In this study, an atmospheric pressure dielectric barrier discharge-based argon plasma jet has been modeled using COMSOL Multiphysics, which is based on the finite element method. The fluid dynamics and plasma modules of COMSOL Multiphysics code have been used for the modeling of the plasma jet. The plasma parameters, such as electron density, electron temperature, and electrical potential, have been examined by varying the electrical parameters, that is, supply voltage and supply frequency for both cases of static and with the flow of argon gas. The argon gas flow rate was fixed at 1 l/min. Ring electrode arrangement is subjected to a range of supply frequencies (10–25 kHz) and supply voltages (3.5–6 kV). The experimental results of the ring electrode configuration have been compared with the simulation analysis results. These results help in establishing an optimized operating range of the dielectric barrier discharge-based cold plasma jet in the glow discharge regime without arcing phenomenon. For the applied voltage and supply frequency parameters examined in this work, the discharge was found to be consistently homogeneous and displayed the characteristics of atmospheric pressure glow discharge.

The pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has emerged as a serious global public health issue. Since the start of the outbreak, the importance of hand-hygiene and respiratory protection to prevent the spread of the virus has been the prime focus for infection control. Health regulatory organisations have produced guidelines for the formulation of hand sanitisers to the manufacturing industries. This review summarises the studies on alcohol-based hand sanitisers and their disinfectant activity against SARS-CoV-2 and related viruses. The literature shows that the type and concentration of alcohol, formulation and nature of product, presence of excipients, applied volume, contact time and viral contamination load are critical factors that determine the effectiveness of hand sanitisers.

Pollinator declines coupled with increasing demand for insect pollinated crops have the potential to cause future pollinator shortages for our most nutritious and valuable crops. Ensuring adequate crop pollination may necessitate a shift in pollination management, from one that primarily relies on the managed European honeybee (Apis mellifera L.) to one that integrates alternative pollinators. While a growing body of scientific evidence supports significant contributions made by naturally occurring, native bees for crop pollination, translating research to practice requires buy-in from growers. The intention of agricultural extension is to address grower needs and concerns; however, few studies have assessed grower knowledge, perceptions and attitudes about native pollinators. Here we present findings from questionnaire-based surveys of over 600 apple growers in New York State and Pennsylvania, coupled with ecological data from bee surveys. This hybrid sociological and biological survey allows us to compare grower knowledge and perceptions to an actual pollinator census. While up to 93% of respondents highly valued importance of native bees, 20% growers did not know how much native bees actually contribute to their orchard pollination. Despite the uncertainty, a majority of growers were open to relying on native bees (up to 60% in NY and 67% in PA) and to making low-cost changes to their farm's management that would benefit native pollinators (up to 68 in NY and 85% in PA). Growers consistently underestimated bee diversity, but their estimates corresponded to major bee groups identifiable by lay persons, indicating accurate local knowledge about native bees. Grower reliance on honeybees increased with farm size; because native bee abundance did not measurably decrease with farm size, renting honeybees may be motivated by risk avoidance rather than grower perception of lower native bee activity. Demonstrated effectiveness of native pollinators and clear guidelines for their management were the most important factors influencing grower decision to actively manage orchards for native bees. Our results highlight a pressing need for an active and research-based extension program to support diversification of pollination strategies in the region.

In the present study, unsteady MHD boundary layer flow of a rotating Walters’-B fluid (viscoelastic fluid) over an infinite vertical porous plate embedded in a uniform porous medium with fluctuating wall temperature and concentration taking Hall and ion-slip effects into consideration is discussed. The MHD flow in the rotating fluid system is induced due to the non-torsional oscillations of the plate in its own plane and the buoyancy forces arises from temperature and concentration differences in field of gravity. The partial differential equations governing the fluid motion are solved analytically by using regular perturbation and variable separable methods by assuming very small viscoelastic parameter. Solution for velocity field in the case when natural frequency due to rotation and Hall current is equals to the frequency of oscillations i.e. in the case of resonance is also obtained. In order to note the influences of various system parameters and to discuss the important flow characteristics, the numerical results for fluid velocity in the non-resonance case, temperature and species concentration are computed and depicted graphically versus boundary layer parameter whereas skin friction, Nusselt number and Sherwood number at the plate are computed and presented in tabular form. An interesting observation recorded that there arises flow reversal in the primary flow direction due to high rotation. When natural frequency is greater than the frequency of oscillations the fluid velocity in the primary flow direction is maximum at the plate whereas incase when natural frequency is smaller than the frequency of oscillations, it is maximum in the neighborhood of the plate.

This research article addresses the effect of fillers on the high-temperature corrosion behavior of AISI 347 weld joints. Multi-pass pulsed current gas tungsten arc welding was carried out on 6.67 mm thick plates of AISI 347 using three different fillers namely ER347, ER2553, and ERNiCrMo-3. The fusion zone microstructures of AISI 347 employing ER2553 and ERNiCrMo-3 exhibited columnar and dendritic grain growth; whereas vermicular delta ferrite was observed at the fusion zone of ER347 welds. Tensile studies showed that the weld employing ERNiCrMo-3 exhibited better tensile strength than the parent metal. High-temperature corrosion studies were carried out on the fusion zones by exposing the coupons to an aggressive, synthetic molten-salt incinerator environment containing 40% Na2SO4–40% K2SO4–10% NaCl–10% KCl at 650 °C for 50 cycles. The studies attested that the fusion zone employing ERNiCrMo-3 exhibited better corrosion resistance than the other two fillers used in the study. Spallation of oxides was witnessed due to the dissolution of Cr2O3 in the ER347 and ER2553 fusion zones. The hot corroded samples were characterized using surface analytical techniques.

Plant breeding makes genetic gains over years, so growing newer varieties generally provides greater benefits than growing older ones. However, in low-altitude districts of Nepal, a few rice varieties covered 75% of the rice area and were more than 20 years old (first paper in this series). We test here if this slow rate of adoption of new varieties could be accelerated using a participatory method, Informal Research and Development (IRD), where packets of seeds of new rice varieties are widely distributed to many farmers. From 2008 to 2011, over 117 000 IRD packets were distributed in 18 districts of the Nepal Terai, including over 70 000 of three released varieties from a client-oriented breeding (COB) programme in Nepal. The IRD significantly increased the adoption of the three COB varieties. The benefits obtained by farmers in a single growing season equal the costs of IRD, if for every 75 kits distributed an additional 1 ha is grown. This assumes that the new varieties produce a 10% increase in yield (lower than that evidenced in their release proposals). On an average, fewer than three IRD kits were distributed for each hectare of a new variety grown by farmers in 2011. Furthermore, the effectiveness of IRD could be increased 1.2 to 2.7 fold (depending on the COB variety) if the IRD distribution were to be restricted to the region where the variety was most accepted. The best comparison of IRD with extension by the conventional system was their popularity compared with similar-aged varieties that had been promoted in the two systems. The adoption of three COB varieties was about twicethat of three varieties from the National Rice Research Programme (NRRP) that were closest in release date to the COB varieties. Unlike cost effectiveness assessed by hectares grown per IRD kit distributed, this comparison can only indicate efficacy because, as well as extension method, many factors influenced the adoption rates of the COB and NRRP varieties. The costs of IRD are small, both relative to the cost of breeding new varieties and to the benefits gained; so it is one of the simplest and most cost-effective interventions to increase agricultural productivity.

Farmers who continue to grow old and obsolete varieties do not gain the benefits they could get from growing newer ones. Given the potential large scale of these foregone benefits, relatively few studies have examined the age of varieties that farmers grow. In three surveys, members of over 3300 households were interviewed to find the rice varieties they grew in 2008 and 2011 in 18 districts in the Terai, the low-altitude region of Nepal. This provided the first description of detailed geographical patterns of adoption of rice varieties and their ages that were repeated over time. There were large differences between district and individual varieties that showed specific geographical patterns of adoption. Such detailed knowledge on spatial diversity of varieties is invaluable for planning extension activities and developing breeding programmes, and cheaper ways than household surveys of collecting this information are discussed. Some of the factors considered important in determining this complex pattern of adoption were seed availability, growing environments that differed from east to west and the continued popularity of varieties once they had established markets. Rice diversity was low because a small number of rice varieties occupied large areas. In 2011, nine varieties covered at least 75% of the total rice area in western districts, just four in central districts and eight in eastern districts. Of these, most were released before 1995 resulting in a high average age of the predominant varieties – they always had an average age of over 20 years no matter which region or year was considered. Even though there were some large changes in varietal composition from 2008 to 2011, the average age of the predominant varieties remained almost the same. In a second paper in this series, we examine how these very low varietal replacement rates, that reduce yields and increase risk to farmers, can be accelerated using a participatory research for development approach called Informal Research and Development (IRD) (Joshi et al., 2012).

Deriving glacier outlines from satellite data has become increasingly popular in the past decade. In particular when glacier outlines are used as a base for change assessment, it is important to know how accurate they are. Calculating the accuracy correctly is challenging, as appropriate reference data (e.g. from higher-resolution sensors) are seldom available. Moreover, after the required manual correction of the raw outlines (e.g. for debris cover), such a comparison would only reveal the accuracy of the analyst rather than of the algorithm applied. Here we compare outlines for clean and debris-covered glaciers, as derived from single and multiple digitizing by different or the same analysts on very high- (1 m) and medium-resolution (30 m) remote-sensing data, against each other and to glacier outlines derived from automated classification of Landsat Thematic Mapper data. Results show a high variability in the interpretation of debris-covered glacier parts, largely independent of the spatial resolution (area differences were up to 30%), and an overall good agreement for clean ice with sufficient contrast to the surrounding terrain (differences ∼5%). The differences of the automatically derived outlines from a reference value are as small as the standard deviation of the manual digitizations from several analysts. Based on these results, we conclude that automated mapping of clean ice is preferable to manual digitization and recommend using the latter method only for required corrections of incorrectly mapped glacier parts (e.g. debris cover, shadow).

In this work we present an experimental study where energetic ions were produced in an underdense 2.5 × 1019 cm−3 plasma created by a 50 fs Ti:Sapphire laser with 5 TWs of power. The plasma comprises 95% He and 5% N2 gases. Ionization-induced trapping of nitrogen K-shell electrons in the laser-induced wakefield generates an electron beam with a mean energy of 40 MeV and ~1 nC of charge. Some of the helium ions at the wake–vacuum interface are accelerated with a measured minimum ion energy of He1+ ions of 1.2 MeV and He2+ ions of 4 MeV. The physics of the interaction is studied with 2D particle-in-cell simulations. These reveal the formation of an ion filament on the axis of the plasma due to space charge attraction of the wakefield-accelerated high-charge electron bunch. Some of these high-energy electrons escape the plasma to form a sheath at the plasma–vacuum boundary that accelerates some of the ions in the filament in the forward direction. Electrons with energy less than the sheath potential cannot escape and return to the plasma boundary in a vortex-like motion. This in turn produces a time-varying azimuthal magnetic field, which generates a longitudinal electric field at the interface that further accelerates and collimates the ions.

The study of bovine mammary gland functional genomics requires appropriate cDNA library collections to access gene expression patterns from different developmental and physiological stages. The present study was undertaken with the objective to identify candidate genes involved in the process of increased milk synthesis following 0, 48 and 96 h of recombinant bovine somatotropin (rbST) treatment to Surti buffalo (Bubalus bubalis) through differential display reverse transcriptase PCR (DDRT-PCR). Of a total 50 sequenced DD bands, 64% of ESTs were differentially expressed (appeared only in post-treatment samples, i.e. 48 h and 96 h) and 36% were up-regulated after rbST treatment. Of the ESTs 32%were found to be located on Bos taurus chromosome 24 (equivalent to buffalo chromosome 22), whereas 16% of ESTs could not be mapped, indicating that they are specific to buffalo. Quantitative real time PCR assay of 15 ESTs revealed transcript level surge in 13 ESTs, and decline in one EST, while one showed up-regulation in expression level at 48 h while down-regulation at 96 h. This study indicates more than 30 novel transcripts, with unknown function, involved in increased milk synthesis and also the involvement of many more genes in the physiology of milk production than once thought.

Experiments demonstrate the ~77× amplification of 0.5 to 3.5-ps pulses of seed light by interaction with Langmuir waves in a low density (1.2 × 1019 cm−3) plasma produced by a 1-ns, 230-J, 1054-nm pump beam with 1.2 × 1014 W/cm2 intensity. The waves are strongly damped (kλD = 0.38, Te = 244 eV) and grow over a ~ 1 mm length, similar to what is experienced by scattered light when it interacts with crossing beams as it exits an ignition target. The amplification reduces when the seed intensity increases above ~1 × 1011 W/cm2, indicating that saturation of the plasma waves on the electron kinetic time scale (<0.5 ps) limits the scatter to ~1% of the available pump energy. The observations are in agreement with 2D PIC simulations in this case.

Understanding of the anatomy and physiology of the vocal folds, availability of better diagnostic tools and precise instruments has spurred the development of newer techniques for the management of benign lesions arising in the vocal folds. As the propensity of the superficial lamina propria to regenerate is minimal, it is of paramount importance to maximally preserve it. Microflap surgery of the vocal folds is based on this principle.

There exists a dichotomy in opinion regarding the role of subepithelial infiltration in microflap surgery; the disadvantages cited being possible confusion of the surgical plane following infiltration and hydrodissection of the normal basement membrane from the superficial layer of the lamina propria. A prospective study was therefore carried out in 30 cases of benign glottic lesions and microflap surgery was performed with and without infiltration in similar pathologic lesions. The vocal outcomes i.e. fundamental frequency, jitter, shimmer and maximum phonation time were audited. The advantages of this technique with a review of the literature are discussed.

Thin films of Ba1-x SrxTiO3 (BST) are being actively investigated for applications in dynamic random access memories (DRAM) because of their properties such as high dielectric constant, low leakage current, and low fatigue. Several approaches have been used to improve the properties of thin films such as doping with aliovalent dopants, graded compositions, and layered structures. We have found that interposing layers of an electronic insulator such as ZrO2 in between BST layers results in a significant reduction in the leakage current. In this paper the low temperature electrical properties of these multilayer structures are reported. The structures consist of alternate layers of Ba0.8Sr0.2TiO3 and ZrO2 deposited by a sol-gel process on platinized Si substrates. The thickness and the number of layers are varied while keeping the total thickness of the film constant. Multiple peaks in the dielectric constant vs temperature plots at all frequencies are observed in the multilayered films. The properties of the multilayer films are a complex function of the number of layers and their thicknesses. A structure with several thin layers of ZrO2 interposed between the BST layers produces smoother plots than a single layer of ZrO2 of same total thickness. This is attributed to more uniform distribution, as determined by XPS, of ZrO2 in the multilayer structure due to smaller diffusion distances.

The memory retention properties of Pt/YMnO3/Y2O3/Si capacitors were investigated for the application of ferroelectric gate transistors. The epitaxially grown Pt/YMnO3/Y2O3/Si capacitors showed ferroelectric type hysteresis loop on the capacitance-voltage properties. Although the retention time of the as-deposited capacitors was ∼103 s, it was prolonged up to 104 s when the leakage current density was reduced from 4×10-8 A/cm2 to 2×10-9 A/cm2 by the annealing under N2 ambience. To reveal the relationship between the retention time and leakage current, the leakage current mechanism was investigated comparing several conduction mechanisms. It was found that the dominant leakage mechanisms at high and low electric fields were Poole-Frenkel emission from the Y2O3 layer and ohmic conduction, respectively. This result indicates that the leakage current was limited by the Y2O3 layer at high electric field and was mainly dominated by the amount of defects in the YMnO3 layer at low electric field. From the pseudo isothermal capacitance transient spectroscopy (ICTS), it was determined that the trap density was in an order of 1015 cm-3. Since the variation of the leakage current by annealing was observed only in the low electric field region, it is suggested that the retention properties of the Pt/YMnO3/Y2O3/Si capacitors was influenced by the amount of defects in the YMnO3 layer.

Compositionally asymmetric tri-color superlattices (TCS) with a combination of BaTiO3/SrTiO3/CaTiO3 have been grown by pulsed laser deposition (PLD) on atomically-flat SrRuO3-covered (001) SrTiO3 substrates. Conducting SrRuO3 films with single-terrace steps that closely mimic those of the SrTiO3 substrate also were grown by PLD and serve as bottom electrodes. In order to achieve atomic control of each layer, we have calibrated precisely the number of laser pulses required to grow one unit-cell-thick layers (∼200 for a laser spot of 0.4 mm2). These conditions allowed recording of pronounced oscillations of the reflection high-energy electron diffraction (RHEED) specular spot intensity over the entire growth run - even for TCS layers totaling more than 1000 nm in total thickness.

The effect of thin Ti/PbZr0.4Ti0.6O3 seed layers on the properties of PbZr0.4Ti0.6O3 (PZT) capacitors has been investigated. The seed layer is based on a bi-layer of thin Ti and thin PZT with a total thickness ranging from 10 to 25 nm, which was deposited on Ir/Pt or Ir/IrO2/Pt by sputtering. After crystallization of the seed layers the main 130-nm-thick PZT film was deposited and crystallized. As a result, a highly preferred (111)-orientation of the PZT was obtained on a 10-nm-thick seed layer, where the peak intensity ratios of (111)/{100} and (111)/{110} are about 100 and 20, respectively. The 10-nm-thick seed forms a pyrochlore phase with a very smooth surface, where the formation of the pyrochlore phase is attributed to Pb diffusion, resulting in a Pb deficient stoichiometry. The seed layer transformed to the perovskite phase during the main PZT crystallization. It is shown that an IrO2 layer beneath the Pt can prevent Pt layer degradation related to the volume expansion due to the oxidation of Ir during the main PZT crystallization. Capacitors with the 10-nm-thick seed layer fabricated on the Ir/Pt and Ir/IrO2/Pt substrates showed typical 2 Pr values of 44.0 μC/cm2 and 41.2 μC/cm2, respectively. The voltage found for 90%-polarization saturation is about 3.0 V, and the capacitors are fatigue-free at least up to 1010 switching cycles.

The implementation of SiC based sensors and electronics for operation in chemically harsh, high temperature environments depends on understanding the SiO2/SiC interface in field effect devices. We have developed a technique to fabricate wedge polished samples (angle ∼ 1×10−4 rad) that provides access to the SiO2/SiC interface via a surface sensitive probe such as xray photoelectron spectroscopy (XPS). Lateral scanning along the wedge is equivalent to depth profiling. Spatially resolved XPS images of the O 1s and Si 2p core levels were obtained of the interfacial region. Samples consist of device-quality thermally grown oxides on 4H-SiC single crystal substrates. The C 1s spectrum suggests the presence of a graphitic layer on the nominally bare SiC surface following thermal oxidation.