Non-blocking Priority Queue based on Skiplists with Relaxed Semantics

Priority queues are data structures that store information in an orderly fashion. They are of tremendous importance because they are an integral part of many applications, like Dijkstra’s shortest path algorithm, MST algorithms, priority schedulers, and so on. Since priority queues by nature have high contention on the delete_min operation, the design of an efficient priority queue should involve an intelligent choice of the data structure as well as relaxation bounds on the data structure. Lock-free data structures provide higher scalability as well as progress guarantee than a lock-based data structure. That is another factor to be considered in the priority queue design. We present a relaxed non-blocking priority queue based on skiplists. We address all the design issues mentioned above in our priority queue. Use of skiplists allows multiple threads to concurrently access different parts of the skiplist quickly, whereas relaxing the priority queue delete_min operation distributes contention over the skiplist instead of just at the front. Furthermore, a non-blocking implementation guarantees that the system will make progress even when some process fails. Our priority queue is internally composed of several priority queues, one for each thread and one shared priority queue common to all threads. Each thread selects the best value from its local priority queue and the shared priority queue and returns the value. In case a thread is unable to delete an item, it tries to spy items from other threads\u27 local priority queues. We experimentally and theoretically show the correctness of our data structure. We also compare the performance of our data structure with other variations like priority queues based on coarse-grained skiplists for both relaxed and non-relaxed semantics

Factors Affecting the Adoption of Genetically Modified Crops by Young and Beginning U.S. Farmers and Ranchers

The comprehensive set of programs in the 2008 Farm Bill designed to support Young and Beginning Farmers and Ranchers (YBFR), combined with a substantial amount of resources allocated to each of these programs, can be viewed as an investment in ensuring the future sustainability of the U.S. agriculture system. Understanding the factors that influence YBFR to adopt technology will become increasingly important if YBFR are to succeed. Of particular interest is why YBFR adopt Bt corn, Bt cotton, and HT soybeans. Results conform to a majority of our a priori expectations; YBFRs are more likely to adopt GM crops if they are not a full owner of the farm operation, as sales of the farm operation grow, if the crop is important to their region, and as they become more risk averse.Agricultural and Food Policy,

Engineering Geological and Geotechnical Studies of Taprang Landslide, West-central Nepal: An Approach for Slope Stability Analysis

Detailed investigation of Taprang landslide was carried out in order tounderstand the surface, subsurface lithological information and physicalproperties of soil by using multi-disciplinary methods such as engineeringgeological, geophysical and geotechnical studies for the determinationof factor of safety for slope stability analysis. Geological study wascarried out by detail mapping of surface geology, soil condition, propertiesof bedrock and its discontinuities. The geophysical survey (ElectricalResistivity Tomography-ERT) were carried out to know the electricalresistivity of soil for identifying the groundwater table and slip surface ofthe landslide. Geotechnical analysis such as grain size analysis, liquid limitand direct shear test were carried out in order to evaluate soil classification,moisture content, cohesion and the angle of internal friction of soil forknowing the strength the soil. These soil parameters indicate the soil is verylow strength. The combination of these results were used for calculatingthe factor of safety (FoS) by Limit Equilibrium Method (LEM) proposedby Bishop and Janbu methods. The result of factor of safety in the Tapranglandslide demonstrates that the slope become stable in drained (dry)condition, remain ultimate stage in undrained (wet) condition and finallyfailure occurs if applied the seismic load in both drained and undrainedconditions

Habitat suitability modeling of Asian Elephant Elephas maximus (Mammalia: Proboscidea: Elephantidae) in Parsa National Park, Nepal and its buffer zone

Asian Elephants Elephas maximus in Nepal are known to have habitats and movement corridors in Parsa National Park (PNP) and its buffer zone (BZ), located east of Chitwan National Park. A study was conducted in this area to assess the suitability of PNP and BZ as elephant use areas, and to determine factors relevant to the presence of elephants in PNP. Field measurements were carried out in 67 plots for vegetation analysis. Boosted Regression Tree (BRT) analysis was used to examine the relationship of habitat suitability and variables including topography (slope, aspect, altitude), climate (precipitation, temperature), habitat preference, ground cover and crown cover. The results indicate that elephant habitat suitability is mainly determined by the dominant plant species, temperature, altitude, habitat preference and precipitation. Slope, ground cover, crown cover and substrate have lesser effects. Elephants were recorded up to 400m in the northeast and southeast aspects of the study area. Most suitable habitats were low slope forest dominated by Acacia catechu and Myrsine semicerate that received 300mm annual precipitation. The model emphasizes environmental suitability, and contributes to knowledge for conservation of elephants in PNP and BZ by delineating sites that require specific planning and management.Peer reviewe

Child Trafficking and Associated Factors in Earthquake Affected Area of Nepal

Background: Recruitment, transportation, transfers, harboring, and/or receipt kidnapping of under 18 yrs child for the purpose of slavery, forced labor and exploitation is Child Trafficking. To assess the knowledge about child trafficking and factors associated with child trafficking in Gorkha district of Nepal Methods: Cross sectional study conducted to determine the knowledge and factors related to child trafficking in Gorkha district. Two urban municipalities selected purposively and other three rural municipalities were randomly selected.  Out of 160,772 households, total 300 households for survey was calculated by using Yamane formula (n) = N/ (1+Ne2). Wards of the municipalities were Primary Sampling Unit. Based on Population Proportionate Sampling technique; required number of households of each Wards was identified.  In Wards, households for survey were selected by using simple random method.  Head of the selected household were the respondent for household survey. Ten Key Informant Interviews were done with policemen, teachers, social workers, community leaders, stakeholders and six Focus Group Discussions were done with Youths (15-25 yrs), Parents and Social worker/teacher/community leader groups. Results: Remarkable proportions of respondents have correct knowledge about the child trafficking. Near relatives, unknown person, pears group, parents/family members and neighbor were common traffickers. During and after disaster is the most vulnerable time/event for child trafficking. False marriage, assuring lucrative job, asking for adoption and proposing good education were tricks of traffickers for child trafficking.  Homeless children, children travelling without parents, socially isolated children, children travelling at night, unprotected girl child like orphan, separated from family or without parent are most vulnerable for child Trafficking. Conclusions: Family, social groups, government officials and stakeholders should jointly initiate for anti child trafficking movement. School teacher and management committee should also take initiation to make fully aware to school going children about different dimension/aspect of Child Right and Child Trafficking

Setting research priorities to improve global newborn health and prevent stillbirths by 2025

Acknowledgements: The authors thank the expert group for their time and effort in this priority–setting exercise, and the contribution of anonymous reviewers to the final version of this report. We acknowledge inputs from Dr Diane Morof from Centers for Disease Control and Prevention, USA. Funding: This work was supported by Save the Children.Peer reviewedPublisher PD

Setting research priorities to improve global newborn health and prevent stillbirths by 2025.

BACKGROUND: In 2013, an estimated 2.8 million newborns died and 2.7 million were stillborn. A much greater number suffer from long term impairment associated with preterm birth, intrauterine growth restriction, congenital anomalies, and perinatal or infectious causes. With the approaching deadline for the achievement of the Millennium Development Goals (MDGs) in 2015, there was a need to set the new research priorities on newborns and stillbirth with a focus not only on survival but also on health, growth and development. We therefore carried out a systematic exercise to set newborn health research priorities for 2013-2025. METHODS: We used adapted Child Health and Nutrition Research Initiative (CHNRI) methods for this prioritization exercise. We identified and approached the 200 most productive researchers and 400 program experts, and 132 of them submitted research questions online. These were collated into a set of 205 research questions, sent for scoring to the 600 identified experts, and were assessed and scored by 91 experts. RESULTS: Nine out of top ten identified priorities were in the domain of research on improving delivery of known interventions, with simplified neonatal resuscitation program and clinical algorithms and improved skills of community health workers leading the list. The top 10 priorities in the domain of development were led by ideas on improved Kangaroo Mother Care at community level, how to improve the accuracy of diagnosis by community health workers, and perinatal audits. The 10 leading priorities for discovery research focused on stable surfactant with novel modes of administration for preterm babies, ability to diagnose fetal distress and novel tocolytic agents to delay or stop preterm labour. CONCLUSION: These findings will assist both donors and researchers in supporting and conducting research to close the knowledge gaps for reducing neonatal mortality, morbidity and long term impairment. WHO, SNL and other partners will work to generate interest among key national stakeholders, governments, NGOs, and research institutes in these priorities, while encouraging research funders to support them. We will track research funding, relevant requests for proposals and trial registers to monitor if the priorities identified by this exercise are being addressed