bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boundary‐trapped, inhalant siphon and drain flows: Pipe entry revisited numerically
Authors: Jumars Peter A. 
Published: April 2013

Lay AbstractMany seafloor exchange processes are controlled or strongly influenced by pumping of water into projecting tubes or burrow openings flush with the seabed. Quantitative descriptions of flow inside tubes and burrow openings rely primarily on a model that assumes uniform flow at the pipe entrance and lacks any description of the upstream geometry or flow field. Quantifications of flows in front of the entrance generally assume omnidirectional, convergent flow into the pipe opening. Numerical models of a tube drawing water from a large volume and of a drain flush with the bottom drawing from the center of a large tank explicitly connect flow inside the pipe to the flow outside. They indicate—for slow, viscous, and small‐diameter (of the pipe) flows—that considerable flow adjustment occurs upstream of the pipe entrance and that uniform velocity at the entrance is a poor assumption. For these cases, flow entering the pipe comes from a relatively small, cylindrical region parallel with the pipe rather than being drawn from all possible directions. Uniform entrance flow never becomes a good approximation because much of the flow entering faster, less viscous, and larger‐diameter pipes enters with appreciable radial velocity that affects flow well into the pipe. These results alter estimates of pumping costs, which can represent appreciable fractions of animal energy budgets. They also determine the regions from which food and chemosensory information can be obtained. The results demonstrate the necessity for most applications to replace textbook models based on uniform entry flow.
Heat stress survival in the pre-adult stage of the life cycle in an intercontinental set of recombinant inbred lines ofDrosophila melanogaster
Authors: Sambucetti Pablo , Scannapieco Alejandra C. , Loeschcke Volker , Norry Fabian M. 
Published: April 2013

SummaryIn insects, pre-adult stages of the life cycle are exposed to variation in temperature that may differ from that in adults. However, the genetic basis for adaptation to environmental temperature could be similar between the pre-adult and the adult stages of the life cycle. Here, we tested quantitative trait loci (QTL) for heat-stress survival in larvae of D. melanogaster, with and without a mild-heat-stress pre-treatment. Two sets of recombinant inbred lines derived from lines artificially selected for high and low levels of knockdown resistance to high temperature in young flies were used as mapping population. There was no apparent increase in heat-shock survival between heat-pretreated and non-pretreated larvae. There was a positive correlation between the two experimental conditions of heat-shock survival (with and without a heat pre-treatment) except for males from one set of lines. Several QTL were identified involving all three major chromosomes. Many QTL for larval thermotolerance overlapped with thermotolerance-QTL identified in previous studies for adults. One new thermotolerance-QTL was found but these QTL explained only a small fraction of the phenotypic variance and were only significant in larvae that received no heat pre-treatment. Several candidate genes mapped within QTL ranges. We discuss an overall co-localization for thermotolerance-QTL between the adult fly in previous studies and the pre-adult stage of the life cycle in this study.
The effect of vasopressin 1b receptors (V1bRs) blockade on the HPA axis activity in rats exposed to acute heat stress
Authors: Jasnic Nebojsa I. , Djordjevic Jelena , Vujovic Predrag , Lakic Iva , Djurasevic Sinisa , Cvijic Gordana 
Published: April 2013

SummaryThermal stressors such as low and high ambient temperature elicit an abundance of neuroendocrine responses including activation of the hypothalamo-pituitary-adrenal (HPA) axis, and arginine-vasopressin (AVP) release. The exposure to heat is particularly interesting model for AVP action studying since this kind of stressor represents not only an unpleasant experience, but a threat to the osmotic homeostasis as well. As AVP has long been recognized as a hormone involved in the modulation of HPA axis activity, the aim of this study was to elucidate the AVP role in acutely heat exposed rats using Nelivaptan, a selective V1b receptor antagonist. Rats were exposed to high ambient temperature (38°C) for 60 minutes. The circulating hormones were determined by ELISA test or chemiluminescence method and Western blot was employed for determination of intrapituitary adrenocorticotropic hormone (ACTH) and V1bR level. The obtained results show that V1bR blockade negatively affected blood ACTH increase, caused by heat exposure. This treatment alone, or in combination with Nelivaptan decreased intrapituitary V1bR amount, while circulating AVP concentration was increased under the same conditions. Furthermore, strong correlation was observed between blood ACTH and corticosterone concentration. In conclusion, our results directly confirmed the positive role of AVP in the regulation of ACTH secretion from the pituitary in animals exposed to heat. Moreover, the results suggest that AVP from general circulation influence the pituitary V1bR.
Thermal physiology of the fingered limpet Lottia digitalis under emersion and immersion
Authors: Bjelde Brittany , Todgham Anne 
Published: April 2013

Summary
Marine animals living high in the rocky intertidal zone experience long durations of aerial-emersion, sometimes enduring rapid increases in temperature. To date, much of our understanding of the thermal physiology of intertidal organisms comes from studies in which organisms are exposed to increasing temperatures when immersed, with the added effect of aerial emersion rarely considered. In this study, we examined the physiological response of the finger limpet, Lottia digitalis, to increases in temperature under both immersed and emersed conditions. We investigated the thermal sensitivity and upper temperature tolerance of limpets through assessments of cardiac performance, metabolic rate, glycogen depletion and maintenance of protein integrity. Cardiac performance in response to ecologically relevant increases in temperature was similar in emersed and immersed limpets from 15 to 35°C and showed multiple break patterns in heart rate as temperature was increased. Overall, emersed limpets had a greater upper thermal limit on cardiac performance with the ability to maintain heart rate 3-5°C higher than immersed limpets. Metabolism in limpets also differed significantly between emersion and immersion, where a significant depression in aerobic metabolic rate was observed under immersion with increasing temperature. Greater levels of ubiquitin-conjugated proteins were found under emersed conditions compared to immersed limpets. Maintaining cardiac performance and aerobic metabolism to higher temperatures under emersed conditions is likely reflective of physiological adaptations to live in an aerially exposed environment. Measured field temperatures where fingered limpets were collected demonstrated that limpets have a narrow thermal safety margin for aerobic performance, and currently experience multiple days where summer temperatures might exceed their threshold limits.
Gas-Phase Acidities of α- and α,α-SO2CF3-Substituted Toluenes. Varying Resonance Demand in the Electron-Rich System
Authors: Zhang Min , Badal Md Mizanur Rahman , Koppel Ilmar A , Mishima Masaaki 
Published: April 2013

Abstract
The gas-phase acidities (GA) of aryl(trifluoromethylsulfonyl)methanes (ArCH2SO2CF3; 1) and arylbis(trifluoromethylsulfonyl)methanes (ArCH(SO2CF3)2; 2) were determined by measuring proton-transfer equilibria. Substituent effects for acidities of a series of ArCH(R1)R2 including 1 and 2 have been analyzed successfully in terms of the Yukawa–Tsuno equation. The resonance demand parameter r− value was found to decrease linearly with increasing acidity of the GA values of the unsubstituted parent carbon acids, and the change of the r− value was correlated with the acidifying effect of the phenyl group (R = Ph) in the RCH2(R1)R2. In addition, the geometric features and natural charges of the conjugate anions calculated at B3LYP/6-311+G(d,p) were found to be correlated linearly with the r− values. Such behavior of the resonance demand parameter in the electron-rich system, ArC−(R1)R2, is completely consistent with that observed for the electron-deficient system, ArC+(R1)R2, revealing that the resonance demand is contingent upon the structure of carbanions and carbocations. Furthermore, it was found that the ρ values also decreased with increasing acidity of the GA values of the unsubstituted parent carbon acids. This would be related to the distribution of the charge between the aromatic moiety and the C(R1)R2 moiety.
The Peripheral Knowledge Paradox: Interfirm Knowledge Partitioning and Integration in Services Contracting
Authors: Tiwana Amrit 
Published: April 2013

Specialized firms engaged in service offshoring contracts often face a tension between specializing in their own domain and maintaining knowledge in their partners' domains. When knowledge is “peripheral” to a firm's own specialty (e.g., an information technology (IT) service contractor's knowledge of a client's business domain or a client's technical knowledge of a contractor's domain), firms face a paradoxical dilemma of how much of such knowledge to invest in. This paper explores when it is important for clients and contractors to have in-house knowledge beyond their own, to be effective in IT service offshoring. We explore IT service engagements where it is more important for (a) the client to have deeper technical knowledge and (b) the contractor to have deeper business domain knowledge. We define the pattern of client–contractor knowledge overlaps as interfirm knowledge partitioning. The central thesis is that ex ante alignment between interfirm knowledge partitioning and service engagement newness enhances interfirm knowledge integration in offshoring engagements. To effectively organize service offshoring, solutions to interfirm knowledge integration problems in the presence of interfirm specialization are required; this is the underlying idea of this paper. The proposed model is tested using data on IT service offshoring engagements by 209 U.S. firms to foreign IT service firms. The findings offer novel theoretical insights into optimal interfirm knowledge partitioning in services contracting. Implications for service science theory and practice are also discussed.
Thermal Properties of Cu-Hf-Ti Metallic Glass Compositions
Authors: Figueroa I. A. 
Published: April 2013

ABSTRACTThe glass transition temperature Tg, crystallization temperature Tx, solidus temperature Tm, and liquidus temperature Tl, of a number of ternary Cu-Hf-Ti glassy alloys in the composition range of 51< Cu <67, 5 < Hf < 40 and 5 < Ti <40 (at.%) are reported and discussed. It is found that increasing the Ti:Hf ratio results in a rapid decreasing of Tg and Tx. This behavior is related to the fact that the melting point and cohesive energy for Ti are substantially lower than for Hf. The solidus temperature Tm, remains relatively constant on a wide range of compositions. The liquidus temperatures data suggest a ternary eutectic within the compositional field encompassed by the Cu55Hf20Ti25, Cu59Hf21Ti20, Cu60Hf20Ti20 and Cu55Hf21Ti24 alloys, with a liquidus temperature, Tl, of ∼1170 K; this is supported by the DTA traces, which show a single melting peak. Based on the DTA analysis, the experimentally calculated liquidus projection for the ternary Cu-Hf-Ti alloy system is also reported.
Geographic Variation in Black–White Differences in End-of-Life Care for Patients with ESRD
Authors: Thomas Bernadette A. , Rodriguez Rudolph A. , Boyko Edward J. , Robinson-Cohen Cassianne , Fitzpatrick Annette L. , O’Hare Ann M. 
Published: April 2013

Summary

Background and objectives
Patterns of end-of-life care among patients with ESRD differ by race. Whether the magnitude of racial differences in end-of-life care varies across regions is not known.

Design, setting, participants, & measurements
This observational cohort study used data from the US Renal Data System and regional health care spending patterns from the Dartmouth Atlas of Healthcare. The cohort included 101,331 black and white patients 18 years and older who initiated chronic dialysis or received a kidney transplant between June 1, 2005, and September 31, 2008, and died before October 1, 2009. Black–white differences in the odds of in-hospital death, dialysis discontinuation, and hospice referral by quintile of end-of-life expenditure index (EOL-EI) were examined.

Results
In adjusted analyses, the odds ratios for dialysis discontinuation for black versus white patients ranged from 0.47 (95% confidence interval=0.43 to 0.51) in the highest quintile of EOL-EI to 0.63 (95% confidence interval=0.54 to 0.74) in the lowest quintile (P for interaction<0.001). Hospice referral ranged from 0.55 (95% confidence interval=0.50 to 0.60) in the highest quintile of EOL-EI to 0.82 (95% confidence interval=0.69 to 0.96) in the lowest quintile (P for interaction<0.001). The association of race with in-hospital death also differed in magnitude across quintiles of EOL-EI, ranging from 1.21 (95% confidence interval=1.08 to 1.35) in the highest quintile of EOL-EI to 1.47 (95% confidence interval=1.27 to 1.71) in the second quintile (P for interaction<0.001).

Conclusions
There are pronounced black–white differences in patterns of hospice referral and dialysis discontinuation among patients with ESRD that vary substantially across regions of the United States.
Relationship-Specificity, Contract Enforceability, and Income Smoothing
Authors: Dou Yiwei , Hope Ole-Kristian , Thomas Wayne B. 
Published: April 2013

ABSTRACT:
Contracting parties, such as the firm and its supplier, have cost-reducing incentives to make investments that support the unique transactions between them. However, to the extent that one party may renege on its contractual obligations, the other party incurring the cost of the relationship-specific investment bears additional risk and is less willing to invest such that sub-optimal investment occurs. In countries where enforceability of explicit contracts is particularly weak, parties have incentives to signal their willingness to fulfill implicit claims and maintain long-term relationships. We predict that firms engage in income smoothing to send such a signal to their suppliers. Consistent with these expectations, we find that firms that both reside in countries with weak contract enforceability and operate in industries with a greater need for relationship-specific investments tend to smooth reported income more. We further decompose income smoothing into “informational” and “garbled” components and find that results are driven by the informational component of income smoothing. Our results support the important role that accruals play in providing information in the presence of incomplete contracts.
JEL Classifications: F14, K12, L14, M41, M43
Mechanisms of Glucose Lowering of Dipeptidyl Peptidase-4 Inhibitor Sitagliptin When Used Alone or With Metformin in Type 2 Diabetes
Authors: Solis-Herrera Carolina , Triplitt Curtis , Garduno-Garcia Jose de Jesús , Adams John , DeFronzo Ralph A. , Cersosimo Eugenio 
Published: April 2013

OBJECTIVE
To assess glucose-lowering mechanisms of sitagliptin (S), metformin (M), and the two combined (M+S).

RESEARCH DESIGN AND METHODS
We randomized 16 patients with type 2 diabetes mellitus (T2DM) to four 6-week treatments with placebo (P), M, S, and M+S. After each period, subjects received a 6-h meal tolerance test (MTT) with [14C]glucose to calculate glucose kinetics. Fasting plasma glucose (FPG), fasting plasma insulin, C-peptide (insulin secretory rate [ISR]), fasting plasma glucagon, and bioactive glucagon-like peptide (GLP-1) and gastrointestinal insulinotropic peptide (GIP) were measured.

RESULTS
FPG decreased from P, 160 ± 4 to M, 150 ± 4; S, 154 ± 4; and M+S, 125 ± 3 mg/dL. Mean post-MTT plasma glucose decreased from P, 207 ± 5 to M, 191 ± 4; S, 195 ± 4; and M+S, 161 ± 3 mg/dL (P &lt; 0.01). The increase in mean post-MTT plasma insulin and in ISR was similar in P, M, and S and slightly greater in M+S. Fasting plasma glucagon was equal (∼65–75 pg/mL) with all treatments, but there was a significant drop during the initial 120 min with S 24% and M+S 34% (both P &lt; 0.05) vs. P 17% and M 16%. Fasting and mean post-MTT plasma bioactive GLP-1 were higher (P &lt; 0.01) after S and M+S vs. M and P. Basal endogenous glucose production (EGP) fell from P 2.0 ± 0.1 to S 1.8 ± 0.1 mg/kg ⋅ min, M 1.8 ± 0.2 mg/kg ⋅ min (both P &lt; 0.05 vs. P), and M+S 1.5 ± 0.1 mg/kg ⋅ min (P &lt; 0.01 vs. P). Although the EGP slope of decline was faster in M and M+S vs. S, all had comparable greater post-MTT EGP inhibition vs. P (P &lt; 0.05).

CONCLUSIONS
M+S combined produce additive effects to 1) reduce FPG and postmeal plasma glucose, 2) augment GLP-1 secretion and β-cell function, 3) decrease plasma glucagon, and 4) inhibit fasting and postmeal EGP compared with M or S monotherapy.
Clinical, laboratory, and radiographic predictors of the occurrence of seizures following aneurysmal subarachnoid hemorrhage
Authors: Ibrahim George M. , Fallah Aria , Macdonald R. Loch 
Published: April 2013

Object
At present, the administration of prophylactic antiepileptic medication following aneurysmal subarachnoid hemorrhage (SAH) is controversial, and the practice is heterogeneous. Here, the authors sought to inform clinical decision making by identifying factors associated with the occurrence of seizures following aneurysm rupture.

Methods
Exploratory analysis was performed on 413 patients enrolled in CONSCIOUS-1 (Clazosentan to Overcome Neurological Ischemia and Infarction Occurring after Subarachnoid Hemorrhage), a prospective randomized trial of clazosentan for the prevention of angiographic vasospasm. The association among clinical, laboratory, and radiographic covariates and the occurrence of seizures following SAH were determined. Covariates with a significance level of p < 0.20 on univariate analysis were entered into a multivariate logistic regression model. Receiver operating characteristic (ROC) curve analysis was used to define optimal predictive thresholds.

Results
Of the 413 patients enrolled in the study, 57 (13.8%) had at least 1 seizure following SAH. On univariate analysis, a World Federation of Neurosurgical Societies grade of IV–V, a greater subarachnoid clot burden, and the presence of midline shift and subdural hematomas were associated with seizure activity. On multivariate analysis, only a subarachnoid clot burden (OR 2.76, 95% CI 1.39–5.49) and subdural hematoma (OR 5.67, 95% CI 1.56–20.57) were associated with seizures following SAH. Using ROC curve analysis, the optimal predictive cutoff for subarachnoid clot burden was determined to be 21 (of a possible 30) on the Hijdra scale (area under the curve 0.63).

Conclusions
A greater subarachnoid clot burden and subdural hematoma are associated with the occurrence of seizures after aneurysm rupture. These findings may help to identify patients at greatest risk for seizures and guide informed decisions regarding the prescription of prophylactic anticonvulsive therapy. Clinical trial registration no.: NCT00111085 (ClinicalTrials.gov).
La politique fiscalo-comptable des entreprises françaises : une étude exploratoire
Authors: Rossignol Jean-Luc 
Published: April 2013

La variable fiscale est susceptible d’influencer la détermination des choix comptables ; elle concourt à l’établissement d’une politique fiscalo-comptable de la firme. D’après les résultats de notre étude qui n’est qu’exploratoire, l’existence de cette politique se justifie par une organisation des fonctions comptable et fiscale particulièrement proche ainsi que par une perception essentiellement fiscale de l’utilité des comptes individuels.
Le rôle des contrôleurs de gestion dans l'apprentissage organisationnel : une analyse de la phase de suivi des réalisations
Authors: Bollecker Marc 
Published: April 2013

Cet article analyse la manière dont le contrôle de gestion, et plus précisément la phase de suivi des réalisations, peut contribuer à l’apprentissage organisationnel. Après avoir décrit les limites de l’approche « traditionnelle » ou « informationnelle » de l’apprentissage en contrôle de gestion, cette contribution se fonde sur le modèle de conversion des connaissances de I. Nonaka et H. Takeuchi, afin de mieux cerner le rôle des individus dans l’acquisition des savoirs au niveau de la phase de suivi des réalisations. Ce modèle, qui met notamment en valeur l’importance des réunions de suivi et du rôle des contrôleurs de gestion, sert de fondement à une étude empirique menée auprès de 81 entreprises industrielles françaises. L’étude montre que les contrôleurs de gestion contribuent à l’apprentissage organisationnel, en facilitant le déroulement des réunions de suivi par des activités de traduction.
A new method for determination of hyaluronidase activity in biological samples using capillary zone electrophoresis
Authors: Matysiak Jan , Dereziński Paweł , Urbaniak Bartosz , Klupczyńska Agnieszka , Zalewska Anna , Kokot Zenon J. 
Published: April 2013

ABSTRACTThe aim of the study was to develop a new capillary zone electrophoresis (CZE) method for determination of enzymatic activity of hyaluronidase. The method permits monitoring of the process of hyaluronic acid digestion by hyaluronidase. Studies were performed using CZE instrument equipped with capillary of 64.5 cm total length, 56 cm effective length and internal diameter 75 µm. Separation was performed in the phosphate buffer (pH 8.10) in the electric field of 20 kV, λ = 220 nm. The procedure was based on mixing a known quantity of hyaluronic acid and an aliquot of hyaluronidase solution, followed by obtaining CZE profiles after a known period of incubation (0.5 h). The activity of hyaluronidase was calculated using multiple regression analysis in which sizes of the peaks of the main degradation products were used. The newly developed method was fully validated and it is appropriate to evaluate the activity of hyaluronidase originating from different sources with high precision and accuracy. t‐Tests showed that there were no significant differences between results obtained using turbidimetric, viscosimetric and the new CZE method. The developed method is characterized by a short duration of analysis, low volume of analyzed sample, small amount of buffers used and low cost of analysis. Copyright © 2013 John Wiley & Sons, Ltd.