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Limited availability of fish oils (FO), rich in omega-3 long-chain (≥C20) polyunsaturated fatty acids (FA), is a major constraint for further growth of the aquaculture industry. Long-chain omega-3 rich oils from crops genetically modified with algal genes are promising new sources for the industry. This project studied the use of a newly developed omega-3 canola oil (DHA-CA) in diets of Atlantic salmon fingerlings in freshwater. The DHA-CA oil has high proportions of the omega-3 FA 18:3n-3 and DHA and lower proportions of omega-6 FA than conventional plant oils. Levels of phytosterols, vitamin E, and minerals in the DHA-CA were within the natural variation of commercial canola oils. Pesticides, mycotoxins, polyaromatic hydrocarbons, and heavy metals were below lowest qualifiable concentration. Two feeding trials were conducted to evaluate effects of two dietary levels of DHA-CA compared to two dietary levels of FO at two water temperatures. Fish increased their weight approximately 20-fold at 16 °C and 12-fold at 12 °C during the experimental periods, with equal growth in salmon fed the FO diets compared to DHA-CA diets. Salmon fed DHA-CA diets had approximately the same EPA+DHA content in whole body as salmon fed FO diets. Gene expression, lipid composition, and oxidative stress related enzyme activities showed only minor differences between the dietary groups and the effects were mostly a result of dietary oil level, rather than the oil source. The results demonstrated that DHA-CA is a safe and effective replacement for FO in diets of Atlantic salmon during the sensitive fingerling life-stage.
Whether maternal obesity and gestational weight gain (GWG) are associated with early-childhood development in low-income, urban, minority populations, and whether effects differ by child sex remain unknown. This study examined the impact of prepregnancy BMI and GWG on early childhood neurodevelopment in the Columbia Center for Children’s Environmental Health Mothers and Newborns study. Maternal prepregnancy weight was obtained by self-report, and GWG was assessed from participant medical charts. At child age 3 years, the Psychomotor Development Index (PDI) and Mental Development Index (MDI) of the Bayley Scales of Infant Intelligence were completed. Sex-stratified linear regression models assessed associations between prepregnancy BMI and pregnancy weight gain z-scores with child PDI and MDI scores, adjusting for covariates. Of 382 women, 48.2% were normal weight before pregnancy, 24.1% overweight, 23.0% obese, and 4.7% underweight. At 3 years, mean scores on the PDI and MDI were higher among girls compared to boys (PDI: 102.3 vs. 97.2, P = 0.0002; MDI: 92.8 vs. 88.3, P = 0.0001). In covariate-adjusted models, maternal obesity was markedly associated with lower PDI scores in boys [b = −7.81, 95% CI: (−13.08, −2.55), P = 0.004], but not girls. Maternal BMI was not associated with MDI in girls or boys, and GWG was not associated with PDI or MDI among either sex (all-P > 0.05). We found that prepregnancy obesity was associated with lower PDI scores at 3 years in boys, but not girls. The mechanisms underlying this sex-specific association remain unclear, but due to elevated obesity exposure in urban populations, further investigation is warranted.
Six on-farm studies determined the effects of a rolled rye cover crop, herbicide program, and planting technique on cotton stand, weed control, and cotton yield in Georgia. Treatments included: (1) rye drilled broadcast with 19-cm row spacing and a broadcast-herbicide program (2) rye drilled with a 25-cm rye-free zone in the cotton row and a broadcast-herbicide program (3) rye drilled with a 25-cm rye-free zone in the cotton row with PPI and PRE herbicides banded in the cotton planting row, and (4) no cover crop (i.e., weedy cover) with broadcast herbicides. At two locations, cotton stand was lowest with rye drilled broadcast; at these sites the rye-free zone maximized stand equal to the no-cover system. At a third location, cover crop systems resulted in greater stand, due to enhanced soil moisture preservation compared with the no-cover system. Treatments did not influence cotton stand at the other three locations and did not differ in the control of weeds other than Palmer amaranth at any location. Treatments controlled Palmer amaranth equally at three locations; however, differences were observed at the three locations having the greatest glyphosate-resistant plant densities. For these locations, when broadcasting herbicides, Palmer amaranth populations were reduced 82% to 86% in the broadcast rye and rye-free zone systems compared with the no-cover system at harvest. The system with banded herbicides was nearly 21 times less effective than the similar system broadcasting herbicides. At these locations, yields in the rye broadcast and rye-free zone systems with broadcast herbicides were increased 9% to 16% compared with systems with no cover or a rye-free zone with PPI and PRE herbicides banded. A rolled rye cover crop can lessen weed emergence and selection pressure while improving weed control and cotton yield, but herbicides should be broadcast in fields heavily infested with glyphosate-resistant Palmer amaranth.
Currently no national guidelines exist for the management of scabies outbreaks in residential or nursing care homes for the elderly in the United Kingdom. In this setting, diagnosis and treatment of scabies outbreaks is often delayed and optimal drug treatment, environmental control measures and even outcome measures are unclear. We undertook a systematic review to establish the efficacy of outbreak management interventions and determine evidence-based recommendations. Four electronic databases were searched for relevant studies, which were assessed using a quality assessment tool drawing on STROBE guidelines to describe the quality of observational data. Nineteen outbreak reports were identified, describing both drug treatment and environmental management measures. The quality of data was poor; none reported all outcome measures and only four described symptom relief measures. We were unable to make definitive evidence-based recommendations. We draw on the results to propose a framework for data collection in future observational studies of scabies outbreaks. While high-quality randomised controlled trials are needed to determine optimal drug treatment, evidence on environmental measures will need augmentation through other literature studies. The quality assessment tool designed is a useful resource for reporting of outcome measures including patient-reported measures in future outbreaks.
Current scholarship offers conflicting conclusions about whether female candidates have a feminine advantage or a disadvantage. Previous work does not consider whether voters respond similarly to all types of messages that might emphasize feminine stereotypes, such as feminine trait and feminine issue messages. I argue that voters will respond differently to trait-based feminine messages relative to issue-based feminine messages. I test the effects of trait-based and issue-based feminine messages through two survey experiments. The results consistently show that emphasizing feminine traits harms female candidates, whereas emphasizing feminine issues helps female candidates. I use role congruity theory to argue that feminine traits activate feminine stereotypes about women, and feminine issues do not activate these stereotypes. I also show that trait-based and issue-based feminine messages affect Democratic and Republican female candidates in very different ways. These results have implications for the ability of women to win elected office and reverse the pervasive underrepresentation of women in politics.
Recent commercialization of auxin herbicide–based weed control systems has led to increased off-target exposure of susceptible cotton cultivars to auxin herbicides. Off-target deposition of dilute concentrations of auxin herbicides can occur on cotton at any stage of growth. Field experiments were conducted at two locations in Mississippi from 2014 to 2016 to assess the response of cotton at various growth stages after exposure to a sublethal 2,4-D concentration of 8.3 g ae ha−1. Herbicide applications occurred weekly from 0 to 14 weeks after emergence (WAE). Cotton exposure to 2,4-D at 2 to 9 WAE resulted in up to 64% visible injury, whereas 2,4-D exposure 5 to 6 WAE resulted in machine-harvested yield reductions of 18% to 21%. Cotton maturity was delayed after exposure 2 to 10 WAE, and height was increased from exposure 6 to 9 WAE due to decreased fruit set after exposure. Total hand-harvested yield was reduced from 2,4-D exposure 3, 5 to 8, and 13 WAE. Growth stage at time of exposure influenced the distribution of yield by node and position. Yield on lower and inner fruiting sites generally decreased from exposure, and yield partitioned to vegetative or aborted positions and upper fruiting sites increased. Reductions in gin turnout, micronaire, fiber length, fiber-length uniformity, and fiber elongation were observed after exposure at certain growth stages, but the overall effects on fiber properties were small. These results indicate that cotton is most sensitive to low concentrations of 2,4-D during late vegetative and squaring growth stages.
A prototype X-ray fluorescence system for chemical and phase microanalysis of materials has been developed and tested. Preliminary work with this system has indicated X-ray fluorescence detection limits on the order of 40 picograms for heavier elements such as gold when using a 100 micron collimator, 400 second counting time and a silver anode operating at 12 Kw. Phase identification by X- ray diffraction can be obtained from the same spot. A proposed design for an improved system providing greater elemental sensitivities and capable of semi-automated operation has been completed.
The use of high-intensity, 8Kw, x-ray sources (Rigaku rotating-anode generator and wide - angle goniometer for this study) provides both opportunities and challenges. With high - intensity x-ray sources, detection limits can be lowered significantly while still offering count times of practical duration. On the other hand, the availability of high intensity x-ray sources puts greater demands on information extraction procedures and on the mechanical preciseness of sample containment and support. In particular we addressed the use of a cylindrical aluminum sample cell with a 0.010’’ polycrystalline (cold rolled) beryllium window electron –beam welded to an aluminum frame. See Figure 1. This cell permitted analysis of various air-sensitive specimens. The sample was pressed against the back of the beryllium window by a spring-loaded backing plate.
Phase identification by X-ray diffraction techniques in a complex mixture would be greatly simplified if the component phases could be physically separated. As opposed to current computer search-match algorithms for phase identification, which presuppose a single diffraction scan on a carefully prepared sample, we propose multi-scan data-taking on a not-so-carefully prepared sample so as to exploit certain aberrations in the diffracted intensities. The result can effectively be a physical separation by diffraction. Examples include exploitation of samples having a preferentially oriented component as well as samples with components having differing crystallite sizes. The techniques can involve diffractometer as well as film techniques.
In powder diffraction experiments involving mixtures of compounds, identification of each individual phase is complicated by the presence of other phases. The interpretation of such complex patterns is often very difficult, and much effort has gone into computational search-match algorithms which attempt to identify individual phases (Nichols, 1966; Johnson, 1977; Frevel, 1976). The success achieved by these programs and by manual search-match methods accounts for the fact that X-ray diffractionists have, in the past, not actively searched for other techniques that could be used to simplify such complex problems. In a recent work (Nichols & Johnson, 1980), a comparison was made of the search-match methodologies employed by several similar technologies (mass spectroscopy, fingerprint identification, X-ray diffraction etc.). A significant observation was made that only in the X-ray method was there so much emphasis on analysis of phases in their “as received” condition. In the other cases, emphasis was placed on the separation of phases before obtaining the spectra. A classical example is the GC-MS instrument which employs a gas chromatograph to separate phases before the mass spectrographic analysis is carried out on what are, by that time, essentially pure phases.
The introduction of auxin herbicide weed control systems has led to increased occurrence of crop injury in susceptible soybeans and cotton. Off-target exposure to sublethal concentrations of dicamba can occur at varying growth stages, which may affect crop response. Field experiments were conducted in Mississippi in 2014, 2015, and 2016 to characterize cotton response to a sublethal concentration of dicamba equivalent to 1/16X the labeled rate. Weekly applications of dicamba at 35 g ae ha−1 were made to separate sets of replicated plots immediately following planting until 14 wk after emergence (WAE). Exposure to dicamba from 1 to 9 WAE resulted in up to 32% visible injury, and exposure from 7 to 10 WAE delayed crop maturity. Exposure from 8 to 10 and 13 WAE led to increased cotton height, while an 18% reduction in machine-harvested yield resulted from exposure at 6 WAE. Cotton exposure at 3 to 9 WAE reduced the seed cotton weight partitioned to position 1 fruiting sites, while exposure at 3 to 6 WAE also reduced yield in position 2 fruiting sites. Exposure at 2, 3, and 5 to 7 WAE increased the percent of yield partitioned to vegetative branches. An increase in percent of yield partitioned to plants with aborted terminals occurred following exposure from 3 to 7 WAE and corresponded with reciprocal decreases in yield partitioned to positional fruiting sites. Minimal effects were observed on fiber quality, except for decreases in fiber length uniformity resulting from exposure at 9 and 10 WAE.
During the summer of 2016, the Hawaii Department of Health responded to the second-largest domestic foodborne hepatitis A virus (HAV) outbreak in the post-vaccine era. The epidemiological investigation included case finding and investigation, sequencing of RNA positive clinical specimens, product trace-back and virologic testing and sequencing of HAV RNA from the product. Additionally, an online survey open to all Hawaii residents was conducted to estimate baseline commercial food consumption. We identified 292 confirmed HAV cases, of whom 11 (4%) were possible secondary cases. Seventy-four (25%) were hospitalised and there were two deaths. Among all cases, 94% reported eating at Oahu or Kauai Island branches of Restaurant Chain A, with 86% of those cases reporting raw scallop consumption. In contrast, a food consumption survey conducted during the outbreak indicated 25% of Oahu residents patronised Restaurant Chain A in the 7 weeks before the survey. Product trace-back revealed a single distributor that supplied scallops imported from the Philippines to Restaurant Chain A. Recovery, amplification and sequence comparison of HAV recovered from scallops revealed viral sequences matching those from case-patients. Removal of product from implicated restaurants and vaccination of those potentially exposed led to the cessation of the outbreak. This outbreak further highlights the need for improved imported food safety.
The phase-sensitive radio-echo sounder (pRES) is a powerful new instrument that can measure the depth of internal layers and the glacier bed to millimetre accuracy. We use a stationary 16-antenna pRES array on Store Glacier in West Greenland to measure the three-dimensional orientation of dipping internal reflectors, extending the capabilities of pRES beyond conventional depth sounding. This novel technique portrays the effectiveness of pRES in deriving the orientation of dipping internal layers that may complement profiles obtained through other geophysical surveying methods. Deriving ice vertical strain rates from changes in layer depth as measured by a sequence of pRES observations assumes that the internal reflections come from vertically beneath the antenna. By revealing the orientation of internal reflectors and the potential deviation from nadir of their associated reflections, the use of an antenna array can correct this assumption. While the array configuration was able to resolve the geometry of englacial layers, the same configuration could not be used to accurately image the glacier bed. Here, we use simulations of the performance of different array geometries to identify configurations that can be tailored to study different types of basal geometry for future deployments.
On 27 April 2015, Washington health authorities identified Escherichia coli O157:H7 infections associated with dairy education school field trips held in a barn 20–24 April. Investigation objectives were to determine the magnitude of the outbreak, identify the source of infection, prevent secondary illness transmission and develop recommendations to prevent future outbreaks. Case-finding, hypothesis generating interviews, environmental site visits and a case–control study were conducted. Parents and children were interviewed regarding event activities. Odds ratios (OR) and 95% confidence intervals (CI) were computed. Environmental testing was conducted in the barn; isolates were compared to patient isolates using pulsed-field gel electrophoresis (PFGE). Sixty people were ill, 11 (18%) were hospitalised and six (10%) developed haemolytic uremic syndrome. Ill people ranged in age from <1 year to 47 years (median: 7), and 20 (33%) were female. Twenty-seven case-patients and 88 controls were enrolled in the case–control study. Among first-grade students, handwashing (i.e. soap and water, or hand sanitiser) before lunch was protective (adjusted OR 0.13; 95% CI 0.02–0.88, P = 0.04). Barn samples yielded E. coli O157:H7 with PFGE patterns indistinguishable from patient isolates. This investigation provided epidemiological, laboratory and environmental evidence for a large outbreak of E. coli O157:H7 infections from exposure to a contaminated barn. The investigation highlights the often overlooked risk of infection through exposure to animal environments as well as the importance of handwashing for disease prevention. Increased education and encouragement of infection prevention measures, such as handwashing, can prevent illness.