427 research outputs found
Effects of Rate of Drying, Life History Phase, and Ecotype on the Ability of the Moss Bryum Argenteum to Survive Desiccation Events and the Influence on Conservation and Selection of Material for Restoration
Desiccation stress is frequently experienced by the moss Bryum argenteum and can influence survival, propagation and niche selection. We attempted to disentangle the interacting factors of life history phase (five categories) and rate of desiccation (time allotted for induction of desiccation tolerance) for 13 ecotypes of B. argenteum. Using chlorophyll fluorescence as a stress index, we determined how these parameters influenced desiccation tolerance. Rate of drying and life phase significantly affected desiccation tolerance. The reaction norms of desiccation tolerance displayed by the 13 ecotypes showed a substantial degree of variation in phenotypic plasticity. We observed differences in survival and fluorescence between rapid and slow drying events in juveniles. These same drying applications did not produce as large of a response for adult shoots (which consistently displayed high values). Some juvenile and protonemal ecotypes, such as those from the southwest United States, possessed higher innate tolerance to rapid drying, and greater resilience compared to ecotypes sourced from mesic localities in the United States. These results show a complex nuanced response to desiccation with ecotypes displaying a range of responses to desiccation reflecting both inherently different capacities for tolerating desiccation as well as variation in capacity for phenotypic plasticity. Our results suggest that we should expect few short-term effects of climate change due to high desiccation tolerance of adult shoots, but significant adverse long-term effects on colony establishment due to low tolerance of protonema and juvenile shoots. Further, we would recommend that future studies using mosses for habitat restoration of aridlands consider the desiccation tolerance capacity of individual ecotypes used for cultivation and later re-introduction. Understanding how mosses respond to desiccation is essential to interpret ecological roles, habitat preferences, selective pressures, and responses to climate change, and to estimate the potential effects of climate changes on bryophyte species and populations
Lubricant degradation, transport and the effect of extended oil drain intervals on piston assembly tribology
There are ever increasing demands on lubricant manufacturers to meet governmental legislation and customer needs by improving fuel economy, engine durability and exhaust system compatibility as shown by the introduction of GF4 and move towards GF5 specification oils. This has created an ever increasing need to understand how oil degrades in an engine and how this degraded oil affects piston assembly tribology. This review conference paper will give an overview of a collaborative project that has been undertaken to further enhance the understanding of how lubricant degrades in an operating engine, its transport through the engine and effect upon piston assembly tribology
Extraction and tribological investigation of top piston ring zone oil from a gasoline engine
With tightening emission regulations, increased expected fuel economy, and longer drain intervals impacting on lubricant formulation, greater understanding of how oil degrades in an automotive engine is becoming ever more important. Equally significant is the effect that this degraded lubricant has on the tribological operation of the engine, particularly its overall internal friction and component wear. In a previous paper, four tests to degrade oil in a single cylinder engine were reported [1]. These tests were set up such that the lubricating oil was degraded in the ring pack before returning to the sump, where it was sampled and chemical and rheological analysis undertaken. This paper reports the extension of this work using the same Hydra engine and describes how oil has additionally been extracted from the rear of the top piston ring during engine operation. This extracted oil has then been subjected to similar analysis as the sump oil samples in the previous tests, along with additional analysis to look at the tribological properties of the oil using tribometers. The results clearly show significant differences in the rheological, tribological, and chemical properties of the fresh oil and used sump oil samples when compared with the top ring zone (TRZ) oil samples, particularly the effect of load on the levels of volatiles present in the TRZ samples and their effect on traction and friction coefficient values during tribological testing
Combatir la dependencia y promover la protecciĂłn infantil en Ruanda
Depender constantemente de una ayuda que aumenta y disminuye a lo largo del tiempo y que procede en gran medida de fuentes externas puede producir la sensaciĂłn de no tener poder alguno, ademĂĄs de menoscabar las iniciativas basadas en las familias y en la comunidad para proteger a los menores
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Setting global research priorities for child protection in humanitarian action: Results from an adapted CHNRI exercise
Background
Armed conflict, natural disaster, and forced displacement affect millions of children each year. Such humanitarian crises increase the risk of family separation, erode existing support networks, and often result in economic loss, increasing childrenâs vulnerability to violence, exploitation, neglect, and abuse. Research is needed to understand these risks and vulnerabilities and guide donor investment towards the most effective interventions for improving the well-being of children in humanitarian contexts.
Methods
The Assessment, Measurement & Evidence (AME) Working Group of the Alliance for Child Protection in Humanitarian Action (ACPHA) identified experts to participate in a research priority setting exercise adapted from the Child Health and Nutrition Research Initiative (CHNRI). Experts individually identified key areas for research investment which were subsequently ranked by participants using a Likert scale. Research Priority Scores (RPS) and Average Expert Agreement (AEA) were calculated for each identified research topic, the top fifteen of which are presented within this paper.
Results
Intervention research, which aims to rigorously evaluate the effectiveness of standard child protection activities in humanitarian settings, ranked highly. Child labor was a key area of sector research with two of the top ten priorities examining the practice. Respondents also prioritized research efforts to understand how best to bridge humanitarian and development efforts for child protection as well as identifying most effective way to build the capacity of local systems in order to sustain child protection gains after a crisis.
Conclusions
Rigorous, scientific research that assesses the scope of child protection risks, examines the effectiveness of interventions to improve child well-being, and translates evidence to practice is critical. Findings from this research priority setting exercise offer guidance for a global research agenda on child protection in humanitarian settings, encouraging cooperation among donors, implementers, and academics to pursue a coordinated approach to evidence generation
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Local constructions of gender-based violence amongst IDPs in northern Uganda: analysis of archival data collected using a gender- and age-segmented participatory ranking methodology
Background
Gender-based violence (GBV) is a significant problem in conflict-affected settings. Understanding local constructions of such violence is crucial to developing preventive and responsive interventions to address this issue.
Methods
This study reports on a secondary analysis of archived data collected as part of formative qualitative work â using a group participatory ranking methodology (PRM) â informing research on the prevalence of GBV amongst IDPs in northern Uganda in 2006. Sixty-four PRM group discussions were held with women, with men, with girls (aged 14 to 18Â years), and with boys (aged 14 to 18Â years) selected on a randomized basis across four internally displaced persons (IDP) camps in Lira District. Discussions elicited problems facing women in the camps, and â through structured participatory methods - consensus ranking of their importance and narrative accounts explaining these judgments.
Results
Amongst forms of GBV faced by women, rape was ranked as the greatest concern amongst participants (with a mean problem rank of 3.4), followed by marital rape (mean problem rank of 4.5) and intimate partner violence (mean problem rank of 4.9). Girls ranked all forms of GBV as higher priority concerns than other participants. Discussions indicated that these forms of GBV were generally considered normalized within the camp. Gender roles and power, economic deprivation, and physical and social characteristics of the camp setting emerged as key explanatory factors in accounts of GBV prevalence, although these played out in different ways with respect to differing forms of violence.
Conclusions
All groups acknowledged GBV to represent a significant threat - among other major concerns such as transportation, water, shelter, food and security â for women residing in the camps. Given evidence of the significantly higher risk in the camp of intimate partner violence and marital rape, the relative prominence of the issue of rape in all rankings suggests normalization of violence within the home. Programs targeting reduction in GBV need to address community-identified root causes such as economic deprivation and social norms related to gender roles. More generally, PRM appears to offer an efficient means of identifying local constructions of prevailing challenges in a manner that can inform programming
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Adolescent demand for contraception and family planning services in low- and middle-income countries: A systematic review
An estimated 23 million adolescent girls age 15â19 in low- and middle-income countries (LMICs) have an unmet need for contraception. Despite the recognised importance of expanding access to appropriate methods of contraceptives for adolescents in LMICs, the evidence base on their total demand for contraception is limited, and there is no consensus on how to measure this important phenomenon. The aim of this study was to review the published literature in order to better understand the level of adolescent demand for contraception in LMICs and to explore what demand-related indicators are being measured. A total of 1375 articles were identified and 18 met the inclusion criteria. Included studies reported findings from 29 LMICs, revealing high adolescent demand for contraception. The demand for contraception among adolescents and young women ranged from 22% among married adolescents in Azerbaijan to 98% in Peru. However, measures of this phenomenon were limited, with most studies only reporting current contraceptive use or unmet need. Most studies relied on cross-sectional data, and young, unmarried, and male adolescents were largely excluded. We make several recommendations for alternative approaches for a more comprehensive understanding of adolescent demand for contraception in LMICs
Inductive power transfer for on-body sensors defining a design space for safe, wirelessly powered on-body health sensors
Pervasive Health: 9th International Conference on Pervasive Computing Technologies for Healthcare, 20-23 May 2015, Istanbul, TurkeyDesigners of on-body health sensing devices face a difficult choice. They must either minimise the power consumption of devices, which in reality means reducing the sensing capabilities, or build devices that require regular battery changes or recharging. Both options limit the effectiveness of devices. Here we investigate an alternative. This paper presents a method of designing safe, wireless, inductive power transfer into on-body sensor products. This approach can produce sensing devices that can be worn for longer durations without the need for human intervention, whilst also having greater sensing and data capture capabilities. The paper addresses significant challenges in achieving this aim, in particular: device safety, sufficient power transfer, and human factors regarding device geometry. We show how to develop a device that meets stringent international safety guidelines for electromagnetic energy on the body and describe a design space that allows designers to make trade-offs that balance power transfer with other constraints, e.g. size and bulk, that affect the wearability of devices. Finally we describe a rapid experimental method to investigate the optimal placement of on-body devices and the actual versus theoretical power transfer for on-body, inductively powered devices. EPSR
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Evaluating the reliability and validity of secondary reporting to measure gender-based violence in conflict and disaster
Alastair Ager - ORCID 0000-0002-9474-3563
https://orcid.org/0000-0002-9474-3563Replaced AM with VoR 2020-08-10Background
Accurately identifying the magnitude of gender-based violence (GBV) in humanitarian settings is hindered by logistical and methodological complexities. The âNeighborhood Methodâ, an adapted household survey that uses primary and secondary reporting to assess the prevalence of GBV in humanitarian settings, reduces the length of time and cost associated with traditional surveys. Primary female adult respondents disclose incidents of physical violence, intimate and non-intimate partner rape for themselves, other females in their homes (standard reporting) and other women and children in their social networks (secondary reporting). This study examines the reliability and validity of this inclusion of secondary reporting to determine the comparability of the Neighborhood Method to a traditional survey approach.Methods
Drawing on data from 1,180 women reporting on 3,744 females in respondent households and 15,086 in neighboring households across four humanitarian settings (Ethiopia/ Somalia, Liberia, Sri Lanka, and Uganda), reliability of secondary reporting was measured through intra-class correlation coefficients (ICCs) and Cohenâs kappas. Validity was assessed using two-sample z-tests for differences between standard versus secondary reporting.Results
Prevalence estimates comparing a respondentâs household with a neighboring household show closer agreement (ICC: 0.999-0.986) than self-reports vs. secondary reporting on a female counterpoint in a neighboring home (ICC: 0.939-0.98). Kappa statistics analyzing the reliability of two separate neighbors reporting on a third neighbor showed moderate agreement beyond chance alone (Îș = 0.45 for physical violence and 0.48 for rape). Prevalence rates corresponded between standard and secondary reports (i.e. showed no statistical difference) in 18 out of 24 compared populations.Conclusions
For prevalence of GBV, secondary reporting about neighbors can serve as a useful adjunct to standard survey methodology. Findings offer important initial insights into the consistency and accuracy of secondary reporting as a tool for field epidemiologists in humanitarian settings.https://doi.org/10.1186/s13031-020-00301-014pubpu
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