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1.
We have performed an extended replication of the Porter-Votta-Basili experiment comparing the Scenario method and the Checklist method for inspecting requirements specifications using identical instruments. The experiment has been conducted in our educational context represented by a more general definition of a defect compared to the original defect list. Our study involving 24 undergraduate students manipulated three independent variables: detection method, requirements specification, and the order of the inspections. The dependent variable measured is the defect detection rate. We found the requirements specification inspected and not the detection method to be the most probable explanation for the variance in defect detection rate. This suggests that it is important to gather knowledge of how a requirements specification can convey an understandable view of the product and to adapt inspection methods accordingly. Contrary to the original experiment, we can not significantly support the superiority of the Scenario method. This is in accordance with a replication conducted by Fusaro, Lanubile and Visaggio, and might be explained by the lack of individual defect detection skill of our less experienced subjects.  相似文献   
2.
Abstract The amount of volatile organic compounds (VOCs) in indoor air, usually called TVOC (total volatile organic compounds), has been measured using different definitions and techniques which yield different results. This report recommends a definition of TVOC referring to a specified range of VOCs and it proposes a method for the measurement of this TVOC entity. Within the specified range, the measured concentrations of identified VOCs (including 64 target compounds) are summed up, concentrations of non-identified compounds in toluene equivalents are added and, together with the identified VOCs, they give the TVOC value. The report reviews the TVOC concept with respect to its usefulness for exposure assessment and control and for the prediction of health or comfort effects. Although the report concludes that at present it is not possible to use TVOC as an effect predictor, it affirms the usefulness of TVOC for characterizing indoor pollution and for improving source control as required from the points of view of health, comfort, energy efficiency and sustainability.  相似文献   
3.
OBJECTIVE: To test a model for the study of inequalities in hospitalizations in the city of Ribeirao Preto (SP), understanding them to be due both to the social position of inpatients and also to health care policies in Brazil. MATERIAL AND METHOD: Using a hospital information system in existence for more than 25 years in the city of Ribeirao Preto-SP, 56.293 hospitalizations of municipal inhabitants occurring in some of the 12 general hospitals in 1993, were studied. Using the Brazilian occupancy classification for mortality, these inpatients were grouped on 6 occupational levels, as in the British classification: professional, intermediate, qualified non manual, qualified manual, partially qualified and unqualified. RESULTS AND CONCLUSIONS: Two-thirds of the inpatients had no place in the i.e. did not belong to the economically active population--and consisted of housewives, pensioners, children and students--and one third had some economic activity and thus belonged to the economically the active population. A close association was found between social strata and the classification of the hospital financing system into private, private group clinic and public health system patients. There were differences in hospital parameters as well as in morbidity patterns between these groups. The inequalities relating to average age, average age of hospital deaths, mean lengths of stay, hospital mortality, re-internment and frequency of diseases are discussed. This model allows the social position of the inpatient to be estimated using the hospital financing system, including also those patients with no economic activity, which covers the majority of the population. Social mechanisms created to compensate for inequalities in the welfare state do not cancel out the social differences.  相似文献   
4.
Total volatile organic compounds (TVOC) are determined in intake, room-supply and room air in 86 office rooms in 29 office buildings in northern Sweden. Measurements of formaldehyde were also made in room air. Building and room characteristics were identified and symptom reports collected from 1087 office workers. Concentrations of TVOC and formaldehyde in room air were low, with mean values of 71 µg/m3 and 31 µg/m3, respectively. The TVOC concentration was generally lower in room air than in supply air or intake air. The “loss” (difference in measured values) of TVOC from supply to room air was associated with raised concentrations of formaldehyde and raised prevalences of occupant symptoms. High TVOC concentrations in room air were associated with reduced prevalences of occupant symptoms.  相似文献   
5.
Nuclear microscopy based upon developments in high energy ion beam techniques is by now an accepted technique in many fields of research. The advancements into the biomedical field have, however, been slower than expected. A major factor explaining this tendency is the availability of nuclear microscopy. This paper reviews briefly the biomedical work using nuclear microscopy that has been carried out since the 4th International Conference on Nuclear Microprobe Technology and Applications held in Shanghai. Nuclear microscopy of isolated individual blood cells from patients adversely affected by metal exposure from dental amalgam has been performed both before and after removal of the metallic fillings. The elemental profile of blood cells was more or less normalised after treatment. Some of these results will be presented to illustrate a medical application. Results from bulk analysis by ICP-MS of erythrocytes and plasma before and after treatment will also be presented to illustrate the difference in information content between these two approaches as well as the need for complementary information in solving biomedical problems. As part of a larger study of acute porphyria, nuclear microscopy of blood cells was included among the 78 laboratory tests. The approach in this study was unbiased in the sense that no hypothesis was formulated as to which laboratory parameters would be the most explanatory for health or disease. Multivariate discriminant analysis was applied to the large amounts of data acquired. This approach led to the hypothesis that oxidative stress increased the synthesis of manganese-dependent superoxide dismutase in the mitochondria of polymorphonuclear leukocytes, explaining the increase of manganese in these cells. Antioxidant therapy was therefore applied to a couple of patients with porphyria, however, without clinical success.  相似文献   
6.
7.
In the adult brain, neurotrophin-3 (NT-3) is mainly localized in dentate granule cells, and its expression is decreased by various stimuli, e.g., seizure activity. We have examined the role of endogenous NT-3 for excitatory synaptic transmission at lateral perforant path-dentate granule cell synapses using hippocampal slices from NT-3 knock-out (+/-) and wild-type (+/+) mice. Paired-pulse facilitation (PPF) and also short-term synaptic plasticity induced by a brief, high-frequency train of afferent stimulation were reduced, but the expression of long-term potentiation was not affected in the NT-3+/- mice. Incubation of the slices with recombinant NT-3 reversed the deficit in PPF through a mechanism requiring de novo protein synthesis, implying that the impaired short-term plasticity does not result from a developmental alteration. No changes of overall presynaptic release probability, measured by the progressive block of NMDA receptor-mediated synaptic currents by MK-801, or desensitization of AMPA receptors were detected. Because NT-3 expression is reduced after focal seizures, impaired short-term facilitation may represent a protective response that limits the propagation of epileptiform activity from the entorhinal cortex to the hippocampus.  相似文献   
8.
5 different odorants, produced through combustion procedures of animal manure, were matched with hydrogen sulfide with regard to unpleasantness by 30 female 20-47 yr olds. Power functions described the unpleasantness matchings for 5 combustion toilets tested. The exponents of the equal sensation functions indicated a relative invariance of the various combustion procedures on the exponent. Different combustion procedures resulted in different levels of odor unpleasantness, but these differences were small from a practical point of view. Results demonstrate the practical applicability of psychophysical methods in environmental health research. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Considering the general impression of an increased number of patients with acute renal colic, the frequencies of roentgenologically verified ureteral and kidney calculi in a Swedish urban district have been studied for the periods 1953-55 and 1968-70. In a material of 986 outpatients (793 men and 193 women) we have proved an increase in incidence for upper urinary tract calculi in men from 2.2 to 3.3 0/00 (p less than 0.001) and in women from 0.5 to 0.8 0/00 (0.01 less than p less than 0.05). For the material as a whole, we have found a 50% increase (from 1.3 to 2.0 0/00; p less than 0.001) of acute urolithiasis between the periods studied. Some implications of the results in connection with primary hyperparathyroidism are discussed.  相似文献   
10.
We examined the therapeutic effect of cefluprenam (CFLP) on the polymicrobial urinary tract infection associated with infectious stones as compared to that of ceftazidime (CAZ), using the experimental polymicrobial urinary tract infection caused by Proteus mirabilis (P. mirabilis), Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus faecalis (E. faecalis). In order to form bladder stones in rats, a sterile zinc ring was implanted as a foreign body, followed by inoculating P. mirabilis E05106 transurethrelly. Thereafter, P. aeruginosa E030033 and E. faecalis 966 were inoculated according to the same way. CFLP or CAZ was administered intravenously twice a day for 5 days. The therapeutic effect was evaluated by the eradication of these bacteria from the urine, the kidney and stones, inhibition of growth of stones, and also a value of BUN. The urinary excretion rates of CFLP and CAZ was also determined (20 mg/kg). In result, CFLP significantly more effective in the eradication of P. mirabilitis, P. aeruginosa and E. faecalis from the urine, the kidney and stones than the control than the control (p < 0.05). Furthermore, CFLP significantly more effective in the eradication of P. aeruginosa from the urine and also E. facalis from the urine and stones (p < 0.05). Meanwhile, CAZ significantly more effective in the eradication of P. mirabilis from the urine, the kidney and stones and also P. aeraginosa from the kidney and stones than the control. However, CAZ did not show eradicative effect on E. faecalis. The urinary excretion rates of CFLP and CAZ at rats were 59.3% and 59.4%, respectively, within 8 hrs after administration, showing a similar excretion pattern. CFLP exhibited the prominent therapeutic effect on polymicrobial urinary tract infection associated with infectious stones caused by P. mirabilis, P. aeruginosa and E. faecalls. On the basis of these results, it has been strongly suggested that CFLP is highly beneficial in the management of intractable polymicrobial urinary tract infectious in clinic.  相似文献   
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