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131.
The target-based phasing of an optical phased array (OPA) fed by a broadband master oscillator laser source is investigated. The specific scenario examined here considers an OPA phasing through atmospheric turbulence on a rough curved object. An analytical expression for the detected or received intensity is derived. Gleaned from this expression are the conditions under which target-based phasing is possible. A detailed OPA wave optics simulation is performed to validate the theoretical findings. Key aspects of the simulation set-up as well as the results are thoroughly discussed. 相似文献
132.
IV Ole?chik 《Canadian Metallurgical Quarterly》1998,98(2):13-19
A clinical and follow-up study of 155 young adults with a symptomcomplex of "juvenile asthenic deficiency"--"endogener juveniler asthenischer Versagensyndrome" (J.Glatzel, G.Huber, 1968) was carried out. It was found that protracted states in the youth with prevalence of educational disadaptation, weakening of initiative, psychophysical fatiguability should be attributed to atypical depressions, characterized by predominance of ideatoric disturbances with obliterated thymic and motor components. Depending on the specificities of ideatoric disturbances, 3 basic typological varieties of such depressions were recognized, i.e. depressions with prevalence of inhibition, disautomatization or distortion of cognitive processes, which statistically correlated reliably with definite nosological forms (affective disorders, schizophrenia). Depending on the nosologic belonging the studied states differed also in frequency of comorbid disturbances (obsessive-phobic, depersonalization, overvalued ideas), which occurred significantly rarer in the cases of affective disorders, than in schizophrenia. On the whole, follow-up study revealed relatively favourable prognosis of youth endogenous depressions with a clinical picture of "juvenile asthenic deficiency": in cases of affective disorders the course of disease was more frequently in the form of a single cyclothymic attack, while in cases of schizophrenia it took the form of protracted atypical pubertal attack. 相似文献
133.
VIVIANE DAL-SOUTO FRESCURA RIELLE WOUTERS KUHN HAYWOOD DAIL LAUGHINGHOUSE IV JUÇARA TEREZINHA PARANHOS SOLANGE BOSIO TEDESCO 《Biocell》2013,37(2):23-28
Species of the genus Psychotria are used for multiple purposes in Brazilian folk medicine, either
as water infusions, baths or poultices. This study was aimed to evaluate the genotoxic and antiproliferative
effects of infusions of Psychotria brachypoda and P. birotula on the Allium cepa test. Exposure to distilled
water was used as a negative control, while exposure to glyphosate was used as a positive control. The interaction of extracts (as a post-treatment) with the effects of glyphosate was also studied. Results showed that
glyphosate and the extracts of both P. brachypoda and P. birotula reduced the mitotic index as compared with
the negative control (distilled water). Surprisingly, however, both extracts from P. brachypoda and P. birotula
caused a partial reversal of the antiproliferative effect of glyphosate when used as a post-treatment. Glyphosate also induced the highest number of cells with chromosomal alterations, which was followed by that of
P. birotula extracts. However, the extracts from P. brachypoda did not show any signifi cant genotoxic effect.
Post-treatment of glyphosate-treated samples with distilled water allowed a partial recovery of the genotoxic
effect of glyphosate, and some of the Psychotria extracts also did so. Notably, post-treatment of glyphosatetreated samples with P. brachypoda extracts induced a statistically signifi cant apoptotic effect. It is concluded
that P. brachypoda extracts show antiproliferative effects and are not genotoxic, while extracts of P. birotula
show a less potent antiproliferative effect and may induce chromosomal abnormalities. The finding of a partial
reversion of the effects of glyphosate by a post-treatment with extracts from both plants should be followed up. 相似文献
134.
The interactive effect of fungicide residues and yeast assimilable nitrogen on fermentation kinetics and hydrogen sulfide production during cider fermentation
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135.
136.
Jay Edneil C. Olivar Joanner Paulus Erik P. Alaba Jose Francisco M. Atienza Jerick Jeffrey S. Tan Maximo T. Umali IV Grecebio Jonathan D. Alejandro 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(5):741-748
The majority of the population in the Philippines relies on herbal products as their primary source for their healthcare needs. After the recognition of Vitex negundo L. (lagundi) as an important and effective alternative medicine for cough, sore throat, asthma and fever by the Philippine Department of Health (DOH), there was an increase in the production of lagundi-based herbal products in the form of teas, capsules and syrups. The efficiency of these products is greatly reliant on the use of authentic plant material, and to this day no standard protocol has been established to authenticate plant materials. DNA barcoding offers a quick and reliable species authentication tool, but its application to plant material has been less successful due to (1) lack of a standard DNA barcoding loci in plants and (2) poor DNA yield from powderised plant products. This study reports the successful application of DNA barcoding in the authentication of five V. negundo herbal products sold in the Philippines. Also, the first standard reference material (SRM) herbal library for the recognition of authentic V. negundo samples was established using 42 gene accessions of ITS, psbA-trnH and matK barcoding loci. Authentication of the herbal products utilised the SRM following the BLASTn and maximum-likelihood (ML) tree construction criterion. Barcode sequences were retrieved for ITS and psbA-trnH of all products tested and the results of the study revealed that only one out of five herbal products satisfied both BLASTn and ML criterion and was considered to contain authentic V. negundo. The results prompt the urgent need to utilise DNA barcoding in authenticating herbal products available in the Philippine market. Authentication of these products will secure consumer health by preventing the negative effects of adulteration, substitution and contamination. 相似文献
137.
138.
Kimberly P. Ellis Russell D. Meller Joseph H. Wilck IV Pratik J. Parikh Franky Marchand 《国际生产研究杂志》2013,51(23):7195-7217
Effective material flow in an assembly facility leads to reduced material handling costs and increased productivity. This research focuses on improving the flow of materials for an assembly facility that receives supplied parts through receiving docks and transfers the parts to material storage locations and then to part usage locations. The locations of the receiving docks, storage locations, and line locations are predetermined, but the assignment of parts to dock locations and storage locations and the material flow paths through the facility are decision variables. Furthermore, design decisions such as the dock strategy employed and the configuration of the storage areas lead to additional decision variables. The goal is to reduce overall material handling costs by effectively receiving, storing and transferring the material from loading docks to line locations. The contribution of this research is in applying multi-commodity network flow models that integrate many of the sub-problems that are assumed to be solved a priori in many existing models. This integrated approach was used to evaluate configuration changes for a collaborating facility. One of the scenarios analysed showed an improvement in the material handling costs of nearly 10% as compared to current practices. 相似文献
139.
A relation is derived between the mismatch strain, the film thickness, and the displacement of a linear elastic structure
under external loading during material deposition. If any two of these variables can be experimentally determined, then the
remaining variable can be determined. The method allows one to experimentally determine the mismatch strain by measuring the
film thickness and the displacement of a point on the structure that is not undergoing deposition. The intrinsic stresses
can be used to self-assemble microstructures during material deposition. Assembly of two components is considered: one component
is subjected to deposition and is modeled as an Euler-Bernoulli beam, and the other component is not subjected to deposition
and is modeled as a linear spring. For the purposes of this paper, the definition of assembly requires that the beam do work
on the spring. The analysis is experimentally verified by electroplating nickel onto an AFM cantilever beam in contact with
a second AFM beam (serving as the spring) that does not undergo deposition.
This paper was recommended for publication in revised form by Associate Editor Maenghyo Cho
Sang-Hyun Kim obtained his B. S. (1993) and M.S. (1995) degrees in Aerospace Engineering from Pusan Nation University and Ph.D. (2005)
in Aerospace Engineering from Texas A&M University. After getting Ph.D., he joined Micro Systems Lab. at Samsung Advanced
Institute of Technology (SAIT) and worked in the field of MEMS designs, especially microsensors, microactuator and inkjet
print head. He is currently working as a faculty member in Mechanical Systems Engineering at Hansung University. His research
interest lies in design, fabrication and test of MEMS/NEMS. He is also interested in the development of design platform of
multi-physics and multiscale phenomena. 相似文献
140.
Jimmie C. Oxley Joseph E. Brady IV Austin C. Brown 《Propellants, Explosives, Pyrotechnics》2012,37(1):24-39
Thermal behaviors, vapor pressures, densities, and drop weight impact results, as well as analytical protocols, are reported for three tetranitrate esters: erythritol tetranitrate (ETN), 1,4‐dinitrato‐2,3‐dinitro‐2,3bis(nitratomethylene) butane (DNTN), and pentaerythritol tetranitrate (PETN). ETN and DNTN both melt below 100 °C and have ambient vapor pressures comparable to TNT. While LC/MS was shown to be a viable technique for analysis of all three tetranitrate esters, only ETN was successfully analyzed by GC/MS. Performance of these nitrate esters as evaluated in lab using the small‐scale explosivity device (SSED) suggested RDX≫DNTN>PETN>ETN. Detonation velocities were calculated using Cheetah 6.0. Since the starting material is now widely available, it is likely that law enforcement will find ETN in future improvised explosive devices. This paper with its analytical schemes should prove useful in identification of this homemade explosive. 相似文献