1,861 research outputs found
What are the challenges facing the table egg industry in the next decades and what can be done to address them?
International audienceThere has been a strong consumer demand to take welfare into account in animal production, including table eggs. This is particularly true in Europe and North America but increasingly around the world. We review the main demands that are facing the egg industry driven by economic, societal and sustainability goals. We describe solutions already delivered by research and those that will be needed for the future. Already table egg consumption patterns have seen a major shift from cage to non-cage production systems because of societal pressures. These often feature free-range and organic production. These changes likely signal the future direction for the layer sector with the acceleration of the conversion of cage to barn and aviary systems with outdoor access. This can come with unintended consequences from bone fracture to increased disease exposure, all requiring solutions. In the near future, the laying period of hens will be routinely extended to improve the economics and environmental footprint of production. Many flocks already produce close to 500 eggs per hens in a lifetime, reducing the number of replacement layers and improving the economics and sustainability. It will be a challenge for scientists to optimize the genetics and the production systems to maintain the health of these hens. A major ethical issue for the egg industry is the culling of male day-old chicks of layer breeds as the meat of the males cannot be easily marketed. Much research has and will be devoted to alternatives. Another solution is elimination of male embryos prior to hatching by in ovo sexing approaches. The race to find a sustainable solution to early stage sex determination is on. Methods based on sex chromosomes, sexually dimorphic compounds and spectral properties of eggs containing male or female embryos, are being researched and are reviewed in this article. Other proposed solutions include the use of dual-purpose strains, where the males are bred to produce meat and the females to produce eggs. The dual-purpose strains are less efficient and do not compete economically in the meat or egg market; however, as consumer awareness increases viable markets are emerging. These priorities are the response to economic, environmental, ethical and consumer pressures that are already having a strong impact on the egg industry. They will continue to evolve in the next decade and if supported by a strong research and development effort, a more efficient and ethical egg-laying industry should emerge
Introducing an innovative surgical technique:gluteal turnover flap for posterior vaginal wall reconstruction :a case series
Four patients with rectal cancer required reconstruction of a defect of the posterior vaginal wall. All patients received neoadjuvant (chemo)radiotherapy, followed by an en bloc (abdomino)perineal resection of the rectum and posterior vaginal wall. The extent of the vaginal defect necessitated closure using a tissue flap with skin island. The gluteal turnover flap was used for this purpose as an alternative to conventional more invasive myocutaneous flaps (gracilis, gluteus, or rectus abdominis). The gluteal turnover flap was created through a curved incision at a maximum width of 2.5 cm from the edge of the perineal wound, thereby creating a half-moon shape skin island. The subcutaneous fat was dissected toward the gluteal muscle, and the gluteal fascia was incised. Thereafter, the flap was rotated into the defect and the skin island was sutured into the vaginal wall defect. The contralateral subcutaneous fat was mobilized for perineal closure in the midline, after which no donor site was visible.The duration of surgery varied from 77 to 392 min, and the hospital stay ranged between 3 and 16 days. A perineal wound dehiscence occurred in two patients, requiring an additional VY gluteal plasty in one patient. Complete vaginal and perineal wound healing was achieved in all patients. The gluteal turnover flap is a promising least invasive technique to reconstruct posterior vaginal wall defects after abdominoperineal resection for rectal cancer.</p
Prediction uncertainty assessment of a systems biology model requires a sample of the full probability distribution of its parameters
Multi-parameter models in systems biology are typically âsloppyâ: some parameters or combinations of parameters may be hard to estimate from data, whereas others are not. One might expect that parameter uncertainty automatically leads to uncertain predictions, but this is not the case. We illustrate this by showing that the prediction uncertainty of each of six sloppy models varies enormously among different predictions. Statistical approximations of parameter uncertainty may lead to dramatic errors in prediction uncertainty estimation. We argue that prediction uncertainty assessment must therefore be performed on a per-prediction basis using a full computational uncertainty analysis. In practice this is feasible by providing a model with a sample or ensemble representing the distribution of its parameters. Within a Bayesian framework, such a sample may be generated by a Markov Chain Monte Carlo (MCMC) algorithm that infers the parameter distribution based on experimental data. Matlab code for generating the sample (with the Differential Evolution Markov Chain sampler) and the subsequent uncertainty analysis using such a sample, is supplied as Supplemental Information
Effects of correcting metabolic acidosis on muscle mass and functionality in chronic kidney disease:a systematic review and meta-analysis
Metabolic acidosis unfavourably influences the nutritional status of patients with non-dialysis dependent chronic kidney disease (CKD) including the loss of muscle mass and functionality, but the benefits of correction are uncertain. We investigated the effects of correcting metabolic acidosis on nutritional status in patients with CKD in a systematic review and meta-analysis. A search was conducted in MEDLINE and the Cochrane Library from inception to June 2023. Study selection, bias assessment, and data extraction were independently performed by two reviewers. The Cochrane risk of bias tool was used to assess the quality of individual studies. We applied random effects meta-analysis to obtain pooled standardized mean difference (SMD) and 95% confidence intervals (CIs). We retrieved data from 12 intervention studies including 1995 patients, with a mean age of 63.7 ± 11.7 years, a mean estimated glomerular filtration rate of 29.8 ± 8.8 mL/min per 1.73 m2, and 58% were male. Eleven studies performed an intervention with oral sodium bicarbonate compared with either placebo or with standard care and one study compared veverimer, an oral HCl-binding polymer, with placebo. The mean change in serum bicarbonate was +3.6 mEq/L in the intervention group and +0.4 mEq/L in the control group. Correcting metabolic acidosis significantly improved muscle mass assessed by mid-arm muscle circumference (SMD 0.35 [95% CI 0.16 to 0.54], P < 0.001) and functionality assessed with the sit-to-stand test (SMD â0.31 [95% CI â0.52 to 0.11], P = 0.003). We found no statistically significant effects on dietary protein intake, handgrip strength, serum albumin and prealbumin concentrations, and blood urea nitrogen. Correcting metabolic acidosis in patients with CKD improves muscle mass and physical function. Correction of metabolic acidosis should be considered as part of the nutritional care for patients with CKD.</p
Lower striatal dopamine D2/3 receptor availability in obese compared with non-obese subjects
Background: Obesity is a result of a relative excess in energy intake over energy expenditure. These processes are controlled by genetic, environmental, psychological and biological factors. One of the factors involved in the regulation of food intake and satiety is dopaminergic signalling. A small number of studies have reported that striatal dopamine D-2/D-3 receptor [D2/3R] availability is lower in morbidly obese subjects. Methods: To confirm the role of D2/3R in obesity, we measured striatal D2/3R availability, using [I-123]IBZM SPECT, in 15 obese women and 15 non-obese controls. Results: Striatal D2/3R availability was 23% (p = 0.028) lower in obese compared with non-obese women. Conclusion: This study is an independent replication of the finding that severely obese subjects have lower striatal D2/3R availability. Our findings invigorate the evidence for lower striatal D2/3R availability in obesity and confirm the role of the striatal dopaminergic reward system in obesit
Are radiographs needed when MR imaging is performed for non-acute knee symptoms in patients younger than 45Â years of age?
Livestock grazing impacts components of the breeding productivity of a common upland insectivorous passerine:Results from a long-term experiment
The intensity of pastoral management in areas of High Nature Value farming is declining in some regions of Europe but increasing in others. This affects open habitats of conservation concern, such as the British uplands, where bird species that benefit from low-intensity grazing may be most sensitive to such polarization. While experimental manipulations of livestock grazing intensities have improved our understanding of upland breeding bird responses in the short term, none have examined the long-term impacts of altered management on reproductive success. Using a replicated landscape-scale experiment that started in 2003, we investigated the effects of four grazing treatments (intensive sheep; low-intensity sheep; low-intensity mixed sheep and cattle; and no grazing) on the breeding productivity of meadow pipits Anthus pratensis, the most common upland passerine. Surveys were carried out systematically during early (2003 and 2004) and late (2015 and 2016) sampling periods of the experiment to compare the short- and long-term effects of grazing treatments on breeding density and productivity of pipits specifically, but also on the overall bird community. Pipit breeding density was lowest under low-intensity sheep grazing while the highest egg-stage nest survival was observed in the same treatment, although no significant treatment effects were detected on overall nest survival or fledgling output. There were no significant differences in treatment effects between the sampling periods on any breeding variable, but overall nest survival was lower in the later sampling period across all treatments. Breeding bird species richness differed between treatments in the later sampling period, with highest species richness in the ungrazed treatment. Synthesis and applications. Livestock grazing management can have different outcomes for different upland birds. Our results showed that, with time, meadow pipit breeding productivity tended to be higher when sheep grazing intensity was reduced and/or mixed with cattle, and lower when livestock were removed, but not significantly so. Removal of grazing, however, can significantly increase bird species richness. The long-term experiment showed an overall decline in fledglings regardless of grazing treatments, potentially a result of increased predator numbers harboured by nearby developing woodland, highlighting the importance of considering wider landscape processes in grazing management decisions.</p
Response to âtraits and stress: keys to identify community effects of low levels of toxicants in test systemsâ by Liess and Beketov (2011)
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