1,874 research outputs found

    A Intelligent Fingerprint Based Biometric System for Personal Identification-A Survey

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    Today, because of the vulnerability of standard authentication system, law-breaking has accumulated within the past few years. Identity authentication that relies on biometric feature like face, iris, voice, hand pure mathematics, handwriting, retina, fingerprints will considerably decrease the fraud. so that they square measure being replaced by identity verification mechanisms. Among biometrics fingerprint systems are one amongst most generally researched and used. it\'s fashionable due to their easy accessibility. During this paper we tend to discuss the elaborated study of various gift implementation define strategies together with their comparative measures and result analysis thus as realize a brand new constructive technique for fingerprint recognition

    Application of Dried Blood Spots on Filter Paper for Detection of HIV Antibodies: Effect of Temperature and Duration of Storage

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    Background: Acquired immunodeficiecy syndrome (AIDS) is now adays a worldwide health problem affecting both the developed and developing countries. It has greater burden on the developing countries because of the increased cost of testing including specimen collection, transport, storage and laboratory examination. Moreover the present technique of collecting blood for diagnosis is associated with increased risk of infection, loss and contamination of specimen. This study aimed at evaluating the use of blood spot dried on filter paper (under different storage conditions) for detection of HIV antibodies in patient\'s serum as an alternative cheap and relatively safe method. Materials and methods: venous blood was collected from 100 known HIV infected patients and 50 healthy volunteers. Filter papesr (Whattman number 1) were soaked with the specimens, air-dried and then divided into 3 groups. Each group is containing a sample from each subject under study. The three groups were subjected to different storage conditions (room temperature, incubator at 37 o C and refrigerator at 4oC). PBS elutes from each group were tested for HIV antibodies using ELISA at regular intervals (48 hrs., 7,15, 30, 45, 60, 75, 90 and 105 days). Results: All the dried blood on filter paper remained positive for HIV antibodies for one month. Thereafter some of the specimens started to progressively show negative results. Specimens stored in the refrigerator were more stable for HIV antibodies than those kept at room temperature and the incubator. Discussion: In this study, the results of testing elutes of dried blood spots on filter paper for HIV antibodies were found to be 100% positive in concordance with those of testing serum samples. HIV antibodies were stable in all specimens for one month under the different storage conditions. Conclusion: dried blood spot on filter paper can remain positive for HIV antibodies for at least one month under different storage conditions. It can therefore be recommended as a cheap, simple and reliable technique for collection of blood for HIV testing under field surviellance as it does not require complex setting and instruments and moreover it eases transportation of specimen. Keywords: immunodeficiency syndrome (AIDS), storage, heparinized, ELISA.Sudan Journal of Medical Sciences Vol. 3 (2) 2008: pp. 147-15

    Quantifying the spatio-temporal patterns of settlement growth in a metropolitan region of Ghana

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    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s10708-016-9719-xRetrospective understanding of the magnitude and pace of urban expansion is necessary for effective growth management in metropolitan regions. The objective of this paper is to quantify the spatial– temporal patterns of urban expansion in the Greater Kumasi Sub-Region (GKSR)—a functional region comprising eight administrative districts in Ghana, West Africa. The analysis is based on Landsat remote sensing images from 1986, 2001 and 2014 which were classified using supervised maximum likelihood algorithm in ERDAS IMAGINE. We computed three complementary growth indexes namely; Average Annual Urban Expansion Rate, Urban Expansion Intensity Index (UEII) and Urban Expansion Differentiation Index to estimate the amount and intensity of expansion over the 28-year period. Overall, urban expansion in the GKSR has been occurring at an average annual rate of 5.6 %. Consequently, the sub-region’s built-up land increased by 313 km^2 from 88 km^2 in 1986 to 400 km^2 in 2014. The analysis further show that about 72 % of the total built-up land increase occurred in the last 13 years alone, with UEII value of 0.605 indicating a moderate intensity of urban expansion. Moreover, the metropolitan-core of the sub-region, being the focal point of urban development and the historical origins of expansion, accounted for more than half of the total built-up land increase over the 28-year period. Over the last decade and half however, urban expansion has spilled into the neighbouring peripheral districts, with the highest intensity and fastest rate of expansion occurring in districts located north and north east of the sub-regional core. We recommend a comprehensive regional growth management strategy grounded in effective strategic partnerships among the respective administrative districts to curb unsustainable urban expansion

    Functionalized Thermoplastic Polyurethane Nanofibers: An Innovative Triboelectric Energy Generator

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    A triboelectric nanogenerator (TENG) is one of the most significantly innovative microdevices for built-in energy harvesting with wearable and portable electronics. In this study, the forcespinning technology was used to synthesize a nanofiber (NF) mat-based TENG. Polyvinylidene fluoride (PVDF) membrane was used as the negative triboelectric electrode/pole, and chemically designed and functionalized thermoplastic polyurethane (TPU) was used as the positive electrode/pole for the TENG. The electronic interference, sensitivity, and gate voltage of the synthesized microdevices were investigated using chemically modified bridging of multi-walled carbon nanotubes (MWCNT) with a TPU polymer repeating unit and bare TPU-based positive electrodes. The chemical functionality of TPU NF was integrated during the NF preparation step. The morphological features and the chemical structure of the nanofibers were characterized using a field emission scanning electron microscope and Fourier-transform infrared spectroscopy. The electrical output of the fabricated MWCNT-TPU/PVDF TENG yielded a maximum of 212 V in open circuit and 70 µA in short circuit at 240 beats per minute, which proved to be 79% and 15% higher than the TPU/PDVF triboelectric nanogenerator with an electronic contact area of 3.8 × 3.8 cm2, which indicates that MWCNT enhanced the electron transportation facility, which results in significantly enhanced performance of the TENG. This device was further tested for its charging capacity and sensory performance by taking data from different body parts, e.g., the chest, arms, feet, hands, etc. These results show an impending prospect and versatility of the chemically functionalized materials for next-generation applications in sensing and everyday energy harvesting technology

    Exploring the factors contributing to increase in facility child births in Bangladesh between 2004 and 2017-2018

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    Although Bangladesh has gained rapid improvement in births at health facilities, yet far behind to achieve the SDG target. Assessing the contribution of factors in increased use of delivery at facilities are important to demonstrate. To explore the determinants and their contribution in explaining increased use of facility child births in Bangladesh. Reproductive-aged women (15-49 years) of Bangladesh. We used the latest five rounds (2004, 2007, 2011, 2014, 2017-2018) of Bangladesh Demographic and Health Surveys (BDHSs). The regression based classical decomposition approach has been used to explore the determinants and their contribution in explaining the increased use of facility child birth. A sample of 26,686 reproductive-aged women were included in the analysis, 32.90% (8780) from the urban and 67.10% (17,906) from the rural area. We observed a 2.4-fold increase in delivery at facilities from 2004 to 2017-2018, in rural areas it is more than three times higher than the urban areas. The change in mean delivery at facilities is about 1.8 whereas, the predicted change is 1.4. In our full sample model antenatal care visits contribute the largest predicted change of 22.3%, wealth and education contributes 17.3% and 15.3% respectively. For the rural area health indicator (prenatal doctor visit) is the largest drivers contributing 42.7% of the predicted change, hereafter education, demography and wealth. However, in urban area education and health contributed equally 32.0% of the change followed by demography (26.3%) and wealth (9.7%). Demographic variables (maternal BMI, birth order, age at marriage) contributing more than two-thirds (41.2%) of the predicted change in the model without the health variables. All models showed more than 60.0% predictive power. Health sector interventions should focus both coverage and quality of maternal health care services to sustain steady improvements in child birth facilities. [Abstract copyright: © 2023 The Authors. Published by Elsevier Ltd.

    Micellar parameters and thermodynamics of interaction of fluoroquinolone drugs with cetyldimethylethylammonium bromide

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    Interaction of fluoroquinolone antibiotic drugs, viz., ciprofloxacin hydrochloride, levofloxacin hemihydrate and lomefloxacin hydrochloride, with the cationic surfactant cetyldimethylethylammonium bromide (CDMEAB) has been studied by conductance measurements in water and in the presence of salts such as NaCl, Na2SO4 and Na3PO4·12H2O over the temperature range of 298.15–318.15 K. Two critical micelle concentrations (c*) are obtained for drug-CDMEAB systems in all the cases. The change of c* values of CDMEAB due to the addition of the drugs is indicative of the interaction between drugs and CDMEAB. Favourable micellization of drug-CDMEAB systems is observed in the presence of salts. The ∆G0m values were negative in all the cases. The values of ∆H0m and ∆S0m reveal that the binding interactions between drug and CDMEAB in water are both electrostatic and hydrophobic in nature. The existence of linear correlation between ∆H0m and ∆S0m values is observed in all cases

    A photoanode with hierarchical nanoforest TiO 2 structure and silver plasmonic nanoparticles for flexible dye sensitized solar cell

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    Due to unique photovoltaic properties, the nanostructured morphologies of TiO2 on flexible substrate have been studied extensively in the recent years for applications in dye sensitized solar cells (DSSCs). Microstructured electrode materials with high surface area can facilitate rapid charge transport and thus improve the light-to-current conversion efficiency. Herein we present an improved photoanode with forest like photoactive TiO2 hierarchical microstructure using a simple and facile hydrothermal route. To utilize the surface plasmon resonance (SPR) and hence increase the photon conversion efficiency, a plasmonic nanoparticle Ag has also been deposited using a very feasible photoreduction method. The branched structure of the photoanode increases the dye loading by filling the space between the nanowires, whereas Ag nanoparticles play the multiple roles of dye absorption and light scattering to increase the light-to-current conversion efficiency of the device. The branched structure provides a suitable matrix for the subsequent Ag deposition. They improve the charge collection efficiency by providing the preferential electron pathways. The high-density Ag nanoparticles deposited on the forest like structure also decrease the charge recombination and therefore improve the photovoltaic efficiency of the cells. As a result, the DSSC based on this novel photoanode shows remarkably higher photon conversion efficiency (ηmax = 4.0% and ηopt = 3.15%) compared to the device based on pristine nanowire or forest-like TiO2 structure. The flexibility of the device showed sustainable and efficient performance of the microcells
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