68 research outputs found

    Seedling mortality in two vulnerable tree species in the sacred groves of Western Ghats, South India

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    Sacred groves form a significant component of the traditional conservation movement in many parts of the tropical world1. The Western Ghats, one of the two mega-diversity centers in India, is dotted with sacred groves, with the highest concentrations located in the central Western Ghats2. Sacred groves are believed to serve as the last refugia for a number of taxa, particularly for rare, endangered and threatened species3,4. Of late due to encroachments and land-use changes, the sacred groves have been increasingly threatened and fragmented 4. During the last century alone,the total area under the groves in Kodagu district in the central Western Ghats decreased by 42%. Besides, more than 46% of the sacred groves in the district are less than 0.4 ha in area. The increased fragmentation of the groves could undermine the utility of these groves in serving as a refugium for the rare, endangered and threatened (RET) species. Here we examine the effects of grove area on the seedling mortality of two economically important and vulnerable tree species

    A comprehensive review on bonding between monolithic ceramics and tooth structure with different adhesive agents.

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    Reliable bonding between the prepared tooth and monolithic ceramics can be achieved by various luting agents available on the market. The selection of luting agent and cementation technique plays an important role in the success of the restoration. With the advent of resin-based adhesive systems as luting agents, clinicians\u27 perspectives have changed to a more conservative approach. Recent systems, chemically adhere the crowns to the prepared tooth structure showing higher bond strength. To reach the aesthetic demands of the patients, all-ceramic restorations were considered over metal-ceramic crowns. Few all-ceramic crowns are brittle, the strength is dependent on the chemical structure and method of fabrication. While some all-ceramic restorations gain strength after cementation. Thus, the choice of luting agent used in cementing all-ceramic crowns is crucial. Even though many luting agents are being introduced no single luting agent fulfilled all the requirements. Among them, adhesive cements showed greater bond strength and enhanced the retention of minimal preparation, which are less retentive. Traditional non-adhesive agents can be used in retentive preparations that bond through mechanical means rather than the chemical bond seen in newer adhesive cements. Also, surface treatments of zirconia showed greater bond strengths irrespective of the luting agent being used. These include air abrasion, acid etching, applying silane couplers, and primers that increase the surface area for adhesion. The use of all-ceramic restorations, the need for surface treatments, types of surface treatments, adhesion and adhesive agents, and evidence from current in vitro research on monolithic ceramics and tooth adhesion were all discussed in this review

    Micro-machining techniques for the fabrication of fibre Fabry-Perot sensors

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    Fabry-Perot optical fibre sensors have been used extensively for measuring a variety of parameters such as strain, temperature, pressure and vibration. Conventional extrinsic fibre Fabry-Perot sensors are associated with problems such as calibration of the gauge length of each individual sensor, their relatively large size compared to the diameter of optical fibre and a manual manufacturing method that leads to poor reproducibility. Therefore, new designs and fabrication techniques for producing fibre Fabry-Perot sensors are required to address the problems of extrinsic fibre Fabry-Perot sensors. This thesis investigates hydrofluoric acid etching and F2-laser micro-machining of optical fibres to produce intrinsic Fabry-Perot cavities. Chemical etching of single mode fused silica fibres produced cavities across the core of the fibres due to preferential etching of the doped-region. Scanning electron microscope, interferometric surface profiler and CCD spectrometer studies showed that the optical quality of the etched cavities was adequate to produce Fabry-Perot interference. Controlled fusion splicing of etched fibres produced intrinsic Fabry-Perot cavities. These sensors were surface-mounted on composite coupons and their response to applied strain was studied using low coherence interferometry. These sensors showed linear and repeatable response with the strain measured by the electrical resistance strain gauges. To carry out F2-laser micro-machining of fused silica and sapphire substrates, a micro-machining station was designed and constructed. This involved the design of illumination optics for 157 nm laser beam delivery, the design and construction of beam delivery chamber, target alignment and monitoring systems. Ablation of fused silica and sapphire disks was carried out to determine ablation parameters suitable for micro-machining high aspect ratio microstructures that have adequate optical quality to produce Fabry-Perot interference. Cavities were micro-machined through the diameter of SMF 28 and SM 800 fibres at different energy densities. CCD interrogation of these intrinsic fibre cavities ablated at an energy density of 25 x 10 4 Jm -2 produced Fabry-Perot interference fringes. The feasibility of micro-machining high aspect ratio cavities at the cleaved end-face of the fused silica fibres and through the diameter of sapphire fibres was demonstrated. A technique based on in-situ laser-induced fluorescence monitoring was developed to determine the alignment of optical fibres and ablation depth during ablation through the fibre diameter. Ablation of cavities through the diameter of fibre Bragg gratings showed that the heat-generated inside the cavity during ablation had no effect on the peak reflection and the integrity of core and cladding of the fibre. Finally, a pH-sensor, a chemical sensor based on multiple cavities ablated in multimode fibres and a feasible design for pressure sensor fabrication based on ablated cavity in a single mode fibre were demonstrated.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Credible practice of modeling and simulation in healthcare: ten rules from a multidisciplinary perspective

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    The complexities of modern biomedicine are rapidly increasing. Thus, modeling and simulation have become increasingly important as a strategy to understand and predict the trajectory of pathophysiology, disease genesis, and disease spread in support of clinical and policy decisions. In such cases, inappropriate or ill-placed trust in the model and simulation outcomes may result in negative outcomes, and hence illustrate the need to formalize the execution and communication of modeling and simulation practices. Although verification and validation have been generally accepted as significant components of a model\u27s credibility, they cannot be assumed to equate to a holistic credible practice, which includes activities that can impact comprehension and in-depth examination inherent in the development and reuse of the models. For the past several years, the Committee on Credible Practice of Modeling and Simulation in Healthcare, an interdisciplinary group seeded from a U.S. interagency initiative, has worked to codify best practices. Here, we provide Ten Rules for credible practice of modeling and simulation in healthcare developed from a comparative analysis by the Committee\u27s multidisciplinary membership, followed by a large stakeholder community survey. These rules establish a unified conceptual framework for modeling and simulation design, implementation, evaluation, dissemination and usage across the modeling and simulation life-cycle. While biomedical science and clinical care domains have somewhat different requirements and expectations for credible practice, our study converged on rules that would be useful across a broad swath of model types. In brief, the rules are: (1) Define context clearly. (2) Use contextually appropriate data. (3) Evaluate within context. (4) List limitations explicitly. (5) Use version control. (6) Document appropriately. (7) Disseminate broadly. (8) Get independent reviews. (9) Test competing implementations. (10) Conform to standards. Although some of these are common sense guidelines, we have found that many are often missed or misconstrued, even by seasoned practitioners. Computational models are already widely used in basic science to generate new biomedical knowledge. As they penetrate clinical care and healthcare policy, contributing to personalized and precision medicine, clinical safety will require established guidelines for the credible practice of modeling and simulation in healthcare

    Effect of sub-optimal moisture levels on the quality of groundnut (Arachis hypogaea L.) during storage in triple-layer hermetic storage bags

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    Storage is an important aspect of groundnut, as the in-shell and shelled kernels are prone to infestation by insects, pests, and fungi. Among several storage pests, the groundnut bruchid, Caryedon serratus, causes serious losses. Farmers often resort to different management practices, including hermetic storage, to control it. The moisture content of the commodity plays an important role in insect infestation during storage. Drying to safe moisture levels before storage is known to prevent the activity of various living organisms, such as storage pests. However, drying to low levels of moisture may not be economical for farmers, as they may not have access to devices to accurately check product moisture. In this regard, we wanted to demonstrate the efficacy of triple-layer hermetic storage bags in preventing the damage caused by C. serratus when the groundnuts are stored at intermediate (10%) and high (14%) levels of moisture compared to traditionally used bags such as polypropylene bags and jute bags. Groundnut pods at 10% moisture content and 14% moisture content were separately inoculated with adult bruchids and a toxigenic strain of Aspergillus flavus fungal inoculum before storing them for 6 months. Results from groundnut samples taken at two-month intervals indicated that groundnut pods stored in triple-layer hermetic bags were completely free from infestation by C. serratus by recording a zero number of eggs laid, number of pupae, adult emergence, percentage of loss, and percentage of damage up to 6 months of storage, by creating low oxygen (hypoxia) and high carbon dioxide (hypercarbia) conditions. Results also indicate no loss of pod weight stored in triple-layer bags, but a slight reduction in germination percentage was recorded due to a slight increase in fungal activity, but the reduction was significantly less in triple-layer plastic bags compared to other bag types. Similarly, biochemical constituents such as oil and protein content were slightly reduced in triple-layer plastic bags when pods were stored at a 10% moisture level, but a higher reduction was observed at a 14% moisture level. However, the reduction was very high and significant in other bag types at both 10 and 14% moisture levels

    Big Domains Are Novel Ca2+-Binding Modules: Evidences from Big Domains of Leptospira Immunoglobulin-Like (Lig) Proteins

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    binds to a Big domains, which would provide a novel functional role of the proteins containing Big fold. with dissociation constants of 2–4 µM. Lig A9 and Lig A10 domains fold well with moderate thermal stability, have β-sheet conformation and form homodimers. Fluorescence spectra of Big domains show a specific doublet (at 317 and 330 nm), probably due to Trp interaction with a Phe residue. Equilibrium unfolding of selected Big domains is similar and follows a two-state model, suggesting the similarity in their fold. binding

    Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

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    Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

    Modelling human choices: MADeM and decision‑making

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    Research supported by FAPESP 2015/50122-0 and DFG-GRTK 1740/2. RP and AR are also part of the Research, Innovation and Dissemination Center for Neuromathematics FAPESP grant (2013/07699-0). RP is supported by a FAPESP scholarship (2013/25667-8). ACR is partially supported by a CNPq fellowship (grant 306251/2014-0)
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