4,463 research outputs found

    Competing feedback in an idealized tide-influenced delta network

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    The morphodynamic evolution of river deltas is intimately tied to flow and sediment partitioning at bifurcations. In this work, the long-term equilibrium configuration of a simple delta network is investigated by means of an analytical model, which accounts for the effect of small tidal oscillations. Differently from individual bifurcations where tidal action is always a stabilizing factor, in the case of a tree-like delta with multiple bifurcations a dual response emerges. Specifically, depending on the values of four reference parameters functions of tidal amplitude, upstream flow conditions, and channels geometry, tides can either promote or discourage an unbalanced discharge distribution. This behavior primarily concerns the apex bifurcation, which is affected by the variations of the relative tidal amplitude at the internal nodes. In turn these variations depend on how flow and sediment are diverted upstream. The stability of steady-state solutions is found to be governed by the sign and magnitude of the slope asymmetry between channels. This work provides a basic modeling framework for the interpretation of the autogenic response of multiple coupled micro-tidal bifurcations, which can potentially be extended to include in a unified scheme erosional and depositional processes typical of fluvio-deltaic systems

    Minilaparotomy a Good Option in Specific Cases: A Case Report of Bilateral Ovarian Germ Cell Tumor

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    Mature cystic teratomas (MCTs) of the ovary represent 44% of ovarian neoplasmas. The surgical approach is important in young women especially for the cosmetic results. Nowadays most of the ovarian surgeries can be performed laparoscopically. An alternative between laparoscopy and laparotomy is the minilaparotomy (ML) which can be an interesting option, thanks to the small incision. We report a 39-year-old woman who was referred to our hospital with acute abdominal pain. In her past history the patient had an uncomplicated delivery. During pregnancy a 6 cm bilateral MCT was diagnosed and expectant management was followed. A left-sided ovarial torsion was postulated, and laparoscopic detorsion was performed. To avoid a rupture of the left MCT, the operation was interrupted. To remove the cyst, a ML was done two weeks later. A left-sided salpingo-oophorectomy was performed due to a large cyst including the entire ovary. On the other side, the right dermoid cyst was entirely removed. The advantage of a ML is not only shorter operating time with less learning curve compared to laparoscopy but also the possibility to extract the adnexal mass from the abdominal cavity with lower risk of rupture and in addition the possibility to preserve more ovarian tissue

    Analisa Kelayakan Tarif Angkutan Umum Dalam Kota Kupang

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    Penentuan besaran tarif angkutan membutuhkan penanganan dan kebijakan yang arif karena dapat menjembatani kepentingan penumpang selaku konsumen dan pengusaha selaku operator angkutan umum. Penelitian ini bertujuan untuk mengetahui Biaya Operasi Kendaraan (BOK) dan tarif yang layak diberlakukan untuk trayek angkutan umum Kota Kupang dengan jarak terpendek dan jarak terpanjang. Trayek Terminal Kupang-Penfui adalah trayek angkutan Kota Kupang dengan jarak terpanjang (28,30 km) yang melayani kawasan pertokoan, pendidikan dan kawasan Perumahan, sedangkan trayek Terminal Kupang-Perumnas merupakan trayek angkutan kota dengan jarak terpendek (7,68 km) yang melayani kawasan pendidikan dan Perumahan. Kedua trayek ini memiliki penentuan tarif angkutan yang sama yaitu Rp 2000,- untuk pelajar dan Rp 3000,- untuk masyarakat umum. Analisa BOK dan kelayakan tarif dilakukan dengan metode perhitungan berdasarkan Keputusan Direktur Jenderal Perhubungan Darat Nomor: SK.687/AJ.206 /DRJD/2002 tentang Pedoman Teknis Penyelenggaraan Angkutan Penumpang Umum di Wilayah Perkotaan Dalam Trayek Tetap dan Teratur. Hasil analisa BOK untuk trayek Terminal Kupang-Penfui sebesar Rp 2.165,42/penumpang dan tarif yang layak diberlakukan sebesar Rp 2.381,96/penumpang, sedangkan BOK untuk trayek Terminal Kupang-Perumnas sebesar Rp 1.956,31/penumpang dan tarif yang layak diberlakukan sebesar Rp 2.151,94/penumpang. Determining the amount of transport fares require wise policy for it can bridge the interests of passengers as consumers and businessman as public transport operators. This study aims to determine the Vehicle Operating Cost (VOC) and the decent fares applied in Kupang City for the shortest and the longest route. The route of Terminal Kupang-Penfui is the longest ones that has a distance of 28.30 km, that serves the shopping area and the educational and residential areas; while the route of Terminal Kupang-Perumnas is the shortest route (7.68 km) which serves educational and residential area. Nowadays these two routes have the same transport fares is Rp. 2000, - for students and Rp 3,000, - for public in general. VOC and feasibility fare analysis conducted by the method of the Directorate General of Land Transportation No. SK.687/AJ.206/DrJD/2002. The VOC analysis results for Terminal Kupang-Penfui route is Rp. 2165.42 / passenger and the decent fare imposed is Rp. 2381.96 / passenger; while the VOC for Terminal Kupang-Perumnas is Rp 1956.31 / passenger and the decent fare imposed is Rp. 2151.94 / passenger

    Design of qos-aware energy-efficient fiber–wireless access networks

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    Energy-efficient network design has recently become a very important topic because of the energy cost increases in service providers’ infrastructures. This is of particular importance in access networks because of the growing demand for digital traffic by end users. Here we address the challenge of reducing the energy consumption of fiber–wireless (FiWi) access networks, that use both optical and radio frequency technologies to provide high bandwidth and ubiquity for end-user applications, while keeping delay under a threshold. Our goal is to find optimal sleep mode schedulings that allow energy consumption to be reduced while keeping packet delay acceptable. For this purpose a mathematical formalization and an algorithm are developed. The results show that the proposed approach is able to reduce the average packet delay, with negligible energy cost increases, in many scenarios, besides being computationally efficient and scalable. The proposed approach may, therefore, serve as a basis for planning and design of quality of service-aware energy-efficient FiWi access networks.This work was supported by FCT (Foundation for Science and Technology) of Portugal within CEOT (Center for Electronic, Optoelectronic and Telecommunications)

    Migrant pathways to community mental health centres in Italy.

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    Background: Many studies indicate that migrants in western countries have limited access to and low utilization of community mental health centres (CMHCs) despite the high prevalence of mental disorders. Aims: We aimed to compare migrant pathways to care across four CMHCs located in different Italian provinces and to identify pathway to care predictors. Methods: Migrants attending the four CMHCs between 1 July 1999 and 31 December 2007 were included in the study. Data were gathered retrospectively from clinical data sets and chart review. Results: Five hundred and eleven (511) migrants attended the four CMHCs, 61% were referred by GPs or other health services and 39% followed non-medical pathways to care (self-referral or through social and voluntary organizations), with important site variations. Younger age and being married were predictors of medical pathways to care; lacking a residence permit and having a diagnosis of substance abuse were related to non-medical pathways. Conclusions: Pathways to CMHCs are complex and influenced by many factors. Non-medical pathways to care seem to be frequent among migrants in Italy. More attention should be paid to developing psychiatric consultation liaison models that also encompass the social services and voluntary organizations

    Impact of hormonal treatment duration in combination with radiotherapy for locally advanced prostate cancer: Meta-analysis of randomized trials

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    <p>Abstract</p> <p>Background</p> <p>Hormone therapy plus radiotherapy significantly decreases recurrences and mortality of patients affected by locally advanced prostate cancer. In order to determine if difference exists according to the hormonal treatment duration, a literature-based meta-analysis was performed.</p> <p>Methods</p> <p>Relative risks (RR) were derived through a random-effect model. Differences in primary (biochemical failure, BF; cancer-specific survival, CSS), and secondary outcomes (overall survival, OS; local or distant recurrence, LR/DM) were explored. Absolute differences (AD) and the number needed to treat (NNT) were calculated. Heterogeneity, a meta-regression for clinic-pathological predictors and a correlation test for surrogates were conducted.</p> <p>Results</p> <p>Five trials (3,424 patients) were included. Patient population ranged from 267 to 1,521 patients. The longer hormonal treatment significantly improves BF (with significant heterogeneity) with an absolute benefit of 10.1%, and a non significant trend in CSS. With regard to secondary end-points, the longer hormonal treatment significantly decrease both the LR and the DM with an absolute difference of 11.7% and 11.5%. Any significant difference in OS was observed. None of the three identified clinico-pathological predictors (median PSA, range 9.5-20.35, Gleason score 7-10, 27-55% patients/trial, and T3-4, 13-77% patients/trial), did significantly affect outcomes. At the meta-regression analysis a significant correlation between the overall treatment benefit in BF, CSS, OS, LR and DM, and the length of the treatment was found (p≤0.03).</p> <p>Conclusions</p> <p>Although with significant heterogeneity (reflecting different patient' risk stratifications), a longer hormonal treatment duration significantly decreases biochemical, local and distant recurrences, with a trend for longer cancer specific survival.</p

    Migrant pathways to community mental health centres in Italy.

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    Background: Many studies indicate that migrants in western countries have limited access to and low utilization of community mental health centres (CMHCs) despite the high prevalence of mental disorders. Aims: We aimed to compare migrant pathways to care across four CMHCs located in different Italian provinces and to identify pathway to care predictors. Methods: Migrants attending the four CMHCs between 1 July 1999 and 31 December 2007 were included in the study. Data were gathered retrospectively from clinical data sets and chart review. Results: Five hundred and eleven (511) migrants attended the four CMHCs, 61% were referred by GPs or other health services and 39% followed non-medical pathways to care (self-referral or through social and voluntary organizations), with important site variations. Younger age and being married were predictors of medical pathways to care; lacking a residence permit and having a diagnosis of substance abuse were related to non-medical pathways. Conclusions: Pathways to CMHCs are complex and influenced by many factors. Non-medical pathways to care seem to be frequent among migrants in Italy. More attention should be paid to developing psychiatric consultation liaison models that also encompass the social services and voluntary organizations
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