2,129 research outputs found
Simple derivation of the frequency dependent complex heat capacity
This paper gives a simple derivation of the well-known expression of the
frequency dependent complex heat capacity in modulated temperature experiments.
It aims at clarified again that the generalized calorimetric susceptibility is
only due to the non-equilibrium behaviour occurring in the vicinity of
thermodynamic equilibrium of slow internal degrees of freedom of a sample when
the temperature oscillates at a well determined frequency
Complications of percutaneous endoscopic gastrostomy in dogs and cats receiving corticosteroid treatment
BACKGROUND: Corticosteroid treatment is commonly required in veterinary patients for treatment of inflammatory, immuneâmediated, neurologic, and neoplastic diseases, which also may require assisted enteral nutrition via percutaneous endoscopic gastrostomy (PEG). OBJECTIVE: To evaluate complications associated with PEG use in dogs and cats receiving corticosteroid treatment. ANIMALS: Fortyâtwo animals were included in the study: 12 dogs and 2 cats in the steroid group and 26 dogs and 2 cats in the control group. METHODS: Medical records, between January 2006 and March 2015, were reviewed. Patients were included if the PEG tube was in use for at least 24 hours and if complete medical records were available. Patients were assigned to the control group if they were not treated with corticosteroids during PEG use or to the steroid group if they had received corticosteroids during PEG tube use. Complications were classified as minor, moderate, and major in severity. Maximum severity complication rate was compared between groups. RESULTS: The general prevalence of complications was found to be similar between groups (P = .306), but in the steroid group, 43% of the cases developed a major severity complication compared with 18% of the control group (P = .054). CONCLUSION AND CLINICAL IMPORTANCE: Owners of dogs and cats receiving corticosteroids, in which PEG is planned, should be counseled about possible complications beyond those associated with PEG tube usage alone
Quenched twisted mass QCD at small quark masses and in large volume
As a test of quenched lattice twisted mass QCD, we compute the
non-perturbatively O() improved pseudoscalar and vector meson masses and the
pseudoscalar decay constant down to at
in large volume. We check the absence of exceptional configurations
and -- by further data at -- the size of scaling violations. The
CPU time cost for reaching a given accuracy is close to that with ordinary
Wilson quarks at and grows smoothly as
decreases.Comment: 4 pages, 3 figures, to appear in Nucl. Phys. B (Proc. Suppl.
Liver and Pancreatic Resection in the Elderly
Background: Liver resection, or pancreaticoduodenectomy, has traditionally been thought to have a high morbidity and. mortality rate among the elderly. Recent improvements in surgical and anesthetic techniques, an increasing number of elderly patients, and an increasing need to justify use of limited health care resources prompted an assessment of recent surgical outcomes
Thermal oxidation of reactively sputtered amorphous W_(80)N_(20) films
The oxidation behavior of reactively sputtered amorphous tungsten nitride of composition W_(80)N_(20) was investigated in dry and wet oxidizing ambient in the temperature range of 450â°Câ575â°C. A single WO_3 oxide phase is observed. The growth of the oxide follows a parabolic time dependence which is attributed to a process controlled by the diffusivity of the oxidant in the oxide. The oxidation process is thermally activated with an activation energy of 2.5 ± 0.05 eV for dry ambient and 2.35 ± 0.05 eV for wet ambient. The preâexponential factor of the reaction constant for dry ambient is 1.1Ă10^(21) Ă
^2/min; that for wet ambient is only about 10 times less and is equal to 1.3Ă10^(20) Ă
^2/min
Factors in perioperative care that determine blood loss in liver surgery
AbstractObjectivesExcessive blood loss during liver surgery contributes to postoperative morbidity and mortality and the minimizing of blood loss improves outcomes. This study examines pre- and intraoperative factors contributing to blood loss and identifies areas for improvement.MethodsAll patients who underwent elective hepatic resection between June 2007 and June 2009 were identified. Detailed information on the pre- and perioperative clinical course was analysed. Univariate and multivariate analyses were used to identify factors associated with intraoperative blood loss.ResultsA total of 175 patients were studied, of whom 95 (54%) underwent resection of three or more segments. Median blood loss was 782ml. Greater blood loss occurred during major resections and prolonged surgery and was associated with an increase in postoperative complications (P= 0.026). Peak central venous pressure (CVP) of >10cm H2O was associated with increased blood loss (P= 0.01). Although no differences in case mix were identified, blood loss varied significantly among anaesthetists, as did intraoperative volumes of i.v. fluids and transfusion practices.ConclusionsThis study confirms a relationship between CVP and blood loss in hepatic resection. Intraoperative CVP values were higher than those described in other studies. There was variation in the intraoperative management of patients. Collaboration between surgical and anaesthesia teams is required to minimize blood loss and the standardization of intraoperative anaesthesia practice may improve outcomes following liver surgery
Greater than the Sum of its Parts: A Heterodinuclear Polymerization Catalyst
Homodinuclear
catalysts have good precedent for epoxide and carbon
dioxide/anhydride copolymerizations; in contrast, so far pure heterodinuclear
catalysts are unknown. The synthesis and properties of a heterodinuclear
ZnÂ(II)/MgÂ(II) complex coordinated by a symmetrical macrocyclic ligand
are reported. It shows high polymerization selectivity, control, and
significantly greater activity compared to either of the homodinuclear
analogues or any combinations of them. Indeed, compared to a 50:50
mixture of the homodinuclear complexes, it shows 5 times (CO<sub>2</sub>/epoxide) or 40 times (anhydride/epoxide) greater activity
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