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51.
Investigations on the Efficacy of Preserving Agents in Anion Active Surfactants II The authors investigated the preserving action of p-chloro-m-cresol and of pHB-methyl/ethyl ester combination (1 + 1) in solutions of anion active surfactants. The preservatives were employed at two different concentrations. The concentration of the surfactants (lauryl sulfate and protein-fatty acid condensate as sodium, potassium and triethanolamine salts) was varied from 0.1 to 10.0 g/100 g. The pH of the solutions was 7. The deactivation of the preservatives investigated here by the anion active surfactant occurs only after a certain ratio of surfactant to preservative is reached. Under this ratio the preservatives are fully effective; above this, however, are the preservatives deactivated.  相似文献   
52.
Previous research indicates that individuals with antisocial personality disorder (ASPD) evidence low distress tolerance, which signifies impaired ability to persist in goal-directed behavior during an aversive situation, and is associated with a variety of poor interpersonal and drug use outcomes. Based on theory and research indicating that psychopathic traits are associated with hypo-reactivity in emotional responding, a unique hypothesis emerges where psychopathic traits should have the opposite effect of ASPD and be related to high levels of distress tolerance. In a sample of 107 substance-dependent patients in an inner-city substance use residential treatment facility, this hypothesis was supported. ASPD was related to lower distress tolerance, while psychopathic traits were related to higher distress tolerance, with each contributing unique variance. Findings are discussed in relation to different presentations of distress tolerance as a function of psychopathic traits among those with an ASPD diagnosis. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
53.
Balloon angioplasty as the treatment of first choice in the setting of an acute myocardial infarction (AMI) is gaining widespread acceptance because of favourable results from specialised centres concerning high patency rates and low mortality. This study reports the results of angioplasty for AMI at large community hospitals during 1992-1995. 4625 procedures were performed at 68 centres of the Arbeitsgemeinschaft Leitender Kardiologischer Krankenhaus?rzte (ALKK). The age of the patients was 60.8 +/- 11.3 years, with 75.1% men. The infarct related artery was the left anterior descendent in 43%, the right coronary artery in 37%, the circumflex artery in 16%, a bypass graft in 2.3% and the left main stem in 1.4% of patients. The success rate (residual stenosis < 50%) of the intervention was 86%. There was a wide range of procedures per centre, with a median of 40 AMI angioplasties per year and centre. The amount of angioplasties for AMI in relation to all angioplasties performed during this period rose from 5.2% in 1992 to 5.9% in 1995 (p = 0.01). Local complications at the puncture site occurred in 3.2%, with the need for a surgical intervention in 1.1% of patients. In 273 (5.9%) of the patients a second angioplasty was performed during the hospital stay. Aortocoronary bypass surgery was performed in 3% of the patients. Hospital mortality was 9.5% (438/4625 patients). The mortality rate remained constant during the years investigated (1992: 10.6%; 1993: 8.6%; 1994: 9.7%; 1995: 9.8%; p = ns). Higher mortality was observed in older patients, patients with multiple vessel disease, the left anterior descending artery or a bypass graft as infarct related artery as well as in patients with failed reperfusion (residual stenoses > 50%). Hospitals with a case load of more than 40 angioplasties for AMI per year showed a lower mortality as compared to the others. In clinical practice at large community hospitals results of angioplasty for AMI concerning mortality, complications and technical success rate are comparable to those of highly specialised centres. The absolute numbers of angioplasties for AMI increased constantly over the years.  相似文献   
54.
This paper presents a scalable method for parallelizing symbolic reachability analysis on a distributed-memory environment of workstations. We have developed an adaptive partitioning algorithm that significantly reduces space requirements. The memory balance is maintained by dynamically repartitioning the state space throughout the computation. A compact BDD representation allows coordination by shipping BDDs from one machine to another. This representation allows for different variable orders in the sending and receiving processes. The algorithm uses a distributed termination protocol, with none of the memory modules preserving a complete image of the set of reachable states. No external storage is used on the disk. Rather, we make use of the network, which is much faster.We implemented our method on a standard, loosely-connected environment of workstations, using a high-performance model checker. Initial performance evaluation of several large circuits shows that our method can handle models too large to fit in the memory of a single node. The partitioning algorithm achieves reduction in space, which is linear in the number of workstations employed. A corresponding decrease in space requirements is measured throughout the reachability analysis. Our results show that the relatively slow network does not become a bottleneck, and that computation time is kept reasonably small.  相似文献   
55.
Although several measures of obsessive-compulsive (OC) symptoms exist, most are limited in that they are not consistent with the most recent empirical findings on the nature and dimensional structure of obsessions and compulsions. In the present research, the authors developed and evaluated a measure called the Dimensional Obsessive-Compulsive Scale (DOCS) to address limitations of existing OC symptom measures. The DOCS is a 20-item measure that assesses the four dimensions of OC symptoms most reliably replicated in previous structural research. Factorial validity of the DOCS was supported by exploratory and confirmatory factor analyses of 3 samples, including individuals with OC disorder, those with other anxiety disorders, and nonclinical individuals. Scores on the DOCS displayed good performance on indices of reliability and validity, as well as sensitivity to treatment and diagnostic sensitivity, and hold promise as a measure of OC symptoms in clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
56.
Fiber scaffolds of bioactive polysialic acid have been prepared via electrospinning for peripheral nerve regeneration. The diameter, morphology and alignment of fibers in scaffolds were adjusted by variation of electrospinning parameters, which are decisive for the cell-scaffold interaction. Due to the high water solubility of polysialic acid (poly-α-2,8-N-acetylneuraminic acid) a photoactive derivative (poly-α-2,8-N-pentenoylneuraminic acid) was used to obtain stable fiber scaffolds in water by photochemical crosslinking. At the optimized fiber scaffolds good cell viability and directed cell proliferation along the fibers was achieved by cell tests with immortalized Schwann cells.  相似文献   
57.
Coronavirus disease (COVID-19) is a contagious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This case report presents a patient who had difficulty eradicating the corona virus due to being treated with Rituximab, which depletes B lymphocyte cells and therefore disables the production of neutralizing antibodies. The combined use of external anti-viral agents like convalescent plasma, IVIG and Remdesivir successfully helped the patient’s immune system to eradicate the virus without B-cell population recovery. In vitro studies showed that convalescent plasma is the main agent that helped in eradicating the virus.  相似文献   
58.
Reactive inkjet printing offers a direct way to create polymeric structures in situ on a substrate. Therefore, two component polyurethane formulations can be utilized to be used in multicomponent inkjet printing. In this contribution, the use of polyethylene glycol (M = 200 g mol−1), glycerol ethoxylate (M = 1,000 g mol−1), and water (blowing agent) in combination with aliphatic 1,6-hexamethylene diisocyanate or aromatic methylene diphenyl diisocyanate for reactive inkjet printing is evaluated. The inks are jettable on a Dimatix DMP-3000 inkjet printer using a 10 pL piezo driven drop-on-demand printhead showing stable droplet formation. Solid films on glass are formed using a drop-by-drop printing strategy. Layer-by-Layer strategy gives best results on polycarbonate substrates forming porous polyurethane structures. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46977.  相似文献   
59.
In this work we use Impedance Spectroscopy (IS) to study lead‐free ceramics of perovskite structure (Bi1/2Na1/2TiO3)0.925(BaTiO3)0.075 with Mn doping of 0, 0.2, 1.0, and 2.0 at.%. We compare our IS results with permittivity results, using dielectric to resistivity transformation equations which allow us to display results either as permittivity or as resistivity. We observe ionic conductivity dominating at lower temperatures, giving way to electronic conductivity at higher temperatures. The permittivity shows deviations from Curie‐Weiss behavior characteristic of relaxor ferroelectrics. The 0.2% Mn samples show the highest ionic resistivity, which will reduce heating for high voltage piezoelectric applications. They also have the highest Curie‐Weiss temperature and Burns temperature.  相似文献   
60.
Langmuir-Blodgett multilayers of hydrocarbon and fluorocarbon polymers with hydrophilic spacer, lipid-polyelectrolyte complexes and mesogenic polymers have been prepared. The thermal behaviour of the multilayers was studied by small angle X-ray scattering, IR and UV—visible spectroscopy. Good thermal stabilities were found for the various classes of polymers. In addition, for both complexed multilayers and mesogenic polymer films, reorientation processes were observed.  相似文献   
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