cssi/SciSciGPT-SciSciNet huggingface dataset:
Defective fibroblast growth factor signaling allows for nonbranching growth of the respiratory-derived fistula tract in esophageal atresia with tracheoesophageal fistula

Abstract Background/Purpose: The fistula tract in esophageal atresia with tracheoesophageal fistula (EA-TEF) appears to arise from a trifurcation of the embryonic lung bud. Subsequently, it does not branch like the other bronchi, which also arise from the lung bud. Previous results have implied that aberrant mesenchymal-epithelial signaling in the developing foregut, possibly involving fibroblast growth factors, may allow for the nonbranching growth of the fistula, and the ultimate development of the fistula tract in TEF. Methods: Adriamycin injections into pregnant rat dams induced EA-TEF formation in rat embryos. Control and Adriamycin-exposed embryos were harvested on the 13th gestational day, and the developing foregut was isolated with microdissection. mRNA was isolated from the developing fistula tract, embryonic lung, and normal embryonic esophagus. Reverse transcription-polymerase chain reaction (RT-PCR) for the IIIb splice variant of the FGF2R receptor was performed. Foregut specimens also were processed for histologic analysis, and immunofluorescence for FGF1 was performed. Results: FGF2R-IIIb is specifically absent from the developing fistula tract in TEF, whereas it is present in the normal developing lung and esophagus. FGF1 also is uniquely absent from the developing fistula tract, but it is present in the normal lung mesenchyme. Conclusions: FGF1, FGF7, and FGF10 are critical mesenchymal factors that mediate proliferation and branching morphogenesis by the developing respiratory epithelium. The absence of FGF2R-IIIb, the obligate common receptor for FGF7 and FGF10, from the fistula tract, and the absence of FGF1 in the fistula tract mesenchyme, collectively imply the absence of a specific FGF signaling pathway in the developing fistula tract. This absence of FGF signaling could explain the lack of branching by the developing fistula tract as it grows caudally in the abnormally developing embryo. Downregulation of these components of the FGF signaling pathways may allow for a patterned compensation by the embryo for the proximal foregut atresia in this anomaly. This compensation may then reestablish gastrointestinal continuity as the fistula tract connects to the developing stomach. J Pediatr Surg 35:1421-1425. Copyright © 2000 by W.B. Saunders Company.
Homozygosity of the d3-growth hormone receptor polymorphism is associated with a high total effect of GH on growth and a low BMI in girls with Turner syndrome.

Summary Objective The protein polymorphism of the GH receptor caused by genomic deletion of exon 3 (d3) has been linked to the magnitude of the first-year-growth response to GH in girls with Turner syndrome. Here, we studied the long-term effect of GH therapy in Turner syndrome in correlation to this polymorphism. Design The study was mainly retrospective. Patients The women with Turner syndrome (n = 48) had been treated with GH over the past 18 years at our hospital. The mean GH dose used was 38 µg/kg/day (SD 8). Measurements The GHR-exon 3 locus was genotyped using a PCR multiplex assay for both alleles and a second PCR assay for the full length (fl) allele only. Results The fl/fl, d3/fl and d3/d3 genotypes were present in 24, 17 and 7 women, respectively. Mean Turner height standard deviation scores (SDS) at start of therapy was 0·09 (1·09), mean age was 9·1 years (3). Age, height, target height, age at start of puberty and mode of GH therapy were not different between the groups. Total gain in height (difference between final adult height and initial height) was significantly higher in the d3/d3 group [+1·84 SDS (0·31)] than in the fl/fl group [+0·72 SDS (0·92)] and in the d3/fl group [+0·83 SDS (0·93)] (P < 0·001). A covariance analysis confirmed the effect of the polymorphism. Mean BMI SDS at the start and end of therapy was low in the d3/d3 group and significantly lower than in the fl/fl group (P < 0·04). Conclusions Our data suggest that homozygosity for the d3-GHR polymorphism is associated with a unique GH responsiveness and a weight regulation towards a lower BMI in girls with Turner syndrome.
Short chain fatty acids induce TH gene expression via ERK-dependent phosphorylation of CREB protein

Butyrate modulates specific gene expression through various second-messenger signal transduction systems including activation of the PKA/cAMP pathway (Decastro, M., Nankova, B.B., Shah, P., Patel, P., Mally, P.V., Mishra, R., La Gamma, E.F., 2005. Short chain fatty acids regulate tyrosine hydroxylase gene expression through a cAMP-dependent signaling pathway, Brain Res. Mol. Brain Res. 142 28-38; Mally, P., Mishra, R., Gandhi, S., Decastro, M.H., Nankova, B.B., Lagamma, E.F., 2004. Stereospecific regulation of tyrosine hydroxylase and proenkephalin genes by short-chain fatty acids in rat PC12 cells, Pediatr. Res. 55 847-854). In the current report, we provide additional evidence that exposure to butyrate causes a rapid activation of the MAP kinase pathway, associated with increased phosphorylation of CREB. Under these conditions, no changes in relative amounts of CREB protein were observed by Western blot. Pre-treatment with the MAPK specific inhibitor (U0126) or the adenylate cyclase inhibitor dideoxyadenosine (ddA) abolished the butyrate-induced: (i) accumulation of TH mRNA, (ii) the phosphorylation of ERK1/2 as well as (iii) CREB phosphorylation. PC12 cells transfected with a TH promoter-luciferase reporter gene showed a robust induction in response to butyrate that was significantly reduced after co-transfection of either of two dominant-negative CREB expression vectors. Nuclear run-on assays demonstrated that butyrate increases endogenous TH gene transcription. We conclude that the initial steps of butyrate-induced gene activation are mediated through the CREB/CREB family of transcription factors which are coupled to both the MAP kinase and cAMP-dependent second messenger systems. Our data delineate a molecular mechanism through which short chain fatty acid's, their related drug-congeners (e.g., valproate) or even diet-derived butyrate (from fermentation of carbohydrates in the gut) can in principle, modulate brain catecholaminergic systems by modifying TH gene expression, dopaminergic levels and the corresponding animal behavior. These molecular relationships also offer a plausible explanation of how the well-recognized clinical effects of ketogenic diets can alter human behavior via the same central mechanisms.
A capacity allocation problem with integer side constraints

We address a capacity allocation problem arising as a subproblem of an artificial intelligence-based scheduling system for a semiconductor wafer fabrication facility. Tooling constraints, setup considerations and differences in machine capabilities are taken into account. Focusing on the objectives of maximizing throughput and minimizing deviation from predetermined production goals, we formulate the problem as a maximum flow problem on a bipartite network with integer side constraints and develop efficient heuristics which obtain near-optimal solutions in negligible computation time. The type of network flow problem we study has not been addressed in the literature to date and is of considerable theoretical interest. From a practical point of view, the network flow model of the problem and the algorithms developed for its solution are applicable to a wide range of production settings.
VR assisted surgery planning

We are developing a system called the virtual reality assisted surgery program (VRASP) for implementation in the hospital operating room (OR). VRASP will give the surgeon flexible intraoperatively computational support. It will permit modification and control of very large scan data sets in real time. It will render and transmit virtual imagery in response to the surgeon's commands without interfering with normal surgical activities. And it will register the displayed imagery simultaneously with respect to the surgeon and the patient, without perceptible computing or display lag. VRASP is being developed specifically to assist surgeons during craniofacial, neurologic, orthopedic, thoracic, and urologic surgery. VRASP will enable surgeons to interactively visualize 3D renderings of CT and MRI data with hands-free manipulation of the virtual display. The surgeon will be able to scale, orient, and position prescanned body imagery on-line in real time from any desired perspective. The clinical goal is dynamic fusing of 3D body scan data with the actual patient in the OR. The customized interface will permit ready on-line access to the preoperative plan and to update measurement and analysis based on the real time OR data.
On the dynamics of nondegenerate polynomial endomorphisms of C2

Abstract We generalize the Brolin-Lyubich theorem for nondegenerate polynomial endomorphisms of C 2. We prove, for a nondegenerate polynomial endomorphism p with the hyperbolic restriction to the line at infinity, that its canonical invariant current ωp is a complex cycle near the line at infinity in the sense of Sullivan (Invent. Math.36 (1976), 225–255).
A new gaseous signaling molecule emerges: Cardioprotective role of hydrogen sulfide

Cardiovascular (CV) research has largely been focused on two endogenously produced gaseous signaling molecules, namely, nitric oxide (NO) and carbon monoxide (CO). These gaseous messengers are both highly conserved evolutionarily and synthesized by endogenous enzyme systems. Extensive research efforts have uniformly demonstrated that CO- and NO-based therapeutics protect the brain, heart, and circulation against a number of CV disease states (1–3). However, controversy exists regarding the therapeutic value of both CO and NO, with some studies citing NO cytotoxicity at very high levels and under certain conditions (2). The toxic effects of NO are related to the highly reactive nature of NO and its interaction with superoxide to form the potent oxidant peroxynitrite (ONOO−) (2). Very recently, a third endogenously produced gaseous signaling molecule, hydrogen sulfide (H2S), has emerged as a potentially important mediator of CV homeo stasis and cytoprotection (3). In this issue of PNAS, Benavides et al. (4) reveal that the vasculoprotective and antihypertensive effects of dietary garlic (Allium sativum) are mediated in large part via the generation of H2S.
An enzymatic method for the hydrolysis of urinary 1-naphthyl glucuronide.

Capillary gas chromatography was performed with a Perkin Elmer 8320 instrument in the splitless mode and by using flame ionization detection. The bonded OV-17 fused silica column was 25 m by 0.25 mm i.d. The oven temperature program was: hold 100 ~ for 1.5 min, i00 ~ to 240 ~ at 30~ hold 240 ~ for 5 min. The solvent was vented after a 0.7 min hold. The septa were changed daily and the injection port liner was cleaned and silylanized weekly. This treatment was supplemented by daily injections of I0 ~L of silylating solution. The silylating solution was obtained from Supelco, Inc., Bellefonte, PA, No. 3-3065 . C18 SepPaks were obtained from Waters Assoc., Medford, MA. The ~-glucuronidase (G-0751, partially purified powder from Helix pomatia) and a-naphthyl-~-D-glucuroniC acid sodium salt (N-8378) were obtained from Sigma Chemical Co., St. Louis, MO.
Allelic variants in HOX genes in cryptorchidism.

BACKGROUND:Cryptorchidism is one of the most common congenital anomalies and is associated with increased risk for infertility and testicular cancer later in life. Findings from animal models and small clinical studies suggest that the posterior HOX genes (paralogs 9–13) could be potential candidate genes for cryptorchidism and that the HOX genes are functionally redundant within paralogous groups. METHODS: The coding regions and exon-intron boundaries of the 16 posterior HOX genes were sequenced and analyzed in group 1 (44 nonsyndromic cryptorchidism cases and 46 healthy controls). Those specific variants found to be significantly different between cases and controls in group 1 were examined in DNA from group 2 (108 cases and 114 controls). RESULTS: A total of 57 variants was found in group 1, among which the allele frequency of 180A>G (A60A) in HOXD13 alone was significantly elevated in cases versus controls (P = 0.02). In the combined 1 + 2 group, cases were also more likely than controls to have the G allele (P = 0.002). As predicted by an exonic splicing enhancer finder program, the 180A>G (A60A) variant is expected to have an influence on the splicing of transcripts from HOXD13. In group 1, case subjects were more likely to carry multiple variants in HOXA13 and HOXD13 (P = 0.02) than controls. CONCLUSIONS: The variant 180A>G (A60A) in HOXD13 is a risk factor for cryptorchidism, and a dynamic equilibrium of genes in HOX paralog 13 is involved in the pathogenesis of cryptorchidism. Birth Defects Research (Part A), 2007. © 2006 Wiley-Liss, Inc.
An empirical analysis of White privilege, social position and health

Accumulated evidence has demonstrated that social position matters for health. Those with greater socioeconomic resources and greater perceived standing in the social hierarchy have better health than those with fewer resources and lower perceived standing. Race is another salient axis by which health is stratified in the U.S., but few studies have examined the benefit of White privilege. In this paper, we investigated how perceptions of inequality and subjective and objective social status affected the health and well-being of N = 630 White residents in three Boston neighborhoods lying on a social gradient differentiated by race, ethnicity, income and prestige. Outcomes were self-rated health, dental health, and happiness. Results suggested that: neighborhood residence was not associated with health after controlling for individual level factors (e.g., positive ratings of the neighborhood, education level); objective measures of socioeconomic status were associated with better self-reported and dental health, but subjective assessments of social position were more strongly associated; and White residents living in the two wealthiest neighborhoods, and who perceived Black families as welcome in their neighborhoods enjoyed better health than those who believed them to be less welcome. However, those who lived in the least wealthy and most diverse neighborhood fared worse when reporting Black families to be welcome. These results suggest that White privilege and relative social position interact to shape health outcomes.
Mit strategischem Controlling gezielt den IT-Wertbeitrag verbessern

Ein effektives, effizientes und insbesondere strategisches IT-Controlling ist fur die Ermittlung und Steuerung des IT-Wertbeitrags unabdingbar. Nichtsdestotrotz zeigt sich bei der Analyse des strategischen IT-Controllings in der Praxis deutscher Unternehmen ein verbesserungswurdiges Bild. Ein strategischer IT-Controlling-Ansatz sollte neben der Schaffung von Kostentransparenz vor allem die Ermittlung zusatzlicher Effizienz-/Effektivitats- und Leistungskennzahlen berucksichtigen, um darauf basierend gezielte Verbesserungsmasnahmen identifizieren und umsetzen zu konnen. Fur viele Unternehmen stellt dies eine grose Herausforderung dar, so dass die Umsetzung eines solchen Ansatzes in der Praxis ausreichend Beachtung finden sollte. Der Beitrag zeigt, welchen Anforderungen ein strategisches IT-Controlling-Modell genugen muss und welche Aufgaben zu bewaltigen sind. Daruber hinaus wird anhand eines Fallbeispiels dargestellt, wie die Umsetzung strategischer IT-Controlling-Ansatze in der Praxis erfolgen kann.
Deuterated scintillators and their application to neutron spectroscopy

Abstract Deuterated scintillators have been used as a tool for neutron spectroscopy without Neutron Time-of-Flight (n-ToF) for more than 30 years. This article will provide a brief historical overview of the technique and current uses of deuterated scintillators in the UM-DSA and DESCANT arrays. Pulse-shape discrimination and spectrum unfolding with the maximum-likelihood expectation maximization algorithm will be discussed. Experimental unfolding and cross section results from measurements of (d,n), ( 3 He,n) and (α,n) reactions are shown.
Log-log convexity and backward uniqueness

We study backward uniqueness properties for equations of the form u' + Au = f. Under mild regularity assumptions on A and f, it is shown that u(0) = 0 implies u(t) = 0 for t < 0. The argument is based on α-log and log-log convexity. The results apply to mildly nonlinear parabolic equations and systems with rough coefficients and the 2D Navier-Stokes system.
Ambient Air Concentrations of Pesticides in California

The California Air Resources Board conducted ambient air monitoring of pesticides in support of the California Department of Pesticide Regulation toxic air contaminant program. Monitoring was done in several communities in a county of high use during the month of expected peak use of a particular pesticide in order to assess general population exposure. Additional sampling was conducted adjacent to specific agricultural applications to assess maximum short-term concentrations to which the public might be exposed. Medium and low volume samplers were used with appropriate collection media (e.g., Teflon filters, XAD-2 adsorbent resin), followed by laboratory analysis. Concentrations measured around specific applications would be expected to be representative of other areas, especially in California, with comparable application rates, crops, and weather conditions. Since the program began in 1986, monitoring has been conducted for 22 pesticides. Results for three soil fumigants were of potential public health...
On macroscopic dimension of rationally inessential manifolds

We show that, for a rationally inessential orientable closed n-manifold M whose fundamental group is a duality group, the macroscopic dimension of its universal cover $$\tilde M$$ is strictly less than n: dim MC $$\tilde M < n$$ . As a corollary, we obtain the following partial result towards Gromov’s conjecture The inequality dim MC $$\tilde M < n$$ holds for the universal cover $$\tilde M$$ of a closed spin n-manifold M with a positive scalar curvature metric if the fundamental group π 1 (M) is a duality group satisfying the analytic Novikov conjecture.
cDNA and protein sequence for canine arachidonate 5‐lipoxygenase: stuctural modelling and species differences

5-lipoxygense is an important enzyme in the genesis of leukotrienes through arachidonic acid metabolism to 5-hydroxyecosatetranoic acid (5)-HETE. Not only is this enzyme important in producing the chemotactic leukotrienes, but it may also be important in producing autocrine lipid signaling molecules (5-oxo-ETE, LTB4) for cellular proliferation. mRNA was isolated in our laboratory from canine leukocytes, and transitional carcinoma cells using the Qiagen whole blood mRNA extraction kit. An internal cDNA fragment was cloned using primers designed according to homologous regions in human and rat 5-LOX. Once an internal sequence was determined both 5′ and 3’ RACE reactions were performed according to the manufacturer's suggestions using the Ambion RACE kit. The 5′ region just upstream of the ATG start site to 300 bp beyond the terminal codon was sequenced. Protein structural modeling was performed through threading of the presumed sequence onto the known rabbit 15-LOX using Swiss PDB viewer. Based on the known human sequence and structural modeling there are three areas of interest in the canine structure. (i) In the catalytic domain there are a number of charged amino acid differences in an external alpha helix at amino acids 645-660, which may confer structural differences between human and canine 5-LOX. (ii) An important phosphorylation site at ser 532 is actually a threonine in canine 5-LOX. (iii) All mammalian 5-lipoxygense enzymes are between 673–674 amino acids; however, the canine 5-LOX sequence contains two additional amino acids, a leucine and valine at residues 379 and 380 respectively, making canine 5-LOX 676 amino acids rather than the 674 identified in human, mouse and bovine.
Apparatus for studying ultrasmall contacts

On-chip IC dimensions have been scaled down without a corresponding decrease in the size of off-chip interconnects, including pressure contacts. As the number of I/O lines increases, pressure contacts need to operate at low forces. The use of scanning tunneling microscope/atomic force microscope (STM/AFM) technology (treating an STM tip-sample junction either as a model for an ultrasmall contact per se, or a microscopic element of a larger contact) is investigated. A combined AFM/STM has been built to allow electrical characterization of contacts under a range of forces and tip and substrate materials. The contact force can be varied from 10/sup -6/ to 10/sup -9/ N, and contact dimensions (as determined by SEM) are approximately 100-nm in diameter. Initial results demonstrate that the reversibility of a contact depends on the hardness of the contact materials. >
Quasi-Dynamic Urban-Location Models with Endogenously Determined Travel Costs

A quasi-dynamic model of residential and job location is fused with the equilibrium trip-assignment model in the manner suggested by the combined model of trip distribution and assignment. The implications of this combined model for assumptions about future levels of interaction are examined. Extensions of the model to include explicit housing stocks and prices and the determination of residential- and job-location attractiveness are considered.
Occurrence of angiographic femoral artery complications after vascular closure with Mynx and AngioSeal

Introduction There have been recent reports of high vascular complication rates after the use of the Mynx vascular closure device (VCD). At our institution, vascular complications due to these devices have rarely been encountered. A study was undertaken to retrospectively compare angiographic abnormalities seen after femoral artery closure by both the Mynx and AngioSeal VCDs to provide further insight into the risks associated with VCDs. Methods All adult patients who underwent deployment of either a Mynx or AngioSeal VCD and subsequently underwent repeat angiography within the next 30 days between 1 July 2010 and 1 April 2011 were reviewed. Two independent blinded radiologists compared blinded pre-procedure and follow-up femoral angiograms for the presence of pseudoaneurysm or other vascular abnormality. Hospital records were reviewed for major or minor complications of the groin site or femoral artery. Results Thirty patients (31 angiograms) underwent vascular closure with a Mynx and 57 patients (69 angiograms) received an AngioSeal. The average time elapse until repeat femoral angiography was 6.2 days (range 1–21, median 5.5 days) in the Mynx group and 6.3 days (range 0–30, median 5 days) in the AngioSeal group. Two pseudoaneurysms and one minor stenosis were identified in the AngioSeal group. No angiographic abnormalities were seen in the Mynx group. No intraluminal filling defects were demonstrated on any of the follow-up femoral angiograms. One patient who received an AngioSeal developed a delayed minor groin site hematoma that did not require surgical intervention. Conclusions Angiographic complications were seen in only 3% of patients after closure with Mynx or AngioSeal VCDs. There were no clinically significant groin site or vascular complications. These data suggest that both VCDs are safe for use after angiography with a low rate of femoral artery complications.
Late-Holocene climate and ecosystem history from Chesapeake Bay sediment cores, USA

Palaeoclimate records from late-Holocene sediments in Chesapeake Bay, the largest estuary in the USA, provide evidence that both decadal to centennial climate variability and European colonization ...
The clathrin adaptor complexes as a paradigm for membrane-associated allostery.

The clathrin-associated adaptor protein (AP) complexes AP-1 and AP-2 are two members of a family of heterotetrameric assemblies that connect transmembrane protein cargo to vesicular coats. Cargo binding by AP-1 is activated by the small GTPase Arf1, while AP-2 is activated by the phosphoinositide PI(4,5)P2. The structures of both AP-1 and AP-2 have been determined in their locked and unlocked conformations. The structures show how different activators use different mechanisms to trigger similar large scale conformational rearrangements. The details of these mechanisms show how membrane docking and allosteric activation of AP complexes are intimately connected.
Comparison of acute hemodynamic response to dobutamine and intravenous MDL 17,043 (enoximone) in severe congestive heart failure secondary to ischemic cardiomyopathy or idiopathic dilated cardiomyopathy.

Abstract The acute hemodynamic response to intravenous dobutamine administration was compared with intravenous MDL 17,043 administration in 8 patients with severe, chronic congestive heart failure. Simultaneous radionuclide angiography was performed with gated equilibrium blood pool imaging to derive left ventricular volumes and ejection fraction during serial hemodynamic measurements. Six patients had an optimal dobutamine dose of 10 μg/kg/min; 2 others were compared at a dose of 7.5 μg/kg/ min; comparisons with MDL 17,043 were after a 1.5-mg/kg bolus dose in all 8 patients. Dobutamine and MDL 17,043 caused significant and similar increases in cardiac index and stroke volume index. Dobutamine significantly increased heart rate and MDL 17,043 did not. MDL 17,043 significantly decreased pulmonary artery wedge, mean pulmonary artery and right atrial pressures; dobutamine did not. Dobutamine increased end-diastolic volume in 4 patients, with little concomitant decrease in wedge pressure; MDL 17,043 caused no change or a decrease in left ventricular end-diastolic volume in 5 patients, but consistently decreased wedge pressure in all. Thus, the left ventricular pressure-volume curve was displaced downward to a more favorable position after MDL 17,043 but not after dobutamine. In patients with chronic congestive heart failure, acute myocardial performance was more optimally influenced by MDL 17,043 than dobutamine administration.
Energy Flow in the Information Technology Stack: Introducing the Coefficient of Performance of the Ensemble

The information technology industry is in the midst of a transformation to lower the cost of operation through consolidation and better utilization of critical data center resources. Successful consolidation necessitates increasing utilization of capital intensive "always-on" data center infrastructure, and reducing the recurring cost of power. A need exists, therefore for an end to end physical model that can be used to design and manage dense data centers and determine the cost of operating a data center. The chip core to the cooling tower model must capture the power levels and thermo-fluids behavior of chips, systems, aggregation of systems in racks, rows of racks, room flow distribution, air conditioning equipment, hydronics, vapor compression systems, pumps and heat exchangers. Earlier work has outlined the foundation for creation of a "smart" data center through use of flexible cooling resources and a distributed sensing and control system that can provision the cooling resources based on the need. This paper shows a common thermodynamic platform which serves as an evaluation and basis for policy based control engine for such a "smart" data center with much broader reach - from chip core to the cooling tower. Computational Fluid Dynamics modeling is performed to determine the computer room air conditioning utilization for a given distribution of heat load and cooling resources in a production data center. Coefficient of performance (COP) of the computer room air conditioning units, based on the level of utilization, is used with COP of other cooling resources in the stack to determine the COP of the ensemble. The ensemble COP represents an overall measure of the performance of the heat removal stack in a data center.Copyright © 2006 by ASME
Strategic Planning for Information Resources: The Evolution of Concepts and Practice

The evolution of planning for information systems is reviewed in terms of practice and underlying concepts. Current trends in IS planning are identified and evaluated based on the evolution that has taken place through three eras of IS planning.
Enzymes of nucleotide synthesis

Seven new structures reported during the past year have increased dramatically our understanding of enzymes involved in nucleotide de novo synthesis and salvage. Several new protein folds have been identified, including at least four prototypes for new functional families. The construction of larger structures from modules with a catalytic function is a recurring theme. Our understanding of the structural basis of allostery will be enriched by the three new structures of allosteric enzymes.
Quantitative FTIR Determination of Extinction Coefficients of Adsorbed CO

A combined IR and MS technique was used to determine extinction coefficients of adsorbed CO on the 4% Rh/SiO2 catalyst. An isotopic exchange experiment has been made to obtain accurate integrated absorption intensities. The experimental procedure provides a fast and accurate, as well as a highly reproducible, method for the determination of extinction coefficients of adsorbed surface species. Integrated absorption intensities for Rh+(12CO) and Rh+(13CO)2 were determined at 373 K and 0.1 MPa to be 1.35 and 8.02 cm/μmol, respectively.
Carbyne thermochemistry from energy-resolved collision-induced dissociation

The 298 K heats of formation of the carbynes CH, CF, and CCl have been determined from measurements of the chloride dissociation energies of the halocarbene anions, CHCl·−, CFCl·−, and CCl2·−. The chloride dissociation enthalpies were measured by energy-resolved collision-induced dissociation in a flowing afterglow—triple quadrupole instrument to be 37.7 ± 2.3, 21.9 ± 1.1, and 33.4 ± 2.3 kcal/mol, for CHCl·−, CFCl·−, and CCl2·−, respectively. The dissociation enthalpies were combined with the known heats of formation and electron affinities of the corresponding halocarbenes and other thermochemical data to give: ΔHf,298(CH) = 142.2 ± 3.2, ΔHf,298(CF) = 60.6 ± 3.4, and ΔHf,298(CCl) = 105.9 ± 3.1 kcal/mol. The experimental results for all three carbynes are in good agreement with the predicted heats of formation obtained from G2 calculations. The measured values for CH and CF are in excellent agreement with other experimental values, whereas results for CCl do not support the heats of formation for this carbyne given in current thermochemical data compilations. The halogen substituent effects on carbyne stabilities and on the sequential C–H bond energies of CH3F and CH3Cl are shown to be dominated by π-donor interactions.
The evolution of young silicic lavas at Medicine Lake Volcano, California: Implications for the origin of compositional gaps in calc-alkaline series lavas

At Medicine Lake Volcano, California, the compositional gap between andesite (57–62 wt.% SiO2) and rhyolite (73–74 wt.% SiO2) has been generated by fractional crystallization. Assimilation of silicic crust has also occurred along with fractionation. Two varieties of inclusions found in Holocene rhyolite flows, hornblende gabbros and aphyric andesites, provide information on the crystallization path followed by lavas parental to the rhyolite. The hornblende gabbros are magmatic cumulate residues and their mineral assemblages are preserved evidence of the phases that crystallized from an andesitic precursor lava to generate the rhyolite lavas. The andesitic inclusions represent samples of a parental andesite and record the early part of the differentiation history. Olivine, plagioclase and augite crystallization begins the differentiation history, followed by the disappearance of olivine and augite through reaction with the liquid to form orthopyroxene and amphibole. Further crystallization of the assemblage plagioclase, amphibole, orthopyroxene, magnetite, and apatite from a high-SiO2 andesite leads to rhyolite. This final crystallization process occurs on a cotectic that is nearly horizontal in temperature-composition space. Since a large amount of crystallization occurs over a limited temperature interval, a compositional gap develops between rhyolite and high SiO2 andesite. Liquidus surfaces with shallow slopes in temperature-composition space are characteristic of several late-stage crystallization assemblages in the andesite to rhyolite compositional range. Experimentally produced plagioclase+ amphibole+orthopyroxene+magnetite and plagioclase+ augite+low-Ca pyroxene+magnetite cotectics have liquidus slopes that are nearly flat. At other calc-alkaline volcanic centers crystallization processes involving large compositional changes over small temperature intervals may also be important in the development of bimodal volcanism (i.e. the existence of a composition gap). At Mt. Mazama and Mt. St. Helens, USA and Aso Caldera and Shikotsu, Japan the amphibole-bearing assemblage was important. At Krakatau, Indonesia and Katmai, USA, an augite+orthopyroxene-bearing assemblage was important. In addition to its role in the production of a compositional gap between intermediate and rhyolitic lavas, the crystallization process increases the H2O content of the residual liquid. This rapid increase in residual liquid volatile content which results from the precipitation of a large proportion of crystalline solids may be an important factor among several that lead to explosive silicic eruptions.
A chromatic explosion: the development and future of multiparameter flow cytometry

Multiparameter flow cytometry has matured tremendously since the 1990s, giving rise to a technology that allows us to study the immune system in unprecedented detail. In this article, we review the development of hardware, reagents, and data analysis tools for multiparameter flow cytometry and discuss future advances in the field. Finally, we highlight new applications that use this technology to reveal previously unappreciated aspects of cell biology and immunity.
Temperature-dependent absorption cross-sections in the thermal infrared bands of SF5CF3

Abstract Absorption cross-sections have been measured at five temperatures between 213 and 323 K in the infrared bands of SF5CF3. The spectra were recorded at a resolution of 0.112 cm −1 using a commercial Fourier transform infrared spectrometer and a 20 cm temperature-controlled sample cell. Samples of SF5CF3 were pressurized with high-purity nitrogen to a total pressure of 1013.3 hPa (760 Torr ) . Six or more spectra with varying SF5CF3 column amounts were analyzed at each temperature. The full spectral range of the measurements was 520– 6500 cm −1 , with only weak bands observed beyond 1400 cm −1 . Absorption of thermal radiation in the 8– 12 μm atmospheric window region being important for climate change, we report here the integrated cross-sections of the significant absorption bands in that spectral region. Our results closely match room temperature values reported previously. Only small variation of the integrated absorption cross-sections with temperature was found. Our results confirm the accuracy of the previous measurements, which find SF5CF3 important for global climate change on a per molecule basis. Absorption cross-sections derived from a single, near Doppler-limited spectrum recorded at room temperature do not show any rotational fine structure in the 700– 950 cm −1 region.
Can donations reduce a donor's welfare?

Weisbrod has argued that if government provides some public good, unsatisfied high demanders will make themselves better off by voluntarily providing this public good. This essay shows that this claim is not necessarily true if the levels of governmental and voluntary provision are determined simultaneously. In such a setting, a high demander may be worse off compared to the situation in which the government alone provides the public good.
Examining the effects of coping and social support on work and life stress among police officers

Abstract This study examined the effects of coping and social support on psychological distress in response to stressful work and life events among police officers. As part of a larger study investigating stress and coping, a sample of 233 police officers employed within a mid-sized northeastern law enforcement organization volunteered for this study. The results of hierarchical multiple regression analysis showed that the main effect of life events was related to higher distress. Problem-focused coping resulted in a “reverse buffering effect”; the relationship between work events and distress was associated with higher distress. Seeking social support buffered the relationship between work events and distress, and emotion-focused coping buffered the relationship between life events and distress. The implications for developing and implementing stress management programs for police officers are discussed.
Experimental characterization of Fresnel zone plate for hard x-ray applications

A series of experimental measurements was conducted for the characterization of a transmission circular zone plate. The zone plate (ZP), with a primary focal length of 40 cm for 8 keV photons, was illuminated by monochromatized synchrotron x rays. Focusing efficiency of the ZP was measured as a function of x-ray energy between 5 - 1 keV, from which the ZP thickness was determined. Focal spot sizes at the first, second, and third order focus were measured, and they agreed very well with the calculated values. Images of a 1000 mesh/inch gold grid were also obtained at the three focal planes. The grid scans indicated that the spatial resolution is about 2 (mu) in the image obtained at the third order focus.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
An Experimental Investigation of Explanations for Outcome Effects on Appraisals of Capital‐Budgeting Decisions*

. Studies investigating effects of outcomes on judgments and decisions have been increasing within the business/accounting research literatures. No study, however, has addressed the presence or absence of such effects in terms of potential explanations and the conditions affecting their viability. Three such explanations are the foci of the present study: cognitive reconstruction, self-enhancing motive, and an escalation-of-commitment analogue. The viability of these explanations was investigated experimentally in an accounting context in which subjects evaluated a capital-budgeting committee's funding priority decisions with or without project outcome information (five-year operating results). Experimental results fully support the cognitive reconstruction explanation for outcome effects on decision appraisals but provide only limited support for the self-enhancing motive and escalation-of-commitment explanations. Results of additional experimentation are presented, further supporting logic inherent in the hypothesis derived from the cognitive reconstruction explanation. The relationship of the present study to prior research and implications for future research and practice are discussed. Resume. Les etudes portant sur l'analyse de l'incidence de l'issue d'une situation sur les jugements poses et les decisions prises par la suite se sont multipliees dans la recherche en gestion et en comptabilite. Aucun chercheur ne s'est pourtant penche sur la presence ou l'absence d'une telle incidence en s'interrogeant sur son explication potentielle et sur les facteurs qui influent sur sa viabilite. La presente etude s'articule autour de trois de ces explications: la reconstruction cognitive, la promotion personnelle et un equivalent de l'escalade de l'engagement. La viabilite de ces explications a ete soumise a une etude experimentale dans un contexte comptable dans lequel les sujets evaluaient les decisions d'un comite charge du choix des investissements dans le cadre de l'etablissement des priorites en matiere d'affectation des fonds, avec ou sans information sur l'issue des projets (resultats d'exploitation de cinq ans). Les resultats de l'experience confirment sans equivoque l'explication de la reconstruction cognitive relativement a l'incidence de l'issue des projets sur les evaluations decisionnelles, mais ils n'appuient que de facon mitigee les explications de la promotion personnelle et de l'escalade des engagements. Les auteurs exposent les resultats d'autres experiences, qui viennent etayer la logique sous-jacente a l'hypothese fondee sur l'explication de la reconstruction cognitive. Ils analysent enfin la relation entre la presente etude et les travaux de recherche anterieurs de meme que ses consequences eventuelles sur la recherche et la profession.
Sexual devolution in plants: apomixis uncloaked?

There are a growing number of examples where naturally occurring mutations disrupt an established physiological or developmental pathway to yield a new condition that is evolutionary favored. Asexual reproduction by seed in plants, or apomixis, occurs in a diversity of taxa and has evolved from sexual ancestors. One form of apomixis, diplospory, is a multi-step development process that is initiated when meiosis is altered to produce an unreduced rather than a reduced egg cell. Subsequent parthenogenetic development of the unreduced egg yields genetically maternal progeny. While it has long been apparent from cytological data that meiosis in apomicts was malfunctional or completely bypassed, the genetic basis of the phenomenon has been a long-standing mystery. New data from genetic analysis of Arabidopsis mutants1 in combination with more sophisticated molecular understanding of meiosis in plants indicate that a weak mutation of the gene SWI, called DYAD, interferes with sister chromatid cohesion in meiosis I, causes synapsis to fail in female meiosis and yields two unreduced cells. The new work shows that a low percentage of DYAD ovules produce functional unreduced egg cells (2n) that can be fertilized by haploid pollen (1n) to give rise to triploid (3n) progeny. While the DYAD mutants differ in some aspects from naturally occurring apomicts, the work establishes that mutation to a single gene can effectively initiate apomictic development and, furthermore, focuses efforts to isolate apomixis genes on a narrowed set of developmental events. Profitable manipulation of meiosis and recombination in agronomically important crops may be on the horizon. BioEssays 30:798–801, 2008. © 2008 Wiley Periodicals, Inc.
Social provisions of real and imaginary relationships in early childhood.

Preschool-aged children's perceptions of their social relationships were examined, including those with parents, best friends, siblings, and imaginary companions. Sixty 4-year-old children participated in an interview designed to measure perceptions of the degree of conflict, nurturance, instrumental help, and power available in their relationships. Three groups were compared: children with (a) invisible friends, (b) companions who were personified objects (e.g., dolls), and (c) no imaginary companion. Results indicated that children differentiated the relationships in their social networks according to provisions. Parent-child relationships afforded instrumental help and siblings were associated with conflict. Provisions of real and imaginary friendships were similar, although imaginary friends were preferred as objects of nurturance. Results imply that 4-year-old children have developed differentiated relationship schemas and that those of children with invisible friends may be particularly distinct.
Heat transfer through the unsteady laminar boundary layer on a semi-infinite flat plate Part I: Theoretical considerations

Abstract The problem of a semi-infinite plate moving with a velocity uw(t) into a stagnant fluid is considered, and a solution correct to second order for heat transfer with constant surface enthalpy is obtained for small ξ = x/∫toue(t) dt (where t is time, u e (t) = t u w (t) and x is the distance from the leading edge). The solution, which includes the effect of viscous dissipation, is valid under the conditions that ue(t) > 0 and ue(t) is infinitely differentiate for all t, and is the continuation of the work of Cheng and Elliott, who obtained the solution to the incompressible momentum equation for the velocity profile and skin friction. Second order results were obtained by numerical integration for a Prandtl number of 0.72, and satisfactory agreement is shown with the results of other investigators who used different approaches in obtaining just the first order solution, or an incomplete second order solution.
Museums and Funders Embracing New Constituencies

Abstract The census data of 1990 served as a wakeup call for the leaders of cultural institutions across the nation. The 1990 census indicated that minorities were growing at a rate greater than that of the nonminority population; and Latinos were the fastest growing group in the nation. Museum management teams were forced to come to terms with changing demographic realities. Some museums were sited in communities that had once been affluent, but were now populated by the poor and/or working classes. Others were acknowledging a decline in visitation as the competition for the leisure time of local citizens became more intense due to the creation of new for-profit and nonprofit venues offering entertainment and educational opportunities. Many museum leaders were forced to acknowledge that their collections, exhibitions, and programs were shaped by a group of individuals who were no longer active stakeholders and who did not support the institution in sufficient number. Additionally, local residents often s...
Performance by normal subjects on the Shipley Institute of Living Scale

The usefulness of the Shipley Institute for Living Scale is limited by the lack of norms on middle-aged and older adults. This study reports data from 254 normal subjects aged 20 to 29 to 50 and older.
Magnesium deficiency and blood 2,3-diphosphoglycerate concentrations in sedentary and exercised male Osborne-Mendel rats.

Abstract Magnesium deficiency lowers endurance capacity of untrained rats by an as yet unknown mechanism. We tested the hypothesis that low plasma and blood Mg concentrations would reduce blood 2,3-diphosphoglycerate (2,3-DPG) concentrations, thus diminishing the oxygen delivery system of the Mg-deficient rat. Untrained male Osborne-Mendel rats (95 g) were studied at rest or following exhaustive exercise after three weeks of dietary treatment (400 or 100 μg Mg/g diet; deionized or high Mg water [>85 μg Mg/ml]). Magnesium deficiency resulted in lowered plasma and red blood cell (RBC) Mg concentrations and reduced endurance capacity compared with controls. Magnesium supplementation normalized these parameters. 2,3-DPG was elevated by 10% in rats acutely exercised compared with sedentary rats; however, 2,3-DPG levels were not affected by dietary Mg intake. Acute exercise tended to increase erythrocyte Mg concentrations in control rats and lower erythrocyte Mg levels in deficient rats. In conclusion, the reduced endurance capacity of Mg-deficient rats is not due to impaired 2,3-DPG production.
Growth of Leishmania donovani amastigotes in a continuous macrophage-like cell culture.

SYNOPSIS. The feasibility of using a macrophage-like murine tumor cell as a host for Leishmania donovani was investigated. This cell line, designated P388D1, rapidly phagocytized amastigotes and supported their intracellular replication. It can serve as a model “host” without the inherent limitations of primary macrophage cultures.
Modeling flow at the nozzle of a solid rocket motor

The mechanical behavior of a rocket motor internal flow field results in a system of nonlinear partial differential equations which can be solved numerically. The accuracy and the convergence of the solution of the system of equations depends largely on how precisely the sharp gradients can be resolved. An adaptive grid generation scheme is incorporated into the computer algorithm to enhance the capability of numerical modeling. With this scheme, the grid is refined as the solution evolves. This scheme significantly improves the methodology of solving flow problems in rocket nozzle by putting the refinement part of grid generation into the computer algorithm.