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• Optimum rice transplanting date in EIGP to achieve high yield with low risk is up to 2 August for long duration variety and is up to 16 August for short duration variety. • Late transplanting with old seedlings under farmer practice lead to low rice yields due to high drought risk but supplemental irrigation or short duration variety reduced the drought risk. • Transplanting of appropriate aged seedling at onset of monsoon yields 1.8 t ha−1 as compared to farmer practice. • There is high probability to meet required soil moisture conditions for DSR sowing during early June. • Supplemental irrigation for DSR crop establishment and to meet crop demands during dry periods can result in 5.8 t ha−1 in May and June sowings. Rice productivity in Eastern Indo-Gangetic plains (EIGP) is extremely low, in part due to the prevailing practice of cultivating long-duration transplanted rice under rainfed conditions which leads to water stress and significant yield losses in many seasons. Rice establishment alternatives such as direct seeded rice (DSR) require less water at planting but also are accompanied by climate risks that constrain adoption. For both conventional transplanted and DSR systems, successfully addressing climate-based production risks may provide a strong basis for sustainable rice intensification in EIGP. In this ex ante study of rice yield and yield variability, the APSIM cropping system model was used to evaluate the efficacy of risk-reducing management practices in both transplanted and DSR systems. Simulations were conducted with 44 years (1970–2013) of historical weather data from central Bihar, India. Results confirm that the prevailing farmer practice of transplanting long-duration cultivars under rainfed conditions (fTR) often results in delayed transplanting and the use of older seedlings, leading to low (median 1.6 t ha−1) and variable (Standard deviation (SD) 2.1 t ha−1) rice yields. To improve the fTR system, simulations suggest that adoption of medium-duration hybrid rice (3.2 t ha−1), provision of supplemental post-establishment irrigation (3.2 t ha−1), or transplanting appropriately aged seedlings (3.4 t ha −1) can double yields as single interventions while, in the case of supplemental irrigation, significantly reducing inter-annual production variability. Additional gains are achievable when interventions are layered: supplemental irrigation paired with medium-duration hybrids increased median rice yields to 4.6 t ha−1 with much lower variability (SD 1.0 t ha−1). In these improved systems where irrigation is used to transplant the crop, simulations revealed the importance of timely planting: high and stable yields are achievable for long-duration cultivars when transplanting is completed by 2 August with this window of opportunity extending to 16 August for medium-duration hybrids. In rainfed DSR systems, the potential pay-offs from single interventions were even higher with medium-duration hybrids resulting in a median yield of 4.5 t ha-1 against 1.8 t ha−1 with long-duration cultivars. For irrigated DSR systems, an optimum sowing window of early to mid-June was identified which resulted in higher and more stable yields with lower water requirements. Simulation results suggest several risk-reducing intensification pathways that can be selectively matched to farmer risk preferences and investment capabilities within the target region in EIGP. [ABSTRACT FROM AUTHOR]

The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together. [ABSTRACT FROM PUBLISHER]

The central mid-hills region of Nepal is characterized by rainfed production systems where maize ( Zea mays ) is the principal crop during the monsoon ( kharif ) season. In general, maize yields in the hills are judged to be intractably low and few efforts have systematically assessed either the water-limited productivity potential or identified sensible entry points toward sustainable intensification that can be selectively matched to the needs and constraints faced by different types of farmers. This study combines field surveys, on-farm field experiments, and simulation modeling (DSSAT) to explore opportunities for closing maize yield gaps in these ecologies. Among surveyed households, the mean grain yield of maize under current farmer practice was 2.0 t ha −1 whereas good agronomic practices increased maize yields up to 6.5 t ha −1 (i.e. exploitable yield gap of 4.5 t ha −1 ). Recognizing that farmers rarely adopt full technology packages, the value of single agronomic interventions was also explored with all other management factors maintained as per prevailing farmer practice. Averaged across sites and two seasons, non-limiting fertilizer rates (175:60:60 kg NPK ha −1 ) increased grain yields by 1.8 t ha −1 followed by the use of hybrids (1.4 t ha −1 ), higher plant population (0.9 t ha −1 ), and improved weed control (0.9 t ha −1 ). These results were also reflected in changes to the economic performance of the system with gross margins increasing from a ‘farmer practice’ base of $202 ha −1 (B:C = 1.86) to $339 ha −1 (B:C = 2.14) with hybrid adoption, $454 ha −1 (B:C = 2.88) with higher plant population, $646 ha −1 (B:C = 2.52) with non-limiting fertilizer, and $611 ha −1 (B:C = 3.37) with careful weed control. Further gains in profitability were achieved with layered agronomic interventions, which increased gross margins to $857 and $763 ha −1 (B:C = 2.95 in both) in conventional tillage (CT) and minimum (strip tillage; ST) systems, respectively. Divergence between grain yield gains and economic performance criteria highlights the importance of considering both perspectives. For resource-poor households, maintaining optimal plant population can increase B:C by more than 50% with small investments ($7 ha −1 ). Simulation results also suggest that additional potential productivity advantages are achievable with timely planting (e.g. 19% higher mean yield for short duration hybrid with less inter-annual variability). Cultivation of longer duration hybrids can also increase yield potential over their shorter duration alternatives, although trade-offs with yield potential of the second crop in the rotation must be considered. These results highlight several pathways toward intensification in the hills of Nepal that have varying investment requirements, inferred risks, and implications for the different dimensions of sustainability and food security. [ABSTRACT FROM AUTHOR]

This study describes SNOW-WEB, a distributed system of atmospheric sensors, which is cost-effective and can be efficiently deployed in Antarctica. The system supports traditional atmospheric sensors and has built-in redundancy as many units can be deployed in a relatively small area for a similar cost to one conventional weather station. Furthermore, each unit is equipped with wireless mesh-networking capabilities and so is able to share information with those units in its direct vicinity. This allows for the ferrying of collected information to a manned observation station and hence the ability to monitor data in real-time. GPS hardware installed on each unit also allows for high-resolution glacier or ice shelf tracking. As a testing study, eighteen such weather stations were deployed in the vicinity of Scott Base, Ross Island, Antarctica over the 2011/12 summer season. This paper reports on the successful development and deployment of the system, results from the testing period and challenges encountered during the experiment. Collected data is validated against automatic weather stations already operating in the region and an intercomparison is performed between SNOW-WEB data and forecast output from the Antarctic Mesoscale Prediction System. A high degree of agreement is found between data sources. We conclude that SNOW-WEB data is suitable for use in studies of mesoscale meteorology. [ABSTRACT FROM AUTHOR]

Abstract: For more than a decade, the System of Rice Intensification (SRI) has been vigorously promoted as a method for substantially improving the yield performance of conventional rice agriculture through a set of synergistic management principles that are purported to be accessible to poorer farmers and better for the environment. To evaluate the empirical basis for claims that SRI increases the yield ceiling for rice (i.e. the physiological yield potential), McDonald et al. [McDonald, A.J., Hobbs, P.R., Riha, S.J., 2006. Does the System of Rice Intensification outperform conventional best management? A synopsis of the empirical record. Field Crops Res. 96, 31–36] conducted a retrospective analysis of field experiments that had side-by-side yield comparisons of SRI and current best management practices (BMPs). In addition to studies from Madagascar where SRI was first conceived, 35 site-years of data were compiled from nine different Asian countries. Aside from one set of experiments in Madagascar where SRI more than doubled rice grain productivity with respect to BMPs (140–245% increase), we found no evidence of a yield advantage of this magnitude elsewhere. In 24 of 35 site-years, SRI yields were less than those attained with BMPs and in no case did the SRI yield exceed BMPs by more than 22%. Uphoff et al. [Uphoff, N., Kassam, A., Stoop, W., 2008. A critical assessment of a desk study comparing crop production systems: the example of the ‘system of rice intensification’ vs. ‘best management practice.’ Field Crop Res. 108 (1), 109–114] contest these findings with criticisms of our methodology and, more importantly, contend that key evidence demonstrating yield advantages for SRI over BMPs was not considered in our analysis. The assertion of key evidence that is at odds with our conclusions is false, as we detail in this response. Beyond Madagascar, there is still no empirical evidence that SRI has a unique yield advantage over current BMPs for rice. Then and now, our original article [McDonald, A.J., Hobbs, P.R., Riha, S.J., 2006. Does the System of Rice Intensification outperform conventional best management? A synopsis of the empirical record. Field Crops Res. 96, 31–36] accurately characterizes the global experience with the System of Rice Intensification. [Copyright &y& Elsevier]

Abstract: Degraded soil physical conditions from puddled rice (Oryza sativa L.) have been associated with low wheat (Triticum aestivum L.) yields in the rice–wheat rotation. To assess wheat productivity responses to rice management alternatives at a site in Nepal, we compared the impact of six rice tillage (10cm surface tillage – T1, 50cm deep chisel – T2, deep chisel+moldboard plough – T3) and establishment method (soil puddling+transplanting – TPR, direct seeding – DSR) combinations over two seasons (Y1, Y2). While significant soil physical differences were documented among the treatments during the rice season, we found little evidence that deep tillage or direct seeding for rice improves wheat performance. Rice cultural practices had no influence on the dynamics of soil water acquisition or inferred patterns of wheat root development. Although aboveground biomass production was similar, water acquisition, plant morphology, and yield were notably different between the first and second years. The Y1 crop had superior grain size (500-grain weight: 19.2g versus 17.8g) and tiller densities (382m−2 versus 320m−2), but grain productivity was 1.4tha−1 lower (3.0tha−1 versus 4.4tha−1) than in Y2. Comparatively poor performance in Y1 was reflected in the harvest index (0.27 versus 0.41) and density of spike-bearing tillers (188m−2 versus 247m−2). As an apparent consequence of pre-emergence irrigation, wheat in Y2 had higher root activities at depth with 11% of total water uptake derived from soil regions below 54cm under non-limiting moisture conditions. In contrast, the Y1 crop was first irrigated at 42 DAE and uptake below 54cm accounted for only 3% of the total under similar non-limiting conditions. Deeper rooting and a second irrigation at the end of tillering growth phase enabled the crop in Y2 to sustain exponential development for 25d during the floral initiation and spike growth stages, whereas the Y1 crop sustained exponential growth for only 14d. This difference was reflected in greater canopy height (94cm versus 80cm) and maximum leaf area (3.1 versus 2.7) in Y2. For allocating limited water resources, these findings suggest irrigation at planting to facilitate deep rooting followed by a second application at the end of the tillering growth phase to minimize water stress during grain sink formation. Optimized water management rather than modified rice cultural practices appears to be the best route for maximizing resource capture and wheat productivity at this site. [Copyright &y& Elsevier]

Abstract: Irrespective of its influence on agricultural productivity, the System of Rice Intensification (SRI) has certainly increased discussion over optimal rice cultivation practices, with many agricultural development practitioners at odds with a good deal of the established rice research community. To date, much of the debate over the putative benefits of SRI has been theoretical or speculative and has not persuaded adherents on either side. In aggregate, sufficient empirical data now exist to put SRI performance in a meaningful context by evaluating the productivity of SRI with respect to conventional best management practices (BMP). For this retrospective analysis, 40 site-years of SRI versus BMP comparisons were assembled into a common database. In addition to data from Madagascar where SRI was first conceived, findings from a broad geographic region were compiled including studies from Nepal, China, Thailand, Laos, India, Sri Lanka, Indonesia, Bangladesh, and the Philippines. Aside from one set of experiments in Madagascar where SRI more than doubled rice productivity with respect to BMP, we found no evidence of a systematic or even occasional yield advantage of this magnitude elsewhere. Indeed, none of the 35 other experimental records demonstrated yield increases that exceeded BMP by more than 22%. Excluding the Madagascar examples, the typical SRI outcome was negative, with 24 of 35 site-years demonstrating inferior yields to best management and a mean performance of −11%. With recognition that SRI yields in Madagascar are substantially beneath productivity levels predicted by bioclimatic factors, we find no evidence in the empirical record that SRI fundamentally changes the physiological yield potential of rice. Exceptional yield advantages from SRI – or some component(s) thereof – should not be projected beyond Madagascar. [Copyright &y& Elsevier]

Abstract: For maximizing water retention and attaining high yields, transplanting into puddled soil (TPR) is often considered the optimal method of rice (Orzya sativa L.) establishment. Alternative management techniques like direct seeding (DSR) and deep tillage have been proposed as mechanisms to improve soil physical properties for subsequent dry-season crops, but the risks to rice are uncertain. In this full factorial study on a valley terrace in Nepal, the influence of tillage (shallow—T1, deep chisel—T2, deep chisel+moldboard plough—T3) and establishment practice (TPR, DSR) on the field water balance and rice performance were evaluated in two adjacent landscape settings (terrace edge “upland”, central terrace “lowland”). Although deep tillage had only modest influences on seepage and percolation (SP) rates in both years (Y1, Y2), landscape placement and establishment practice had significant implications for the water balance (e.g. Y2 SP cmday−1: TPR-lowland=1.6, DSR-lowland=2.3, TPR-upland=4.1, DSR-upland=6.1). During low rainfall periods, however, soil water potential and drought vulnerability were governed solely by landscape placement. Despite water balance differences, there was little evidence that rice rooting behavior was substantially modified by landscape or establishment method. Weed biomass was higher in DSR, but was uncorrelated with water balance and productivity trends. In Y1, lower SP rates and more days with continuous flooding were positively associated with rice productivity. DSR yields were significantly lower than TPR in both landscape positions, with the lowland outperforming the upland (Y1 mtha−1: TPR-lowland=6.4, DSR-lowland=5.2, TPR-upland=5.7, DSR-upland=4.7). To determine if N dynamics were contributing to productivity differences, fertilizer nitrogen was increased from 120 to 150kgNha−1 in Y2. Results suggest that DSR performance is comparable – and landscape less important – if nitrogen is non-limiting (Y2 mtha−1: TPR-lowland=6.9, DSR-lowland=6.5, TPR-upland=7.0, DSR-upland=6.5); no aspect of the field water balance was associated with yield variability in Y2. For direct seeding in N-deficient farming systems, landscape criteria may prove useful for minimizing production risks by identifying field areas with lower SP rates. [Copyright &y& Elsevier]

Patient-controlled analgesia (PCA) is an analgesic technique originally used in adults but now with an established role in paediatric practice. It is well tolerated in children as young as 5 years and has uses in postoperative pain as well as burns, oncology and palliative care. The use of background infusions is more frequent in children and improves efficacy; however, it may increase the occurrence of adverse effects such as nausea and respiratory depression. Monitoring involves measurement of respiratory rate, level of sedation and oxygen saturation. Efficacy is assessed by self-reporting, visual analogue scales, faces pain scales and usage patterns. This is optimally performed both at rest and on movement. The selection of opioid used in PCA is perhaps less critical than the appropriate selection of parameters such as bolus dose, lockout and background infusion rate. Moreover, opioid choice may be based on adverse effect profile rather than efficacy. The concept of PCA continues to be developed in children, with patient-controlled epidural analgesia, subcutaneous PCA and intranasal PCA being recent extensions of the method. There may also be a role for patient-controlled sedation. PCA, when used with adequate monitoring, is a well tolerated technique with high patient and staff acceptance. It can now be regarded as a standard for the delivery of postoperative analgesia in children aged >5 years. [ABSTRACT FROM AUTHOR]

Investigates the impact of climate on weed competition applied to maize populations and Abutilon theophrasti interactions in New York. Reduction of maize populations after the emergence of weeds; Basis of economic threshold on the level of infestation; Assessment of the competitive status of maize crop by quantifying the weed population.

Focuses on the issues of medicine in Europe. Intervention against smoking by general practitioners; Medical confidentiality of child sexual abuse; Occurrence of delirium in patient treated with mianserin.

ABSTRACT Modified Gianturco arterial stents were placed in the iliac arteries of 3 non-atherogenic sheep. At three months after placement there was no evidence of migration of the stents or of excessive intimal overgrowth in relation to the stents. [ABSTRACT FROM AUTHOR]