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The effect of cooling rate on the phase composition of gas atomized Raney type catalysts was studied using the Ni-75 at.% Al composition. The resulting particles were sieved into 3 standard size fractions and analysed using XRD with Rietveld refinement: as expected the three phases, Al₃Ni₂, Al₃Ni, and Al-Al₃Ni eutectic were identified. Differing phase compositions in the 3 size ranges were identified offering a possible explanation for varying catalytic activity with cooling rate, the higher cooling rates experienced by the smaller droplets allow less time for the peritectic conversion of Al₃Ni₂ to Al₃Ni to proceed. This in turn results in a more Al-rich residual liquid, increasing the volume fraction of eutectic. This was further confirmed when analysing the microstructure using SEM backscatter imaging. Al₃Ni₂ was found to be encased in a shell of Al₃Ni characteristic of peritectic reactions. The remainder of the alloy was found to consist of Al-Al₃Ni eutectic. The SEM backscatter imaging also indicated that the larger particles displayed and a more globular structure than smaller particles. Similar Raney type Ni-75 at.% Al doped with 1.5 at.% Cr were synthesised using the same method and sieved into the same 3 standard size fractions. It was found that the Cr doped alloys exhibited a more dendritic character than the undoped samples in the corresponding size fraction, although the material still displayed an increasingly dendritic character with increasing cooling rate. The phase composition found by Rietveld refinement also followed a similar trend to the undoped samples with decreasing amounts of Al₃Ni formed at the higher cooling rates. However, significant amounts of an additional phase, Al₁₃Cr₂, were also observed. Rietveld refinement found that a larger amount of Al₁₃Cr₂ was present than could be accounted for by the addition of 1.5 at.% Cr . This can be explained by the substitution of Ni onto the Cr lattice, as confirmed by Rietveld refinement. Al₁₃Cr₂ was found to be located mostly at the boundary of the Al₃Ni and Al-Al₃Ni eutectic phases during elemental mapping and quantitative image analysis of backscattered electron micrographs. This indicates that precipitation of Al₁₃Cr₂ is towards the end of the solidification process. The relatively large amounts of the Al-rich Al₁₃Cr₂ may explain the enhanced catalytic activity observed following leaching of Cr-doped Raney catalysts.
Unavailability of irrigation water for early sowing has remained a constant problem in cold arid deserts of Ladakh. In order to get a solution to this problem, a 2-yr farmers’ participatory research trial with best bet agronomic management on artificial glacier water harvesting technology was conducted. The technology involves collecting water from natural glaciers that melt during late December. The water is diverted toward a shed constructed with stone embankments set up at regular intervals. The area is chosen where there is minimum interference of solar radiation, generally between two mountain slopes or ridge that is on the leeward side. The melted water is that melts from the natural glacier impeded by the embankments and get frozen here. This frozen water starts melting in late March and is used for both pre sowing and initial crop water requirement. It also ensures early sowing of wheat by creating additional 45-day window which leads to introduction of long- and medium-duration wheat varieties to replace decades old locally grown short-duration varieties. The work was initiated with a benchmark survey of 100 farmers to get an understanding of present irrigation scenario, crop management practices and date of sowing. Data from 99 farmer participating trial of wheat conducted after or from bench mark survey clearly indicated that the effect of water shortage can be seen on yield and yield attributing characters due to unavailability of pre sowing irrigation and water requirement at imperative growth stages and may also lead to terminal heat stress in wheat crop. Out of total number of irrigations applied, initial two irrigations can be compensated by artificial glacier water harvesting technique, leading to a revolution in the agriculture scenario of the tribal population by introduction of long- and medium-duration wheat varieties in cold arid desert of Ladakh for the very first time. It was observed that wheat seeding done in first fortnight of April gave better yields in comparison to late seeded wheat. Moreover, the long-duration varieties (LDVs) or medium-duration varieties (MDVs) sown under late condition gave better yield in comparison to locally grown short-duration varieties sown at same time. Yield potential of LDVs and MDVs of wheat under late sowing was found quite low in comparison to early-sown wheat, still when compared with the performance of locally grown wheat the yields were more even if the local varieties were sown early. The outcome of this study will help the farmers of tribal, cold arid community in harvesting better wheat yields by timely sowing of the wheat crop accompanied with better bet agronomic management practices. Government initiative is further required to ensure better outreach of complete crop management strategies to the tribal farming community of the region in order to ensure food security and improve their socioeconomic status.
Spatial confinement effects on plasma parameters and surface morphology of laser-ablated Mg are studied by introducing a metallic blocker as well as argon (Ar) gas at different pressures. Nd: YAG laser at various fluences ranging from 7 to 28 J/cm2 was employed to generate Mg plasma. Confinement effects offered by metallic blocker are investigated by placing the blocker at different distances of 6, 8, and 10 mm from the target surface; whereas spatial confinement offered by environmental gas is explored under four different pressures of 5, 10, 20, and 50 Torr. Laser-induced breakdown spectroscopy analysis revealed that both plasma parameters, that is, excitation temperature and electron number density initially are strongly dependent upon both pressures of environmental gases and distances of blockers. The maximum electron temperature of Mg plasma is achieved at Ar gas pressure of 20 Torr, whereas maximum electron number density is achieved at 50 Torr. It is also observed that spatial confinement offered by metallic blocker is responsible for the significant enhancement of both electron temperature and electron number density of Mg plasma. Maximum values of electron temperature and electron number density without blocker are 8335 K and 2.4 × 1016 cm−3, respectively, whereas these values are enhanced to 12,200 K and 4 × 1016 cm−3 in the presence of blocker. Physical mechanisms responsible for the enhancement of Mg plasma parameters are plasma compression, confinement and pronounced collisional excitations due to reflection of shock waves. Scanning electron microscope analysis was performed to explore the surface morphology of laser-ablated Mg. It reveals the formation of ripples and channels that become more distinct in the presence of blocker due to plasma confinement. The optimum combination of blocker distance, fluence and Ar pressure can identify the suitable conditions for defining the role of plasma parameters for surface structuring.
The poultry industry is currently facing a serious problem of controlling coccidiosis, owing to the development of drug resistance against commonly available anticoccidials. Furthermore, an increasing demand in the consumers for drug residue free poultry and poultry products has led to the development of alternative strategies for the treatment and control of avian coccidiosis. In response to the invasion of Eimeria species in coccidiosis, oxidative stress is created by host cellular response which imparts pathology to the host tissue besides damaging the parasite. Hence, in order to alleviate the damage caused by oxidative stress during coccidiosis, the use of essential oils (EOs) rich in antioxidant compounds is being considered as an appealing approach. However, results are very divergent and often not as satisfactory as expected. Essential oils, as natural products, obtained from aromatic plants have the potential to serve as an alternate to anticoccidials. The present work aims to review the current state of knowledge, informative collection of results obtained over the years and to attain a critical decision in aspects of the use of EOs as anticoccidials.
To compare the skin-related complications of the traditional skin flap method with a linear incision method of implantation.
All cases of bone-anchored hearing aid surgery performed by a single surgeon (n = 117) were compared over two periods: 1999–2011, when the traditional method of skin flap and soft tissue removal was used (group 1; n = 86), and 2012–2013, when linear incision without soft tissue removal was used (group 2; n = 31). All patients were followed up for one year and complications were recorded for that period.
There were 21 (24.4 per cent) skin-related complications in group 1 (skin overgrowth = 12, wound infection = 8 and numbness = 1) and 3 (9.7 per cent) complications in group 2 (wound infection = 3). Analysis using independent t-tests showed the results to be significant (p < 0.05; 95 per cent confidence interval = 0.0800–0.4473).
The linear incision without soft tissue removal method for bone-anchored hearing aid implantation reduces skin complication rates.
Present paper addresses the numerical study of Sisko fluid model over stretching cylinder with variable thermal conductivity. The governing equations are simplified by incorporating the boundary layer approximations. After employing suitable similarity transformations partial differential equations are reduced to ordinary differential equations. To obtain numerical solution shooting method in conjunction with Runge-Kutta-Fehlberg method is used. For the analysis of model, variations due to different physical parameters involved in momentum and heat equations are reflected through graphs. Also, the effects of physical parameters on skin-friction coefficient and Nusselt number are represented through graphs as well as tables.
This study was conducted to improve wheat production under vegetative (early season) drought stress. Hydroprimed and osmoprimed (with CaCl2) seeds of wheat cultivars Lasani-2008 (LS-2008) and Triple Dwarf-1 (TD-1), were sown in 20 (narrow), 25 (medium), and 30 cm (wider) spaced rows. Crop was grown under well-watered conditions till physiological maturity or was subjected to drought stress (50% field capacity) during vegetative phase and then grown under well-watered conditions. Drought stress caused substantial reduction in grain and biological yields, related traits, harvest index (HI) and water use efficiency (WUE). Nonetheless, planting osmoprimed seeds in narrowly spaced rows significantly improved the grain yield, HI and WUE. However, wheat planted in wider rows had bold grains. Furthermore, wheat cultivar LS-2008 produced better yield, even under drought stress, than cultivar TD-1. Economic analysis indicated that planting osmoprimed seeds of wheat cultivar LS-2008 in narrowly spaced rows under early season drought yielded maximum economic benefits. In conclusion, planting osmoprimed seeds of cultivar LS-2008 in narrowly spaced rows is a good agronomic option to improve the wheat performance under early season drought stress.
The linear operator plays an important role in the computational process of Homotopy Analysis Method (HAM). In HAM frame any kind of linear operator can be chosen to develop a solution. Hence, it is easy to introduce the modified/physical parameter dependent linear operators. The effective use of these operators has been judged through solving fluid flow problems. Modification in linear operators affects the solution and improves the computational efficiency of HAM for larger values of parameters. The convergence rate of the solution is rapid and several times higher resulting in lesser computational time.
Children with obstructive sleep apnoea commonly undergo adenotonsillectomy as first-line surgical treatment. This paper aimed to investigate whether this intervention was associated with weight gain after surgery in the paediatric population with obstructive sleep apnoea.
Two independent researchers systematically reviewed the literature from 1995 to 2014 for studies on patients who underwent adenotonsillectomy with weight-based measurements before and after surgery. The databases used were Ovid Medline, Embase and PubMed.
Six papers satisfied all inclusion criteria. Four of these papers showed a significant weight increase and the others did not. The only high quality, randomised, controlled trial showed a significant increase of weight gain at seven months follow up, even in patients who were already overweight before their surgery.
The current evidence points towards an association between adenotonsillectomy and weight gain in patients with obstructive sleep apnoea in the short term.
This paper, a report by the Clinical Governance and Audit Committee of the Scottish Otolaryngological Society, presents a consensus view of the minimal requirements for ENT clinics in National Health Service hospitals.
Results and conclusion:
The provision of adequate equipment and staff has gained increasing importance as the vast majority of ENT procedures can be safely performed in the out-patient or office setting.
In this study, we compared the weed emergence, water input, water saving, water productivity, panicle sterility, yield outputs and economic returns of transplanting with alternate wetting and drying (TRAWD) and dry direct seeding (DSR) with transplanting under continuous flooding (TRCF) using three fine-grain rice cultivars: Super Basmati; Basmati 2000; and Shaheen Basmati. Higher weed infestation was recorded in DSR than in TRCF and TRAWD. Raising rice as TRAWD and DSR had considerable water savings but a lower grain yield than TRCF. High panicle sterility was primarily responsible for low grain yield in TRAWD and DSR systems. Nonetheless, water productivity was better in DSR and TRAWD than TRCF. Shaheen Basmati in the DSR system and Basmati 2000 in TRCF fetched the highest economic returns during 2008 and 2009, respectively. In conclusion, fine-grain rice cultivars can be grown in water-saving production systems (e.g. TRAWD and DSR); however, these water-saving production systems might incur a yield penalty.
We present the results of a numerical simulation of the corona and wind structure of the Sun-like exoplanet-host GJ 3021 using a global magnetohydrodynamic (MHD) model. The simulation is driven by the radial component of the surface magnetic field recovered with the Zeeman Doppler Imaging (ZDI) technique. We consider two different ZDI input maps, which have similar large-scale structures but different spatial resolutions and field strengths. These maps arise from different but comparable models used to fit the observed circularly polarised spectra of the star. Our simulations show that the structure of the inner corona is consistent among the considered cases. Larger discrepancies are found in the wind structure, in particular in the radial wind speed and the Alfvén surface topology. These elements can have a significant impact on the mass loss and angular momentum loss predicted for this system and in other studies based on this numerical data-driven approach.
This study aimed to compare the outcomes of two frequently employed interventions for the management of tinnitus: tinnitus retraining therapy and cognitive behavioural therapy.
A systematic review of literature published up to and including February 2013 was performed. Only randomised control trials and studies involving only human participants were included.
Nine high-quality studies evaluating the efficacy of tinnitus retraining therapy and cognitive behavioural therapy were identified. Of these, eight assessed cognitive behavioural therapy relative to a no-treatment control and one compared tinnitus retraining therapy to tinnitus masking therapy. Each study used a variety of standardised and validated questionnaires. Outcome measures were heterogeneous, but both therapies resulted in significant improvements in quality of life scores. Depression scores improved with cognitive behavioural therapy.
Both cognitive behavioural therapy and tinnitus retraining therapy are effective for tinnitus, with neither therapy being demonstrably superior. Further research using standardised, validated questionnaires is needed so that objective comparisons can be made.
This study describes the first large-scale serosurvey on West Nile virus (WNV) conducted in the equine population in Pakistan. Sera were collected from 449 equids from two provinces of Pakistan during 2012–2013. Equine serum samples were screened using a commercial ELISA kit detecting antibodies against WNV and related flaviviruses. ELISA-positive samples were further investigated using virus-specific microneutralization tests (MNTs) to identify infections with Japanese encephalitis virus (JEV), WNV and tick-borne encephalitis virus (TBEV). Anti-WNV antibodies were detected in 292 samples by ELISA (seroprevalence 65·0%) and WNV infections were confirmed in 249 animals by MNT. However, there was no animal found infected by JEV or TBEV. The detection of WNV-seropositive equines in Pakistan strongly suggests a widespread circulation of WNV in Pakistan.
Imprinting is a well-established technique to induce recognition features in both organic and inorganic materials for a variety of target analytes. In this study, ion imprinted polysiloxanes with varying percentage of coupling agent i.e. 3-chloro propyl trimethoxy silane (CPTM) were synthesized by sol-gel method for imprinting of Cr3+. The imprinting of Cr3+ in cross-linked siloxane network was investigated by FT-IR which indicates the metal ion is coordinated with oxygen atoms of polysiloxanes. SEM images revealed that imprinted polysiloxanes possess uniform particles of submicron size. It was experienced that by increasing the concentration of CPTM up to 10% (v/v) substantially improves the binding capacity of polysiloxanes which allows us to recognized Cr3+ down to 50µg/L. Furthermore, the selectivity of Cr3+-imprinted polysiloxanes was evaluated by treating them with other competing metal ions of same concentration i.e. Cr6+, Pb2+ and Ni2+. In this regard, polysiloxanes showed much higher binding for imprint ion i.e. Cr3+ in comparison to above mentioned metal ions. Finally, the regenerated polysiloxanes were studied in order to reuse them thus, developing cost effective biomimetic sensor coatings.
Hydropericardium syndrome (HPS) is a fatal disease of broiler chickens causing high mortality and heavy economic losses in various countries. More than 100 million birds have been affected by this destructive disease in less than two years worldwide. As it is a viral disease, the only solution is to vaccinate chickens. Different types of vaccines are being used against this disease in different areas of the world. Liver organ inactivated vaccines are more extensively used to control the disease initially. These vaccines have many drawbacks regarding their dose, un-predictable immune response and secondary bacterial infections. Following this, oil adjuvant vaccine was used to control the disease, however the handling stress and the formation of granuloma at the site of injection remains a problem. Consequently there is a need for cell culture adapted and attenuated vaccines, which can be administered through oral routes. A chicken embryo-adapted inactivated vaccine has shown good results but requires a continuous supply of specific, pathogen-free chicken embryos and a continuous life killing process. The continuous cell lines are a more promising solution for the production of cell culture-adapted and attenuated vaccines, which are safer, more economical and easy to administer. The following review discusses the development of modern HPS vaccines.
The association between eustachian tube dysfunction and middle-ear effusion is well established. Studies have also demonstrated pathological changes affecting the middle-ear mucosa associated with chronic sinonasal inflammation. No previous studies have evaluated symptoms related to sinonasal inflammatory disease in different ear diseases.
To assess the presence of sinonasal symptoms in ear diseases using the Dundee Rhinogram.
Data were collected prospectively in the period February–October 2011. Sinonasal symptoms were graded using the Dundee Rhinogram. Student's t-test analyses were performed to identify any statistically significant associations.
In total, 164 patients were assessed. There was a statistically significant association between sinonasal symptoms and mucosal middle-ear diseases (p < 0.005). The mean sinonasal symptoms score for mucosal middle-ear disease patients was 5.94 (range, 0–32).
Assessment of sinonasal symptoms is paramount in patients presenting with an ear symptom; inflammatory sinonasal disease treatment may become necessary in the management of middle-ear mucosal disease for better patient outcome.
Spectropolarimetric observations combined with tomographic imaging techniques have revealed that all pre-main sequence (PMS) stars host multipolar magnetic fields, ranging from strong and globally axisymmetric with ≳kilo-Gauss dipole components, to complex and non-axisymmetric with weak dipole components (≲0.1 kG). Many host dominantly octupolar large-scale fields. We argue that the large-scale magnetic properties of a PMS star are related to its location in the Hertzsprung-Russell diagram. This conference paper is a synopsis of Gregory et al. (2012), updated to include the latest results from magnetic mapping studies of PMS stars.