563 research outputs found
Collecting development data with mobile phones: Key considerations from a review of the evidence
Growth in mobile phone access and ownership
presents an opportunity to collect more data,
more frequently, from more people, and for less
money. There are multiple ways to collect data with
mobile phones (SMS, voice calls, etc.), each
with particular strengths and weaknesses.
n The best mode of data collection depends on the
characteristics of the target population (e.g.
literacy, network access, acceptability of using
mobile phones, etc.) and of the data to be
collected (e.g. quantitative vs. qualitative,
number of questions, sensitivity of information, etc)
Surveillance of Climate-smart Agriculture for Nutrition (SCAN): Innovations for monitoring climate, agriculture and nutrition at scale
Climate change will affect the ability to deliver not only the quantity but also the type and quality of food necessary for nutritious diets. Global and regional 'climate-smart agriculture' initiatives offer an opportunity to mitigate climate impacts and improve nutrition outcomes at scale. The Surveillance of Climate-smart Agriculture for Nutrition (SCAN) project develops new way to acquire, integrate and analyze data to determine what is climate-smart and nutrition-sensitive
Vertex Operators for Closed Superstrings
We construct an iterative procedure to compute the vertex operators of the
closed superstring in the covariant formalism given a solution of IIA/IIB
supergravity. The manifest supersymmetry allows us to construct vertex
operators for any generic background in presence of Ramond-Ramond (RR) fields.
We extend the procedure to all massive states of open and closed superstrings
and we identify two new nilpotent charges which are used to impose the gauge
fixing on the physical states. We solve iteratively the equations of the vertex
for linear x-dependent RR field strengths. This vertex plays a role in studying
non-constant C-deformations of superspace. Finally, we construct an action for
the free massless sector of closed strings, and we propose a form for the
kinetic term for closed string field theory in the pure spinor formalism.Comment: TeX, harvmac, amssym.tex, 41 pp; references adde
Note About Classical Dynamics of Pure Spinor String on AdS_5 x S_5 Background
We will discuss some properties of the pure spinor string on the AdS_5 x S_5
background. Using the classical Hamiltonian analysis we will show that the
vertex operator for the massless state that is in the cohomology of the BRST
charges describes on-shell fluctuations around AdS_5 x S_5 background.Comment: 26. pages, added references, v2:corrected typo
Light Composite Vector Bosons
In gauge theories with slowly-running coupling constants, it may be possible
for four-fermion operators to be nearly marginal. Such operators can possess
asymptotically weak couplings, and can plausibly give rise to light composite
vector mesons.Comment: 16 pages (TeX w/epsf), 4 figures (uuencoded) included,
CERN-TH.6767/9
Origin of Pure Spinor Superstring
The pure spinor formalism for the superstring, initiated by N. Berkovits, is
derived at the fully quantum level starting from a fundamental
reparametrization invariant and super-Poincare invariant worldsheet action. It
is a simple extension of the Green-Schwarz action with doubled spinor degrees
of freedom with a compensating local supersymmetry on top of the conventional
kappa-symmetry. Equivalence to the Green-Schwarz formalism is manifest from the
outset. The use of free fields in the pure spinor formalism is justified from
the first principle. The basic idea works also for the superparticle in 11
dimensions.Comment: 21 pages, no figure; v2: refs. adde
Pure spinor superfields -- an overview
Maximally supersymmetric theories do not allow off-shell superspace
formulations with traditional superfields containing a finite set of auxiliary
fields. It has become clear that off-shell supersymmetric action formulations
of such models can be achieved by the introduction of pure spinors. In this
talk, an overview of this formalism is given, with emphasis on D=10
super-Yang-Mills theory and D=11 supergravity. This a somewhat expanded version
of a talk presented at the workshop "Breaking of supersymmetry and ultraviolet
divergences in extended supergravity" (BUDS), Laboratori Nazionali di Frascati,
March 25-28, 2013.Comment: 34 pp., 2 figs., contributions to the proceedings of the workshop
"Breaking of supersymmetry and ultraviolet divergences in extended
supergravity" (BUDS), Laboratori Nazionali di Frascati, March 25-28, 201
Non-BPS D-Branes in Light-Cone Green-Schwarz Formalism
Non-BPS D-branes are difficult to describe covariantly in a manifestly
supersymmetric formalism. For definiteness we concentrate on type IIB string
theory in flat background in light-cone Green-Schwarz formalism. We study both
the boundary state and the boundary conformal field theory descriptions of
these D-branes with manifest SO(8) covariance and go through various
consistency checks. We analyze Sen's original construction of non-BPS D-branes
given in terms of an orbifold boundary conformal field theory. We also directly
study the relevant world-sheet theory by deriving the open string boundary
condition from the covariant boundary state. Both these methods give the same
open string spectrum which is consistent with the boundary state, as required
by the world-sheet duality. The boundary condition found in the second method
is given in terms of bi-local fields that are quadratic in Green-Schwarz
fermions. We design a special ``doubling trick'' suitable to handle such
boundary conditions and prescribe rules for computing all possible correlation
functions without boundary insertions. This prescription has been tested by
computing disk one-point functions of several classes of closed string states
and comparing the results with the boundary state computation.Comment: 47 pages, 1 figure. Typos corrected, references added and slight
modification of certain explanation made. Version accepted for publication in
JHE
The scientific basis of climate-smart agriculture: A systematic review protocol
Background: ‘Climate-smart agriculture’ (CSA)—agriculture and food systems that
sustainably increase food production, improve resilience (or adaptive capacity) of farming
systems, and mitigate climate change when possible—has quickly been integrated into the
global development agenda. However, the empirical evidence base for CSA has not been
assembled, complicating the transition from CSA concept to concrete actions, and
contributing to ideological disagreement among development practitioners. Thus, there is an
urgent need to evaluate current knowledge on the effectiveness of CSA to achieve its intended
benefits and inform discourse on food, agriculture, and climate change. This systematic
review intends to establish the scientific evidence base of CSA practices to inform the next
steps in development of agricultural programming and policy. We will evaluate the impact of
73 promising farm-level management practices across five categories (agronomy,
agroforestry, livestock, postharvest management, and energy systems) to assess their
contributions to the three CSA pillars: (1) agronomic and economic productivity, (2)
resilience and adaptive capacity, and (3) climate change mitigation in the developing world.
The resulting data will be compiled into a searchable Web-based database and analytical
engine that can be used to assess the relative effectiveness and strength of evidence for CSA,
as well as identify best-fit practices for specific farming and development contexts. This
represents the largest meta-analysis of agricultural practices to date.
Methods/Design: This protocol sets out the approach for investigating the question: How do
farm-level CSA management practices and technologies affect food production and/or
farmers’ incomes, resilience/adaptive capacity, and climate change mitigation in farming
systems of developing countries? The objective of this ongoing systematic review is to
provide a first appraisal of the evidence for CSA practices in order to inform subsequent
programming. The review is based on data found in English-language peer-reviewed journals
with searches using terms relevant to CSA practices and CSA outcomes. Searches were
conducted via Web of Science (WoS) and Scopus. Articles located were screened first by
abstract and then full text according to predefined eligibility criteria for inclusion in the
review. Data capturing the context of the study (e.g., geographic location, environmental
context), management practices, and impacts (e.g., indicators of CSA outcomes) will be
compiled from those studies that meet the predetermined criteria. Statistical relationships
between practices and impacts will be evaluated via meta-analytical approaches including
response ratios and effect sizes. Mechanisms to identify bias and maintain consistency
continue to be applied throughout the review process. These analyses will be complemented
with an analysis of determinants of/barriers to adoption of promising CSA practices covered
in the meta-analysis. Results of the review will be incorporated into a publicly available Web-based
database. Data will be publicly available under Creative Commons License in 2016
Ethics and social responsibility in practice: interpreters and translators engaging with and beyond the professions
Interpreting and translation are unregulated activities in most countries, yet interpreters and translators perform challenging work in sensitive domains, such as the law, medicine and social work. Other professionals working in these sectors must complete formal ethics training to qualify, then subscribe to Codes of Practice or Ethics. When they face ethical challenges in their work, they can access ongoing support. They must undertake regular refresher training in ethics. Interpreters and translators rarely have access to this sort of ethical infrastructure. This places the onus on interpreters and translators to reflect on ethical aspects of their practice, for reasons related to both professional performance and social responsibility. This contribution presents original UK-based research with one type of professional ‘clients’ who rely on interpreters and translators, social workers and social work students prior to their first work experience placement. Findings suggest that insufficient attention has been paid to such professional clients and that ethical aspects of professional communication can be compromised as a result. By framing ethics training and ongoing support in terms of social responsibility, we point to some ways in which the different professional groups might communicate and work more effectively with one another and with service users
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