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Weeds can cause significant yield loss in watermelon production systems. Commercially acceptable weed control is difficult to achieve even with heavy reliance on herbicides. A study was conducted to evaluate a spring-seeded cereal rye cover crop with different herbicide application timings for weed management between row middles in watermelon production systems. Common lambsquarters and pigweed species (Palmer amaranth and smooth pigweed) densities and biomasses were often lower with cereal rye compared to no cereal rye, regardless of herbicide treatment. The presence of cereal rye did not negatively influence the number of marketable watermelon fruit, but average marketable fruit weight in cereal rye versus no cereal rye treatments varied by location. These results demonstrate that a spring-seeded cereal rye cover crop can help to reduce weed density and weed biomass, and potentially enhance overall weed control. Cereal rye alone did not provide full-season weed control, so additional research is needed to determine the best methods to integrate spring cover cropping with other weed management tactics in watermelon for effective full-season control.
A new constant contact pressure (CCP) indentation creep method is presented, which is based on keeping the mean contact pressure as defined through Sneddon’s hardness constant, until a steady-state strain rate is achieved. This is in contrast to the conventional constant load–hold (CLH) creep experiments, where the load is held constant and relaxation in both hardness and strain rate occurs at the same time. Besides controlling the mean contact pressure, the dynamic stiffness is furthermore used to assess the indentation depth, thereby minimizing thermal drift influence and pile-up or sink-in effects during long-term experiments. The CCP method has been tested on strain rate sensitive ultrafine-grained (UFG) CuZn30 and UFG CuZn5 as well as on fused silica, comparing the results with those of strain rate jump tests as well as the CLH nanoindentation creep tests. With the CCP method, strain rates from 5 × 10−4 s−1 down to 5 × 10−6 s−1 can be achieved, keeping the mean contact pressure constant over a long period of time, in contrast to the CLH method. The CCP technique thus offers the possibility of performing long-term creep experiments while retaining the contact stress underneath the tip constant.
Sheep production under extensive conditions is environmentally friendly but on upland pastures animals may not reach slaughter weight within one season. However, meat from older ‘hoggets’ will have different organoleptic properties to that from ‘young’ lambs which may affect its acceptability. Whilst prolonged grazing could intensify the highly acceptable flavours associated with grass consumption, which result from a high dietary intake of α-linolenic acid, prolonged fattening can produce less acceptable muttony flavours. Meat quality differences between lambs and hoggets have been compared in this trial by examining 8- and 20- month old Herdwick sheep, produced on grass fells in Cumbria and reputed to produce high quality meat. Grass-fed Suffolk crosses aged 6 months have been used as a control.
Evolutionary economics sees the economy as always in motion with change being driven largely by continuing innovation. This approach to economics, heavily influenced by the work of Joseph Schumpeter, saw a revival as an alternative way of thinking about economic advancement as a result of Richard Nelson and Sidney Winter's seminal book, An Evolutionary Theory of Economic Change, first published in 1982. In this long-awaited follow-up, Nelson is joined by leading figures in the field of evolutionary economics, reviewing in detail how this perspective has been manifest in various areas of economic inquiry where evolutionary economists have been active. Providing the perfect overview for interested economists and social scientists, readers will learn how in each of the diverse fields featured, evolutionary economics has enabled an improved understanding of how and why economic progress occurs.
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 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.
To estimate the prevalence of underweight and overweight among Bangladeshi adults and to determine if the double burden of underweight and overweight differs by gender and other socio-economic characteristics of individuals.
We used data from the Bangladesh Demographic and Health Survey 2011. Multinominal logistic regression was used to examine associations between the different nutritional statuses of individuals and related determinants. Interaction effect was checked between gender and various socio-economic factors.
Nationwide, covering the whole of Bangladesh.
Individuals aged >18 years (women, n 16 052; men, n 5090).
Underweight was observed among 28·3 % of men and 24·4 % of women, whereas overweight was observed among 8·4 % of men and 16·9 % of women. The odds of being overweight were significantly lower among urban men (OR=0·46; 95 % CI 0·37, 0·57) compared with urban women, whereas the odds of being underweight were significantly higher among urban men (OR=1·33; 95 % CI 1·07, 1·64) compared with urban women. The odds of being overweight were lower among higher educated men (OR=0·48; 95 % CI 0·39, 0·58) and men of rich households (OR=0·45; 95 % CI 0·37, 0·54) compared with higher educated women and women of rich households, respectively.
There are important gender differences in the prevalence of underweight and overweight among the adult population in Bangladesh. Women with higher education, in rich and urban households have higher chances of being overweight and lower chances of being underweight compared with their male counterparts.
Constitutive equations, based on continuum mechanics and representing behavior of a mixture of two elastic solids, can be used for modeling of materials such as particulate composites. In this study, the behavior of continuum of a mixture occupying half-space under axisymmetric loads is calculated using Fourier and Hankel transform methods. For this purpose, Love's strain functions are used and the general solution of problem under proper boundary conditions is presented. By applying the results obtained to the sinusoidal distributed vertical load and Boussinesq problems that require the use of Cartesian and cylindrical coordinate systems, displacement vectors, diffusive force vector and components of stress tensors are calculated. At the end of the study, the experimental results of a special particulate composite are used to check the accuracy of the solutions obtained.
Objective: Multiple system atrophy (MSA) is an incurable neurodegenerative illness in which progressive symptoms, including stridor and acute laryngeal obstruction, occur. Advanced care planning and palliative care discussions in people living with MSA are not well defined. The aim of the present study is to evaluate advanced care planning and current practices in palliative care in MSA to identify opportunities for improving quality of care. Methods: The study is a retrospective chart review assessing the focus and timing of palliative care discussions in people living with MSA. Some 22 charts were reviewed. Results: A total of 22 patients were included. The most common symptoms were parkinsonism, orthostatic hypotension, GI/GU dysfunction, ataxia and gait impairment. Six patients had stridor. Of the palliative care discussions that took place, the most common topics were diagnosis, symptoms or symptom management, and prognosis. In the majority of patients who died and who had a do-not-attempt-resuscitation order, discussions surrounding resuscitation and goals of care took place only hours before death. Conclusions: There is no standard approach to advanced care planning and palliative care discussions in people living with MSA. We propose a framework to guide advanced care planning and palliative care discussions in MSA.
Massive stars provide most of our current knowledge of the first star forming galaxies in the universe via their ultraviolet and optical spectra redshifted into the visible and near-infrared bands. Here I briefly review the growing body of data on these early stellar populations from which star formation rates, the initial mass function, chemical abundances, ages, and dust reddenings are being deduced. New evidence also shows the dramatic impact which massive stars have on their galactic and intergalactic environments.
Low frequency radio astronomy for the purpose of this discussion is defined as frequencies ≲100 MHz. Since the technology is fairly simple at these frequencies and even Jansky’s original observations were made at 20.5 MHz, there have been many years of research at these wavelengths. However, though radio astronomers have been working at low frequencies since the first days of science, the observing limitations and the move of much of the effort to ever shorter wavelengths has meant that most areas still remain to be fully exploited with modern techniques and instruments. In particular, the possibilities for pursuing the very lowest frequencies by interferometry of ground to space, in Earth orbit, or from the Moon promises a rebirth of work in this wavelength range.
We present concepts for space-ground VLBI and a fully space-based array in high Earth orbit to pursue the astrophysics which can only be probed at these frequencies. An Orbiting Low Frequency Radio Astronomy Satellite (OLFRAS) and a Low Frequency Space Array (LFSA) are two concepts which will open this last, poorly explored area of astronomy at relatively low cost and well within the limits of current technology.
The anatomy of Crenella decussata (Mytiloidea) is described. Individuals of this circumboreal species occupy granular crypts composed of sand grains held in place by mucus. The swollen basal region of the tubule is occupied by an individual, which connects to the sediment surface by two posterior tubes accommodating the inhalant and exhalant streams. There is reduction in musculature and, most importantly, anterior foreshortening of the outer ctenidial demibranchs and loss of the labial palps. This creates an anterior space in the mantle for the initial brooding of fertilized ova by females to the prodissoconch stage. Subsequently, these larvae are transferred to the exhalant tube of the crypt wherein they attach by a single fine byssal thread and are further brooded until the crawl-away juvenile stage is attained. Experimental studies of larval behaviour suggest that parental pheromones sustain the female/offspring bond. Newly hatched individuals responded to parental exhalant water by actively attaching themselves using a byssal thread. This response persisted for 28 days, but not after 55 days when, we suggest, the pheromonal response ceases and offspring are developed sufficiently to take up life in their own nests. Offspring retrieved from parental crypts and fed continuously reached an average shell length of 500 μm after 7.5 months. Brooded offspring thus appear to rely on embryonal energy resources until post-metamorphosis, after which suspension feeding becomes essential for further growth and development before the parental crypt is vacated.
Porous ceramics have been widely used under extreme environments due to their high strength, good thermal shock resistance, and excellent corrosion resistance. Recently, silicon aluminum oxynitride (SiAlON) ceramic, a solid solution of Si3N4 with AlN, SiO2, and Al2O3, attracted our interest because of its superior mechanical and physical properties for applications under extreme environments (i.e., high temperature, high pressure, excellent mechanical wear, and low PH). However, in spite of its many unique properties, porous SiAlON production has not been scaled up sufficiently to meet industrially relevant quantities due to its high synthesis cost and the difficulty of manufacturing articles. Here, we report on a scalable two-step carbothermal reduction and nitridation (CRN) method to synthesize mechanically robust SiAlON ceramic materials with controlled porosity levels. The morphologies and chemical composition of the synthesized porous SiAlON ceramics were characterized using SEM, XRD, EDAX, and microprobe analysis. In addition, the flexural strength of the engineered porous SiAlON ceramics is also reported in this paper.
The spectrum of the supergiant FG Sge has been studied from a series of high dispersion 120-in. coudé spectrograms obtained during the interval 1969–72, thus continuing the work of Herbig and Boyarchuk (1968). The star, of effective temperature about 6500 K in 1972, is cooling at the rate of 250 K yr-1; it is known to have ejected a still visible planetary nebula some 6000 years ago (Flannery and Herbig, 1973). Abnormally strong absorption lines of Y ii, Zr ii, Ce ii, La iiand other s-process species began to appear in the spectrum of the central star some time after 1967 and have progressively strengthened. Present abundances per gram of these elements are about 25 times the solar value. There is little doubt that the atmosphere of the star has been enriched in these elements during the past seven years, but the rate of enrichment now appears to be slowing down.