1,318 research outputs found
To Adapt or Not to Adapt? Accommodating Change in Humanitarian Response (abstract)
What conditions facilitate or frustrate opportunities for adaptation during on-the-ground responses by non-governmental organizations (NGOs)? I seek to explain variation in the outcomes of adaptations by Doctors Without Borders (MSF)* during three crises: Ebola in West Africa in 2014, middle-income diseases after the Syrian Crisis, and HIV/AIDs and mental health in the late 1990s and early 2000s. This research shows that humanitarian organizations can be uniquely accommodating of uncertainty and change. In these cases political entrepreneurship by those in the field is filtered through an internal structure that deliberately accommodates debate and creative recombination of resources. Actors do not simply exploit ambiguous power relationships, networks, or informational resources for recombination (Sheingate, 2003). Rather, a decentralized organizational structure offers resources and deliberately facilitates the creation of novel ideas and solutions.
Interestingly, humanitarian action is facilitated by organizational structures that differ significantly from the centralized structures that best support human rights advocacy (Wong 2012). However, accommodation can be disrupted by the institutional constraints of the humanitarian mandate. Adaptation near this boundary sparks significant
*I use the French abbreviation for the organization because this is common to the movement. MSF stands for Médecins Sans Frontières
Absolute abundance estimates from shallow water baited underwater camera surveys; a stochastic modelling approach tested against field data
This research was supported by a University of Glasgow Faculty Scholarship to KMD, a Collaborative Gearing Scheme grant from the Natural Environmental Research Council and the British Antarctic Survey (CGS-77) and an ASSEMBLE infrastructure access grant to DMB.Baited underwater cameras are becoming a popular tool to monitor fish and invertebrate populations within protected and inshore environments where trawl surveys are unsuitable. Modelling the arrival times of deep-sea grenadiers using an inverse square relationship has enabled abundance estimates, comparable to those from bottom trawl surveys, to be gathered from deep-sea baited camera surveys. Baited underwater camera systems in the shallow water environments are however, currently limited to relative comparisons of assemblages based on simple metrics such as MaxN (maximum number of fish seen at any one time). This study describes a stochastic simulation approach used to model the behaviour of fish and invertebrates around a BUC system to enable absolute abundance estimates to be generated from arrival patterns. Species-specific models were developed for the tropical reef fishes the black tip grouper (Epinephelus fasciatus) and moray eel (Gymnothorax spp.) and the Antarctic scavengers; the asteroid (Odontaster validus) and the nemertean worm (Parbolasia corrugatus). A sensitivity analysis explored the impact of input parameters on the arrival patterns (MaxN, time to the arrival of the first individual and the time to reach MaxN) for each species generated by the model. Sensitivity analysis showed a particularly strong link between MaxN and abundance indicating that this model could be used to generate absolute abundances from existing or future MaxN data. It in effect allows the slope of the MaxN vs. abundance relationship to be estimated. Arrival patterns generated by each model were used to estimate population abundance for the focal species and these estimates were compared to data from underwater visual census transects. Using a Bland-Altman analysis, baited underwater camera data processed using this model were shown to generate absolute abundance estimates that were comparable to underwater visual census data.PostprintPeer reviewe
Exercise with Blood Flow Restriction: An Updated Evidence-Based Approach for Enhanced Muscular Development
A growing body of evidence supports the use of moderate blood flow restriction (BFR) combined with low-load resistance exercise to enhance hypertrophic and strength responses in skeletal muscle. Research also suggests that BFR during low-workload aerobic exercise can result in small but significant morphological and strength gains, and BFR alone may attenuate atrophy during periods of unloading. While BFR appears to be beneficial for both clinical and athletic cohorts, there is currently no common consensus amongst scientists and practitioners regarding the best practice for implementing BFR methods. If BFR is not employed appropriately, there is a risk of injury to the participant. It is also important to understand how variations in the cuff application can affect the physiological responses and subsequent adaptation to BFR training. The optimal way to manipulate acute exercise variables, such as exercise type, load, volume, inter-set rest periods and training frequency, must also be considered prior to designing a BFR training programme. The purpose of this review is to provide an evidence-based approach to implementing BFR exercise. These guidelines could be useful for practitioners using BFR training in either clinical or athletic settings, or for researchers in the design of future studies investigating BFR exercise
A COMPARISON OF IN VIVO CELLULAR RESPONSES TO CS-137 GAMMA RAYS AND 320-KV X RAYS
Research reported here relates to comparing the relative effectiveness of 320-kV X rays compared to Cs-137 gamma rays for two in vivo endpoints in C.B-17 mice after whole-body exposure: (1) cytotoxicity to bone marrow cells and splenocytes evaluated at 24-hours post exposure and (2) bone marrow and spleen reconstitution deficits (repopulation short- falls) evaluated at 6 weeks post exposure. We show that cytotoxicity dose-response rela- tionships for bone marrow cells and splenocytes are complex, involving negative curvature (decreasing slope as dose increases), presumably implicating a mixed cell population com- prised of large numbers of hypersensitive, modestly radiosensitive, and resistant cells. The radiosensitive cells appear to respond with 50% being killed by a dose \u3c 0.5 Gy. The X-ray relative biological effectiveness (RBE), relative to gamma rays, for destroying bone mar- row cells in vivo is \u3e 1, while for destroying splenocytes it is \u3c 1. In contrast, dose-response relationships for reconstitution deficits in the bone marrow and spleen of C.B-17 mice at 6 weeks after radiation exposure were of the threshold type with gamma rays being more effective in causing reconstitution deficit
Experimental Control and Characterization of Autophagy in Drosophila
Insects such as the fruit fly Drosophila melanogaster, which fundamentally reorganize their body plan during metamorphosis, make extensive use of autophagy for their normal development and physiology. In the fruit fly, the hepatic/adipose organ known as the fat body accumulates nutrient stores during the larval feeding stage. Upon entering metamorphosis, as well as in response to starvation, these nutrients are mobilized through a massive induction of autophagy, providing support to other tissues and organs during periods of nutrient deprivation. High levels of autophagy are also observed in larval tissues destined for elimination, such as the salivary glands and larval gut. Drosophila is emerging as an important system for studying the functions and regulation of autophagy in an in vivo setting. In this chapter we describe reagents and methods for monitoring autophagy in Drosophila, focusing on the larval fat body. We also describe methods for experimentally activating and inhibiting autophagy in this system and discuss the potential for genetic analysis in Drosophila to identify novel genes involved in autophagy
SMALL γ-RAY DOSES PREVENT RATHER THAN INCREASE LUNG TUMORS IN MICE
We show evidence for low doses of γ rays preventing spontaneous hyperplastic foci and adenomas in the lungs of mice, presumably via activating natural anticancer defenses. The evidence partly relates to a new study we conducted whereby a small number of female A/J mice received 6 biweekly dose fractions (100 mGy per fraction) of γ rays to the total body which prevented the occurrence of spontaneous hyperplastic foci in the lung. We also analyzed data from a much earlier Oak Ridge National Laboratory study involving more than 10,000 female RFMf/Un mice whereby single γ-ray doses from 100 to 1,000 mGy prevented spontaneous lung adenomas. We point out the possibility that the decrease in lung cancer mortality observed in The National Lung Screening Trial Research Team study involving lung tumor screening using low-dose computed tomography (CT) may relate at least in part to low-dose X-rays activating the body’s natural anticancer defenses (i.e., radiation hormesis). This possibility was apparently not recognized by the indicated research team
Preparation and ferroelectric properties of (124)-oriented SrBi4Ti4O15 ferroelectric thin film on (110)-oriented LaNiO3 electrode
A (124)-oriented SrBi4Ti4O15 (SBTi) ferroelectric thin film with high volume
fraction of {\alpha}SBTi(124)=97% was obtained using a metal organic
decomposition process on SiO2/Si substrate coated by (110)-oriented LaNiO3
(LNO) thin film. The remanent polarization and coercive field for
(124)-oriented SBTi film are 12.1 {\mu}C/cm2 and 74 kV/cm, respectively. No
evident fatigue of (124)-oriented SBTi thin film can be observed after
1{\times}10e9 switching cycles. Besides, the (124)-oriented SBTi film can be
uniformly polarized over large areas using a piezoelectric-mode atomic force
microscope. Considering that the annealing temperature was 650{\deg}C and the
thickness of each deposited layer was merely 30 nm, a long-range epitaxial
relationship between SBTi(124) and LNO(110) facets was proposed. The epitaxial
relationship was demonstrated based on the crystal structures of SBTi and LNO.Comment: 11 pages, 4 figures, published in Journal of Materials Science:
Materials in Electronics (JMSE), 19 (2008), 1031-103
Induced CMB quadrupole from pointing offsets
Recent claims in the literature have suggested that the {\it WMAP} quadrupole
is not primordial in origin, and arises from an aliasing of the much larger
dipole field because of incorrect satellite pointing. We attempt to reproduce
this result and delineate the key physics leading to the effect. We find that,
even if real, the induced quadrupole would be smaller than claimed. We discuss
reasons why the {\it WMAP} data are unlikely to suffer from this particular
systematic effect, including the implications for observations of point
sources. Given this evidence against the reality of the effect, the similarity
between the pointing-offset-induced signal and the actual quadrupole then
appears to be quite puzzling. However, we find that the effect arises from a
convolution between the gradient of the dipole field and anisotropic coverage
of the scan direction at each pixel. There is something of a directional
conspiracy here -- the dipole signal lies close to the Ecliptic Plane, and its
direction, together with the {\it WMAP} scan strategy, results in a strong
coupling to the component in Ecliptic co-ordinates. The dominant
strength of this component in the measured quadrupole suggests that one should
exercise increased caution in interpreting its estimated amplitude. The {\it
Planck} satellite has a different scan strategy which does not so directly
couple the dipole and quadrupole in this way and will soon provide an
independent measurement.Comment: 8 pages, 4 figure
Multiple time scales and the empirical models for stochastic volatility
The most common stochastic volatility models such as the Ornstein-Uhlenbeck
(OU), the Heston, the exponential OU (ExpOU) and Hull-White models define
volatility as a Markovian process. In this work we check of the applicability
of the Markovian approximation at separate times scales and will try to answer
the question which of the stochastic volatility models indicated above is the
most realistic. To this end we consider the volatility at both short (a few
days) and long (a few months)time scales as a Markovian process and estimate
for it the coefficients of the Kramers-Moyal expansion using the data for
Dow-Jones Index. It has been found that the empirical data allow to take only
the first two coefficients of expansion to be non zero that define form of the
volatility stochastic differential equation of Ito. It proved to be that for
the long time scale the empirical data support the ExpOU model. At the short
time scale the empirical model coincides with ExpOU model for the small
volatility quantities only.Comment: 19 pages, 6 figure
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