125 research outputs found

    Design, fabrication and demonstration of a 1x20 multimode interference splitter for parallel biosensing applications

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    This paper presents the experimental achievement of a silicon-on-insulator 1x20 MMI splitter andsimulation evaluations of the TE-like and TM-like mode MMI splitters for parallel biosensing applications. Device fabrication technology and optical characterisation results are provided

    Building local capacities in the operation and management of an integrated solid waste management programme; Experience of Ampara District, Eastern Sri Lanka

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    Open dumping and burning of wastes in the environmental sensitive areas were common practices in almost all the local authorities in Ampara district. It had become a big threat to public health, the beautiful natural environment and to the local economy. The Local Authorities of the District often faced severe difficulties in the management of solid waste in an environmentally, socially and economically feasible manner. The lack of technical and financial capacities to apply and practice the newly developed waste management guidelines and policies further aggravated this situation.Having identified the gravity  and the importance of this serious environmental issue, the Department of Assistant Commissioner of Local Government of Ampara District, with the financial assistance of the European Union and the technical assistance of the United Nations Office for Project Services (UNOPS), is currently implementing an Integrated Solid Waste Management Programme (ISWMP) in 12 local authorities of the District. This ISWMP is completely being operated with the full coordination of the District Office of the Central Environmental Authority, Ampara. The UNOPS, as part of its technical assistance, has constructed solid waste management facilities such as 7 engineered landfills, one Waste Transfer Station, 4 Recycling Centers, 5 compost yards, well developed collection systems  as well as provided with capability building/training assistance aiming to establish an effective and efficient solid waste management system for the District. These  facilities are now completed,  already in use and operational. With these facilities in place, and with the continued support from UNOPS in providing institutional and capacity building assistance to the LA officers and staff, haphazard dumping and littering of waste in certain areas of the LAs have now been stopped. Thus 45,000 urban households or 58% of the total urban population are benefitted under thisprogramme with a total collection of 137tonnes of wastes per day through this programme. Out of this 137tonnes of waste, 59 tonnes are collected from cluster systems involving five local authorities while the balance from the other non-clustered Local Authorities.The paper will also present the processes and methodologies to improve the landfill practices from the open dumping practices to controlled tipping and then to engineered landfills  among the implementing local authorities. It will also highlight interventions/strategies to ensure sustainability of the operation and their management through the introduction of a User Fee system/Service Charge which is currently being implemented in 04  Local Authorities. This collected User Fee covers about 80% of cost of collection of waste which would otherwise been spent through their normal budget.Key words: Integrated Solid Waste Management, Ampara, haphazard dumping, controlled tipping, engineered landfill

    Wheat (Triticum aestivum l.) production under drought and heat stress – adverse effects, mechanisms and mitigation: A review

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    Heat and drought stresses are the most important abiotic factors that reduce crops productivity by affecting various physiological and biochemical processes. Thus, selecting cultivars with better drought or heat stress tolerance or breeding for stress tolerance will be helpful in enhancing crop productivity under harsh environments. This review elaborates the physiological basis of high temperature and drought stress tolerance in wheat which can be used as selection criteria in wheat breeding program. In addition, some agronomic selection criteria which are valid and useful in selecting stress tolerant wheat species and cultivars. The review also discussed the valid usage of stress tolerance indices (such as mean productivity (MP), geometric mean productivity (GMP), yield index (YI), yield stability index (YSI), relative productivity (RP%), stress susceptibility index (SSI), and the tolerance index (TOL)) to scan the genotypes against drought and heat stress. Beside these, exogenous application of stress signaling compounds, osmolytes, or certain inorganic salts play a vital role for alleviating adverse effects of abiotic stresses for sustainable wheat production. In addition, applications for soil amendments will also helpful in increasing wheat crop productivity under stressful conditions. All these strategies may be helpful to meet the food demands of the increasing population.Fil: El Sabagh, A.. University of Kafrelsheikh; EgiptoFil: Hossain, A.. Bangladesh Agricultural Research Institute; BangladeshFil: Barutçular, C.. University of Çukurova; TurquĂ­aFil: Islam, Mohammad Sirajul. Hajee Mohammad Danesh Science and Technology University; BangladeshFil: Awan, S. I.. University of the Poonch; PakistĂĄnFil: Galal, A.. University of Kafrelsheikh; EgiptoFil: Iqbal, M. A.. University of the Poonch; PakistĂĄnFil: Sytar, O.. Slovak University of Agriculture; EslovaquiaFil: Yildirim, M.. Dicle University; TurquĂ­aFil: Meena, R. S.. Inistitute of Agricultural Sciences; IndiaFil: Fahad, S.. The University of Swabi; PakistĂĄnFil: Najeeb, U.. The University of Queensland; AustraliaFil: Konuskan, O.. Mustafa Kemal University; TurquĂ­aFil: Habib, R. A.. Bahauddin Zakariya University; PakistĂĄnFil: Llanes, Analia Susana. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas FisicoquĂ­micas y Naturales. Instituto de Investigaciones AgrobiotecnolĂłgicas - Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones AgrobiotecnolĂłgicas; Argentina. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Hussain, S.. University of Agriculture; PakistĂĄnFil: Farooq, M.. Sultan Qaboos University; OmĂĄnFil: Hasanuzzaman, M.. Sher-e-Bangla Agricultural University; BangladeshFil: Abdelaal, K. H.. Kafrelsheikh University; EgiptoFil: Hafez, Y.. Kafrelsheikh University; EgiptoFil: Cig, F.. Siirt University; TurquĂ­aFil: Saneoka, H.. Hiroshima University; JapĂł

    Association of Methylentetraydrofolate Reductase (MTHFR) 677 C > T gene polymorphism and homocysteine levels in psoriasis vulgaris patients from Malaysia: a case-control study

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    <p>Abstract</p> <p>Background</p> <p>The methylenetetrahydrofolate reductase (MTHFR) enzyme catalyzes the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate and methyl donors. The methyl donors are required for the conversion of homocysteine to methionine. Mutation of MTHFR 677 C > T disrupts its thermostability therefore leads to defective enzyme activities and dysregulation of homocysteine levels.</p> <p>Methods</p> <p>This case-control study (n = 367) was conducted to investigate the correlation of the MTHFR gene polymorphism [NM_005957] and psoriasis vulgaris amongst the Malaysian population. Overnight fasting blood samples were collected from a subgroup of consented psoriasis vulgaris patients and matched controls (n = 84) for the quantification of homocysteine, vitamin B<sub>12 </sub>and folic acid levels.</p> <p>Results</p> <p>There was no significant increase of the MTHFR 677 C > T mutation in patients with psoriasis vulgaris compared with controls (<it>χ</it><sup>2 </sup>= 0.733, p = 0.392). No significant association between homocysteine levels and MTHFR gene polymorphism in cases and controls were observed (F = 0.91, df = 3, 80, p = 0.44). However, homocysteine levels in cases were negatively correlated with vitamin B<sub>12 </sub>(r = -0.173) and folic acid (r = -0.345) levels. Vitamin B<sub>12 </sub>and folic acid levels in cases were also negatively correlated (r = -0.164).</p> <p>Conclusions</p> <p>Our results indicate that there was no significant association between the MTHFR gene polymorphism and psoriasis vulgaris in the Malaysian population. There was no significant increase of the plasma homocysteine level in the psoriasis patients compared to the controls.</p

    Evaluation of gut modulatory and bronchodilator activities of Amaranthus spinosus Linn.

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    Background The aqueous-methanolic extract of Amaranthus spinosus (A. spinosus Linn.,) whole plant, was studied for its laxative, spasmolytic and bronchodilator activities to validate some of its medicinal uses. Methods The crude extract of A. spinosus was studied in-vivo for bronchodilator and laxative activities and in-vitro using isolated tissue preparations which were mounted in tissue baths assembly containing physiological salt solutions, maintained at 37°C and aerated with carbogen, to assess the spasmolytic effect and to find out the possible underlying mechanisms. Results In the in-vivo experiments in mice, the administration of A. spinosus increased fecal output at doses of 100 and 300 mg/kg showing laxative activity. It also inhibited carbachol-induced bronchospasm in anesthetized rats at 1, 3, 10 and 30 mg/kg indicative of bronchodilator activity. When tested on isolated gut preparations, the plant extract showed a concentration-dependent (0.01-10.0 mg/ml) spasmogenic effect in spontaneously contracting rabbit jejunum and guinea-pig ileum. The spasmogenic effect was partially blocked in tissues pretreated with atropine (0.1 ÎŒM). When tested on K+ (80 mM)-induced sustained contractions in isolated rabbit jejunum, the plant extract caused complete relaxation and also produced a shift in the Ca++ concentration-response curves (CRCs) towards right, similar to diltiazem. In rabbit trachea, the plant extract completely inhibited K+ (80 mM) and carbachol (CCh, 1 ÎŒM)-induced contractions at 1 mg/ml but pretreatment of tissue with propranolol (1 ÎŒM), caused around 10 fold shift in the inhibitory CRCs of the plant extract constructed against CCh-induced contraction. The plant extract (up to 0.3 mg/ml) also increased both force and rate of spontaneous contractions of isolated guinea-pig atria, followed by relaxation at higher concentration (1.0-5.0 mg/ml). The cardio-stimulant effect was abolished in the presence of propranolol, similar to that of isoprenaline. Activity-directed fractionation revealed that the spasmolytic component(s) was separated in the organic fraction, whereas the spasmogenic component was concentrated in the aqueous fraction. Conclusion These results indicate that A. spinosus possesses laxative activity partially mediated through cholinergic action. The spasmolytic effect was mediated through calcium channel blocking (CCB), while bronchodilator activity through a combination of ÎČ-adrenergic and CCB pathways, which may explain the traditional uses of A. spinosus in gut and airways disorders

    Bioaccumulation and ecotoxicity of carbon nanotubes

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    Carbon nanotubes (CNT) have numerous industrial applications and may be released to the environment. In the aquatic environment, pristine or functionalized CNT have different dispersion behavior, potentially leading to different risks of exposure along the water column. Data included in this review indicate that CNT do not cross biological barriers readily. When internalized, only a minimal fraction of CNT translocate into organism body compartments. The reported CNT toxicity depends on exposure conditions, model organism, CNT-type, dispersion state and concentration. In the ecotoxicological tests, the aquatic organisms were generally found to be more sensitive than terrestrial organisms. Invertebrates were more sensitive than vertebrates. Single-walled CNT were found to be more toxic than double-/multi-walled CNT. Generally, the effect concentrations documented in literature were above current modeled average environmental concentrations. Measurement data are needed for estimation of environmental no-effect concentrations. Future studies with benchmark materials are needed to generate comparable results. Studies have to include better characterization of the starting materials, of the dispersions and of the biological fate, to obtain better knowledge of the exposure/effect relationships

    Nicotinamide Inhibits Alkylating Agent-Induced Apoptotic Neurodegeneration in the Developing Rat Brain

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    BACKGROUND: Exposure to the chemotherapeutic alkylating agent thiotepa during brain development leads to neurological complications arising from neurodegeneration and irreversible damage to the developing central nerve system (CNS). Administration of single dose of thiotepa in 7-d postnatal (P7) rat triggers activation of apoptotic cascade and widespread neuronal death. The present study was aimed to elucidate whether nicotinamide may prevent thiotepa-induced neurodegeneration in the developing rat brain. METHODOLOGY/PRINCIPAL FINDINGS: Neuronal cell death induced by thiotepa was associated with the induction of Bax, release of cytochrome-c from mitochondria into the cytosol, activation of caspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP-1). Post-treatment of developing rats with nicotinamide suppressed thiotepa-induced upregulation of Bax, reduced cytochrome-c release into the cytosol and reduced expression of activated caspase-3 and cleavage of PARP-1. Cresyl violet staining showed numerous dead cells in the cortex hippocampus and thalamus; post-treatment with nicotinamide reduced the number of dead cells in these brain regions. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) and immunohistochemical analysis of caspase-3 show that thiotepa-induced cell death is apoptotic and that it is inhibited by nicotinamide treatment. CONCLUSION: Nicotinamide (Nic) treatment with thiotepa significantly improved neuronal survival and alleviated neuronal cell death in the developing rat. These data demonstrate that nicotinamide shows promise as a therapeutic and neuroprotective agent for the treatment of neurodegenerative disorders in newborns and infants

    X-ray screening identifies active site and allosteric inhibitors of SARS-CoV-2 main protease

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    The coronavirus disease (COVID-19) caused by SARS-CoV-2 is creating tremendous human suffering. To date, no effective drug is available to directly treat the disease. In a search for a drug against COVID-19, we have performed a high-throughput X-ray crystallographic screen of two repurposing drug libraries against the SARS-CoV-2 main protease (M^(pro)), which is essential for viral replication. In contrast to commonly applied X-ray fragment screening experiments with molecules of low complexity, our screen tested already approved drugs and drugs in clinical trials. From the three-dimensional protein structures, we identified 37 compounds that bind to M^(pro). In subsequent cell-based viral reduction assays, one peptidomimetic and six non-peptidic compounds showed antiviral activity at non-toxic concentrations. We identified two allosteric binding sites representing attractive targets for drug development against SARS-CoV-2

    Author Correction: Multi-ancestry genome-wide association analyses improve resolution of genes and pathways influencing lung function and chronic obstructive pulmonary disease risk

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    Correction to: Nature Geneticshttps://doi.org/10.1038/s41588-023-01314-0, published online 13 March 2023. In the version of the article initially published, the sample sizes in the main text and Supplementary Tables 1 and 2 were incorrect. In the abstract, the last paragraph of the Introduction, the first paragraph of the Results, the top box in Figure 1a and the Supplementary Information, the total sample size has been corrected from 580,869 to 588,452 participants and the size of the European cohort from 468,062 to 475,645. Some of the effect sizes in Supplementary Table 14 (columns W, Z, AC, AF) had the wrong sign. There was also an error in Supplementary Table 3 where the sample size instead of the variant count was shown for EXCEED. The errors do not affect the conclusions of the study. Additionally, two acknowledgments for use of INTERVAL pQTL and Lung eQTL consortium data were omitted from the Supplementary Information. These errors have been corrected in the Supplementary Information and HTML and PDF versions of the article

    Proceedings of Abstracts, School of Physics, Engineering and Computer Science Research Conference 2022

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    © 2022 The Author(s). This is an open-access work distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. For further details please see https://creativecommons.org/licenses/by/4.0/. Plenary by Prof. Timothy Foat, ‘Indoor dispersion at Dstl and its recent application to COVID-19 transmission’ is © Crown copyright (2022), Dstl. This material is licensed under the terms of the Open Government Licence except where otherwise stated. To view this licence, visit http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: [email protected] present proceedings record the abstracts submitted and accepted for presentation at SPECS 2022, the second edition of the School of Physics, Engineering and Computer Science Research Conference that took place online, the 12th April 2022
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