483 research outputs found

    Split (n + t)-color partitions and 2-color F-partitions

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    Andrews [Generalized Frobenius partitions. Memoirs of the American Math. Soc., 301:1{44, 1984] defined the two classes of generalized F-partitions: F-partitions and k-color F-partitions. For many q-series and Rogers-Ramanujan type identities, the bijections are established between F-partitions and (n + t)-color partitions. Recently (n + t)-color partitions have been extended to split (n+t)-color partitions by Agarwal and Sood [Split (n+t)-color partitions and Gordon-McIntosh eight order mock theta functions. Electron. J. Comb., 21(2):#P2.46, 2014]. The purpose of this paper is to study the k-color F-partitions as a combinatorial tool. The paper includes combinatorial proofs and bijections between split (n + t)-color partitions and 2-color F-partitions for some generalized q-series. Our results further give rise to innate three-way combinatorial identities in conjunction with some Rogers-Ramanujan type identities for some particular cases

    Calcretes in the Thar desert: genesis, chronology and palaeoenvironment

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    The calcretes in the Thar desert occur in a variety of settings, including the piedmonts, sheetwash aggraded plains; and this study adds calcretes in regolith and colluvio-alluvial plains to the group of settings in which calcretes occur in the region. Field logs, morphological details and analytical data such as petrographic, cathodoluminescence and geochemical characteristics are described along with a discussion on their implications. Sand dunes and sandy plains dating to <20 ka have weakly developed calcretes. The better-developed calcrete horizons occur in piedmonts, interdunes or in areas that have sufficient groundwater. Deep sections in the region show phases of calcrete development in aeolian sand aggradation at ~150, ~100, ~60 and 27-14 ka. The extensive sheetwash plains have mature calcretes and date to mid-Pleistocene. Our studies indicate that these calcretes represent a hybrid process, where carbonate enrichment of the originally calcareous host occurred due to periodically raised groundwaters, and its differentiation into nodules occurred under subaerial environment i.e., after recession of groundwater. Deep sections also show a stack of discrete calcretes that developed in individual aggradation episodes with hiatuses as indicated by ESR dating results. Nodules display a multiplicity of carbonate precipi tation events and internal reorganization of calcitic groundmass. The process is accompanied by degradation and transformation of unstable minerals, particularly clays and with a neosynthesis of palygorskite. The ancient calcretes are dated from the beginning of the Quaternary to ~600 ka and show more evolved morphologies marked by brecciation, dissolution, laminar growth on brecciated surfaces, pisolites and several generations of re-cementation. Mica/chlorite schists and such other rocks are particularly vulnerable to replacement by carbonate. In an extreme case, replacement of quartzose sandstone was observed also. The presence of stretches of alluvio-colluvial plains in an area presently devoid of drainage bespeaks of occasional high-energy fluvial regime, under a semi-arid climate. The mid-Pleistocene period saw a shift towards more arid climate and this facilitated sheetwash aggradation. Finally, during the late Pleistocene, aggradation of aeolian sands indicated a progressively drier climate. However, this does not find its reflection in stable isotope data. The amount of carbonate in the form of calcretes is substantial. The present studies indicate that aeolian dust or rainwater are minor contributors to the carbonate budget. A more important source was provided by the pre-existing calcretes in the sheetwash aggraded plains and detrital carbonate in the aeolian sediments. The original source of carbonate in the region, however, remains unresolved and will need further investigations. Electron spin resonance protocols for the dating of calcretes were developed as a part of this study and the results accorded well with geological reasoning

    The utilization of antidepressants and benzodiazepines among people with major depression in Canada

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    Objective: Although clinical guidelines recommend monotherapy with antidepressants (ADs) for major depression, polypharmacy with benzodiazepines (BDZs) remains an issue. Risks associated with such treatments include tolerance and dependence, among others. We assessed the prevalence and determinants of AD and BDZ utilization among Canadians who experienced a major depressive episode (MDE) in the previous 12 months, and determined the association of seeing a psychiatrist on the utilization of ADs and BDZs. Method: Data were drawn from the 2002 Canadian Community Health Survey: Health and Well-Being, a nationally representative sample of Canadians aged 15 years and older. Descriptive statistics quantified utilization, while logistic regression identified factors associated with utilization, such as sociodemographic characteristics or type of physician seen. Sampling weights and bootstrap variance estimations were used for all analysis. Results: The overall prevalence of AD and BDZ utilization was 49.3% of respondents who experienced an MDE in the past 12 months and reported AD use. Key determinants of utilization were younger age and unemployment in the past week (OR 2.6; P < 0.001). Being seen by a psychiatrist increased utilization (OR 2.5; P < 0.001), possibly because psychiatrists were seeing patients with severe depression. Conclusion: A large proportion of people with past-year MDEs utilized ADs and BDZs. It is unclear how much of this is appropriate given that evidence-based clinical guidelines recommend monotherapy with ADs in the treatment of major depression

    Insomnia, Psychiatric Disorders and Suicidal Ideation in a National Representative Sample of Active Canadian Forces Members

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    Background Past research on the association between insomnia and suicidal ideation (SI) has produced mixed findings. The current study explored the relationship between insomnia, SI, and past-year mental health status among a large Canadian Forces (CF) sample. Method Data was obtained from the 2013 Canadian Forces Mental Health Survey (CFMHS), and included a large representative sample of Canadian Regular Forces personnel (N = 6700). A series of univariate logistic regressions were conducted to test individual associations between past-year mental health status, insomnia, and potential confounds and SI. Mental health status included three groups: 0, 1, or two or more probable diagnoses of posttraumatic stress disorder (PTSD), major depressive disorder (MDD), generalized anxiety disorder (GAD), panic disorder (PD) and alcohol abuse/dependence. Stepwise multivariate logistic regression was used to assess the relationship between insomnia and SI with mental health status as a moderator. Results 40.8% of respondents reported experiencing insomnia. Both insomnia and number of mental health conditions incrementally increased the risk of SI. However, past-year mental health status was a significant moderator of this relationship, such that for CF personnel with either no (AOR = 1.61, 1.37–1.89) or only one past-year mental health condition (AOR = 1.39, 1.12–1.73), an incremental increase in insomnia was associated with an increased likelihood of SI. However, in personnel with two or more past-year mental health disorders, insomnia was no longer significantly associated with SI (AOR = 1.04, 0.81–1.33). Conclusions Insomnia significantly increased the odds of SI, but only among individuals with no or one mental health condition. Findings highlight the importance of assessing insomnia among CF members in order to further suicide prevention efforts

    A putative heat-responsive transcription factor (TaHD97) and its targets in wheat (Triticum aestivum) providing thermotolerance

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    214-223Transcription factors (TFs) are protein, which perform their role at transcriptional level by affecting the expression of various genes associated with metabolic pathways, growth and stress-associated genes (SAGs) at different developmental stages. Here, we identified 38 novel heat-responsive transcription factor genes from wheat cv. HD2985 by mining the de novo transcriptome data derived from heat shock (HS) treated wheat. Based on digital gene expression (DGE), a putative transcript (TaHD97) of ~1.1 kbas amplified and cloned from wheat cv. HD2985. The presence of heat stress transcription factor (HSF) DNA binding domain was observed in the amino acid sequence. Differential expression of TaHD97 was observed in HD2985 (thermotolerant) and HD2329 (thermosensitive) under heat stress. Tissue specific expression analysis showed up-regulation of TaHD97 in leaves, stem and endospermic tissues and down-regulation in root under HS. A positive correlation was established between the expression of TaHD97 and its target gene (HSP17 and HSP90) in wheat under heat stress. HSP17 transcripts were observed more in leaves of HD2985, as compared to HD2329. Thermotolerance related biochemical enzymes (SOD, CAT, GPX and TBARS) were observed higher in wheat cv. HD2985 showing maximum expression of TaHD97 under heat stress. There is a need for the functional validation of the gene TaHD97 in order to use it for the regulation of sHSP (catalytic chaperone) - a novel approach towards augmenting thermotolerance in wheat under heat stress

    Impact of participatory silvipastoral intervention and soil conservation measures for forage resource enhancement in western Himalaya

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    Livestock rearing is an important component of rural economy in mid-hills of Himalaya. Inspite of abundant available feed resources, total available biomass is insufficient to sustain the livestock population. Fodder trees particularly in hill ecosystem play an important role in supplementing the fodder requirement especially during the lean period. Information gathered and analysis concludes that Grewia optiva is the most important fodder tree in terms of dominance, palatability and increase in milk yield followed by Artocarpus chaplasha, Morus alba, Bauhinia variegata, Albizia lebbeck and Terminalia alata in Kangra and Mandi districts of Himachal Pradesh. The crude protein content was found highest in Grewia optiva (19.38%) followed by Albizia lebbeck (18.85%), Dendrocalamus hamiltonii (18.01%) and minimum in case of Quercus incana (9.27%). During scarcity of fodder Ficus religiosa is the only fodder tree fed throughout the year. The established silvipasture produced leaf biomass of 2.77 to 6.77 DM kg/tree (Ghanetta), 2.12 to 5.96 DM kg/tree (Jogindernagar) and 2.25 to 6.93 DM kg/tree (Dagoh). Fodder trees planted under silvipastoral system produced average biomass of 1.83 DM tonnes/ha (Ghanetta), 1.49 DM tonnes/ha (Jogindernagar) and 1.66 DM tonnes/ha (Dagoh). Rainfall events of more than 50 mm, though quite less in number (25/165, 24/192 and 17/149), contributed 47.7, 82.3 and 81.7% to the total runoff at Ghanetta, Jogindernagar and Dagoh, respectively. Among the resource conservation measures trenching in combination with vegetative barrier allowed only 8.2% of rain as runoff compared to 41.5% under control (no measure). The silvipasture systems coupled with contour staggered trenches and / or vegetative barrier can effectively arrest the environmental degradation

    Does pre-operative psychological distress affect patient satisfaction after primary total hip arthroplasty?

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    <p>Abstract</p> <p>Background</p> <p>There are concerns that pre-operative psychological distress might be associated with reduced patient satisfaction after total hip replacement (THR).</p> <p>Methods</p> <p>We investigated this in a multi-centre prospective study between January 1999 and January 2002. We dichotomised the patients into the mentally distressed (MHS ≤ 56) and the not mentally distressed (MHS > 56) groups based on their pre-operative Mental Health Score (MHS) of SF36.</p> <p>Results</p> <p>448 patients (340 not distressed and 108 distressed) completed the patient satisfaction survey. Patient satisfaction rate at five year was 96.66% (415/448). There was no difference in patient satisfaction or willingness to have the surgery between the two groups. None of pre-operative variables predicted five year patient satisfaction in logistic regression.</p> <p>Conclusions</p> <p>Patient satisfaction after surgery may not be adversely affected by pre-operative psychological distress.</p

    The course of untreated anxiety and depression, and determinants of poor one-year outcome: a one-year cohort study

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    <p>Abstract</p> <p>Background</p> <p>Little is known about the course and outcome of untreated anxiety and depression in patients with and without a self-perceived need for care. The aim of the present study was to examine the one-year course of untreated anxiety and depression, and to determine predictors of a poor outcome.</p> <p>Method</p> <p>Baseline and one-year follow-up data were used of 594 primary care patients with current anxiety or depressive disorders at baseline (established by the Composite Interview Diagnostic Instrument (CIDI)), from the Netherlands Study of Depression and Anxiety (NESDA). Receipt of and need for care were assessed by the Perceived Need for Care Questionnaire (PNCQ).</p> <p>Results</p> <p>In depression, treated and untreated patients with a perceived treatment need showed more rapid symptom decline but greater symptom severity at follow-up than untreated patients without a self-perceived mental problem or treatment need. A lower education level, lower income, unemployment, loneliness, less social support, perceived need for care, number of somatic disorders, a comorbid anxiety and depressive disorder and symptom severity at baseline predicted a poorer outcome in both anxiety and depression. When all variables were considered at the same time, only baseline symptom severity appeared to predict a poorer outcome in anxiety. In depression, a poorer outcome was also predicted by more loneliness and a comorbid anxiety and depressive disorder.</p> <p>Conclusion</p> <p>In clinical practice, special attention should be paid to exploring the need for care among possible risk groups (e.g. low social economic status, low social support), and support them in making an informed decision on whether or not to seek treatment.</p

    Prediction and prevention of suicide in patients with unipolar depression and anxiety

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    Epidemiological data suggest that between 59 and 87% of suicide victims suffered from major depression while up to 15% of these patients will eventually commit suicide. Male gender, previous suicide attempt(s), comorbid mental disorders, adverse life-situations, acute psycho-social stressors etc. also constitute robust risk factors. Anxiety and minor depression present with a low to moderate increase in suicide risk but anxiety-depression comorbidity increases this risk dramatically Contrary to the traditional psychoanalytic approach which considers suicide as a retrospective murder or an aggression turned in-wards, more recent studies suggest that the motivations to commit suicide may vary and are often too obscure. Neurobiological data suggest that low brain serotonin activity might play a key role along with the tryptophan hydroxylase gene. Social factors include social support networks, religion etc. It is proven that most suicide victims had asked for professional help just before committing suicide, however they were either not diagnosed (particularly males) or the treatment they received was inappropriate or inadequate. The conclusion is that promoting suicide prevention requires the improving of training and skills of both psychiatrists and many non-psychiatrists and especially GPs in recognizing and treating depression and anxiety. A shift of focus of attention is required in primary care to detect potentially suicidal patients presenting with psychological problems. The proper use of antidepressants, after a careful diagnostic evaluation, is important and recent studies suggest that successful acute and long-term antidepressant pharmacotherapy reduces suicide morbidity and mortality

    Strategies of the honeybee Apis mellifera during visual search for vertical targets presented at various heights: a role for spatial attention?

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    When honeybees are presented with a colour discrimination task, they tend to choose swiftly and accurately when objects are presented in the ventral part of their frontal visual field. In contrast, poor performance is observed when objects appear in the dorsal part. Here we investigate if this asymmetry is caused by fixed search patterns or if bees can use alternative search mechanisms such as spatial attention, which allows flexible focusing on different areas of the visual field. We asked individual honeybees to choose an orange rewarded target among blue distractors. Target and distractors were presented in the ventral visual field, the dorsal field or both. Bees presented with targets in the ventral visual field consistently had the highest search efficiency, with rapid decisions, high accuracy and direct flight paths. In contrast, search performance for dorsally located targets was inaccurate and slow at the beginning of the test phase, but bees increased their search performance significantly after a few learning trials: they found the target faster, made fewer errors and flew in a straight line towards the target. However, bees needed thrice as long to improve the search for a dorsally located target when the target's position changed randomly between the ventral and the dorsal visual field. We propose that honeybees form expectations of the location of the target's appearance and adapt their search strategy accordingly. Different possible mechanisms of this behavioural adaptation are discussed.L.M. was recipient of a DOC-fFORTE fellowship of the Austrian Academy of Science at the Department of Integrative Zoology, University of Vienna. L.C. is supported by an ERC Advanced Grant and a Royal Society Wolfson Research Merit Award
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