SIR modeling of a disease spread with a detectable and undetectable infectious syndrome

This paper proposes a model for the analysis of an infectious disease spread using a renewed deterministic model of Susceptible-Infected-Recovered (SIR). The SIR is based on compartments or partitions. In this case, the contaminated (infected) class is divided into two sub-compartments: detectable and undetectable. Numerical simulations are carried out to test the obtained theoretical results, and presentations follow graphicall

Constitutive behavior of an AA4032 piston alloy with Cu and Er additions upon high temperature compressive deformation

The Research and Researchers for Industry (RRi); King Mongkut’s University of Technology Thonbur

Strongly coupled binuclear uranium-oxo complexes from uranyl oxo rearrangement and reductive silylation

The most common motif in uranium chemistry is the d0f0 uranyl ion [UO2]21 in which the oxo groups are rigorously linear and inert. Alternative geometries, such as the cis-uranyl, have been identified theoretically and implicated in oxo-atom transfer reactions that are relevant to environmental speciation and nuclear waste remediation. Single electron reduction is now known to impart greater oxo-group reactivity, but with retention of the linear OUO motif, and reactions of the oxo groups to form new covalent bonds remain rare. Here, we describe the synthesis, structure, reactivity and magnetic properties of a binuclear uranium–oxo complex. Formed through a combination of reduction and oxo-silylation and migration from a trans to a cis position, the new butterfly-shaped Si–OUO2UO–Si molecule shows remarkably strong UV–UV coupling and chemical inertness, suggesting that this rearranged uranium oxo motif might exist for other actinide species in the environment, and have relevance to the aggregation of actinide oxide clusters.JRC.E.6-Actinides researc

Chromotographic and wound healing studies of Jatropha curcas (Euphorbiacea)

The wound healing properties of the methanol extract of the leaves of Jatropha curcas were studied by incision and excision wound models in rats. The wound healing effect was compared to that of the standard antibiotic, Cicatrin R. The histopathological profile, phytochemistry and the acute toxicity were also studied. An attempt was made to resolve the extract into its components using thin layer chromatography (TLC). Result of the incision and excision wound model shows significant (P < 0.05) dose-dependent increase in wound contraction rate, skin breaking strength and decrease in epithelization period showing a healing potential comparable to that of Cicatrin powder at a dose of 200 mg/kg. Histopathological studies showed proliferation of epithelial tissue, angiogenesis and fibrosis due to treatment with Jatropha curcas. The prohealing action was due to increased collagen deposition as well as better alignment and maturation. The leaves of Jatropha curcas were found to contain alkaloids, glycosides, saponins, flavonoids, steroids, proteins, tannins, reducing sugars, fats and oils. The intraperitoneal acute toxicity test (LD50) of the extract in mice showed that it  as relatively safe, since at a dose of 5000 mg/kg there was no death. Among chromatographic solvent systems tested, chloroform:ethylacetate (6:4) gave the best resolution of the extract giving the highest number of spots. The present study demonstrates wound healing potential of Jatropha curcasKeywords: wound healing, Jatropha curcas, angiogenesis, epithelization, proliferationJournal of Pharmaceutical and Allied Sciences, Vol. 7 No. 2 (2010

Antibiotic Resistant and Plasmid Borne Bacteria Associated with Locally Produced Honey in Enugu State, Nigeria

Aim: The aim of this study is to isolate and identify bacteria contaminants present in the honey samples sold in Ogbete market and detect the presence of imipenem resistance genes in the isolates. Place and Duration of Study: A total of four samples were collected from Ogbete market at Zenith bank, Peace mass, Wheelbarrow and Peace park stations between the early hours of the morning (8-9am) within the month of April, 2023. Methodology: Microbiological analysis was carried out on the samples, including antimicrobial susceptibility test using disc diffusion method., after which Molecular analysis involving DNA extraction, PCR and Plasmid Profiling, were carried out. Results: The total mean heterotrophic bacterial count ranged from 0.03±2.5×103cfu/ml to 22.1±25.5×103cfu/ml. The highest total mean heterotrophic bacterial count was recorded in Zenith bank while the lowest was in Peace mass. The bacteria isolated and characterized through morphological and biochemical tests include Escherichia coli (45%) Klebsiella spp. (41%), Staphylococcus spp. (9%) and Streptococcus spp. (5%). Escherichia coli had the highest frequency of occurrence at 45% while Streptococcus spp. had the lowest at 5%. The sensitivity test showed that the isolates with the highest frequency of occurrence, Escherichia coli and Klebsiella spp. posed a high resistance to Imipenem and Nalidixic at 80% while the least resistance was in Levofloxacin at 10% from these two isolates. The gene of interest, BlaIMP was found after PCR assay. Plasmid DNA was further carried out using the alkaline lysis method using the Zymo research kit. All isolates possessed a single plasmid with molecular weight of 23.1kbp. Conclusion: These isolates may undergo horizontal gene transfer and confer resistance to other microorganisms. Thus, there is need for the development of proper measures to counter bacterial contamination of locally produced honey as this poses a threat to public health

Assessment of Radiation Dose Level in Farm Soils of Mission Quarters, Wukari, Taraba State, Nigerian

The study has assessed the amount of radiation exposed to farm soils in mission quarters Wukari, Taraba State. Assessment of radiation dose level is very important, especially in soil since man depends on Soil for his food. Assessment of radiation will help to know the radiation dose in the soil.&nbsp; The objective of this work is to determine radiation dose in soils and to provide necessary information of human health risks associated with radioactivity in soil and its effects on plant materials as well as human being. Different soil samples were collected and the Radiation Alert Inspector EXP, was used to measure the level of radiation exposure in the soil samples. The results showed low amount of radiation dose level. The average dose values ranging between 0.035±0.097 to 0.333±0.289, an absorbed dose rate ranging between 3.50 x 10-8±0.097 to 3.33 x 10-7±0.289 and annual dose rate ranging between 0.059±0.097 to 0.758±0.289. These results revealed that the dose rates do not exceed the recommended values by International Commission on Radiological Protection (ICRP) is 1mSvyr1 for the general public. It is less and in compliance with the recommended radiation dose level. Therefore do not pose a significant health hazard. The radiation dose level has no negative effect on both the plants and the dwellers. Therefore the study area is safe for human activities.&nbsp

Instrumental Neutron Activation Analysis (INAA) As-sessment of REE of Soil from Mining Site Umuahia, Abia State, South East, Nigeria

In this work, the main goal was to examine the REE concentration and distribution pattern in soil from Umuahia, Abia State, Southeast, Nigeria, in a clay mining site compared with a non-contaminated site approximately 3 km away. The REE were determined by Instrumental Neutron Activation Analysis (INAA) at IPEN, Brazil. The main mineralogy of the samples was determined by XRD. The following REE were determined: Ce, Eu, La, Lu, Nd, Sm, Tb and Yb. Soil samples from the mining area present quartz and kaolinite as their main constituents, with REE concentrations comparable with that of the Upper Continental Crust and the North American Shale Composite. The calculated Geoaccumulation index (IGeo) indicate that REE have natural origin and ∑LREEN/∑HREEN ratio show an enrichment of the light over heavy REE, in samples of the clay mining area

Probing the mechanism of CO2 capture in diamine-appended metal-organic frameworks using measured and simulated X-ray spectroscopy.

International audienceDiamine-appended metal-organic frameworks display great promise for carbon capture applications, due to unusual step-shaped adsorption behavior that was recently attributed to a cooperative mechanism in which the adsorbed CO2 molecules insert into the metal-nitrogen bonds to form ordered ammonium carbamate chains [McDonald et al., Nature, 2015, 519, 303]. We present a detailed study of this mechanism by in situ X-ray absorption spectroscopy and density functional theory calculations. Distinct spectral changes at the N and O K-edges are apparent upon CO2 adsorption in both mmen-mg(2)(dobpdc) and mmen-Mn-2(dobpdc), and these are evaluated based upon computed spectra from three potential adsorption structures. The computations reveal that the observed spectral changes arise from specific electronic states that are signatures of a quasi-trigonal planar carbamate species that is hydrogen bonded to an ammonium cation. This eliminates two of the three structures studied, and confirms the insertion mechanism. We note the particular sensitivity of X-ray absorption spectra to the insertion step of this mechanism, underpinning the strength of the technique for examining subtle chemical changes upon gas adsorption