihood analysis but the distribution of the unobserved covariate is misspecified, the maximum likelihood estimators are asymptotically biased, especially for the variance component, whose bias can be substantial. We then discuss making inference using functional estimation via the SIMEX method where no distribution of the unobserved error-prone covariate is assumed. The SIMEX method is easy to implement by repeatedly fitting standard frailty models. We study the asymptotic properties of the SIMEX estimates and show that they are consistent and asymptotically normal. In simulation studies, we compare the SIMEX method and the likelihood method in terms of efficiency and robustness. We also propose a SIMEX score test for the variance component to test for the within-cluster correlation and evaluate its performance through simu...
Use of transferable Nicotiana tabacum L. microsatellite markers for investigating genetic diversity in the genus Nicotiana.

The recent development of microsatellite markers for tobacco, Nicotiana tabacum L., may be valuable for genetic studies within the genus Nicotiana. The first objective was to evaluate transferability of 100 N. tabacum microsatellite primer combinations to 5 diploid species closely related to tobacco. The number of primer combinations that amplified scorable bands in these species ranged from 42 to 56. Additional objectives were to assess levels of genetic diversity amongst available accessions of diploid relatives closely related to tobacco (species of sections Sylvestres and Tomentosae), and to evaluate the efficacy of microsatellite markers for establishing species relationships in comparison with existing phylogenetic reconstructions. A subset of 46 primer combinations was therefore used to genotype 3 synthetic tobaccos and an expanded collection of 51 Nicotiana accessions representing 15 species. The average genetic similarity for 7 diverse accessions of tobacco was greater than the average similarity...
An evaluation of haptic descriptions for audio described films for individuals who are blind

Narrations of visual content, or audio descriptions, enhance the accessibility of video media for individuals who are blind. While the adoption of this assistive technology continues to broaden, audio descriptions have several limitations: they often lack detail (i.e., are abridged) to fit within dialogue-free gaps, and are difficult to use in fast-paced sequences or scenes of continuous dialogue. Haptic descriptions offer a promising augmentation to audio descriptions by conveying information through the sense of touch. This work presents audio-haptic descriptions with a user evaluation showing how haptic descriptions can add relevant information to films for improved comprehension.
THE DOMINANT ROLE OF THE EPIDERMIS IN LEAVES OF ADIANTUM

the fertile ovule lies in the locule of the carpel opposite, not in the locule of its own carpel. Vestigial ovules are usually present in the abortive carpels and are usually absent in the carpel containing the fertile ovule. The carpel with the welldeveloped locule, therefore, is usually sterile, though it contains the single fertile ovule in the flower. The vascular supply of the ovary consists of five peripheral bundles and a central bundle. The central bundle usually divides in the vicinity of the ovule attachnent, primitively, into three ventral bundles and an ovular bundle. Reduction stages occur in the various species showing the loss of one, then both sterile ventral bundles, followed eventually bv the disappearance of the fertile ventral bundle. The ovular bundle mav be double at its origin, but it fuses before entering the ovule. The ovular supply, therefore, like that of the fertile ovules in the Linnaeeae, is douHle. Some species show vestiges of ovular traces to some of the abortive ovules. Lateral and dorsal carpellary traces for the three carpels are variously derived from the peripheral and central bundles. Four of the peripheral bundles divide at the top of the ovary. In all, ten bundles are formed,-five petal traces, five stamen-sepal bundles. In manv of the species, flowers occur with no fertile ovule, though one abortive ovule is relatively betterdeveloped than the rest. The supply is simnilar to that of the normal ovary. The relatively welldeveloped abortive ovule is delimited in the upper part of the ovary around thee ovular bundle in the center. It emerges in the center of a 3-lobed locule which contains even more reduced vestigial ovules attached to the three placentae. It is evident that there has been enlargement and atrophy of organs, and adnation and cohesion of parts and their vascular supply in the evolution of the genus. Reduction stages are found in the dorsal and marginal carpellary supply; the supply to fertile and abortive ovules; the number, position, and development of abortive ovules; the peripheral bundles; and the sepal traces. Comparative study of the internal morphology and vascular anatomy of the flower indicates that V. Sieboldii is the most primitive; FT. Opulus, the most advanced. Also primitive are V. Cartes i, V. Lantana and V. dentatum. More advanced are V. rhitidophyllum, V. cassinoides, V., acerifolium, V. tri.lobum anid others.
Factor Model for Stress-Testing with a Contingent Claims Model of the Chilean Banking System

This paper derives risk indicators for the major Chilean banks based on contingent claims analysis, an extension of Black-Scholes-Merton option-pricing theory. These risk indicators are clearly tied to macroeconomic and financial developments in Chile and outside, but bank responses are highly heterogeneous. To reduce the number of variables linked to the banks' risk to a tractable number, we apply principal component analysis. Vector autoregressions of risk indicators with the most significant factors show strong ties from financial markets and regional developments. Impulse response functions from these factors are derived, which allow for scenario testing. The scenarios derived in the paper illustrate how the magnitude and persistence of responses of bank credit risk can vary across banks in the system.
Volume image registration by template matching

Abstract A template-matching approach to registration of volumetric images is introduced. The process automatically selects a dozen highly detailed and unique templates (cubic or spherical subvolumes) from one image and locates the templates in another image of the same scene. The centroids of the corresponding templates are used as corresponding control points and the best four correspondences that minimize an error criterion are used to determine the translational and rotational parameters needed to register the images. Use of different similarity measures in template matching and determination of coordinates of corresponding control points with subpixel accuracy are also discussed.
Amphetamine inhibition of α-bungarotoxin binding at the mouse neuromuscular junction

Abstract Amphetamine inhibited neuromuscular transmission and prevented the irreversible blockade produced by α-bungarotoxin (α-BGT) in the isolated mouse phrenic nerve-diaphragm preparation. Similarly, amphetamine (1.35 × 10 −4 to 3 × 10 −3 M) inhibited the binding of 125 I-α-BGT to mouse hemidiaphragms in a concentration-dependent manner; (+)-amphetamine was found to be twice as potent as its (-)-isomer with respect to inhibition of 125 I-α-BGT binding. It is suggested that amphetamine binds to the nicotinic, cholinergic receptor of skeletal muscle and may produce weakness and paralysis in amphetamine overdosage.
Racial Differences in Ambulatory Blood Pressure and Echocardiographic Left Ventricular Geometry

We examined the racial differences in left ventricular (LV) geometric pattern in relation to 24-hour ambulatory blood pressure (BP) monitoring and the presence or absence of a nocturnal BP dip. Our study confirms the blunting of nocturnal BP dip among black hypertensives. Body mass index, rather than race, was a major determinant of left ventricular hypertrophy. We did not observe a difference in prevalence of left ventricular hypertrophy by race. However, left ventricular adaptation to hypertension differed in hypertensive black and white individuals; whereas most of the white patients with Stage 1-2 hypertension had a normal ventricular pattern, LV concentric remodeling and concentric hypertrophy were the most common adaptive ventricular patterns in blacks with Stage 1-2 hypertension. A six-fold higher prevalence of concentric remodeling was observed in blacks as compared with whites. The impaired nocturnal BP dip in blacks may contribute to the different hemodynamic pattern. Determinants of myocardial oxygen consumption were significantly higher in black hypertensives.
Modeling of Thermoelectric Effects in Phase Change Memory Cells

Thermoelectric effects on phase change memory elements are computationally analyzed through 2-D rotationally symmetric finite-element simulations of reset operation on a Ge2Sb2Te5 (GST) mushroom cell with 10-nm critical dimension. Temperature-dependent material parameters are used to determine the thermoelectric contributions at the junctions (Peltier heat) and within GST (Thomson heat). Thermal boundary resistances at the GST interfaces enhance the Peltier heat contribution. Peak current densities and thermal gradients are in the order of 250 MA/cm2 and 50 K/nm. Overall, thermoelectric effects are shown to introduce significant voltage polarity dependence on the operation dynamics, peak temperatures, thermal gradients, volume of the molten region, energy required, and resistance contrast. Resistance contrasts of ~ 8.8 × 103 were realized with 155 μA for the positive polarity and 245 μA for the negative polarity.
The spectral maps of dynamic speckle patterns: A new perspective to look at the motion-induced spatiotemporal cross-correlation

Abstract We introduce the spectral map method as a means to visualize the spatiotemporal correlation in dynamic speckles. Dynamic speckle patterns of moving diffuse objects are Fourier transformed to construct spectral maps in spatial domain (r-space) and spatial-frequency domain (k-space). The periodic patterns in r-space spectral maps demonstrate the spatiotemporal cross-correlation induced by the directional motions. To resolve the spectral bands in k-space spectral maps, and to observe the concomitant appearance of the periodic pattern in r-space spectral maps, the frequency must exceed the minimum values given by the speckle size and the speed. A bigger speckle size helps to reveal fast dynamics, and to ease the requirement on the minimum frequency. The transition from ordered translational speckles to chaotic boiling speckles at different speeds and speckle sizes is elucidated in connection with the change observed in spectral maps.
Bactericidal activities of teicoplanin, vancomycin, and gentamicin alone and in combination against Staphylococcus aureus in an in vitro pharmacodynamic model of endocarditis.

We adapted an in vitro pharmacodynamic model of infection to incorporate simulated endocardial vegetations. The bactericidal activities of teicoplanin, vancomycin, gentamicin, and various combinations of these drugs were studied against a strain of methicillin-susceptible Staphylococcus aureus obtained from a patient being treated for endocarditis at Detroit Receiving Hospital. Bacteria were grown overnight, concentrated, and added to a mixture of cryoprecipitate (80%) and thrombin (10%) to achieve approximately 5 x 10(9) CFU/g. Fibrin clots (8 to 10) were suspended into the model, removed at 24, 48, and 72 h in duplicate, weighed, and homogenized in 1.25% trypsin. Control experiments were conducted to characterize the growth kinetics. The following antibiotics were administered to simulate the pharmacokinetics of the drugs in humans: teicoplanin at 3 and 15 mg/kg of body weight, vancomycin at 15 mg/kg, and gentamicin at 1 mg/kg. Fibrin clot samples used to detect resistance were plated on antibiotic-containing tryptic soy agar plates. For the teicoplanin and vancomycin regimens, protein binding to cryoprecipitate, thrombin, and fibrin clot was determined to be 32, 43, and 50% and 26, 28, and 29%, respectively. In comparison with no treatment, vancomycin or teicoplanin at 15 mg/kg or either of these regimens combined with gentamicin significantly reduced bacterial counts (P
1H NMR spectroscopic characterization of solutions of Sepia melanin, Sepia melanin free acid and human hair melanin.

A 1 H nuclear magnetic resonance study of Sepia melanin, Sepia melanin free acid (Sepia MFA) and human hair melanin was carried out in deuterium oxide solution at pH 10-11. The empirical formula of Sepia MFA was calculated and used to estimate the number of protons in the aromatic region of the Sepia MFA polymeric chain and to suggest a possible monomeric unit profile.
Proton-bombardment isolated GaAlAs/GaAs charge-coupled devices

Proton bombardment is used for the first time as a channel isolation technique to fabricate buried channel homojunction charge-coupled devices (c.c.d.s) of n-GaAs channel on GaAs substrate and heterojunction c.c.d.s of n-Ga1−xAlxAs on GaAs. The c.c.d. structure is a Schottky-barrier gate buried channel 3-phase device with 30 transfer gates. The channel-stop bombardment was carried out at room temperature with an energy of 200 keV and a total dose of 1015/cm2. The c.c.d.s were tested with electrical charge injection and direct readout. The charge transfer efficiency was found to be greater than 0.999 per transfer for both GaAs and GaAlAs. The proton-bombardment isolated devices were compared with similar devices using mesa isolation and were found to perform similarly.
Towards Role-Based Authorization for OSGi Service Environments

OSGi framework enables diverse devices to conveniently establish a local area network environment such as homes, offices, and automobiles. Access control is one of the crucial parts which should be considered in such emerging environments. However, the current OSGi authorization mechanism is not rigorous enough to fulfill security requirements involved in dynamic and open OSGi environments. This paper provides a systematic way to adopt a role-based access control approach in OSGi environments. We demonstrate how our authorization framework can achieve important RBAC features and enhance existing primitive access control modules in OSGi service environments.
Expanding the Dialog on the Peopling of the Americas

A major goal of PaleoAmerica is to provide various stakeholders involved in the study of the peopling of the New World with a mouthpiece, to ensure that scientific enquiry is international and inte...
Acute Overexpression of Myc in Intestinal Epithelium Recapitulates Some but Not All the Changes Elicited by Wnt/β-Catenin Pathway Activation

The Myc transcription factor is a potent inducer of proliferation and is required for Wnt/β-catenin signaling in intestinal epithelium. Since deregulation of the Wnt/β-catenin pathway is a prerequisite for nonhereditary intestinal tumorigenesis, we asked whether activation of Myc recapitulates the tumorigenic changes that are driven by constitutive Wnt/β-catenin pathway signaling following adenomatous polyposis coli (APC) inactivation. Using mice in which expression of MycERTAM, a reversibly switchable form of Myc, is expressed transgenically in intestinal epithelium, we define the acute changes that follow Myc activation as well as subsequent deactivation. Myc activation reversibly recapitulates many, but not all, aspects of APC inactivation, including increased proliferation and apoptosis and loss of goblet cells. However, whereas APC inactivation induces redistribution of Paneth cells, direct Myc activation triggers their rapid attrition. Moreover, direct Myc activation engages the ARF/p53/p21cip1 tumor suppressor pathway, whereas deregulation of Wnt/β-catenin signaling does not. These observations illustrate key differences in oncogenic impact in intestinal epithelium of direct Myc activation and indirect Myc activation via the Wnt/β-catenin pathway. Furthermore, the in situ dedifferentiation of mature goblet cells that Myc induces indicates a novel cross talk between the Wnt/β-catenin and Notch signaling pathways.
Advances in Quantifying Air-Sea Gas Exchange and Environmental Forcing*

The past decade has seen a substantial amount of research on air-sea gas exchange and its environmental controls. These studies have significantly advanced the understanding of processes that control gas transfer, led to higher quality field measurements, and improved estimates of the flux of climate-relevant gases between the ocean and atmosphere. This review discusses the fundamental principles of air-sea gas transfer and recent developments in gas transfer theory, parameterizations, and measurement techniques in the context of the exchange of carbon dioxide. However, much of this discussion is applicable to any sparingly soluble, non-reactive gas. We show how the use of global variables of environmental forcing that have recently become available and gas exchange relationships that incorporate the main forcing factors will lead to improved estimates of global and regional air-sea gas fluxes based on better fundamental physical, chemical, and biological foundations.
Two blackbody radiometers of high accuracy.

Two cavity-type radiometers have been developed, based on first principles, having the capability of measuring an irradiance with an indicated error 0.3%. The prerequisites for this accuracy are a measured aperture area, a measurement of electric voltages, and an effective absorptance of its blackbody cavity from 0.998 to 0.999 throughout the uv, visible, and ir spectral ranges. The first cavity-type radiometer is designed to operate only in a vacuum of <10−5 Torr and to measure intensities from 10 mW cm−1 to 300 mW cm−2. By using this radiometer in an evacuated cold chamber, an experimental determination of the Stefan-Boltzmann constant is obtained at a value that differs from the theoretical value by 0.3%, which indicates the degree of confidence that can be expected in measurements made with blackbody cavity radiometers. The second type of radiometer is designed to operate in either air or vacuum. Although its aperture opening is windowless, it is unaffected by wind. The range of intensities accurately measurable is from about 10 mW cm−2 to 800 mW cm−2; the indicated accuracy is also 0.3%.
Strategic knowledge management research: tracing the co‐evolution of strategic management and knowledge management perspectives

This article traces the evolution of strategic management and knowledge management research during the past four decades with particular emphasis on the role of knowledge in interorganizational collaborative arrangements. By outlining the main strategic management perspectives in contemporary business literature and combining them with current knowledge management perspectives, an indication of the evolution of research pertaining to strategic knowledge management emerges. It is shown that most of the current strategic knowledge management research is conducted within the existing paradigms of strategic management. A criticism of this is offered and the article concludes by offering a new, more dynamic perspective of knowledge management, focusing on the synergies of knowledge‐related capabilities in explaining the formation and economic justification of strategic collaborative arrangements.
Automated breathing motion tracking for 4D computed tomography

4D-CT is being developed to provide breathing motion information for radiation therapy treatment planning. Potential applications include optimization of intensity-modulated beams in the presence of breathing motion and intra-fraction target volume margin determination for conformal therapy. A major challenge of this process is the determination of the internal motion (trajectories) from the 4D CT data. Manual identification and tracking of internal landmarks is impractical. For example, in a single couch position, 512 /spl times/ 512 /spl times/ 12 pixel CT scans contains 3.1/spl times/10/sup 5/ voxels. If 15 of these scans are acquired throughout the breathing cycle, there are almost 47 million voxels to evaluate necessitating automation of the registration process. The natural high contrast between bronchi, vessels, other lung tissue offers an excellent opportunity to develop automated deformable registration techniques. We have been investigating the use motion compensated temporal smoothing using optical flow for this purpose. Optical flow analysis uses the CT intensity and temporal (in our case tidal volume) gradients to estimate the motion trajectories. The algorithm is applied to 3D image datasets reconstructed at different percentiles of tidal volumes. The trajectories can be used to interpolate CT datasets between tidal volumes.
Radiation Dose Management: Part 2, Estimating Fetal Radiation Risk From CT During Pregnancy

OBJECTIVE. The purpose of this article is to review fetal radiation doses and associated risks resulting from CT performed during pregnancy. The scanning parameters that influence dose and the techniques for estimating and reducing dose are explained. CONCLUSION. Fetal radiation doses for CT examinations in which the fetus is not directly imaged???for example, head or chest CT???are minimal and need not figure in the risk-benefit analysis to perform the examination. In contrast, radiation dose should be considered with abdominopelvic CT because the fetus is likely to be exposed directly to the scanning beam. Safe implementation of CT in this setting requires an understanding of the factors influencing radiation dose. With this knowledge, when a risk-benefit analysis in a given clinical situation favors imaging using CT, the radiologist need not withhold or delay the examination and can achieve diagnostic-quality images while reducing radiation exposure.
Ferrous Ion-Dependent l-Serine Dehydratase from Clostridium acidiurici

Abstract l-Serine dehydratase from Clostridium acidiurici was purified 400-fold. The enzyme required activation by catalytic amounts of ferrous ion and a thiol reducing agent before the addition of substrate. Several cations tested were unable to substitute for divalent iron. The reducing agent of choice was dithiothreitol. The activation was presumed to result in the formation of an iron-enzyme complex, because once activated the enzyme retained essentially full activity in a reaction mixture not supplemented with iron or reducing agent. The reaction with substrate was carried out at pH 8.4 in phosphate buffer and was specific for l-serine. The presence of pyridoxal phosphate as coenzyme was indicated by absorption maxima at 330 and 420 nm and fluorescence maxima at 390 and 520 nm.
Equatorially generated ULF waves as a source for the turbulence associated with ion conics

Consideration is given to the possible source of low frequency turbulence on closed field lines in the central plasma sheet, which is used to explain ion heating and conic formation. Observations show that ion distributions in the equatorial region are often anisotropic and that these distributions excite ion cyclotron waves below the proton gyrofrequency and near the harmonics of the hydrogen cyclotron frequency. It is suggested that downcoming right-hand circularly polarized waves acquire a left-hand circularly polarized component at the crossover frequency and may tunnel through a stop zone to altitudes where they contribute to ion heating.
Creating Asset Accounts For A Commercial Fishery Out Of Equilibrium: A Case Study Of The Atlantic Sea Scallop Fishery

This paper demonstrates a methodology for constructing asset accounts for a commercial fishery in which the stock, harvest, and effort level are out of sustainable equilibrium. The paper adopts the framework used by the U.S. Department of Commerce Bureau of Economic Analysis in its preliminary 1993 Integrated Economic and Environmental Accounts and follows methodologies recommended by the National Research Council committee constituted to review those efforts. The accounts were constructed for the period 1985 to 1995 for the Atlantic sea scallop fishery, a significant commercial fishery, using information obtained with the cooperation of the National Marine Fisheries Service from existing databases constructed for management purposes. No significant additional data collection was required for the purpose of this study. Differences between the net rent and user cost values of the stocks over this period indicate the inefficient exploitation of immature scallop populations.
Response analysis for multiple symptoms revealed differences between arms of a symptom management trial

Abstract Objective To describe the methodology of evaluating the response of cancer patients to interventions directed at lowering severity of multiple symptoms, and to compare two arms of a symptom management trial to determine factors associated with response and time to response. Study Design and Setting Randomized trial comparing a nurse-assisted symptom management (NASM) cognitive-behavioral intervention with an automated telephone symptom management (ATSM). Patients in both arms received six intervention contacts over 8 weeks. Analyses of the intervention contact data for 190 patients in NASM arm and 164 patients in the ATSM arm were conducted. Severities of 15 cancer-related symptoms were assessed at each intervention contact, and an anchor-based definition of response was adopted. Analyses were carried out using generalized estimating equations and Cox marginal proportional hazard models. Results When compared with patients in the NASM, patients in the ATSM had better response to manage anxiety, depression, poor appetite, cough, and fatigue. NASM was more successful in managing cancer pain. Response and time to response were associated with several patient and disease characteristics. Conclusion The approach described here presents an analytic and clinical improvement over methods that examine each symptom separately or use summed scores of severity.
Streamers and diffuse glow observed in upper atmospheric electrical discharges

A telescopic imaging system was designed to observe fine structure in high-altitude lightning-related electrical discharges known as "sprites". Hundreds of sprites were observed and much of the fine structure can be categorized in terms of streamer and diffuse glow discharges. A streamer/diffuse glow transition occurs at varying altitudes and is dependent on the ambient mesospheric/lower ionospheric conductivity profile. Both stationary and dynamic beading is observed and this feature is currently unexplained by prevailing sprite theories.
γ-Aminobutyric Acid (GABA)-A Function and Binding in the Paraventricular Nucleus of the Hypothalamus in Chronic Renal-Wrap Hypertension

The goal of this study was to determine whether γ-aminobutyric acid (GABA)ergic transmission and GABA binding are altered in chronic renal-wrap hypertension. Three groups of hypertensive and sham-operated rats were prepared for separate protocols. Four weeks later, the animals were prepared with femoral artery catheters for the measurement of mean arterial pressure. In all groups, blood pressure was significantly higher in the renal-wrapped animals. In the first study, bilateral microinjection of the GABA-A antagonist, bicuculline (50 pmol/site), into the paraventricular nucleus of the hypothalamus (PVN) caused a greater increase in arterial pressure (21.9±1.4 versus 16.7±1.8 mm Hg, P P =0.064) in hypertensive rats. [ 3 H]Flunitrazepam was used to measure binding to the GABA-A receptor. Magnocellular neurons and the adjacent medial parvicellular neurons had more intense binding compared with the remainder of the PVN. B max was greater for the higher density binding area; the K d value was less in the high-density region. There were no differences in these parameters between normotensive and hypertensive animals. Competitive reverse transcription–polymerase chain reaction was used to measure the expression of mRNA for the α 1 subunit of the GABA-A receptor. No difference was observed in the mRNA between renal-wrapped and sham-operated rats. In summary, inhibition of GABA-A receptors in the PVN is augmented in the chronic phase of hypertension and is unrelated to a change in the expression of the number or affinity to the receptor. These findings suggest that the greater GABAergic activity is the result of an increase in GABA release in the PVN in chronic renal-wrap hypertension.
Does the Dose Matter

Pharmacokinetic/pharmacodynamic (PK/PD) parameters, such as the ratio of peak to minimum inhibitory concentration (peak/MIC ratio), ratio of 24-hour area under the curve to MIC (24-h AUC/MIC ratio), and the time above MIC, are good indicators of the drug dose-organism interaction. Time above the MIC is the important determinant of the activity of beta-lactams, macrolides, clindamycin, and linezolid. Free drug serum levels of these drugs should be above the MIC for at least 40%-50% of the dosing interval to produce adequate clinical and microbiological efficacy. Peak/MIC and 24-h AUC/MIC ratios are major determinants of the activity of aminoglycosides and fluoroquinolones. In general, peak/MIC ratios should exceed 8 and 24-h AUC/MIC values should be >100 to successfully treat gram-negative bacillary infections and to prevent the emergence of resistant organisms during therapy. The successful treatment of pneumococcal infections with fluoroquinolones and azithromycin appear to require 24-h AUC/MIC ratios of only 25-35. Mutation prevention concentrations are being reported for various fluoroquinolones with different pathogens, but their clinical significance has not yet been established. More information is needed on the role of PK/PD parameters and their magnitude for preventing mutations and the emergence of resistant organisms for most classes of antibiotics.
Naturally Occurring Monobactams

Publisher Summary The naturally occurring monobactams discovered to date are uniformly poor antibiotics that afford in themselves no opportunity for clinical utility. However, the monobactam nucleus and analogs with a variety of substituents in the 1-, 3-, and 4-positions of the azetidinone ring are readily accessible by synthesis. This highly active area of research has been the subject of recent reviews. A number of synthetic analogs that have excellent antimicrobial activity in vivo have been developed. Aztreonam, the first synthetic monobactam to undergo clinical trials, has entered the market, and a second synthetic monobactam, AMA 1080, is presently undergoing clinical trials. Both of these antimicrobial agents are useful for treating gram-negative bacterial infections by parenteral administration. An orally active prodrug, SQ 82,531, has been described and is presently undergoing clinical evaluation. This agent illustrates an alternative mode of providing activation of the β-lactam and (after enzymatic hydrolysis to SQ 82,291) an anionic binding site. Because of the great synthetic flexibility inherent in the monobactam system, it is probable that further clinically useful antimicrobial agents will follow.
An Investigation of the Organizational and Behavioral Effects of Corporate and National Culture on Budgeting Systems

We investigated the effects of corporate versus national culture by extending Hofstede et al.'s (1990) study of cross-organizational culture in a participatory budgeting environment. We surveyed Egyptian managers who worked for Egyptian or U.S. firms eliciting their perceptions of the budgeting environment. We found support for our hypotheses indicating higher (lower) levels of participation for Egyptian managers working in U.S. (Egyptian) firms, higher (lower) levels of incentive to create slack in U.S. (Egyptian) firms, and more (less) frequent slack creation behavior among Egyptian managers employed by U.S. (Egyptian) firms. Significant differences were found between levels of idealism and relativism between Egyptian subjects employed by U.S. and Egyptian companies. We also found support for our hypothesis that models of slack creation behavior will vary between U.S. and Egyptian companies employing Egyptian subjects.
Conformal field theory, two-dimensional quantum gravity and quantization of Teichmüller space

Abstract We formulate the geometric quantization of Teichmuller space by using its relation with SL(2, R ) Chern-Simons gauge theory and show that the physical state conditions arising in this formalism are equivalent to the Virasoro Ward identities satisfied by the conformal blocks in CFT. We further show that transition amplitudes between the physical states of this quantum system have a direct correspondence with covariant amplitudes of two-dimensional induced quantum gravity. Possible applications of these results to Virasoro modular geometry and (2 + 1)-dimensional quantum gravity are indicated.