104 research outputs found

    An Experimental Study on Utilization of Iron Ore Tailings (IOT) and Waste Glass Powder in Concrete

    Get PDF
    Cement manufacturing industry is one of the carbon dioxide emitting sources besides deforestation burning of fossil fuels. The global warming is caused by the emission of green house gases, such as CO2, to the atmosphere. Among the greenhouse gases, CO2 contributes about 65% of global warming. The global cement industry contributes about 7% of green house gas emission to the earth’s atmosphere. In order to address environmental effects associated with cement manufacturing, there is a need to develop alternative binders to make concrete. Consequently extensive research is on going into the use of cement replacements, using many waste materials industrial by products. Efforts have been made in the concrete industry to use waste glass as partial replacement of cement and also in recent years almost every mineral producing country is facing the problem of better utilization of mine waste because of its accumulation lack of suitable storage space. In this study, finely powdered waste glass from industries and Iron Ore Tailings (IOT) produced from mining areas are used as a partial replacement  of cement and fine aggregates in concrete respectively.  This work examines the possibility of using Glass powder and iron ore tailing as a partial replacement of cement and fine aggregate in concrete. In the present study  Glass powder and Iron Ore Tailing  ( IOT )  are partially replaced by 10%, 20%, 30% and  40%  tested for its compressive, flexural strength for 7, 28 and 56 days of curing and were compared with those of conventional concrete. Keywords: Glass Powder – GP, Iron Ore Tailings – IOT, Conventional Concrete - C

    Multiplexed gradient descent: Fast online training of modern datasets on hardware neural networks without backpropagation

    Full text link
    We present multiplexed gradient descent (MGD), a gradient descent framework designed to easily train analog or digital neural networks in hardware. MGD utilizes zero-order optimization techniques for online training of hardware neural networks. We demonstrate its ability to train neural networks on modern machine learning datasets, including CIFAR-10 and Fashion-MNIST, and compare its performance to backpropagation. Assuming realistic timescales and hardware parameters, our results indicate that these optimization techniques can train a network on emerging hardware platforms orders of magnitude faster than the wall-clock time of training via backpropagation on a standard GPU, even in the presence of imperfect weight updates or device-to-device variations in the hardware. We additionally describe how it can be applied to existing hardware as part of chip-in-the-loop training, or integrated directly at the hardware level. Crucially, the MGD framework is highly flexible, and its gradient descent process can be optimized to compensate for specific hardware limitations such as slow parameter-update speeds or limited input bandwidth

    The toxicity of angiotensin converting enzyme inhibitors to larvae of the disease vectors Aedes aegypti and Anopheles gambiae

    Get PDF
    The control of mosquitoes is threatened by the appearance of insecticide resistance and therefore new control chemicals are urgently required. Here we show that inhibitors of mosquito peptidyl dipeptidase, a peptidase related to mammalian angiotensin-converting enzyme (ACE), are insecticidal to larvae of the mosquitoes, Aedes aegypti and Anopheles gambiae. ACE inhibitors (captopril, fosinopril and fosinoprilat) and two peptides (trypsin-modulating oostatic factor/TMOF and a bradykinin-potentiating peptide, BPP-12b) were all inhibitors of the larval ACE activity of both mosquitoes. Two inhibitors, captopril and fosinopril (a pro-drug ester of fosinoprilat), were tested for larvicidal activity. Within 24 h captopril had killed >90% of the early instars of both species with 3rd instars showing greater resistance. Mortality was also high within 24 h of exposure of 1st, 2nd and 3rd instars of An. gambiae to fosinopril. Fosinopril was also toxic to Ae. aegypti larvae, although the 1st instars appeared to be less susceptible to this pro-drug even after 72 h exposure. Homology models of the larval An. gambiae ACE proteins (AnoACE2 and AnoACE3) reveal structural differences compared to human ACE, suggesting that structure-based drug design offers a fruitful approach to the development of selective inhibitors of mosquito ACE enzymes as novel larvicides

    Idiopathic Oesophageal Dysmotility Disorder: Stridor Secondary to Megaesophagus

    Get PDF
    We present an interesting case of an elderly lady who presented with stridor caused by megaesophagus secondary to an acquired idiopathic dysmotility disorder. We discuss the aetiology and management of megaesophagus secondary to this condition and how it differs from megaesophagus secondary to achalasia

    L-arginine attenuates Interleukin-1β (IL-1β) induced Nuclear Factor Kappa-Beta (NF-κB) activation in Caco-2 cells.

    No full text
    BACKGROUND:Specific nutrients like L-arginine (L-Arg) ameliorate intestinal inflammation, however the exact mechanisms of this effect are unclear. We hypothesized the anti-inflammatory effects of L-Arg require active transport and metabolism by inducible nitric oxide synthase (iNOS) to generate nitric oxide (NO). To test this hypothesis we examined the effects of L-Arg, L-Arg transport activity, NO production and iNOS inhibitor on IL-1β-mediated NF-κB-activation in Caco-2 cells. METHODS:Caco-2 cells were cultured, transfected with a NF-κB promoter luciferase vector, incubated ± L-Arg, ± IL-1β and luciferase activity was measured. Using siRNA we inhibited the L-Arg cationic amino acid transporter system y+ (CAT1) expression and examined its effects on L-Arg transport activity and IL-1β-mediated NF-κB-activation. Finally, the effects of sodium nitroprusside (SNP, a NO donor) and Nω-nitro-L-arginine (NNA, an iNOS inhibitor) on IL-1β-mediated NF-κB-activation were examined. RESULTS:IL-1β increased NF-κB luciferase activity (8-fold) and NF-κB expression (mRNA and protein), both of these were significantly decreased by L-Arg. System y+ CAT1 siRNA decreased CAT1 expression, L-Arg transport activity and attenuated the inhibitory effects of L-Arg on NF- κB activity. SNP attenuated the IL-1β-induced increase in NF-κB luciferase activity and expression, whereas NNA diminished the inhibitory effects of L-Arg on IL-1β-inducible NF- κB luciferase activity. CONCLUSION:The inhibitory effects of L-Arg on IL-1β-mediated NF-κB-activation in Caco-2 cells involve L-Arg transport activity by CAT1, regulation of IL-1β-mediated increases in NF-κB expression, changes in iNOS expression and NO production. Our data suggest the inhibitory effects of L-Arg on NF-κB activation are mediated in part by iNOS since SNP preserves and NNA attenuates the effects of L-Arg on IL-1β-mediated NF-κB-activation and expression

    Crystal structures of Erythrina cristagalli lectin with bound N-linked oligosaccharide and lactose.

    No full text
    Erythrina cristagalli lectin (ECL) is a galactose-specific legume lectin. Although its biological function in the legume is unknown, ECL exhibits hemagglutinating activity in vitro and is mitogenic for T lymphocytes. In addition, it has been recently shown that ECL forms a novel conjugate when coupled to a catalytically active derivative of the type A neurotoxin from Clostridium botulinum, thus providing a therapeutic potential. ECL is biologically active as a dimer in which each protomer contains a functional carbohydrate-combining site. The crystal structure of native ECL was recently reported in complex with lactose and 20-fucosyllactose. ECL protomers adopt the legume lectin fold but form non-canonical dimers via the handshake motif as was previously observed for Erythrina corallodendron lectin. Here we report the crystal structures of native and recombinant forms of the lectin in three new crystal forms, both unliganded and in complex with lactose. For the first time, the detailed structure of the glycosylated hexasaccharide for native ECL has been elucidated. The structure also shows that in the crystal lattice the glycosylation site and the carbohydrate binding site are involved in intermolecular contacts through water-mediated interactions. Key words: crystal structure/Erythrina cristagalli lectin/ Erythrina corallodendron lectin/N-glycosylation/ protein–carbohydrate interactio

    On Subspaces of a Finsler Space Killing Vector Fields is in Generalized Conformal - Change

    No full text
    The present paper deals with the Killing vector fields in Generalized Conformal - change  on subspaces of a Finsler space   with respect to the infinitesimal transformation. Further, we proved the vector fields are killing form and orthogonal to each other

    Hutchinson–Gilford progeria syndrome with severe calcific aortic valve stenosis

    No full text
    Hutchinson–Gilford progeria syndrome (HGPS) is a rare premature aging syndrome that results from mutation in the Laminin A gene. This case report of a 12-year-old girl with HGPS is presented for the rarity of the syndrome and the classical clinical features that were observed in the patient. All patients with this condition should undergo early and periodic evaluation for cardiovascular diseases. However, the prognosis is poor and management is mainly conservative. There is no proven therapy available. Mortality in this uniformly fatal condition is primarily due to myocardial infarction, strokes or congestive cardiac failure between ages 7 and 21 years due to the rapidly progressive arteriosclerosis involving the large vessels
    corecore