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The recent increased use of out-of-parlour feeders for dairy cows has occurred for two main reasons: (1) convenience, including ease of rationing and saving labour; and (2) claims made for beneficial responses in milk yield and/or milk composition. The suggestions concerning improvements in milk composition arise from the effects of the increased frequency of concentrate feeding on certain rumen parameters. There is a reduced fluctuation in those parameters, with a maintenance of ruminai acetate production, which gives beneficial effects on milk fat production. Evidence from the literature indicates that an increased frequency of concentrate feeding does not increase the proportion of milk fat (on a weight basis) but merely rectifies a decrease in milk fat caused by a high concentrate to forage ratio. In trials conducted over 2 years, two groups of cows were offered equal amounts of concentrates from either a controlled out-of-parlour concentrate feeder to provide frequent feeding (O), or twice daily in the parlour (P). Group O out-yielded group P (25.1 v. 23.9, s.e. of difference 0.32** and 27.1 v. 25.4, s.e. of difference 0.56** kg milk/day) in years 1 and 2, respectively. The milk fat content (g/kg) for group O was consistently lower than for group P (36.5 v. 38.1, s.e. of difference 0.91, P = 0.10; 39.8 v. 42.6, s.e. of difference 1.47, P = 0.15) but the difference was not significant. The solids-not-fat content (g/kg) was significantly higher for group O in year 1 (89.9 v. 89.1, s.e. of difference 0.18***) but similar for the two groups in year 2 (90.9 v. 90.9, s.e. of difference 0.60, NS). Overall, the yields of milk fat on the two treatments were similar but the yields of all other milk constituents were increased significantly with out-of-parlour feeding.
Xpert MTB/RIF (Xpert) is the preferred first-line test for all persons with tuberculosis (TB) symptoms in South Africa in line with a diagnostic algorithm. This study evaluates pre- and post-implementation trends in diagnostic practices for drug-sensitive, pulmonary TB in adults in an operational setting, following the introduction of the Xpert-based algorithm. We retrospectively analysed data from the national TB database for Greater Tzaneen sub-district, Limpopo Province. Trends in a number of cases, diagnosis and outcome and characteristics associated with death are reported. A total of 8407 cases were treated from 2008 until 2015, with annual cases registered decreasing by 31·7% over that time period (from 1251 to 855 per year). After implementation of Xpert, 69·9% of cases were diagnosed by Xpert, 29·4% clinically, 0·6% by smear microscopy and 0·1% by culture. Cases with a recorded microbiological test increased from 76·2% to 96·4%. Cases started on treatment without confirmation, but with a negative microbiological test increased from 7·1% to 25·7%. Case fatality decreased from 15·0% to 9·8%, remaining consistently higher in empirically treated groups, regardless of HIV status. Implementation of the algorithm coincided with a reduced number of TB cases treated and improved coverage of microbiological testing; however, a substantial proportion of cases continued to start treatment empirically.
The possibility that life, primitive or advanced, might exist in other places of the Universe has occupied the minds of scientists and lay-people for thousands of years. It is only in the last 25 years, however, that we have finally begun to search for answers to this profound question using experimental techniques. The goal of Astronomy is to understand the origin and evolution of planets, stars, galaxies and of the Universe as a whole. The appearance of life is an integral part of this whole process and our picture of the Universe will never be complete until we will comprehend also the significance of life in the process of Cosmic Evolution.
Using semi-empirical isochrones, we find the age of the Taurus star-forming region to be 3-4 Myr. Comparing the disc fraction in Taurus to young massive clusters suggests discs survive longer in this low density environment. We also present a method of photometrically de-reddening young stars using iZJH data.
Depressive symptoms are prominent psychopathological features of Huntington's disease (HD), making a negative impact on social functioning and well-being.
We compared the frequencies of a history of depression, previous suicide attempts and current subthreshold depression between 61 early-stage HD participants and 40 matched controls. The HD group was then split based on the overall HD group's median Hospital Anxiety and Depression Scale-depression score into a group of 30 non-depressed participants (mean 0.8, s.d. = 0.7) and a group of 31 participants with subthreshold depressive symptoms (mean 7.3, s.d. = 3.5) to explore the neuroanatomy underlying subthreshold depressive symptoms in HD using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI).
Frequencies of history of depression, previous suicide attempts or current subthreshold depressive symptoms were higher in HD than in controls. The severity of current depressive symptoms was also higher in HD, but not associated with the severity of HD motor signs or disease burden. Compared with the non-depressed HD group DTI revealed lower fractional anisotropy (FA) values in the frontal cortex, anterior cingulate cortex, insula and cerebellum of the HD group with subthreshold depressive symptoms. In contrast, VBM measures were similar in both HD groups. A history of depression, the severity of HD motor signs or disease burden did not correlate with FA values of these regions.
Current subthreshold depressive symptoms in early HD are associated with microstructural changes – without concomitant brain volume loss – in brain regions known to be involved in major depressive disorder, but not those typically associated with HD pathology.
Background: Clinical perfectionism is a transdiagnostic process that has been found to maintain eating disorders, anxiety disorders and depression. Cognitive behavioural models explaining the maintenance of clinical perfectionism emphasize the contribution of dichotomous thinking and resetting standards higher following both success and failure in meeting their goals. There has been a paucity of research examining the predictions of the models and motivation to change perfectionism. Motivation to change is important as individuals with clinical perfectionism often report many perceived benefits of their perfectionism; they are, therefore, likely to be ambivalent regarding changing perfectionism. Aims: The aim was to compare qualitative responses regarding questions about motivation to change standards and cognitions regarding failure to meet a personal standard in two contrasting groups with high and low negative perfectionism. Negative perfectionism refers to concern over not meeting personal standards. Method: A clinical group with a range of axis 1 diagnoses who were elevated on negative perfectionism were compared to a group of athletes who were low on negative perfectionism. Results: Results indicated that the clinical group perceived many negative consequences of their perfectionism. They also, however, reported numerous benefits and the majority stated that they would prefer not to change their perfectionism. The clinical group also reported dichotomous thinking and preferring to either keep standards the same or reset standards higher following failure, whilst the athlete group reported they would keep standards the same or set them lower. Conclusions: The findings support predictions of the cognitive behavioural model of clinical perfectionism.
We investigate the C-start escape response of larval fish by combining flow simulations using remeshed vortex methods with an evolutionary optimization. We test the hypothesis of the optimality of C-start of larval fish by simulations of larval-shaped, two- and three-dimensional self-propelled swimmers. We optimize for the distance travelled by the swimmer during its initial bout, bounding the shape deformation based on the larval mid-line curvature values observed experimentally. The best motions identified within these bounds are in good agreement with in vivo experiments and show that C-starts do indeed maximize escape distances. Furthermore we found that motions with curvatures beyond the ones experimentally observed for larval fish may result in even larger escape distances. We analyse the flow field and find that the effectiveness of the C-start escape relies on the ability of pronounced C-bent body configurations to trap and accelerate large volumes of fluid, which in turn correlates with large accelerations of the swimmer.
This theoretical study examines confined viscous planar jet/wake flows with continuous velocity profiles. These flows are characterized by the shear, confinement, Reynolds number and shear-layer thickness. The primary aim of this paper is to determine the effect of confinement on viscous jets and wakes and to compare these results with corresponding inviscid results. The secondary aim is to consider the effect of viscosity and shear-layer thickness. A spatio-temporal analysis is performed in order to determine absolute/convective instability criteria. This analysis is carried out numerically by solving the Orr–Sommerfeld equation using a Chebyshev collocation method. Results are produced over a large range of parameter space, including both co-flow and counter-flow domains and confinements corresponding to 0.1 < h2/h1 < 10, where the subscripts 1 and 2 refer to the inner and outer streams, respectively. The Reynolds number, which is defined using the channel width, takes values between 10 and 1000. Different velocity profiles are used so that the shear layers occupy between 1/2 and 1/24 of the channel width. Results indicate that confinement has a destabilizing effect on both inviscid and viscous flows. Viscosity is found always to be stabilizing, although its effect can safely be neglected above Re = 1000. Thick shear layers are found to have a stabilizing effect on the flow, but infinitely thin shear layers are not the most unstable; having shear layers of a small, but finite, thickness gives rise to the strongest instability.
In this theoretical study, a linear spatio-temporal analysis is performed on unconfined and confined inviscid jet/wake flows with surface tension in order to determine convective/absolute instability criteria. There is a single mode that is due to surface tension and many modes that are due to the jet/wake column. In the unconfined case, the full impulse response is considered in the entire outer flow. On the one hand, the surface tension mode propagates slowly in the cross-stream direction but dominates at the front and back of the wavepacket. On the other hand, the jet/wake column modes propagate more quickly in the cross-stream direction and therefore define the boundaries of the central region of the wavepacket. The flow is particularly unstable when these modes interact. For unconfined flows, it is found that at low and intermediate surface tensions the flow can be more absolutely unstable than that without surface tension but at high surface tensions the flow is stabilized. The effect of confinement has previously been studied but not with the inclusion of surface tension. Confinement and surface tension combined cause the transition from convective to absolute instability to occur even with significant coflow. This effect is examined over an infinite domain of density ratios and confinement.
Nasal swabs were taken from 492 babies born consecutively to residents of two South Wales towns soon after their discharge from maternity hospitals. Staphylococcus aureus was isolated from 352 babies (72%) and in 79 (22%) of these it was resistant to at least one antibiotic. By the time these babies were a year old the prevalence of both sensitive and resistant strains had fallen, so that only 12% still carried nasal staphylococci, but 64% of these organisms were then resistant to penicillin. Administration of penicillin to the baby seemed to be a more important factor in selecting resistant organisms than other antibiotics given to the baby, any antibiotic treatment to other members of the household, or discharge from hospital.
Menorrhagia can be treated by drug therapy or surgery. General practitioners (GPs) can prescribe drugs to reduce menstrual blood loss as first-line treatment, referring patients for surgical treatment if drug therapy fails. This study examined the efficacy of drugs used to treat menorrhagia and surveyed British GPs to discover the extent to which they prescribed the most effective drugs for this condition. The results suggest that treatment of this condition in primary care falls short of desirable standards. A meta-analysis of randomized trials of drug therapy revealed wide differences in efficacy and side effects. The most effective drug (tranexamic acid) is little used by British GPs, whereas the least effective drug (norethisterone) is the most frequently prescribed.
The anatomy and function of the oropharynx and larynx during deglutition can be assessed using the flexible endoscope, but this evaluation does not provide information on the oesophagus. Guided observation of oesophageal swallowing enables extended dysphagia evaluation.
To assess the diagnostic utility of guided observation of oesophageal swallowing in the evaluation of dysphagia.
Retrospective case series.
Procedures for guided observation of oesophageal swallowing were reviewed for oesophageal findings and compared with fluoroscopy and manometry.
Twenty-one patients underwent guided observation of oesophageal swallowing and concurrent videofluoroscopy and/or manometry. No complications of the former procedure occurred. The results of guided observation of oesophageal swallowing concurred with those of fluoroscopy in 15/21 cases (71 per cent) and with those of manometry in five of six (83 per cent) cases. Guided observation of oesophageal swallowing revealed anatomic pathology contributing to dysphagia in 15/21 (71 per cent) patients. The procedure identified pathology not detected by fluoroscopy and manometry in 13/21 (62 per cent) patients.
Guided observation of oesophageal swallowing appears to be a safe diagnostic tool with which to evaluate the oesophageal phase of deglutition.
A reliable grading system allows the clinician to classify disease severity, monitor progress and evaluate treatment efficacy. There is no currently accepted grading system for vocal process granuloma of the larynx.
To evaluate the reliability of a new grading system for vocal process granuloma.
All vocal process granuloma images from a digital laryngeal image library were abstracted. Granulomas were graded on a one to four system, as follows: grade one, sessile, non-ulcerative granuloma limited to vocal process; grade two, pedunculated or ulcerated granuloma limited to vocal process; grade three, granuloma extending past vocal process but not crossing midline of airway in fully abducted position; and grade four, granuloma extending past vocal process and past the midline of the airway in the fully abducted position. The granulomas were additionally graded A if unilateral and B if bilateral. Two laryngologists and two otolaryngology residents rated the granulomas on two separate occasions. Intra- and inter-observer reliability was evaluated with the kappa (κ) test statistic.
Thirty-five vocal process granulomas were identified. The percentage intra-observer agreement for the two laryngologists was 97 and 100 per cent (κ = 0.94 and 1.00, respectively). The percentage inter-observer agreement between the two laryngologists was 91 per cent (κ = 0.83). The percentage intra-observer agreement for the two residents was 89 and 91 per cent (κ = 0.83 and 0.77, respectively). The percentage inter-observer agreement between the two residents was 83 per cent (κ = 0.67).
The proposed grading system for vocal process granuloma displayed excellent intra- and inter-observer reliability among residents and experienced laryngologists.
We prospectively investigated whether organic food consumption by infants was associated with developing atopic manifestations in the first 2 years of life. The KOALA Birth Cohort Study in the Netherlands (n 2764) measured organic food consumption, eczema and wheeze in infants until age 2 years using repeated questionnaires. Diet was defined as conventional ( < 50 % organic), moderately organic (50–90 % organic) and strictly organic (>90 % organic). Venous blood samples taken from 815 infants at 2 years of age were analysed for total and specific IgE. Multivariate logistic regression models were fitted to control for potential confounding factors. Eczema was present in 32 % of infants, recurrent wheeze in 11 % and prolonged wheezing in 5 %. At 2 years of age, 27 % of children were sensitised against at least one allergen. Of all the children, 10 % had consumed a moderately organic diet and 6 % a strictly organic diet. Consumption of organic dairy products was associated with lower eczema risk (OR 0·64 (95 % CI 0·44, 0·93)), but there was no association of organic meat, fruit, vegetables or eggs, or the proportion of organic products within the total diet with the development of eczema, wheeze or atopic sensitisation. Further studies to substantiate these results are warranted.