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41.
42.
The effectiveness of the mechanism of precipitation strengthening in metallic alloys depends on the shapes of the precipitates. Two different material systems are considered: tetragonal γ′′ precipitates in Ni-based alloys and tetragonal θ′ precipitates in Al-Cu-alloys. The shape formation and evolution of the tetragonally misfitting precipitates was investigated by means of experiments and phase-field simulations. We employed the method of invariant moments for the consistent shape quantification of precipitates obtained from the simulation as well as those obtained from the experiment. Two well-defined shape-quantities are proposed: (i) a generalized measure for the particles aspect ratio and (ii) the normalized λ2, as a measure for shape deviations from an ideal ellipse of the given aspect ratio. Considering the size dependence of the aspect ratio of γ′′ precipitates, we find good agreement between the simulation results and the experiment. Further, the precipitates’ in-plane shape is defined as the central 2D cut through the 3D particle in a plane normal to the tetragonal c-axes of the precipitate. The experimentally observed in-plane shapes of γ′′-precipitates can be quantitatively reproduced by the phase-field model.  相似文献   
43.

Objective

To survey the prevalence of cattle ticks in Nur County and prepare a list of tick fauna in this district.

Methods

This investigation was carried out on 150 head of cattle ticks of rural areas of Nur city which is located in Mazandaran province during spring and summer seasons of 2011. The collected ticks were identified using light microscope and available systematic keys.

Results

A total number of 1 563 ticks were isolated from examined cattle and their genus and numbers including: Ixodes ricinus 51% (111 male and 691 female) and Boophilus annulatus 49% (83 male and 678 female), respectively.

Conclusions

Results of the current investigation indicate the presence of two species of acarine ectoparasites which have potential health risk Ixodes ricinus and Boophilus annulatus. More studies are required to increase our data concerning ticks and other ectopreasites of ruminants in other areas of Mazandaran province and should be noted to their ability in transmission of infectious agents.  相似文献   
44.
A closed loop audit of the ear nose and throat(ENT) urgent referral clinic at a London hospital was conducted assessing the number of patients reviewed,referral source, appropriateness of referral, presenting complaint and assigned follow-up appointments. Data was sourced from clinic letters and the patient appointment system over a 3-mo period. The initial cycle analysed 490 patients and the subsequent cycle 396. The initial audit yielded clinically relevant and cost effective recommendations which were implemented, and the audit cycle was subsequently repeated. The reaudit demonstrated decreased clinic numbers from an average 9.8 to 7.2 patients per clinic, in keeping with ENT United Kingdom guidelines. A 21% decrease in patient follow-up and 13% decrease in inappropriate referrals was achieved. Direct bookings into outpatient clinics decreased by 8%, due to correct referral pathway utilisation. Comparisons of all data sets were found to show statistical significance P 0.05. We reported a total financial saving of £32490 in a period of 3 mo(£590 per clinic). We demonstrated that simple guidelines, supervision and consultant-led education which are nonlabour intensive can have a significant impact on service provision and cost.  相似文献   
45.
The aim of this study was to determine the correlation between thyroid hormones and lipid profile in blood of Iranian Moghani sheep in different ages and sexes. Blood samples were taken from the jugular vein of 260 clinically healthy and nonpregnant animals in eight age groups (1–14 days, 1–2, 2–3, 3–6, 6–12, 12–24, 24–48, and  > 48 months) in autumn. The plasma was analyzed to determine thyroxine (T4), triiodothyronine (T3), free thyroxine (fT4), free triiodothyronine (fT3), cholesterol, triglyceride, high-density lipoprotein (HDL-cholesterol), low-density lipoprotein (LDL-cholesterol) and very low-density lipoprotein (VLDL-cholesterol) concentrations. According to our data from Moghani sheep, an increase in age results in significant decreases in the plasma concentrations of T4, T3, fT4, fT3, cholesterol, and HDL-cholesterol (P < 0.05) but no gender-dependent significant differences in the studied parameters were found.  相似文献   
46.
The goal of the current study was to evaluate the efficiency of a phytotherapeutic intervention consisting of a combination of Nigella sativa and Vitex agnus-castus with citalopram in the control of hot flashes in healthy menopausal women. An 8 week, double-blind, randomized, placebo-controlled study was performed among 46 women aged between 40 and 60 years experiencing an average of more than four hot flashes per day recruited during July 2016 to June 2017. Data on severity of vasomotor symptoms were collected at the end of the eighth week. Herbal medication or placebo capsules were administered once daily in morning. At the end of the 8-week treatment period, analyses of covariance demonstrated the superiority of herbal combination with citalopram over placebo and citalopram for three MENQOL domain scores including vasomotor (p?<?.001), physical (p?=?.036), psychosocial (p?=?.001) but no significant differences were observed in terms of sexual function (p?=?.231). Based on the results, the addition of a combination of N. sativa and V. agnus-castus to the citalopram may be a potential clinical application for improving therapeutic outcomes. Larger randomized, controlled trials are also warranted for further investigations of these symptoms.  相似文献   
47.
48.
Lasers in Medical Science - This study was conducted to investigate the inhibitory effects of light-emitting diodes (LEDs) on exosome biogenesis and angiogenesis capacity in Ishikawa endometrial...  相似文献   
49.
50.
The present study sought to analyze a novel type of polymer membrane fuel cell to be used in vehicles. The performance of the fuel cell was evaluated by modeling the types of production–consumption heat in the anode and cathode (including half-reaction heat, activation heat, and absorption/desorption heat) and waterflood conditions. The meshing of flow channels was carried out by square cells and the governing equations were numerically discretized in the steady mode using the finite difference method followed by solving in MATLAB software. Based on the simulation results, the anodic absorption/desorption heat, anodic half-reaction heat, and cathodic activation heat are positive while the cathodic absorption/desorption heat and cathodic half-reaction heat show negative values. All heat values exhibit a decremental trend over the flow channel. Considering the effect of relative humidity, the relative humidity of the cathode showed no significant change while the anode relative humidity decreased along the flow channel. The velocity at the membrane layer was considerably lower, due to the smaller permeability coefficient of this layer compared to the gas diffusion and reactants (cathode) layers.  相似文献   
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