439 research outputs found

    Beyond rest and quiescence (endodormancy and ecodormancy) : A novel model for quantifying plant-environment interaction in bud dormancy release

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    Bud dormancy of plants has traditionally been explained either by physiological growth arresting conditions in the bud or by unfavourable environmental conditions, such as non-growth-promoting low air temperatures. This conceptual dichotomy has provided the framework also for developing process-based plant phenology models. Here, we propose a novel model that in addition to covering the classical dichotomy as a special case also allows the quantification of an interaction of physiological and environmental factors. According to this plant-environment interaction suggested conceptually decades ago, rather than being unambiguous, the concept of "non-growth-promoting low air temperature" depends on the dormancy status of the plant. We parameterized the model with experimental results of growth onset for seven boreal plant species and found that based on the strength of the interaction, the species can be classified into three dormancy types, only one of which represents the traditional dichotomy. We also tested the model with four species in an independent experiment. Our study suggests that interaction of environmental and physiological factors may be involved in many such phenomena that have until now been considered simply as plant traits without any considerations of effects of the environmental factors.Peer reviewe

    Smoking, Alcohol Intake and Torque Teno Virus in Stable Kidney Transplant Recipients

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    Torque Teno Virus (TTV) is a non-pathogenic virus that is highly prevalent among kidney transplant recipients (KTRs). Its circulating load is associated with an immunological status in KTR and is considered a promising tool for guiding immunosuppression. To allow for optimal guidance, it is important to identify other determinants of TTV load. We aimed to investigate the potential association of smoking and alcohol intake with TTV load. For this cross-sectional study, serum TTV load was measured using PCR in stable kidney transplant recipients at ≥1 year after transplantation, and smoking status and alcohol intake were assessed through questionnaires and measurements of urinary cotinine and ethyl glucuronide. A total of 666 KTRs were included (57% male). A total of 549 KTR (82%) had a detectable TTV load (3.1 ± 1.5 log 10 copies/mL). In KTR with a detectable TTV load, cyclosporin and tacrolimus use were positively associated with TTV load (St. β = 0.46, p &lt; 0.001 and St. β = 0.66, p &lt; 0.001, respectively), independently of adjustment for potential confounders. Current smoking and alcohol intake of &gt;20 g/day were negatively associated with TTV load (St. β = -0.40, p = 0.004 and St. β = -0.33, p = 0.009, respectively), independently of each other and of adjustment for age, sex, kidney function, time since transplantation and calcineurin inhibitor use. This strong association of smoking and alcohol intake with TTV suggests a need to account for the smoking status and alcohol intake when applying TTV guided immunosuppression in KTR. </p

    Smoking, Alcohol Intake and Torque Teno Virus in Stable Kidney Transplant Recipients

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    Torque Teno Virus (TTV) is a non-pathogenic virus that is highly prevalent among kidney transplant recipients (KTRs). Its circulating load is associated with an immunological status in KTR and is considered a promising tool for guiding immunosuppression. To allow for optimal guidance, it is important to identify other determinants of TTV load. We aimed to investigate the potential association of smoking and alcohol intake with TTV load. For this cross-sectional study, serum TTV load was measured using PCR in stable kidney transplant recipients at ≥1 year after transplantation, and smoking status and alcohol intake were assessed through questionnaires and measurements of urinary cotinine and ethyl glucuronide. A total of 666 KTRs were included (57% male). A total of 549 KTR (82%) had a detectable TTV load (3.1 ± 1.5 log 10 copies/mL). In KTR with a detectable TTV load, cyclosporin and tacrolimus use were positively associated with TTV load (St. β = 0.46, p &lt; 0.001 and St. β = 0.66, p &lt; 0.001, respectively), independently of adjustment for potential confounders. Current smoking and alcohol intake of &gt;20 g/day were negatively associated with TTV load (St. β = -0.40, p = 0.004 and St. β = -0.33, p = 0.009, respectively), independently of each other and of adjustment for age, sex, kidney function, time since transplantation and calcineurin inhibitor use. This strong association of smoking and alcohol intake with TTV suggests a need to account for the smoking status and alcohol intake when applying TTV guided immunosuppression in KTR. </p

    Smoking, Alcohol Intake and Torque Teno Virus in Stable Kidney Transplant Recipients

    Get PDF
    Torque Teno Virus (TTV) is a non-pathogenic virus that is highly prevalent among kidney transplant recipients (KTRs). Its circulating load is associated with an immunological status in KTR and is considered a promising tool for guiding immunosuppression. To allow for optimal guidance, it is important to identify other determinants of TTV load. We aimed to investigate the potential association of smoking and alcohol intake with TTV load. For this cross-sectional study, serum TTV load was measured using PCR in stable kidney transplant recipients at ≥1 year after transplantation, and smoking status and alcohol intake were assessed through questionnaires and measurements of urinary cotinine and ethyl glucuronide. A total of 666 KTRs were included (57% male). A total of 549 KTR (82%) had a detectable TTV load (3.1 ± 1.5 log 10 copies/mL). In KTR with a detectable TTV load, cyclosporin and tacrolimus use were positively associated with TTV load (St. β = 0.46, p &lt; 0.001 and St. β = 0.66, p &lt; 0.001, respectively), independently of adjustment for potential confounders. Current smoking and alcohol intake of &gt;20 g/day were negatively associated with TTV load (St. β = -0.40, p = 0.004 and St. β = -0.33, p = 0.009, respectively), independently of each other and of adjustment for age, sex, kidney function, time since transplantation and calcineurin inhibitor use. This strong association of smoking and alcohol intake with TTV suggests a need to account for the smoking status and alcohol intake when applying TTV guided immunosuppression in KTR. </p

    Smoking, Alcohol Intake and Torque Teno Virus in Stable Kidney Transplant Recipients

    Get PDF
    Torque Teno Virus (TTV) is a non-pathogenic virus that is highly prevalent among kidney transplant recipients (KTRs). Its circulating load is associated with an immunological status in KTR and is considered a promising tool for guiding immunosuppression. To allow for optimal guidance, it is important to identify other determinants of TTV load. We aimed to investigate the potential association of smoking and alcohol intake with TTV load. For this cross-sectional study, serum TTV load was measured using PCR in stable kidney transplant recipients at ≥1 year after transplantation, and smoking status and alcohol intake were assessed through questionnaires and measurements of urinary cotinine and ethyl glucuronide. A total of 666 KTRs were included (57% male). A total of 549 KTR (82%) had a detectable TTV load (3.1 ± 1.5 log 10 copies/mL). In KTR with a detectable TTV load, cyclosporin and tacrolimus use were positively associated with TTV load (St. β = 0.46, p &lt; 0.001 and St. β = 0.66, p &lt; 0.001, respectively), independently of adjustment for potential confounders. Current smoking and alcohol intake of &gt;20 g/day were negatively associated with TTV load (St. β = -0.40, p = 0.004 and St. β = -0.33, p = 0.009, respectively), independently of each other and of adjustment for age, sex, kidney function, time since transplantation and calcineurin inhibitor use. This strong association of smoking and alcohol intake with TTV suggests a need to account for the smoking status and alcohol intake when applying TTV guided immunosuppression in KTR. </p

    Creatine and creatinine quantified using nuclear magnetic resonance:A method validation study and clinical associations between circulating creatine and fatigue in kidney transplant recipients

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    Background: A potential contributor to fatigue in kidney transplant recipients (KTR) may be impaired creatine homeostasis. We developed and validated a high-throughput NMR assay allowing for simultaneous measurement of circulating creatine and creatinine, and determined plasma creatine and estimated intramuscular creatine concentrations in KTRs, delineated their determinants and explored their associations with self-reported fatigue.Methods: An NMR assay was developed and validated for measurement of circulating creatinine and creatine concentrations. Plasma creatine and creatinine concentrations were measured in 618 KTR. Fatigue was assessed using the checklist individual strength. Associations of creatine parameters with fatigue was assessed using linear mixed effect models.Results: The NMR-based assay had good sensitivity, precision and demonstrated linearity across a large range of values. Among KTR, the mean age was 56 ± 13 years, 62% were men and eGFR was 54 ± 18 ml/min/1.73 m2. Plasma creatine concentration was 27 [19–39] µmol/L. Estimated intramuscular creatine concentration was 27 ± 7 mmol/kg. Higher plasma creatine concentration and higher estimated intramuscular creatine concentration were independently associated with a lower total fatigue score and less motivation problems.Conclusion: An NMR method for measurement of circulating creatine and creatinine which offers the potential for accurate and efficient quantification was developed. The found associations suggest that improving creatine status may play a beneficial role in mitigating fatigue.</p

    The Design of the n2EDM Experiment

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    We present the design of a next-generation experiment, n2EDM, currently under construction at the ultracold neutron source at the Paul Scherrer Institute (PSI) with the aim of carrying out a high-precision search for an electric dipole moment of the neutron. The project builds on experience gained with the previous apparatus operated at PSI until 2017, and is expected to deliver an order of magnitude better sensitivity with provision for further substantial improvements. An overview is of the experimental method and setup is given, the sensitivity requirements for the apparatus are derived, and its technical design is described

    Barriers to home care for terminally ill Turkish and Moroccan migrants, perceived by GPs and nurses: a survey

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    BACKGROUND: Previous qualitative research proved that relatives of elderly terminally ill Turkish and Moroccan immigrants experience several barriers to the use of Dutch professional home care. The aim of this study was to explore how general practitioners and home care nurses perceive the home care for terminally ill Turkish and Moroccan migrants and their families in the Netherlands. METHODS: Questionnaires were sent to home care organizations and GPs working in areas where most of these migrants are living. 93 nurses and 78 GPs provided information about their experiences and opinions regarding home care for this group of patients. The data were analyzed by descriptive statistics. RESULTS: GPs refer relatively few patients from these migrant groups to home care. They often find it difficult to assess the needs of these patients and their families. In 40% of the GPs' cases in which terminally ill Turkish and Moroccan migrants were not referred to home care, the GP regretted this afterwards: the patients had not received sufficient qualified care, and their informal carers had often become overburdened. In addition, home care nurses often express dissatisfaction with the home care given to terminally ill Turkish or Moroccan patients, because of communication problems, the patients' lack of knowledge of the disease, or difficulties in making suitable appointments with the patient or with the family. CONCLUSIONS: Nurses and GPs cite chiefly similar factors influencing access to and use of home care as family members did in a previous study. However, according to GPs and nurses, the main barrier to the use of home care concerns communication problems, while relatives cited the preference for family care as the main reason for abstaining from the use of home care. (aut. ref.
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