4,746 research outputs found

    Autosomal recessive primary microcephaly: an analysis of locus heterogeneity and phenotypic variation

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    BACKGROUND AND OBJECTIVES: Locus heterogeneity is well established in autosomal recessive primary microcephaly (MCPH) and to date five loci have been mapped. However, the relative contributions of these loci have not been assessed and genotype-phenotype correlations have not been investigated. DESIGN: A study population of 56 consanguineous families resident in or originating from northern Pakistan was ascertained and assessed by the authors. A panel of microsatellite markers spanning each of the MCPH loci was designed, against which the families were genotyped. RESULTS: The head circumference of the 131 affected subjects ranged from 4 to 14 SD below the mean, but there was little intrafamilial variation among affecteds (± 1 SD). MCPH5 was the most prevalent, with 24/56 families consistent with linkage; 2/56 families were compatible with linkage to MCPH1, 10/56 to MCPH2, 2/56 to MCPH3, none to MCPH4, and 18/56 did not segregate with any of the loci. CONCLUSIONS: MCPH5 is the most common locus in this population. On clinical grounds alone, the phenotype of families linked to each MCPH locus could not be distinguished. We have also shown that further MCPH loci await discovery with a number of families as yet unlinked

    The co-creation of social ventures through bricolage, for the displaced, by the displaced

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    Purpose Although scholars have investigated how social entrepreneurs create and develop social enterprises in the penurious stable environment, how they are created in the penurious unstable environment has yet been overlooked. The purpose of this paper is to address this research gap by exploring how internally displaced individuals, despite the lack of resources, create and develop a social enterprise to serve the other displaced population in the war and conflict zones. Design/methodology/approach Underpinned by a biographical research design, in-depth interviews with internally displaced individuals who have created social enterprises in the war and conflict zones were undertaken. Three social entrepreneurs were chosen for this study from three different social enterprises that are created by internally displaced individuals to serve the other internally displaced people of three different countries, namely, Pakistan, Afghanistan and Syria. Findings The single and cross-case analysis found that internally displaced individuals deploy bricolage strategy, for example, reconfiguration of pre-existing resources and competencies (both internal and external), to start up a social venture in the war and conflict zones. They utilise pre-existing internal resources, mainly human capital, and external resources, through a frugal approach towards resources acquisitions. The authors also found that the displaced social entrepreneurs utilise resources of other displaced individuals, for example, networks, volunteers, local knowledge and financial supports mainly from older arrivals, and develop their own enterprise ecosystem within the host location to co-create and co-develop social enterprise and social values for all of them. Research limitations/implications The findings show that internally displaced individuals utilise bricolage strategies to create and develop socially entrepreneurial venture to serve other internally displaced individuals in the war and conflict zones. As the findings are based on three case studies, for confirmatory approach, a quantitative study with a large sample size is necessary. Furthermore, as the differences in economic, cultural and linguistic in between the home and host locations can have impact on the creation and the development of a social venture, they should be considered in the future studies. Originality/value This study contributes to the limited literature and studies on social entrepreneurship, specifically, to the context of unstable penurious environment. It also contributes to the literature on bricolage by extending its application from penurious stable environment to the penurious unstable environment. By exploring what and how internal and external resources are utilised to create and develop a socially entrepreneurial venture in a war and conflict zones, this study has added value to the literature on not only bricolage but also entrepreneurship in war and conflict zones

    CICLAD: A Fast and Memory-efficient Closed Itemset Miner for Streams

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    Mining association rules from data streams is a challenging task due to the (typically) limited resources available vs. the large size of the result. Frequent closed itemsets (FCI) enable an efficient first step, yet current FCI stream miners are not optimal on resource consumption, e.g. they store a large number of extra itemsets at an additional cost. In a search for a better storage-efficiency trade-off, we designed Ciclad,an intersection-based sliding-window FCI miner. Leveraging in-depth insights into FCI evolution, it combines minimal storage with quick access. Experimental results indicate Ciclad's memory imprint is much lower and its performances globally better than competitor methods.Comment: KDD2

    Adaptive FEC error control scheme for wireless video transmission

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    Transmission errors have detrimental impact on video quality in wireless network. Hence, this requires highly efficient error correction scheme to significantly improve the quality of the media content. Deploying error correction technique alone would not strategically eradicate the problem unless some adaptation mechanism has been included in order to make efficient decision while adding more redundant information base on the channel condition. Adapting with channel condition can significantly enhance the network performance and video quality as well. In this paper, we paper presents an approach using forward error correction and cross layer mechanism which dynamically adapts with the channel condition to recover the loss packets in order to enhance the perceived video quality. The scheme has been developed and tested on NS-2 simulator and it shows more dramatic improvement in video quality

    Designing Chatbots for Crises: A Case Study Contrasting Potential and Reality

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    Chatbots are becoming ubiquitous technologies, and their popularity and adoption are rapidly spreading. The potential of chatbots in engaging people with digital services is fully recognised. However, the reputation of this technology with regards to usefulness and real impact remains rather questionable. Studies that evaluate how people perceive and utilise chatbots are generally lacking. During the last Kenyan elections, we deployed a chatbot on Facebook Messenger to help people submit reports of violence and misconduct experienced in the polling stations. Even though the chatbot was visited by more than 3,000 times, there was a clear mismatch between the users’ perception of the technology and its design. In this paper, we analyse the user interactions and content generated through this application and discuss the challenges and directions for designing more effective chatbots

    Prevalence of Anemia, Iron Deficiency Anemia and its Socio-Demographic Factors among Pregnant Women in Garmian Province, Kurdistan region of Iraq

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    Anemia is the most common hematologic abnormality in pregnancy. Maternal anemia is associated with adverse fetal, neonatal, and childhood outcomes. This study aims to determine the prevalence of anemia, and iron deficiency anemia (IDA), the severity of the condition, and study the effect of some socio-demographic factors on pregnant women in Garmian province. The study was conducted among 157 pregnant women in Garmian province between 17 and 49 years old. Participants completed a questionnaire that included sociodemographic characteristics, disease, and gestational age. A hematological evaluation, including a complete blood count (CBC) and serum for ferritin testing. Results of this study have shown that the prevalence of anemia and IDA were 34.4% and 15.3%, respectively. Almost three-quarters of the pregnant women had mild anemia, while 31 % of the subjects had moderate anemia, and about 60% of the participants were diagnosed with normocytic anemia. The second trimester had the highest prevalence, with 51.9% for the anemic and 45.8% for IDA subjects, while the first trimester showed the lowest prevalence, with 14.8 % for anemic and 12.5% for IDA subjects. Age, occupation, gravidity with anemia, and iron deficiency anemia did not make a significant difference. Moreover, there was no significant difference in blood indices between anemic and IDA participants. The serum ferritin level was unaffected by the pregnancy trimesters

    Atomically thin boron nitride: a tunnelling barrier for graphene devices

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    We investigate the electronic properties of heterostructures based on ultrathin hexagonal boron nitride (h-BN) crystalline layers sandwiched between two layers of graphene as well as other conducting materials (graphite, gold). The tunnel conductance depends exponentially on the number of h-BN atomic layers, down to a monolayer thickness. Exponential behaviour of I-V characteristics for graphene/BN/graphene and graphite/BN/graphite devices is determined mainly by the changes in the density of states with bias voltage in the electrodes. Conductive atomic force microscopy scans across h-BN terraces of different thickness reveal a high level of uniformity in the tunnel current. Our results demonstrate that atomically thin h-BN acts as a defect-free dielectric with a high breakdown field; it offers great potential for applications in tunnel devices and in field-effect transistors with a high carrier density in the conducting channel.Comment: 7 pages, 5 figure

    Bisphenol A exposure in Mexico City and risk of prematurity: a pilot nested case control study

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    Abstract Background Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. Methods A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. Results BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 μg/L to 6.7 μg/L; uncorrected geometric mean was 1.52 μg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). Conclusions This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks.http://deepblue.lib.umich.edu/bitstream/2027.42/78251/1/1476-069X-9-62.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78251/2/1476-069X-9-62.pdfPeer Reviewe

    Diversity, Dynamics and Therapeutic Application of Clostridioides difficile Bacteriophages

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    Clostridioides difficile causes antibiotic-induced diarrhoea and pseudomembranous colitis in humans and animals. Current conventional treatment relies solely on antibiotics, but C. difficile infection (CDI) cases remain persistently high with concomitant increased recurrence often due to the emergence of antibiotic-resistant strains. Antibiotics used in treatment also induce gut microbial imbalance; therefore, novel therapeutics with improved target specificity are being investigated. Bacteriophages (phages) kill bacteria with precision, hence are alternative therapeutics for the targeted eradication of the pathogen. Here, we review current progress in C. difficile phage research. We discuss tested strategies of isolating C. difficile phages directly, and via enrichment methods from various sample types and through antibiotic induction to mediate prophage release. We also summarise phenotypic phage data that reveal their morphological, genetic diversity, and various ways they impact their host physiology and pathogenicity during infection and lysogeny. Furthermore, we describe the therapeutic development of phages through efficacy testing in different in vitro, ex vivo and in vivo infection models. We also discuss genetic modification of phages to prevent horizontal gene transfer and improve lysis efficacy and formulation to enhance stability and delivery of the phages. The goal of this review is to provide a more in-depth understanding of C. difficile phages and theoretical and practical knowledge on pre-clinical, therapeutic evaluation of the safety and effectiveness of phage therapy for CDI
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