Correlation for Diffuse Radiation from Global Solar Radiation and Sunshine Data at Beijing, China

Solar radiation data are essential for the work of energy planners, engineers, and agricultural scientists. However, most solar radiation recording stations measure only global radiation in China. It is, therefore, necessary to elaborate correlations between the rarely available diffuse radiation and other climatic data. In the present study, 10-year data (1995–2004) of daily global diffuse solar radiation and sunshine duration obtained at Beijing meteorological station of China was analyzed to guide future projects. Nine models correlating the diffuse fraction (Kd) with both the clearness index (Kt) and percentage possible sunshine (S/S0) and each variable separately were tested. The accuracy of the correlations is performed in terms of the two widely used statistical indicators, mean bias error, and root mean square error. The results indicate that the correlations relating Kd with both Kt and S/S0 are more reliable than using each variable separately and Model 9 is preferred for its accuracy. The recorded data of Zhengzhou meteorological station are compared with the corresponding values predicted by Model 9 of Beijing. Model 9 provides predictions very close to the measured values of Zhengzhou. Therefore, it may be concluded that Model 9 can be used for estimating diffuse solar radiation for locations of semiwet region of the north of China where only global solar radiation and sunshine duration are available.     

Saturation effect of up-conversion luminescence from erbium-doped,silicatitania sol-gel powders

The intensity of the visible up-conversion luminescence could be limited by a saturation effect produced by increased pump power. Visible up-conversion luminescence was obtained in erbium doped,silica-titania sol gel powders under dynamical pumping at 1532 nm. The saturation effect was studied for erbium radiative transitions 2H9/2→4I15/2 (410 nm),2H11/2→4I15/2 (530 nm),4S3/2→4I15/2 (550 nm),2H9/2→4I13/2 (567 nm) and 4F9/2→4I15/2 (675 nm). The recorded up-conversion luminescence decreased when increasing ex...     

Activation of a CrmA-insensitive, p35-sensitive pathway in ionizing radiation-induced apoptosis

The response of eukaryotic cells to ionizing radiation (IR) includes induction of apoptosis. However, the signals that regulate this response are unknown. The present studies demonstrate that IR treatment of U-937 cells is associated with: (i) internucleosomal DNA fragmentation; (ii) cleavage of poly(ADP-ribose) polymerase; (iii) cleavage of protein kinase C delta; and (iv) induction of an Ac-DEVD-p-nitroanilide cleaving activity. Overexpression of the cowpox protein CrmA blocked tumor necrosis factor (TNF)-induced apoptosis but had no effect on IR-induced DNA fragmentation or cleavage of poly(ADP-ribose) polymerase and protein kinase C delta. By contrast, overexpression of the baculovirus p35 protein blocked both IR- and TNF-induced apoptosis. The results further demonstrate that the IR-induced proteolytic activity is directly inhibited by the addition of purified recombinant p35, but not by CrmA. We show that the CPP32 protease is sensitive to p35 and not CrmA. We also show that IR induces activation of CPP32 and that this event, like induction of apoptosis, is sensitive to overexpression of p35 and not CrmA. These findings indicate that IR-induced apoptosis involves activation of CPP32 and that this CrmA-insensitive apoptotic pathway is distinct from those induced by TNF and certain other stimuli.     

Radiation exposure in abdominal radiography with digital luminescence radiography and conventional screen-film system: an experimental animal study]

Progress in the care of the critically ill patient with life-threatening infection has been hampered by inconsistent, often confusing terminology. The clinical syndrome of sepsis-familiar to all yet definable by none-describes a highly heterogeneous group of disorders with different causes and differing prognoses. The imminent availability of mediator-directed therapy has created a sense of urgency to develop better methods for delineating discrete clinical syndromes and to modulate the host response, which may bring both benefit and harm, depending on the clinical circumstances. The term systemic inflammatory response syndrome (SIRS) was introduced several years ago to describe the familiar clinical syndrome of sepsis, independent of its cause. SIRS can result from trauma, pancreatitis, drug reactions, autoimmune disease, and a host of other disorders; when it arises in response to infection, sepsis is said to be present. SIRS describes a dynamic process that has adaptive survival value for the host. The maladaptive consequence of this process in the critically ill patient is the development of progressive but potentially reversible remote organ dysfunction-the multiple organ dysfunction syndrome. The development of cogent conceptual frameworks for classification of the septic response in critically ill patients is more than a question of linguistic pedantry. Optimal therapy presupposes identification of an homogeneous patient population with a characteristic disease process and a predictable response to an intervention. Although progress has been made in identifying such groups of critically ill patients, the disappointing results of clinical trials of agents that so clearly demonstrate efficacy in animal models indicates that considerable work remains.     

Respiratory and other responses in subjects immersed in cold water

Subjects have been immersed in water at 27 degrees C and 10 degrees C and while immersed their respiratory rates, minute volumes, and end-tidal PCO2 levels were measured. Measurements were made with the subjects at rest, exercising at approximately 0.8 liter oxygen-min-1, and very vigorously at 1.8-2.0 liters oxygen-min-1. Immersion in the cold water caused an increase in respiratory rate and a fall in end-tidal PCO2. At the moderate rate of exercise the hyperventilation persisted in relation to the oxygen demand and there was still a significant reduction in end-tidal PCO2. At the greatest rates of exercise, the end-tidal PCO2 did not differ from that obtained in similar rates of exercise in warm water. Preheating the subject in a sauna so as to increase skin temperature, with minimal change in body temperature, greatly attenuated the ventilatory and end-tidal PCO2 responses to cold water immersion. The significance of these findings is discussed.     

Radiation exposure during thoracic radiography at the intensive care unit. Dose accumulation and risk of radiation-induced cancer in long-term therapy

PURPOSE: Assessment of the additional morbidity risk due to repeated bedside chest radiography according to ICRP 60 during intensive care. MATERIAL AND METHODS: Ventral surface doses were recorded by thermoluminescence dosimetry in 2 man and 7 women, mean age 36 +/- 12 years, mean height 169 +/- 5 cm, mean weight 74 +/- 8 kg, receiving long-term ventilation therapy due to Adult Respiratory Distress Syndrome (ARDS). RESULTS: From 18 to 126 days duration of therapy 9 patients received a total of 348 bedside chest radiographs, mean 39 +/- 22 radiographs per patient. 217 chest radiographs yielded 217 surface doses and 217 gonadal doses. Patient's mean surface dose varies between at least 0.31 +/- 0.12 mGy and at most 0.56 +/- 0.09 mGy. The surface dose representing gonadal exposure is less than 0.03 mGy per exposure. The mean effective dose is about 0.15 mSv per exposure. The cumulative effective dose Heff ranges between 2.49 mSv and 14.09 mSv, thus estimating the additional individual cancer risk ranges between 0.01% and 0.07%. CONCLUSION: In comparison with the decreased prognosis of severely ill long-term ventilated patients the additional morbidity risk due to chest radiographs is a negligible quantity.