845 resultados para variable intensity


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Compartmental and physiologically based toxicokinetic modeling coupled with Monte Carlo simulation were used to quantify the impact of biological variability (physiological, biochemical, and anatomic parameters) on the values of a series of bio-indicators of metal and organic industrial chemical exposures. A variability extent index and the main parameters affecting biological indicators were identified. Results show a large diversity in interindividual variability for the different categories of biological indicators examined. Measurement of the unchanged substance in blood, alveolar air, or urine is much less variable than the measurement of metabolites, both in blood and urine. In most cases, the alveolar flow and cardiac output were identified as the prime parameters determining biological variability, thus suggesting the importance of workload intensity on absorbed dose for inhaled chemicals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Capacity is affected by construction type and its intensity on adjacent open traffic lanes. The effect on capacity is a function of vehicles moving in and out of the closed lanes of the work zone, and the presence of heavy construction vehicles. Construction activity and its intensity, however, are not commonly considered in estimating capacity of a highway lane. The main purpose of this project was to attempt to quantify the effects of construction type and intensity (e.g. maintenance, rehabilitation, reconstruction, and milling) on work zone capacity. The objective of this project is to quantify the effects of construction type and its intensity on work zone capacity and to develop guidelines for MoDOT to estimate the specific operation type and intensity that will improve the traffic flow by reducing the traffic flow and queue length commonly associated with work zones. Despite the effort put into field data collection, the data collected did not show a full speed-flow chart therefore extracting a reliable capacity value was difficult. A statistical comparison between the capacity values found in this study using either methodologies indicates that there is an effect of construction activity on the values work zone capacity. It was found that the heavy construction activity reduces the capacity. It is very beneficial to conduct similar studies on the capacity of work zone with different lane closure barriers, which is also directly related to the type of work zone being short-term or long-term work zones. Also, the effect of different geometric and environmental characteristics of the roadway should be considered in future studies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In humans, NK receptors are expressed by natural killer cells and some T cells, the latter of which are preferentially alphabetaTCR+ CD8+ cytolytic T lymphocytes (CTL). In this study we analyzed the expression of nine NK receptors (p58.1, p58.2, p70, p140, ILT2, NKRP1A, ZIN176, CD94 and CD94/NKG2A) in PBL from both healthy donors and melanoma patients. The percentages of NK receptor-positive T cells (NKT cells) varied strongly, and this variation was more important between individual patients than between individual healthy donors. In all the individuals, the NKT cells were preferentially CD28-, and a significant correlation was found between the percentage of CD28- T cells and the percentage of NK receptor+ T cells. Based on these data and the known activated phenotype of CD28- T cells, we propose that the CD28- CD8+ T cell pool represents or contains the currently active CTL population, and that the frequent expression of NK receptors reflects regulatory mechanisms modulating the extent of CTL effector function. Preliminary results indicate that some tumor antigen-specific T cells may indeed be CD28- and express NK receptors in vivo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

L’objecte del present treball és la realització d’una aplicació que permeti portar a terme el control estadístic multivariable en línia d’una planta SBR.Aquesta eina ha de permetre realitzar un anàlisi estadístic multivariable complet del lot en procés, de l’últim lot finalitzat i de la resta de lots processats a la planta.L’aplicació s’ha de realitzar en l’entorn LabVIEW. L’elecció d’aquest programa vecondicionada per l’actualització del mòdul de monitorització de la planta que s’estàdesenvolupant en aquest mateix entorn

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Quantificar les variables temporal, les accions tècniques i els desplaçaments dels jugador al llarg de la competició proporciona una informació excel·lent per deduir les càrregues físiques i fisiològiques a les que estan sotmesos. Per aquest estudi es van visualitzar 4 partits de la Copa del Rei 2012. Es va enregistrà sistemàticament les dades en fulls de registre. Les principals dades analitzades van ser: temps total, temps real, temps de pausa, temps d’acció i relació entre el temps d’acció i el temps de pausa (densitat de treball). També es va analitzar: les incidències reglamentaries, les accions tècniques del jugador i els desplaçaments del jugador. El 45% de les accions es van produir entre 0 i 30s, i el promig d’interval de participació va ser 19:29s ±2:09. Més del 50% de les pauses es van produir entre 11s i 30s, i el promig d’interval de pausa va ser de 24:57s. Aquest va determinar que la densitat de treball era 1:1.3. Aproximadament el 70% de les incidències reglamentàries van ser faltes d’equip I tècniques. Van haver-hi 56 conduccions, 10 driblins, 12 remats, (3 xuts, 2 punxades/escopides, 5 remats de primeres i 2 arrossegades) i 80 passades. Finalment, en un partit el 42,23% dels desplaçaments van ser a baixa intensitat, el 27,02% van ser a intensitat mitjana i el 30,75% van ser a alta intensitat. A més a més, el 81,90% dels desplaçaments a alta intensitat van durar de 0s a 5s, el 54,56% a intensitat mitjana van durar de 6 a 10 s. I el 49,32% a intensitat baixa també van durar 6s a 10s. L’hoquei sobre patins és un esport en el que hi predominen els esforços intermitents a gran intensitat i de curta durada amb una important sol·licitació de la via anaeròbica alàctica. Analitzar la dimensió temporal, les accions tècniques i els desplaçaments dels jugador durant la competició permet estimar les exigències físiques i requeriments energètics, i aquest faciliten l’elaboració d’entrenaments més específics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: In children with cystic fibrosis (CF), low immunoglobulin (IgG) levels have been reported to be associated with significantly less severe lung disease. However, decreased IgG can be a sign for common variable immunodeficiency (CVID) and affect clinical outcome. The aim of this study was to analyze clinical and serological data of patients having low IgG levels in routine blood tests at annual assessment, particularly their antibody response to polysaccharide antigens. Method: Retrospective chart review of demographic data of CF patients followed at the pediatric CF clinic throughout 2009. Clinical parameters (genotype, pancreas sufficiency, FEV1), presence of Pseudomonas aeruginosa (PA) and number of exacerbations per year were correlated with immunoglobulin and vaccination antibodies levels (antibodies to pneumococcal serotypes 14, 19, 23, 1, 5 and 7F measured by enzyme-linked immune-sorbent assay). Results: 4 out of 60 patients (6.7%) had lower IgG-levels for age. Ages ranged from 1 year 8 months to 11 years, 2 boys, 2 girls. Three patients were delF508 homozygotes, one heterozygote composite delF508/G542X. All were pancreatic insufficient. FEV1 ranged from 74 to 108%. One patient never had colonization by PA, 2 had intermittent PA colonization and one was chronically infected. After conjugated vaccination all patients had protective antibodies against serotypes 14, 19, 23F. For serotypes not included in the vaccine, only one patient had protective titers for 1 out of 3 serotypes. None of the patients had received unconjugated pneumococcal vaccine. There was no significant clinical difference in FEV1, PA colonization or number of exacerbations according to IgG and vaccination antibody levels. Conclusion: Cystic Fibrosis patients with low immunoglobulin levels have normal antibody response to protein antigens. However, despite recurrent infections, there seems to be delayed or deficient antibody response to polysaccharide antigens. Prospective studies are needed to evaluate the development of polysaccharide antibody responses in CF-patients to monitor for CVID. With early detection of CF by newborn screening program, long term follow up could be started early in childhood.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The comparison of radiotherapy techniques regarding secondary cancer risk has yielded contradictory results possibly stemming from the many different approaches used to estimate risk. The purpose of this study was to make a comprehensive evaluation of different available risk models applied to detailed whole-body dose distributions computed by Monte Carlo for various breast radiotherapy techniques including conventional open tangents, 3D conformal wedged tangents and hybrid intensity modulated radiation therapy (IMRT). First, organ-specific linear risk models developed by the International Commission on Radiological Protection (ICRP) and the Biological Effects of Ionizing Radiation (BEIR) VII committee were applied to mean doses for remote organs only and all solid organs. Then, different general non-linear risk models were applied to the whole body dose distribution. Finally, organ-specific non-linear risk models for the lung and breast were used to assess the secondary cancer risk for these two specific organs. A total of 32 different calculated absolute risks resulted in a broad range of values (between 0.1% and 48.5%) underlying the large uncertainties in absolute risk calculation. The ratio of risk between two techniques has often been proposed as a more robust assessment of risk than the absolute risk. We found that the ratio of risk between two techniques could also vary substantially considering the different approaches to risk estimation. Sometimes the ratio of risk between two techniques would range between values smaller and larger than one, which then translates into inconsistent results on the potential higher risk of one technique compared to another. We found however that the hybrid IMRT technique resulted in a systematic reduction of risk compared to the other techniques investigated even though the magnitude of this reduction varied substantially with the different approaches investigated. Based on the epidemiological data available, a reasonable approach to risk estimation would be to use organ-specific non-linear risk models applied to the dose distributions of organs within or near the treatment fields (lungs and contralateral breast in the case of breast radiotherapy) as the majority of radiation-induced secondary cancers are found in the beam-bordering regions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The functional interaction of BAFF and APRIL with TNF receptor superfamily members BAFFR, TACI and BCMA is crucial for development and maintenance of humoral immunity in mice and humans. Using a candidate gene approach, we identified homozygous and heterozygous mutations in TNFRSF13B, encoding TACI, in 13 individuals with common variable immunodeficiency. Homozygosity with respect to mutations causing the amino acid substitutions S144X and C104R abrogated APRIL binding and resulted in loss of TACI function, as evidenced by impaired proliferative response to IgM-APRIL costimulation and defective class switch recombination induced by IL-10 and APRIL or BAFF. Family members heterozygous with respect to the C104R mutation and individuals with sporadic common variable immunodeficiency who were heterozygous with respect to the amino acid substitutions A181E, S194X and R202H had humoral immunodeficiency. Although signs of autoimmunity and lymphoproliferation are evident, the human phenotype differs from that of the Tnfrsf13b-/- mouse model.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Ethical conflicts are arising as a result of the growing complexity of clinical care, coupled with technological advances. Most studies that have developed instruments for measuring ethical conflict base their measures on the variables"frequency" and"degree of conflict". In our view, however, these variables are insufficient for explaining the root of ethical conflicts. Consequently, the present study formulates a conceptual model that also includes the variable"exposure to conflict", as well as considering six"types of ethical conflict". An instrument was then designed to measure the ethical conflicts experienced by nurses who work with critical care patients. The paper describes the development process and validation of this instrument, the Ethical Conflict in Nursing Questionnaire Critical Care Version (ECNQ-CCV). Methods: The sample comprised 205 nursing professionals from the critical care units of two hospitals in Barcelona (Spain). The ECNQ-CCV presents 19 nursing scenarios with the potential to produce ethical conflict in the critical care setting. Exposure to ethical conflict was assessed by means of the Index of Exposure to Ethical Conflict (IEEC), a specific index developed to provide a reference value for each respondent by combining the intensity and frequency of occurrence of each scenario featured in the ECNQ-CCV. Following content validity, construct validity was assessed by means of Exploratory Factor Analysis (EFA), while Cronbach"s alpha was used to evaluate the instrument"s reliability. All analyses were performed using the statistical software PASW v19. Results: Cronbach"s alpha for the ECNQ-CCV as a whole was 0.882, which is higher than the values reported for certain other related instruments. The EFA suggested a unidimensional structure, with one component accounting for 33.41% of the explained variance. Conclusions: The ECNQ-CCV is shown to a valid and reliable instrument for use in critical care units. Its structure is such that the four variables on which our model of ethical conflict is based may be studied separately or in combination. The critical care nurses in this sample present moderate levels of exposure to ethical conflict. This study represents the first evaluation of the ECNQ-CCV.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Ethical conflicts are arising as a result of the growing complexity of clinical care, coupled with technological advances. Most studies that have developed instruments for measuring ethical conflict base their measures on the variables"frequency" and"degree of conflict". In our view, however, these variables are insufficient for explaining the root of ethical conflicts. Consequently, the present study formulates a conceptual model that also includes the variable"exposure to conflict", as well as considering six"types of ethical conflict". An instrument was then designed to measure the ethical conflicts experienced by nurses who work with critical care patients. The paper describes the development process and validation of this instrument, the Ethical Conflict in Nursing Questionnaire Critical Care Version (ECNQ-CCV). Methods: The sample comprised 205 nursing professionals from the critical care units of two hospitals in Barcelona (Spain). The ECNQ-CCV presents 19 nursing scenarios with the potential to produce ethical conflict in the critical care setting. Exposure to ethical conflict was assessed by means of the Index of Exposure to Ethical Conflict (IEEC), a specific index developed to provide a reference value for each respondent by combining the intensity and frequency of occurrence of each scenario featured in the ECNQ-CCV. Following content validity, construct validity was assessed by means of Exploratory Factor Analysis (EFA), while Cronbach"s alpha was used to evaluate the instrument"s reliability. All analyses were performed using the statistical software PASW v19. Results: Cronbach"s alpha for the ECNQ-CCV as a whole was 0.882, which is higher than the values reported for certain other related instruments. The EFA suggested a unidimensional structure, with one component accounting for 33.41% of the explained variance. Conclusions: The ECNQ-CCV is shown to a valid and reliable instrument for use in critical care units. Its structure is such that the four variables on which our model of ethical conflict is based may be studied separately or in combination. The critical care nurses in this sample present moderate levels of exposure to ethical conflict. This study represents the first evaluation of the ECNQ-CCV.