1,460 research outputs found

    Environmental effects on progesterone profile measures of dairy cow fertility

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    Environmental effects on fertility measures early in lactation, such as the interval from calving to first luteal activity (CLA), proportion of samples with luteal activity during the first 60 days after calving (PLA) and interval to first ovulatory oestrus (OOE) were studied. In addition, traditional measurements of fertility, such as pregnancy to first insemination, number of inseminations per service period and interval from first to last insemination were studied as well as associations between the early and late measurements. Data were collected from an experimental herd during 15 years and included 1106 post-partum periods from 191 Swedish Holsteins and 325 Swedish Red and White dairy cows. Individual milk progesterone samples were taken twice a week until cyclicity and thereafter less frequently. First parity cows had 14.8 and 18.1 days longer CLA (LS-means difference) than second parity cows and older cows, respectively. Moreover, CLA was 10.5 days longer for cows that calved during the winter season compared with the summer season and 7.5 days longer for cows in tie-stalls than cows in loose-housing system. Cows treated for mastitis and lameness had 8.4 and 18.0 days longer CLA, respectively, compared with healthy cows. OOE was affected in the same way as CLA by the different environmental factors. PLA was a good indicator of CLA, and there was a high correlation (−0.69) between these two measurements. Treatment for lameness had a significant influence on all late fertility measurements, whereas housing was significant only for pregnancy to first insemination. All fertility traits were unfavourably associated with increased milk production. Regression of late fertility measurements on early fertility measurements had only a minor association with conception at first AI and interval from first to last AI for cows with conventional calving intervals, i.e. a 22 days later, CLA increased the interval from first to last insemination by 3.4 days. Early measurements had repeatabilities of 0.14–0.16, indicating a higher influence by the cow itself compared with late measurements, which had repeatabilities of 0.09–0.10. Our study shows that early fertility measurements have a possibility to be used in breeding for better fertility. To improve the early fertility of the cow, there are a number of important factors that have to be taken into account

    Can the microbiome drive the suppression of grapevine trunk diseases?

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    Grapevine trunk diseases (GTDs), caused by several fungal species, are among the most destructive grapevine diseases in New Zealand and other grape-growing countries. The control of the diseases is problematic, and there is currently no approved fungicide for their eradication. This has necessitated seeking alternative strategies, including a sustainable biological control approach, to manage the diseases. Therefore, this study aimed to identify taxa in the grapevine microbiome that contribute to plant health. In some New Zealand vineyards, observations have revealed vines that remain healthy within a background of trunk diseases. These grapevines were termed ‘disease-escape’ to represent their apparent health under heavy disease pressure. Recent research on the grapevine microbiome has shown that microorganisms from these ‘disease-escape’ plants could contribute to disease suppression. Putative disease escape vines were identified in vineyards in two grape-growing regions in New Zealand: Hawke’s Bay and Canterbury. The vines were selected based on their presence in a diseased area, maturity, and absence of trunk disease symptoms. Trunk core samples were taken from the disease-escape vines and neighbouring symptomatic vines. Subsequently, the samples’ total fungal and bacterial communities were identified and compared using culture-independent DNA metabarcoding and culture-dependent approaches. After analysing the metabarcoding and culturing results, microbial taxa that were differentially more abundant in disease-escape grapevines and the ones that correlated negatively with GTD pathogens were identified. The next stage of the study is to design a synthetic community using members of the taxa of interest from the disease-escape grapevines. This SynCom will be introduced into young grapevines and monitored for their ability to suppress the development and severity of GTDs. The research results will provide information on the roles (if any) that the grapevine trunk’s microbiome plays in suppressing GTDs

    On covers of cyclic acts over monoids

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    In (Bull. Lond. Math. Soc. 33:385–390, 2001) Bican, Bashir and Enochs finally solved a long standing conjecture in module theory that all modules over a unitary ring have a flat cover. The only substantial work on covers of acts over monoids seems to be that of Isbell (Semigroup Forum 2:95–118, 1971), Fountain (Proc. Edinb. Math. Soc. (2) 20:87–93, 1976) and Kilp (Semigroup Forum 53:225–229, 1996) who only consider projective covers. To our knowledge the situation for flat covers of acts has not been addressed and this paper is an attempt to initiate such a study. We consider almost exclusively covers of cyclic acts and restrict our attention to strongly flat and condition (P) covers. We give a necessary and sufficient condition for the existence of such covers and for a monoid to have the property that all its cyclic right acts have a strongly flat cover (resp. (P)-cover). We give numerous classes of monoids that satisfy these conditions and we also show that there are monoids that do not satisfy this condition in the strongly flat case. We give a new necessary and sufficient condition for a cyclic act to have a projective cover and provide a new proof of one of Isbell’s classic results concerning projective covers. We show also that condition (P) covers are not unique, unlike the situation for projective covers

    Is Non-Alcoholic Fatty Liver Disease Connected with Cognition?: The Complex Interplay between Liver and Brain

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    The prevalence of non-alcoholic fatty liver disease (NAFLD) and its progressive form, non-alcoholic steatohepatitis (NASH), is increasing in parallel with the rising rates of obesity and type 2 diabetes. Approximately one in four adults are diagnosed with liver steatosis globally. NAFLD is associated with insulin resistance, hypertension, obesity, visceral adiposity, and dyslipidaemia. These risk factors are often accompanied by inflammation and oxidative stress, which also play a role in extrahepatic diseases, including conditions related to the central nervous system, such as mild cognitive impairment and Alzheimer’s disease. The number of people living with dementia is approximately 55 million and is estimated to increase to approximately 2 billion people by 2050. Recent studies have found that NAFLD is associated with poorer cognition. The aim of this review was to summarise the findings of hitherto studies that have linked NAFLD with cognition and dementia, as well as to discuss the potential liver–brain pathways

    Is Non-Alcoholic Fatty Liver Disease Connected with Cognition? The Complex Interplay between Liver and Brain

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    The prevalence of non-alcoholic fatty liver disease (NAFLD) and its progressive form, non-alcoholic steatohepatitis (NASH), is increasing in parallel with the rising rates of obesity and type 2 diabetes. Approximately one in four adults are diagnosed with liver steatosis globally. NAFLD is associated with insulin resistance, hypertension, obesity, visceral adiposity, and dyslipidaemia. These risk factors are often accompanied by inflammation and oxidative stress, which also play a role in extrahepatic diseases, including conditions related to the central nervous system, such as mild cognitive impairment and Alzheimer’s disease. The number of people living with dementia is approximately 55 million and is estimated to increase to approximately 2 billion people by 2050. Recent studies have found that NAFLD is associated with poorer cognition. The aim of this review was to summarise the findings of hitherto studies that have linked NAFLD with cognition and dementia, as well as to discuss the potential liver–brain pathways

    Covers of acts over monoids II

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    In 1981 Edgar Enochs conjectured that every module has a flat cover and finally proved this in 2001. Since then a great deal of effort has been spent on studying different types of covers, for example injective and torsion free covers. In 2008, Mahmoudi and Renshaw initiated the study of flat covers of acts over monoids but their definition of cover was slightly different from that of Enochs. Recently, Bailey and Renshaw produced some preliminary results on the `other' type of cover and it is this work that is extended in this paper. We consider free, divisible, torsion free and injective covers and demonstrate that in some cases the results are quite different from the module case

    A theory on reports of constructive (real) and illusory posttraumatic growth

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    It has been suggested that self-reported posttraumatic growth could sometimes be considered as a way for people to protect themselves from the distress of trauma. In this case, reports of posttraumatic growth could be illusory. We suggest a theory on self-reported constructive (real) posttraumatic growth and illusory posttraumatic growth by using Rogers’s (1959) theory and the work by Vaillant (1995). Through this theoretical framework we attempt to explain when reports of posttraumatic growth are likely to be constructive and real and when such reports are likely to represent aspects of illusions. We will also consider the implications for research practice

    Selected Computing Research Papers Volume 7 June 2018

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    Contents Critical Evaluation of Arabic Sentimental Analysis and Their Accuracy on Microblogs (Maha Al-Sakran) Evaluating Current Research on Psychometric Factors Affecting Teachers in ICT Integration (Daniel Otieno Aoko) A Critical Analysis of Current Measures for Preventing Use of Fraudulent Resources in Cloud Computing (Grant Bulman) An Analytical Assessment of Modern Human Robot Interaction Systems (Dominic Button) Critical Evaluation of Current Power Management Methods Used in Mobile Devices (One Lekula) A Critical Evaluation of Current Face Recognition Systems Research Aimed at Improving Accuracy for Class Attendance (Gladys B. Mogotsi) Usability of E-commerce Website Based on Perceived Homepage Visual Aesthetics (Mercy Ochiel) An Overview Investigation of Reducing the Impact of DDOS Attacks on Cloud Computing within Organisations (Jabed Rahman) Critical Analysis of Online Verification Techniques in Internet Banking Transactions (Fredrick Tshane
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