120 research outputs found

    (SI10-056) Fear Effect in a Three Species Prey-predator Food-web System With Harvesting

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    Some recent studies and field experiments show that predators affect their prey not only by direct capture; they also induce fear in prey species, which reduces their reproduction rate. Considering this fact, we propose a mathematical model to study the fear effect of a middle predator on its prey in a three-species food web system with harvesting. The ecological feasibility of solutions to the proposed system is guaranteed in terms of positivity and boundedness. The local stability of stationary points in the proposed system is derived. Multiple co-existing stationary points for the proposed system are observed, which makes the problem more interesting compared to the similar models studied previously. The local existence of periodic solutions through Hopf bifurcations is additionally secured numerically in the case of both unique and multiple coexisting stationary points. It is also observed that the system can exhibit strange attractors in the form of chaos. A detailed numerical simulation is performed to ensure the existence of periodic solutions and period- doubling routes to chaos. Combined effects of fear and harvesting are also discussed numerically

    Genetic diversity analysis of Nardostachys jatamansi DC, an endangered medicinal plant of Central Himalaya, using random amplified polymorphic DNA (RAPD) markers

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    The genetic diversity analysis of eight populations of Nardostachys jatamansi DC. collected from different altitude of Central Himalaya has been attempted using 24 sets of random amplified polymorphic DNA (RAPD) primers. These sets of RAPD marker generated a total of 346 discernible and reproducible bands across the analysed population with 267 polymorphic and 75 monomorphic bands. The unweighted pair group method with arithmetic average (UPGMA) cluster analysis revealed three distinct clusters: I, II and III. The cluster I was represented by N. jatamansi population collected from Panwali Kantha (3200 m asl) and Kedarnath (3584 m asl), India together with Jumla (2562 m asl) from Nepal. Cluster II included collections from Har Ki Doon (3400 m asl) and Tungnath (3600 m asl) from India while Cluster III was represented by collections from Munsiyari (2380 m asl), Dayara (3500 m asl) and Valley of Flowers (3400 m asl) from India. The clustering of these populations was independent of variations in altitude and geographical locations. The genetic variations observed in different populations of Jatamansi might be due to environmental influences (biotic and abiotic), rather than altitude level differences. The abiotic (geographical or climatic differentiation) and biotic (pollination between population and seed dispersal) factors might be responsible for the genetic variations among these accessions of Jatamansi.Keywords: Genetic diversity, random amplified polymorphic DNA (RAPD), Nardostachys jatamansi, Central Himalaya, unweighted pair group method with arithmetic average (UPGMA)African Journal of Biotechnology Vol. 12(20), pp. 2816-282

    Effect of reflective practices on student learning in higher education—a real life approach

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    Validation of ideas are of paramount importance in STEM fields. Learning and converting ideas into practical application is the main purpose of technical education. Aviation is a highly safety sensitive field where confusion and mistakes are not acceptable. This brings serious challenges for academia that provides higher education in this field. A yearlong observation of the reflective practices was done at an Australian university while teaching aviation students to analyse outcomes of reflection on teaching and learning. Reflection provides a powerful opportunity to a teacher in improving teaching qualities and to identify training needs for enhancing teaching capabilities

    Genetic diversity of biovar 3 and 4 of Ralstonia solanacearum causing bacterial wilt of tomato using BOX- PCR, RAPD and hrp gene sequences

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    Genetic diversity of Ralstonia solanacearum, causal agent of bacterial wilt of tomato was assessed by using three different molecular methods such as random amplified polymorphism DNA (RAPD), BOX-PCR and hrp (hypersensitive response and pathogenicity) gene sequence analysis technique. Twelve isolates of Ralstonia solanacearum belonging to biovar 3 (9 isolates) and 4 (3 isolates) were collected from Northern parts of India including Himachal Pradesh and Uttarakhand states from infected tomato plants. Out of 16 primers used in RAPD fingerprinting, four primers (OPA-2, OPA-11, OPC-5, OPE-7) showed monomorphic bands and remaining 12 primers exhibited polymorphic amplified products of both the biovars of R. solanacearum. The primer OPE-10 showed the highest level of genetic diversity among the isolates. Ten isolates of R. solanacearum were classified into two clusters at 20 per cent similarity coefficient and cluster 1 represented all isolates of biovar 3 (UTT-23, UTT-10, UTT-26, HPT11, UTT-9, UTT-32, HPC-3) and cluster 2 comprised the biovar 4 (UTT-22, HPT-3, UTT-24). BOX-PCR fingerprint of R. solanacearum clearly distinguished biovar 3 and 4 grouped into two distinct clusters at 40% similarity coefficient. Cluster 1 represented all isolates of R. solanacearum biovar 3 and cluster 2 comprised the biovar 4 isolates. The isolates of R. solanacearum have genetic diversity in hrpB gene, but it could not differentiate the isolates of biovar 3 and 4. However, the biovars 3 and 4 of R. solanacearum can be genetically distinguished by using BOX- PCR and specific primer of RAPD

    \u3csup\u3e1\u3c/sup\u3eH, \u3csup\u3e15\u3c/sup\u3eN, and \u3csup\u3e13\u3c/sup\u3eC Chemical Shift Assignments of the Regulatory Domain of Human Calcineurin

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    Calcineurin (CaN) plays an important role in T-cell activation, cardiac system development and nervous system function. Previous studies have demonstrated that the regulatory domain (RD) of CaN binds calmodulin (CaM) towards the N-terminal end. Calcium-loaded CaM activates the serine/threonine phosphatase activity of CaN by binding to the RD, although the mechanistic details of this interaction remain unclear. It is thought that CaM binding at the RD displaces the auto-inhibitory domain (AID) from the active site of CaN, activating phosphatase activity. In the absence of calcium-loaded CaM, the RD is disordered, and binding of CaM induces folding in the RD. In order to provide mechanistic detail about the CaM–CaN interaction, we have undertaken an NMR study of the RD of CaN. Complete 13C, 15N and 1H assignments of the RD of CaN were obtained using solution NMR spectroscopy. The backbone of RD has been assigned using a combination of 13C-detected CON-IPAP experiments as well as traditional HNCO, HNCA, HNCOCA and HNCACB-based 3D NMR spectroscopy. A 15N-resolved TOCSY experiment has been used to assign Hα and Hβ chemical shifts

    Coffin-Siris syndrome with Mayer-Rokitansky-Küster-Hauser syndrome: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>We report the case of an unusual association of Coffin-Siris syndrome with Mayer-Rokitansky-Küster-Hauser syndrome. This association has never previously been reported in the medical literature.</p> <p>Case presentation</p> <p>A nine-year-old Indian girl was referred to our hospital for growth retardation, mental retardation, lax joints, generalized hypertrichosis, and hypoplastic fifth fingernails and toenails. A thorough medical examination and evaluation revealed she had phenotypic features of Coffin-Siris syndrome, with Mayer-Rokitansky-Küster-Hauser syndrome on radiological evaluation. The karyotype of our patient was normal.</p> <p>Conclusion</p> <p>In an unexplained case of mental retardation with facies suggestive of Coffin-Siris syndrome, association with Mayer-Rokitansky-Küster-Hauser syndrome should be considered and the patient should be evaluated for the same. Both of these syndromes may have a common pathogenesis, as yet unknown. This case report has broad implications, as similar cases in future may give insights into the pathogenesis of both these syndromes.</p

    Green synthesis of 5-methylpyridinium derivatives by C2-functionalization of pyridine-1-oxide derivatives and their antibacterial activity

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    An innovative green economic route has been developed for one pot multicomponent synthesis of 5-methylpyridinium derivatives by the reaction of 3-methylpyridine-1-oxide, aromatic aldehyde and β-ketoester catalysed by different ionic liquids (ILs), [BMIM][OH], [BMIM][Cl], [BMIM][Ac] in good to excellent yields. A relative study reinforced that [BMIM][OH] is the best IL for this C2-functionsalization reaction. The main highlights of this synthetic protocol are simple work-up, cost effectiveness and environmentally benign processing. The synthesized derivatives have been assessed for possible antibacterial activity against Staphylococcus aureus and Escherichia coli by using the microdilution method. The results of antibacterial activity suggests that compound 4I shows best antibacterial activity and other compounds show good to moderate activity

    A comparison of morphometric traits of sheep breeds of Karnataka in the farmers' flocks

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    The study revealed that the 4 sheep breeds of Karnataka differed significantly with respect to body weight and other physical traits. Kenguri and Bellary breeds of sheep were larger and heavier than Hassan and Mandya sheep breeds. Amongst them Kenguri rams were heaviest followed by Bellary, Mandya and Hassan but in ewes the above order was reversed in breeds of southern Karnataka. The overall difference in body weights of Kenguri and Bellary rams was 9.66 kg whereas in Hassan and Mandya rams it was 4.37 kg. The corresponding values in ewes were 4.06 kg and 1.5 kg. In ewes, the increase in magnitude of a morphometric trait from a lower age group to next higher age group was marginal. All the sheep breeds of Karnataka attained maximum weight at 8-tooth age

    Effect of Village-wide Use of Long-Lasting Insecticidal Nets on Visceral Leishmaniasis Vectors in India and Nepal: A Cluster Randomized Trial

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    Visceral leishmaniasis (VL) is a vector-borne disease causing at least 60,000 deaths each year amongst an estimated half million cases, and until recently there have been no significant initiatives to reduce this burden. However, in 2005, the governments of India, Bangladesh and Nepal signed a memorandum of understanding at the World Health Assembly in Geneva for the elimination of the disease by 2015. In the absence of an effective vaccine, the program will rely on the active detection and prompt treatment of cases throughout the endemic region, combined with a recurrent indoor residual spraying (IRS) of all villages at risk. Vector control programs based on IRS are notorious for failing to maintain comprehensive spray coverage over time owing to logistical problems and lack of compliance by householders. Long-lasting insecticidal nets (LNs) have been postulated as an alternative or complement to IRS. Here we describe how comprehensive coverage of LN in trial communities reduced the indoor density of sand flies by 25% compared to communities without LNs. This provides an indication that LNs could be usefully deployed as a component of the VL control program in the Indian subcontinent

    Greater Skeletal Gains in Ovary Intact Rats at Maturity Are Achieved by Supplementing a Standardized Extract of Butea monosperma

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    With a longitudinally designed study, we tested whether an acetone soluble fraction (ASF) from the stem bark of Butea monosperma resulted in maximizing bone gain in rats during growth and maturation and thus protected against osteopenia following ovariectomy (OVx) with concomitant treatment withdrawal. Female rats at weaning were given ASF (100 mg/kg/d) or vehicle for 12 weeks, and baseline skeletal parameters (micro-CT) and total plasma antioxidant status (TAS) were measured. At this stage, one group was OVx and the other group was sham operated. Vehicle group (untreated) after OVx was given E2 or continued with vehicle (OVx control). ASF group after OVx was given vehicle (ASF withdrawn, ASFW). After another 12 weeks, all groups were killed and various skeletal parameters were determined. ASF resulted in substantially better skeletal parameters and higher plasma TAS over control at maturity. Rats treated with ASF before OVx had reduced rates of bone loss compared to OVx control. Twelve weeks after OVx, the ASFW group exhibited better trabecular microarchitectural preservation, bone turnover profiles, increased cortical deposition, and biomechanical strength over the OVx control, and the effects were comparable to OVx + E2 group. ASF supplementation during skeletal growth could maximize bone accrual and could confer increased resistance to post-OVx osteopenia despite treatment withdrawal
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