Correlation between the nuclear structure and reaction dynamics of Ar-isotopes as projectile using the relativistic mean-field approach

This theoretical study is devoted to bridging the gap between the nuclear structure and reaction dynamics and unravelling their impact on each other, considering the neutron-rich light mass 30-60Ar isotopes. Using the relativistic mean-field with the NL3* parameter set, several bulk properties such as binding energies, charge radii, quadrupole deformation parameter, two neutron separation energy, and differential two neutron separation energy with the shell closure parameter are probed for the mentioned isotopic chain. For validation, the RMF (NL3*) results are compared with those obtained from the finite range droplet model (FRDM), Weizsacker-Skyrme model with WS3, WS* parameters and the available experimental data. Most of the participating isotopes are found to be prolate in structure and neutron shell closures are conspicuously revealed at N=14, 20, 40 but weakly shown at N=24, 28, 34. From our analysis, a central depletion in the nucleonic density is identified in 32Ar and 42-58Ar, indicating them as possible candidates for a semi-bubble-like structure. Interestingly, these results are consistent with recent theoretical and experimentally measured data. Besides, using the Glauber model, the reaction cross-sections are determined by taking 26-48Ar as projectiles and stable targets such as 12C, 16O, 40Ca, 90Zr, 124,132Sn, 208Pb and 304120. Although there is no experimental evidence for the stability of 304120, it has been predicted in Ref. [Mod. Phys. Lett. A {\bf 27}, 1250173 (2012)] as a stable nucleus. A relatively higher cross-section value is noticed between 30Ar and 32Ar which infers that 32Ar is the most stable isotope among the considered chain. Moreover, we noticed that the profile of the differential cross-sections and scattering angle are highly influenced by the mass of the target nuclei and the magnitude of the incident energy of the projectile nucleus.Comment: 19 pages, 7 figure

Preformation Probability and Kinematics of Clusters Emission yielding Pb-daughters

In the present study, the newly established preformation formula is applied for the first time to study the kinematics of the cluster emission from various radioactive nuclei, especially those decaying to the double-shell closure $^{208}$Pb nucleus and its neighbours as daughters. The recently proposed universal cluster preformation formula has been established based on the concepts that underscore the influence of the mass and charge asymmetry ($\eta_A$ and $\eta_Z$), cluster mass $A_c$ and the Q-value, paving the way to quantify the energy contribution during the preformation as well as the tunnelling process separately. The cluster-daughter interaction potential is obtained by folding the relativistic mean-field (RMF) densities with the recently developed microscopic R3Y using the NL$3^*$ and the phenomenological M3Y NN potentials to compare their adaptability. The penetration probabilities are calculated from the WKB approximation. With the inclusion of the new preformation probability $P_0$, the predicted half-lives from the R3Y and M3Y interactions are in good agreement with the experimental data. Furthermore, a careful inspection reflects slight differences in the decay half-lives, which arise from their respective barrier properties. The $P_0$ for the systems with the double magic shell closure $^{208}$Pb daughter are found to be relatively higher with an order of $\approx 10^2$ than those with neighbouring Pb-daughter nuclei. By exploring the contributions of the decay energy, the recoil effect of the daughter nucleus is appraised, unlike several other conjectures. Thus, the centrality of the Q-value in the decay process is demonstrated and re-defined within the preformed cluster-decay model. Besides, we have introduced a simple and intuitive set of criteria that governs the estimation of recoil energy in the cluster radioactivity.Comment: 09 Pages, 06 Figures, and 01 Tabl

Prevalence and Characterization of Salmonella Isolates from Poultry Farms in Ilorin, Nigeria

Poultry birds are very important source of essential proteins in developing countries, but also play an important role in transmission of Salmonella to human and nonhuman. Exposure to this pathogen also occurs through use of poultry droppings as manure for crop and vegetable production. This study investigated prevalence of Salmonella in feces of poultry farms in Ilorin, Nigeria. Salmonella isolated were further characterized by molecular method. Fecal samples were cultured in pre-enrichment medium, Selenite F medium and finally sub-cultured on Salmonella-Shigella agar. None lactose fermenting colonies with black center were picked for presumptive identification using biochemical tests and confirmed by serological test by method previously described. Molecular characterization was carried out using 16S rRNA gene sequencing following standard procedure. Out of 170 samples collected and examined, 8 (4.7%) gave biochemical characteristics that resembled Salmonella, but only 6 (3.5%) were confirmed as Salmonella by polyvalent antisera. Molecular characterization revealed that serovars isolated were Salmonella Enteritidis 3 (1.8%) and Salmonella Paratyphi 3 (1.8%). Phylogenetic tree constructed by neighbor-joining method as derived from analysis of the 16S rRNA gene sequences showed close relationship to Salmonella Paratyphi strain FB0015 16S ribosoma RNA gene partial sequence to our Salmonella Paratyphi isolates. The detection of 3.5% prevalence rate of Salmonella serovar from feces of laying poultry birds my serve as potential source of transmission of this pathogen to human through chicken meat, egg or use of poultry dropping as manure in crop or vegetable production

Capital assets: a community research intervention by the African Forum in Redbridge and Watham Forest

Duration: September 1999 - November 2000 This was a community-led initiative in which over 1000 Africans resident in Redbridge and Waltham Forest were asked about their assets and health needs. The survey was instigated by Redbridge & Waltham Forest African Forum, and undertaken by community groups themselves in collaboration with Sigma Research. The survey was designed both to gather information from the communities and to provide information to them. The information sought was not simply about the participants needs but also about the assets within those communities to address those needs. The project sought information about the relationship between Africans living in Redbridge or Waltham Forest, their assets, health needs and the potential for interventions. It did so by: providing all stakeholders with clear and accessible information about the demography of the local African communities. mapping the priorities and needs of the groups. assessing knowledge about HIV and its prevention. mapping linguistic assets and social structures of participating community groups that may contribute to meeting these needs. identifying acceptable, culturally appropriate methods of intervention. Questionnaire content was led by the members of the African Forum as was the structure and content of the report. Members of community groups did all the interviewing. Between them, 41 interviewers talked to 1008 residents. The majority of African women and men living locally were at an age when people can be at their most active physically, mentally and economically. Mental health and HIV and AIDS were the major health concerns although health concerns were associated with country of birth. Many respondents lacked basic knowledge of HIV transmission. There is a need for more awareness of clinical sexual health services. Language ability and social networks are common assets for health. English is spoken by 78% of participants and 88% of the entire sample mentioned at least one person they were close to. The survey provides information that helps to identify key areas where community organisations and statutory services working in partnership can improve quality of life and access to services. The final report was called Capital assets: a community research intervention by The African Forum in Redbridge and Waltham Forest

A longitudinal survey of African animal trypanosomiasis in domestic cattle on the Jos Plateau, Nigeria:prevalence, distribution and risk factors

BACKGROUND: Trypanosomiasis is a widespread disease of livestock in Nigeria and a major constraint to the rural economy. The Jos Plateau, Nigeria was free from tsetse flies and the trypanosomes they transmit due to its high altitude and the absence of animal trypanosomiasis attracted large numbers of cattle-keeping pastoralists to inhabit the plateau. The Jos Plateau now plays a significant role in the national cattle industry, accommodating approximately 7% of the national herd and supporting 300,000 pastoralists and over one million cattle. However, during the past two decades tsetse flies have invaded the Jos Plateau and animal trypanosomiasis has become a significant problem for livestock keepers. METHODS: In 2008 a longitudinal two-stage cluster survey on the Jos Plateau. Cattle were sampled in the dry, early wet and late wet seasons. Parasite identification was undertaken using species-specific polymerase chain reactions to determine the prevalence and distribution bovine trypanosomiasis. Logistic regression was performed to determine risk factors for disease. RESULTS: The prevalence of bovine trypanosomiasis (Trypanosoma brucei brucei, Trypanosoma congolense savannah, Trypanosoma vivax) across the Jos Plateau was found to be high at 46.8% (39.0 – 54.5%) and significant, seasonal variation was observed between the dry season and the end of the wet season. T. b. brucei was observed at a prevalence of 3.2% (1% – 5.5%); T. congolense at 27.7% (21.8% - 33.6%) and T. vivax at 26.7% (18.2% - 35.3%). High individual variation was observed in trypanosomiasis prevalence between individual villages on the Plateau, ranging from 8.8% to 95.6%. Altitude was found to be a significant risk factor for trypanosomiasis whilst migration also influenced risk for animal trypanosomiasis. CONCLUSIONS: Trypanosomiasis is now endemic on the Jos Plateau showing high prevalence in cattle and is influenced by seasonality, altitude and migration practices. Attempts to successfully control animal trypanosomiasis on the Plateau will need to take into account the large variability in trypanosomiasis infection rates between villages, the influence of land use, and husbandry and management practices of the pastoralists, all of which affect the epidemiology of the disease

Shifting livelihood strategies in northern Nigeria - extensified production and livelihood diversification amongst Fulani pastoralists

Abstract This paper presents an in-depth investigation of the livelihood strategies of Fulani pastoralists in north central Nigeria. Results show a diversified crop-livestock system aimed at spreading risk and reducing cattle offtake, adapted to natural resource competition and insecurity by extensification, with further diversification into off-farm activities to spread risk, increase livelihood security and capture opportunities. However, significant costs were associated with extensification, and integration of crop and livestock enterprises was limited. Mean total income per capita in the study area was $554 or$1.52/person/day with 42% of households earning less than 1.25/person/day. Income levels were positively correlated with income diversity and price received per animal sold, rather than herd size. The outcomes of this livelihood strategy were favourable across the whole community, but when individual households are considered, there was evidence of moderate economic inequality in total income, cash income and herd size (Gini coefficient 0.32, 0.35 and 0.43 respectively). The poorest households were quite vulnerable, with low assets, income and income diversity. Implications for sustainability are discussed given the likelihood that the negative trends of reduced access to natural resources and insecurity will continue

Diarrhoeagenic E. coli occurrence and antimicrobial resistance of Extended Spectrum Beta-Lactamases isolated from diarrhoea patients attending health facilities in Accra, Ghana.

IntroductionDiarrhoea accounts for high morbidity and mortality in children and adults worldwide. Extended Spectrum Beta-Lactamase-Producing Enterobacteriaceae (ESBL-PE) and Diarrhoeagenic Escherichia coli (DEC) contribute to prolonged hospitalization because of their resistance and virulence properties aiding in the spread of diarrhoeal disease and delayed treatment.AimTo determine DEC and the antimicrobial resistance of ESBL-PE isolated among diarrhoea patients attending two health facilities in Ghana.MethodsStool samples were collected from 122 diarrhoeal patients who attended Maamobi General Hospital and Kaneshie Polyclinic between January 2019 and March 2020. Identification of bacteria was performed by using the Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Using disk diffusion, antimicrobial susceptibility testing (AST) was conducted and interpreted according to the 2018 CLSI guidelines. Detection of ESBL and DEC genes was performed using Polymerase chain reaction (PCR).ResultsA total of 80.3% (98/122) Enterobacteriaceae was recovered from the patients in the study with an overall ESBL occurrence of 20.4% (20/98), predominantly among E. coli showed 13.2% (10/76), Klebsiella pneumoniae,35.7%(5/14) and Proteus mirabilis, 57.1%(4/7). Among the ESBL genes detected, blaTEM (n = 14) was common, followed by blaCTX-M (n = 13) and blaSHV (n = 4). Thirty-four E. coli isolates possessed the heat labile (Lt) gene of Enterotoxigenic E. coli (ETEC).ConclusionOur findings confirm the existence of DEC and the antimicrobial resistance patterns of ESBL-PE among stool isolates, limiting the options of commonly used drugs for diarrhoeal treatment in Ghana. Routine laboratory testing in health care facilities and strengthened surveillance systems among hospital networks are encouraged for a better understanding of their epidemiology and clinical implications