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Global inequity in access to and availability of essential mental health services is well recognized. The mental health treatment gap is approximately 50% in all countries, with up to 90% of people in the lowest-income countries lacking access to required mental health services. Increased investment in global mental health (GMH) has increased innovation in mental health service delivery in LMICs. Situational analyses in areas where mental health services and systems are poorly developed and resourced are essential when planning for research and implementation, however, little guidance is available to inform methodological approaches to conducting these types of studies. This scoping review provides an analysis of methodological approaches to situational analysis in GMH, including an assessment of the extent to which situational analyses include equity in study designs. It is intended as a resource that identifies current gaps and areas for future development in GMH. Formative research, including situational analysis, is an essential first step in conducting robust implementation research, an essential area of study in GMH that will help to promote improved availability of, access to and reach of mental health services for people living with mental illness in low- and middle-income countries (LMICs). While strong leadership in this field exists, there remain significant opportunities for enhanced research representing different LMICs and regions.
Two-dimensional particle-in-cell (PIC) simulations have been used to investigate the interaction between a laser pulse and a foil exposed to an external strong longitudinal magnetic field. Compared with that in the absence of the external magnetic field, the divergence of proton with the magnetic field in radiation pressure acceleration (RPA) regimes has improved remarkably due to the restriction of the electron transverse expansion. During the RPA process, the foil develops into a typical bubble-like shape resulting from the combined action of transversal ponderomotive force and instabilities. However, the foil prefers to be in a cone-like shape by using the magnetic field. The dependence of proton divergence on the strength of magnetic field has been studied, and an optimal magnetic field of nearly 60 kT is achieved in these simulations.
Sodium and chloride are the key factors maintaining normal osmotic pressure (OSM) and volume of the extracellular fluid, and influencing the acid–base balance of body fluids. The experiment was conducted to investigate the effects of dietary Na+ and Cl− level on growth performance, excreta moisture, blood biochemical parameters, intestinal Na+–glucose transporter 1 (SGLT1) messenger RNA (mRNA), and Na+–H+ exchanger 2 (NHE2) mRNA, and to estimate the optimal dietary sodium and chlorine level for yellow-feathered chickens from 22 to 42days. A total of 900 22-day-old Lingnan yellow-feathered male chickens were randomly allotted to five treatments, each of which included six replicates of 30 chickens per floor pen. The basal control diet was based on corn and soybean meal (without added NaCl and NaHCO3). Treatments 2 to 5 consisted of the basal diet supplemented with equal weights of Na+ and Cl−, constituting 0.1%, 0.2%, 0.3% and 0.4% of the diets. Supplemental dietary Na+ and Cl− improved the growth performance (P<0.05). Average daily gain (ADG) showed a quadratic broken-line regression to increasing dietary Na+ and Cl− (R2=0.979, P<0.001), and reached a plateau at 0.1%. Supplemental Na+ and Cl− increased (P<0.05) serum Na+ and OSM in serum and showed a quadratic broken-line regression (R2=0.997, P=0.004) at 0.11%. However, supplemental Na+ and Cl− decreased (P<0.05) serum levels of K+, glucose (GLU) and triglyceride. Higher levels of Na+and Cl− decreased duodenal NHE2 transcripts (P<0.05), but had no effect on ileal SGLT1 transcripts. The activity of Na+ /K+-ATPase in the duodenum decreased (P<0.05) with higher levels of dietary Na+ and Cl−. In conclusion, the optimal dietary Na+ and Cl− requirements for yellow-feathered chickens in the grower phase, from 22 to 42 days of age, to optimize ADG, serum Na+, OSM, K+ and GLU were 0.10%, 0.11%, 0.11%,0.17% and 0.16%, respectively, by regression analysis.
This paper presents the work carried out to evaluate the benefits and performance impacts of introducing a hydrogen fuel cell powered electric taxiing system to a conventional short-haul aircraft. Tasks carried out in this research and reported in this paper include the initial system design, hydrogen tank initial sizing, calculation of the impact on fuel burn and emissions and the evaluation of the effects on Direct Operating Cost (DOC). The Airbus A320 has been selected as the datum aircraft for sizing the system, and the benefits analysis is particularly focused on the fleet composition and financial data of a Europe-based, low-cost, large-scale A320 family operator in 2016. The maximum power capacity of 400 kW has been sized based on the rolling friction coefficient of 0.02. Based on the operator’s 2016 financial, up to 1% fuel reduction can be achieved using the proposed system and the reduction in total maintenance cost is expected to be up to 7.3%. Additionally, up to 5.97% net profit improvement is estimated in comparison with the annual after-tax profit of the datum operator in 2016.
An experiment was conducted to determine the effects of supplementing different amounts of daidzein in a diet on the growth performance, blood biochemical parameters and meat quality of finishing beef cattle. Thirty finishing Xianan steers were distributed in three groups equilibrated by weight and fed three different dietary treatments (concentrate ratio = 80%): (1) control; (2) 500 mg/kg daidzein and (3) 1000 mg/kg daidzein, respectively. Steers were slaughtered after an 80-day feeding trial. Results showed that daidzein supplementation had no effect on the final body weight, average daily gain and feed conversion rate of steers. Steers fed with 1000 mg/kg daidzein had greater dry matter intake than those fed with control diets. Compared with the control group, the 1000 mg/kg daidzein group had a higher fat thickness, lower shear force and lightness. The pH, drip loss, cooking loss, redness (a*), yellowness (b*), moisture, ash, crude protein and intramuscular fat of the Longissimus dorsi muscle were unaffected by daidzein supplementation. Compared with the control group, the 1000 mg/kg daidzein group significantly increased the serum concentrations of insulin, free fatty acid and Glutamic-pyruvic transaminase. The 500 mg/kg daidzein group significantly increased the serum concentration of tetraiodothyronine compared with the control group. Supplemental daidzein did not affect the blood antioxidant ability and blood immune parameters in serum. In conclusion, daidzein supplementation above 500 mg/day modifies feed intake and metabolic and hormonal profile, with positive and negative effects on meat quality.
A multichannel calorimeter system is designed and constructed which is capable of delivering single-shot and broad-band spectral measurement of terahertz (THz) radiation generated in intense laser–plasma interactions. The generation mechanism of backward THz radiation (BTR) is studied by using the multichannel calorimeter system in an intense picosecond laser–solid interaction experiment. The dependence of the BTR energy and spectrum on laser energy, target thickness and pre-plasma scale length is obtained. These results indicate that coherent transition radiation is responsible for the low-frequency component (
1 THz) of BTR. It is also observed that a large-scale pre-plasma primarily enhances the high-frequency component (
3 THz) of BTR.
Heading date (HD) and flowering date (FD) are critical for yield potential and stability, so understanding their genetic foundation is of great significance in wheat breeding. Three related recombinant inbred line populations with a common female parent were developed to identify quantitative trait loci (QTL) for HD and FD in four environments. In total, 25 putative additive QTL and 20 pairwise epistatic effect QTL were detected in four environments. The additive QTL were distributed across 17 wheat chromosomes. Of these, QHd-1A, QHd-1D, QHd-2B, QHd-3B, QHd-4A, QHd-4B and QHd-6D were major and stable QTL for HD. QFd-1A, QFd-2B, QFd-4A and QFd-4B were major and stable QTL for FD. In addition, an epistatic interaction test showed that epistasis played important roles in controlling wheat HD and FD. Genetic relationships between HD/FD and five yield-related traits (YRTs) were characterized and ten QTL clusters (C1–C10) simultaneously controlling YRTs and HD/FD were identified. The present work laid a genetic foundation for improving yield potential in wheat molecular breeding programmes.
Hydrogen is an important intermediate that is produced during carbohydrate fermentation to volatile fatty acid and utilized by methanogens to produce methane in the rumen. Ruminal volatile fatty acid and dissolved methane concentrations are more than 500 times greater than dissolved hydrogen concentration. Therefore, we hypothesized that dissolved hydrogen might have a higher sensitivity in response to dietary changes compared with volatile fatty acid and dissolved methane. Using goats, we investigated the effects of increasing dietary starch content (maize replaced with wheat bran) and supplementing with rhubarb rhizomes and roots on the relationships among dissolved hydrogen, dissolved methane and other fermentation end products. The study was conducted in a replicated 4×4 Latin square with a 2×2 factorial arrangement of four treatments: two starch levels (220 v. 320 g/kg dry matter (DM)), without and with rhubarb supplement (0% v. 2.8% of total mixed ration). Increased dietary starch and rhubarb supplementation did not alter volatile fatty acid concentrations or methane emissions in terms of g/day, g/g DM intake and g/g organic matter digested. However, goats fed the high-starch diet had greater dissolved hydrogen (P=0.005) and relative abundance of Selenomonas ruminantium (P<0.01), and lower (P=0.02) copy number of protozoa than those fed the low-starch diet. Rhubarb increased ruminal dissolved H2 (P=0.03) and total volatile fatty acid concentration (P<0.001), but decreased copies of bacteria (P=0.002). In conclusion, dissolved hydrogen appears to be more sensitive to dietary changes with starch content and rhubarb supplementation, when compared with volatile fatty acid concentrations and methane production.
To investigate the morphology and dimensions of the vestibular aqueduct on axial, single-oblique and double-oblique computed tomography images.
The computed tomography temporal bone scans of 112 patients were retrospectively evaluated. Midpoint and opercular measurements were performed using axial, single-oblique and double-oblique images. Morphometric analyses were also conducted. The vestibular aqueduct sizes on axial, single-oblique and double-oblique images were compared.
At the midpoint, the mean (± standard deviation) vestibular aqueduct measured 0.61 ± 0.23 mm, 0.74 ± 0.27 mm and 0.82 ± 0.38 mm on axial, single-oblique and double-oblique images, respectively; at the operculum, the vestibular aqueduct measured 0.91 ± 0.30 mm, 1.11 ± 0.45 mm and 1.66 ± 1.07 mm on the respective images. The co-efficients of variation of the vestibular aqueduct measured at the midpoint were 37.4 per cent, 36.5 per cent and 47.5 per cent on axial, single-oblique and double-oblique images, respectively; at the operculum, the measurements were 33.0 per cent, 40.5 per cent and 64.5 per cent. Regarding morphology, the vestibular aqueduct was fissured (33.5 per cent), tubular (64.3 per cent) or invisible (2.2 per cent).
The morphology and dimensions of the vestibular aqueduct were highly variable among axial, single-oblique and double-oblique images.
β-Casomorphin is an opioid-like bioactive peptide derived from β-casein of milk that plays a crucial role in modulating animal’s feed intake, growth, nutrient utilization and immunity. However, the effect of β-casomorphin on lipid metabolism in chickens and its mechanism remain unclear. The aim of this study was to investigate the effects of β-casomorphin on fat deposition in broiler chickens and explore its mechanism of action. A total of 120 21-day-old Arbor Acres male broilers (747.94±8.85 g) was chosen and randomly divided into four groups with six replicates of five birds per replicate. Three groups of broilers were injected with 0.1, 0.5 or 1.0 mg/kg BW of β-casomorphin in 1 ml saline for 7 days, whereas the control group received 1 ml saline only. The results showed that subcutaneous administration of β-casomorphin to broiler chickens increased average daily gain, average daily feed intake and fat deposition, and decreased feed : gain ratio (P<0.05). The activity of malate dehydrogenase in the pectoral muscle, liver and abdominal adipose tissue was also increased along with the concentrations of insulin, very-low-density lipoprotein and triglyceride in the plasma (P<0.05). The activity of hormone-sensitive lipase in the liver and abdominal adipose tissue and the concentration of glucagon in the plasma were decreased by injection with β-casomorphin (P<0.05). Affymetrix gene chip analysis revealed that administering 1.0 mg/kg BW β-casomorphin caused differential expression of 168 genes in the liver with a minimum of fourfold difference. Of those, 37 genes are directly involved in lipid metabolism with 18 up-regulated genes such as very low density lipoprotein receptor gene and fatty acid synthase gene, and 19 down-regulated genes such as lipoprotein lipase gene and low density lipoprotein receptor gene. In conclusion, β-casomorphin increased growth performance and fat deposition of broilers. Regulation of fat deposition by β-casomorphin appears to take place through changes in hormone secretion and enzyme activities by controlling the gene expression of lipid metabolism and feed intake, increasing fat synthesis and deposition.
Pathogenesis of pregnancy toxemia (PT) is believed to be associated with the disruption of lipid metabolism. The present study aimed to explore the underlying mechanisms of lipid metabolism disorder in the livers of ewes with PT. In total, 10 pregnant ewes were fed normally (control group) whereas another 10 were subjected to 70% level feed restriction for 15 days to establish a pathological model of PT. Results showed that, as compared with the controls, the levels of blood β-hydroxybutyrate (BHBA), non-esterified fatty acids (NEFAs) and cholesterol were greater (P<0.05) and blood glucose level was lower (P<0.05) in PT ewes. The contents of NEFAs, BHBA, cholesterol and triglyceride were higher (P<0.05) and glycerol content was lower (P<0.05) in hepatic tissues of PT ewes than those of the controls. For ewes with PT, excessive fat vacuoles were observed in liver sections stained with hematoxylin–eosin; furthermore, inner structures of hepatocytes including nuclei, mitochondria and endoplasmic reticulum were damaged seriously according to the results of transmission electron microscope. Real-time PCR data showed that compared with the controls, the expression of hepatic genes involved in fatty acid oxidation (FAO) and triglyceride synthesis (TGS) was enhanced (P<0.05) whereas that related to acetyl-CoA metabolism (ACM) was repressed (P<0.05) in PT ewes. Generally, our results showed that negative energy balance altered the expression of genes involved in FAO, ACM and TGS, further caused lipid metabolism disorder in livers, resulting in PT of ewes. Our findings may provide the molecular basis for novel therapeutic strategies against this systemic metabolic disease in sheep.
Good canopy structure is essential for optimal maize (Zea mays L.) production. However, creating appropriate maize canopy structure can be difficult, because the characteristics of individual plants are altered by changes in plant age, density and interactions with neighbouring plants. The objective of the current study was to find a reliable method for building good maize canopy structure by analysing changes in canopy structure, light distribution and grain yield (GY). A modern maize cultivar (ZhengDan958) was planted at 12 densities ranging from 1.5 to 18 plants/m2 at two field locations in Xinjiang, China. At the silking stage (R1), plant and ear height increased with plant density as well as leaf area index (LAI), whereas leaf area per plant decreased logarithmically. The fraction of light intercepted by the plant (F) increased with increasing plant density, but the light extinction coefficient (K) decreased linearly from 0.61 to 0.39. Taking the optimum value of F (95%) as an example, and using measured values of K for each plant density at R1 and the equation from Beer's law, the corresponding (theoretical) LAI for each plant density was calculated and optimum plant density (9.72 plants/m2) obtained by calculating the difference between theoretical LAIs and actual observations. Further analysis showed that plant density ranging from 10.64 to 11.55 plants/m2 yielded a stable GY range. Therefore, taking into account the persistence time for maximum LAI, the plant density required to obtain an ideal GY maize canopy structure should be increased by 10–18% from 9.72 plants/m2.
The gastrointestinal tract (GIT) of animals is capable of sensing various kinds of nutrients via G-protein coupled receptor-mediated signaling transduction pathways, and the process is known as ‘gut nutrient chemosensing’. GPR40, GPR41, GPR43 and GPR119 are chemoreceptors for free fatty acids (FFAs) and lipid derivatives, but they are not well studied in small ruminants. The objective of this study is to determine the expression of GPR40, GPR41, GPR43 and GPR119 along the GIT of kid goats under supplemental feeding (S) v. grazing (G) during early development. In total, 44 kid goats (initial weight 1.35±0.12 kg) were slaughtered for sampling (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) between days 0 and 70. The expression of GPR41 and GPR43 were measured at both mRNA and protein levels, whereas GPR40 and GPR119 were assayed at protein level only. The effects of age and feeding system on their expression were variable depending upon GIT segments, chemoreceptors and expression level (mRNA or protein), and sometimes feeding system × age interactions (P<0.05) were observed. Supplemental feeding enhanced expression of GPR40, GPR41 and GPR43 in most segments of the GIT of goats, whereas G enhanced expression of GPR119. GPR41 and GPR43 were mainly expressed in rumen, abomasum and cecum, with different responses to age and feeding system. GPR41 and GPR43 expression in abomasum at mRNA level was greatly (P<0.01) affected by both age and feeding system; whereas their expression in rumen and abomasum at protein level were different, feeding system greatly (P<0.05) affected GPR41 expression, but had no effect (P>0.05) on GPR43 expression; and there were no feeding system×age interactions (P>0.05) on GPR41 and GPR43 protein expression. The expression of GPR41 and GPR43 in rumen and abomasum linearly (P<0.01) increased with increasing age (from days 0 to 70). Meanwhile, age was the main factor affecting GPR40 expression throughout the GIT. These outcomes indicate that age and feeding system are the two factors affecting chemoreceptors for FFAs and lipid derivatives expression in the GIT of kids goats, and S enhanced the expression of chemoreceptors for FFAs, whereas G gave rise to greater expression of chemoreceptors for lipid derivatives. Our results suggest that enhanced expression of chemoreceptors for FFAs might be one of the benefits of early supplemental feeding offered to young ruminants during early development.
We report on a novel processing route to prepare La0.8Ce0.2(Fe0.95Co0.05)11.8Si1.2/Cu bulk composites by low-temperature hot pressing. With increasing copper content, the compressive strength of the composites first decrease and then increase owing to the buffering effect of copper, but the magnetocaloric effect reduces to some extent. Copper addition improves the thermal conductivity of the composites, which compensates for the decrease in thermal conductivity due to porosity. A relatively large entropy change of 5.75–7.19 J/(kg K) at 2 T near the Curie temperature (249 K), good thermal conductivity of 7.51–15.55 W/(m·K), and improved compressive strength of 151.1–248.0 MPa make these composites attractive magnetic refrigeration materials.
Background: With advancements in technology, the use of video as a pedagogical method in medical education has gained in popularity, and may aid in teaching clinical skills. In the UBC MD program, videos have been used to assist in teaching the -neurological exam for several decades, but the currently available videos are outdated and not of contemporary quality. Methods: Drawing upon the cognitive theory of multimedia learning from Mayer and Moreno (2003) which describes methods to maximize learning by minimizing cognitive load, we developed a tool to systematically assess pedagogical videos. We inventoried twelve existing neurology videos and analyzed their use of methods such as weeding (removing extraneous information), signalling (visually highlighting important information), and chunking (grouping similar information together). Results: Generally, older videos had poor audiovisual quality that introduced extraneous load, while more current videos had higher production value, albeit inconsistent with the depth of their content. We therefore produced a new three-part neurological exam video series. We wrote storyboards, filmed with a focus on visually depicting the exam and findings, and edited to elucidate relevant physiological concepts. Conclusions: The end product has been adopted by the UBC MD program, and can be shared with other programs who may wish to adopt them.
Giant electromagnetic pulses (EMP) generated during the interaction of high-power lasers with solid targets can seriously degrade electrical measurements and equipment. EMP emission is caused by the acceleration of hot electrons inside the target, which produce radiation across a wide band from DC to terahertz frequencies. Improved understanding and control of EMP is vital as we enter a new era of high repetition rate, high intensity lasers (e.g. the Extreme Light Infrastructure). We present recent data from the VULCAN laser facility that demonstrates how EMP can be readily and effectively reduced. Characterization of the EMP was achieved using B-dot and D-dot probes that took measurements for a range of different target and laser parameters. We demonstrate that target stalk geometry, material composition, geodesic path length and foil surface area can all play a significant role in the reduction of EMP. A combination of electromagnetic wave and 3D particle-in-cell simulations is used to inform our conclusions about the effects of stalk geometry on EMP, providing an opportunity for comparison with existing charge separation models.
The present study evaluated the effects of isovalerate supplementation on the development of the small intestinal mucosa in dairy calves. Forty-eight Chinese Holstein bull calves at 15 days of age and 45.1 ± 0.36 kg of body weight were assigned randomly to four groups. The treatments were control, low-isovalerate, moderate-isovalerate and high-isovalerate with 0, 3, 6 and 9 g isovalerate per calf per day, respectively. The study comprised 75 days with a 15-day adaptation period followed by a 60-day sampling period. Calves were weaned at 60 days of age. Six calves were chosen from each treatment at random and slaughtered at 30 and 90 days of age. The small intestine morphology and activities of amylase and trypsin improved significantly with increasing age. No interaction between treatments and age was observed. The small intestine length, mucosa layer thickness, villus height and crypt depth increased linearly with increasing isovalerate supplementation. However, the ratio of villus height to crypt depth was not affected by treatment. Activities of amylase and trypsin increased linearly. The lactase activity increased linearly during the 75-day period and for pre-weaned calves but was unaltered for post-weaned calves. The relative mRNA expressions of growth hormone receptor, insulin-like growth factor-1 receptor and sodium-glucose co-transporter-1 in the small intestine mucosa increased linearly, and a similar pattern was observed for the expression of peptide transporter-1 in the duodenum and proximal jejunum. The results suggested that small intestine development was promoted by isovalerate in a dose-dependent manner.
In this paper, a new type of fixed-wing vertical take-off and landing, unmanned aerial vehicle (UAV) has been designed. Thrust-vector direct force control has been introduced in three axes to make UAV exhibit superior manoeuverability in transition flight. Considering the characteristics of UAV's dynamic model, which are non-linear, non-affine, and have redundant input, a two-stage progressive optimal control allocation method is developed, which can optimise position and attitude control in synthetical, and motivate effectors to generates desired force and moments. A task-oriented weight selection scheme is proposed to make objective function suitable for different tasks and flight conditions. In addition, a general constraint strategy is designed to guarantee the feasibility of optimal allocation results, which can largely reduce the onboard computation time. Simulations show that UAV can adjust flight attitude and use control effectors in an optimal way, and demonstrating satisfactory tracking of low-speed high-manoeuver flight paths.
The mammalian target of rapamycin (mTOR) has been shown to be involved in lipopolysaccharide (LPS)-induced immune responses in many mammal cells. Here, we suggest that the mTOR pathway is involved in the intestinal inflammatory responses evoked by LPS treatment in chicken embryos. The intestinal tissue from Specific pathogen free chick embryos was cultured in the presence of LPS for 2 h. Secretory immunoglobulin A (sIgA) concentrations, messenger RNA (mRNA) expression of cytokines, and protein levels of nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), mTOR and p70 ribosomal S6 kinase (p70S6K) were determined. The results showed that LPS treatment increased sIgA concentrations in a dose-dependent manner. The mRNA levels of interleukine (IL)-6, IL-8, IL-10, tumor necrosis factor-α and Toll-like receptor (TLR) 4 were upregulated by LPS treatment (P<0.05). Lipopolysaccharide increased the phosphorylation of Jun N-terminal kinase (JNK), p38 MAPK and NF-κB (P<0.05) while decreasing the phosphorylation level of mTOR (P<0.05). Supplementation of leucine at doses of 10, 20 and 40 mM dose-dependently decreased sIgA production. Leucine supplementation at 40 mM restored the phosphorylation level of mTOR and p70S6K while suppressing the phosphorylation levels of NF-κB (P<0.05) and partially down-regulating the phosphorylation of p38 MAPK and JNK. The transcription of IL-6 was significantly decreased by leucine supplementation. These results suggested that leucine could alleviate LPS-induced inflammatory responses by down-regulating NF-κB signaling pathway and evoking mTOR/p70S6K signaling pathway, which may involve in the regulation of the intestinal immune system in chicken embryos.