Thermal diffusivity of submicro- and nanocrystalline Zr–2.5% Nb and Zr–50% Nb alloys at high temperatures

Measurement data are given for the thermal diffusivity of Zr–2.5% Nb and Zr–50% Nb alloys both with the usual polycrystalline structure and with submicro- and nanocrystalline structures at high temperatures, which were determined in the automated mode using the dynamic technique of plane temperature waves.     

Influence of hypertonic saline solution infusion on defibrillation efficacy

BACKGROUND: Transplantation of lung allografts from the same donor into 2 recipients ("twinning") provides an opportunity to study recipient and donor factors that influence early allograft function. METHODS: Twenty-seven pairs of recipients were identified and evaluated using multivariate logistic regression analysis (p < 0.05). Four measures of early graft function were analyzed: alveolar-arterial gradient in the operating room, first alveolar-arterial gradient in the intensive care unit, alveolar-arterial gradient at 24 hours, and days of mechanical ventilation. RESULTS: Analysis of the pooled data without regard to pairing showed that alveolar-arterial gradient in the operating room was influenced by donor age, length of donor hospitalization, recipient mean pulmonary artery (PA) pressure at unclamping, and transplantation of a left lung. The alveolar-arterial gradient in the intensive care unit was correlated with donor age, donor cause of death, and mean PA pressure on arrival in that unit. Only mean PA pressure remained significant at 24 hours. Days of mechanical ventilation was determined by mean PA pressure on arrival in the intensive care unit, drop in mean PA pressure during operation, and diagnosis of the recipient. In the paired analysis, receiving a left lung, recipient diagnosis (pulmonary hypertension worse than others), and need of cardiopulmonary bypass were significantly associated with immediate graft dysfunction, although these influences did not persist beyond the immediate postoperative period. Donor arterial oxygen tension and time of ischemia were not significant predictors in any analysis. CONCLUSIONS: Immediate allograft function was associated with donor-related characteristics initially, but these lost importance over the ensuing 24 hours. Recipient PA pressure was an immediate and persisting influence. In the analysis of differences in function between the members of each pair, transplantation of the left lung, recipient diagnosis, and cardiopulmonary bypass were identified, but their influence did not persist beyond the first 6 hours.     

Benz(a)pyrene content in the salt samples obtained from the borehole waters of the Krasnodar deposit

Benz(a)pyrene content in the samples of salt obtained from water ground of the Krasnodar field was assayed by means of the spectral fluorescent method. The table salt "Extra" manufactured by the Slavyansk salt-works supplying the trade network (GOST 13830-68) served as control. 15 samples (60 reference standards) were examined. It was established that 3 of 5 tested samples obtained from purified concentrated brine of water ground of the Krasnodar field contained benz(a)pyrene in an amount of 0.0351 microgram/kg up to 0.16 microgram/kg. Benz(a)pyrene (0.104 microgram/kg) was detected in 1 of 4 tested samples of the salt "Extra". It is concluded that tested salt samples obtained from concentrated brine of water ground of the Krasnodar field contain an insignificant amount of benz(a)pyrene.     

Business process model abstraction: a definition, catalog, and survey

The discipline of business process management aims at capturing, understanding, and improving work in organizations by using process models as central artifacts. Since business-oriented tasks require different information from such models to be highlighted, a range of abstraction techniques has been developed over the past years to manipulate overly detailed models. At this point, a clear understanding of what distinguishes these techniques and how they address real world use cases has not yet been established. In this paper we systematically develop, classify, and consolidate the use cases for business process model abstraction and present a case study to illustrate the value of this technique. The catalog of use cases that we present is based on a thorough evaluation of the state of the art, as well as on our cooperation with end users in the health insurance sector. It has been subsequently validated by experts from the consultancy and tool vendor domains. Based on our findings, we evaluate how the existing business process model abstraction approaches support the discovered use cases and reveal which areas are not adequately covered, as such providing an agenda for further research in this area.     

From fine-grained to abstract process models: A semantic approach

Organizations actively managing their business processes face a rapid growth of the number of process models that they maintain. Business process model abstraction has proven to be an effective means to generate readable, high-level views on business process models by showing coarse-grained activities and leaving out irrelevant details. In this way, abstraction facilitates a more efficient management of process models, as a single model can provide for many relevant views. Yet, it is an open question how to perform abstraction in the same skillful way as experienced modelers combine activities into more abstract tasks. This paper presents an approach that uses semantic information of a process model to decide on which activities belong together, which extends beyond existing approaches that merely exploit model structural characteristics. The contribution of this paper is twofold: we propose a novel activity aggregation method and suggest how to discover the activity aggregation habits of human modelers. In an experimental validation, we use an industrial process model repository to compare the developed activity aggregation method with actual modeling decisions, and observe a strong correlation between the two. The presented work is expected to contribute to the development of modeling support for the effective process model abstraction.     

Analysis of patients referred to the gastroenterology service of a VA medical center

We recorded clinical information over a 12-month period on consecutive consultations to the gastroenterology service of the Durham VA Medical Center. Of 902 consultations, 789 were prospectively collected. Eighty-five percent of the patients were between 40 and 70 years old. Seventy-five percent of the referrals were from the internal medicine service. The most frequent reasons for consultation were abdominal pain (19%), GI bleeding (active, 16%; occult, 9%), abnormal results of liver tests (18%), and request for a procedure (11%). Diseases of the liver (32%) and "peptic diseases" (30%) were the most common diagnoses. One or more procedures were done in 71% of consultations. When these data are compared with those of a practicing gastroenterologist, using an identical instrument, it is apparent that trainees' experience with structurally identifiable gastroenterologic disease and with a variety of procedures was similar in scope. There were, however, differences in that the physicians at the VA saw substantially fewer patients with so-called "functional" illness. If these data are applicable to other VA Medical Centers, then the training of physicians in gastroenterology at a VA Medical Center should probably be broadened.     

Acute acid-base disorders. 2. Specific disturbances

Evaluation of the acid-base status of the body requires measurement of bicarbonate (total carbon dioxide) concentration, pH, and partial pressure of CO2 in arterial blood. Calculation of standard bicarbonate and base excess or deficit is not necessary. The normal concentration of free hydrogen ions (H+) is approximately 40 millimoles/liter, which is equivalent to a pH of 7.4. The normal load of fixed acids is 50 to 80 millimoles in 24 hours. A steady state is maintained by excretion of an equal amount of H+ by the kidneys, which at the same time regenerate bicarbonate to replenish buffer stores. Renal excretion of H+ is in the form of titratable acid and ammonium. Synthesis of ammonia can increase severalfold under the stimulus of acidosis. This is the chief mechanism of long-term compensation. Metabolic acidosis can be due to an excessive acid load (endogenous or exogenous), impaired renal excretion of H+, or bicarbonate loss. Determination of the "anion gap" (unmeasured anions) helps to establish the mechanism of acidosis. Acidosis with a normal anion gap is due to either bicarbonate loss or ingestion of certain chloride salts. A gap larger than normal indicates the presence in the body of acids other than acidfying chloride salts. Management of metabolic acidosis requires accurate diagnosis, clear understanding of the mechansim, and individualized treatment. Metabloic alkalosis is due to loss of H+ (usually from stomach or kidneys) or ingestion of alkali. Measurement of urinary chloride helps establish the mechanism of alkalosis. In saline-responsive alkalosis, the urinary chloride level is very low. This is usually due to gastric loss of H+, and the condition responds to administration of saline solution. When the urinary chloride level is only moderately low, the alkalosis is probably not due to gastric loss of H+. This form of alkalosis (saline-resistant) does not respond well to administration of saline solution and requires use of potassium in treatment. Apprpriate compensatory responses to acidosis or alkalosis are critical to survival. Compensation for metabloic acidosis consists of hyperventilation and enhanced renal excretion of H+, chiefly as ammonium. In metabolic alkalosis, compensation is mainly renal excretion of bicarbonate. Respiratory acidosis is due to alveolar hypoventilation. In chronic situations, a compensatory rise in serum bicarbonate concentration is expected. Management consists of treatment of the cause of hypoventilation. Respiratory alkalosis is due to hyperventilation. Treatment requires identification and correction of the cause of hyperventilation.     

A kinetic analysis of the changes in fluorescence on the interaction of 8-anilinonaphthalene-1-sulphonate with submitochondrial particles

Residual deficiency of brain performance in chronic alcoholics after a 5-year abstinency. Brain performance of a group of 43 chronic alcoholics abstinent since 5 years was tested. Some aspects of higher intellectual performance were found to be reduced as compared to a control population. The performance was also better than that of a group of chronic alcoholics abstinent for only one year. The residual deficiency of performance could be interpreted as a "functional psychosyndrome", resulting from chronic sensory deprivation on the base of the alcoholism.