We aimed to evaluate dosimetric effects of ipsilateral shoulder position variations (ISPVs) in sitting-positioned boron neutron capture therapy (BNCT) for lower neck tumor. The ISPVs were simulated using deformed shou...
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We aimed to evaluate dosimetric effects of ipsilateral shoulder position variations (ISPVs) in sitting-positioned boron neutron capture therapy (BNCT) for lower neck tumor. The ISPVs were simulated using deformed shoulder images that can simulate arbitrary shape. The dose-volume parameters for the tumor in the rotated shoulder plans considerably varied compared with that for the mucosa. Even in a small number of cases, these differences were clearly observed among patients. The ISPVs in lower neck BNCT have great dosimetric effects.
Developmental toxicity studies for chemical and pharmaceutical safety are primarily performed in rats. Regulatory frameworks may require testing in a second, non-rodent species, for which the rabbit is usually chosen....
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Developmental toxicity studies for chemical and pharmaceutical safety are primarily performed in rats. Regulatory frameworks may require testing in a second, non-rodent species, for which the rabbit is usually chosen. This study shows that differences in NOAELs or LOAELs (N(L)OAELs) observed between rat and rabbit developmental toxicity studies performed according to OECD guidelines could just as well be caused by study replication errors, and not necessarily by differences in species sensitivity. This conclusion follows from an analysis of a database with rat and rabbit developmental toxicity studies for over 1000 industrial chemicals, pesticides, veterinary drugs and human pharmaceuticals, which included 143 compounds with multiple oral rat studies and 124 compounds with multiple oral rabbit studies. Our analysis confirms earlier findings that, on average over all compounds, rat and rabbit do not differ in sensitivity to developmental effects. There is substantial scatter in the correlation plots comparing rat and rabbit developmental N(L)OAELs, which is easily interpreted as species differences for individual compounds. However, for compounds tested twice in the same species, these N(L)OAELs may differ up to a factor of 25. Thus, potential interspecies differences in developmental N(L)OAEL will be overwhelmed by the reproducibility error, rendering the added value of a second species study questionable. As N(L)OAELs serve as point of departure (POD) for setting health-based guidance values in risk assessment, the large reproducibility error of N(L)OAELs should be taken into account by the introduction of an additional uncertainty factor. It is recommended to aim for reducing the reproducibility error by applying dose-response (BMD) analysis, optimize study designs and harmonize study protocols.
The paper deduced a calculation formula by the classic control theory on the reproducibility error of parts processing in the technology system, the flexible clamp system, with the clamping device on the gas power, an...
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ISBN:
(纸本)9780819485700
The paper deduced a calculation formula by the classic control theory on the reproducibility error of parts processing in the technology system, the flexible clamp system, with the clamping device on the gas power, and analyzed its influencing factor with examples, the reproducibility error law: The larger the diameter of the cylinder, the smaller the error;the slower the tool speed, (k values smaller), the smaller the error.
The paper deduced a calculation formula by the classic control theory on the reproducibility error of parts processing in the technology system,the flexible clamp system,with the clamping device on the gas power,and a...
详细信息
The paper deduced a calculation formula by the classic control theory on the reproducibility error of parts processing in the technology system,the flexible clamp system,with the clamping device on the gas power,and analyzed its influencing factor with examples,the reproducibility error law:The larger the diameter of the cylinder,the smaller the error;the slower the tool speed,(k values smaller),the smaller the error.
By using the classic control theory,the paper deduced a calculation formula on the reproducibility error of parts processing in the technology system,the flexible clamp system,with the clamping device on the gas power...
详细信息
By using the classic control theory,the paper deduced a calculation formula on the reproducibility error of parts processing in the technology system,the flexible clamp system,with the clamping device on the gas power,and analyzed its influencing factor with examples.
An improved design for pulse delay measurements using a Raman generating fibre pumped by a Nd:YAG laser has been realised. The reproducibility error in the measured delay times is only 2 ps RMS, because of strongly re...
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An improved design for pulse delay measurements using a Raman generating fibre pumped by a Nd:YAG laser has been realised. The reproducibility error in the measured delay times is only 2 ps RMS, because of strongly reduced jitter, compensation of long-term instability and prevention of irregularities in the shape of the pulses.
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