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In view of the climate impact of aerosol Black Carbon (BC) over snow covered regions (through enhanced absorption of radiation as well as snow-albedo forcing), and in view of the increasing anthropogenic presence and influence in the northern polar regions, continuous long term measurements of airborne BC have been undertaken from the Svalbard region of Norwegian Arctic (Ny-Ålesund, 79°N, 12°E, 8 m a.s.l.). This study, employing data over a period of 4-years (2010–2013) have shown a consistent spring-time enhancement in BC concentrations, having a (climatological) seasonal mean value of ∼50.3 ± 19.5 ng m −3 , nearly 3-times higher than the lowest BC concentrations in summer (∼19.5 ± 6.5 ng m −3 ). Spectral variation of absorbance indicates that long-range transported biomass burning aerosols contribute as high as 25% to the high BC concentrations in the Arctic atmosphere in spring. Concurrent estimates of BC concentrations in the Arctic snow (for an ensemble of snow samples collected over a period of time during spring) showed values ranging from 0.6 ppb to 4.1 ppb. These values have been used to estimate the BC scavenging ratio (SR). Our studies revealed a mean value of SR ∼98 ± 46, which varied over wide range from 40 to 184 for individual samples. In a broader perspective, the seasonal variations of atmospheric BC concentrations at the Arctic are similar to those seen at the high altitude Himalayas; even though the concentrations are much lower at Arctic. It is found that synoptic conditions mainly influence the high altitude Himalayas, while the influences of local anthropogenic influences are not negligible at the Arctic in modulating the seasonal variations of absorbing aerosols. [ABSTRACT FROM AUTHOR]

Zr- and (Zr + F)-doped ZnO nanopowders were synthesized using a simple soft chemical route having Zr and F doping concentrations as 3 and 10 at.%, respectively. The structural, morphological, optical, magnetic and antibacterial properties of these samples are studied and compared with those of undoped ZnO. The X-ray diffractometer studies reveal that the synthesized nanopowders exhibit hexagonal wurtzite structure of ZnO, and the crystallite size increases after doping. The field effect scanning electron microscope and transition electron microscopy images show that the synthesized ZnO nanopowders have reduced grain size after doping. The dopant-induced room temperature ferromagnetism is observed from vibrating sample magnetometer studies. Enhancement in the antibacterial efficiency due to doping against three different bacterial strains,viz. Bacillus subtillis,Staphylococus aureusandPseudomonas aeruginosaare studied and reported. [ABSTRACT FROM AUTHOR]

This evidence-based study investigated the efficacy of the web based tool 'Pinterest' for teaching argumentative writing at the tertiary level. Principles of authentic learning are applied in this study. Two groups of ESL learners (n=28), 14 students as control group and 14 students as experimental group, participated in the study. A true experimental design was adopted. The control group was exposed to traditional instruction and the experimental group was exposed to web based instruction using Pinterest. The performance of both groups was analysed using paired T-Tests. The results revealed a discernible improvement in the performance of the experimental group. Finally, recommendations for efficacious integration of technology are enlisted. Despite many studies investigating the positive effects of web based instruction none of the studies till date have examined the efficacy of Pinterest for writing instruction. [ABSTRACT FROM AUTHOR]

[Display omitted] • High adsorption of Indole than aromatic hydrocarbons (P-xylene and Toluene) on the pristine/defected graphene sheet. • The reactivity of defect on adsorption of VOCs shows the influence of sheet type for adsorption rely on the type of the VOCs. • The significant changes in the electronic properties on adsorption of VOCs infers the high affinity of doped sheet than the pristine sheet. • The results enlightens the suitable sheet for the adsorption of VOCs hinge on the type of the VOCs adsorbate. Adsorption of volatile organic compounds (VOCs) which are a class of air pollutants affecting the environment and human health is considered as the favourable technology for enrichment, separation and utilization of VOCs. In the present work, the adsorption properties of air polluting carbocyclic and heterocyclic VOCs such as toluene, p-xylene and indole onto pristine/defected nanographene (with and without dopants) are investigated using density functional theory (DFT). Adsorption of indole is higher (−0.544 to −1.786 eV) in pristine/defected nanographene (with and without dopant) than p-xylene and toluene. The reactivity of defect on adsorption of VOCs is found high for indole with defected nanographene (DG) and toluene with DG-N indicating the influence of sheet type for adsorption rely on the type of the VOCs adsorbate. The charge transfer and type of interaction between the sheet and VOCs are interpreted using Hirshfeld charge analysis, QTAIM and RDG analysis. The influence of VOCs adsorption is high on the electronegativity and electrophilicity index of the pristine/defected nanographene whereas energy gap and hardness show less influence. The noticeable changes in the TDOS and energy gap on adsorption of VOCs with respect to the type of sheet infers that the doped defected sheet have high affinity than the pristine sheet moreover, the suitable sheet for adsorption of VOCs depends on the type of VOCs adsorbate. [ABSTRACT FROM AUTHOR]

In recent years the natural fibres have been more attractive. The natural fibres are technically enhanced by amalgamating with plastics. Types of natural fibres which can be used along with plastics are coir, luffa, hemp, jute, sisal and banana. The natural fibre have advantage over renewable resources and have high marketing appeal. Agricultural wastes can be used for the preparation of fibre reinforced composites in commercial purposes. Application of composite materials to structures have presented the need for the engineering analysis the present work focuses on the fabrication of coir and luffa reinforced polypropylene composite in desired shapes by the help of various structures of patterns and calculating its material characteristics (tensile strength, flexural rigidity, hardness, % gain of water, density and impact energy) by conducting tests like tensile test, flexural test, hardness test, water absorption test, density test, impact test, and SEM analysis. The results are assessed on sections of materials which identifies the use of the natural fibre reinforced polypropylene composite material for automotive application. [ABSTRACT FROM AUTHOR]

In this present study, the natural fibers such as kenaf and coconut spathe are reinforced in polymer matrix by hand layup process. Alkali treated coconut spathe and kenaf bast fibers are uniformly dispersed with epoxy resin and cured using tri-ethylene tetra amine (TETA) at 25 0 C. The weight proportion of the polymer matrix is maintained constantly 10% whereas the proportions of the fibers are altered within the composites. The mechanical properties like tensile, flexural, impact strengths are analyzed. Fracture analysis of fiber reinforced composites and the effect of alkali treatment on fibers are also observed using scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

Effects of gamma rays on the sex steroid hormone levels [testosterone (T), 11-ketotestosterone (11-KT) and 17β-estradiol (E2)] were studied in the freshwater fish Oreochromis mossambicus. Gamma radiation induced effects on hormone levels reported here for the first time in the fish. Since radionuclides released accidentally or during a nuclear disaster can contaminate inland water bodies, biomonitoring methods are required for assessing the impacts of certain dose levels of radiation that may ultimately result in ionizing radiation exposure to both humans and non-human biota. Three groups of (n=15 in each group) fishes were irradiated with a single dose of 60Co 10Gy, 15Gy and 20Gy with a duration of .33, .50 and .66min. Significant decrease of the hormone levels was seen at higher doses of 15Gy and 20Gy. The sex steroid hormone levels in the fishes are vital for sperm production, development, differential functions related to the physiology and reproductive behavior. This study serves as biomonitoring tool to assess the ionizing radiation effects on reproductive behavior of aquatic biota. [Copyright &y& Elsevier]

The aquaculture development has raised many environmental concerns worldwide due to its unregulated and unplanned expansion and outshined the advantages of increasing fish production by utilizing unused lands. The present study aimed to identify suitable sites for aquaculture by integrating land resources availability, source water bodies characteristics, unproductive lands soil quality, and infrastructure support into existing national aquaculture developmental laws using a spatial decision support system at Puducherry Union Territory, India. The seventeen influencing factors have been measured, mapped, quantified, and integrated through pairwise matrix based sensitive analysis and Geographical Information System (GIS). The spatial regulations of the Coastal Aquaculture Authority Act (2005) of India were applied to remove restricted regions such as mangroves, agricultural lands, lands used for other purposes, lands up to 200 m from high tide lines. Also, suitable buffer zones were established between the productive resources before delineating the potential aquaculture zones. The results showed that 416 ha was available for aquaculture, including 244 ha in most suitable, 81 ha in suitable, and 91 ha in moderately suitable classification levels. Combining sensitivity analysis and spatial model into resource characteristics, land availability, and aquaculture regulation laws will direct aquaculture sustainably and responsibly while protecting the other productive ecosystems characteristics. • Unplanned aquaculture has raised environmental issues worldwide. • Spatial data and techniques offer the way for regulated aquaculture planning. • The study combined land use, water, soil & infrastructure into policy guidelines. • Allocating spaces after spatial analysis for aquaculture promotes sustainability. [ABSTRACT FROM AUTHOR]

Abstract: Multitude of repair schemes are currently available to retrofit damaged civil engineering structures. Among them, efficient and effective method of repairing damaged structures is the application of Fiber Reinforced Plastics (FRP) because of its distinct advantages over other techniques. In the past, several structures have been successfully rehabilitated using the FRP techniques. To quote some examples, a calcareous masonry bell tower building, about 30 m in height and 1,200 m in width with a rectangular plan was retrofitted with FRP. Pushover curves for the retrofitted and un-retrofitted structures presented have disclosed that FRP intervention enhanced the seismic capacity of the structure. In the case of repairing of underwater pre- stressed piles, corrosion rate measurements indicated that the performance of the wrapped piles is consistently better than that the unwrapped controls. The paper presents a review of using the FRP techniques, their applications, case studies of repairing civil engineering structures, and appropriate concluding remarks. [Copyright &y& Elsevier]

Abstract: Glass Fiber-Reinforced Polymer (GFRP) composites are more and more used in the building trade for the set up of reinforcing and strengthening applications devices. As known, GFRP composites offer higher strength and Young modulus than traditional steel devices. The majority of these buildings were built before any provisions for earthquake loadings were established. The failures and damages reported in recent earthquakes attest to the need for efficient strengthening procedures. The effectiveness of increasing the shear strength of brick masonry coating with epoxy-bonding by Glass Fiber-Reinforced Polymer (GFRP) overlays to the exterior surfaces was evaluated. Out-of-plane failures are common in unreinforced masonry wall (UMW) constructed in seismic regions. This paper deals with the experimental characterization of the mechanical tensile and shear bond behavior of Glass Fiber-Reinforced Polymer (GFRP) sheets externally glued on masonry wall, in terms of load capacity and stress distribution along the bonded length. A combined experimental program was conducted to study the out-of-plane shear behavior of (i) Burned Clay Brick Masonry Walls and (ii) Strengthened with Glass Fiber Reinforced Polymer (GFRP) over the Burned Clay Brick Masonry Walls surface. [Copyright &y& Elsevier]

Abstract: A more reliable system for speechless patients to augment their limited communication abilities is presented in this paper. The normal person can’t understand the sign language shown by speechless patients .To facilitate the communication for them, the sign language is converted into an audible message through gesture recognition. Two things need to be considered in sign language-one is movement of hands and other is position of fingers. This is measured using MEMS accelerometer and Flex sensors. Using Fuzzy logic based Classifier the sensor values are classified and the MSP430 microprocessor is pre-programmed so as to send text output which in turn is converted into an audible message using speakjet IC. All these components will be placed on a wearable glove which will be worn by the user of this system. Data analysis is done using LABVIEW software. [Copyright &y& Elsevier]

Abstract: Simple Network Management Protocol (SNMP) is an internet standard protocol for managing devices on IP network and is one of the key components of NMS (Network management system). It is also used in a variety of application such as remote monitoring and controlling of the network nodes. Lowpan consist of large number of low-cost devices.lowpan faces several challenging issues such as small packet size, low bandwidth, low power, a large number of devices. In order to, overcome these issues, the 6lowpan was originated. The 6lowpan group has defined encapsulation and header compression mechanism that allow,ipv6 packets to be sent to and received from over lowpan based networks.6lowpan is a severely resource constrained network. Hence, existing SNMP protocol need to be modified. The 6lowpan-snmp is an extended modification of the SNMP.The SNMP is mainly used to manage a sensor node which has allocated IP address. These IP networks can be integrated with the 6lowpan by transmitting the SNMP packets over 6lowpan.this can be achieved by compressing SNMP packet and reduce the number of SNMP message over the network. This paper, tries to show effectiveness and feasibility of the proposed scheme on resource-constraint sensor network. [Copyright &y& Elsevier]

Abstract: A cold chain is a temperature controlled supply chain. The chain that brings the temperature-sensitive products from the factory to the consumer through an uninterrupted series of steps under a controlled temperature is usually called the “cold chain.” The goods follow complex logistic paths along this chain, and the final distribution often requires the use of refrigerated vehicles. While the temperature is easily controlled and monitored in the factory plants, the refrigerated vehicles can be a crucial point in the whole chain, since the products may undergo transient conditions during the loading operations or even during the whole transport process with great risk to the integrity of the goods. The refrigerated vehicles have to satisfy some thermal requirements, which are mainly related to the insulation and refrigeration capabilities, but this does not assure product integrity because of the unpredictable condition that may occur during the transportation and that could cause a significant change in the product temperature. The only reliable way of verifying the real integrity of the cold chain consists of monitoring the temperature of the products during their distribution. Application proposed in this paper deals with a wireless sensor network that has been specifically designed to monitor temperature-sensitive products during their distribution, with the aim of conforming to the cold-chain. Here sensors are placed along the cold boxes, such as product nodes communicate through a wireless channel with a base station which collects and processes the data sent by all nodes. This will continuously monitor temperature and multiple level of alert is provided in case of any undesirable condition in the product. The alert messages are forwarded to the vehicle driver and to the producer of the product. [Copyright &y& Elsevier]