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221.
Takada M Mihara E Sasaki M Nakamura T Honma T Kono K Fujitaka K 《Radiation protection dosimetry》2004,110(1-4):601-606
Biological data is necessary for estimation of protection from neutrons, but there is a lack of data on biological effects of neutrons for radiation protection. Radiological study on fast neutrons has been done at the National Institute of Radiological Sciences. An intense neutron source has been produced by 25 MeV deuterons on a thick beryllium target. The neutron energy spectrum, which is essential for neutron energy deposition calculation, was measured from thermal to maximum energy range by using an organic liquid scintillator and multi-sphere moderated 3He proportional counters. The spectrum of the gamma rays accompanying the neutron beam was measured simultaneously with the neutron spectrum using the organic liquid scintillator. The transmission by the shield of the spurious neutrons originating from the target was measured to be less than 1% by using the organic liquid scintillator placed behind the collimator. The measured neutron energy spectrum is useful in dose calculations for radiobiology studies. 相似文献
222.
This paper considers the use of cubic splines, instead of polynomials, to represent the static nonlinearities in block structured models. It introduces a system identification algorithm for the Hammerstein structure, a static nonlinearity followed by a linear filter, where cubic splines represent the static nonlinearity and the linear dynamics are modeled using a finite impulse response filter. The algorithm uses a separable least squares Levenberg-Marquardt optimization to identify Hammerstein cascades whose nonlinearities are modeled by either cubic splines or polynomials. These algorithms are compared in simulation, where the effects of variations in the input spectrum and distribution, and those of the measurement noise are examined. The two algorithms are used to fit Hammerstein models to stretch reflex electromyogram (EMG) data recorded from a spinal cord injured patient. The model with the cubic spline nonlinearity provides more accurate predictions of the reflex EMG than the polynomial based model, even in novel data. 相似文献
223.
224.
Stepakoff Shanee; Hubbard Jon; Katoh Maki; Falk Erika; Mikulu Jean-Baptiste; Nkhoma Potiphar; Omagwa Yuvenalis 《Canadian Metallurgical Quarterly》2006,61(8):921
From 1999 to 2005, the Minneapolis-based Center for Victims of Torture (CVT) served Liberian and Sierra Leonean survivors of torture and war living in the refugee camps of Guinea. A psychosocial program was developed with 3 main goals: (a) to provide mental health care, (b) to train local refugee counselors, and (c) to raise community awareness about war trauma and mental health. Utilizing paraprofessional counselors under the close, on-site supervision of expatriate clinicians, the treatment model blended elements of Western and indigenous healing. The core component consisted of relationship-based supportive group counseling. Clinical interventions were guided by a 3-stage model of trauma recovery (safety, mourning, reconnection), which was adapted to the realities of the refugee camp setting. Over 4,000 clients were provided with counseling, and an additional 15,000 were provided with other supportive services. Results from follow-up assessments indicated significant reductions in trauma symptoms and increases in measures of daily functioning and social support during and after participation in groups. The treatment model developed in Guinea served as the basis for CVT's ongoing work with survivors in Sierra Leone and Liberia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
225.
Masaru Sato Hiroaki Tanaka Koji Inaka Shinichi Shinozaki Ari Yamanaka Sachiko Takahashi Mari Yamanaka Erika Hirota Shigeru Sugiyama Mitsuyasu Kato Chie Saito Satoshi Sano Moritoshi Motohara Tai Nakamura Tomoyuki Kobayashi Susumu Yoshitomi Tetsuo Tanaka 《Microgravity science and technology》2006,18(3-4):184-189
Since 2003, Japan Aerospace Exploration Agency (JAXA, former NASDA) has been conducting a project on a semi-annual basis (JAXA-GCF) to obtain high-quality protein crystals in the microgravity environment using the Russian transportation system. For this project, protein samples were mostly provided by Japanese users for whom JAXA provided technical and clerical support for crystallization experiments in microgravity. For the project, JAXA has constructed a user-friendly support service for microgravity experiments and provided regular and frequent flight opportunities. To simplify and improve technological matters, JAXA devised a gel-tube method crystallization device, which is effective both in space and on ground, based on the counter-diffusion technique. JAXA also provided ground-based techniques for efficient preliminary optimization of crystallization conditions using a 1-dimensional simulation and for harvesting and cryoprotecting crystals before X-ray diffraction experiments. These improvements have significantly increased the success rate of obtaining useful results. In conclusion, JAXA has developed technologies for growing, in microgravity, high-quality protein crystals, which may diffract up to atomic resolution, for a better understanding of 3-dimensional protein structures through X-ray diffraction experiments. 相似文献
226.
227.
Emborg J Matjačić Z Bendtsen JD Spaich EG Cikajlo I Goljar N Andersen OK 《IEEE transactions on bio-medical engineering》2011,58(4):960-970
A novel closed-loop system for improving gait in hemiparetic patients by supporting the production of the swing phase using electrical stimulations evoking the nociceptive withdrawal reflex was designed. The system exploits the modular organization of the nociceptive withdrawal reflex and its stimulation site- and gait-phase modulation in order to evoke movements of the hip, knee, and ankle joints during the swing phase. A modified model-reference adaptive controller (MRAC) was designed to select the best stimulation parameters from a set of 12 combinations of four electrode locations on the sole of the foot and three different stimulation onset times between heel-off and toe-off. It was hypothesized that the MRAC system would result in a better walking pattern compared with an open-loop preprogrammed fixed pattern of stimulation (FPS) controller. Thirteen chronic or subacute hemiparetic subjects participated in a study to compare the performance of the two control schemes. Both control schemes resulted in a more functional gait compared to no stimulation (P < 0.05) with a weighted joint angle peak change of 4.0 ± 1.6 (mean ± Standard deviation) degrees and 3.1 ± 1.4 degrees for the MRAC and FPS schemes, respectively. This indicates that the MRAC scheme performed better than the FPS scheme (P < 0.001) in terms of reaching the control target. 相似文献
228.
Thomas Bechtold Rita Mussak Amalid Mahmud‐Ali Erika Ganglberger Susanne Geissler 《Journal of the science of food and agriculture》2006,86(2):233-242
The food and beverage industry releases considerable amounts of wastes which contain natural dyes. Such wastes could serve as a sources for the extraction of natural dyes for textile‐dyeing operations. The extraction of brilliant yellow and red colours from fruits and vegetables is of particular interest. Wastes, e.g. pressed berries, pressed grapes, distillation residues from strong liquor production, and wastes and peels from vegetable processing, have been extracted with boiling water and test dyeings on wool yarn were performed. Colour strength, shade and fastness properties of the dyeings have been tested. The extracts were applied as direct dyes and in the presence of iron(II) or alum mordants. The results prove the potential of such wastes as a source for natural dyestuff extraction. To obtain textile dyeings with acceptable fastness properties, however, rigorous selection of dyes and development of suited processes is required. A considerable number of red natural dyes need further research to optimise the low level of fastness to light. Copyright © 2005 Society of Chemical Industry 相似文献
229.
Hernández Erika Sandoval Llewellyn Smith Stefan G. Cros Anne 《Journal of Mechanical Science and Technology》2020,34(4):1459-1465
Journal of Mechanical Science and Technology - This work presents a theoretical and experimental study of a flexible plate immersed in a von Kármán vortex street. The wake is generated in... 相似文献
230.
Alessandro Agnarelli Andrea Lauer Betrn Athanasios Papakyriakou Viviana Vella Mark Samuels Panagiotis Papanastasopoulos Christina Giamas Erika J. Mancini Justin Stebbing John Spencer Chiara Cilibrasi Angeliki Ditsiou Georgios Giamas 《International journal of molecular sciences》2023,24(1)
Recently, the oncogenic role of lemur tyrosine kinase 3 (LMTK3) has been well established in different tumor types, highlighting it as a viable therapeutic target. In the present study, using in vitro and cell-based assays coupled with biophysical analyses, we identify a highly selective small molecule LMTK3 inhibitor, namely C36. Biochemical/biophysical and cellular studies revealed that C36 displays a high in vitro selectivity profile and provides notable therapeutic effect when tested in the National Cancer Institute (NCI)-60 cancer cell line panel. We also report the binding affinity between LMTK3 and C36 as demonstrated via microscale thermophoresis (MST). In addition, C36 exhibits a mixed-type inhibition against LMTK3, consistent with the inhibitor overlapping with both the adenosine 5′-triphosphate (ATP)- and substrate-binding sites. Treatment of different breast cancer cell lines with C36 led to decreased proliferation and increased apoptosis, further reinforcing the prospective value of LMTK3 inhibitors for cancer therapy. 相似文献