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91.
Lanthanum-doped nano spinel ferrite compounds were synthesized via normal micelles method, characterized by means of TGA/DSC curves to know calcination temperature and stoichiometry of elements confirmed by EDAX. X-ray diffraction shows well defined cubic spinel structure with secondary phase of ortho ferrite LaFeO3. Lattice parameter exhibited gradual increases with increasing in La3+ ion concentrations due to the larger ionic radii of La3+ ions replace Fe3+ ions. FT-IR spectra recorded in the range of 4000–400 cm?1 to detect vibrational bands. Surface morphology analyzed by SEM, The particle size analyzed by Dynamic Light Scattering, full width half maxima of 311 peak obtained from XRD and TEM analysis, reveals that fine particle nature with little agglomeration and average particle size determined in the range of few nano meters.  相似文献   
92.
In this study, the room-temperature Charpy impact property of 3D-printed 15-5 stainless steel was investigated by a combined experimental and finite element modeling approach. The experimentally measured impact energy is 10.85 ± 1.20 J/cm2, which is comparable to the conventionally wrought and non-heat treated 15-5 stainless steel. In parallel to the impact test experiment, a finite element model using the Johnson–Cook material model with damage parameters was developed to simulate the impact test. The simulated impact energy is 10.46 J/cm2, which is in good agreement with the experimental data. The fracture surface from the experimentally tested specimen suggests that the 3D-printed specimens undergo predominately brittle fracture.  相似文献   
93.
This study used tests of content memory (item recognition of words and abstract designs), context memory (order recognition of verbal and nonverbal items), and working memory (recognition at a short retention interval) to examine patterns of performance in 27 schizophrenic patients, 52 chronic alcoholic patients, and 66 healthy control participants. When performance was age- and IQ-adjusted the schizophrenia group was significantly impaired in item and order recognition of verbal and nonverbal material; the alcoholic group was impaired only in order recognition for both material types. Item- and order-recognition deficits in the schizophrenia group were greatest at the shortest retention intervals, a pattern previously observed in patients with Parkinson's disease, suggesting a prominence of a working memory deficit in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
Insulin is one of the hormonal regulators of leptin synthesis and participates in adipose tissue maintenance. The present study was undertaken to clarify the association of endogenous insulin secretion and mode of therapy with body fat and serum leptin levels in diabetic subjects. We measured the fasting serum C-peptide level, as an estimate of endogenous insulin secretion, and the serum leptin level in 176 Japanese diabetic subjects (79 men and 97 women; age, 55.9+/-14.3 years; body mass index [BMI], 23.8+/-4.1 kg/m2 [mean+/-SD]). Thirty-one subjects were treated with diet therapy alone, 66 with sulfonylurea (SU), and 79 with insulin (including 29 with type I diabetes mellitus). Body fat was analyzed by the impedance method. Serum leptin levels significantly correlated with the BMI and body fat and were higher in women, mainly because of their greater body fat. Serum C-peptide concentrations positively correlated with body fat and serum leptin in subjects treated with diet and SU. In insulin-treated type II diabetic subjects, both serum C-peptide and the daily insulin dose were weakly associated with body fat and serum leptin. In those subjects, despite a lower percent body fat and body fat mass, serum leptin concentrations (10.3+/-8.4 ng/mL) were comparable to the levels in subjects treated with diet (8.8+/-8.5 ng/mL). When compared within the same BMI and body fat groups (BMI 20 to 25 and > 25 kg/m2) including the control subjects matched for age and sex, serum leptin levels were higher in insulin-treated type II diabetic subjects versus the control subjects and diabetic patients treated with diet or SU. Stepwise regression analysis for all of the diabetic subjects showed that both the serum C-peptide level and exogenous insulin administration, as well as the BMI, gender, and age, were determinants of the serum leptin level. In conclusion, endogenous insulin secretion is closely associated with body fat and serum leptin in diabetic subjects treated with diet therapy and SU. In Japanese insulin-treated type II diabetic subjects, both endogenous and exogenous insulin are associated with body fat and serum leptin, which is maintained at levels comparable to or somewhat higher than the levels in control subjects and diabetic patients treated without insulin.  相似文献   
95.
A prospective study of the pharmacokinetics of itraconazole solution was performed in 11 patients who underwent allogeneic BMT (day of BMT = day 0) after a conditioning regimen including total body irradiation (TBI). Itraconazole solution (400 mg once a day) was given 7 days before BMT and continued up to the end of neutropenia unless another antifungal treatment was necessary. Blood samples were collected before itraconazole intake (Cmin) and 4 h later (Cmax) every other day for assays of itraconazole (ITRA) and its active metabolite hydroxy-itraconazole (OH-ITRA). The mean values of Cmin ITRA and OH-ITRA, respectively, were 287 +/- 109 ng/ml and 629 +/- 227 ng/ml at day -1 and 378 +/- 147 ng/ml and 725 +/- 242 ng/ml at day +1. The maximum Cmin values were observed at day +3. Six patients at day -1 (54%) and 8 at day +1 (72%) had satisfactory residual plasma concentrations of at least 250 ng/ml of unchanged ITRA. From day +1 to day +9, eight patients discontinued the itraconazole treatment, five of them had satisfactory plasma residual concentrations at this time. This work shows a good bioavailability of itraconazole oral solution during the early phase after allogeneic BMT, but more data are needed for the late phases.  相似文献   
96.
Content in the digital form can be easily copied and distributed without permission of the owner. As a result, it is of paramount importance to protect content and deter illegal distribution using content protection mechanisms like embedding an imperceptible watermark into the content. Given that consumers want access to content from anywhere using any device, it is necessary to transcode content keeping in mind the limitations of the devices in terms of processing power and network connectivity. However, it is important that the watermark embedded in the content is preserved even after transcoding. The proposed approach embeds in a video, an imperceptible yet robust watermark which is resistant to transcoding. This approach focuses on the H.264 codec because of its widespread use in the industry.  相似文献   
97.
98.
Colossal magnetoresistive (CMR) materials with the compositional formula, Nd0.67A0.33MnO3 (where A = Ca, Sr, Ba, and Pb) in the nanocrystalline form were prepared by the PVA gel technique. After characterizing the samples structurally, a systematic investigation of magnetization has been undertaken, over a temperature range 10–300 K at 0.05 T magnetic field. An effort has been made to calculate the magnetocaloric behavior of all the samples theoretically using the experimental magnetization data. Other important parameters such as maximum entropy change, full width at half-maximum, relative cooling power, and maximum adiabatic temperature change under 0.05 T were also computed. The observed behavior has been explained qualitatively.  相似文献   
99.
A single quadrupole GC–MS method was optimized for multiresidue determination of 47 pesticides in grapes with limit of quantifications of each compound in compliance with the EU-MRL requirements. Sample preparation involved extraction of 10 g sample with 10 ml ethyl acetate (+10 g sodium sulphate) by homogenization at 15,000 rpm followed by centrifugation at 3000 rpm. The supernatant was cleaned by dispersive solid phase extraction with primary secondary amine and acidified with 0.1% formic acid. Residues were estimated in selected ion monitoring mode with programmable temperature vaporizer-large volume injection (8 μl). All the GC and MS parameters were thoroughly optimized to achieve satisfactory linearity (R2 > 0.99) within 0.01–0.25 mg kg−1 with minimum matrix interferences. Recoveries at 0.01 and 0.02 mg kg−1 were within 67–120% with associated precision RSD below 19%. The method was successfully applied for analysis of the real world samples for incurred residues.  相似文献   
100.
A truncated pyramid-type solar cooker is designed, fabricated and tested. The truncated pyramid geometry concentrates the incident light radiations towards the bottom and the glazing glass surface on the top facilitates the trapping of energy inside the cooker. One of the salient features of the proposed design is to completely eradicate the need for tracking the sun during cooking, as tracking of sun does not yield better performance. During testing, the highest plate stagnation temperature, under no-load condition, approached 140 °C and under full-load condition, water temperature inside the cooker reached 98.6 °C in 70 min. Two figures of merit, F1 and F2, were calculated and their values were 0.117° C m2/W and 0.467 °C l, respectively, meeting the standards prescribed by the Bureau of Indian Standards for solar box-type cookers. Minor modifications in design are recommended to achieve higher temperatures and reduce cooking times. The design also allows trays to be retained for use as a household dryer.  相似文献   
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