Near Source Acoustical Particle Velocity Measurements with Ambient Noise

An acoustical measurement very near a structure can be a cheap alternative to other contactless vibration measurement techniques such as laser vibrometry. However, measurements of the acoustical pressure suffer greatly from ambient noise, making these measurements unsuitable for many industrial applications. De Bree and Druyvesteyn suggested that a measurement of the acoustical particle velocity does not have this drawback and provided theory and qualitative measurement results [1]. We present quantitative measurement results of the relative noise contribution in pressure and particle velocity measurements. The ratio of these quantities receives special attention. The model used in previous research is a lumped model, in which some important aspects are neglected. We present results of a numerical model of the vibrating structure and the air. The numerical model and the measurements indicate the same trends but the lumped model does not describe the trends well. Nevertheless, this study also suggests that the sensitivity to background noise is generally considerably greater in pressure measurement than in a particle velocity measurement

Амбивалентно - эквилибраторное действие слабоминерализованных кремниевых вод на показатели водно-солевого обмена у жнвотных с моделью экспериментального предиабета

In the experiment on white rats with the model of pre-diabetes changes of water-salt exchange and their correction by internal course introduction of low-miniralization of silicic waters is grounded

Відкриття української книгарні “Смолоскип”

The present medication in Parkinson’s disease (PD) is unable to stop or slow down the progression of the disease. Therefore pharmacological intervention at crucial steps in the neuronal cell death processes would be a better strategy. Cannabinoids are potent neuroprotective compounds in models of oxidative stress and excitotoxicity and offer potential protection in models of PD. Therefore the present study determines the neuroprotective effects of 9- tetrahydrocannabinol ( 9-THC) in the marmoset 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model on behavior and pathology. Twelve marmoset monkeys were treated with a total cumulative dose of 6 mg/kg MPTP in 9 days. Seven of these animals received simultaneously a daily oral dose of 9-THC (4 mg/kg) and five animals received simultaneously vehicle for 27 days. The parkinsonian symptoms were observed daily and locomotor activity and hand-eye coordination were tested once a week during the experimental period. Postmortem, dopamine levels in the striatum were analyzed and tyrosine hydroxylase immunohistochemistry was applied to determine viable dopaminergic neurons in the substantia nigra. 9-THC has no protective effects on any parameter. These negative results might be related to the severity of the cell death induction by MPTP in relation to the low dose of 9-THC used in this Parkinson model

Схеми скорочення необхідного об'єму вимірювань у методі контролю стаціонарної підйомної установки

Предлагается последовательная процедура принятия решения относительно вектора характеристик контролируемой стационарной подъемной установки, которая является некоторым обобщением процедуры Вальда и позволяет получить выигрыш в среднем объеме испытаний, аналогичный обычному «вальдовскому» выигрышу для случая двух гипотез. Предлагаемая последовательная процедура позволяет учитывать дополнительную информацию и за счет этого получить добавочный выигрыш в объеме контроля стационарной подъемной установки.Offers a consistent decision-making procedure for the vector characteristics of the controlled stationary hoist, which is a generalization of Wald's procedure and provides a gain in the average volume of tests, similar to the usual "of Wald's" winning the case of two hypotheses. The proposed sequential procedure takes into account the additional information and thereby obtain additional gains in the amount of control a stationary hoist

Supine MRI for regional breast radiotherapy: Imaging axillary lymph nodes before and after sentinel-node biopsy

Regional radiotherapy (RT) is increasingly used in breast cancer treatment. Conventionally, computed tomography (CT) is performed for RT planning. Lymph node (LN) target levels are delineated according to anatomical boundaries. Magnetic resonance imaging (MRI) could enable individual LN delineation. The purpose was to evaluate the applicability of MRI for LN detection in supine treatment position, before and after sentinel-node biopsy (SNB). Twenty-three female breast cancer patients (cTis-3N0M0) underwent 1.5 T MRI, before and after SNB, in addition to CT. Endurance for MRI was monitored. Axillary levels were delineated. LNs were identified and delineated on MRI from before and after SNB, and on CT, and compared by Wilcoxon signed-rank tests. LN locations and LN-based volumes were related to axillary delineations and associated volumes. Although postoperative effects were visible, LN numbers on postoperative MRI (median 26 LNs) were highly reproducible compared to preoperative MRI when adding excised sentinel nodes, and higher than on CT (median 11, p < 0.001). LN-based volumes were considerably smaller than respective axillary levels. Supine MRI of LNs is feasible and reproducible before and after SNB. This may lead to more accurate RT target definition compared to CT, with potentially lower toxicity. With the MRI techniques described here, initiation of novel MRI-guided RT strategies aiming at individual LNs could be possible

Redefining radiotherapy for early-stage breast cancer with single dose ablative treatment: a study protocol

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