296 research outputs found

    Evolution Of Special Ruled Surfaces Via The Evolution Of Their Directrices In Euclidean 3-Space E3

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    In this paper, evolutions of ruled surfaces that are generated by the normal and binormal vector fields of space curve (normal and binormal surfaces) are presented. These evolutions of the ruled surfaces depend on the evolutions of their directrices. Geometric visualization of these ruled surfaces are presented. In addition, the conditions which make these surfaces of types inextensible, developable and minimal are obtained

    THE PROTECTIVE ROLE OF OMEGA-3 AGAINST GENOTOXICITY AND REPRODUCTIVE TOXICITY OF COBALT OXIDE NANOPARTICLES ACUTE TREATMENT IN MALE MICE

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    Objective: Cobalt nanoparticles (NPs), especially cobalt oxide NPs (Co3O4 NPs) are attracting unique shaped NPs that are used in different biomedical applications and medicine. Different in vitro studies report their toxic and carcinogenic effect but limited in vivo studies were present on its genotoxic potential. The present study was aimed to evaluate the genotoxic potential of Co3O4 NPs on bone marrow cells and sperms and the protective role of omega-3 in male albino mice.Methods: Animals were segregated into four groups that were orally treated for 3 consecutive days, Group 1: Negative control; Group 2: Omega-3 (250 mg/kg); Group 3: Co3O4 NPs (20 mg/kg); and Group 4: Combined group (250 mg/kg Omega-3 and Co3O4 NPs 20 mg/kg).Results: The present results show that Co3O4 NPs administration significantly increased number of micronucleated polychromatic erythrocytes (PCEs)/1000 PCEs, sperm abnormalities, and DNA damage, significantly decreased sperm motility and concentration in comparison to negative control group. However, Omega-3 administration in the combined group modulates the genotoxic potential of Co3O4 NPs in comparison to Co3O4 NPs group.Conclusion: The present study reports the genotoxic potential of Co3O4 NPs in vivo and assesses the protective role of Omega-3 administration due to its antioxidant effect

    Development of hand-arm model rig for tremor excitation

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    This paper describes the development of a handarm model rig to simulate human tremor behaviour. The experimental rig is designed as an apparatus to induce vibration along a hand-arm model. An Intra Vernacular (IV) Training arm is used as the handarm model. Displacement and acceleration behaviour at three selected points along the handarm model were recorded by mean of piezoelectric accelerometer. The data from the experiment can be used for further analysis of the human hand-arm tremor especially for Parkinson's disease (PD) patients. Results from the experiments are raw data which can later be used in designing an appropriate instrument that can suppress the hand tremor

    Impurity effects on the melting of Ni clusters

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    We demonstrate that the addition of a single carbon impurity leads to significant changes in the thermodynamic properties of Ni clusters consisting of more than a hundred atoms. The magnitude of the change induced is dependent upon the parameters of the Ni-C interaction. Hence, thermodynamic properties of Ni clusters can be effectively tuned by the addition of an impurity of a particular type. We also show that the presence of a carbon impurity considerably changes the mobility and diffusion of atoms in the Ni cluster at temperatures close to its melting point. The calculated diffusion coefficients of the carbon impurity in the Ni cluster can be used for a reliable estimate of the growth rate of carbon nanotubes.Comment: 27 pages, 13 figure

    Bi-allelic GAD1 variants cause a neonatal onset syndromic developmental and epileptic encephalopathy.

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    Developmental and epileptic encephalopathies are a heterogeneous group of early-onset epilepsy syndromes dramatically impairing neurodevelopment. Modern genomic technologies have revealed a number of monogenic origins and opened the door to therapeutic hopes. Here we describe a new syndromic developmental and epileptic encephalopathy caused by bi-allelic loss-of-function variants in GAD1, as presented by 11 patients from six independent consanguineous families. Seizure onset occurred in the first 2 months of life in all patients. All 10 patients, from whom early disease history was available, presented with seizure onset in the first month of life, mainly consisting of epileptic spasms or myoclonic seizures. Early EEG showed suppression-burst or pattern of burst attenuation or hypsarrhythmia if only recorded in the post-neonatal period. Eight patients had joint contractures and/or pes equinovarus. Seven patients presented a cleft palate and two also had an omphalocele, reproducing the phenotype of the knockout Gad1-/- mouse model. Four patients died before 4 years of age. GAD1 encodes the glutamate decarboxylase enzyme GAD67, a critical actor of the Îł-aminobutyric acid (GABA) metabolism as it catalyses the decarboxylation of glutamic acid to form GABA. Our findings evoke a novel syndrome related to GAD67 deficiency, characterized by the unique association of developmental and epileptic encephalopathies, cleft palate, joint contractures and/or omphalocele

    Positional cloning of the barley tillering gene uniculme4

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    Manipulation of plant architectural traits such as the number of tillers can effectively increase grain yield in cereals. Within the frame of the TriticeaeGenome project (www.triticeaegenome.eu), the objective of our group was the fine mapping and positional cloning of uniculme4 (cul4), a gene required for tillering in barley. Based on initial medium resolution mapping of the locus, a segregating population including 4900 F3 plants was developed and genotyped with three tightly linked SNP markers (Tavakol et al., abstract P321, PAG XIX). The locus was further resolved through mapping of 8 synteny-derived markers allowing the identification of a candidate gene that co-segregates with the cul4 phenotype. The two genes that flank the candidate gene in Brachypodium and rice were positioned 0.11 cM and 0.12 cM from cul4, respectively: development of new markers is underway using sequence information from two BACs anchored to the physical map and spanning this region. The intron-exon structure of the candidate gene was determined from a cDNA isolated from wild-type plants. Resequencing of independent cul4 stocks identified three distinct mutations within the candidate gene, including a deletion of the 5\u2019 region. Comparison of expression levels and patterns in mutant and wild-type plants is underway

    Stop Turning a Blind Eye: Tobacco Smoking Among Egyptian Patients With Schizophrenia

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    Background: Patients with schizophrenia have considerably higher rates of mortality than general population. Multiple factors may play a role in this. Despite being a major preventable cause of death, smoking is usually overlooked when dealing with patients with schizophrenia. Understanding the pattern of smoking, its severity, and the reasons to quit might be helpful in managing patients with schizophrenia and decreasing the mortality gap.Subjects and Methods: The study included smokers divided into two groups; the first included 346 patients with schizophrenia while the second group had 150 smokers with no mental illness. Both groups were assessed and compared regarding sociodemographic variables, pattern of smoking, severity of nicotine dependence, and motivation to quit smoking.Results: Earlier age of starting to smoke, higher number of cigarettes per day, and lower dependency scores were noted in patients with Schizophrenia. Positive correlation was found between positive symptoms and severity of dependence. Specific positive symptoms were correlated to number of cigarettes per day and time before first cigarette. Patients with Schizophrenia showed a significant difference in intrinsic reasons to quit (health concerns and self-control), which were also positively correlated to their positive symptoms score. Linear regression analysis for predictors of FTND score revealed that only age, sex, and schizophrenia were significant predictors of FTND score.Conclusion: Patients with schizophrenia smoke at earlier ages and smoke more cigarettes per day, yet, have less severe dependence than non-schizophrenic counterparts. Positive symptoms play a role in their smoking pattern and severity. Health concerns and self-control are their main motives to quit smoking

    Analysis of energy and exergy for the flat plate solar air collector with longitudinal fins embedded in paraffin wax located in baghdad center

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    Latent heat of the fusion for the Phase changeable materials (PCM) can be utilized as heat energy store, and this energy can be employed in different applications. In present experimental work, effect of using the embedded longitudinal fins within the paraffin wax, on the energy and exergy performance for the solar air collector was investigated under the Baghdad governorate climate. Compared with the collector without paraffin wax, the results indicated that using of paraffin wax as a thermal storage material reduces the losses of energy and exergy of the collector, high levels of heat reduction by using PCM/Fins were about 33 and 40% respectively at the peak heat charging time (12:30 PM), while the decreasing in energy and exergy losses of the collector with PCM only was about 24 and 30% respectively at the same time of charging (12:30 PM). Due to the going of sum heat to store in the paraffin wax at the charging heat time, the energy along with exergy heat gains, while efficiencies were decreased with and without fins, this decreasing in the heat was the most by using PCM/Fins and it was around 30 and 44%, respectively for energy and exergy efficiencies, while it was about 20 and 31% by using PCM only at the same time of testing. The benefit of using embedded longitudinal fins in PCM is to enhance the thermal storage efficiency by about 6% compared with the solar collector that uses PCM only

    Epidemiology of Coxiella burnetii infection in Africa: a OneHealth systematic review

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    Background: Q fever is a common cause of febrile illness and community-acquired pneumonia in resource-limited settings. Coxiella burnetii, the causative pathogen, is transmitted among varied host species, but the epidemiology of the organism in Africa is poorly understood. We conducted a systematic review of C. burnetii epidemiology in Africa from a “One Health” perspective to synthesize the published data and identify knowledge gaps.<p></p> Methods/Principal Findings: We searched nine databases to identify articles relevant to four key aspects of C. burnetii epidemiology in human and animal populations in Africa: infection prevalence; disease incidence; transmission risk factors; and infection control efforts. We identified 929 unique articles, 100 of which remained after full-text review. Of these, 41 articles describing 51 studies qualified for data extraction. Animal seroprevalence studies revealed infection by C. burnetii (≤13%) among cattle except for studies in Western and Middle Africa (18–55%). Small ruminant seroprevalence ranged from 11–33%. Human seroprevalence was <8% with the exception of studies among children and in Egypt (10–32%). Close contact with camels and rural residence were associated with increased seropositivity among humans. C. burnetii infection has been associated with livestock abortion. In human cohort studies, Q fever accounted for 2–9% of febrile illness hospitalizations and 1–3% of infective endocarditis cases. We found no studies of disease incidence estimates or disease control efforts.<p></p> Conclusions/Significance: C. burnetii infection is detected in humans and in a wide range of animal species across Africa, but seroprevalence varies widely by species and location. Risk factors underlying this variability are poorly understood as is the role of C. burnetii in livestock abortion. Q fever consistently accounts for a notable proportion of undifferentiated human febrile illness and infective endocarditis in cohort studies, but incidence estimates are lacking. C. burnetii presents a real yet underappreciated threat to human and animal health throughout Africa.<p></p&gt
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