86 research outputs found

    Resource management in IP-based radio access networks

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    IP is being considered to be used in the Radio Access Network (RAN) of UMTS. It is of paramount importance to be able to provide good QoS guarantees to real time services in such an IP-based RAN. QoS in IP networks is most efficiently provided with Differentiated services (Diffserv). However, currently Diffserv mainly specifies Per Hop Behaviors (PHB). Proper mechanisms for admission control and resource reservation have not yet been defined. A new resource management concept in the IP-based RAN is needed to offer QoS guarantees to real time services. We investigate the current Diffserv mechanisms and contribute to development of a new resource management protocol. We focus on the load control algorithm [9], which is an attempt to solve the problem of admission control and resource reservation in IP-based networks. In this document we present some load control issues and propose to enhance the load control protocol with the Measurement Based Admission Control (MBAC) concept. With this enhancement the traffic load in the IP-based RAN can be estimated, since the ingress router in the network path can be notified by marking packets with the resource state information. With this knowledge, the ingress router can perform admission control to keep the IP-based RAN stable with a high utilization even in overload situations

    Techno-economic Analysis of a Wind-Diesel Hybrid Power System in the South Algeria

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    The electrical energy is often produced with the help of diesel generators in isolated areas in the Saharan region. While the latter requiring relatively little investment because is generally expensive to exploit due to the transportation to remote areas adds extra cost, significant fuel consumption and relatively high maintenance cost, etc. Moreover, the electricity production by the diesel is ineffective, presents significant environmental risks. But these isolated areas have significant wind energy potential; which is good position for the exploitation of clean and sustainable wind energy. The use of wind-diesel power system is widely recommended especially to reduce fuel consumption and in this way to reduce system operating costs and environmental impact. The subject of this paper is to present the techno-economic analysis of a wind-diesel hybrid power system. In this context, the contribution envisaged with this research is to collaborate on the optimal design of a hybrid power system including a wind turbine generator, a diesel generator and an energy storage system for powering a continuous way an isolated site in the South Algerian installed power of 120 kW.This system has a high control strategy for the management of different power sources (wind, diesel, battery) that depending to weather conditions, especially wind speed values and the power demanded by the consumer load

    Environmental and neuroendocrine control of breeding activity in the dromedary camel

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    The dromedary camel (Camelus dromedarius), a well-adapted desert mammal, is a seasonal breeder whose sexual activity occurs during the winter and spring. These periods coincide with food resources and climate conditions are favorable for offspring’s survival. The mechanisms involved in the control of this seasonality however still need to be elucidated. The aim of this review is to describe the reproductive patterns of the dromedary camel. This includes the geographical seasonal breeding distribution of this species taking into account the role of various physical environmental parameters notably temperature, day length and the amount of rainfall. Further, various aspects of seasonal breeding in male and female camels are discussed as well as the neuroendocrine factors that may control seasonal such phenomena. Finally, the putative roles of two hypothalamic neuropeptides, kisspeptin and (Arg) (Phe) related peptide, are proposed for the control of camel’s seasonal reproduction

    Le contrĂŽle environnemental et neuroendocrinien de l’activitĂ© saisonniĂšre de la reproduction chez le dromadaire

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    Le dromadaire (Camelus dromedarius), qui est un mammifĂšre bien adaptĂ© au dĂ©sert est une espĂšce Ă  reproduction saisonniĂšre. Sa saison sexuelle a lieu durant l’hiver et le printemps. Ces pĂ©riodes coĂŻncident avec l’abondance des ressources alimentaires et des conditions climatiques favorables pour la survie de la progĂ©niture. Toutefois les mĂ©canismes impliquĂ©s dans le contrĂŽle de cette saisonnalitĂ© restent encore mal Ă©lucidĂ©s. L’objectif de cette revue est de dĂ©crire les caractĂ©ristiques de la reproduction chez le dromadaire. Cela inclue la distribution gĂ©ographique de sa saison sexuelle et son dĂ©clenchement possible par plusieurs paramĂštres environnementaux physiques, notamment la tempĂ©rature ambiante, la photopĂ©riode et la quantitĂ© de prĂ©cipitations. De plus, plusieurs aspects de cette saisonnalitĂ© ont Ă©tĂ© discutĂ©s chez le mĂąle et la femelle. Finalement, cette revue analyse les facteurs neuroendocriniens impliquĂ©s dans la saisonnalitĂ© de reproduction, notamment, le rĂŽle putatif de deux neuropeptides hypothalamiques, le kisspeptin et le (Arg) (Phe) peptide apparentĂ©. Mots-clĂ©s: Dromadaire, saisonnalitĂ© de reproduction, prĂ©cipitations, photopĂ©riode, tempĂ©rature ambiante, disponibilitĂ© alimentaire, kisspeptin, RFRP. The dromedary camel (Camelus dromedarius), a well-adapted desert mammal, is a seasonal breeder whose sexual activity occurs during the winter and spring. These periods coincide with food resources and climate conditions are favorable for offspring’s survival. The mechanisms involved in the control of this seasonality however still need to be elucidated. The aim of this review is to describe the reproductive patterns of the dromedary camel. This includes the geographical seasonal breeding distribution of this species taking into account the role of various physical environmental parameters notably temperature, day length and the amount of rainfall. Further, various aspects of seasonal breeding in male and female camels are discussed as well as the neuroendocrine factors that may control seasonal such phenomena. Finally, the putative roles of two hypothalamic neuropeptides, kisspeptin and (Arg) (Phe) related peptide, are proposed for the control of camel’s seasonal reproduction. Keywords: Dromedary camel, seasonal breeding, rainfall, photoperiod, ambient temperature, food availability, Kisspeptin, RFRP

    COMPLICATIONS RETINIENNES DES ANTIPALUDEENS DE SYNTHESE. A PROPOS DE 2 CAS

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    Treatment with the antimalarials chloroquine or hydroxychloroquine is frequently used in dermatology and rheumatology. However irreversible retinal damage can occurs, that’s why intensive monitoring is still required. We report 2 cases of females patients aged of 33 and 42 years old, treated by antimalarials for polyarthritis and sclerodermia. After 4 years of treatment without ophthalmologic examination, they complain of decreased vision. The fundoscopic exam found a bilateral bull's eye appearence confirmed by fluorescein angiography. Even after cessation of treatment the visual acuity didn’t increase.Ocular toxicity of antimalarials treatment is rare but it can occurs. The retinopathy is the major concern. We found three stages: asymptomatic, obvious maculopathy and advanced retinopathy. Appropriate examinations (color vision, automatic visual field and electroretinogram) should be performed regularly. The frequency of screening should be based on patients’ classification.Les antipaludĂ©ens de synthĂšse sont largement utilisĂ©s en rhumatologie et en dermatologie pour leur action anti-inflammatoire. Ils exposent toute fois Ă  des complications rĂ©tiniennes irrĂ©versibles d’oĂč la nĂ©cessitĂ© d’une surveillance ophtalmologique rĂ©guliĂšre. Nous rapportons l’observation de deux patientes ĂągĂ©es de 33 et 42 ans, mises sous antipaludĂ©ens de synthĂšse respectivement pour une polyarthrite rhumatoĂŻde et une sclĂ©rodermie. Elles ont poursuivies leur traitement pendant 3 Ă  4 ans sans surveillance ophtalmologique avant de consulter pour une baisse importante de l’acuitĂ© visuelle. L’examen ophtalmologique a retrouvĂ© une acuitĂ© visuelle infĂ©rieure Ă  2/10Ăšme dans le premier cas et une acuitĂ© visuelle infĂ©rieure Ă  6/10Ăšme dans le deuxiĂšme cas ; avec au fond d’oeil un aspect de maculopathie bilatĂ©rale en oeil de boeuf typique confirmĂ©e par l’angiographie rĂ©tinienne Ă  la fluoresceine. MalgrĂ© l’arrĂȘt des antipaludĂ©ens de synthĂšse, l’acuitĂ© visuelle est restĂ©e stationnaire dans les deux cas. L’intoxication clinique aux antipaludĂ©ens de synthĂšse est rare mais possible. Elle prĂ©domine dans la rĂ©gion maculaire et Ă©volue en 3 stades: asymptomatique, maculopathie confirmĂ©e et stade de rĂ©tinopathie Ă©voluĂ©e. Un bilan ophtalmologique initial doit ĂȘtre fait systĂ©matiquement, avant le dĂ©but du traitement avec rĂ©alisation d’examens paracliniques (vision des couleurs, champs visuel automatisĂ©, Ă©lectrorĂ©tinographie maculaire). Au terme des ces examens les patients seront classĂ©s en trois groupes permettant ainsi de dĂ©terminer leur rythme de surveillance

    LES UVEITES DE L’ENFANT : A PROPOS DE 30 CAS

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    Uveitis is less frequent in children. The purpose of our study is to evaluate epidemiologic aspect, etiological profile and prognosis of children uveitis.We report 30 cases of uveitis in patients aged less than 16 years old followed in our department.Patients mean age is 9 years old (5 to 16 years) .We observed anterior uveitis in 46,7%, posterior uveitis in 26,7%, intermediate uveitis in 13,3% and panuveitis in 13,3%.Chronic juvenile arthritis is the main etiology followed by Behcet disease.Uveitis in children is rare but severe and can involve visual prognosis; it needs urgent diagnosis and adapted treatment. Principals etiologies are; idiopathic juvenile arthritis and spondiloarthropaties. Functional prognosis is variable and final visual acuity is less than 20/200 in 16 to 36% of cases.L’uvĂ©ite de l’enfant est rare. Le but de notre travail est d’évaluer le profil Ă©pidĂ©miologique, Ă©tiologique et pronostic des uvĂ©ites de l’enfant.Nous rapportons 30 cas d’uvĂ©ites chez des patients d’ñge infĂ©rieur Ă  16 ans et suivis dans notre unitĂ©.La moyenne d’ñge des patients est de 9 ans (5 Ă  16 ans). Il s’agissait d’une uvĂ©ite antĂ©rieure dans 46,7% des cas, d’une uvĂ©ite postĂ©rieure dans 26,7%, d’une uvĂ©ite intermĂ©diaire dans 13,3% et d’une panuvĂ©ite dans 13,3%. Les principales causes retrouvĂ©es sont l’arthrite juvĂ©nile idiopathique suivie par la maladie de Behçet.L’uvĂ©ite de l’enfant est rare souvent grave engageant le pronostic visuel et imposant un diagnostic prĂ©coce et un traitement adaptĂ©. Les principales Ă©tiologies sont l’arthrite juvĂ©nile idiopathique et les spondyloarthropathies. Le pronostic visuel est variable et l’acuitĂ© visuelle est infĂ©rieure Ă  20/200 dans 16 Ă  36% des cas

    Genome-wide identification, characterization, and validation of the bHLH transcription factors in grass pea

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    Background: The basic helix-loop-helix (bHLH) transcription factor is a vital component in plant biology, with a significant impact on various aspects of plant growth, cell development, and physiological processes. Grass pea is a vital agricultural crop that plays a crucial role in food security. However, the lack of genomic information presents a major challenge to its improvement and development. This highlights the urgency for deeper investigation into the function of bHLH genes in grass pea to improve our understanding of this important crop.Results: The identification of bHLH genes in grass pea was performed on a genome-wide scale using genomic and transcriptomic screening. A total of 122 genes were identified as having conserved bHLH domains and were functionally and fully annotated. The LsbHLH proteins could be classified into 18 subfamilies. There were variations in intron-exon distribution, with some genes lacking introns. The cis-element and gene enrichment analyses showed that the LsbHLHs were involved in various plant functions, including response to phytohormones, flower and fruit development, and anthocyanin synthesis. A total of 28 LsbHLHs were found to have cis-elements associated with light response and endosperm expression biosynthesis. Ten conserved motifs were identified across the LsbHLH proteins. The protein-protein interaction analysis showed that all LsbHLH proteins interacted with each other, and nine of them displayed high levels of interaction. RNA-seq analysis of four Sequence Read Archive (SRA) experiments showed high expression levels of LsbHLHs across a range of environmental conditions. Seven highly expressed genes were selected for qPCR validation, and their expression patterns in response to salt stress showed that LsbHLHD4, LsbHLHD5, LsbHLHR6, LsbHLHD8, LsbHLHR14, LsbHLHR68, and LsbHLHR86 were all expressed in response to salt stress.Conclusion: The study provides an overview of the bHLH family in the grass pea genome and sheds light on the molecular mechanisms underlying the growth and evolution of this crop. The report covers the diversity in gene structure, expression patterns, and potential roles in regulating plant growth and response to environmental stress factors in grass pea. The identified candidate LsbHLHs could be utilized as a tool to enhance the resilience and adaptation of grass pea to environmental stress

    Daily regulation of body temperature rhythm in the camel (Camelus dromedarius) exposed to experimental desert conditions.

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    In the present work, we have studied daily rhythmicity of body temperature (Tb) in Arabian camels challenged with daily heat, combined or not with dehydration. We confirm that Arabian camels use heterothermy to reduce heat gain coupled with evaporative heat loss during the day. Here, we also demonstrate that this mechanism is more complex than previously reported, because it is characterized by a daily alternation (probably of circadian origin) of two periods of poikilothermy and homeothermy. We also show that dehydration induced a decrease in food intake plays a role in this process. Together, these findings highlight that adaptive heterothermy in the Arabian camel varies across the diurnal light-dark cycle and is modulated by timing of daily heat and degrees of water restriction and associated reduction of food intake. The changed phase relationship between the light-dark cycle and the Tb rhythm observed during the dehydration process points to a possible mechanism of internal desynchronization during the process of adaptation to desert environment. During these experimental conditions mimicking the desert environment, it will be possible in the future to determine if induced high-amplitude ambient temperature (Ta) rhythms are able to compete with the zeitgeber effect of the light-dark cycle.journal article2014 Sep 012014 09 28importe

    Genome-wide analysis identified candidate variants and genes associated with heat stress adaptation in Egyptian sheep breeds

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    Heat stress caused by climatic changes is one of the most significant stresses on livestock in hot and dry areas. It has particularly adverse effects on the ability of the breed to maintain homeothermy. Developing countries are advised to protect and prepare their animal resources in the face of potential threats such as climate change. The current study was conducted in Egypt’s three hot and dry agro-ecological zones. Three local sheep breeds (Saidi, Wahati, and Barki) were studied with a total of 206 ewes. The animals were exercised under natural heat stress. The heat tolerance index of the animals was calculated to identify animals with high and low heat tolerance based on their response to meteorological and physiological parameters. Genomic variation in these breeds was assessed using 64,756 single nucleotide polymorphic markers (SNPs). From the perspective of comparative adaptability to harsh conditions, our objective was to investigate the genomic structure that might control the adaptability of local sheep breeds to environmental stress under hot and dry conditions. In addition, indices of population structure and diversity of local breeds were examined. Measures of genetic diversity showed a significant influence of breed and location on populations. The standardized index of association (rbarD) ranged from 0.0012 (Dakhla) to 0.026 (Assuit), while for the breed, they ranged from 0.004 (Wahati) to 0.0103 (Saidi). The index of association analysis (Ia) ranged from 1.42 (Dakhla) to 35.88 (Assuit) by location and from 6.58 (Wahati) to 15.36 (Saidi) by breed. The most significant SNPs associated with heat tolerance were found in the MYO5A, PRKG1, GSTCD, and RTN1 genes (p ≀ 0.0001). MYO5A produces a protein widely distributed in the melanin-producing neural crest of the skin. Genetic association between genetic and phenotypic variations showed that OAR1_18300122.1, located in ST3GAL3, had the greatest positive effect on heat tolerance. Genome-wide association analysis identified SNPs associated with heat tolerance in the PLCB1, STEAP3, KSR2, UNC13C, PEBP4, and GPAT2 genes

    Baseline new bone formation does not predict bone loss in ankylosing spondylitis as assessed by quantitative computed tomography (QCT) - 10-year follow-up

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    <p>Abstract</p> <p>Background</p> <p>To evaluate the relationship between bone loss and new bone formation in ankylosing spondylitis (AS) using 10-year X-ray, dual-energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT) follow-up.</p> <p>Methods</p> <p>Fifteen AS patients free from medical conditions and drugs affecting bone metabolism underwent X-ray, DXA and QCT in 1999 and 2009.</p> <p>Results</p> <p>In spine QCT a statistically significant (p = 0,001) decrease of trabecular bone mineral content (BMC) was observed (change ± SD: 18.0 ± 7.3 mg/cm<sup>3</sup>). In contrast, spine DXA revealed a significant increase of bone mineral density (change ± SD: -0.15 ± 0.14 g/cm<sup>2</sup>). The mean BMC, both at baseline and follow-up was significantly lower (p = 0.02 and p = 0.005, respectively) in advanced radiological group as compared to early radiological group. However, in multiple regression model after adjustment for baseline BMC, the baseline radiological scoring did not influence the progression of bone loss as assessed with QCT (p = 0.22, p for BMC*X-ray syndesmophyte scoring interaction = 0.65, p for ANOVA-based X-ray syndesmophyte scoring*time interaction = 0.39). Baseline BMC was the only significant determinant of 10-year BMC change, to date the longest QCT follow-up data in AS.</p> <p>Conclusions</p> <p>In AS patients who were not using antiosteoporotic therapy spine trabecular bone density evaluated by QCT decreased over 10-year follow-up and was not related to baseline radiological severity of spine involvement.</p
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