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Introduction: Acute aortic syndrome (AAS) is a time sensitive aortic catastrophe that is often misdiagnosed. There are currently no Canadian guidelines to aid in diagnosis. Our goal was to adapt the existing American Heart Association (AHA) and European Society of Cardiology (ESC) diagnostic algorithms for AAS into a Canadian evidence based best practices algorithm targeted for emergency medicine physicians. Methods: We chose to adapt existing high-quality clinical practice guidelines (CPG) previously developed by the AHA/ESC using the GRADE ADOLOPMENT approach. We created a National Advisory Committee consisting of 21 members from across Canada including academic, community and remote/rural emergency physicians/nurses, cardiothoracic and cardiovascular surgeons, cardiac anesthesiologists, critical care physicians, cardiologist, radiologists and patient representatives. The Advisory Committee communicated through multiple teleconference meetings, emails and a one-day in person meeting. The panel prioritized questions and outcomes, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. The algorithm was prepared and revised through feedback and discussions and through an iterative process until consensus was achieved. Results: The diagnostic algorithm is comprised of an updated pre test probability assessment tool with further testing recommendations based on risk level. The updated tool incorporates likelihood of an alternative diagnosis and point of care ultrasound. The final best practice diagnostic algorithm defined risk levels as Low (0.5% no further testing), Moderate (0.6-5% further testing required) and High ( >5% computed tomography, magnetic resonance imaging, trans esophageal echocardiography). During the consensus and feedback processes, we addressed a number of issues and concerns. D-dimer can be used to reduce probability of AAS in an intermediate risk group, but should not be used in a low or high-risk group. Ultrasound was incorporated as a bedside clinical examination option in pre test probability assessment for aortic insufficiency, abdominal/thoracic aortic aneurysms. Conclusion: We have created the first Canadian best practice diagnostic algorithm for AAS. We hope this diagnostic algorithm will standardize and improve diagnosis of AAS in all emergency departments across Canada.
Perforations of the tympanic membrane are treated with various surgical techniques and materials. This study aimed to determine the efficacy of platelet-rich plasma during underlay myringoplasty.
The study included 40 patients. Autologous platelet-rich plasma was applied in-between temporalis fascia graft and tympanic membrane remnant during underlay myringoplasty in group 1 (n = 20). The outcome was evaluated after three months and compared with group 2 (n = 20), a control group that underwent routine underlay tympanoplasty.
After three months’ follow up, graft uptake was 95 per cent in group 1 and 85 per cent in group 2 (p < 0.03). Mean hearing threshold gain was 18.62 dB in group 1 and 13.15 dB in group 2. This difference was statistically significant (p < 0.01).
Platelet-rich plasma, with its ease of preparation technique, availability, low cost, autologous nature and good graft uptake rate, justifies its use in tympanoplasty type I procedures.
We present results of our studies for a sample of Galactic globular star clusters with the aim of deriving relative proper motions. We used CCD archival data observed with Wide Field Imager (WFI) mounted on ESO 2.2 m telescope at La Silla, Chile. Astrometric software designed by Anderson et al. is used to derive relative proper motions. The vector point diagrams show clear separation of field stars from the cluster stars. We used proper motions to determine membership probabilities and to produce color-magnitude diagrams with most probable cluster member stars. Our membership catalogue can be used to study the membership status of the peculiar stars including various variables reported in the literature.
We have made photometric observations of the galactic superluminal jet source GRS 1915+105 in the energy bands of 2-6 and 6-18 keV during 1997 June 12-29 and August 8-10. During our observations, different types of very intense, quasi-regular X-ray bursts have been observed from this source. We present here the light curves and the power density spectra of our observation of this source in its bright state.
We have made observations of the black hole binary Cyg X-1 with the Indian X-ray Astronomy Experiment (IXAE). Observations made with time resolution ranging from 0.4 ms to 1 s showed variations and flaring activity on sub-sec and longer time scales. Results on time variability on different time scales and flaring characteristics in the two states of Cyg X-1 are presented.
The choice of an appropriate cropping system is critical to maintaining or enhancing agricultural sustainability. Yield, profitability and water use efficiency are important factors for determining suitability of cropping systems in hot arid region. In a two-year field experiment (2009/10–2010/11) on loam sandy soils of Bikaner, India, the production potential, profitability and water use efficiency (WUE) of five cropping systems (groundnut–wheat, groundnut–isabgol, groundnut–chickpea, cluster bean–wheat and mung bean–wheat) each at six nutrient application rate (NAR) i.e. 0, 25, 50, 75, 100% recommended dose of N and P (NP) and 100% NP + S were evaluated. The cropping systems varied significantly in terms of productivity, profitability and WUEs. Averaged across nutrient application regimes, groundnut–wheat rotation gave 300–1620 kg ha−1 and 957–3365 kg ha−1 higher grain and biomass yields, respectively, than other cropping systems. The mean annual net returns were highest for the mung bean–wheat system, which returned 32–57% higher net return than other cropping systems. The mung bean–wheat and cluster bean–wheat systems had higher WUE in terms of yields than other cropping systems. The mung bean–wheat system recorded 35–63% higher WUE in monetary terms compared with other systems. Nutrients application improved yields, profit and WUEs of cropping systems. Averaged across years and cropping systems, the application of 100% NP improved grain yields, returns and WUE by 1.7, 3.9 and 1.6 times than no application of nutrients. The results suggest that the profitability and WUEs of crop production in this hot arid environment can be improved, compared with groundnut–wheat cropping, by substituting groundnut by mung bean and nutrients application.
Nb/MgO/Nb/Al2O3 multilayer stacks were prepared by MBE growth of Nb and MgO films on a (0112)A1203 sapphire substrate. Sequential deposition of Nb followed by MgO on the sapphire substrate resulted in three different interfaces: one between Nb deposited on sapphire as the substrate (the Nb1/Al2O3 interface), one between MgO deposited on Nb as the substrate (the MgO/Nb1 interface), and finally one between Nb deposited on MgO as the substrate (the Nb2/MgO interface). Cross-sectional TEM specimens from the multilayer were prepared and the various interfaces were investigated by high resolution electron microscopy (HREM). Orientation relationships between Nb1 and Al2O3 and also between MgO and Nb1 were determined and misfit dislocations, steps and facets at the Nb1/Al2O3 and MgO/Nb1 interfaces were analyzed. The HREM observations showed that an intterfacial phase forms at the Nb1/Al2O3 interface by a solid state reaction under electron beam irradiation.
MgO was deposited on different planes of sapphire substrates by Molecular Beam Epitaxy (MBE). Cross-sectional specimens from these systems were prepared and investigated by high resolution electron microscopy (HREM). Two different orientation relationships were obtained for MgO films deposited on the differently oriented sapphire substrate. Misfit dislocations at the interface in each case were analyzed. MgA12O4 (spinel) forms at the MgO/A12O3 interface by a solid state reaction under electron beam irradiation.
Size dependence of the low frequency vibrational spectra of ZnO nanocrystals prepared using chemical method has been investigated. Optical transmission spectra of the ZnO colloid solution exhibit a shift in the onset of the absorption band edge from 332 to 350 nm due to particle growth. X-ray diffraction analysis of the prepared ZnO nanocrystals exhibit peaks corresponding to the hexagonal wurtzite structure. Two peaks with unusually very high intensity were observed in the low frequency (∼ 10- 25 cm-1) Raman spectra of these nanocrystals. The peak position of these phonon modes shifted towards lower frequencies as the size of the nanocrystals increases and assigned to the confinement of acoustic phonons in ZnO nanocrystals.
Syntheses carried out on soluble polymers, such as polyethylene glycol (PEG), benefit the advantages of both solution-phase and solid-phase syntheses. The choice of the reaction solvent governs the polymer solubility. Synthetic steps are conducted under homogeneous conditions whereas purifications are performed by filtration after polymer precipitation. This alternative strategy, known as liquid-phase chemistry, has been investigated to prepare combinatorial libraries.
The fact that soluble polymer supported molecules are directly amenable to standard spectroscopic methods, including NMR (1H, 13C) and ESI or MALDI mass spectrometry (ElectroSpray and Matrix Assisted Laser Desorption Ionization) allows to perform to in situ reaction monitoring without the need to release the compound from the polymeric support.
We report a general methodology to characterize step by step soluble polymer supported organic molecules by MALDI and ESI mass spectrometry. High throughput analyses were targeted to fullfil combinatorial chemistry requirements. Data acquisition and interpretation were automated through the design of specific experimental protocols and a data managment software. MALDI mass spectrometry was appropriate to analyze pure supported molecules whereas ESI mass spectrometry coupled to liquid chromatography was required to unravel PEG mixtures.
Field experiments were conducted for the three consecutive cropping seasons of 2003–05, 2004–06 and 2005–07 at the Indian Institute of Sugarcane Research, Lucknow, India, to explore the feasibility of planting sugarcane in autumn as a relay intercrop in standing rice. The cropping systems evaluated were: i) rice-potato-spring sugarcane; ii) rice + autumn sugarcane (planted as a relay intercrop in every sixth row devoid (skipped) of transplanted rice + potato after rice; iii) rice-autumn sugarcane (planted without preparatory tillage) + potato; and iv) rice-autumn sugarcane (planted with preparatory tillage) + potato. In each case, sugarcane was planted in rows 90 cm apart. Rice was transplanted in rows at 20-cm row spacing when followed by potato or sugarcane, but at 18-cm row spacing when intended for sugarcane planting as a relay intercrop in late September. The germination (60.4%) of cane buds, tillers (323 000 ha−1) and number (149 000 ha−1), length (225 cm), girth (2.44 cm) and weight (747 g) of millable canes were markedly better when autumn sugarcane was planted with rice as a relay intercrop in comparison to other cropping systems. Similarly, this cropping system produced the maximum cane (111.4 t ha−1) and sugar (13.2 t ha−1) along with sugarcane equivalent yield (216.4 t ha−1). In turn, relay intercropping system with maximum cane production efficiency of 420 kg ha−1day−1 fetched the highest economic returns (Rs. 258 ha−1day−1) and benefit:cost ratio (1.5). Compared with the rice-potato-spring sugarcane cropping system, the relay intercrop of autumn sugarcane in standing rice produced 35.4% more cane and 38.3% more sugar with 24.1% higher returns besides 79.1% energy saving. This practice will not only benefit cane growers and sugar mill owners in tropical and sub-tropical India, but also in other parts of the world where rice and sugarcane are extensively cultivated.
On-farm nutrient management practices were evaluated in the irrigated rice-wheat cropping system (RWCS) in northwestern India. Large farmers used comparatively higher doses of nutrients than small and medium farmers for both rice and wheat crops. On average, a field is treated with organic manure after every 15 years for rice and 53 years for wheat. Nitrogen use was generally more than the recommended dose for both crops. Phosphorus use in wheat was nearly as per recommendation, while in rice it was below the recommended dose. Potassium use was almost nil; however, the use of Zn (particularly in rice) is becoming common. Use of biofertilizers was negligible. Overall, farmers applied higher doses of organic manures, K, Zn and biofertilizers in rice than wheat, and there was increasing trend in their use with increase in the size of land holdings. Grain yield increased significantly with increase in the size of land holding in rice but remained almost same in wheat. This study generated comprehensive data on nutrient use pattern in the RWCS, thus providing necessary input to researchers, planners and developmental agencies who wish to enhance food security.
In the hilly areas of eastern Gujarat, western Madhya Pradesh and southern Rajasthan, in western India, farmers are very resource-poor and cultivate small and fragmented land holdings. Maize is their main rainy season (kharif) cereal and it is grown as a rainfed crop in low-fertility fields, often on sloping land that is vulnerable to soil erosion. Its productivity is very low, averaging below 1 t ha−1. New farm technologies to increase this productivity have to be low cost to be attractive to farmers who have limited access to purchased inputs and few means to purchase them. From observations of local farming practices, intercropping of maize with legumes was identified as an attractive option because the only additional input needed is seed of the legume crop. Participatory research was conducted on intercropping of maize with improved varieties of horsegram (Macrotyloma uniflorum). Many farmers who tried this intercropping adopted it in subsequent years, while others preferred to grow the new horsegram varieties as a sole crop. Farmers reported that less weeding was required in the intercrop as the horsegram smothered weeds. All farmers used the dry stover from the horsegram as a fodder for their animals. Farmers used the whole seed as dal, which provided additional protein in their diet. Farmers also sold the grain, but it fetched a low price in the poorly developed market for horsegram. Previously intercropping had been tried with local landraces, but the acceptance of intercropping was higher with new varieties such as AK-42 that yielded over 60% more grain. Participatory trials in which only one entry was compared with the local variety did not show a difference between AK-21 and AK-42 as in all cases both were preferred over the local variety. When they were directly compared with each other, farmers' perceptions showed a significant preference for AK-42. Variety IVH-2 was found to be better than AK-42: it matured 15 days earlier, better matching the maturity of the maize, had superior grain quality and yielded about the same. The greater uptake of improved horsegram varieties for sole and intercropping is likely to be limited by the lack of seed supply.
The landraces of rice (Oryza sativa L.) possess wide diversity, which needs to be properly characterized for their use in genetic improvement. Replicated field studies were conducted in 1998, 1999 and 2000 at two sites in Nepal to determine diversity in 183 landraces of rice adapted to the lowlands and the hills in Nepal. Fourteen improved genotypes were also used for comparison. Thirteen agronomic traits were investigated. Shannon–Weaver diversity index (H) and Simpson's index of diversity (D) were estimated to determine the level of genetic richness among the landraces. The landraces differed significantly for all traits. Except for plant height and maturity, at least one of the landraces compared well with the performance of improved cultivars. A principal component analysis separated the lowland- and hill-adapted landraces into two broad groups.
Chickpea (Cicer arietinum L.) is an important crop for developed as well as underdeveloped countries, especially those in the Indian sub-continent that contribute more than 60% to both the global area and global production. The harsh environmental conditions under which chickpeas are generally grown impose restrictions on the expression of genetic yield potential. In the present study, a number of different breeding approaches for the development of genotypes possessing multiple resistances to different biotic and abiotic stresses, coupled with enhanced productivity are reported. In one study, 90 genetically diverse genotypes (35 medium-sized desi types, 35 bold-seeded desi types, 10 medium-sized kabuli types and 10 bold-seeded kabuli types) were tested in several locations in the 2000–2002 seasons, under rainfed (dryland) conditions and with supplemental irrigation. The bold-seeded desi genotypes gave superior performance in the rainfed environment, while the bold-seeded kabuli genotypes outyielded the other cultivars under supplemental irrigation. From crosses between accessions from geographically diverse sources, crosses between lines carrying multiple disease resistances, and crosses between the cultivated chickpea and the wild species, C. reticulatum, 23 selections were tested for yield and resistance to multiple stresses at various locations in northern and central India. From the crosses between geographically diverse parents, six high-yielding kabuli genotypes with wide adaptation and drought tolerance were identified. Pyramiding genes for multiple resistances proved useful in identifying eight lines possessing multiple disease resistance. Introgressing wild genes generated nine genotypes with high yield potential, resistance to soil-borne diseases and adaptation to water-limited environments. We conclude that high productivity, multiple resistance and wide adaptability can be achieved simultaneously by using potentially complementary approaches.
Intercropping of pearl millet (Pennisetum glaucum) with clusterbean (Cyamopsis tetragonoloba) is a common practice in the arid zone of northwestern India. Field experiments were conducted for two years to examine the performance of two contrasting genotypes of each of these crops grown both as sole crops and as intercrops using all possible genotypic combinations of the pearl millet with the clusterbean. The seed yields of both crops were always lower in intercropping than in sole cropping, though the degree of reduction in the seed yield of each intercrop component was influenced greatly by the genotype of its companion crop. The seed yield of both clusterbean genotypes was reduced more when intercropped with the tall and late-maturing pearl millet, MH 179, than with the medium-statured and early-maturing HHB 67. On the other hand, the two clusterbean cultivars had similar effects on intercropped pearl millet. As a result, the highest land equivalent ratios (LERs) were obtained with intercrops containing pearl millet HHB 67 rather than MH 179, while the genotype of clusterbean had little overall effect on LER. The results obtained are discussed in the context of developing cultivars for intercropping.
The response of late-sown mustard (Brassica juncea L.) to four rates of irrigation (ratio of irrigation depth to cumulative pan evaporation, ID:CPE = 0·2, 0·4, 0·6 and 0·8) and nitrogen (0, 30, 60 and 90 kg/ha) was investigated at Haryana Agricultural University, India, in the winter seasons of 1986/87 and 1987/88. Increases in the amounts of water and N fertilizer applied increased leaf water potential, stomatal conductance, light absorption, leaf area index, seed yield and evapotranspiration and decreased canopy temperature. Water-use efficiency was highest for the 0·4 ID:CPE irrigation treatment in both seasons, and for the 60 kg N/ha N treatment in 1986/87 and the 90 kg N/ha treatment in 1987/88. The combination of 0·6 ID:CPE with 60 kg N/ha gave a significantly higher seed yield than lower rates and equalled that from the highest irrigation and N treatment combinations. The amount of water used by the mustard crop decreased with increasing soil depth irrespective of treatment. In the deeper soil layers, the percentage of total moisture use was greater under less irrigated than under more frequently irrigated plots. Leaf area index showed a significant positive linear relationship with evapotranspiration and light absorption and a negative linear relationship with canopy temperature. Seed yield was linearly related to leaf area index and light absorption coefficient.