cssi/SciSciGPT-SciSciNet huggingface dataset:
TOPLESS Mediates Auxin-Dependent Transcriptional Repression During Arabidopsis Embryogenesis

The transcriptional response to auxin is critical for root and vascular development during Arabidopsis embryogenesis. Auxin induces the degradation of AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors, freeing their binding partners, the AUXIN RESPONSE FACTOR (ARF) proteins, which can activate transcription of auxin response genes. We show that TOPLESS (TPL) can physically interact with IAA12/BODENLOS (IAA12/BDL) through an ETHYLENE RESPONSE FACTOR (ERF)-associated amphiphilic repression (EAR) motif. TPL can repress transcription in vivo and is required for IAA12/BDL repressive activity. In addition, tpl-1 can suppress the patterning defects of the bdl-1 mutant. Direct interaction between TPL and ARF5/MONOPTEROS, which is regulated by IAA12/BDL, results in a loss-of-function arf5/mp phenotype. These observations show that TPL is a transcriptional co-repressor and further our understanding of how auxin regulates transcription during plant development.
Quality characteristics of melting and non-melting flesh peach genotypes

A study was conducted to compare the quality characteristics of non-melting flesh (NMF) peach genotypes intended for fresh market use with the standard melting flesh (MF) peach genotypes, and to determine the effect of storage at 8 °C on the physical and chemical composition of the respective fruit types. In general, mesocarp firmness, skin L (lightness) and hue (red and orange components) decreased significantly with time in storage. This decrease was much more dramatic in MF genotypes than in their NMF counterparts. Water-soluble uronic acids increased significantly in both flesh types. Total soluble solids and total uronic acid content showed little or no change depending upon the genotype. NMF fruits had significantly higher hue and L values, firmness, soluble solids and total carotenes and xanthophylls than their MF counterparts. Water-soluble pectin content was significantly higher in MF genotypes.
Detection of the agent inside or behind a barrier material

Terahertz Time domain spectroscopy (THz -TDS ) can provide the optical response of a medium in both amplitude and phase. We show that such capability can enable a detail analysis of optical properties of RDX sample. Such study is important for standoff detection of presence of RDX sample, where a detail analysis is difficult if not possible due to a complicated system involved and multiple effects involved. We proposed a match filter method for detection of RDX inside or behind a barrier.
Biochemical Characterization of the ATPase and Helicase Activity of UAP56, an Essential Pre-mRNA Splicing and mRNA Export Factor

DEXD/H-box protein UAP56 is an essential pre-mRNA splicing factor required for the first ATP-dependent spliceosome assembly step. UAP56 is also essential for the export of the majority of mRNAs from the nucleus to the cytoplasm. We performed biochemical characterization of UAP56's ATPase and helicase activity, which is important for further understanding the role of these activities in UAP56's function. We showed that UAP56 is an RNA-stimulated ATPase that can only hydrolyze ATP. We demonstrated that UAP56 is an ATP-dependent RNA helicase that can unwind substrates with 5' or 3' overhangs or blunt ends in vitro. We showed that U2AF(65) and Aly, two proteins known to interact with UAP56, do not influence UAP56's ATPase or helicase activity. We also demonstrated that several mutants in the conserved helicase motifs I, II, and III abolish UAP56's ATPase and/or helicase activity, providing tools for future investigation of the role of UAP56's ATPase and helicase activity in spliceosome assembly and mRNA export.
Conservation of a 23-kDa human transplantation antigen in mammalian species.

A group of transplantation antigens, referred to as tum − antigens, were identified in mouse tumor cells that had been mutagenized to produce variant cells and were recognized by clonal cytolytic T lymphocytes (CTL). Alterations in these variant cells that were recognized by CTL resulted from point mutations in the genes of specific proteins. We have isolated human and bovine cDNA clones that encode the homologs of the mouse tum − antigen P198. This 23.6-kDa protein is highly basic with a predicted p I of 11.55. p23/P198 is highly conserved across mammalian species, with >94% identity (97% including conservative substitutions) among the human, bovine, and mouse deduced amino acid sequences. The nucleotide sequences of both the coding and 5′- and 3′-untranslated regions from human, bovine, and mouse are also highly conserved with >88% identity in the coding regions. Hybridization of poly(A) + RNA from various mammalian sources with cDNA and oligonucleotides specific for the coding region identified two mRNAs of 1.2 and 0.8 kb, whereas probes specific for the 3′-untranslated region between two consensus polyadenylation signals hybridized with the 1.2-kb, but not the 0.8-kb, mRNA. The abundance of the 1.2-kb mRNA relative to that of the 0.8-kb species varied depending upon the cell type. A single predominant transcription initiation site was mapped by primer extension. These studies indicate that this highly basic 23.6-kDa protein is encoded by two major mRNA species that differ only in the length of their 3′-untranslated regions and that the mechanism that gives rise to these two mRNAs, utilization of alternative polyadenylation sites, is conserved across species. Moreover, it appears that the protein product of the p23/P198 gene is under considerable evolutionary pressure to maintain its structural features.
An aftereffect to discrete stimuli producing apparent movement and succession

After observing the sequential flashing of two lights that produced either the perception of apparent movement or the perception of the succession of two stationary lights, the presentation of the lights in the opposite direction produced the perception of a more rapid apparent movement or of a more rapid succession of the light flashes. These aftereffects suggest the presence of neural structures for the discrimination of sequential changes in spatial position which are subject to adaptation and respond with decreased sensitivity to the repetitive presentation of the two lights in a given spatial direction. The results are interpreted to support the hypothesis that the perception of apparent movement involves the excitation of specific neural mechanisms selectively responsive to sequential changes in stimulus position. An alternative hypothesis is that the perception of apparent movement involves an inference based on the separate registrations of the position of a stimulus at one point in time and the position of that stimulus at an earlier point in time.
Pituitary Adenylate Cyclase-activating Polypeptide (PACAP) and Vasoactive Intestinal Peptide (VIP) Regulate Murine Neural Progenitor Cell Survival, Proliferation, and Differentiation

Neural stem/progenitor cells (NPC) have gained wide interest over the last decade from their therapeutic potential, either through transplantation or endogenous replacement, after central nervous system (CNS) disease and damage. Whereas several growth factors and cytokines have been shown to promote NPC survival, proliferation, or differentiation, the identification of other regulators will provide much needed options for NPC self-renewal or lineage development. Although previous studies have shown that pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) can regulate stem/progenitor cells, the responses appeared variable. To examine the direct roles of these peptides in NPCs, postnatal mouse NPC cultures were withdrawn from epidermal growth factor (EGF) and fibroblastic growth factor (FGF) and maintained under serum-free conditions in the presence or absence of PACAP27, PACAP38, or VIP. The NPCs expressed the PAC1(short)null receptor isoform, and the activation of these receptors decreased progenitor cell apoptosis more than 80% from TUNEL assays and facilitated proliferation more than fivefold from bromodeoxyuridine (BrdU) analyses. To evaluate cellular differentiation, replicate control and peptide-treated cultures were examined for cell fate marker protein and transcript expression. In contrast with previous work, PACAP peptides downregulated NPC differentiation, which appeared consistent with the proliferation status of the treated cells. Accordingly, these results demonstrate that PACAP signaling is trophic and can maintain NPCs in a multipotent state. With these attributes, PACAP may be able to promote endogenous NPC self-renewal in the adult CNS, which may be important for endogenous self-repair in disease and ageing processes.
Automated polyp measurement based on colon structure decomposition for CT colonography

Accurate assessment of colorectal polyp size is of great significance for early diagnosis and management of colorectal cancers. Due to the complexity of colon structure, polyps with diverse geometric characteristics grow from different landform surfaces. In this paper, we present a new colon decomposition approach for polyp measurement. We first apply an efficient maximum a posteriori expectation-maximization (MAP-EM) partial volume segmentation algorithm to achieve an effective electronic cleansing on colon. The global colon structure is then decomposed into different kinds of morphological shapes, e.g. haustral folds or haustral wall. Meanwhile, the polyp location is identified by an automatic computer aided detection algorithm. By integrating the colon structure decomposition with the computer aided detection system, a patch volume of colon polyps is extracted. Thus, polyp size assessment can be achieved by finding abnormal protrusion on a relative uniform morphological surface from the decomposed colon landform. We evaluated our method via physical phantom and clinical datasets. Experiment results demonstrate the feasibility of our method in consistently quantifying the size of polyp volume and, therefore, facilitating characterizing for clinical management.
Enhancement of transfecting activity of bacteriophage P22 DNA upon exonucleolytic erosion.

Abstract The transfecting efficiency of P22 DNA on “rough” strains of Salmonella typhimurium or non-restricting mutants of Escherichia coli K12 approaches 3 × 10−8 plaques/genome equivalent. It increases 20-fold upon complete erosion of the terminally redundant regions of the DNA molecule with either λ exonuclease or exonuclease III. Eroded DNA molecules form circles and linear oligomers upon annealing. The circular monomers display transfecting activity about ten times higher than that of eroded linear monomers or hydrogen-bonded oligomers. recB recC sbcB strains of E. coli K12 are transfected with P22 DNA with an efficiency of 1.5 × 10−6 plaques/genome equivalent. The activity of DNA molecules on these strains is not augmented by erosion. This suggests that the activation by erosion, seen in assays on rec+ genotypes, is due to the formation of hydrogen-bonded circular molecules, which more readily escape degradation by the recBC nuclease.
The structure of slow crack interfaces in silicon nitride

Fracture interfaces formed in silicon nitride at high temperatures were studied using light and electron microscopy. The structure of the fracture interface depended on the type of silicon nitride fractured. High-purity, reaction-bonded silicon nitride always formed flat, relatively featureless, fracture surfaces. Fracture occurred by a brittle mode even at the highest temperature (1500° C) studied. The critical stress intensity factor for reaction-bonded silicon nitride (∼ 2.2 MN m−3/2) is relatively low and is insensitive to temperature. By contrast, hot-pressed silicon nitride gave evidence of plastic flow during fracture at elevated temperatures. Crack growth in magnesia-doped, hot-pressed silicon nitride occurs by creep, caused by grain boundary sliding and grain separation in the vicinity of the crack tip. As a consequence of this behaviour, extensive crack branching was observed along the fracture path. The primary and secondary cracks followed intergranular paths; sometimes dislocation networks, generated by momentary crack arrest, were found in grains bordering the crack interface. As a result of the high temperature, cracks were usually filled with both amorphous and crystalline oxides that formed during the fracture studies. Electron microscopy studies of the compressive surfaces of fourpoint bend specimens gave evidence of grain deformation at high temperatures by diffusion and dislocation motion.
Bulk segregant RNA-seq reveals expression and positional candidate genes and allele-specific expression for disease resistance against enteric septicemia of catfish.

Background The application of RNA-seq has accelerated gene expression profiling and identification of gene-associated SNPs in many species. However, the integrated studies of gene expression along with SNP mapping have been lacking. Coupling of RNA-seq with bulked segregant analysis (BSA) should allow correlation of expression patterns and associated SNPs with the phenotypes.
Autonomous evolution of topographic regularities in artificial neural networks

Looking to nature as inspiration, for at least the past 25 years, researchers in the field of neuroevolution (NE) have developed evolutionary algorithms designed specifically to evolve artificial neural networks (ANNs). Yet the ANNs evolved through NE algorithms lack the distinctive characteristics of biological brains, perhaps explaining why NE is not yet a mainstream subject of neural computation. Motivated by this gap, this letter shows that when geometry is introduced to evolved ANNs through the hypercube-based neuroevolution of augmenting topologies algorithm, they begin to acquire characteristics that indeed are reminiscent of biological brains. That is, if the neurons in evolved ANNs are situated at locations in space (i.e., if they are given coordinates), then, as experiments in evolving checkers-playing ANNs in this letter show, topographic maps with symmetries and regularities can evolve spontaneously. The ability to evolve such maps is shown in this letter to provide an important advantage in generalization. In fact, the evolved maps are sufficiently informative that their analysis yields the novel insight that the geometry of the connectivity patterns of more general players is significantly smoother and more contiguous than less general ones. Thus, the results reveal a correlation between generality and smoothness in connectivity patterns. They also hint at the intriguing possibility that as NE matures as a field, its algorithms can evolve ANNs of increasing relevance to those who study neural computation in general.
SU‐FF‐T‐56: A Virtual Frame System for SRS Planning

Purpose: Stereotactic radiosurgury with the Gamma Knife (GK) (Elekta, Stockholm, Sweden) is oftentimes unnecessarily complicated by sub‐optimal placement of the stereotactic frame; in some cases, treatments must be aborted. The GK treatments are frequently prolonged by the time required for Leksell Gamma Plan (LGP) RTP. We are developing a virtual frame tool for GK SRS which will 1) provide the neurosurgeon with visual and quantitative guidance for optimal frame placement and 2) facilitate the creation of preliminary treatment plans within LGP using pre‐treatment or non‐stereotactic MR studies. Method and Materials: A Gamma Knife virtual frame (GKVF) placement system exploits the framework of the Pinnacle3 treatment planningsystem (Philips RadiationOncologySystems, Fitchburg, WI) which provides the capability to load and subsequently manipulate externally‐created triangular surface mesh objects (in VTK format) within its internal (image‐referenced) coordinate system; natively‐created or manipulated meshes can be exported in these internal coordinates. We have created, e.g, mesh representations of the Leksell frame, including the posts and fiducial indicator box. We have developed interactive Pinnacle scripts and external C++ codes to aid the user in optimizing frame placement. Results: Given a set of lesions to be treated, the GKVF software currently provides the ability to 1) interactively place a 3D mesh representation of the Leksell frame on a patient's MR study and test for clinical tenability using a fast collision detection algorithm — accessible regions for various GK modalities are indicated with computed surface meshes — and 2) “paint” virtual fiducials onto DICOM MR copies of the patient's original study based on the current virtual frame location, which, together with the GKVF system's ability to generate virtual “skull and frame” measurements, facilitates LGP dose planning on the painted image sets. Outlook: Currently under development is a quantitative mechanism to guide the neurosurgeon in actual frame placement.
Simultaneous Temperature and Species Measurements During Self-Oscillating Burning of HMX

The near-surface species and surface temperature were simultaneously measured during self-oscillatory burning of octahydro-l,3 ,5,7-tetranitro-l,3,5,7-tetrazocine (HMX). A CO2 laser was used to heat the propellant surface at atmospheric pressure in argon. A microprobe/tri ple quadrupole mass spectrometer system was used to measure species profiles, and fine-wire thermocouples were used to measure surface temperature. Oscillations of species, temperature, and burning rate were observed with an average surface temperature of —633 K and frequency of 4 ± 0.2 Hz. The mole fraction of NO2, HCN, and triazine oscillated in phase with temperature, whereas the mole fractions of N 2O, CH2O, and the species at mass 28 were 180 deg out of phase with temperature. NO2 and CH2O were the most abundant species followed by HCN, N2O, H2O, the species at mass 28, and other species. The production of NO 2 and HCN was favored with an increase in temperature and burning rate, whereas the production of N 2O and CH2O became more important with a decrease in temperature and burning rate. This was qualitatively in line with the accepted global reaction branches in the condensed phase of HMX. From these data, variations of the mole fractions of NO 2, N2O, CH2O, and HCN could be directly related to surface temperature. Analysis of the data indicates that the observed oscillatory burning might be related to multiple-step reactions in the condensed phase.
The Japanese Experience With Scarcity: Management of Traditional Common Lands

One of the first things we all learn in studying environmental problems is that environmental quality is a public or collective good and, conversely, that environmental degradation is a public or collective bad. For this reason, action by isolated individuals, however well-intentioned, cannot yield overall improvements in environmental quality and cannot prevent environmental degradation. This "public goods" or "free-rider" problem has been eloquently described in Garrett Hardin's famous essay, "The Tragedy of the Conunons," and carefully analyzed in Mancur Olson's The Logic of Collective Action.1 In essence, rational individuals acting in their own interest in the absence of any mechanism for cooperation will gradually but inexorably withhold their contributions to the maintenance of, or use up more than their fair share of, commonly held assets, eventually threatening the very existence of those collective goods. Some sort of collective decision to cooperate and exercise mutual restraint (what Hardin calls "mutual coercion mutually agreed upon") is obviously necessary. Thus environmental problems are by their very nature political. The challenge for society is to figure out how to eliminate circumstances in which rational individuals will make decisions that lead inexorably to tragedies of the commons, essentially to create greater overlap and syncrony between private good and public good. To date, economists have paid the most careful attention to free-rider problems, analyzed their characteristics, and even devised some potential theoretical solutions.2
Pulmonary Arteriovenous Malformation Embolization: How We Do It

We report our experience with an embolization technique that allows safe, controllable exclusion of pulmonary arteriovenous malformations using detachable coils, a single venous access site, coaxial catheter guidance, and 1 or 2 microcatheters. This technique is particularly useful when treating central lesions with a short feeding artery and when high flow increases the risk of coil migration and nontarget embolization. It affords precise placement and repositioning of coils prior to detachment. The technique facilitates safe and successful endovascular closure of these challenging lesions.
Gigahertz photothermal effect in silicon waveguides

We present a theoretical and experimental study of the frequency response of the photothermal effect in silicon waveguides. The effect is studied for modulation frequencies up to 3GHz using integrated photonic circuits in Mach–Zehnder and ring oscillator configurations. The thermal behavior of silicon waveguides is described by a diffusive substrate heating model. In the low-frequency regime, the frequency response follows a −log(f) dependence, while a f−1∕2 dependence is found in the high-frequency regime. Close agreement between theory and experiment allows for the accurate extraction of the photothermal absorption coefficient.
Progressive filter network: A general classification algorithm☆

Abstract Mass spectral data and EKG data have been used for the development of a Progressive Filter Network (PFN) algorithm which should be of wide utility. The PFN algorithm was compared to more sophisticated pattern recognition techniques and found to give comparable results. The advantages of the PFN algorithm are computational simplicity and the fact that the decision network generated may be used directly for feature selection.
The rating scale preference measure as an evaluative measure in systemic lupus erythematosus

Preference measures may be useful tools to assess patients' overall health-related quality of life. We studied the validity and sensitivity to change of the rating scale preference measure in patie...
Virtual Oscillator Control for voltage source inverters

This paper summarizes a suite of methods that have recently been proposed for the control and synchronization of parallel single- and three-phase voltage source power electronics inverters. Inspired by the phenomenon of synchronization in networks of coupled oscillators, the premise of the proposed Virtual Oscillator Control (VOC) is to control an inverter such that it mimics the dynamics of a nonlinear oscillator. Consequently, the inverters synchronize their voltage outputs and share the load power in proportion to their power ratings without any communication. The VOC design philosophy and sufficient conditions for global asymptotic synchronization are outlined. Simulations validate the analytical results for a parallel system of three-phase inverters serving a constant-power load.
Determinants of Adolescent Fertility and Its Consequences for Maternal Health, with Special Reference to Rural Bangladesh

The second section of this paper set forth a theoretical model relating adolescent growth and development to family formation patterns and their implications for maternal and child health. Subsequent sections of the paper examine the evidence to support specific relationships hypothesized in the model, focusing on longitudinal data from Matlab, Bangladesh. Despite the emphasis on developing country populations, literature from developed countries was also reviewed. The weight of the evidence suggests that in the developed countries, while there is a positive relationship between reproductive maturation and subsequent reproductive behavior, the negative effects of young maternal age on pregnancy outcome is confounded with socioeconomic factors. Teenage pregnancy, or at least teenage birth, occurs disproportionately among the socially and economically disadvantaged. Moreover, teenage childbearing in the U.S., especially when it occurs outside of marriage, violates social norms, at least in the white population. Poor diet may be a problem in the U.S. but it does not appear to result in notable delays in physical growth and development, delayed or compromised adolescent growth, or late age at menarche. Limited evidence suggests that early menarche may be associated with more rapid onset of mature menstrual cycle activity but these findings have not been replicated elsewhere. In developing countries the situation is quite different. First, early marriage and childbearing are desired and common across most segments of society. Second, malnutrition is widespread, and is sufficiently severe to delay the adolescent growth spurt and raise average age at menarche by two to three years compared with developed country populations. This is certainly the case in Bangladesh. In this setting, several observations regarding the relationship of nutritional status, adolescent development and reproduction have been made. First, undernutrition delays growth and reproductive maturation, and women who mature early (i.e., women with young age at menarche) marry at younger ages than later maturers. In addition, body weight appears to have an independent effect on age at marriage, net of age at menarche, such that relatively heavy women marry at younger ages than their lighter counterparts. Explanations for this finding include correlation between body weight and development of secondary sex characteristics, and perhaps a cultural perception that heavier (i.e., normal body weight) women are more attractive, or healthier, mates. The effect of menarche and nutritional status on marriage gives rise to concern that an improvement in nutritional status, and an increase in the age at menarche, would lead to younger marriage and first birth, and higher lifetime fertility.(ABSTRACT TRUNCATED AT 400 WORDS)
Incarceration During the Transition to Adulthood: A “Snapshot” of At-Risk Males at 25

Previous literature points to events during the transition to adulthood as important in understanding criminal offending over the life course. But youth in today’s inner cities are at high risk of experiencing periods of incarceration, which may compromise successful entry into adult roles. Indeed, incarceration has become so common among inner-city youth that it has been said to be a critical event during the transition to adulthood alongside transitions in education, employment, residence, marriage, and parenting. Drawing on data from the Pittsburgh Youth Study, this paper explores the place of incarceration in the transition to adulthood experiences of at-risk males. We offer a descriptive account of the relative frequency of incarceration vis-a-vis other, more traditional life events. Given the interrelationships between life events, we apply latent class cluster analysis to explore and identify typical combinations in which they occur. This allows us to present a “snapshot” of life trajectories among at-risk males at 25.
Dynamical Evidence For Dark Matter

Dark matter has been studied dynamically on all scales from the solar system to superclusters. There is much less dark matter in the disk of the Milky Way than would be needed to explain the local rotation curve, but there is evidence for considerable dark matter in a flattened distribution. Three new results are discussed regarding dark matter on galactic scales: the dark halos of spirals appear to be flattened, elliptical galaxies have dark matter halos, and the halos of ellipticals have 25% less mass than previously believed. Dark matter halos around spiral galaxies extend to 200 kpc and perhaps to 1 or 2 Mpc. Previous measurements from galaxy motions indicating that clusters have large amounts of dark matter Ω ∼ 0.2) are now confirmed by estimates derived from X-ray gas. Moreover, the measurements show that the mean speed of the galaxies and the gas particles is the same, indicating that the galaxy velocities are not ‘biased’. Measurements of dark matter on the largest scales are qualitatively different from other dark matter measurements in that they generally derive from linearly perturbed (as opposed to virialized or relaxed) motions. Preliminary estimates show Ω ∼ 0.3-1 on these scales.
Comparison of dideoxynucleoside drugs (DDI and zidovudine) and induction of hematopoietic toxicity using normal human bone marrow cells in vitro.

The drug zidovudine (AZT), a synthetic thymidine analog, has been used in the treatment of acquired immunodeficiency syndrome (AIDS). Clinical use of zidovudine has induced hematopoietic toxicity manifested by anemia, neutropenia and on occasion thrombocytopenia. Such toxicity has stimulated the development of alternative dideoxynucleoside drugs capable of exerting anti-viral potency while minimizing the risk for inducing organ toxicities. One such alternative dideoxynucleoside drug is 2',3'-dideoxyinosine (ddI). Recent therapeutic anti-viral strategy, now undergoing clinical trial, is the evaluation of combined zidovudine ddI treatment. Unfortunately a complete assessment of their potential toxicity using this drug regimen has not been thoroughly examined. We report here the results of studies comparing the toxicity profile of zidovudine versus ddI on their ability to influence several classes of hematopoietic progenitor stem cells, e.g. granulocyte--macrophage (CFU-GM), megakaryocyte (CFU-Meg) and erythroid (CFU-E/BFU-E) following in vitro co-culture with normal human bone marrow. Since the main clinical toxicity associated with zidovudine in vivo is the development of anemia, additional in vitro studies compared the dose-escalation effect of erythropoietin in the presence of combined zidovudine and ddI. CFU-GM, CFU-Meg, CFU-E and BFU-E were all reduced (P < 0.05) following incubation with either zidovudine or ddI thus determining their ID50 concentrations for these classes of hematopoietic progenitors; however, the extent of toxicity associated with ddI was lower than what was observed with zidovudine. More importantly, dose-escalation of erythropoietin was effective in reversing the inhibition observed for ddI on erythroid progenitors CFU-E and BFU-E (P < 0.05), an effect not reported with zidovudine in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)
DATA-FREE INFERENCE OF UNCERTAIN PARAMETERS IN CHEMICAL MODELS

We outline the use of a data-free inference procedure for estimation of uncertain model parameters for a chemical model of methane-air ignition. The method involves a nested pair of Markov chains, exploring both the data and parametric spaces, to discover a pooled joint posterior consistent with available information. We describe the highlights of the method, and detail its particular implementation in the system at hand. We examine the performance of the procedure, focusing on the robustness and convergence of the estimated joint parameter posterior with increasing number of data chain samples. We also comment on comparisons of this posterior with the missing reference posterior density.
Design for a near-infrared immersion echelle spectrograph: Breaking the R=100,000 barrier from 1.5 to 5 μm

We have designed a near IR spectrograph, sensitive in the 1.5-5 micrometers range, that uses a silicon immersion echelle grating. The cross-dispersed design demonstrates that immersion echelles allow compact spectrographs which have excellent spectral coverage and very high resolving power. Our instrument will have continuous spectral coverage over a 5.7 percent passband at 2.3 micrometers or a 7.6 percent passband at 4.6 micrometers and resolving power ranging from R equals 87,000 at 4.6 micrometers to 109,000 at 2.3 micrometers . We discuss design issues that are unique to spectrographs using silicon immersion echelle gratings in the near IR such as grating parameters, geometry, and the mechanical and thermal properties of large pieces of single crystal silicon.
Coordinate regulation of gluconeogenesis by the glucocorticoids and glucagon: evidence for acute and chronic regulation by glucagon.

The coordinate regulation of gluconeogenesis by the glucocorticoids and glucagon in primary cultures of adult rat liver parenchymal cells has been studied. The results suggest that glucagon stimulation of glucose production from 3-carbon precursors is composed of at least two components which the glucocorticoids differentially affect. Glucagon treatment of hepatocytes results in an immediate increase in glucose production which is not blocked by cycloheximide and occurs in the absence of any detectable increase of phosphoenolpyruvate carboxykinase activity. This component appears to be regulated by a post-translational mechanism and involves redirection of carbon flow from glycolysis to gluconeogenesis. The second component is characterized by the need for long-term glucagon treatment. This increase in glucose production can be blocked by cycloheximide and is correlated with an increase in phosphoenolpyruvate carbooxykinase activity. The reaction that is accelerated by long-term glucagon incubation is located prior to the triose-phosphate level since long-term incubation with glucagon fails to increase glucose production from dihydroxyacetone any more than does short-term incubation. It is suggested that phosphoenolpyruvate carboxykinase rather than amino acid transport is the key pacemaker reaction in the long-term incubation since the direction and magnitude of the response for glucocorticoid and glucagon stimulation of glucose production is the same whether alanine or lactate is used as the 3-carbon precursor. The glucocorticoids exhibit an additive effect on glucagon-stimulated glucose production for the first component whereas they amplify the second component.
A genetic algorithm for optimized reconstruction of quantized one-dimensional signals

This paper describes a genetic algorithm (GA) that evolves optimized sets of coefficients for one-dimensional signal reconstruction under lossy conditions due to quantization. Beginning with a population of mutated copies of the set of coefficients describing a standard wavelet inverse transform, the genetic algorithm evolves a new set of coefficients that significantly reduces mean squared error (relative to the performance of the selected wavelet) for various classes of one-dimensional signals.
Biological role of glutathione in nitric oxide-induced toxicity in cell culture and animal models.

Abstract Glutathione (GSH) plays an important role in cellular defense response in many in vitro and in vivo models. Here we investigated its role in NO -induced toxicity in cell culture and mouse models. Wild-type (TK6) and p53-null (NH32) human lymphoblastoid cells were treated with NO at a steady-state concentration of 0.6 μM, similar to the level estimated to occur in inflamed tissues. In both cell types, GSH was depleted by this exposure in a dose- and time-dependent manner. Contrary to expectations, prior depletion of GSH by treatment with l -buthionine- SR -sulfoximine did not potentiate NO -induced cell killing or DNA deamination in TK6 cells. In activated RAW264.7 murine macrophages producing NO , intracellular GSH content did not change, although γ-glutamate-cysteine ligase was upregulated. NO overproduction in RcsX lymphoma-bearing SJL mice resulted in significantly elevated GSH levels in various organs. Administration of the NO synthase inhibitor N -methylarginine abolished the increase in GSH in these animals. Collectively, these data indicate a multifaceted and complex involvement of GSH in responses of cells and tissues to toxic levels of NO . NO treatment effectively depleted GSH levels in human lymphoblastoid cells, but this alteration was not a critical initiating factor for NO -mediated toxicity. Murine macrophages maintained GSH homeostasis when exposed to endogenously produced NO . In RcsX lymphoma-bearing mice, upregulation of de novo synthesis of GSH appeared to be a response to the toxic effects of NO .
Serum Prolactin and Growth Hormone Responses to Thyrotropin Releasing Hormone in Postpubertal Cattle

Abstract Serum prolactin increased 9 to 20 and growth hormone 2.5 to 4 times following administration of thyrotropin releasing hormone in 6 heifers during an estrous cycle, in 26 heifers during pregnancy, and in 16 cows during lactation. Stage of the estrous cycle or pregnancy did not affect quantity of prolactin or growth hormone released after administration of thyrotropin releasing hormone. There was a tendency for the quantity of prolactin released by thyrotropin releasing hormone to be greater at 2 mo than at 4, 6, 8, or 10 mo of lactation. During lactation, growth hormone release after thyrotropin releasing hormone was greatest at 2 mo. Prolactin release after thyrotropin releasing hormone was 6 to 16 times greater in summer than in spring or fall in pregnant heifers and approximately 3 times greater in spring, summer, and fall than during the winter in lactating cows. Season did not affect release of growth hormone after thyrotropin releasing hormone. Season of year more importantly affects capacity of the anterior pituitary to release prolactin than stages of the estrous cycle, pregnancy, or lactation. On the other hand, season does not affect induced release of growth hormone by thyrotropin releasing hormone. There is, however, an increased capacity of the anterior pituitary to release growth hormone during early lactation, coincident with maximal milk yield.
Detecting moving objects in an optic flow field using direction- and speed-tuned operators.

Abstract An observer moving through a scene must be able to identify moving objects. Psychophysical results have shown that people can identify moving objects based on the speed or direction of their movement relative to the optic flow field generated by the observer’s motion. Here we show that a model that uses speed- and direction-tuned units, whose responses are based on the response properties of cells in the primate visual cortex, can successfully identify the borders of moving objects in a scene through which an observer is moving.
Role of Food Prepared Away from Home in the American Diet, 1977-78 versus 1994-96: Changes and Consequences

Abstract Objective To examine changes, between 1977-78 and 1994-96, in the quantity and quality of food Americans consumed that was prepared at home versus away from home. Design Data were obtained from nationwide surveys of food consumption conducted by the US Department of Agriculture (USDA) in 1977-78 and 1994-96. To maximize comparability, we used “day 1” dietary data, which both surveys collected via 24-hour recall. Subjects/Settings Individuals 2 years of age and over were selected. USDA sampling weights were used to generate nationally representative estimates. Variables Measured We categorized foods by preparation at home or at restaurants, fast-food establishments, schools/day care, and other non-home locations. We assessed percent calories from total fat and saturated fat, and the cholesterol, sodium, fiber, calcium, and iron densities of foods prepared at home versus those prepared away from home. Statistical Analyses T tests were calculated using accepted procedures to adjust for survey design effects. Results Between 1977-78 and 1994-96, consumption of food prepared away from home increased from 18% to 32% of total calories. Meals and snacks based on food prepared away from home contained more calories per eating occasion, and “away” food was higher in total fat and saturated fat on a per-calorie basis than at-home food. “Away” food contained less dietary fiber, calcium, and iron on a per-calorie basis. Among adults but not children, food prepared away from home was more sodium and cholesterol dense. Implications When developing intervention messages and strategies, nutrition educators need to be aware of the increasing role of “away” food in Americans' diets.
Outerbridge-Kashiwagi's method for arthroplasty of osteoarthritis of the elbow — 44 elbows followed for 8–16 years

Primary osteoarthritis of the elbow is usually caused by repetitive and hard usage of the arm. In the early stage, the growing osteophytes in the olecranon, olecranon fossa, coronoid, and coronoid fossa cause pain and impair the function of the elbow. Outerbridge-Kashiwagi's method (OKM) is a simple and palliative, but not radical, arthroplasty procedure for osteoarthritis of the elbow. Forty-four elbows were reviwed at a mean follow up of 10 years 7 months (range of follow-up period, 8–16 years 4 months). Twenty-seven elbows had good relief of pain. Elbow extension had improved by an average of 6° and elbow flexion by 11°. However, it was shown that osteoarthritic changes progressed for more than 10 years after OKM.
Bilateral nictitating membrane conditioning in rabbits under asymmetrical levels of cutaneous afferent activity.

Abstract The effect of asymmetrical levels of cutaneous afferent activity (CAA) on the performance of a bilaterally conditioned nictitating membrane response in New Zealand albino rabbits was investigated. Afferent activity levels were controlled by varying US locus, corneal applications of a local anesthetic (0.5% tetracaine hydrochloride) and by exerting mechanical tension on the eyelids. Performance of the response in each eye was controlled independently of the response levels concurrently attained by the contralateral eye. Appropriate tests suggested that the two eyes do not function independently in learning, regardless of the disparity in CAA level between them, due to central transfer.
Photosensitive phosphoproteins in Halobacteria: regulatory coupling of transmembrane proton flux and protein dephosphorylation.

A photoregulated reversible protein phosphorylation system controlled by the halobacterial rhodopsins was recently reported. The results presented in this paper identify the initial steps in the pathway from the absorption of light to the photoregulated protein phosphorylation and dephosphorylation reactions. Action spectrum, biochemical, and genetic analyses show that the proton pump bacteriorhodopsin mediates light-induced dephosphorylation of three photoregulated phosphoproteins. Light absorbed by bacteriorhodopsin is used to establish a proton efflux from the cells. The increase in the inwardly directed protonmotive force (pmf) from this efflux induces dephosphorylation of the three phosphoproteins, as demonstrated by the effects of the protonophore CCCP and of artificially imposed transmembrane pH gradients. Upon darkening the cells, cessation of the proton efflux through bacteriorhodopsin causes a decrease in pmf, which induces rephosphorylation of the proteins. Pmf appears to function as a regulator rather than a driving force in this system. Measurements of pmf-driven ATP synthesis in our conditions indicate the regulation of protein phosphorylation by pmf is probably not a consequence of proton flux through the H+ ATPase, a known energy coupling structure in these cells. The properties of this system may indicate the existence of a pmf detector which regulates kinase or phosphatase activity; i.e., a regulatory coupling device.
Low friction, elastomer-containing copolyimides

Novel copoly(imide butadiene)s and copoly(imide butadiene acrylonitrile)s were synthesized from amine-terminated butadiene oligomers, amine-terminated butadiene acrylonitrile oligomers, and aromatic dianhydrides and diamines. The copoly(amide acid)s were synthesized in a mixture of N-methyl-2-pyrrolidinone and toluene and were subsequently cast into thin films. The films were cyclodehydrated under a nitrogen atmosphere with a final cure at 250°C to minimize thermal degradation of the aliphatic components. Free-standing films of the copolymers exhibited reduced optical transparency, mechanical properties, water contact angle values, and sliding coefficients of friction when compared with homopolyimide films. These results indicated both bulk and surface phase segregation. Surface phase segregation was observed using atomic force microscopic imaging and was related to insufficient elastomer wetting of the casting surface. The detailed results of this study are discussed herein.
Asynchronous Logic Design

The sections in this article are 1 Fundamentals and Motivation 2 Asynchronous Logic 3 Asynchronous Design Methodologies 4 Asynchronous Processors and other Design Examples 5 Conclusions
A Sensitized Genetic Screen to Identify Novel Regulators and Components of the Drosophila Janus Kinase/Signal Transducer and Activator of Transcription Pathway

The JAK/STAT pathway exerts pleiotropic effects on a wide range of developmental processes in Drosophila. Four key components have been identified: Unpaired, a secreted ligand; Domeless, a cytokine-like receptor; Hopscotch, a JAK kinase; and Stat92E, a STAT transcription factor. The identification of additional components and regulators of this pathway remains an important issue. To this end, we have generated a transgenic line where we misexpress the upd ligand in the developing Drosophila eye. GMR-upd transgenic animals have dramatically enlarged eye-imaginal discs and compound eyes that are normally patterned. We demonstrate that the enlarged-eye phenotype is a result of an increase in cell number, and not cell volume, and arises from additional mitoses in larval eye discs. Thus, the GMR-upd line represents a system in which the proliferation and differentiation of eye precursor cells are separable. Removal of one copy of stat92E substantially reduces the enlarged-eye phenotype. We performed an F1 deficiency screen to identify dominant modifiers of the GMR-upd phenotype. We have identified 9 regions that enhance this eye phenotype and two specific enhancers: C-terminal binding protein and Daughters against dpp. We also identified 20 regions that suppress GMR-upd and 13 specific suppressors: zeste-white 13, pineapple eye, Dichaete, histone 2A variant, headcase, plexus, kohtalo, crumbs, hedgehog, decapentaplegic, thickveins, saxophone, and Mothers against dpp.
Short-term tracheal occlusion in fetal lambs with diaphragmatic hernia improves lung function, even in the absence of lung growth

Abstract Background/Purpose: Prolonged tracheal occlusion (TO) accelerates lung growth but impairs surfactant production. Short-term TO results in less lung growth but preserves type II cell function. The authors studied the effects of short-term TO on lung physiology in diaphragmatic hernia. Methods: Diaphragmatic hernia was created in 9 fetal lambs at 90 to 95 days. Five were left uncorrected (CDH), 4 underwent 2-week TO (108 to 122 days; CDH + TO). Five unoperated lambs served as controls. Near-term (136 days) fetuses were ventilated for 90 to 150 minutes. Pulmonary arterial pressure, postductal blood gases, quasistatic compliance, total lung capacity (TLC), and lung weight to body weight (LW/BW) were measured. Results: There was an overall survival rate of 89% at full term. Short-term occlusion did not induce lung growth (TLC and LW/BW, 6.07 ± 2.92 mL/kg and 0.022 ± 0.008 in CDH, 4.86 mL/kg and 0.019 ± 0.005 in CDH + TO, 10.81 ± 3.55 mL/kg and 0.036 ± 0.006 in controls, respectively). However, pulmonary hypertension in CDH (47.4 ± 12.32/35.8 ± 12.19 torr) was corrected by short-term occlusion (20.2 ± 4.0/16.0 ± 4.8 torr in CDH + TO, P 2 and p CO 2 improved after occlusion (CDH, 48.6 ± 6.7 torr and 107.1 ± 34.3 torr, respectively; CDH + TO, 101.5 ± 16.3 torr and 81.9 ± 2.4 torr; control, 291.4 ± 4.7 torr and 37.7 ± 17.3), as did oxygenation index ( P v CDH + TO; CDH, 97.2 ± 23.0; CDH + TO, 28.7 ± 3.1; control, 5.6 ± 0.6). Conclusions: Short-term TO corrects pulmonary hypertension and improves gas exchange in fetal lambs with diaphragmatic hernia despite failure to produce accelerated lung growth. Inducing lung maturation and correcting the physiological derangement in diaphragmatic hernia may be more important than achieving lung growth alone. J Pediatr Surg 35:775-779. Copyright © 2000 by W.B. Saunders Company.