484 research outputs found

    Dynamic lot sizing and tool management in automated manufacturing systems

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    Cataloged from PDF version of article.The overall aim of this study is to show that there is a critical interface between the lot sizing and tool management decisions, and these two problems cannot be viewed in isolation. We propose "ve alternative algorithms to solve lot sizing, tool allocation and machining conditions optimization problems simultaneously. The "rst algorithm is an exact algorithm which "nds the global optimum solution, and the others are heuristics equipped with a look-ahead mechanism to guarantee at least local optimality. The computational results indicate that the amount of improvement is statistically signi"cant for a set of randomly generated problems. The magnitude of cost savings is dependent on the system parameters

    Principles of practice parameters for the treatment of sleep disordered breathing in the elderly and frail elderly: the consensus of the International Geriatric Sleep Medicine Task Force

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    Sleep disordered breathing (SDB) is a leading cause of morbidity worldwide. Its prevalence increases with age. Due to the demographic changes in industrial societies, pulmonologists and sleep physicians are confronted with a rapidly growing number of elderly SDB patients. For many physicians, it remains unclear how current guidelines for SDB management apply to elderly and frail elderly patients. The goal of this consensus statement is to provide guidance based on published evidence for SDB treatment in this specific patient group. Clinicians and researchers with expertise in geriatric sleep medicine representing several countries were invited to participate in a task force. A literature search of PubMed from the past 12 years and a systematic review of evidence of studies deemed relevant was performed. Recommendations for treatment management of elderly and frail elderly SDB patients based on published evidence were formulated via discussion and consensus. In the last 12 years, there have been surprisingly few studies examining treatment of SDB in older adults and even fewer in frail older adults. Studies that have been conducted on the management of SDB in the older patient population were rarely stratified for age. Studies in SDB treatment that did include age stratification mainly focused on middle-aged and younger patient groups. Based on the evidence that is available, this consensus statement highlights the treatment forms that can be recommended for elderly SDB patients and encourages treatment of SDB in this large patient group

    Impact on visual acuity in neovascular age related macular degeneration (Namd) in europe due to covid-19 pandemic lockdown

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    This is a retrospective, multicenter study of consecutive patients with nAMD scheduled for a visit and/or a treatment with an intravitreal injection (IVI) during the 3 months before lockdown in the Ophthalmology Departments of six centers of Europe.The study was conducted on 546 patients, of which 55.13% were females, almost 100% of the patients were White/Caucasian race, and 71.53% of the patients presented a type 1 macular neovascularization (NVM). A total of 62.82% of patients (343 patients) that were on scheduled clinic visits and/or intravitreal injection treatment during the 3 months before the quarantine did not attend either to visit or for treatment during the lockdown. The mean number of injections during the lockdown was significantly reduced. This was followed by a significant reduction in the mean best-corrected visual acuity (BCVA) between the 3 months before the lockdown (mean BCVA of 60.68 ± 19.77 letters) and 6 months after lockdown (mean BCVA of 56.98 ± 22.59 letters). Patients with better BCVA before the lockdown and the ones showing neovascular activity were more likely to attend their scheduled visits and/or IVI treatments. The COVID-19 pandemic and the lockdown have led to a decrease in the number of IVI treatments in patients with nAMD, evidencing a significant vision loss at 6 months

    Site fidelity of Hippocampus guttulatus Cuvier, 1829 at Mar Piccolo of Taranto (Southern Italy; Ionian Sea)

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    Lack of detailed knowledge on ecological niche, life cycles, spatial distribution, reproductive biology and space use strongly affects the selection of useful tools and measures in the conservation of threatened marine species. Especially for sedentary and slow species, behaviour and movement capacities are supposed to be the most important functional traits. Indeed, behavioural variability concerning available space and the close presence of individuals is considered a crucial trait for the population dynamics assessments, especially when disturbances of various causes are present in the environment. The present study aimed to investigate the site fidelity and degree of movement of Hippocampus guttulatus, an emblematic and threatened Mediterranean seahorse species. With this aim, a number of seahorses were tagged and monitored throughout two years within a limited area of the lagoon of Mar Piccolo of Taranto (Southern Italy). The studied individuals were initially morphometrically measured for size, sex and life-cycle stage and subsequently monitored through repeated four-month surveys each year. Obtained results indicated high site fidelity regardless of habitat type. Movement pattern was in line with the data on congeneric species, although values were slightly higher. The analyses showed differences in movement degree among different sexes and life-cycle stages and indicated greater mobility of adult females compared to males and juveniles. The investigated parameters showed a great variability suggesting that even small-scale environmental factors can influence the species mobility. Finally, a change in the population structure has been observed, with the loss of large individuals in 2016 and reduced recruitment in 2017. These findings indicated the possible presence of stressors that could lead to the alteration of the seahorse population at Mar Piccolo of Taranto

    The prevalence of serum antibodies to tick-borne infections in Mbale District, Uganda: The effect of agro-ecological zone, grazing management and age of cattle

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    Between August and October 2000, a cross-sectional study was conducted in smallholder dairy farms in Mbale District, Uganda to assess the prevalence of ticks and tick-borne diseases under different grazing systems and agro-ecological zones and understand the circumstances under which farmers operated. A questionnaire was administered to obtain information on dairy farm circumstances and practices. A total of 102 farms were visited and sera and ticks were collected from 478 animals. Sero-prevalence of tick-borne diseases was determined using an enzyme-linked immunoassay. Acaricides were used indiscriminately but the intensity of their use varied with the grazing system and zone. Cattle from different farms mixed for various reasons. During the dry seasons farmers have to get additional fodder from outside their farms that can result in importation of ticks. The prevalence of ticks and serum antibodies to tick-borne infections differed across the grazing systems and zones. The highest serum antibody prevalence (>60%) was recorded in the lowland zone under the free range and tethering grazing systems. The lowest tick challenge and serum antibody levels (<50%) were recorded in the midland and upland zones under a zero-grazing system. These findings suggest that endemic stability to East Coast Fever, babesiosis and anaplasmosis is most likely to have existed in the lowland zone, particularly, under the tethering and free-range grazing systems. Also, endemic stability for babesiosis existed in the upland zones. Endemic instability for East Coast Fever existed in the midland and upland zones. These structured observational studies are instrumental in planning of control strategies for ticks and tick borne diseases since production systems and the cattle population at high risk of the diseases in the district have been identified. Abbreviation: / zone: agro-ecological zon

    Predatory and competitive interaction in Anopheles gambiae sensu lato larval breeding habitats in selected villages of central Uganda.

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    BACKGROUND: Malaria is often persistent in communities surrounded by mosquito breeding habitats. Anopheles gambiae sensu lato exploit a variety of aquatic habitats, but the biotic determinants of its preferences are poorly understood. This study aimed to identify and quantify macroinvertebrates in different habitat types with determined water physico-chemical parameters to establish those preferred by An. gambiae s.l. larvae as well as their predators and competitors. METHODS: A field survey was conducted in Kibuye and Kayonjo villages located in the vicinity of the River Sezibwa, north-eastern Uganda to identify Anopheline larval habitats shared by aquatic insects. Habitats were geo-recorded and as streams, ponds, temporary pools and roadside ditches. From October to December 2017, random microhabitats/quadrats were selected from each habitat type, their water physico-chemical parameters (electrical conductivity, total dissolved solids, temperature and pH) were measured, and they were sampled for macroinvertebrates using standard dippers. All collected arthropod macroinvertebrates were then morphologically identified to family level and enumerated. RESULTS: Principal component analysis showed that the four larval habitat types were characterized by distinct physico-chemical parameter profiles. Ponds and streams had the highest number and diversity of macroinvertebrate insect taxa and sustained few An. gambiae s.l. larvae. Anopheles gambiae s.l. were more common in roadside ditches and particularly abundant in temporary pools which it commonly shared with Dytiscidae (predaceous diving beetles) and Culex spp. Cluster correlation analysis conducted on the abundance of these taxa within quadrats suggested that An. gambiae s.l. and Dytiscidae have the most similar patterns of microhabitat use, followed by Cybaeidae (water spiders). Whilst Culex spp. co-occurred with An. gambiae s.l. in some habitats, there was only partial niche overlap and no clear evidence of competition between the two mosquito taxa. CONCLUSIONS: Ponds and streams are habitats that host the largest diversity and abundance of aquatic insect taxa. Anopheles gambiae s.l. larvae distinctively preferred temporary pools and roadside ditches, where they were exposed to few predators and no apparent competition by Culex spp. Further studies should aim to test the impact of Dytiscidae and Cybaeidae on An. gambiae s.l. dynamics experimentally

    Alcohol Use and its Associated Factors among Residents of an Urban Community in Plateau State Nigeria

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    Background:According to the World Health Organization (WHO), alcohol use contributes about 2.3 million deaths globally and accounts for 3.8% of global mortality. Nigeria ranks as the leading country in alcohol consumption in Africa. In view of this, this study was conducted to assess the level of alcohol use and its associated factors among residents of an urban community in Plateau state, Nigeria.Methodology: A cross sectional study carried outnbsp among 212 adult residents of AngwanRukuba community of Jos North Local Government Area of Plateau Statenbsp using quantitative method of data collection.nbsp Epi info statistical software version 7.0 was used for data analysis with adjusted odds ratio and 95% confidence intervalused in the study while a p-value of le 0.05 was considered statistically significant.Result: The average age of the respondents in this study was 28.2plusmn10.4 years with majority being 30 years and below. More of the respondents 142(60.8%) were current consumers of alcoholic drinks with harmful level of alcohol intake found to be 32.0%.Sex, quantity of drinks adjudged as normal in one sitting and age of onset of alcohol use were found to significantly predict harmful intake of alcohol containing drinks in the study.Conclusion: A relatively high level of alcohol use was found in this study with a corresponding level of harmful use. Sex, age of onset of alcohol use and quantity of drinks adjudged as normal in a sitting were significant contributors to harmful alcohol use.nbs

    The False Economy of Seeking to Eliminate Delayed Transfers of Care: Some Lessons from Queueing Theory

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    This is the final version. Available on open access from Springer via the DOI in this recordBackground It is a stated ambition of many healthcare systems to eliminate delayed transfers of care (DTOCs) between acute and step-down community services. Objective This study aims to demonstrate how, counter to intuition, pursual of such a policy is likely to be uneconomical, as it would require large amounts of community capacity to accommodate even the rarest of demand peaks, leaving much capacity unused for much of the time. Methods Some standard results from queueing theory—a mathematical discipline for considering the dynamics of queues and queueing systems—are used to provide a model of patient flow from the acute to community setting. While queueing models have a track record of application in healthcare, they have not before been used to address this question. Results Results show that ‘eliminating’ DTOCs is a false economy: the additional community costs required are greater than the possible acute cost saving. While a substantial proportion of DTOCs can be attributed to inefficient use of resources, the remainder can be considered economically essential to ensuring cost-efficient service operation. For England’s National Health Service (NHS), our modelling estimates annual cost savings of £117m if DTOCs are reduced to the 12% of current levels that can be regarded as economically essential. Conclusion This study discourages the use of ‘zero DTOC’ targets and instead supports an assessment based on the specific characteristics of the healthcare system considered.Health Data Research U

    Renal and suprarenal insufficiency secondary to familial Mediterranean fever associated with amyloidosis: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Familial Mediterranean fever is an autosomal recessive disease that predominantly affects people of the Mediterranean coast. One of the most frequent complications of the disease is amyloidosis. This clinical entity is known as secondary (also called AA) amyloidosis.</p> <p>Case presentation</p> <p>In this report, we describe the case of a 33-year-old Turkish man with familial Mediterranean fever and chronic renal insufficiency. He was admitted to our clinic with symptoms of suprarenal insufficiency. The patient died three months later as a result of cardiac arrest.</p> <p>Conclusion</p> <p>Our aim is to make a contribution to the literature by reporting a case of combined insufficiency due to the accumulation of renal and adrenal amyloid in a patient with familial Mediterranean fever, which has very rarely been described in the literature. We hope that adrenal insufficiency, which becomes fatal if not diagnosed and treated rapidly, will come to mind as easily as chronic renal failure in clinical practice.</p
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