7,081 research outputs found

    Rice research, technological progress, and impacts on the poor: the Bangladesh case (summary report)

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    "This case study builds on an ongoing large-scale quantitative research project undertaken by BIDS/IRRI since 1987 originally in 64 unions from 57 districts of the country. It adds a qualitative research component to examine the impact of modern rice varieties (MVs) on livelihoods in a structured sample of eight of these villages across a range of favorable and unfavorable contexts..... The quantitative research shows that for households with access to land there have been direct adoption impacts in the form of increased yields and higher profits. However, since rice now only represents around 20 percent of most households' overall income, nonagricultural income is found to have gained dramatically in importance for rural households. While the profitability has declined over time, rice contributes to improved food security and provides a “springboard” for both rich and poor farm households moving into nonfarm income generation and employment... The qualitative research component generally confirmed these general findings, highlighting other factors such as the improved status associated with fixed-rent tenancy and “contract” labor arrangements. The qualitative research also shows negative adoption impacts such as shrinking common property resources (wild fish, vegetables, etc., and declining soil fertility, both of which may increase the long-term vulnerability of the poor. It also throws light on the processes of technology dissemination.... It was found that the linking of qualitative and quantitative research methodologies was useful in (a) generating complementary data of different kinds on similar issues and (b) generating new data missed within a purely quantitative approach. The sustainable livelihoods framework was a useful, flexible tool for structuring the qualitative data collection and analysis. However, the research study as a whole was limited by the fact that the qualitative component was “bolted onto” a quantitative study already underway. Therefore the framework, and the various data collection methodologies, were not systematically integrated across both components of the study. In conclusion, future agricultural research on rice may need to further address the question of MV adoption potential on risk-prone lands, the relevance of existing technology dissemination systems, the relationship between MV adoption and crop diversification, and the challenges of more sustainable crop management techniques." Authors' AbstractRice Bangladesh,

    Scalable solid-state quantum processor using subradiant two-atom states

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    We propose a realization of a scalable, high-performance quantum processor whose qubits are represented by the ground and subradiant states of effective dimers formed by pairs of two-level systems coupled by resonant dipole-dipole interaction. The dimers are implanted in low-temperature solid host material at controllable nanoscale separations. The two-qubit entanglement either relies on the coherent excitation exchange between the dimers or is mediated by external laser fields.Comment: 4 pages, 3 figure

    Stereoselective Syntheses of 3’-Hydroxyamino- and 3’-Methoxyamino-2’,3’-Dideoxynucleosides

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    Aminonucleosides are used as key motifs in medicinal and bioconjugate chemistry; however, existing strategies toward 3′-hypernucleophilic amine systems do not readily deliver deoxyribo-configured products. We report diastereoselective syntheses of deoxyribo- and deoxyxylo-configured 3′-hydroxyamino- and 3′-methoxyamino-nucelosides from 3′-imine intermediates. The presence or absence of the 5′-hydroxyl-group protection dictates facial selectivity via inter- or intramolecular delivery of hydride from BH3 (borane). Protecting group screening gave one access to previously unknown 3′-methoxyamino-deoxyguanosine derivatives

    IRVE-II Post-Flight Trajectory Reconstruction

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    NASA s Inflatable Re-entry Vehicle Experiment (IRVE) II successfully demonstrated an inflatable aerodynamic decelerator after being launched aboard a sounding rocket from Wallops Flight Facility (WFF). Preliminary day of flight data compared well with pre-flight Monte Carlo analysis, and a more complete trajectory reconstruction performed with an Extended Kalman Filter (EKF) approach followed. The reconstructed trajectory and comparisons to an attitude solution provided by NASA Sounding Rocket Operations Contract (NSROC) personnel at WFF are presented. Additional comparisons are made between the reconstructed trajectory and pre and post-flight Monte Carlo trajectory predictions. Alternative observations of the trajectory are summarized which leverage flight accelerometer measurements, the pre-flight aerodynamic database, and on-board flight video. Finally, analysis of the payload separation and aeroshell deployment events are presented. The flight trajectory is reconstructed to fidelity sufficient to assess overall project objectives related to flight dynamics and overall, IRVE-II flight dynamics are in line with expectation

    History-deterministic Vector Addition Systems

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    We consider history-determinism, a restricted form of non-determinism, for Vector Addition Systems with States (VASS) when used as acceptors to recognise languages of finite words. History-determinism requires that the non-deterministic choices can be resolved on-the-fly; based on the past and without jeopardising acceptance of any possible continuation of the input word. Our results show that the history-deterministic (HD) VASS sit strictly between deterministic and non-deterministic VASS regardless of the number of counters. We compare the relative expressiveness of HD systems, and closure-properties of the induced language classes, with coverability and reachability semantics, and with and without ε\varepsilon-labelled transitions. Whereas in dimension 1, inclusion and regularity remain decidable, from dimension two onwards, HD-VASS with suitable resolver strategies, are essentially able to simulate 2-counter Minsky machines, leading to several undecidability results: It is undecidable whether a VASS is history-deterministic, or if a language equivalent history-deterministic VASS exists. Checking language inclusion between history-deterministic 2-VASS is also undecidable.Comment: This is the full version of a paper published in CONCUR 202

    A Study on Communication Behaviour of Extension Personnel of Prakasam District of Andhra Pradesh

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    Successful communication is the main job of an extension worker. He cannot expect change among farmers unless he is able to communicate effectively to them. This entails the extension personal to have thorough understanding of communication process. This study will be helpful in identifying important variables of extension personnel affecting their communication process. Prakasam District of Andhra Pradesh was selected by purposive random sampling. The study was conducted in 7 mandal's which were selected randomly. Respondents were Agricultural officers, agricultural extension officers, village agricultural assistants and village horticultural assistants. The total sample size for  the study were 120 extension personnel. majority of the respondents were female,  young aged, having high educational status, with low annual income, job experience and training exposure. Perceived work load was high, medium level of job satisfaction and low level of Innovativeness and medium level of achievement motivation and medium level of communication behaviour was observed. The findings of overall communication behaviour of extension personnel indicate that there is need to increase the communication behaviour from medium to high through suitable training programs on latest Communication technologies and communication skills, providing needed literature. View Article DOI: 10.47856/ijaast.2021.v08i11.00

    Combined Effects of Aircraft, Rail, and Road Traffic Noise on Total Noise Annoyance—A Cross-Sectional Study in Innsbruck

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    Noise legislation in Austria does not provide an assessment of the cumulative effect of noise from different sources. The desire of citizens for a total noise assessment is getting stronger. Within the pilot project &ldquo Gesamtl&auml rmbetrachtung&rdquo (Total Noise Investigation) Innsbruck, data from 1031 face-to-face interviews were correlated with exposure data from road, rail and air traffic noise. The interviews were selected in clusters according to the exposure combinations of these three sources. In addition to exposure-response relationships, it has also been found that the annoyance response to air and rail traffic noise is independent of the background noise from road traffic. The total noise annoyance response shows a cumulative effect in each source considered. From the source specific exposure-response relationships, a total noise assessment model based on the annoyance equivalents model was developed. This model is more suitable than the dominant source model and thus also considerable for legal application. Document type: Articl

    Investigation of Wetting Hydrodynamics Using Numerical Simulations

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    Meniscus shapes from a simulation of a plate immersing into an infinitely deep liquid bath, for a range of outer length scales, have been obtained numerically. These have been compared with the leading‐order prediction from a three‐region asymptotic analysis done in the double limit, Capillary number, Ca→0, LS/LC→0, with Ca ln(LC/LS) of O(1), where LS and LC represent the slip length and an outer macroscopic length, respectively. For Ca\u3c0.01, the numerically computed and the perturbation solutions show excellent agreement. Within this range of Ca, the meniscus slope at a distance 10LS from the dynamic contact line is geometry independent, that is, does not vary with changes in the outer length LC. The interface slope at this point can serve as an appropriate material boundary condition for the outer problem. For 0.0
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