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1.
It is increasingly acknowledged that homelessness involves more than just being without a house. Indeed, more recent definitions of what constitutes a home highlight the role of social connections and support (including, for example, access to space to engage in social relations). This study examined the role of secure housing and social support as predictors of psychological well-being of individuals following a period of homelessness. Using linear mixed models for longitudinal data, we investigated how changes in social support predicted changes in individuals’ self-reported personal well-being, life satisfaction and mood following a period of homelessness (n = 119), controlling for housing status, alcohol use and employment status. The results showed that remaining homeless predicted poorer personal well-being, life satisfaction and mood. In addition, changes in social support predicted well-being over and above housing stability. Implications of findings for policy and practice in the homeless sector are discussed.  相似文献   
2.
Hemorphins are known for their role in the control of blood pressure. Recently, we revealed the positive modulation of the angiotensin II (AngII) type 1 receptor (AT1R) by LVV-hemorphin-7 (LVV-H7) in human embryonic kidney (HEK293) cells. Here, we examined the molecular binding behavior of LVV-H7 on AT1R and its effect on AngII binding using a nanoluciferase-based bioluminescence resonance energy transfer (NanoBRET) assay in HEK293FT cells, as well as molecular docking and molecular dynamics (MD) studies. Saturation and real-time kinetics supported the positive effect of LVV-H7 on the binding of AngII. While the competitive antagonist olmesartan competed with AngII binding, LVV-H7 slightly, but significantly, decreased AngII’s kD by 2.6 fold with no effect on its Bmax. Molecular docking and MD simulations indicated that the binding of LVV-H7 in the intracellular region of AT1R allosterically potentiates AngII binding. LVV-H7 targets residues on intracellular loops 2 and 3 of AT1R, which are known binding sites of allosteric modulators in other GPCRs. Our data demonstrate the allosteric effect of LVV-H7 on AngII binding, which is consistent with the positive modulation of AT1R activity and signaling previously reported. This further supports the pharmacological targeting of AT1R by hemorphins, with implications in vascular and renal physiology.  相似文献   
3.
A new model that calculates the distribution of solar radiation inside a single-slope solar still has been proposed. In this model, the solar fraction on a vertical surface is divided into beam and diffuse parts and the optical view factors of surfaces inside the still are taken into account. To validate the model, outdoor tests of a conventional solar still were conducted under different weather conditions at the University of Strathclyde. The proposed model is compared with the previous one. It is found that the beam solar fraction is affected by both the geometry of the solar still and position of the sun in the sky. In contrast, the diffuse solar fraction is only dependent on the geometry of the solar distiller. The present model exhibited a lower root mean square error than that of the previous model. It appears that splitting the solar fraction into beam and diffuse parts improves the accuracy of modelling the performance of a single-slope solar still.  相似文献   
4.
This study aimed to evaluate intake, body growth, and the development of the rumen, mammary gland, and immune system in Holstein Friesian calves reared for 100 d on the commercially available feed FiberStart (conserved alfalfa, Medicago sativa; Fiber Fresh Feeds Ltd., Reporoa, New Zealand) and fed calf milk replacer (CMR) for either 56 or 91 d. Eighty calves (40 bulls and 40 heifer calves) were reared indoors in groups (n = 5 of the same sex/pen). All calves were fed 4 L of CMR/d (175 g/L of CMR) in 2 feeds/d for the first 10 d and then 1 feed/d until d 49 or 84. The calves were gradually weaned by d 56 (earlier weaned; n = 8 pens) and d 91 (later weaned; n = 8 pens). All calves were fed FiberStart ad libitum as the only solid feed source from d 1 to 100 of the study. Irrespective of treatment, all calves had similar body weights at d 0 (40.9 ± 3.0 kg) and d 49 (74.2 ± 5.1 kg) of the study. Calf sex had no effect on intake, growth, blood, and immune system parameters. Earlier-weaned calves consumed 18% more solid feed dry matter but had 16% lower body weight gain (28.9 vs. 38.5 kg, respectively) from d 56 to 100 relative to later-weaned calves, resulting in different body weight at 100 d (104 vs. 121 ± 1.3 kg). Although earlier-weaned calves could compensate for the loss of CMR dry matter and crude protein intake from d 56 to 100 by increasing forage intake, they were unable to compensate for the loss of energy from the CMR by increasing solid feed consumption. Plasma β-hydroxybutyrate concentrations were 52% greater in earlier-weaned calves than in later-weaned calves at d 84, indicating greater metabolic activity of the rumen wall. The duration of CMR feeding had no influence on humoral or cell-mediated immune functions of the calves, as evidenced by a lack of effect on antivaccine antibody responses as well as on immune gene expression. Earlier- versus later-weaned heifer calves had 5% lower mammary gland mass, indicating that greater energy supply increased mammary mass. The results of this experiment demonstrate the ability to artificially rear dairy calves on a conserved alfalfa as the only solid feed. Furthermore, earlier weaning off CMR promotes solid feed intake and an associated increase in blood β-hydroxybutyrate, an indicator of rumen development, but increasing the duration of CMR feeding improves growth and mammary gland mass by d 100. The implications of these findings on lifetime growth, health, and milk production in dairy heifers warrant further investigation.  相似文献   
5.
The principles and implementation of a phasor decomposition method for analyzing signals in tunable diode laser spectroscopy with wavelength modulation are described. This new technique enables recovery of the isolated and normalized residual amplitude modulation (RAM) signal from measured first harmonic signals at any chosen fundamental modulation frequency. Like the previously reported RAM technique, this new approach is absolute, yielding gas absorption line shape functions, concentrations and pressures without the need for calibration, under certain defined operating conditions. It represents an advancement of the RAM technique in that it obviates the need to operate at a specific high frequency to achieve phase quadrature between the RAM and derivative signals: the signals may be recovered at their maximum levels at any frequency. Measurements of the 1650.96 nm and the 1666.2 nm rotation/vibration absorption line shape functions for 1% and 10% methane in nitrogen at various pressures are compared to theoretical predictions derived from HITRAN data. The excellent agreement confirms the validity of the new technique. Further measurements of concentration and pressure confirm the efficacy of the technique for determining concentration in industrial process environments where the pressure may be unknown and changing. With the above features this new method is particularly suited to stand alone instrumentation for on-line deployment in industrial processes where the calibration factors in the conventional approach would present significant difficulties.  相似文献   
6.
The authors examined the effects of both general and task-specific writing experiences on college students' writing-skill development. On the basis of theories of expertise development and a cognitive process theory of writing-skill development, the authors predicted that repeated practice would be associated with superior writing skills and that after controlling for repeated practice, writing within a specific task domain would be associated with superior writing skills. Undergraduate students participated in a field experiment in which 279 students practiced their writing skills in a professionally relevant task domain, whereas another group of 385 students practiced their writing skills in a more general domain. The results were consistent with the predictions. The authors discuss implications for teaching writing skills and for general theories of expertise development in writing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Why is science difficult to learn? Things are seldom what they seem   总被引:9,自引:0,他引:9  
Abstract The difficulties of learning science are related to the nature of science itself and to the methods by which science is customarily taught without regard to what is known about children's learning. An information processing model is proposed to guide thinking and research in this area.  相似文献   
8.
A passive solar still with separate condenser has been modeled and its performance evaluated. The system has one basin (basin 1) in the evaporation chamber and two other basins (2 and 3) in the condenser chamber, with a glass cover over the evaporator basin and an opaque condensing cover over basin 3. Basins 1, 2 and 3 yield the first, second and third effects respectively. The top part of the condensing cover is shielded from solar radiation to keep the cover relatively cool. Water vapor from the first effect condenses under the glass cover while the remainder of it flows into the condenser, by purging and diffusion, and condenses under the liner of basin 2. The performance of the system is evaluated and compared with that of a conventional solar still under the same meteorological conditions. Results show that the distillate productivity of the present still is 62% higher than that of the conventional type. Purging is the most significant mode of vapor transfer from the evaporator into the condenser chamber. The first, second and third effects contribute 60, 22 and 18% of the total distillate yield respectively. It is also found that the productivity of the solar still with separate condenser is sensitive to the absorptance of the liner of basin 1, and the mass of water in basins 1 and 2. The mass of water in basin 3 and wind speed have marginal effect on distillate production. Other results are presented and discussed in detail.  相似文献   
9.
Wheatgerm is one of the main by‐products of the wheat milling industry, and is generally used for animal feed or oil production. With wheatgerm containing anywhere up to 14% oil, extraction of this oil via pressing and solvent extraction has had some success. The resulting oil is rich in the essential omega‐6 fatty acids and vitamin E, thus making it a speciality oil. The resulting stabilised de‐fatted wheatgerm has an increased protein content enabling it to be a very viable ingredient within the bakery and cereal industry.  相似文献   
10.
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