cssi/SciSciGPT-SciSciNet huggingface dataset:
Some properties of silkmoth moulting gel and moulting fluid

Abstract The moulting fluid of silkmoths contains numerous proteins, mostly in the range of 20,000 to 70,000 molecular weight. Only a fraction of these proteins have known enzymatic activity. Approximately ten bands are resolved by polyacrylamide disk gel electrophoresis. The moulting fluid is a distinct secretion differing from blood in almost every parameter studied: pH, visible absorption spectrum, protein content, enzymatic activities, and protein electrophoretograms; the u.v. spectrum and possibly the electrophoretic mobilities of a few proteins are similar in blood and fluid. Proteolytic activity appears in the moulting fluid at the beginning of the last week of the pharate adult stage (on day 12 of adult development in Antheraea polyphemus) and shows a time-activity profile that correlates well with the rate of digestion of pupal endocuticle. By contrast, general esterases of moulting fluid show a relatively constant level of activity. As adult development proceeds, the fluid becomes enriched in dialysable components. Endocuticle digestion was studied in vivo and in vitro. The amount of proteinase in moulting fluid (ca. 9 μg trypsin equivalents in 150 μl, less than 1% of the total protein) is consistent with the quantity of protein in the pupal endocuticle (ca. 85 mg) and the period of time (2–4 days) required for full digestion in vivo.
DC fibre-optic accelerometer with sub-μg sensitivity

We describe a fibre-optic accelerometer, based on the technique of nonlinear displacement-to-strain conversion (NDSC), suitable for use at DC and low frequencies. The sensor exhibits a minimum detectable acceleration of less than 1 μg RMS (g = 9.8 m/s 2 ) at 0.5 Hz and a linear dynamic range greater than 10 6 .
On renamable Horn and generalized Horn functions

A Boolean function in disjunctive normal form (DNF) is aHorn function if each of its elementary conjunctions involves at most one complemented variable. Ageneralized Horn function is constructed from a Horn function by disjuncting a nested set of complemented variables to it. The satisfiability problem is solvable in polynomial time for both Horn and generalized Horn functions. A Boolean function in DNF is said to berenamable Horn if it is Horn after complementation of some variables. Succinct mathematical characterizations and linear-time algorithms for recognizing renamable Horn and generalized Horn functions are given in this paper. The algorithm for recognizing renamable Horn functions gives a new method to test 2-SAT. Some computational results are also given.
Survival in subpopulations of cells derived from solid KHT sarcomas by centrifugal elutriation following treatment with CCNU and MISO.

Abstract Misonidazole (MISO) has been shown to enhance the cytotoxicity of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) in a number of different animal tumor systems. We have investigated the response to therapy of the various subpopulations of cells comprising the KHT sarcoma, to determine whether chemopotentiation occurred as a preferential enhancement of killing in one subpopulation of cells. Twenty-four hr after drug treatment, cells dissociated from solid tumors were separated into homogeneous populations based on cell size by the technique of centrifugal elutriation. By this method the majority of the non-neoplastic cells could be removed and the tumor cells separated into fractions containing 90 to 95% G 1 cells, 70 to 75% S cells and 70 to 80% G 2 M cells. Clonogenic cell survival was measured for each elutriated fraction. In vivo treatment with 0.5 mg/g MISO produced no measurable cell-kill across the cell cycle. Those cells in late G, and S phase 24 hr after treatment were most sensitive to CCNU alone. The enhancement of CCNU cytotoxicity by MISO occurred primarily in the early G 1 and S fractions. These data suggest that chemopotentiation does not occur equally in all tumor cell subpopulations and that some specificity of enhanced cell killing exists
Regional age-related effects in the monkey brain measured with 1H magnetic resonance spectroscopy.

The rhesus monkey is a useful model for examining age-related effects on the brain, because of the extensive neuroanatomical homology between the monkey and the human brain, the tight control for neurological diseases as well as the possibility of obtaining relevant behavioral data and post-mortem tissue for histological analyses. Here, proton magnetic resonance spectroscopy ( 1 H-MRS) was used together with high-resolution anatomical MRI images to carefully assess regional concentrations of brain metabolites in a group of 20 rhesus monkeys. In an anterior volume of interest (VOI) that covered frontal and prefrontal areas, significant positive correlations of myo-inositol and of total creatine concentrations with age were detected, whereas N-acetyl aspartate (NAA) and choline compounds (Cho) were not significantly correlated with age. In an occipito-parietal VOI, all metabolites showed no statistically significant age-dependent trend. Strong correlations were found between NAA concentration and gray matter fraction in the VOIs as well as between choline compounds and white matter fraction.
City-Suburb Differences in African American Male Labor Market Achievement

This research tests the spatial mismatch hypothesis by comparing the employment probabilities of central city versus suburban African American males in nine metropolitan areas. Treatment effects models are used to control for the effects of both individual characteristics and residential self-selection on the probability of employment. A positive effect of suburban residential location on employment is found for the residents of Dallas, Los Angeles, New York, and Washington, while no effect is found for the residents of Cleveland, Houston. Jackson, Memphis, and Newark. The general conclusion to be drawn is that the spatial mismatch effect is contingent on the particular characteristics of each metropolitan area. Preliminary analysis shows that metropolitan areas with a spatial mismatch effect are large in terms of total population and total land area, and have less efficient transportation systems.
Angiogenesis and microvascular remodeling: a brief history and future roadmap.

Angiogenesis and vessel remodeling determine the integrative control of the architectural structure and functional behaviors of the microcirculation over the lifetime of an organism. Vascular remodeling is the basis of promising therapeutic strategies, including vascularization of ischemic organs. The history of angiogenesis research is long—more than 250 years—and the Microcirculatory Society has been the birthplace of numerous techniques, assays, and scientific concepts that have stimulated massive research endeavors in the pharmaceutical and medical arena. At present, angiogenesis is a dynamic field in which the molecular genetic and proteomic components of the process are still being identified, while integrative systems approaches are once again being recognized as essential to understand microvascular assembly in vivo across multiple scales from cells to whole vessel networks. A short history of people and ideas in this field is presented, followed by discussion of emerging directions receiving intense attention today and major questions that remain unanswered. The primary conclusion is that the need for scientists trained in the integrative approaches nurtured by the Microcirculatory Society over the past 50 years has never been greater, as it is clear that a complete mechanistic understanding of vessel adaptation (based on genomic and proteomic supporting casts) will now require deeper studies of angiogenesis and microvascular remodeling in the exquisite complexity of the native microenvironment—the microcirculation.
Synthesis of 2-acetamido-2-deoxy-3-O-β-L-fucopyranosyl-D-glucose

Abstract Crystalline 2-acetamido-2-deoxy-3-O-β- L -fucopyranosyl- D -glucose was synthesized by condensation of 2,3,4-tri-O-acetyl-α- L -fucopyranosyl bromide with benzyl 2-acetamido-4,6-O-benzylidene-2-deoxy-β- D -glucopyranoside, followed by removal of the protecting groups.
Expression of migration-related genes is progressively upregulated in murine Lineage - Sca-1 + c-Kit + population from the fetal to adult stages of development

Hematopoietic stem cells (HSCs) follow a genetically programmed pattern of migration during development. Extracellular matrix and adhesion molecules, as well as chemokines and their receptors, are important in adult HSC migration. However, little is known about the role these molecules play at earlier developmental stages. We have analyzed by quantitative polymerase chain reaction (qPCR) array the expression pattern of extracellular matrix and adhesion molecules as well as chemokines and chemokine receptors in Lineage-Sca-1+c-Kit+ (LSK) cells at different stages of development, in order to characterize the role played by these molecules in LSK. Data were represented by volcano plots to show the differences in expression pattern at the time points studied. Our results show marked changes in the expression pattern of extracellular matrix, adhesion molecules, chemokines and their receptors with developmental age, particularly in later stages of development. Ten molecules were significantly increased among the LSK populations studied. Our screen identified the upregulation of Col4a1, as well as molecules involved in its degradation (Mmp2, Timp2), with development. Other genes identified were Sell, Tgfbi, and Entpd1. Furthermore, we show that the expression of the chemokines Ccl4, Ccl9, Il18 and the chemokine receptor Cxcr4 increases in LSK cells during development. Several genes are upregulated in the LSK population in their transition to the bone marrow microenvironment, increasing at later stages of development. This gene pattern should be emulated by embryonic stem cell-derived hematopoietic progenitors in order to improve their properties for clinical applications such as engraftment.
Localization of receptors for luteinizing hormone-releasing hormone in pancreatic and mammary cancer cells.

Abstract Previous work showed that hamster and human pancreatic tumors but not normal pancreata exhibit low-affinity cell-membrane receptors for luteinizing hormone-releasing hormone (LHRH). Although the regression of experimental pancreatic cancers induced by treatment with LHRH agonists or antagonists could be explained in part by the creation of sex-steroid deficiency, direct effects mediated by LHRH receptors might also play a role. Here, we demonstrate that pancreatic tumor cells do exhibit high-affinity binding sites for LHRH, but only in their nuclei; low-affinity sites are associated with the cell membranes. These binding sites appear to be LHRH receptors since electron microscopic immunohistochemical studies show that an antibody to the LHRH receptor reacted with sites in the nucleus of pancreatic tumor cells. Immunoreactive sites in the nucleus also were found in a restricted set of normal hamster pituitary cells thought to be luteinizing hormone-secreting cells and in MXT mouse mammary tumor cells. Such nuclear receptors may be involved in the transmission of the direct action of LHRH analogues on the tumor cells, resulting in the enhancement of programmed cell death.
Sociolinguistic variation in French computer-mediated communication: A variable rule analysis of the negative particle ne

The analysis in the present study examines the variable use of ne in 2,459 tokens of verbal negation from a corpus of electronic French discourse including moderated chat, non-moderated chat, and discussion fora. These data from computer-mediated communication (CMC) environments were analyzed in order to demonstrate that although both non-moderated and moderated chat are essentially synchronous (i.e. involving real-time interaction), they are on opposite ends of a continuum of French sociolinguistic variation. In non-moderated chat, which is clearly less formal, ne is used productively as a discursive-pragmatic marker. However, in moderated chat, which resembles more formal written French discourse, ne deletion rarely occurs. Although discussion fora are somewhere between the two types of chat on the continuum of sociolinguistic variation, there is a clear tendency for them to be slightly closer to the formal/written side, yet this mode of CMC displays the greatest amount of mode-internal variation.
THE EFFECT OF COPPER DEFICIENCY ON THE NITROGEN METABOLISM AND OIL SYNTHESIS OF THE TUNG TREE.

A recent review (6) indicates that most of the literature on copper deficiency in plants is concerned with its occurrence and correction under field conditions. Only a few studies are cited as evidence of essentiality of copper in nutrient culture because of the experimental difficulties involved. This element, however, is now regarded as essential to plant growth, though its specific physiological r?le has not been determined. Recently Bailey and McHargue (5), comparing the enzymatic activities of copper-deficient and normal tomato plants, found that the only exceptional enzyme activity that could be correlated with increasing increments of copper was that of pyrogallal oxidase. Arnon (1) has found that copper is beneficial in promoting the growth of barley in non-aerated solutions, but his data do not show the definite r?le of copper in the metabolism of the plant. An interesting suggestion has been offered by Camp and Fudge (8) that in citrus the relationship between nitrogen and copper may be so important that the symptoms may more properly be regarded as a consequence of an unbalanced copper-nitrogen ratio than of copper deficiency alone. Recently, a disorder of tung trees (Aleurites fordii Hemsl.) has been described by Drosdoff and Dickey (11). They corrected the disorder by the application of copper sulphate to the soil around the tree or to the leaves as a spray. They found that in July normal trees had, on a dry-weight basis, 5 or more p.p.m. of copper in the midshoot leaves, whereas similarly located leaves on severely affected trees had only 2 to 3 p.p.m. of copper. The occurrence of this disorder in a commercial orchard of bearing 8-yearold trees near Morriston, Florida, provided material for a study of its effect on the seasonal content of reserve food material in the leaves and the synthesis of oil and other reserves in the fruit.
Combinatorial approaches to materials science

Abstract Combinatorial methods, by which large collections or libraries of compounds are synthesized and screened for a particular physical or chemical property, are being applied to inorganic and organic materials including superconductors, phosphors, ferroelectric materials, polymers and catalysts. This technology promises to significantly increase both the efficiency of the materials discovery and optimization process, as well as our information base relating to materials properties.
Hydrothermal and solid state synthesis of sodium zirconium silicophosphates

Abstract Nasicon has been prepared hydrothermally from zirconium phosphate, Zr(HPO 4 ) 2 ·H 2 O, and Na 4 SiO 4 in excess NaOH at 300°C. If the excess NaOH is omitted a pre-cursor phase forms which on heating to 1200°C yiels Nasicon. In its hydrated form Nasicon is hexagonal but on dehydration reverts to monoclinic. The triphosphate, NaZr 2 ((PO 4 ) 3 , is part of a solid solution system, Na 1+4x Zr 2−x (PO 4 ) 3 with 1 > x > 0.12. This implies that the sodium zirconium silicophosphates may also exist in zirconium deficient form.
Regulatory justice: A re-examination of the influence of class position on the punishment of white-collar crime

The issue of class bias in response to white-collar crime offenders remains unresolved because of data limitations, research design problems, and debates over the conceptualization of core factors. One problem is that previous research failed to consider the full range of legal actions that can be taken against a violator of regulatory law; it typically focuses only on criminal sanctioning when addressing the issue of bias. Recent data on formal actions taken against federal securities offenders were used to reconsider the issue of bias. This analysis, however, examined the entire range of legal actions taken against offenders—civil, administrative, and criminal. I used a logistic regression analysis to determine the sampled offenders' likelihood of receiving a punitive sanction. Both principals and “contrepreneurs” were significantly less likely to receive a punitive response than managers and other legitimate actors in the workplace. Securities professionals (other than principals) were particularly vul...
Effect of Steel-Concrete Interface on Reinforcement Corrosion in Marine Environment

This paper dealt with the influence of the steel-concrete interface quality and environmental conditions on reinforcement corrosion. High size concrete members were cast to get different interface quality decreased with the height of rebar due to the top-bar effect. Five groups of specimen with two concrete covers have subjected to different exposed programs. The experimental results showed that the concrete cover significantly influenced corrosion initiation and corrosion rate by blocking the penetration of aggressive agents. The height of rebar affected the corrosion initiation because of the variation of concrete porosity, interface defects and chloride threshold. The existence of defects at the interface was more important than the size of defect for corrosion initiation.
Gamma knife surgery for trigeminal neuralgia: Outcome, imaging, and brainstem correlates

Abstract Purpose To review our results with gamma knife surgery (GKS) in the treatment of trigeminal neuralgia (TN), and to determine whether pain relief, medication usage, and the development of facial numbness are affected by trigeminal nerve compression, MRI imaging quality, or brainstem radiation dose. Methods and materials One hundred twelve patients with TN refractory to medical or surgical management were treated at the University of Maryland Gamma Knife Center between June 1996 and July 2001. Patients were treated using a 4-mm shot to the trigeminal nerve, at a point 2–4 mm anterior to the root entry zone of the nerve into the pons. The median dose prescribed was 75 Gy (range, 60–80 Gy). T1- and T2-weighted, axial, 1.5-mm-thick MRI images were obtained using three-dimensional gradient echo acquisition after contrast injection for treatment planning. MRI images were evaluated for imaging quality (i.e., the adequacy of visualization of the affected prepontine trigeminal nerve), the presence of trigeminal nerve compression, and the brainstem dose. Follow-up data were obtained via telephone interviews, and patients were asked to rate their pre-GKS and post-GKS pain using the Barrow Neurological Institute (BNI) Pain Intensity Scale. Patients were also asked about side effects from GKS and were asked to rate any facial numbness on the BNI Facial Numbness Scale. Medication use, time to pain response, and duration of relief were also evaluated. Results Ninety-six patients who had follow-up data were included in the analysis. Eighty-six patients (89.6%) responded to GKS with an improvement in BNI pain class. Ten patients (10.4%) were found to have an MRI of poor quality, 30 (31.3%) fair quality, and 56 (58.3%) good quality. Forty-two (43.8%) received 10% of the maximal dose to the brainstem edge, whereas 54 (56.2%) received 20%. Eleven (11.5%) patients were found to have obvious nerve compression by MRI. Imaging quality ( p = 0.1863), presence of compression ( p = 0.1147), and brainstem dose ( p = 0.3168) did not correlate with treatment response. There was also no correlation between these variables (MRI quality, compression, and brainstem dose) and medication use ( p = 0.5372, p = 0.0913, p = 0.6832, respectively). Facial numbness was the only side effect experienced. Thirteen patients reported varying degrees of facial numbness, but there was no correlation between imaging quality ( p = 0.0600), brainstem dose ( p = 0.6773), and presence of compression ( p = 0.5785) with the development of facial numbness. Conclusions Gamma knife surgery is effective in the treatment of TN and has a favorable side effect profile. Treatment response and the development of facial numbness do not correlate with MRI imaging quality, presence of nerve compression, or radiation dose to the brainstem.
Mechanism of Action of β-Hairpin Antimicrobial Peptides

Previous work showed that the β-hairpin antimicrobial peptide (AMP) protegrin forms stable octameric β-barrels and tetrameric arcs (half barrels) in both implicit and explicit membranes. Here, we extend this investigation to several AMPs of similar structure: tachyplesin, androctonin, polyphemusin, gomesin, and the retrocyclin θ-defensin. We also examine synthetic β-sheet peptides selected from a combinatorial library for their ability or inability to form pores in lipid membranes. When heptameric, octameric, and decameric β-barrels and tetrameric arcs of these peptides were initially embedded in preformed neutral and anionic lipid pores, a variety of behaviors and membrane binding energies were observed. The synthetic peptides bound very strongly and formed stable barrels and arcs in both neutral and anionic pores. The natural AMPs exhibited unfavorable or marginally favorable binding energy and kinetic stability in neutral pores, consistent with the lower hemolytic activity of some of them compared with protegrin. Binding to anionic pores was more favorable, but significant distortions of the barrel or arc structures were sometimes noted. These results are discussed in light of the available experimental data. The diversity of behaviors obtained makes it unlikely that the barrel and arc mechanisms are valid for the entire family of β-hairpin AMPs.
Hemodynamic and metabolic correlates of dipyridamole-induced myocardial thallium-201 perfusion abnormalities in multivessel coronary artery disease

Abstract The mechanisms responsible for the development of reversible thallium-201 (Tl-201) defects with dipyridamole stress in patients with coronary artery disease (CAD) is not well understood. Previous experimental animal studies have demonstrated coronary steal characterized by an absolute decrease in subendocardial flow distal to a stenosis in response to dipyridamole infusion. Accordingly, the purpose of this study was to determine if reversible Tl-201 defects in response to dipyridamole infusion are reflective of myocardial ischemia or secondary to regional differences in flow reserve. Dipyridamole (0.56 mg/kg) Tl-201 imaging was performed in 23 patients in whom serial electrocardiographic, hemodynamic, aortic and coronary sinus lactate, and coronary sinus adenosine measurements were obtained. All patients with CAD had Tl-201 redistribution (3.8 ± 2.0 defects/patient), and all patients without CAD had normal scans. Mean aortic pressure was similar in both groups and did not change in response to dipyridamole (non-CAD 103 ± 11 vs CAD 99 ± 15 mm Hg, p = NS). Pulmonary capillary wedge pressure was similar at baseline (non-CAD 11 ± 4 vs CAD 13 ± 5 mm Hg, p = NS) and did not change in response to the drug (non-CAD 14 ± 3 vs CAD 15 ± 7 mm Hg, p = NS). Lactate extraction fraction was similar at baseline (non-CAD 0.22 ± 0.09 vs CAD 0.17 ± 0.14, p = NS) and decreased similarly in both groups (non-CAD 0.08 ± 0.06 vs CAD 0.05 ± 0.12, p = NS). Coronary sinus adenosine concentration was significantly higher at baseline in patients with CAD (non-CAD 16 ± 4 vs CAD 35 ± 13 ng/ml, p = 0.034), presumably to maintain resting coronary blood flow, and increased significantly with a comparable percent increase in both groups after dipyridamole (non-CAD 35 ± 10 vs CAD 69 ± 35 ng/ml, p = 0.0001). In this group of patients with multivessel CAD, dipyridamole-induced Tl-201 perfusion abnormalities were not associated with significant myocardial ischemia by hemodynamic and metabolic criteria and appeared to be more indicative of abnormal flow reserve.
Structural evolution of triniobium carbide clusters: evidence of large Cn chains (n = 3-4) in Nb3Cn- (n = 5-10) clusters.

First-principle density functional calculations and photoelectron spectroscopy experiments show that triniobium carbide clusters exist in multiple motifs. The Nb3Cn− (n = 5−10) series have isomers surrounding a triangular Nb3 base while incorporating Nb−C bonding. We provide evidence of not only C2 carbon chains but also stable isomers with previously unidentified C3 and C4 carbon chains in triniobium carbide clusters.
Monitoring of degradation of thermally aged nylon 6,6. II. Pyrolysis–gas chromatography

Pyrolysis–gas chromatography was used as an analytical method to evaluated the extent of chemical changes that occur in aged yarns and to demonstrate any correlation between measured physical properties and pyrolysis products. Nylon 6,6 yarn samples (2.5–3.0 mg) that were control-degraded as a function of humidity, temperature, and time were pyrolyzed at 500°C and chromatographed on a Graphpac AT-1000 column. The peak heights of pyrolysis products unique to the degraded material were correlated with measured tensile strength loss (−5 to −75%) of the yarns. Linear relationships were found for several of the products, one of which was identified as caprolactam. Significant changes in the pyrograms were observed in nylon with tensile strength losses of 5% or less.
Cytotoxic analogs of luteinizing hormone-releasing hormone containing doxorubicin or 2-pyrrolinodoxorubicin, a derivative 500-1000 times more potent.

Abstract Doxorubicin (DOX) and its daunosamine-modified derivative, 2-pyrrolino-DOX, which is 500-1000 times more active than DOX, were incorporated into agonistic and antagonistic analogs of luteinizing hormone-releasing hormone (LH-RH). The conjugation of DOX with LH-RH analogs was performed by using N-(9-fluorenylmethoxycarbonyl)-DOX-14-O-hemiglutarate, a dicarboxylic acid ester derivative of DOX. Coupling this derivative covalently to the epsilon-amino group of the D-Lys side chain of agonist [D-Lys6]LH-RH or antagonistic analog AC-D-Nal(2)-D-Phe(4Cl)-D-Pal(3)-Ser-Tyr-D-Lys-Leu-Arg-Pro-D-Ala-NH 2 [where Nal(2) = 3-(2-naphthyl)alanine, Pal(3) = 3-(3-pyridyl)alanine, and Phe(4CI) = 4-chlorophenylalanine] was followed by the removal of the 9-fluorenylmethoxycarbonyl protective group to yield cytotoxic derivatives of LH-RH analogs containing DOX. From these DOX containing LH-RH hybrids, intensely potent analogs with daunosamine-modified derivatives of DOX can be readily formed. Thus, cytotoxic LH-RH agonist containing DOX (AN-152) can be converted in a 66% yield by a reaction with a 30-fold excess of 4-iodobutyraldehyde in N,N-dimethylformamide into a derivative having 2-pyrrolino-DOX (AN-207). Hybrid molecules AN-152 and AN-207 fully preserve the cytotoxic activity of their radicals, DOX or 2-pyrrolino-DOX, respectively, in vitro, and also retain the high binding affinity of the peptide hormone portion of the conjugates to rat pituitary receptors for LH-RH. These highly potent cytotoxic analogs of LH-RH were designed as targeted anti-cancer agents for the treatment of various tumors that possess receptors for the carrier peptide. Initial in vivo studies show that the hybrid molecules are much less toxic than the respective cytotoxic radicals incorporated and significantly more active in inhibiting tumor growth.
Compressive myelopathy mimicking transverse myelitis.

Objectives:Spinal cord compression may be associated with a fusiform cord lesion on T2-weighted magnetic resonance imaging (MRI) images, leading to confusion with transverse myelitis and delaying effective surgical treatment.Results:We describe 5 patients referred for evaluation of suspected neuromy
On the Proper Order of Markov Chain Model for Daily Precipitation Occurrence in the Contiguous United States

Abstract Markov chains are widely used tools for modeling daily precipitation occurrence. Given the assumption that the Markov chain model is the right model for daily precipitation occurrence, the choice of Markov model order was examined on a monthly basis for 831 stations in the contiguous United States using long-term data. The model order was first identified using the Bayesian information criteria (BIC). The maximum-likelihood estimates of the Markov transition probabilities were computed from 100 bootstrapped samples and were then used to generate 50-yr precipitation occurrence series. The distributions of dry- and wet-spell lengths in the resulting series were then compared with observations using a two-sample Kolmogorov–Smirnov (K-S) test. The results suggest that the most parsimonious model, as identified by the BIC, usually (in approximately 68% of the cases) reproduced the wet- and dry-spell length distributions. However, the K-S test often indicated a second-order model when the BIC indicated...
Video streaming using whitespace spectrum for vehicular applications

We present Scout, a communication system leveraging TV whitespaces to support robust and high-speed streaming services. Scout uses two key techniques to improve video performance. First, it extends network coverage through an asymmetric network architecture where whitespace transceivers are used for the downlink direction while a cellular path is used for the uplink. Scout further leverages some unique opportunities that arise in vehicular systems. In particular, it sends a front radio to lookahead and identify the best channel parameters when the rear radio eventually reaches the forward post. We demonstrate the performance of Scout by using a single base station to stream a high-quality video to a vehicle driving along a 1.3km road stretch.
The role of superoxide anion in peroxidase-catalyzed chemiluminescence of luminol.

Abstract The chemiluminescence associated with peroxidation of luminol in buffered aqueous solution is a complex process involving several intermediates. It can be inhibited by removal of oxygen from the incubation medium. Superoxide radical is both an intermediate in this reaction and an essential component in light-producing steps. The importance of O 2 − in propagating this reaction was shown by the inhibition of luminescence by superoxide dismutase. A mechanism was proposed which is consistent with the data. It appears likely that the diverse biological effects of peroxidases are largely due to the reactivities of these intermediates and products.
High glucose, glucose fluctuation and carbonyl stress enhance brain microvascular endothelial barrier dysfunction: Implications for diabetic cerebral microvasculature.

We previously demonstrated that in normal glucose (5 mM), methylglyoxal (MG, a model of carbonyl stress) induced brain microvascular endothelial cell (IHEC) dysfunction that was associated with occludin glycation and prevented by N-acetylcysteine (NAC). Herein, we investigated the impact of high glucose and low GSH, conditions that mimicked the diabetic state, on MG-induced IHEC dysfunction. MG-induced loss of transendothelial electrical resistance (TEER) was potentiated in IHECs cultured for 7 or 12 days in 25 mM glucose (hyperglycemia); moreover, barrier function remained disrupted 6 h after cell transfer to normal glucose media (acute glycemic fluctuation). Notably, basal occludin glycation was elevated under these glycemic states. TEER loss was exaggerated by inhibition of glutathione (GSH) synthesis and abrogated by NAC, which corresponded to GSH decreases and increases, respectively. Significantly, glyoxalase II activity was attenuated in hyperglycemic cells. Moreover, hyperglycemia and GSH inhibition increased MG accumulation, consistent with a compromised capacity for MG elimination. α-Oxoaldehydes (MG plus glyoxal) levels were elevated in streptozotocin-induced diabetic rat plasma. Immunohistochemistry revealed a prevalence of MG-positive, but fewer occludin-positive microvessels in the diabetic brain in vivo, and Western analysis confirmed an increase in MG–occludin adducts. These results provide the first evidence that hyperglycemia and acute glucose fluctuation promote MG–occludin formation and exacerbate brain microvascular endothelial dysfunction. Low occludin expression and high glycated-occludin contents in diabetic brain in vivo are factors that would contribute to the dysfunction of the cerebral microvasculature during diabetes.
System for quantitative analysis of coronary calcification via electron-beam computed tomography

Electron beam computed tomography (EBCT) has provided a new tool for identification and possible quantification of coronary arterial plaque calcium. EBCT is the only imaging modality currently available which generates images of the spatial, temporal, and contrast resolution required for the identification of small foci of calcium and the potential for accurate quantification of calcium. Meanwhile, interest in quantification of coronary arterial calcium via EBCT and its correlation with severity of coronary atherosclerosis is increasing. Data remain inconclusive, but it appears that the reproducibility of quantitative grading of the extent of calcification by EBCT may be limited, in part, by the arbitrary nature of the scoring algorithm employed within the analysis tools currently provided by the EBCT manufacturer. It has not been possible to objectively determine optimum values for minimum plaque area and brightness threshold or to quantitatively determine whether single optimal values even exist. Also, although the current system tabulates the score, area, and mean attenuation for each plaque, the locations of the plaques are not reported.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Inborn errors of metabolism identified via newborn screening: Ten-year incidence data and costs of nutritional interventions for research agenda planning

Inborn errors of metabolism (IEM) are genetic disorders in which specific enzyme defects interfere with the normal metabolism of exogenous (dietary) or endogenous protein, carbohydrate, or fat. In the U.S., many IEM are detected through state newborn screening (NBS) programs. To inform research on IEM and provide necessary resources for researchers, we are providing: tabulation of ten-year state NBS data for selected IEM detected through NBS; costs of medical foods used in the management of IEM; and an assessment of corporate policies regarding provision of nutritional interventions at no or reduced cost to individuals with IEM. The calculated IEM incidences are based on analyses of ten-year data (2001-2011) from the National Newborn Screening Information System (NNSIS). Costs to feed an average person with an IEM were approximated by determining costs to feed an individual with an IEM, minus the annual expenditure for food for an individual without an IEM. Both the incidence and costs of nutritional intervention data will be useful in future research concerning the impact of IEM disorders on families, individuals and society.
Synthesis of methyl 3-deoxy-3-methylaminoarabinopyranoside, a component of some aminoglycoside antibiotics

Abstract Amino sugar 1 has been synthesized in racemic form as a mixture of anomers from sorbic aldehyde. An intramolecular N-sulfinyl dienophile Diels-Alder strategy was used to stereospecifically generate the chiral centers of pentose 1 .
In Search of Kilometer Zero: Digital Archives, Technological Revisionism, and the Sino-Vietnamese Border

B?i Minh Qu?c left for the border in late 2001. His clandestine trip, which took nearly a month to complete on a 50cc Honda Cub motorcycle, retraced the peri meter of Vi?t B?c, the name for the mountainous region that stretches across ten provinces in northeastern Vietnam. Qu?c, a poet of considerable repute, docu mented the highpoints of the ride in verse.1 But the region's rugged beauty, which holds a prominent place in official histories of the anti-colonial struggle against the French and those who collaborated with them, was not the real reason for his quest. Nor was the region's more recent reincarnation as a social ist battleground during the Third Indochina War with the People's Republic of China, a conflict that killed and wounded an estimated one hundred thousand people in the space of a month.2 Instead, Qu?c's self-appointed task was to find the current location of "Kilometer Zero" {C?y s? kh?ng) along the Sino Vietnamese border?a difficult proposition since it appears nowhere on official maps of the country. Nonetheless, the toponym is commonly used to refer to the precise spot in Lang Son Province where National Highway 1 A, the only paved road to traverse the entire length of Vietnam, begins its long journey south. For many Vietnamese, Kilometer Zero is inextricably linked to Ai Nam Quan, an arched gateway first constructed perhaps as early as the fifteenth
Differential lateralization of trait anxiety and trait fearfulness: Evoked potential correlates

Abstract There is an ongoing debate on whether the terms anxiety and fear denote distinct states. Brain imaging studies suggest they may indeed be dissociable and are differentially lateralized. A study of 54 normal college students successfully found doubly dissociable electrophysiological correlates of trait anxiety and fearfulness that had the predicted laterality. Trait anxious participants displayed a left-lateralized visual N1 (localized to the temporo-parietal junction) whereas trait fearful participants presented a right-lateralized P1r (localized to the superior parietal region). These findings support the proposal that trait anxiety and trait fearfulness are distinct personality dimensions with distinctive patterns of laterality.
The communal crop: modulation of sucrose response thresholds of pre-foraging honey bees with incoming nectar quality

We examined whether the quality (concentration) of incoming sucrose solutions returned by foraging honey bees affected the response thresholds of pre-foraging members of the colony. Six pairs of colonies were given ad libitum access to sucrose solution feeders. A colony from each pair was switched from 20–50% sugar concentration feeders while the other continued to have access to 20% sucrose feeders. Proboscis extension response (PER) scores to an increasing series of sucrose concentrations were significantly higher in pre-foragers of colonies foraging on 20% sucrose throughout compared to pre-foragers in colonies where foraging was switched to 50% sucrose. Although all colonies had honey stores, the concentration of sugar solution in non-foraging bees’ crops were significantly lower in bees from colonies foraging on 20% sucrose compared to those from colonies foraging on 50% sucrose. Because response thresholds to sugar of young bees were modulated by the concentration of sucrose solution returned to colonies, we repeated the 2000 study of Pankiw and Page that potentially confounded baseline response thresholds with modulated scores due to experience in the colony. Here, we examined PER scores to sucrose in bees within 6 h of emergence, prior to feeding experience, and their forage choice 2 to 3 weeks later. Pollen foragers had higher PER scores as newly emerged bees compared to bees that eventually became nectar foragers. These results confirm those of the 2000 study by Pankiw and Page. Combined, these experiments demonstrate that variation in pre-forager sucrose response thresholds are established prior to emerging as adults but may be modulated by incoming resources later on. Whether this modulation has long-term effects on foraging behavior is unknown but modulation has short-term effects and the potential to act as a means of communication among all bees in the colony.
Assessing Service Level Targets in Production and Inventory Planning

In production and stock planning, the relationship between customer service, defined as the ability to meet demand for finished goods from in-stock inventory, and expected profits or expected costs can be represented by a simple reliability curve. The shape of this curve depends upon the parameters of the demand process, specifically the expected level of demand, standard deviation and correlation structure, as well as upon the capacities and initial state of the production and inventory system. A model is presented which explicitly determines this trade-off curve for a firm. The model is intended both as an operational model to aid managers in setting revenue and service targets which are compatible with the capacities and resources of the firm, and as a tool for exploring relationships between the parameters of the demand process and the constraints of the physical production and inventory system. The results illustrate that the level of risk depends strongly on the variability of the demand process, the cost structure, the capacities and initial state of the system and, to a lesser extent, the correlation in demand between succeeding periods. Results suggest that establishing service level targets consistent with the firm's strategic orientation must be done in consideration of both the characteristics of the demand process and the capacities of the production and inventory system. The model provides a tool for estimating the premium above unit cost which must be paid to provide a designated service level.
Ventral mesoderm induction and patterning by bone morphogenetic protein heterodimers in Xenopus embryos

Bone morphogenetic proteins (BMPs) perform diverse functions in vertebrate development. Here we demonstrate that the heterodimeric BMP-4/7 protein directly induces ventral mesoderm and blood in Xenopus animal caps, and BMP-2/7 heterodimers may function similarly. We also provide indirect evidence that BMP heterodimers function in embryos, using assays with dominant-negative BMP ligands. Homodimeric BMP-2 and BMP-4 proteins do not induce mesoderm, but they ventralize mesoderm induction by activin. In contrast, BMP-7 protein interferes with mesoderm induction by activin, but BMP-7 stimulates ventral mesoderm induction by the heterodimer, BMP-4/7. This novel property of BMP-7 distinguishes it from other BMPs. BMP-7 may therefore function in early embryogenesis to antagonize activin signals and potentiate BMP signals. We propose that BMP heterodimers convey signals for ventral mesoderm induction and patterning in Xenopus development.
Lone-pair orbital interactions in polythiaadamantanes.

The electronic structures of a series of polythiaadamantanes from thiaadamantane through 2,4,6,8,9,10-hexathiaadamantane (HTA) have been analyzed using density functional theory calculations in conjunction with Huckel and natural bond orbital analysis. The effects of multiple sulfur p-type lone-pair orbital interactions on ionization potentials, hole mobilities, and electronic coupling have been determined. An overall increase in the average energy of the lone-pair orbitals as the number of sulfur atoms increases is predicted, with the exact positioning of the HOMO depending on specific lone-pair interactions. Separation of through-bond (TB) and through-space (TS) interactions between intramolecular sulfur atoms has been performed using localized molecular orbitals and model systems based on interacting hydrogen sulfide molecules. TB interations were found to reduce orbital splitting, while TS interactions were found to increase orbital splitting. TS interactions were more or less constant from one polythiaadamantane to the next, and the contributions of TB effects to individual orbital energies vary depending on the relative orientation of sulfur atoms as determined by the sigma molecular framework. Electronic coupling between intermolecular sulfur lone-pair orbitals was determined by investigating unique dimer pairs observed in the crystal structure of HTA. Electronic coupling is not as strong as expected given the short intermolecular S-S distances observed in the crystal structure. In general, B3LYP/6-31G(d) and B3LYP/6-311+G(d,p) give very similar orbital energies and splittings.
Hematin formation and pancreatitis.

Abstract Production of hematin from hemoglobin in vitro is augmented by a mixture of powdered pancreatic enzymes and human pancreatic juice. Those enzymes which most affected the rate of conversion of hemoglobin to hematin were lipase, elastase, and trypsin. These same enzymes were also most active in hematin production from red cells.
Emotional/Behavioral Difficulties and Mental Health Service Contacts of Students in Special Education for Non–Mental Health Problems

BACKGROUND: Emotional/behavioral difficulties and mental health (MH) service contacts of 3 groups of youth were compared: students in special education for non-MH problems, students in special education for MH problems, and youth not in special education. METHODS: Parents reported the characteristics, special education placement, emotional/behavioral difficulties, and MH service contacts of 25,122 youth aged 6-17 years in the National Health Interview Survey. RESULTS: Two thirds of students in special education received special education services for non-MH problems. Among students in special education for non-MH problems, 17% had serious emotional/behavioral difficulties compared with 51% of students in special education for MH problems and 4% of youth not in special education. MH service contacts were examined only for youth whose difficulties significantly interfered with their ability to function in or out of school. Among youth with serious difficulties, the percentage of youth without a recent MH service contact was greater for students in special education for non-MH problems (40%) and youth not in special education (47%) compared with students in special education for MH problems (13%). CONCLUSIONS: Compared with youth not in special education, students in special education for non-MH problems were 4 times more likely to have serious emotional/behavioral difficulties but were just as likely as youth not in special education to lack a recent MH service contact. Study findings provide a national context for considering the MH screening/evaluation needs of students receiving special education for non-MH problems.
Transactions costs and the relationship between put and call prices

Abstract The relationship between prices of puts and calls on securities that is suggested by the theory of efficient markets is developed and empirically tested in this paper. We find that the basic model is not supported unless rather large transactions costs are included. Moreover, the transactions costs that must be assumed to make the model consistent with the data are so large as to raise troublesome questions as to whether there were unexploited profit opportunities in the options market at least during the 1967–1969 period. We also find that similar deviations from the efficient market hypothesis have shown up in related work by other researchers but that their explanations of these results appear to be incorrect on theoretical grounds or too sanguine.
Specification of Neuropeptide Cell Identity by the Integration of Retrograde BMP Signaling and a Combinatorial Transcription Factor Code

Individual neurons express only one or a few of the many identified neurotransmitters and neuropeptides, but the molecular mechanisms controlling their selection are poorly understood. In the Drosophila ventral nerve cord, the six Tv neurons express the neuropeptide gene FMRFamide. Each Tv neuron resides within a neuronal cell group specified by the LIM-homeodomain gene apterous. We find that the zinc-finger gene squeeze acts in Tv cells to promote their unique axon pathfinding to a peripheral target. There, the BMP ligand Glass bottom boat activates the Wishful thinking receptor, initiating a retrograde BMP signal in the Tv neuron. This signal acts together with apterous and squeeze to activate FMRFamide expression. Reconstituting this "code," by combined BMP activation and apterous/squeeze misexpression, triggers ectopic FMRFamide expression in peptidergic neurons. Thus, an intrinsic transcription factor code integrates with an extrinsic retrograde signal to select a specific neuropeptide identity within peptidergic cells.