144 research outputs found

    Simulated Dynamics of Mixed Versus Uniform Grain Size Sediment Pulses in a Gravel-Bedded River

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    Mountain rivers often receive sediment in the form of episodic, discrete pulses from a variety of natural and anthropogenic processes. Once emplaced in the river, the movement of this sediment depends on flow, grain size distribution, and channel and network geometry. Here, we simulate downstream bed elevation changes that result from discrete inputs of sediment (10,000 m3), differing in volume and grain size distribution, under medium and high flow conditions. We specifically focus on comparing bed responses between mixed and uniform grain size sediment pulses. This work builds on a Lagrangian, bed-material sediment transport model and applies it to a 27 km reach of the mainstem Nisqually River, Washington, USA. We compare observed bed elevation change and accumulation rates in a downstream lake to simulation results. Then we investigate the magnitude, timing, and persistence of downstream changes due to the introduction of synthetic sediment pulses by comparing the results against a baseline condition (without pulse). Our findings suggest that bed response is primarily influenced by the sediment-pulse grain size and distribution. Intermediate mixed-size pulses (~50% of the median bed gravel size) are likely to have the largest downstream impact because finer sizes translate quickly and coarser sizes (median bed gravel size and larger) disperse slowly. Furthermore, a mixed-size pulse, with a smaller median grain size than the bed, increases bed mobility more than a uniform-size pulse. This work has important implications for river management, as it allows us to better understand fluvial geomorphic responses to variations in sediment supply

    Unsupervised segmentation of noisy electron microscopy images using salient watersheds and region merging

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    BACKGROUND: Segmenting electron microscopy (EM) images of cellular and subcellular processes in the nervous system is a key step in many bioimaging pipelines involving classification and labeling of ultrastructures. However, fully automated techniques to segment images are often susceptible to noise and heterogeneity in EM images (e.g. different histological preparations, different organisms, different brain regions, etc.). Supervised techniques to address this problem are often helpful but require large sets of training data, which are often difficult to obtain in practice, especially across many conditions. RESULTS: We propose a new, principled unsupervised algorithm to segment EM images using a two-step approach: edge detection via salient watersheds following by robust region merging. We performed experiments to gather EM neuroimages of two organisms (mouse and fruit fly) using different histological preparations and generated manually curated ground-truth segmentations. We compared our algorithm against several state-of-the-art unsupervised segmentation algorithms and found superior performance using two standard measures of under-and over-segmentation error. CONCLUSIONS: Our algorithm is general and may be applicable to other large-scale segmentation problems for bioimages

    The moderating role of transformational leadership on HR practices in M&A integration

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    Scant research exists examining the effect of HRM practices on employee behavior in M&A integration and the role that leaders play within this. This paper develops a conceptual framework that focuses on the moderating role of transformational leadership on the achievement of human integration and organizational identification in M&A integration. We argue that communication, employee involvement, teamwork, and training and development have a positive effect on employee behavior and their identification with the newly formed organization. Moreover, we argue that transformational leadership behaviors will moderate the implementation of HRM practices in M&As, leading to positive employee behavior and employee identification in the new organization. We suggest that further research is necessary to test propositions of the present study in order to achieve finer-grained understanding of the role of transformational leadership on the achievement of human integration and organizational identification in M&A integration

    Increased waterborne blaNDM-1 resistance gene abundances associated with seasonal human pilgrimages to the Upper Ganges River

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    Antibiotic resistance (AR) is often rooted in inappropriate antibiotic use, but poor water quality and inadequate sanitation exacerbate the problem, especially in emerging countries. An example is increasing multi-AR due to mobile carbapenemases, such as NDM-1 protein (coded by blaNDM-1 genes), which can produce extreme drug-resistant phenotypes. In 2010, NDM-1 positive isolates and blaNDM-1 genes were detected in surface waters across Delhi and have since been detected across the urban world. However, little is known about blaNDM-1 levels in more pristine locations, such as the headwaters of the Upper Ganges River. This area is of particular interest because it receives massive numbers of visitors during seasonal pilgrimages in May/June, including visitors from urban India. Here we quantified blaNDM-1 abundances, other AR genes (ARG) and coliform bacteria in sediments and water column samples from seven sites in the Rishikesh-Haridwar region of the Upper Ganges and five sites on the Yamuna River in Delhi to contrast blaNDM-1 levels and water quality conditions between season and region. Water quality in the Yamuna was very poor (e.g., anoxia at all sites), and blaNDM-1 abundances were high across sites in water (5.4 ± 0.4 log(blaNDM-1·mL-1); 95% confidence interval) and sediment (6.3 ± 0.7 log(blaNDM-1·mg-1)) samples from both seasons. In contrast, water column blaNDM-1 abundances were very low across all sites (2.1 ± 0.6 log(blaNDM-1·mL-1)) in February in the Upper Ganges and water quality was good (e.g., near saturation oxygen). However, per capita blaNDM-1 levels were 20 times greater in June in the Ganges water column relative to February and blaNDM-1 levels significantly correlated with fecal coliform levels (r=0.61; p=0.007). Given waste management infrastructure is limited in Rishikesh-Haridwar; data imply blaNDM-1 levels are higher in visitor's wastes than local residents, which results in seasonally higher blaNDM-1 levels in the river. Pilgrimage areas without adequate waste treatment are possible "hot spots" for AR transmission, and waste treatment must be improved to reduce broader AR dissemination via exposed returning visitors

    A test architecture design for SoCs using ATAM method

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    Test arranging is a basic issue in structure on-a-chip (S.O.C) experiment mechanization. Capable investigation designs constrain the general organization check request time, keep away from analysis reserve conflicts, in addition to purpose of restriction control disseminating in the midst of examination manner. In this broadsheet, we absent a fused method to manage a couple of test arranging issues. We first present a system to choose perfect timetables for sensibly evaluated SOC’s among need associations, i.e., plans that spare alluring orderings among tests. This furthermore acquaints a capable heuristic estimation with plan examinations designed for enormous S.O.Cs through need necessities in polynomial occasion. We portray a narrative figuring with the purpose of uses pre-emption of tests to secure capable date-books in favour of SOCs. Exploratory marks on behalf of an educational S-O-C plus a cutting edge SOC exhibit with the aim of capable investigation timetables be able to subsist gained in sensible CPU occasion

    Constituents of dynamic marketing capability: Strategic fit and heterogeneity in export performance

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    Data availability: Data will be made available on request.Using the Resource Based View and Dynamic Capability theoretical lenses, this paper provides such a strategic treatise in exploring how the underlying dimensions of DMC can be understood within a higher-order DMC strategy and the influence of the latter upon the export performance of firms from an emerging market. The empirical findings drawn from a sample of 315 exporters representing eight industries from Bangladesh show that the DMC is a second-order latent construct consisting of four marketing capabilities: proactive market orientation, brand management capability, new product development capability, and customer relationship management capability. Additionally, this study identified three clusters of firms and showed that, among them, enthusiastic embracers—which are characterized by high levels of activity across marketing capabilities, such as proactive market orientation and brand management capability—achieve better performance

    Concurrent paclitaxel versus cisplatin with external beam radiotherapy in locally advanced head and neck cancer patients: a comparative study

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    Background: The management of locally advanced head and neck cancer (HNC) requires a multidisciplinary approach. With a paradigm shift towards organ preservation, concurrent chemo radiation (CCRT) has taken a more centralized place in the management of HNC. This study aimed to compare the efficacy of CCRT with weekly paclitaxel versus weekly cisplatin in locally advanced squamous cell carcinoma of the head and neck (SCCHN). Methods: This quasi-experimental study was conducted at the Department of Oncology, Khwaja Yunus Ali Medical College and Hospital (KYAMCH), Enayetpur, Sirajganj, from June 2019 to December 2020. A total of 64 patients were selected by purposive sampling technique. Study subjects were divided into 2 arms- arm A and arm B, each arm contained 32 patients. Results: In Arm A, 53.12% showed complete response (CR) whereas in arm B, CR showed 62.5%. Partial response was 31.25% and 28.12% in Arm A & B, respectively. Stable disease was 9.37% & 6.25% in Arm A & B, respectively. Two patients in Arm A and one patient in Arm B showed progressive disease at the final follow-up. The difference was statistically not significant (p>0.05). Conclusions: This study concludes that patients receiving paclitaxel showed comparatively more response to treatment than those receiving cisplatin. So, CCRT by low dose weekly Paclitaxel given in conventional fractionation can be substituted to concurrent Cisplatin in locally advanced SCCHN in terms of efficacy and some manageable local toxicities

    Novel DTC-SVM for an Adjustable Speed Sensorless Induction Motor Drive

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    This paper presents, the direct torque control (DTC) based space vector modulation (SVM) for an adjustable speed sensorless induction motor (IM) drive. This proposed system will give a clear study about DTC and SVM and the motor drive is supplied by a two-level SVPWM inverter. Based on input-output feedback linearization control the inverter reference voltage is obtained, using the IM model in the stator D–Q axes reference frame with stator current and flux vectors components as state variables. Moreover, a robust full-order adaptive stator flux observer is designed for a speed sensorless DTC-SVM system and a new speed-adaptive law is given. By designing the observer gain matrix based on state feedback H  control theory, the stability and robustness of the observer systems is ensured. The speed adaptive stator flux observer stability guaranteed also by the gain matrix in very low speed. The experimental results are proved by simulation results

    Prospects of new chickpea varieties in Andhra Pradesh

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    Andhra Pradesh is an important chickpea growing state in southern India, with spectacular increase in chickpea area from 120,000 ha in 1997/98 to 638,000 ha in 2007/08. The chickpea revolution in Andhra Pradesh has improved the prospects of many resource-poor, small land holding and rainfed farmers of Andhra Pradesh. However, the growing season of chickpea in Andhra Pradesh is warm and short (90-110 days), and drought is the foremost factor responsible for significant yield losses. Rainfall in major chickpea-growing regions is quite uncertain and erratic, resulting in poor yields. The Regional Agricultural Research Station of Acharya N G Ranga Agricultural University, Nandyal, Andhra Pradesh, India is the lead centre responsible for location-specific research in chickpea in Andhra Pradesh. With support from ICRISAT and ICAR, the centre has initiated crop improvement programmes during 2004 and has released four promising chickpea varieties for commercial cultivation. Three desi varieties viz., Nandyal Sanaga 1(NBeG 3), Dheera (NBeG 47), and Nandyal Gram 49 (NBeG 49) released for Andhra Pradesh and one large-seeded kabuli Nandyal Gram 119 (NBeG 119) released for the southern zone comprising Andhra Pradesh, Karnataka and Tamil Nadu, are cutting across chickpea growing regions of Andhra Pradesh. Nandyal Sanaga 1, released in 2012, is a bold-seeded desi variety tolerant to drought and heat; Dheera released during 2015 is also a desi variety and the first of its kind in India, suitable for mechanical harvesting. Nandyal Gram 49 released during 2016 is a highyielding desi variety with attractive seeds; whereas Nandyal Gram 119 is early bold-seeded kabuli variety released during 2015. These varieties have clearly demonstrated their advantage (10%-15 % increase over popular varieties of the tract) in farmers’ holdings in large-scale demonstrations and are being preferred by farmers of not only Andhra Pradesh, but also Karnataka, Tamil Nadu, Odisha and Maharastra. Efforts are underway to promote large-scale adoption of these varieties to maximize long term productivity of chickpeas in rainfed vertisols
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