82 research outputs found

    Foraging Behavior of Swainson\u27s Thrushes (Catharus ustulatus) During Spring Migration through Arkansas

    Get PDF
    Foraging behavior of Swainson’s Thrushes on spring migration was studied in western Arkansas in the spring of 2013 and 2014. Observations were made in two forested field sites, one of them urban and the other suburban. The former had a significantly higher woody stem area (cm2) than the latter. For each foraging observation, the following three parameters were noted: Foraging Stratum (Ground, Shrub, Sapling, Sub canopy, and Canopy); Foraging Substrate (Ground/Litter, Herb, Foliage, Bark, and Air); and Foraging Maneuver (Glean, Probe, Dive/Glean, Hover, Jump Hover, and Hawking). We tested the hypotheses that these foraging variables differed significantly between the urban and suburban sites, and between the two years. These hypotheses were rejected for all three parameters. The consolidated data from both the sites and years revealed that a significantly higher proportion (67%) of the observations were on the Ground stratum, compared to the Shrub (13.7%) and Sapling strata (13%). Similarly, a significantly higher proportion (66%) of the foraging substrate used was Ground/Litter, followed by Foliage (16.7%) and Bark (15.8%). Gleaning was the most common foraging maneuver used (71.5%), and was significantly higher than Probing (12.3%) and Dive Gleaning (8.4%)

    Small Mammal Abundances in a Grassland and Forest Area at the Lake Fayetteville Environmental Center, Arkansas

    Get PDF
    We examined changes in abundance of small mammals in forest and prairie-grassland habitat at Lake Fayetteville, Arkansas over a period of 32 years. We estimated the population size of small mammals using a mark-recapture method by capturing small mammals employing rat-sized Sherman live traps laid out in a grid with 8 rows of traps, 15 traps per row, 9.14 m (30 feet) between traps and rows covering an area of 1.01 ha (2.5 acres) in size. Six species of mammals were trapped in the prairie-grassland and three species were captured in the forest habitat. In the forest, the white-footed deermouse (Peromuscus leucopus)was greatest in 1998 and in 2006. In the prairie-grassland, the population of hispid cotton rats (Sigmodon hispidus) were greatest in 2004, 2008, 2010 and 2014 and have increased over the years with the change in grass composition. The prairie-grassland in 1962 was mainly a broomsedge bluestem (Andropogon virginicus) field but as time progressed more and more prairie grasses invaded helped by controlled burns and removal of the invading eastern red cedars (Juniperus virginiana). The population of Sigmodon hispidus was weakly correlated with the minimum winter temperatures from the previous year

    Imaging algorithm for COVID-19: A practical approach

    Get PDF
    © 2020 Elsevier Inc. The global pandemic of COVID-19 pneumonia caused by the novel coronavirus (SARS-CoV-2) has strained healthcare resources across the world with emerging challenges of mass testing, resource allocation and management. While reverse transcriptase-polymerase chain reaction (RT-PCR) test is the most commonly utilized test and considered the current gold standard for diagnosis, the role of chest imaging has been highlighted by several studies demonstrating high sensitivity of computed tomography (CT). Many have suggested using CT chest as a first-line screening tool for the diagnosis of COVID-19. However, with advancement of laboratory testing and challenges in obtaining a CT scan without significant risk to healthcare providers, the role of imaging in diagnosis has been questioned. Several imaging societies have released consensus statements and guidelines on utilizing imaging resources and optimal reporting. In this review, we highlight the current evidence on various modalities in thoracic imaging for the diagnosis of COVID-19 and describe an algorithm on how to use these resources in an optimal fashion in accordance with the guidelines and statements released by major imaging societies

    Foraging habitat selection of shrubland bird community in tropical dry forest

    Get PDF
    Habitat loss due to increasing anthropogenic disturbance is the major driver for bird population declines across the globe. Within the Eastern Ghats of India, shrubland bird communities are threatened by shrinking of suitable habitats due to increased anthropogenic disturbance and climate change. The development of an effective habitat management strategy is hampered by the absence of data for this bird community. To address this knowledge gap, we examined foraging sites for 14 shrubland bird species, including three declining species, in three study areas representing the shrubland type of forest community in the Eastern Ghats. We recorded microhabitat features within an 11 m radius of observed foraging points and compared these data with similar data from random plots. We used chi-square to test the association between plant species and bird species for sites where they were observed foraging. We observed significant differences between foraging sites of all the study species and random plots, thus indicating selection for foraging habitat. Using linear discriminant analysis, we found that the microhabitat features important for the bird species were shrub density, vegetational height, vertical foliage stratification, grass height, and percent rock cover. Our results show that diet guild and foraging strata influence the foraging microhabitat selection of a species (e.g., ground-foraging species differed significantly from other species). Except for two species, all focal birds were associated with at least one plant species. The plant-bird association was based on foraging, structural, or behavioral preferences. Several key factors affecting foraging habitat such as shrub density can be actively managed at the local scale. Strategic and selective harvesting of forest products and a spatially and temporally controlled livestock grazing regime may allow regeneration of scrubland and create conditions favorable to birds

    Monoamine oxidase-dependent endoplasmic reticulum-mitochondria dysfunction and mast cell degranulation lead to adverse cardiac remodeling in diabetes.

    Get PDF
    Monoamine oxidase (MAO) inhibitors ameliorate contractile function in diabetic animals, but the mechanisms remain unknown. Equally elusive is the interplay between the cardiomyocyte alterations induced by hyperglycemia and the accompanying inflammation. Here we show that exposure of primary cardiomyocytes to high glucose and pro-inflammatory stimuli leads to MAO-dependent increase in reactive oxygen species that causes permeability transition pore opening and mitochondrial dysfunction. These events occur upstream of endoplasmic reticulum (ER) stress and are abolished by the MAO inhibitor pargyline, highlighting the role of these flavoenzymes in the ER/mitochondria cross-talk. In vivo, streptozotocin administration to mice induced oxidative changes and ER stress in the heart, events that were abolished by pargyline. Moreover, MAO inhibition prevented both mast cell degranulation and altered collagen deposition, thereby normalizing diastolic function. Taken together, these results elucidate the mechanisms underlying MAO-induced damage in diabetic cardiomyopathy and provide novel evidence for the role of MAOs in inflammation and inter-organelle communication. MAO inhibitors may be considered as a therapeutic option for diabetic complications as well as for other disorders in which mast cell degranulation is a dominant phenomenon

    Bacteria-inducing legume nodules involved in the improvement of plant growth, health and nutrition

    Get PDF
    Bacteria-inducing legume nodules are known as rhizobia and belong to the class Alphaproteobacteria and Betaproteobacteria. They promote the growth and nutrition of their respective legume hosts through atmospheric nitrogen fixation which takes place in the nodules induced in their roots or stems. In addition, rhizobia have other plant growth-promoting mechanisms, mainly solubilization of phosphate and production of indoleacetic acid, ACC deaminase and siderophores. Some of these mechanisms have been reported for strains of rhizobia which are also able to promote the growth of several nonlegumes, such as cereals, oilseeds and vegetables. Less studied are the mechanisms that have the rhizobia to promote the plant health; however, these bacteria are able to exert biocontrol of some phytopathogens and to induce the plant resistance. In this chapter, we revised the available data about the ability of the legume nodule-inducing bacteria for improving the plant growth, health and nutrition of both legumes and nonlegumes. These data showed that rhizobia meet all the requirements of sustainable agriculture to be used as bio-inoculants allowing the total or partial replacement of chemicals used for fertilization or protection of crops

    Practical guidelines for rigor and reproducibility in preclinical and clinical studies on cardioprotection

    Get PDF
    The potential for ischemic preconditioning to reduce infarct size was first recognized more than 30 years ago. Despite extension of the concept to ischemic postconditioning and remote ischemic conditioning and literally thousands of experimental studies in various species and models which identified a multitude of signaling steps, so far there is only a single and very recent study, which has unequivocally translated cardioprotection to improved clinical outcome as the primary endpoint in patients. Many potential reasons for this disappointing lack of clinical translation of cardioprotection have been proposed, including lack of rigor and reproducibility in preclinical studies, and poor design and conduct of clinical trials. There is, however, universal agreement that robust preclinical data are a mandatory prerequisite to initiate a meaningful clinical trial. In this context, it is disconcerting that the CAESAR consortium (Consortium for preclinicAl assESsment of cARdioprotective therapies) in a highly standardized multi-center approach of preclinical studies identified only ischemic preconditioning, but not nitrite or sildenafil, when given as adjunct to reperfusion, to reduce infarct size. However, ischemic preconditioning—due to its very nature—can only be used in elective interventions, and not in acute myocardial infarction. Therefore, better strategies to identify robust and reproducible strategies of cardioprotection, which can subsequently be tested in clinical trials must be developed. We refer to the recent guidelines for experimental models of myocardial ischemia and infarction, and aim to provide now practical guidelines to ensure rigor and reproducibility in preclinical and clinical studies on cardioprotection. In line with the above guideline, we define rigor as standardized state-of-the-art design, conduct and reporting of a study, which is then a prerequisite for reproducibility, i.e. replication of results by another laboratory when performing exactly the same experiment

    Plant growth promoting rhizobia: challenges and opportunities

    Get PDF

    Effect of organic amendments on termite infestation in chickpea

    No full text
    The field experiment was conducted at the Research farm, Agriculture Research Station, Swami Keshwanand Rajasthan Agricultural University, Bikaner, during Rabi season in randomized block design with nine treatments, including the control. Out of the seven organic amendments, tested against termites in chickpea, the application of neem cake recorded the lowest 9.97 per cent termite damaged plants, followed by vermicompost (10.43). The highest termite damaged plants (19.53) were observed in plots treated with FYM followed by groundnut cake treated plots (19.47). The maximum grain yield (1325 kg ha-1) was obtained from the plots treated with neem cake, followed by vermicompost (1205 kg ha-1). The minimum yield (1060 kg ha-1) was obtained from the plots treated with FYM. The maximum profit (Rs 8790 ha-1) was obtained from the treatment of vermicompost, followed by poultry manures (Rs 7010 ha-1). The highest incremental cost-benefit ratio (ICBR) of 0.96 was obtained from vermicompost followed by poultry manures (0.69)
    corecore