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In recent years, unmanned aerial vehicle (UAV) technology has expanded to include UAV sprayers capable of applying pesticides. Very little research has been conducted to optimize application parameters and measure the potential of off-target movement from UAV-based pesticide applications. Field experiments were conducted in Raleigh, NC during the spring 2018 to characterize the effect of different application speeds and nozzle types on target area coverage and uniformity of UAV applications. The highest coverage was achieved with an application speed of 1 m s-1 and ranged from 30 to 60%, while applications at 7 m s-1 yielded 13 to 22% coverage. Coverage consistently decreased as application speed increased across all nozzles, with extended range flat spray nozzles declining at a faster rate than air induction nozzles likely due to higher drift. Experiments measuring the drift potential of UAV applications using extended range flat spray, air induction flat spray, turbo air induction flat spray, and hollow cone nozzles under 0, 2, 4, 7, and 9 m s-1 perpendicular wind conditions in the immediate 1.75 m above the target were conducted in the absence of natural wind in Raleigh, NC. Off-target movement was observed under all perpendicular wind conditions with all nozzles tested but was non-detectable beyond 5 m away from the target. Coverage from all nozzles exhibited a concave-shaped curve in response to the increasing perpendicular wind speed due to turbulence. The maximum target coverage in drift studies was observed when the perpendicular wind was 0 and 8.94 m s-1, but higher turbulence at the two highest perpendicular wind speeds (6.71 and 8.94 m s-1,) increased coverage variability while the lowest variability was observed at 2.24 m s-1 wind speed. Results suggested that air induction flat spray and turbo air induction flat spray nozzles and an application speed of 3 m s-1 provided an adequate coverage of target areas while minimizing off-target movement risk.
Feed represents a substantial proportion of production costs in the dairy industry and is a useful target for improving overall system efficiency and sustainability. The objective of this study was to develop methodology to estimate the economic value for a feed efficiency trait and the associated methane production relevant to Canada. The approach quantifies the level of economic savings achieved by selecting animals that convert consumed feed into product while minimizing the feed energy used for inefficient metabolism, maintenance and digestion. We define a selection criterion trait called Feed Performance (FP) as a 1 kg increase in more efficiently used feed in a first parity lactating cow. The impact of a change in this trait on the total lifetime value of more efficiently used feed via correlated selection responses in other life stages is then quantified. The resulting improved conversion of feed was also applied to determine the resulting reduction in output of emissions (and their relative value based on a national emissions value) under an assumption of constant methane yield, where methane yield is defined as kg methane/kg dry matter intake (DMI). Overall, increasing the FP estimated breeding value by one unit (i.e. 1 kg of more efficiently converted DMI during the cow’s first lactation) translates to a total lifetime saving of 3.23 kg in DMI and 0.055 kg in methane with the economic values of CAD $0.82 and CAD $0.07, respectively. Therefore, the estimated total economic value for FP is CAD $0.89/unit. The proposed model is robust and could also be applied to determine the economic value for feed efficiency traits within a selection index in other production systems and countries.
Following publication, errors were discovered in the y-axis labels of the electron and hole concentration plots in the following figure panels: figure 4c, figure 4d, figure 5c, figure 5d, figure 6c, figure 6d, figure 8c and figure 8d. The error does not affect the description, analysis or conclusions. The correct representation of the figure panels are shown here.
Englerophytum and Synsepalum are two closely related genera of trees and shrubs from the African tropics. Previous molecular studies have shown that these genera collectively form a clade within the subfamily Chrysophylloideae (Sapotaceae). However, little is known about the inter-relationships of the taxa within the Englerophytum–Synsepalum clade. In this study, nuclear ribosomal DNA and plastid trnH–psbA sequences were used to estimate the phylogeny within the clade. Results indicate that the clade consists of six major lineages, two composed solely of taxa from the genus Englerophytum and four composed of taxa from the genus Synsepalum. Each lineage can be distinguished by suites of vegetative and floral characters. Leaf venation patterns, calyx fusion, style length and staminodal structure were among the most useful characters for distinguishing clades. Some of the subclades within the Englerophytum–Synsepalum clade were also found to closely fit descriptions of former genera, most of which were described by Aubréville, that have since been placed in synonymy with Englerophytum and Synsepalum. The clade with the type species of Englerophytum also contains the type species of the genera Wildemaniodoxa and Zeyherella, which are confirmed as synonyms.
We have been using the technique of pulsed neutron powder diffraction to study several problems in the physics and chemistry of the actinide elements. In these elements one often encounters very complex structures resulting from polymorphic transformations presumably induced by the presence of 5f-electrons. For exampie, at least five distinct structures of plutonium metal are found between room temperature and its melting point of 640°C, and two of the structures are monoclinic! Single crystals are usually not available, and the high resolution which is intrinsic to the time-of-flight powder technique is a powerful tool in the solution of complex structural problems. The relatively low absorption coefficients for neutrons for at least some actinide isotopes is an advantage when surface oxidation is a problem (as in high-temperature experiments) and provides good particle statistics so that high-quality data are available for Rietveld refinement. The low absorption of neutrons by other materials such as vanadium and fused silica enables the use of these materials for the containment of samples in high- and low-temperature environments, and the fixed geometry of the time-of-flight technique simplifies the design of furnaces and cryostats.
Objectives: Individuals with moderate–severe traumatic brain injury (TBI) experience a transitory state of impaired consciousness and confusion often called posttraumatic confusional state (PTCS). This study examined the neuropsychological profile of PTCS. Methods: Neuropsychometric profiles of 349 individuals in the TBI Model Systems National Database were examined 4 weeks post-TBI (±2 weeks). The PTCS group was subdivided into Low (n=46) and High Performing PTCS (n=45) via median split on an orientation/amnesia measure, and compared to participants who had emerged from PTCS (n=258). Neuropsychological patterns were examined using multivariate analyses of variance and mixed model analyses of covariance. Results: All groups were globally impaired, but severity differed across groups (F(40,506)=3.44; p<.001; ŋp2 =.206). Rate of forgetting (memory consolidation) was impaired in all groups, but failed to differentiate them (F(4,684)=0.46; p=.762). In contrast, executive memory control was significantly more impaired in PTCS groups than the emerged group: Intrusion errors: F(2,343)=8.78; p<.001; ŋp2=.049; False positive recognition errors: F(2,343)=3.70; p<.05; ŋp2=.021. However, non-memory executive control and other executive memory processes did not differentiate those in versus emerged from PTCS. Conclusions: Executive memory control deficits in the context of globally impaired cognition characterize PTCS. This pattern differentiates individuals in and emerged from PTCS during the acute recovery period following TBI. (JINS, 2019, 25, 302–313)
Increasing evidence suggests that the presence of mobile ions in perovskite solar cells (PSCs) can cause a current–voltage curve hysteresis. Steady state and transient current–voltage characteristics of a planar metal halide CH3NH3PbI3 PSC are analysed with a drift-diffusion model that accounts for both charge transport and ion vacancy motion. The high ion vacancy density within the perovskite layer gives rise to narrow Debye layers (typical width ~2 nm), adjacent to the interfaces with the transport layers, over which large drops in the electric potential occur and in which significant charge is stored. Large disparities between (I) the width of the Debye layers and that of the perovskite layer (~600 nm) and (II) the ion vacancy density and the charge carrier densities motivate an asymptotic approach to solving the model, while the stiffness of the equations renders standard solution methods unreliable. We derive a simplified surface polarisation model in which the slow ion dynamics are replaced by interfacial (non-linear) capacitances at the perovskite interfaces. Favourable comparison is made between the results of the asymptotic approach and numerical solutions for a realistic cell over a wide range of operating conditions of practical interest.
There are many studies that show that breed, gender, age and feeding regime influence animal growth rate, meat yield and composition. These factors, together with slaughter and post-slaughter conditions, are thought to influence tenderness and flavour attributes of meat (Thompson, 2002)). Low variability is highly desirable and processes such as ‘A blueprint for improved consistent quality lamb’ (MLC, 1999) in the UK have attempted to improve the level and consistency of lamb eating quality. The purpose of this trial was to test whether the adoption of several key enhanced on–farm and in-abattoir practices led to improved eating quality throughout the lamb production season, especially for heavier, lean carcasses.
It is the practise for some farmers to supplement new season lambs with concentrates, often as a creep feed, in order to get them to market early before the price declines. This concentrate is usually based on cereals and would be high in n-6 fatty acids, diluting the beneficial effect of grass grazing which promotes the n-3 polyunsaturated fatty acid (PUFA) content in the meat (Fisher et al., 2000). The purpose of this trial was to assess the addition of linseed to the concentrate, fed in a creep-feed system, which would maintain or enhance the n-3 fatty acid composition of the meat of animals fed concentrates at grass during the finishing period (Cooper et al., 2004).
X-ray computed tomography (CT) measurements of live sheep have been used to predict carcass composition very accurately (Macfarlane et al., 2006). The utilisation of spiral CT scans (SCTS) for quantifying muscle volumes and weights, using automatic image analysis procedures has also been shown to be very accurate in sheep (Navajas et al., 2006). Although the limiting size of the CT gantry prevents CT scanning of live beef cattle, beef primal joints are small enough to be scanned. Hence, SCTS could be used to quantify beef carcass composition, and provide valuable information for breeding programmes including composition faster than by anatomical dissection. The objective of this study was to develop a CT image analysis procedure to assess fat, muscle and bone weights of beef carcasses and to evaluate its accuracy.
Nutritional recommendations to improve the human diet are to increase the P:S ratio and to decrease the n-6:n-3 ratio of food (Department of Health 1994). However, increasing the degree of unsaturation of meat lipids may alter the flavour of the cooked meat and can increase its susceptibility to oxidative changes such as lipid rancidity and colour deterioration. We have studied these quality aspects in meat from three breeds of lambs fed different fats.
Seventy two entire ram lambs of three genotypes were used in a 3x4 factorial design: Suffolk x Lleyn, Frieslands x Lleyn and Soay lambs were fed diets, for an average of 80 days, containing one of four fats at 50g/kg supplemented with 200 IU/kg vitamin E: 1, control, 2, linseed, 3, fish oil and 4, fish oil plus linseed (50:50). Sensory assessment was performed on loin chops grilled to an internal temperature of 74°C which were rated using 100mm unstructured line scales. For colour and lipid oxidation measurements, 10mm thick leg steaks were aged for 10 days in vacuum at 1°C then repacked in modified atmosphere (O2:CO2,75:25) and displayed under light at 4°C for 6 days.
The development of genetic markers and their application to farm animals has progressed rapidly, opening new prospects for identifying chromosomal regions that control quantitative traits (quantitative trait loci or QTL). However, there is less activity in QTL identification in sheep than in other livestock species. Surprisingly few QTL have been published for traits of direct relevance to sheep meat production, apart from studies of individual major genes such as the callipyge locus (Freking et al, 2002). This suggests there may be more QTL effects still to be found in sheep. Hence, this study aims to identify QTL for carcass composition and meat quality traits. This will provide a basis for targeting genomic regions to verify QTL in independent sheep populations.
The aim of future beef production is healthier, tastier products which consumers will find attractive. Combinations of breed and feeding system are required to fulfil these aims. In this project we compared the Holstein- Friesian (HF) breed, an allegedly inferior beef producer, with Welsh Black (WB), a traditional beef breed. Of particular interest was the role of polyunsaturated fatty acids (PUFA) in flavour development.
Thirty six steers, 18 HF and 18 WB, were reared on grass silage plus one of three concentrates. The concentrates contained different fat sources at 0.03 of intake: 1. megalac (control, C16:0); 2. formaldehyde-protected whole linseed (Lin, C18:3 n-3); and 3. an equal mix on a fat basis of protected linseed and fish oil (Lin/fish, C20:5 and C22:6 n-3). The animals were slaughtered after 90 days consumption of the diets. Fortyeight hours after slaughter, three forequarter muscles (M. supraspinatus, M. infraspinatus and M. triceps brachii caput longum) were trimmed of fat, minced and displayed in modified atmosphere packs (0.8 02:0.2 CO2, 4°C in 1000 Lux) for 3 or 10 days.
Selection objectives in sheep breeding are changing as the nature of the pressures upon the sheep industry change. Sheep breeders particularly need to address product quality traits, as these will determine consumer acceptance of lamb. Critical traits determining product quality are carcass composition and meat quality. New measurement technology, such as Computer Tomography (CT), offers the potential for more accurate measurement of carcass traits in the live animal and consequently improved genetic gains. On the other hand, meat quality traits pose particular problems for improvement, as measurement is generally restricted to the slaughtered animal. The present study was designed to investigate carcass composition (as measured by CT) and meat quality traits, determine the inheritance of these traits, relationships between them, and investigate the prediction of meat quality traits from CT measurements. At a later stage, these data will form the basis for QTL studies for carcass and meat quality traits.
Vitamin E protects the animal from oxidative stress in vivo and when it is administered at supranutritional levels it enhances the oxidative stability of meat. Studies have shown that poor absorption of vitamin E often occurs when concentrates are fed to lambs. Distribution of vitamin E in plasma, skeletal muscle, liver (short-term and fast release depot) and adipose tissue (long-term and slow release depot) provides useful information about the overall vitamin E status of the animals. This work studied the distribution of vitamin E in the tissues after supplementation in relation to diet and to the dietary level.
Under controlled experimental conditions, ruminally protected lipid supplements (PLS) rich in 18:2n-6 and 18:3n-3 have been successful in creating large shifts in the fatty acid composition of beef muscle (Scollan et al., 2003). However, there is a need to test methodology under commercial conditions and with a wider range of breed types. This study was conducted at a Yorkshire Farm and used Charolais Cross and the Stabiliser breed, a mix of 5 breeds designed to combine efficient production and good carcass quality.
This study aimed to compare the quality of beef from suckler bulls raised on a high-energy concentrate ration and slaughtered at different carcass weights (CW)/ages. In total, 42 spring-born, Charolais and Limousin-sired, weaned suckler bulls were provided with a finishing diet of ad libitum concentrates and grass silage until they reached target CW of 340, 380 and 420 kg. Intramuscular fat (IMF) content tended (P<0.06) to be higher for 420 kg CW than for 380 and 340 kg CW. Sensory tenderness was lower (P<0.001) for 420 kg CW than for 380 and 340 kg CW. Juiciness was higher (P<0.05) for 420 kg CW than for 380 kg CW. Flavour liking was higher (P<0.05) for 420 and 380 kg CW (which did not differ) than for 340 kg CW. Overall, an increase in CW resulted in a slight increase in IMF content which could be responsible for the increase in juiciness and flavour liking of the beef. An increase in CW led to a decrease in the tenderness of the beef even though the overall liking of the beef was not affected.
There are an estimated 1.5 million internally displaced persons (IDPs) in Ukraine because of the armed conflict in the east of the country. The aim of this paper is to examine utilisation patterns of mental health and psychosocial support (MHPSS) care among IDPs in Ukraine.
A cross-sectional survey design was used. Data were collected from 2203 adult IDPs throughout Ukraine between March and May 2016. Data on mental health care utilisation were collected, along with outcomes including post-traumatic stress disorder (PTSD), depression and anxiety. Descriptive and multivariate regression analyses were used.
PTSD prevalence was 32%, depression prevalence was 22%, and anxiety prevalence was 17%. Among those that likely required care (screened positive with one of the three disorders, and also self-reporting a problem) there was a large treatment gap, with 74% of respondents who likely required MHPSS care over the past 12 months not receiving it. For the 26% (N = 180) that had sought care, the most common sources of services/support were pharmacies, family or district doctor/paramedic (feldsher), neurologist at a polyclinic, internist/neurologist at a general hospital, psychologists visiting communities, and non-governmental organisations/volunteer mental health/psychosocial centres. Of the 180 respondents who did seek care, 163 could recall whether they had to pay for their care. Of these 163 respondents, 72 (44%) recalled paying for the care they received despite government care officially being free in Ukraine. The average costs they paid for care was US$107 over the previous 12 months. All 180 respondents reported having to pay for medicines and the average costs for medicines was US$109 over the previous 12 months. Among the 74% had not sought care despite likely needing it; the principal reasons for not seeking care were: thought that they would get better by using their own medications, could not afford to pay for health services or medications, no awareness of where to receive help, poor understanding by health care providers, poor quality of services, and stigma/embarrassment. The findings from multivariate regression analysis show the significant influence of a poor household economic situation on not accessing care.
The study highlights a high burden of mental disorders and large MHPSS treatment gap among IDPs in Ukraine. The findings support the need for a scaled-up, comprehensive and trauma-informed response to provision of MHPSS care of IDPs in Ukraine alongside broader health system strengthening.