cssi/SciSciGPT-SciSciNet huggingface dataset:
Relative gas-phase acidities from triple quadrupole mass spectrometers

Abstract Chemical ionization of mixtures of aliphatic acids yields proton-bound dicarboxylate anions, R 1 CO 2 − ⋯H + ⋯ − O 2 CR 2 , which are mass-selected and subjected to collision-induced dissociation (CID) at 5–30 eV. The branching ratio for formation of the principal fragments, R 1 CO 2 − and R 2 CO 2 − , is used to follow internal energy deposition in the proton-bound anion as a function of collision energy and target pressure. Increased energy deposition is observed with increases in pressure and in translational energy, although the branching ratio also shows effects attributed to severe discrimination against the lighter fragment at pressures exceeding the limit for single collisions. These discrimination effects are most pronounced at low collision energy and are not observed (for argon target gas) at the higher energies. The relative abundances of the carboxylate fragments correlate with their relative proton affinities. In this, and in the fact that quantitative assignments of relative proton affinities are possible, the triple quadrupole methodology gives results which parallel those obtained using keV beams in sector mass spectrometers. Detailed similarities between the low- and high-energy studies include the anomalous behavior of formic acid in both and quantitative agreement in measured gas-phase acidities for valeric and hexanoic acid.
Dimorphecolic Acid Is Synthesized by the Coordinate Activities of Two Divergent Δ12-Oleic Acid Desaturases

Dimorphecolic acid (9-OH-18:2Delta(10)(trans)(,12)(trans)) is the major fatty acid of seeds of Dimorphotheca species. This fatty acid contains structural features that are not typically found in plant fatty acids, including a C-9 hydroxyl group, Delta(10),Delta(12)-conjugated double bonds, and trans-Delta(12) unsaturation. Expressed sequence tag analysis was conducted to determine the biosynthetic origin of dimorphecolic acid. cDNAs for two divergent forms of Delta(12)-oleic acid desaturase, designated DsFAD2-1 and Ds-FAD2-2, were identified among expressed sequence tags generated from developing Dimorphotheca sinuata seeds. Expression of DsFAD2-1 in Saccharomyces cerevisiae and soybean somatic embryos resulted in the accumulation of the trans-Delta(12) isomer of linoleic acid (18: 2Delta(9)(cis)(,12)(trans)) rather than the more typical cis-Delta(12) isomer. When co-expressed with DsFAD2-1 in soybean embryos or yeast, DsFAD2-2 converted 18:2Delta(9)(cis)(,12)(trans) into dimorphecolic acid. When DsFAD2-2 was expressed alone in soybean embryos or together with a typical cis-Delta(12)-oleic acid desaturase in yeast, trace amounts of the cis-Delta(12) isomer of dimorphecolic acid (9-OH-18:2Delta(10)(trans,)(12)(cis)) were formed from DsFAD2-2 activity with cis-Delta(12)-linoleic acid [corrected]. These results indicate that DsFAD2-2 catalyzes the conversion of the Delta(9) double bond of linoleic acid into a C-9 hydroxyl group and Delta(10)(trans) double bond and displays a substrate preference for the trans-Delta(12), rather than the cis-Delta(12), isomer of linoleic acid. Overall these data are consistent with a biosynthetic pathway of dimorphecolic acid involving the concerted activities of DsFAD2-1 and DsFAD2-2. The evolution of two divergent Delta(12)-oleic acid desaturases for the biosynthesis of an unusual fatty acid is unprecedented in plants.
A multivariate study of resource partitioning in soft bottom lotic Chironomidae

For two years a community of larval chironomid midges was studied in a sandy-run portion of a fourth order natural stream in SE Ohio, U.S.A. in order to determine if the species partitioned the spatial resources. The habitat structure was simplified from ten habitat variables to three significant principal components. The three eigenvectors were easily interpreted as ‘sediment size’, ‘sediment heterogeneity’, and ‘organic deposition’. Species abundances were loaded on these axes and niche metrics examined. Strong differences in habitat preference were demonstrated for midge species on each component. Also, there were no differences in distributions for the intraspecific instars for each species tested at a given time, but for each of the instars tested, their distributions were found to change from time to time. Apparently, individuals of a species, regardless of instar, simultaneously choose the same habitat, however, the preferred habitat may shift temporally due to change in resource availability, or niche expansion or compression due to competition.
Length of Stay and Mortality Associated With Febrile Neutropenia Among Children With Cancer

Purpose The aim of this study was to evaluate risk factors for longer length of stay (los) and mortality among hospitalized children with cancer who have febrile neutropenia. Methods This study involved analysis of longitudinal data from the University HealthSystem Consortium database from 1995 to 2002. All patients who were 21 years or younger, with diagnostic codes for both neoplastic disease and febrile neutropenia at discharge, were included. Results A total of 12,446 patients were identified for the study. The los was 5 days or less for 6,799 patients, and greater than 5 days for 5,647 patients. The mortality rate was 3%. On bivariate analysis, race, age, cancer type, and associated complications (bacteremia/sepsis, hypotension, pneumonia, and fungal infections) were significantly associated with longer length of stay and death. On multivariate analysis, age group, race, cancer type (acute myeloid leukemia, multiple cancers v acute lymphoblastic leukemia), and the complication variables were signific...
Corpus Cavernosum-Spongiosum Fistula After Blunt Pelvic Trauma: Successful Resolution with Digoxin

Traumatic urethrocavernous communications may develop as an acute or late complication after blunt penile trauma, usually associated with penile fracture.l.2 In approximately a third of penile fractures an associated urethral injury results in urethrocorporeal communication. Urethrocavernous fistula as a late sequela of penile or perineal trauma without penile fracture has rarely been reported. Successful treatment depends on fistula size. Small fistulas appear to resolve with conservative management, while larger fistulas may require surgical repair. We report a case in which a urethrocavernous fistula secondary to blunt penile trauma with no associated penile fracture was successfully treated with oral digoxin therapy. CASE REPORT A 17-year-old man received a direct blow to the penis and pelvis with a soccer ball. Several days after the injury he noticed bleeding from the urethra only during erections. He was not sexually active and spontaneous erections were normal before the injury. The fistula did not heal spontaneously. Hematuria persisted despite oral antibiotic therapy given anecdotally due to the possibility of lower urinary tract infection and oral phenylpropanolamine given with the intention of suppressing nocturnal erections. Retrograde urethrography and cystoscopy were performed 6 weeks after the injury with the patient under general anesthesia. Urethrography showed no abnormalities and cystoscopy demonstrated a small area thought to be the source of bleeding in the bulbous urethra along the right side. This site was fulgurated with the Bugbee electrode but bleeding with erections persisted. Penile color duplex ultrasonography after injection of 20 pg. prostaglandin El revealed normal arterial flow and no fistulous process. Dynamic infusion cavernosography showed a small fistula between the corpus cavernosum and spongiosum (see figure). Digoxin therapy (0.25 mg. daily) was begun orally based on recent evidence that this drug may be associated with impotence by inhibiting va~orelaxation.~ Digoxin and serum electrolyte levels were monitored weekly. Bleeding resolved after digoxin levels became therapeutic (0.77 pg./l., therapeutic range 0.5 to 2.0). After 8 weeks of therapy bleeding ceased and repeat dynamic infusion cavernosography revealed a healed fistula. Digoxin was discontinued and there have been no further episodes of bleeding. The patient reports normal spontaneous erections. DISCUSSION Our case and that of Motiwalaz involved a urethrocavernous fistula of the penile urethra secondary to blunt penile trauma without a concomitant penile fracture. This finding is unusual. Urethrocavernous fistula as a late sequela of penile or perineal trauma without penile fracture has rarely been reported. Such fistulas are usually associated with a penile fracture. The hallmark diagnostic sign is gross hematuria with erection and diagnosis is made on retrograde urethrog
An examination of present research on the female entrepreneur — Suggested research strategies for the 1990's

Intensive investigations into female entrepreneurships are a relatively recent research phenomenon. Advances in the past five years, while dramatic, find the field in an initial stage of paradigm development. Individual studies appear fragmented, unrelated, and seem to describe only small segments of the female entrepreneurial population and more frequently than not apply theoretical tools developed in other areas which are neither reliable or valid. This article examines a number of current research and methodological issues, presents a descriptive analysis of the traditional and modern female entrepreneur, suggests focal areas for research oriented toward the establishment of typologies, models and theory development.
Ultra-thin single crystal silicon modules capable of 450 W/kg and bending radii <1mm: Fabrication and characterization

We present ultra-thin single crystal mini-modules built with specific power of 450 W/kg capable of voltages of >1000 V/cm2. These modules are also ultra-flexible with tight bending radii down to 1 mm. The module is composed of hundreds of back contact microcells with thicknesses of approximately 20 μm and diameters between 500-720 μm. The cells are interconnected to a flexible circuit through solder contacts. We studied the characteristics of several mini-modules through optical inspection, evaluation of quantum efficiency, measurement of current-voltage curves, and temperature dependence. Major efficiency losses are caused by missing cells or non-interconnected cells. Secondarily, damage incurred during separation of 500 μm cells from the substrate caused material detachment. The detachment induced higher recombination and low performance. Modules made with the larger cells (720 μm) performed better due to having no missing cells, no material detachment and optimized AR coatings. The conversion efficiency of the best mini module was 13.75% with a total Voc = 7.9 V.
Walking cadence effect on plantar pressures

Abstract Objective: Prior studies have examined the effect of cadence on ground reaction forces by use of a force plate. Force plate studies generally analyze isolated steps and do not provide insight into ongoing step-to-step variations or in-shoe plantar pressures. The objective of this study was to evaluate the effect of walking cadences on in-shoe plantar pressures over extended periods of continuous walking. Design: Nonrandomized control trial. Setting: Laboratory. Patients or Other Participants: Volunteer sample of 8 able-bodied subjects. Interventions: In-shoe plantar pressures were studied during four minutes of continuous walking at controlled cadences of 70, 80, 90, 100, 110, and 120steps/min. For each cadence more than 200 steps were analyzed for each of the 8 subjects. Main Outcome Measures: Pressure-time integrals, foot-to-floor contact durations, and peak pressures at all 14 locations were processed for each step. Changes were calculated compared to values at 70steps/min. Results: With increasing cadence, mean pressure-time integrals continuously decreased (45% at 120steps/min); mean foot-to-floor contact durations continuously decreased (64% at 120steps/min); and mean peak pressures increased (119% at 120steps/min). Conclusions: Our results show that as walking cadence increases, pressure-time integrals and foot-to-floor contact durations decrease, and peak plantar pressures increase. This is clinically relevant to all kinetic gait studies because our results suggest that normal values should be established for each cadence.
Antenatal fetal testing in well-controlled GDMA2 patients – does it correlate with glycemic control? Is it necessary?

Abstract Background: Because GDMA2 pregnancies are believed to be at increased risk of perinatal morbidity and mortality, fetal surveillance is initiated in the third trimester. Objectives: To correlate the results of antepartum fetal surveillance with glycemic control and fetal outcomes. Materials and Methods: A retrospective chart study of 421 pregnant women with diabetes was performed over a 7-year period. Patients with GDMA1, preexisting hypertension, diabetes, severe preeclampsia, fetal growth restriction, noncompliance, and substance abuse were excluded. For study purposes good glycemic control was fasting (F) and 2-hour postprandial (PP) glucose values of 150 mg/dL. The mean of the F and 2-hour PP values was noted on the day of and the day preceding the nonstress test (NST). The number of NSTs and biophysical profile(s) (BPPs) each patient underwent, the frequency of abnormal test results dictating further testing/delivery, and the fetal outcomes were recorded and correlated with glycemic control. Results: One hundred fifty-two patients in the study underwent 1,555 NSTs. Of the NSTs, 7.4 % were nonreactive, and glycemic control was good in 4.2% and fair or poor in 3.0%. There was no statistically significant difference. Further data, including glycemic control in reactive NSTs and fetal outcomes, will be presented. Conclusions: The role of antepartum fetal surveillance in GDMA2 patients, especially well-controlled patients, remains to be determined.
CVD-titanium carbonitride coatings as corrosion-preventing barriers for steel in acid-brine steam at 200°C

Abstract Titanium carbonitride [(Ti(CN)] coating was deposited onto steel surfaces by chemical vapor deposition (CVD) technology at a moderate temperature; then, its effectiveness in preventing the corrosion of steel was evaluated in an acid-brine geothermal environment at 200°C under a hydrothermal pressure of 1.45 MPa. Two undesirable attributes caused its failure as a corrosion-preventing coating: one factor was the susceptibility of Ti(CN) to oxidation reactions with aqueous steam, leading to the formation of TiO 2 scale. Furthermore, this TiO 2 scale then was transformed into water-soluble TiCl 4 salt by the attack of acid brine, thereby resulting in its dissolution in the aqueous medium. The corrosion of Ti(CN) in such an environment took place through the precesses of oxidation→chlorination→dissolution. The other factor was the inherent defects and pores in the coating layers, allowing the corrosive species to infiltrate easily. In fact, corrosion products from the underlying steel were observed at several different locations in the coating's surfaces.
An open-label, uncontrolled, prospective trial of pefloxacin prophylaxis in gynecologic surgery: an evaluation of efficacy

Abstract In a prospective, observational study of antibiotic prophylaxis in gynecologic surgery, the efficacy of pefloxacin in preventing post-operative infections was tested in 178 patients (median age, 47 years) who were hospitalized to undergo abdominal or vaginal gynecologic surgery. Pefloxacin was administered in a single intravenous dose before the surgery in the absence of clinical symptoms, signs, and laboratory data consistent with an infectious etiology. The failure rate of pefloxacin after abdominal surgery was 6.9%, whereas for the vaginal route it was 5.3%. No statistically significant difference was found between the two surgical approaches when the outcome of antibiotic prophylaxis was compared. Failures were related to fever of unknown origin (2 patients), wound infection (3), subfascial abscess (1), and urinary tract infection (1) for abdominal surgery, and to vaginal cuff abscess (1), urinary tract infection (1), pelvic cellulitis (1), and asymptomatic bacteriuria (1) for vaginal surgery. No adverse effects were reported in patients after administration of pefloxacin. None of the patients reported postoperative infections 6 weeks after discharge from the hospital. The use of pefloxacin, a drug with a long half-life and particular efficacy in the urinary tract, appears to be a good choice in a gynecologic surgery because it reduces the incidence of bacteriuria, the principal cause of infectious complications after this type of surgery. These observational results should be confirmed by randomized, masked studies of antibiotic prophylaxis comparing pefloxacin with cephalosporins, semisynthetic penicillins, and other drugs in gynecologic surgery.
OPTIMIZATION AND VALIDATION OF REVERSE PHASE LIQUID CHROMATOGRAPHIC METHOD FOR ESTIMATION OF CETIRIZINE MANNITOL ESTER IMPURITY IN CETIRIZINE HYDROCHLORIDE CHEWABLE TABLET

A novel gradient reverse phase liquid chromatographic (HPLC) method was developed for the determination of cetirizine mannitol ester impurity in cetirizine chewable tablet where mannitol was used as one of excipient and cetirizine mannitol ester impurity was formed during thermal stress tablet. The method was developed using ZodiacSIL 120-C-C18 AQ, 150 × 4.6 mm, 3 µm column with mobile phase containing a gradient mixture of solvent A and B. 0.01 M phosphate buffer (sodium dihydrogen phosphate monohydrate), pH 7.0 was used as buffer. Buffer pH 7.0 and methanol in 80:20 v/v ratios was used as solvent A and buffer pH 7.0 and methanol in 20:80 v/v ratio was used as solvent B. The gradient program (T/%B) was set as 0/70, 15/70, 20/85, 22/100, 25/100, 26/70, and 32/70 with a flow rate of 0.9 mL/minute. The eluted compounds cetirizine mannitol ester impurity and cetirizine hydrochloride peak were monitored at 230 nm. The run time was 32 min. Cetirizine chewable tablet was subjected to the stress conditions of ox...
Urine biomarkers predict acute kidney injury and mortality in very low birth weight infants.

Objectives To test the hypothesis that noninvasive urinary biomarkers may improve early identification, differentiate causes, and predict outcomes of acute kidney injury (AKI) in very low birth weight subjects. Study design We performed 2 nested case-control studies to compare the ability of 6 urine biomarkers to predict AKI (rise in serum creatinine of at least 0.3 mg/dL) and mortality (death before 36 weeks postmenstrual age). Results Compared to subjects without AKI (n = 21), those with AKI (n = 9) had higher maximum neutrophil gelatinase-associated lipocalin (OR = 1.2 [1.0, 1.6]; P P P P Conclusions Urinary biomarkers can predict AKI and mortality in very low birth weight infants independent of gestational age and birth weight.
Packing Length Influence in Linear Polymer Melts on the Entanglement, Critical, and Reptation Molecular Weights

We have shown in previous studies that the entanglement molecular weight for a polymer melt, Me, is related by a power law to p, the packing length of the polymer species. We now find that power laws also describe the molecular weights characterizing the melt viscosity, Mc marking the onset of entanglement effects and Mr the crossover to the reptation form. The packing length exponents for Me, Mc, and Mr differ significantly, however. The long-held notion that the ratio Mc/Me has the same value for all species is therefore incorrect. Further, the observed and predicted values of Mr for two species, 1,4-polybutadiene and polyisobutylene, have been found to agree, within the uncertainties, with the projected values. Finally, the variations with packing length are such that all three characteristic molecular weights would appear to converge on the same value near p = 9 A. As yet, no species with such a large packing length has been completely studied rheologically. But the range is not outlandish and is clea...
Immunohistochemical localization of an HIV epitope in cerebral aneurysmal arteriopathy in pediatric acquired immunodeficiency syndrome (AIDS).

A 6-year-old boy with acquired immunodeficiency syndrome (AIDS) developed aphasia and quadriplegia 3 months before his death. Cerebral vascular ectasia and multiple cerebral infarcts were noted on premortem radiological studies. Postmortem evaluation revealed diffuse aneurysmal dilatation of the circle of Willis associated with fresh and organizing thrombi, destruction of the elastic lamina, and marked intimal fibroplasia. Multiple cerebral infarcts and subacute AIDS encephalitis with basal ganglia calcification were also present. Immunohistochemistry with a monoclonal antibody (anti-gp41) to human immunodeficiency virus (HIV) demonstrated positively stained cells in the arterial wall of the circle of Willis and in the cerebral parenchyma. Double immunostaining demonstrated that gp41-positive cells in the circle of Willis were also positive for a macrophage marker or leukocyte-common antigen, but not with an endothelial marker. Some macrophages or microglia in the cerebrum were also colabeled with anti-gp...
Genetic feminization of brain structures and changed sexual orientation in male Drosophila

The neural basis of sexual orientation in Drosophila was studied by the production of males with regionally feminized brains. Such flies express the female form of the sex determination gene transformer in a limited number of neurons under the control of GAL4 enhancer trap inserts. This method facilitated the creation of lines with a stable pattern of feminization. In tests of sexual preferences, flies that were feminized in a portion of the antennal lobes or in a subset of the corpora pedunculata (mushroom bodies) courted both males and females. These two brain structures, both of which are involved in olfactory processing, may function in the recognition of sex-specific pheromones, in the control of sex-specific behaviors, or both.
Mechanistic Studies of Cu(II) Binding to Amyloid-β Peptides and the Fluorescence and Redox Behaviors of the Resulting Complexes

Due in large part to the lack of crystal structures of the amyloid-β (Aβ) peptide and its complexes with Cu(II), Fe(II), and Zn(II), characterization of the metal−Aβ complex has been difficult. In this work, we investigated the complexation of Cu(II) by Aβ through tandem use of fluorescence and electron paramagnetic resonance (EPR) spectroscopies. EPR experiments indicate that Cu(II) bound to Aβ can be reduced to Cu(I) using sodium borohydride and that both Aβ−Cu(II) and Aβ−Cu(I) are chemically stable. Upon reduction of Cu(II) to Cu(I), the Aβ fluorescence, commonly reported to be quenched upon Aβ−Cu(II) complex formation, can be regenerated. The absence of the characteristic tyrosinate peak in the absorption spectra of Aβ−Cu(II) complexes provides evidence that the sole tyrosine residue in Aβ is not one of the four equatorial ligands bound to Cu(II), but remains close to the metal center, and its fluorescence is sensitive to the copper oxidation state and perturbations in the coordination sphere. Further...
The Hexosamine Signaling Pathway: Deciphering the "O-GlcNAc Code"

A dynamic cycle of addition and removal of O-linked N-acetylglucosamine (O-GlcNAc) at serine and threonine residues is emerging as a key regulator of nuclear and cytoplasmic protein activity. Like phosphorylation, protein O-GlcNAcylation dramatically alters the posttranslational fate and function of target proteins. Indeed, O-GlcNAcylation may compete with phosphorylation for certain Ser/Thr target sites. Like kinases and phosphatases, the enzymes of O-GlcNAc metabolism are highly compartmentalized and regulated. Yet, O-GlcNAc addition is subject to an additional and unique level of metabolic control. O-GlcNAc transfer is the terminal step in a "hexosamine signaling pathway" (HSP). In the HSP, levels of uridine 5'-diphosphate (UDP)-GlcNAc respond to nutrient excess to activate O-GlcNAcylation. Removal of O-GlcNAc may also be under similar metabolic regulation. Differentially targeted isoforms of the enzymes of O-GlcNAc metabolism allow the participation of O-GlcNAc in diverse intracellular functions. O-GlcNAc addition and removal are key to histone remodeling, transcription, proliferation, apoptosis, and proteasomal degradation. This nutrient-responsive signaling pathway also modulates important cellular pathways, including the insulin signaling cascade in animals and the gibberellin signaling pathway in plants. Alterations in O-GlcNAc metabolism are associated with various human diseases including diabetes mellitus and neurodegeneration. This review will focus on current approaches to deciphering the "O-GlcNAc code" in order to elucidate how O-GlcNAc participates in its diverse functions. This ongoing effort requires analysis of the enzymes of O-GlcNAc metabolism, their many targets, and how the O-GlcNAc modification may be regulated.
Coal Fired MHD Technology: A Prospective Power Generation Method

By passing the combustion gases through magnetic field, magneto generator converts heat directly to electric power without moving parts. The inherent characteristic of high efficiency and low emission makes Coal fired MHD power generation technology attractive to be a potential alternative power generation method in the future. This paper presents the working principle of MHD generator and describes the coal fired MHD power plant systems and the key components in these systems. It also reviews the batch research of Department of Energy on coal fired MHD electric power generation—Proof of Concept Program from 1987 to 1993 and states some challenges remained on its way to commercial use.Copyright © 2003 by ASME
Direct Measurement of the Polarization Dependence of Si(111)2×1 Surface-State Absorption by Use of Photothermal Displacement Spectroscopy

The polarization dependence of midgap optical absorption (0.38--0.51 eV) by Si(111)2 x 1 single-domain surfaces has been measured directly by photothermal displacement spectroscopy. The absorption is strongest when the light is polarized perpendicular to the period-doubling direction of the 2 x 1 reconstruction and is reduced by at least 95% when the polarization is rotated by 90/sup 0/. This result supports the ..pi..-bonded chain model of the Si(111)2 x 1 surface reconstruction.
CONVERGENT SYNTHESIS OF N-LINKED GLYCOPEPTIDES ON A SOLID SUPPORT

Solid-supported synthesis can be conducted to produce a variety of glycopeptides in good overall yields. The carbohydrates are formed by the glycal assembly method. The polymer-bound construct terminates in a glycal. The terminal double bond can be functionalized to provide a C2−N-acetyl glucosamine linkage with an amino group in the anomeric position. The latter can be coupled, in a convergent manner, to the γ-carboxyl group of an aspartyl residue on a preformed peptide. Iodosulfonamidation of the polymer-bound glucal to the N-acetyl glucosamine using anthracenesulfonamide was crucial for the success of the solid-phase synthesis. This general method was employed in the formation of a variety of glycopeptides.
A chemical survey of seeds of the genus Gossypium

Abstract The amino acid patterns of the seed proteins and the fatty acid patterns of the seed oils of twenty-five species of Gossypium are reported. A genome specific pattern was not found for either the amino acids or the fatty acids or for the seed index. G. anomalum differed markedly from the other species in its seed oil; the kernel contained 74·8 per cent oil and the oil contained about 20 per cent of the fatty acid having an equivalent chain length of 19·6 which was not present in the seed oil of any of the other species. The gossypol content of the defatted seed meals ranged from 0·12 and 0·13 for G. stocksii and G. incanum to 9·25 per cent for G. klotzschianum (var. davidsonii ), and a multiple range classification of the species in accordance with the gossypol content groups the species into specific genomes, with exception of G. gossypioides and G. longicalyx which seem to be out of place. I.r. spectra of the acetone-hexane-water extracts of hexane-defatted meals showed specific differences among the species and led to the grouping of the twenty-five species into their specific genomes; exceptions were G. gossypioides, G. longicalyx and G. tomentosum .
SPARC mediates focal adhesion disassembly in endothelial cells through a follistatin-like region and the Ca2+-binding EF-hand

SPARC is a one of a group of extracellular matrix proteins that regulate cell adhesion through a loss of focal adhesion plaques from spread cells. We previously reported that SPARC reduced the number of bovine aortic endothelial (BAE) cells positive for focal adhesions [Murphy-Ullrich et al. (1991): J Cell Biol 115:1127-1136]. We have now characterized the effect of SPARC on the cytoskeleton of BAE cells. Addition of SPARC to spread BAE cells caused a dose-dependent loss of focal adhesion-positive cells, that was maximal at approximately 1 microgram/ml (0.03 microM). Consistent with the loss of adhesion plaques as detected by interference reflection microscopy, vinculin appeared diffuse and F-actin was redistributed to the periphery of cells incubated with SPARC. However, the distribution of the integrin alpha v beta 3 remained clustered in a plaque-like distribution. These data, and the observation that SPARC binds to BAE cells but not to the extracellular matrix, indicate that SPARC acts via interactions with cell surface molecules and not by steric/physical disruption of integrin-extracellular matrix ligands. To determine the region(s) of SPARC that mediate a loss of focal adhesions, we tested peptides from the four distinct regions of SPARC. The cationic, cysteine-rich peptide 2.1 (amino acids 54-73) and the Ca(2+)-binding EF-hand-containing peptide 4.2 (amino acids 254-273) were active in focal adhesion disassembly. Furthermore, antibodies specific for these regions neutralized the focal adhesion-labilizing activity of SPARC. These results are consistent with previous data showing that peptide 2.1 and 4.2 interact with BAE cell surface proteins and indicate that the loss of focal adhesions from endothelial cells exposed to SPARC is a receptor-mediated event.
The role of the (6−4) photoproduct in ultraviolet light-induced transition mutations in E. coli

Available evidence rules out the possibility that cyclobutane dimers are the major premutagenic lesions responsible for point mutations at sites of adjacent pyrimidine residues in the experiment systems examined to date in sufficient detail, that is, UV-induced mutations in chromosome loci in E. coli and UV-induced mutations in the cI gene of phage lambda. However, it is likely that the major cytotoxic effects of UV irradiation can be attributed to the cyclobutane pyrimidine dimer, as these lesions occur at 10 times the frequency of other UV-induced photoproducts in the dose range of 0.1-100 J/m2. The evidence also suggests that cyclobutane pyrimidine dimers are the major lesions responsible for induction of the SOS response and that as such they play an important, though indirect role, in the formation of mutations in irradiated DNA. Cyclobutane dimers may also be the major lesions responsible for other types of UV-light-induced mutations such as deletions. None of the available evidence rules out (6-4) photoproducts as a major premutagenic lesion induced by UV irradiation using these experimental systems. On the contrary, the mutation spectrum induced both in the lacI gene and the cI gene of phage lambda is that predicted for mutations induced by (6-4) photoproducts. The observation that neither the premutagenic lesions nor the (6-4) photoproduct is subject to enzymatic photoreactivation also implies that the (6-4) photoproducts are premutagenic. As reviewed above, neither the photosensitization experiments nor the action spectrum of the (6-4) photoproducts rules out such a role. Might a lesion other than the (6-4) photoproduct be the major premutagenic lesion responsible for point mutations in these experimental systems? It cannot be ruled out that another as yet undefined minor photoproduct that occurs with the same sequence distribution specificity as that of the (6-4) photoproduct and that is also not subject to the reactivating treatments is more mutagenic than the (6-4) photoproduct itself. Candidates for such a lesion might include a photohydrate of the (6-4) photoproduct itself or as yet undefined photoproducts. However, we believe these alternative possibilities to be remote.(ABSTRACT TRUNCATED AT 400 WORDS)
A Transverse Wavelet Transform Method For Seismic Resolution

‘ the resolution of seismic data is still in the stage being urged to be improved and exhibiting much research work to be investigated’ (Yang, F., and Qian, S., 1994). Focused on this problem, several papers have been done to solve the inverse scattering problem of seismic wave in viscoelastic media by Bleistein/Cohen (BC) method (Yang, F., and Qian, S., 1994, 1995, and 1996). And the inversion formula., both for Voight and linear media, were obtained by means of wavelet transform. The papers shown that viscosity of the media effects the resolution greatly either in theoretical analysis (Fig. 1) or in numerical computation (Fig, 2). The supposed source signature in the figures is an impulse, which shows that the viscous influence on seismic resolution is robust, and indicates a new way required to wipe out the viscous effects.
Preventing bloodstream infections: a measurable national success story in quality improvement

Over the past decade, advances in the quality of care have been slow. One area of success, however, has been in combating central line-associated bloodstream infections. Data from the Centers for Disease Control and Prevention suggest that the number of patients in US intensive care units suffering a central-line infection declined by 63 percent between 2001 and 2009. We describe the multistep process taken by many stakeholders-states, federal agencies, hospital associations, regulatory and nonprofit associations, clinicians, and local hospitals-to collaborate on the successful reduction and eradication of these infections. Having begun in Michigan, this program has spread to forty-five states, has shown sustained results in reducing hospital-associated infections and mortality, and constitutes an important measurable national success story in quality improvement and a model for improving the health and safety of Americans.
Unsteady laminar separation - An experimental study

Abstract : The design of most aerodynamic surfaces, as for example the helicopter rotor, is based essentially on quasi-steady theories. However the dynamics of a rotating blade introduce unexpected fluctuations and overshoots of properties like lift, drag, etc. The phenomenon of unsteady stall is intimately connected with the development of an oscillating boundary layer and separation. Experimental investigation of such flows was undertaken by a method of visualization developed especially for the study of laminar or turbulent boundary layers and separation. The method captures the instantaneous 2-D flow field, including regions of separated flow and provides accurate quantitative information. Laser doppler anemometer measurements complement the optically received data. Results reveal that separation responds with time-lag to external disturbances, in agreement with unsteady stall data. Oscillating outer flows result in displacement of the point of separation and under certain conditions, the Despard and Miller criterion was found to hold. Earlier theoretical models of separation are confirmed qualitatively and for the early stages of the transient phenomena. The findings provide physical insight and quantitative data that may help understand the phenomenon of unsteady stall and unsteady separation. (Author)
Circadian Variation of Susceptibility to Gastric Mucosal Injury by Acidified Aspirin or Absolute Ethanol in the Rat

Circadian rhythms of physiologic processes allow coordination of interdependent functions and separation of incompatible functions. Several gastrointestinal processes, which potentially alter the balance between gastric mucosal protection and injury, show regular fluctuations. We investigated the possibility that susceptibility to gastric mucosal injury by acidified aspirin and absolute ethanol may vary with phases of the light/dark cycle in the rat. We found that acidified aspirin caused significantly more gastric mucosal lesions when administered early in the light phase compared with administration early in the dark phase. The differences in susceptibility were not altered by pretreatment conditions such as immobilization or length of the fasting period. Absolute ethanol also caused significantly greater gastric mucosal injury when administered in the light than in the dark phase, but this difference was only evident in rats immobilized during the pretreatment fasting period. In contrast to the acidified aspirin group, rats unrestrained during pretreatment fasting did not have light/dark differences in susceptibility to ethanol injury. We concluded that rats show circadian variation in susceptibility to gastric mucosal injury by acidified aspirin.
Willingness to Pay for Broadband Access by Kentucky Farmers

Since the Internet’s inception its impact has been felt across the United States, but the distribution and adoption of the Internet has not necessarily been uniform geographically. As more consumers and businesses rely on the Internet to access information, the data transmission requirements have also increased. Consequently, access to broadband has become increasingly more important since dial-up cannot realistically handle the increased requirements. The use of broadband in agriculture can provide better access to price, weather, and management information while also opening new markets. However, many rural communities lag behind urban areas in broadband access and adoption rates. This study evaluates, through the use of a producer survey, the level of broadband Internet use, motivations for its use, degree of access to broadband, and willingness-to-pay (WTP) to fund broadband infrastructure investments. Results from the producer survey suggested farmers utilize the Internet primarily for accessing weather reports, e-mail, market reports, and agricultural news. Notably, the survey’s WTP questions allowed for the use of an interval regression to calculate producer WTP for varying demographics. The results suggested that producers who were younger, farmed larger farms, and those who currently use the Internet but do not have broadband access were WTP more in property taxes to support broadband infrastructure investments than those of a differing demographic. Because WTP levels varied drastically depending on the underlying demographics, it becomes difficult to pinpoint a WTP level for a one-time payment in property taxes that would be acceptable from a policy standpoint.
Wavelet Based Autoregressive RBF Network For Sardines Catches Forecasting

This paper deals with forecasting of monthly sardines catches in north area of Chile. The forecasting model is based on un-decimated stationary wavelet transform (SWT) combined with radial basis function (RBF) neural network and linear autoregressive (AR) model. The original monthly sardines catches data are decomposed into two sub-series employing 1-level SWT and the appropriate subseries are used as inputs to the (RBF+AR) model to forecast 1-month ahead monthly sardines catches. The forecaster's parameters are estimated by using a hybrid algorithm based on the least square (LS) method and Levenberg Marquardt (LM) algorithm. The forecasting performance based on hybrid (LS+LM) algorithm based was evaluated using determination coefficient and showed that a 99% of the explained variance was captured with a reduced parsimony and high accuracy.
Left Ventricular Cardiac Fibroma in a Child Presenting with Ventricular Tachycardia

Cardiac tumors in children are rare. Although most are histologically benign, they can be associated with life-threatening arrhythmias and sudden death. We report a 7-year-old boy, with a first episode of symptomatic tachycardia, who was found to have a left ventricular (LV) fibroma. He had a normal echocardiogram prior to an electrophysiology study, which revealed a sustained monomorphic ventricular tachycardia and a radio-opacity near the LV apex. These findings prompted a cardiac MRI, which demonstrated a discrete mass on his LV apex and free wall. Our case emphasizes that structural heart disease should be aggressively pursued in children presenting with ventricular tachycardia.
Interventional management of lower gastrointestinal bleeding

Lower gastrointestinal bleeding (LGIB) arises from a number of sources and is a significant cause of hospitalization and mortality in elderly patients. Whereas most episodes of acute LGIB resolve spontaneously with conservative management, an important subset of patients requires further diagnostic workup and therapeutic intervention. Endovascular techniques such as microcatheter embolization are now recognized as safe, effective methods for controlling LGIB that is refractory to endoscopic intervention. In addition, multidetector CT has shown the ability to identify areas of active bleeding in a non-invasive fashion, enabling more focused intervention. Given the relative strengths and weaknesses of various diagnostic and treatment modalities, a close working relationship between interventional radiologists, gastroenterologists and diagnostic radiologists is necessary for the optimal management of LGIB patients.
Urinary dehydroepiandrosterone in idiopathic hirsutism: Influence of cortisone therapy.

IN 1937 Kenyon and colleagues were unable to demonstrate a definite increase of biologically measurable urinary androgens in cases of idiopathic hirsutism (1). The following year Callow (2) observed that several women with this condition excreted moderately elevated quantities of urinary 17-ketosteroids (25–30 mg. per day), a finding since confirmed by other workers (3–5). Callow performed serial analyses on the urine of a hirsute woman with regular menses and found a variation between 16 and 26 mg. per day of 17-ketosteroids (6). When Salter and colleagues carried out digitonin alpha-beta fractionations of the urinary 17-ketosteroids of patients with this condition, 2 out of 7 patients showed slightly elevated beta fractions (7). The quantitative variation in urinary total 17-ketosteroid excretion in hirsute women was not understood to be systematic until Koets studied several such patients throughout their menstrual cycle (8) and observed a cyclic increase of urinary 17-ketosteroid excretion which appea...
Modeling Approaches to Hypersonic Aeroelasticity

The hypersonic aeroelastic problem of a double wedge airfoil typical cross-section is studied using three different unsteady aerodynamic loads: (1) third order piston theory, (2) Euler solution, and (3) unsteady Navier-Stokes aerodynamics. Computational aeroelastic response results are obtained, and compared with piston theory solutions for a variety of flight conditions. Aeroelastic behavior is studied for 7 < M < 15 at an altitude of 70,000 feet. A parametric study of offsets and wedge angles is conducted. Piston theory and Euler solutions are fairly close below the flutter boundary, and differences increase with increase in Mach number, close to the flutter boundary. Differences between viscous and inviscid aeroelastic behavior can be substantial. The results presented serve as a partial validation of the CFL3D code for the hypersonic flight regime.Copyright © 2002 by ASME
In vitro studies of the domains of the nitrogen fixation regulatory protein NIFA.

The prokaryotic enhancer-binding protein NIFA is a multidomain transcriptional activator that catalyzes the formation of open complexes at nitrogen fixation (nif) promoters by a specialized form of RNA polymerase containing sigma 54. The NIFA protein from Klebsiella pneumoniae consists of three domains: the N-terminal domain of unknown function; the central catalytic domain, which is sufficient for transcriptional activation; and the C-terminal DNA-binding domain. Purified fusion proteins between maltose-binding protein (MBP) and NIFA deleted of its N-terminal domain (MBP-delta N-NIFA) or its C-terminal domain (MBP-NIFA-delta C) activated transcription from the K. pneumoniae nifH promoter both in vitro and in vivo. We previously showed that the same was true for a fusion between MBP and the central domain of NIFA. These results indicate that NIFA is sufficiently modular for all fusions carrying its catalytic domain to be active. Unexpectedly, however, simple predictions regarding the location of determinants of the heat lability and insolubility of NIFA, which were based on previous studies of its isolated central and C-terminal domains, were not borne out. Contrary to a previous report from this laboratory, we found that the in vitro start site of transcription for the K. pneumoniae nifH operon could be either of two adjacent G residues, as others had reported in vivo. This was true independent of the activator, i.e., with MBP-NIFA and MBP-delta N-NIFA and with the homologous activator NTRC. When open complexes were formed with GTP as the activating nucleotide, the upstream G residue was probably as a consequence of initiation of transcription.
Moving Up and Moving Out: Confusing Ends and Means About Ghetto Dispersal

Assimilation is a pervasive ethos of American life. It is central to the nation's self-understanding and it is fundamental to much of American social theory and policy. See Gordon (1964), Glazer and Moynihan (1978), and Lieberson (1980). The disproportionate poverty and isolation of blacks has raised doubts about the receptive capacity of American society and has fostered a debate about the policy response required by the problem. In this paper, I argue that the assimilation model is relevant and useful to an analysis of urban black poverty. From the model, I derive a series of hypotheses that engage a long-running empirical debate over the relation between the segregated ghetto and economic opportunity. This analysis explores the relation between moving up (in socioeconomic status) and moving out (of the central-city ghetto). I argue that the call for ghetto dispersal as a means of breaking the 'underclass' stems from an incomplete understanding of ethnic group mobility within US society as well as of th...
Stage-Specific Regulation of Reprogramming to Induced Pluripotent Stem Cells by Wnt Signaling and T Cell Factor Proteins

Wnt signaling is intrinsic to mouse embryonic stem cell self-renewal. Therefore, it is surprising that reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) is not strongly enhanced by Wnt signaling. Here, we demonstrate that active Wnt signaling inhibits the early stage of reprogramming to iPSCs, whereas it is required and even stimulating during the late stage. Mechanistically, this biphasic effect of Wnt signaling is accompanied by a change in the requirement of all four of its transcriptional effectors: T cell factor 1 (Tcf1), Lef1, Tcf3, and Tcf4. For example, Tcf3 and Tcf4 are stimulatory early but inhibitory late in the reprogramming process. Accordingly, ectopic expression of Tcf3 early in reprogramming combined with its loss of function late enables efficient reprogramming in the absence of ectopic Sox2. Together, our data indicate that the stepwise process of reprogramming to iPSCs is critically dependent on the stage-specific control and action of all four Tcfs and Wnt signaling.
Rf Surface Resistance Measurements in the Pb-Bi-Sr-Ca-Cu-O System

Wires were fabricated from the high-T c superconductor Bi 0.7 Pb 0.3 SrCaCu 1.8 O x (Pb-BSCCO) by an extrusion process. The specimens were sintered for periods up to 14 days, and density was found to decrease with longer sintering times. Rf surface resistance data revealed that the onset of superconductivity occurred at 105 K and that the transition was very broad.