337 research outputs found

    Coral reef and associated habitat mapping using ALOS satellite imagery

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    Coral reefs are rich in biodiversity and ecosystem services. However increase in degradation are still occurring at an alarming rate. In management of this ecosystem, determination of its spatial distribution is of importance. Satellite imageries can be used to map distribution extent using spectral characteristics which is a fundamental parameter in mapping. The aims of this study were to determine the spectral characteristics of corals and associated habitats and to map its spatial distribution using 2009 ALOS advanced visible and near infrared radiometer type 2 (AVNIR-2) satellite imagery. Results indicated that coral and habitats surrounding the area display variation in the spectral characteristics magnitude but displays similar spectral curve. Spectral characteristics from the corals and surrounding habitats were determined by presence of benthic microalgae and calcium carbonate. Maximum likelihood classification on the image produced five main classes. Spatial distribution of coral and associated habitats indicated five main zones which are sandy shore zone, sandy intertidal zone, seagrass zone, coral/submerged sandy zone and rocky zone. Distribution of live corals indicated coverage of 0.54 km2, sea grass (0.94 km2), sandy bottom (1.31 km2) and rocky shores (0.19 km2). The results of this study indicated that ALOS satellite data was able to determine variation in spectral characteristics of coral reefs and other habitats thus is capable of mapping the ecosystems spatial distribution

    Mathematical models for drug diffusion through the compartments of blood and tissue medium

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    This paper is an attempt to establish the mathematical models to understand the distribution of drug administration in human body through oral and intravenous routes. Three models were formulated based on diffusion process using Fick’s principle and law of mass action. The rate constants governing the law of mass action were used on the basis of the drug efficacy at different interfaces. The Laplace transform and eigenvalue methods were used to obtain the solution of the ordinary differential equations concerning the rate of change of concentration in different compartments viz. blood and tissue medium. The drug concentration in the different compartments has been computed using numerical parameters. The graphs plotted illustrate the variation of drug concentration with respect to time using MATLAB software. It has been observed from the graphs that the drug concentration decreases in the first compartment and gradually increases in other compartments.Keywords: Drug diffusion; Laplace transform; Eigenvalue metho

    DNA sequencing with MspA: molecular dynamics simulations reveal free-energy differences between sequencing and non-sequencing mutants

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    MspA has been identified as a promising candidate protein as a component of a nanopore-based DNA-sequencing device. However the wildtype protein must be engineered to incorporate all of the features desirable for an accurate and efficient device. In the present study we have utilized atomistic molecular dynamics to perform umbrella-sampling calculations to calculate the potential of mean force (PMF) profiles for translocation of the four DNA nucleotides through MspA. We show there is an energetic barrier to translocation of individual nucleotides through a mutant that closely resembles the wildtype protein, but not through a mutant engineered for the purpose of sequencing. Crucially we are able to quantify the change in free energy for mutating key residues. Thus providing a quantitative characterisation of the energetic impact of individual amino acid sidechains on nucleotide translocation through the pore of MspA

    Sexual harassment in campus: awareness, risk factor, and effect among students in higher learning institutions

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    This study is an ongoing project related the problem of sexual harassment in academic setting. The objectives are (i) to determine the awareness of sexual harassment among students in higher learning institutions, (ii) to identify the existence of sexual harassment in higher learning institutions, and (iii) to investigate the risk factors contributed to the action. Questionnaires were distributed to 351 students in a public university in East Coast Malaysia. The findings revealed that 58.6% of the respondents have been harassed at least once and majority of them were female. The greatest form of sexual harassment experience by the respondents was offensive behavior followed by unwanted sexual attention while sexual coercion contributed least toward the act. Majority of the respondents agreed that sexual harassment experienced affected their emotional greatly compared to education and productivity.Keywords: sexual harassment; students; higher learning institutio

    Forecasting rainfed sorghum yield using satellite-derived vegetation indices with limited ground-based information in Gadarif region, eastern Sudan

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    A practical crop growth and yield monitoring system based on satellite data is required and fundamental not only for precision farming, but also very useful for global food security enhancement. This study was performed to determine the optimal vegetation index and also to identify the best time for making a reliable crop yield forecast in one of the major sorghum-growing region (Gedarif State, Sudan). The study was also aimed to develop a simple yield prediction model which was later validated using an official yield data acquired during 2013 and 2014 cropping seasons from the Department of Information System and Statistical Analysis of the State Ministry of Agriculture, Gedarif State. The study used NASA’s multi-temporal MODerate resolution Imaging Spectroradiometer (MODIS) land products with limited ground information. Relationship between sorghum yield and crop reflectance indicated that normalized difference vegetation index (NDVI) at the third dekad of September (Sep.III) is the most appropriate to develop sorghum yield prediction model with higher R2 value of 0.77 (p<0.05) compared to other vegetation indices (normalized ratio vegetation index, NRVI and soil-adjusted vegetation index, SAVI). The plotting of estimated yield against actual yield during 2013 and 2014 cropping seasons revealed strong positive and linear correlations (R2 = 0.64 (p=0.06) and 0.74 (p<0.05), respectively with average R2 = 0.71 (p<0.001) for both seasons. This study concluded that a good prediction of rainfed sorghum yield could be achieved more than 30 days before harvesting with quick, accurate and cost-effective method compared to traditional field surveys

    Analisis Tingkat Kesejahteraan Rumah Tangga Nelayan Tradisional di Dusun Pulau Osi, Desa Eti, Kabupaten Seram Bagian Barat

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    Kehidupan masyarakat nelayan tradisional di Dusun Pulau Osi membawa tantangan dan dinamika tersendiri, khususnya dalam hal mencapai tingkat kesejahteraan yang optimal. Penelitian ini bertujuan untuk menganalisis tingkat kesejahteraan rumah tangga nelayan tradisional di Dusun Pulau Osi, Desa Eti, Kabupaten Seram Bagian Barat. Metode penelitian yang diterapkan melibatkan survei dengan pengumpulan data melalui wawancara langsung menggunakan kuesioner terstruktur kepada anggota rumah tangga nelayan tradisional. Hasil analisis menunjukkan bahwa tingkat kesejahteraan rumah tangga nelayan tradisional di Dusun Pulau Osi berada dalam kategori sedang. Faktor-faktor seperti kurangnya infrastruktur pendukung, keterbatasan akses ke pasar, dan dampak perubahan iklim menjadi hambatan utama yang signifikan mempengaruhi tingkat kesejahteraan mereka

    Personalized orodispersible films by hot melt ram extrusion 3d printing

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    This work demonstrated the feasibility of the extemporaneous preparation of maltodextrins orodispersible films (ODF) by hot-melt ram-extrusion 3D printing. This method consists of three simple technological operations which can be also implemented in a pharmacy setting. First, maltodextrins, drug, and other excipients are mixed in a mortar and wetted with the plasticizer (i.e. glycerine). Then, the mixture is fed in the chamber of the ram-extruder and heated. ODF are individually printed on the packaging material foil and sealed without further manipulations. The critical formulation attributes and process variables were investigated to define the processability space. In particular, the optimal conditions to print a mixture of maltodextrins/glycerine in 80/20 w/w ratio resulted: heating temperature: 85\ub0C; needle gauge: 18 G; needle-packaging material foil distance: 0.6 mm; maximum print rate: 50 mm/s; filling angle: 120\ub0. The maximum drug loading was about 40%, when paracetamol was used as model drug. The compounded ODF complied with USP and Ph. Eur. specifications for disintegration time (< 1 min). The dissolution pattern of paracetamol overlapped with that obtained from ODF with a similar composition prepared by the consolidated solvent casting technique, demonstrating the suitability of the proposed technology
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