22 research outputs found
The non-zero divisor graph of ring of integers modulo six and the hamiltonian quaternion over integers modulo two
The study of graph theory was introduced and widely researched since many practical problems can be represented by graphs. A non-zero divisor graph is a graph in which its set of vertices is the non-zero elements of the ring and the vertices x and y are adjacent if and only if xy ≠ 0. In this study, we introduced the non-zero divisor graphs of some finite commutative rings in specific the ring of in tegers modulo 6, 6 and ring of Hamiltonian quaternion, (2). First, the non-zero divisors of the commutative rings are found. Then, the non-zero divisor graphs are constructed. Finally, some properties of the graph, including the chromatic number, clique number, girth and the diameter are obtained
Characterisation of colistin resistance in Gram-negative microbiota of pregnant women and neonates in Nigeria
A mobile colistin resistance gene mcr was first reported in 2016 in China and has since been found with increasing prevalence across South-East Asia. Here we survey the presence of mcr genes in 4907 rectal swabs from mothers and neonates from three hospital sites across Nigeria; a country with limited availability or history of colistin use clinically. Forty mother and seven neonatal swabs carried mcr genes in a range of bacterial species: 46 Enterobacter spp. and single isolates of; Shigella, E. coli and Klebsiella quasipneumoniae. Ninety percent of the genes were mcr-10 (n = 45) we also found mcr-1 (n = 3) and mcr-9 (n = 1). While the prevalence during this collection (2015-2016) was low, the widespread diversity of mcr-gene type and range of bacterial species in this sentinel population sampling is concerning. It suggests that agricultural colistin use was likely encouraging sustainment of mcr-positive isolates in the community and implementation of medical colistin use will rapidly select and expand resistant isolates
Effects of antibiotic resistance, drug target attainment, bacterial pathogenicity and virulence, and antibiotic access and affordability on outcomes in neonatal sepsis: an international microbiology and drug evaluation prospective substudy (BARNARDS)
Background
Sepsis is a major contributor to neonatal mortality, particularly in low-income and middle-income countries (LMICs). WHO advocates ampicillin–gentamicin as first-line therapy for the management of neonatal sepsis. In the BARNARDS observational cohort study of neonatal sepsis and antimicrobial resistance in LMICs, common sepsis pathogens were characterised via whole genome sequencing (WGS) and antimicrobial resistance profiles. In this substudy of BARNARDS, we aimed to assess the use and efficacy of empirical antibiotic therapies commonly used in LMICs for neonatal sepsis.
Methods
In BARNARDS, consenting mother–neonates aged 0–60 days dyads were enrolled on delivery or neonatal presentation with suspected sepsis at 12 BARNARDS clinical sites in Bangladesh, Ethiopia, India, Pakistan, Nigeria, Rwanda, and South Africa. Stillborn babies were excluded from the study. Blood samples were collected from neonates presenting with clinical signs of sepsis, and WGS and minimum inhibitory concentrations for antibiotic treatment were determined for bacterial isolates from culture-confirmed sepsis. Neonatal outcome data were collected following enrolment until 60 days of life. Antibiotic usage and neonatal outcome data were assessed. Survival analyses were adjusted to take into account potential clinical confounding variables related to the birth and pathogen. Additionally, resistance profiles, pharmacokinetic–pharmacodynamic probability of target attainment, and frequency of resistance (ie, resistance defined by in-vitro growth of isolates when challenged by antibiotics) were assessed. Questionnaires on health structures and antibiotic costs evaluated accessibility and affordability.
Findings
Between Nov 12, 2015, and Feb 1, 2018, 36 285 neonates were enrolled into the main BARNARDS study, of whom 9874 had clinically diagnosed sepsis and 5749 had available antibiotic data. The four most commonly prescribed antibiotic combinations given to 4451 neonates (77·42%) of 5749 were ampicillin–gentamicin, ceftazidime–amikacin, piperacillin–tazobactam–amikacin, and amoxicillin clavulanate–amikacin. This dataset assessed 476 prescriptions for 442 neonates treated with one of these antibiotic combinations with WGS data (all BARNARDS countries were represented in this subset except India). Multiple pathogens were isolated, totalling 457 isolates. Reported mortality was lower for neonates treated with ceftazidime–amikacin than for neonates treated with ampicillin–gentamicin (hazard ratio [adjusted for clinical variables considered potential confounders to outcomes] 0·32, 95% CI 0·14–0·72; p=0·0060). Of 390 Gram-negative isolates, 379 (97·2%) were resistant to ampicillin and 274 (70·3%) were resistant to gentamicin. Susceptibility of Gram-negative isolates to at least one antibiotic in a treatment combination was noted in 111 (28·5%) to ampicillin–gentamicin; 286 (73·3%) to amoxicillin clavulanate–amikacin; 301 (77·2%) to ceftazidime–amikacin; and 312 (80·0%) to piperacillin–tazobactam–amikacin. A probability of target attainment of 80% or more was noted in 26 neonates (33·7% [SD 0·59]) of 78 with ampicillin–gentamicin; 15 (68·0% [3·84]) of 27 with amoxicillin clavulanate–amikacin; 93 (92·7% [0·24]) of 109 with ceftazidime–amikacin; and 70 (85·3% [0·47]) of 76 with piperacillin–tazobactam–amikacin. However, antibiotic and country effects could not be distinguished. Frequency of resistance was recorded most frequently with fosfomycin (in 78 isolates [68·4%] of 114), followed by colistin (55 isolates [57·3%] of 96), and gentamicin (62 isolates [53·0%] of 117). Sites in six of the seven countries (excluding South Africa) stated that the cost of antibiotics would influence treatment of neonatal sepsis
A Resource Performance Model for Efficient Distribution of Resources to Operating System Services in Factored Operating System
Central processing will be composed of thousands of heterogeneous cores in the near future. The existing systems are difficult to scale, adapt or tackle the heterogeneous nature of the future multicore technology. This study developed a resource performance model for efficient distribution of resources to Operating System (OS) services. A Multi-Agent based method was used to design the architecture of the model while the Unified Modeling Language and flowchart were used in the detailed design of the proposed model. The model was simulated using Java 2 Enterprise Edition. In simulating the model, four (4) variables were used to determine the processor core capacity. The result of the simulation shows an efficient distribution of 5000 cores to four (4) OS services (servers) with each having 1250 fleet of servers. The percentage differences in the four of servers from the minimum are 0.11%, 0.09% and 0.04% respectively. The result shows that the distribution of processor cores to OS services is efficient since the differences in total performance function of the fleets of servers were very little. Therefore, to maximize the profit that comes with multicore systems, this efficient model is needed for processor cores distribution to OS service in a Factored Operating System.
 
Response of Domestic Pigeons (Columba livia) to Experimental Infection with Chicken Isolate of Infectious Bursal Disease (IBD) Virus
The susceptibility of pigeons (Columba livia) to chicken isolate of infectious bursal disease (IBD) virus was investigated under arid zone condition. Thirty pigeons, 15 adults and 15 young ones were acquired from the Maiduguri Monday Market and some
households in Maiduguri. The pigeons were divided into two groups thus: Group A, which is the experimental group and consisted of ten (10) adults and ten (10) young pigeons. Group B that served as the control group was made up of five (5) adults and five (5) young pigeons. Pigeons in group A were infected with 3 drops of IBD virus inoculum orally while those in group B were given same quantity of normal saline per os. All the pigeons in groups A and B did not manifest any clinical sign throughout the period of the study. However, some of the serum samples from the infected group were positive for presence of
precipitin antibody on day 7 and 14 PI, while all the samples became negative on 21 days PI. The study revealed that pigeons (young and adults) are resistant to experimental infection with chicken isolate of IBD virus. However, the birds seroconverted following exposure to the virus despite the absence of clinical signs. This showed that there was “virus take” following exposure of the species to IBD virus. The possible role of pigeons in the epidemiology of IBD in Nigeria need to be further investigated. Keywords: Domestic pigeon, experimental infection, IBD virusSahel Journal of Veterinary Sciences Vol. 5 (1) 2006 pp. 59-6
Antibacterial efficacy of ethyl acetate fraction of Psidium guajava leaf aqueous extract on experimental Escherichia coli (O78) infection in chickens
Aim: This study was desingned to examine the efficacy of ethyl acetate fraction of aqueous extracted Psidium guajava leaves on chicks experimentally-infected with diarrheagenic strain of Escherichia coli O78.
Methods: A total of 60 ISA brown male chicks were randomly divided into 6 Groups of ten chicks each in separate cages. Group A was not infected and not treated. Groups B, C and D were infected and treated with extracts at a dose of 25, 50 and 100 mg/kg respectively for 10 days. Group E was infected and treated with oxytetracycline while Group F was infected, but left untreated. Chicks from all groups were closely monitored for clinical signs, body weight change and fecal bacterial shedding load during the course of the experiment.
Results: Diarrhea, vents pasted with feces, drop in feed intake accompanied by slow weight gain and decreased activity was observed in infected untreated groups. Groups treated with graded doses of the extract experienced a dose-dependent decreased in severity of the clinical signs shown compared to the infected untreated group. Bacterial shedding load was found to be lower in groups treated with the extract and oxytetracycline than those without intervention.
Conclusion: Ethyl acetate soluble fraction of leaf extract of Psidium guajava effectively controlled diarrhea and decreased the severity of other clinical signs caused by experimental E. coli infections in chicks
The perfect codes of commuting zero divisor graph of some matrices of dimension two
The study of graph properties has gathered many attentions in the past years. The graph properties that are commonly studied include the chromatic number, the clique number and the domination number of a finite graph. In this study, a type of graph properties, which is the perfect code is studied. The perfect code is originally used in coding theory, then extended to other fields including graph theory. Hence, in this paper, the perfect code is determined for the commuting zero divisor graphs of some finite rings of matrices. First, the commuting zero divisor graph of the finite rings of matrices is constructed where its vertices are all zero divisors of the ring and two distinct vertices, say x and y, are adjacent if and only if xy = yx = 0. Then, from the vertex set of the graph, the neighborhood elements of the vertices are determined in order to compute the perfect codes of the graph
Antibody profile following vaccination with thermostable (ND-I2) vaccine in village chicken that survived the Newcastle disease outbreak
The antibody profile of village chickens that recovered from clinical Newcastle disease infection were monitored following vaccination with thermostable (NDI2-HR) vaccine over a period of 5 weeks. The birds were grouped into two: vaccinated and non-vaccinated. Antibody profile was determined using haemagglutination inhibition (HI) test. Seromonitoring result revealed a significant (p<0.05) seroconversion with rise in Geometric antibody titer (GMT) values of antibody among the vaccinated birds that survived the outbreak, with peaked at week two following vaccination and declined subsequently in both study groups. No significant difference was observed in the antibody profile of vaccinated and non-vaccinated group which is an indication of low response to vaccination. Vaccination of surviving birds following ND outbreak may be of little value in development of immunity to the disease
Natural outbreak of Newcastle disease in village chickens obtained from various sources in semi-arid region of Nigeria
An outbreak of Newcastle Diseases (ND) was investigated in caged local chickens that were obtained from various locations in and around Bama, Nigeria. A morbidity rate of 58% and morality rate of 60% were recorded among the affected birds. The birds started dying two days after the onset of clinical signs. The signs observed were consistent with ND and included respiratory distress with gasping and sometimes coughing; nervous signs such as paralysis, torticollis; loss of appetite, swollen head and wattles, sometimes ocular and nasal discharge, severe conjunctives and death after some days. The death peaked on day 5 following onset of clinical signs and ceased on day 13 after the onset. The histopathological lesions observed include congestion of the spleen, kidney and lungs, hemorrhages in the proventriculus and kidney. Majority 20/26 (76.9%) of the sera tested during the acute phase of the disease were negative of ND antibodies while those collected during the convalescent phase of the disease showed varying titres ranging between 1:20 and 1:80, suggested of a recent viral infection. All tissue samples collected from infected birds were positive for Newcastle disease virus haemagglutinating antigens and titers ranging between 1:2 and 1:6 were recorded. It was concluded that the outbreak might have been as a result of introduction of some in apparently infected chicken into the cage. It was recommended that the birds should be screened for the presence of ND virus before introduce into a new flock in addition village chicken should be obtained from source that are not infected with the virus and village chicken should be vaccinated routinely against ND