216 research outputs found

    Climate and Plant Growth in Certain Vegetative Associations

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    The relation of climate to the growth and development of vegetation is of profound importance in both practical and experimental agriculture. It is extremely useful to know the cause of successful growth and establishment, or of partial success or failure, of various species in different plant associations and under widely contrasted climatic conditions. The climatic requirements of various plant types are largely responsible for the results obtained in the case of experimental seedings and plantings of most species. Once the adverse climatic factors are definitely known, failures with plants may be largely avoided by the judicious selection of sites or of species especially adapted to withstand the limiting factors. Therefore, a series of experiments was undertaken, (a) to obtain a comparison of the climatic requirements of the main plant types, and (b) to determine, quantitatively, the relation between various environmental factors on the one hand and plant growth and certain other physiological functions on the other. The results obtained appear to be conclusive in most instances and should prove of value both in experimental and in practical agriculture and forestry

    Grazing Periods and Forage Production on the National Forests

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    Stockmen in the West have always had confidence in the adequacy of the native forage crop to provide pasturage for their livestock. Indeed, under normal climatic conditions this enormous natural resource has not failed the grazier, except where it has been called upon to meet unreasonable demands. The productivity of the range has declined sharply, however, wherever the requirements of plant growth have been disregarded for many years in succession. Where there has been too early or too frequent and to heavy grazing, undue trampling, or some other unsatisfactory feature of range use, the results have been uniformly bad. Many conspicuous examples show that abundant nutritious forage can not be expected in the absence of rational grazing and livestock management

    Impact of Gravel Dredging Operations on Surface Water Quality in Streams in the Upper Cumberland Basin

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    This is a report to the USEPA, Kentucky Division of Water and the Kentucky Water Resources Research Institute, focused on the biologic and morphological impacts of gravel mining in the upper Cumberland basin

    Increased Incidence of Lymphosarcoma in Long-Term Murine Survivors of Lethal Radiation: A Classification of Subtypes

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    poster abstractResidual bone marrow damage (RBMD) persists for years following exposure to radiation and is thought to be due to decreased self-renewal of hematopoietic stem cells (HSC). We previously examined RBMD in murine survivors of lethal radiation modeling a terrorist event [800cGy total-body irradiation (TBI)]. We reported severely deficient HSC potential up to 20mo post-TBI compared to non-TBI age-matched controls, evidenced by minimal engraftment skewed to myeloid cells. CBC and BM cellularity were decreased in TBI mice, most dramatically in old age (>16mo). The percentage of some hematopoietic progenitors was consistently increased in TBI mice (~1.4x higher than non-TBI) possibly due to an increased cell cycling rate compared to non-TBI cells. Of interest, we now report the occurrence of a thymic mass developing in 13-24% of TBI mice 2-19 months post-TBI, compared to <1% of non-TBI. We characterized the Lymphosarcoma into the following groups based on the St. Jude pathology subclassification: Diffuse Lymphosarcoma involving multiple organs, Thymic lymphoma (usually associated with thymic and around the heart), Lymphosarcoma (potentially starting in the spleen and peri-pancreatic lymph nodes (Ab=abdomen)), and follicular lymphoma seen as a diffuse proliferation of lymphocytes in the white pulp area in the spleen. Thymic lymphomas were the most common, followed by Lymphosarcoma (Ab), follicular lymphoma (restricted to white pulp area in the spleen) and diffuse Lymphosarcoma. Immunostain markers revealed the thymic lymphomas were from T-cell lineage and the abdominal Lymphosarcoma were mainly from B-cell lineage. A few mice had disease involving the bone marrow. Taken together, these data suggest that the increased cycling among primitive hematopoietic cells in survivors of lethal radiation may contribute to stem cell exhaustion and subsequent RBMD, as well as predispose survivors to hematopoietic neoplasias

    Pretreatment serum xanthophyll concentrations as predictors of head and neck cancer recurrence and survival

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    BackgroundThe purpose of this study was to examine associations of pretreatment serum carotenoids, tocopherols, and quercetin with prognosis in 154 patients newly diagnosed with head and neck cancer.MethodsPretreatment blood and health surveys were collected. Serum micronutrients were measured by high performance liquid chromatography. Data on recurrence and death were collected annually. Cox proportional hazards models measured associations of serum nutrient concentrations with recurrence and overall survival.ResultsDuring a median follow‐up time of 37 months, there were 32 recurrences and 27 deaths. After controlling for covariates, subjects with high versus low serum xanthophyll and total carotenoid concentrations had significantly longer recurrence‐free time (p = .002 and p = .02, respectively). Overall survival time was significantly longer in patients with high versus low serum xanthophyll concentrations (p = .02).ConclusionFuture research should evaluate the possible benefits of interventions to increase intakes of rich food sources of xanthophylls in this patient population. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1591–E1597, 2016Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137428/1/hed24283.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137428/2/hed24283_am.pd

    Unique Cardiac Purkinje Fiber Transient-Outward Current Beta-Subunit Composition: A Potential Molecular Link to Idiopathic Ventricular Fibrillation.

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    Rationale: A chromosomal-haplotype producing cardiac overexpression of dipeptidyl peptidase-like protein-6 (DPP6) causes familial idiopathic ventricular fibrillation (IVF). The molecular basis of transient-outward current (Ito) in Purkinje fibers (PFs) is poorly understood. We hypothesized that DPP6 contributes to PF Ito and that its overexpression might specifically alter PF Ito-properties and repolarization. Objective: To assess the potential role of DPP6 in PF-Ito. Methods and Results: Clinical data in 5 IVF-patients suggested arrhythmia-origin in the PF conducting-system. PF and ventricular-muscle (VM) Ito had similar density, but PF Ito differed from VM in having tetraethylammonium-sensitivity and slower recovery. DPP6-overexpression significantly increased, whereas DPP6-kockdown reduced, Ito-density and tetraethylammonium-sensitivity in canine PF, but not VM-cells. The K+-channel interacting beta-subunit KChIP2, essential for normal expression of transient outward current (Ito) in VM, was weakly-expressed in human PFs, whereas DPP6 and frequenin (NCS-1) were enriched. Heterologous expression of Kv4.3 in Chinese hamster ovary (CHO)-cells produced very small Ito; Ito-amplitude was greatly enhanced by co-expression with KChIP2 or DPP6. Co expression of DPP6 with Kv4.3 and KChIP2 failed to alter Ito versus Kv4.3/KChIP2 alone, but DPP6 expression with Kv4.3 and NCS-1 (to mimic PF Ito-composition), greatly enhanced Ito versus Kv4.3/NCS-1 and recapitulated characteristic PF kinetic/pharmacological properties. A mathematical model of cardiac PF action potentials showed that Ito-enhancement can greatly accelerate PF repolarization. Conclusions: These results point to a previously-unknown central role of DPP6 in PF Ito, with DPP6 gain-of-function selectively enhancing PF-current, and suggest that a DPP6-mediated PF early repolarization syndrome might be a novel molecular paradigm for some forms of IVF

    A Proposal From The Montpellier World Health Organization Collaborating Centre For Better Management And Prevention Of Anaphylaxis

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    International audienceSince the first description of anaphylaxis in 1902, its clinical importance as an emergency condition has been recognized worldwide. Anaphylaxis is a severe, potentially life-threatening systemic hypersensitivity reaction characterized by rapid onset and the potential to endanger life through respiratory or circulatory compromise. It is usually, although not always, associated with skin and mucosal changes. Although the academic/scientific communities have advocated to promote greater awareness and protocols for the management of anaphylaxis based on best evidence, there are few efforts documenting feedback as to the success of these efforts. In this article, we review the key unmet needs related to the diagnosis and management of anaphylaxis, and propose a public health initiative for prevention measures and a timetable action plan that intends to strengthen the collaboration among health professionals and especially primary care physicians dealing with anaphylaxis, which can encourage enhanced quality of care of patients with anaphylaxis. More than calling for a harmonized action for the best management of anaphylaxis to prevent undue morbidity and mortality, the Montpellier World Health Organization Collaborating Centre here proposes an action plan as a baseline for a global initiative against anaphylaxis. We strongly believe that these collaborative efforts are a strong public health and societal priority that is consistent with the overarching goals of providing optimal care of allergic patients and best practices of allergology

    Can Healthcare Assistant Training (CHAT) improve the relational care of older people? A developmental and feasibility study of a complex intervention

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    Background: Older people account for an increasing proportion of those receiving NHS acute care. The quality of healthcare delivered to older people has come under increased scrutiny. Healthcare assistants (HCAs) provide much of the direct care of older people in hospital. Patients’ experience of care tends to be based on the relational aspects of that care including dignity, empathy and emotional support. Objective(s): We aimed to: understand the relational care training needs of HCAs caring for older people; design a relational care training intervention for HCAs; and assess the feasibility of a cluster-randomised controlled trial to test the new intervention against HCA training as usual. Design: (1) Telephone survey of all NHS hospital Trusts in England to assess current HCA training provision; (2) focus groups of older people and carers and (3) semi-structured interviews with HCAs and other care staff to establish training needs and inform intervention development; (4) feasibility cluster-randomised controlled trial. Setting: (1) All acute NHS hospital Trusts in England; (2,3,4) Three acute NHS hospital Trusts in England and the populations they serve. Participants: (1) 113 of 161 (70.2%) Trusts took part in the telephone survey; (2) 29 older people or carer participants of three focus groups; (3) 30 HCA and 24 ‘other staff’ interviewees; (4) 12 wards (four per Trust); 112 HCAs; 92 patients during the pre-randomisation period and 67 patients during the post-randomisation period. Interventions: For the feasibility trial a training intervention (Older People’s Shoes) for HCAs developed as part of the study was compared with HCA training as usual. Main outcome measures: Patient level outcomes were the experience of emotional care and quality of life during their hospital stay as measured by the Patient Evaluation of Emotional Care during Hospitalisation (PEECH) and the European Quality of Life (EQ-5D) questionnaires. HCA outcomes were empathy measured by the Toronto Empathy Questionnaire (TEQ) and attitudes towards older people measured by the Age Group Evaluation and Description (AGED) Inventory. Ward level outcomes were the quality of HCA/patient interaction measured by the Quality of Interaction Scale (QUIS). Results: (1) A third of Trust telephone survey participants reported HCA training content that we considered to be ‘relational care’. Training for HCAs is variable across Trusts and focused on new recruits. The biggest challenge for HCA training is getting HCAs released from ward duties. (2) Older people and carers are aware of the pressures ward staff are under but good relationships with care staff determines whether the experience of hospital is positive. (3) HCAs have training needs related to ‘difficult conversations’ with patients and relatives; they have particular preferences for learning styles that are not always reflected in available training. (4) In the feasibility trial 187 of the 192 planned ward observation sessions were completed; response to HCA questionnaires at baseline, eight and 12 weeks post-randomisation was 64.2%, 46.4% and 35.7% respectively; 57.2% of eligible patients returned completed questionnaires. Limitations: This was an intervention development and feasibility study so no conclusions can be drawn about the effectiveness of the intervention. Conclusions: The intervention had high acceptability among nurse trainers and HCA learners. Viability of a definitive trial is conditional on overcoming specific methodological (patient recruitment processes) and contextual (involvement of wider ward team) challenges. Future work: Methods to ease the burden of questionnaire completion without compromising ethics or methodological rigour need to be explored. Study registration: ISRCTN1038579
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