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The accelerating pace of climate change has led to unprecedented shifts in surface temperature and precipitation patterns worldwide, with African savannas being among the most vulnerable regions. Understanding the impacts of these extreme changes on ecosystem health, functioning and stability is crucial. This paper focuses on the detection of breakpoints, indicative of shifts in ecosystem functioning, while also determining relevant ecosystem characteristics and climatic drivers that increase susceptibility to these shifts within the semi‐arid to arid savanna biome. Utilising a remote sensing change detection approach and rain use efficiency (RaUE) as a proxy for ecosystem functioning, spatial and temporal patterns of breakpoints in the savanna biome were identified. We then employed a novel combination of survival analysis and remote sensing time series analysis to compare ecosystem characteristics and climatic drivers in areas experiencing breakpoints versus areas with stable ecosystem functioning. Key ecosystem factors increasing savanna breakpoint susceptibility were identified, namely higher soil sand content, flatter terrain and a cooler long‐term mean temperature during the wet summer season. Moreover, the primary driver of changes in ecosystem functioning in arid savannas, as opposed to wetter tropical savannas, was found to be the increased frequency and severity of rainfall events, rather than drought pressures. This research highlights the importance of incorporating wetness severity metrics alongside drought metrics to comprehensively understand climate–ecosystem interactions leading to abrupt shifts in ecosystem functioning in arid biomes. The findings also emphasise the need to consider the underlying ecosystem characteristics, including soil, topography and vegetation composition, in assessing ecosystem responses to climate change. While this research primarily concentrated on the southern African savanna as a case study, the methodological robustness of this approach enables its application to diverse arid and semi‐arid biomes for the assessment of climate–ecosystem interactions that contribute to abrupt shifts. [ABSTRACT FROM AUTHOR]

Various models and datasets related to aflatoxins in the maize and dairy production chain have been developed and used but they have not yet been linked with each other. This study aimed to investigate the impacts of climate change on aflatoxin B1 production in maize and its consequences on aflatoxin M1 contamination in dairy cow’s milk, using a full chain modelling approach. To this end, available models and input data were chained together in a modelling framework. As a case study, we focused on maize grown in Eastern Europe and imported to the Netherlands to be fed–as part of dairy cows’ compound feed–to dairy cows in the Netherlands. Three different climate models, one aflatoxin B1 prediction model and five different carryover models were used. For this particular case study of East European maize, most of the calculations suggest an increase (up to 50%) of maximum mean aflatoxin M1 in milk by 2030, except for one climate (DMI) model suggesting a decrease. Results from all combinations of carryover and climate models suggest a similar or slight increase (up to 0.6%) of the chance of finding aflatoxin M1 in milk above the EC limit of 0.05 μg/kg by 2030. Results varied mainly with the climate model data and carryover model considered. The model framework infrastructure is flexible so that forecasting models for other mycotoxins or other food safety hazards as well as other production chains, together with necessary input databases, can easily be included as well. This modelling framework for the first time links datasets and models related to aflatoxin B1 in maize and related aflatoxin M1 the dairy production chain to obtain a unique predictive methodology based on Monte Carlo simulation. Such an integrated approach with scenario analysis provides possibilities for policy makers and risk managers to study the effects of changes in the beginning of the chain on the end product. [ABSTRACT FROM AUTHOR]

Today, early weaning is more frequently applied by the modern pig breeder to obtain more litters per year. In addition, more and more European pig breeders apply a batch management system, which allows weaning to occur at fixed time points but entails that the offspring are treated at the litter level and not as individuals. Both evolutions might result in weaning lightweight piglets, which can cause, e.g., growth retardation of the offspring. Hence, the objective of this research was to improve the weaning weight of piglets of the same age by breeding with a highly conformed sire line. Therefore, a total of 23 sows were inseminated, 10 sows with semen of a well-conformed sire line (sire line B) and 13 sows with semen of a less conformed boar (sire line A). In total, 299 offspring were observed to monitor behavior, growth performance, and carcass characteristics. Subsequently, linear mixed models were developed to analyze the growth performance and carcass characteristics wherein only variables classified as significant (P < 0.05) were introduced as fixed factors. Results indicate that no significantly increased weaning weight could be accomplished by breeding with semen of sire line B. This could be due to the significant (P < 0.05) shorter gestation length of sows inseminated with semen of sire line B. However, the offspring of sire line B was defined by better carcass classification characteristics. Furthermore, this study presents that the mean birth weight of each piglet was significantly lower if a bigger litter size was recorded. When considering behavior, it was observed that piglets that did not seclude themselves from the litter had a significantly greater daily weight gain from birth to weaning compared to piglets that showed signs of isolation from the litter. A signifi- cantly greater daily gain from birth to slaughter was established for piglets with a greater birth weight. Also, results indicate that barrows had a significantly greater daily growth from weaning to slaughter than gilts. To conclude, this research determines that breeding with highly conformed sire lines does not improve the weaning weight of the offspring and thus cannot serve as a solution for early weaning. However, more research is required by performing more experiments with a greater number of boars and sows to confirm this result. In general, this study allows researchers to continue to improve and standardize the weaning weight of piglets of the same age. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between sound levels, pre-slaughter handling during loading and pork quality. Pre-slaughter variables were investigated from loading till slaughter. A total of 3213 pigs were measured 30 min post-mortem for pH 30LT ( M. Longissimus thoracis ). First, a sound level model for the risk to develop PSE meat was established. The difference in maximum and mean sound level during loading, mean sound level during lairage and mean sound level prior to stunning remained significant within the model. This indicated that sound levels during loading had a significant added value to former sound models. Moreover, this study completed the global classification checklist (Vermeulen et al., 2015a) by developing a linear mixed model for pH 30LT and PSE prevalence, with the difference in maximum and mean sound level measured during loading, the feed withdrawal period and the difference in temperature during loading and lairage. Hence, this study provided new insights over previous research where loading procedures were not included. [ABSTRACT FROM AUTHOR]

This study investigates whether rectal temperature of pigs, prior to slaughter, can give an indication of the risk of developing pork with PSE characteristics. A total of 1203 pigs were examined, measuring the rectal temperature just before stunning, of which 794 rectal temperatures were measured immediately after stunning. pH 30LT ( M. Longissimus thoracis ) and temperature of the ham (Temp 30Ham ) were collected from about 530 carcasses, 30 min after sticking. The results present a significant positive linear correlation between rectal temperature just before and after slaughter, and Temp 30Ham . Moreover, pH 30LT is negatively correlated with rectal temperature and Temp 30Ham . Finally, a linear mixed model for pH 30LT was established with the rectal temperature of the pigs just before stunning and the lairage time. This model defines that measuring rectal temperature of pigs just before slaughter allows discovery of pork with PSE traits, taking into account pre-slaughter conditions. [ABSTRACT FROM AUTHOR]

Environmental variables, as sound levels, were collected during the pre-slaughter process in 18 different Belgian commercial slaughterhouses. Four pre-slaughter phases were determined: firstly after arrival of the truck at the slaughterhouse and just before unloading, secondly during unloading, thirdly at lairage and finally while moving to the stunner. A total of 8508 pigs was examined during the pre-slaughter process, of which the pH LT ( M. longissimus thoracis ), at 30 min post-mortem was measured. For each pre-slaughter phase, variables which might influence pork quality were determined. Moreover, this study made it possible to infer a checklist to represent and predict PSE traits of pork for all kind of pre-slaughter situations. The checklist shows also that the impact on pork quality is more decisive for the variables measured close to the stunning phase. Hence, this information is useful for the industry to optimize handling of pigs, reducing the risk for PSE traits. [ABSTRACT FROM AUTHOR]

This study investigates whether sound levels above 85 dB(A), determined in literature as a critical sound level to induce stress in pigs, has also an effect on the pH of pork. Sound levels were recorded during pre-slaughter phases. A measure was taken after the arrival of the truck at the slaughterhouse, during unloading, lairage and just before stunning. The pH of the Longissimus thoracis or lumborum , 30 min after sticking (pH 30LT ) was measured. 8508 pigs were examined and the pH was measured on the carcasses. The results show that the cut-off value of 85 dB(A) during the pre-slaughtering phase is not only a threshold to evaluate animal welfare but can also be associated with a slower drop of pH if sound levels are < 85 dB(A). Finally a linear mixed model for pH 30LT was built with the sound level during lairage and the sound level prior to stunning as independent variables, having statistically the highest impact on pH 30LT of pork. [ABSTRACT FROM AUTHOR]

Objectives: Institutional Review Boards (IRBs) are charged with ensuring the protection of humans enrolled in research. IRB activities are governed by the United States Office for Human Research Protections, which does not clearly differentiate quality improvement from research. More clear standards are needed so that the protection of human subjects (including their right to privacy) can be ensured and health care providers can efficiently meet their objective of improving patient care through quality improvement efforts. While past commentaries on this subject have provided some guidance, no standard definitions exist that distinguish 'quality improvement' from 'research.'Methods: We conducted a national survey of IRBs serving academic medical centers to determine whether local guidelines exist that make this distinction, and if so, what criteria are used to guide decision making.Results: On the basis of the findings of our survey, we propose a decision algorithm to guide IRBs and quality improvement oversight committees as they define local policies that distinguish research projects from quality improvement efforts.Conclusions: The decision algorithm should result in greater ability to conduct quality improvement work in an efficient manner without compromising the protection of human subjects. The criteria identified are consistent with, but clearer than, the exemption standards provided in the common rule. [ABSTRACT FROM AUTHOR]

We have retrospectively analysed the sperm characteristics of 416 consecutive healthy young men who presented themselves in the past 19 years as candidate sperm donors. Ejaculate volume increased slightly (P = 0.067), and average sperm concentration decreased (P = 0.035) by 12.4×lO6ml over the observation period, so that sperm count per ejaculate remained unchanged (P = 0.91). In contrast, sperm morphology (r = −0.23, P < 0.0001), rapid progressive motility (r = −0.42, P < 0.0001) and total motility (r = −0.33, P < 0.0001) presented an important and time-related decrease. When a quadratic model was used rather than a linear one to analyse the data on rapid progressive motility, there appeared to have been no further decline since 1990. The average proportion of spermatozoa with normal morphology decreased from 39.2% in the period 1977–1980 to 26.6% in 1990–1995 (P < 0.0001), and the mean percentage of spermatozoa with rapid progressive motility decreased from 52.7 to 31.7% (P < 0.0001). The percentage of candidate donors with sperm characteristics below the 5th percentile cut-off value of a normal fertile population increased from 13 to 54% during the observation period (P < 0.0001). Since the technique of semen analysis has remained essentially unchanged in-so-far as has been practically possible, as has the method of recruitment of candidate sperm donors, the observed deterioration of sperm characteristics is considered to reflect degeneration of sperm production among men aged between 20 and 40 years. [ABSTRACT FROM PUBLISHER]

Since there is no gold standard for the diagnosis of immunological infertility, comparison between different methods and of their results with biological tests for the detection of antisperm antibodies must be used in defining the most reliable and clinically relevant method. We have evaluated the results of direct (n = 100) and indirect tests in serum (n = 140) and seminal plasma (n = 100) using the SpermMAR and Immunobead (IB) techniques for the detection of sperm antibodies of the immunoglobulin (Ig) classes G, A and M, and we have compared the results with those of the tray agglutination test and the adenosine triphosphate release cytotoxicity test. Results indicate the higher specificity and sensitivity of the SpermMAR results for IgG and IgA, as compared to the outcome of the IB test. It appears that the IB test for IgA may detect non-specific antibodies in serum. Little information is obtained from the tray agglutination test in seminal plasma, and the indirect SpermMar test for IgG in seminal plasma was the only independent variable associated with the outcome of the former test. Since the SpermMAR tests for IgG and IgA are more accurate and biologically relevant, as well as easier to perform than the respective IB tests, the former must be considered the method of first choice. [ABSTRACT FROM AUTHOR]

The results of the resazurin test (RES) and adenosine triphosphate (ATP) concentration in semen, measured by two methods, were compared for their ability to predict sperm parameters of semen samples from 42 subfertile men as assessed by a semi-computerized system. The highest correlation of RES grade was with sperm concentration (r = 0.70, P < 0.001), concentration of motile spermatozoa, concentration of motile spermatozoa with normal morphology and the ATP concentration using the reference LKB method (all r = 0.65, P < 0.001). The RES test has a positive predictive value of 93% for a progressive motile sperm concentration of 20 x 10(6)/ml or more, and a negative predictive power of 90% for the same variable at a criterion value of 10 x 10(6)/ml. The results of ATP measurement using the reference LKB and FireZyme methods presented a strong correlation (r = 0.74, P < 0.001). The correlations between ATP measurements from the FireZyme method and sperm characteristics were better than those obtained using the reference LKB method for ATP determination. It is concluded that the RES test can be performed with a relatively small volume of semen; it is easy to perform and requires not technical equipment. The accuracy and predictive value of this test are similar to more sophisticated ATP measurements. In addition, the RES may identify a subgroup of subfertile men with a decreased reducing capacity of semen. [ABSTRACT FROM AUTHOR]

Objectivity in assessing critical sperm characteristics such as concentration, motility and morphology, has been the target of many systems and devices. Methods based on physical principles such as turbidimetry, spectrophotometry, laser Doppler technology, are too imprecise or technically too complicated to be applied routinely in the laboratory. Microscopic images providing photographical, cinematographical or video data acquisition followed by manual or computer-assisted image analysis (CASA) suffer from practical and/or device deficiencies, making them tedious and time-consuming, or unreliable because of confounding factors and uncontrolled artefacts. A single-step computer system using visual evaluation of the microscopic field and manual tracking of sperm movement yields more reliable results, but technician expertise remains essential for correct performance. The scientific basis of multiple errors in semen aspiration, chamber quality, data acquisition and analysis is given. Biased interpretations of results or incorrect handling of statistical data are criticised. [ABSTRACT FROM AUTHOR]

Rapid developments have occurred in the management of couple infertility due to a male factor. These have stimulated renewed interest in semen analysis, which has become more correct, more reliable and more informative. The so-called basic semen analysis, which includes subjective estimation of sperm concentration, motility and morphology, has largely become obsolete. It has been replaced by several alternative techniques such as the home testing of semen by the man himself, the elaboration of methods and equipments for the exact assessment of conventional sperm characteristics, and the measurement of new parameters evaluating the functional state and capacity of spermatozoa, accessory sex glands and seminiferous epithelium. The present paper covers the following items: (i) conventional methods of semen analysis, (ii) the resazurin test and home fertility scoring, (iii) advanced methods for the objective assessment of conventional sperm characteristics and motility parameters. [ABSTRACT FROM AUTHOR]