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Adaptation and development pathways for different types of farmers
One of the greatest challenges humanity faces is feeding the world's human population in a sustainable, nutritious, equitable and ethical way under a changing climate. Urgent transformations are needed that allow farmers to adapt and develop while also being climate resilient and contributing minimal emissions. This paper identifies several illustrative adaptation and development pathways, recognising the variety of starting points of different types of farmers and the ways their activities intersect with global trends, such as population growth, climate change, rapid urbanisation dietary changes, competing land uses and the emergence of new technologies. The feasibility of some pathways depends on factors such as farm size and land consolidation. For other pathways, particular infrastructure, technology, access to credit and market access or collective action are required. The most viable pathway for some farmers may be to exit agriculture altogether, which itself requires careful management and planning. While technology offers hope and opportunity, as a disruptor, it also risks maladaptations and can create tradeoffs and exacerbate inequalities, especially in the context of an uncertain future. For both the Sustainable Development Goals and the 2015 Paris Agreement to be achieved, a mix of levers that combine policy, technology, education and awareness-raising, dietary shifts and financial/economic mechanisms is required, attending to multiple time dimensions, to assist farmers along different pathways. Vulnerable groups such as women and the youth must not be left behind. Overall, strong good governance is needed at multiple levels, combining top-down and bottom-up processes
Predicting magnetopause crossings at geosynchronous orbit during the Halloween storms
[1] In late October and early November of 2003, the Sun unleashed a powerful series of events known as the Halloween storms. The coronal mass ejections launched by the Sun produced several severe compressions of the magnetosphere that moved the magnetopause inside of geosynchronous orbit. Such events are of interest to satellite operators, and the ability to predict magnetopause crossings along a given orbit is an important space weather capability. In this paper we compare geosynchronous observations of magnetopause crossings during the Halloween storms to crossings determined from the Lyon-Fedder-Mobarry global magnetohydrodynamic simulation of the magnetosphere as well to predictions of several empirical models of the magnetopause position. We calculate basic statistical information about the predictions as well as several standard skill scores. We find that the current Lyon-Fedder-Mobarry simulation of the storm provides a slightly better prediction of the magnetopause position than the empirical models we examined for the extreme conditions present in this study. While this is not surprising, given that conditions during the Halloween storms were well outside the parameter space of the empirical models, it does point out the need for physics-based models that can predict the effects of the most extreme events that are of significant interest to users of space weather forecasts
A profile of children with complex chronic conditions at end of life among Medicaid beneficiaries: Implications for health care reform
Background: As the United States braces for full implementation of health care reform, the eyes of the nation are on Medicaid. The large number of newly eligible Medicaid beneficiaries may challenge health care resources and ultimately impact quality of care. This is a special concern among current Medicaid beneficiaries such as children with complex chronic conditions (CCCs) who have significant health care needs, especially at end of life (EOL). Yet, a comprehensive profile of these children is lacking.
Objective: To understand the demographic and health characteristics, health care utilization, and expenditures among Medicaid children with CCCs at EOL.
Methods: Our study used a retrospective cohort design with data from the 2007 and 2008 California Medicaid data files. Descriptive statistics were used to profile children in the last year of life.
Results: We found a diverse group of children who suffered with serious, multiple chronic conditions, and who accessed comprehensive, multidisciplinary care. Most children had neuromuscular conditions (54%), cardiovascular conditions (46%), and cancer (30%). A majority (56%) had multiple CCCs. Children with CCCs received comprehensive care including hospital inpatient (67%), primary (82%), ancillary (87%), and other acute care services (83%); however, few children utilized hospice and home health care services (26%). Significant age differences existed among the children.
Conclusions: The current California Medicaid system appears to provide comprehensive care for children at EOL. The underutilization of hospice and home health services, however, represents an opportunity to improve the quality of EOL care while potentially reducing or remaining budget neutral
Low-frequency noise reduction of spacecraft structures
Low frequency noise reduction of spacecraft structure
Oxygen isotopes implanted in the LDEF spacecraft
Secondary ion mass spectrometry was used to study oxygen implanted in the surface of copper from the Long Duration Exposure Facility (LDEF). Oxidation that occurred in orbit shows a characteristic oxygen isotope composition, depleted in O-18. The measured depletion is comparable to the predicted depletion (45 percent) based on a model of the gravitational separation of the oxygen isotopes. The anomalous oxygen was contained within 10nm of the surface. Tray E10 was calculated to have received 5.14 x 10(exp 21) atoms of oxygen cm(sup -2) during the LDEF mission and so there is sufficient anomalous implanted oxygen present in the surface to obtain a reliable isotopic profile
Fatigue risk assessment of a Helicopter Emergency Medical Service crew working a 24/7 shift pattern:results of a prospective service evaluation
Background: The work of Helicopter Emergency Medical Services (HEMS) teams crosses the boundaries of several high-risk occupations including medicine, aviation, and transport. Working conditions can be challenging and operational demands requires a 24-h rota, resulting in disruption of the normal circadian rhythm. HEMS crews are therefore prone to both mental and physical fatigue. As fatigue in medical providers is linked to poor cognitive performance, degradation of psychomotor skills and error, this study aimed to explore the existence of predictable patterns of crew-fatigue in a HEMS service.Methods: HEMS medical crew members working a 3-on 3-off forward rotating rota with a 5-week shift cycle were asked to do psychomotor vigilance tests (PVT) as an objective measure of fatigue. PVT testing was undertaken at the start, mid- and at the end of every shift during a full 5-week shift cycle. In addition, they were asked to score subjective tiredness with the Samn-Perelli Fatigue Scale (SPFS), and to keep a Transport Fatigue Assessment shift log, wherein they noted shift characteristics potentially related to fatigue. Primary outcome of interest was defined as the change in PVT and SPFS scores over time.Results: Mean baseline resting PVT in milliseconds at the start of the study period was 427 [390–464]. There was an overall trend towards higher PVT-scores with shift progression mean [95% CI] PVT at the start of shifts 447 [433–460]; halfway through the shift 452 [440–463]; end of the shift 459 [444–475], p = 0.10), whereas SPFS scores remained constant. Within a 5 week forward-rotating cycle, an overall trend towards a gradual increase in both average PVT (from 436 [238–454] to 460 [371–527, p = 0.68] ms;) and SPFS (from 2.9 [2.6–3.2] to 3.6 [3.1–4.0], p = 0.38) was observed, although significant interindividual variation was present. Reported SPFS scores ≥ 4 (moderate fatigue) were mainly related to workload (number of jobs) and transport mode (car-based shifts).Conclusion: An overall trend towards a decline in psychomotor vigilance and an increase in self-reported tiredness was found for HEMS crew over a 5-week shift cycle. Using a bespoke predictive fatigue tool on a day-to-day basis could increase fatigue awareness and provide a framework to which relevant mitigating options can be applied.</p
Anomalous Spin Polarization of GaAs Two-Dimensional Hole Systems
We report measurements and calculations of the spin-subband depopulation,
induced by a parallel magnetic field, of dilute GaAs two-dimensional (2D) hole
systems. The results reveal that the shape of the confining potential
dramatically affects the values of in-plane magnetic field at which the upper
spin subband is depopulated. Most surprisingly, unlike 2D electron systems, the
carrier-carrier interaction in 2D hole systems does not significantly enhance
the spin susceptibility. We interpret our findings using a multipole expansion
of the spin density matrix, and suggest that the suppression of the enhancement
is related to the holes' band structure and effective spin j=3/2.Comment: 6 pages, 4 figures, substantially extended discussion of result
High fidelity quantum memory via dynamical decoupling: theory and experiment
Quantum information processing requires overcoming decoherence---the loss of
"quantumness" due to the inevitable interaction between the quantum system and
its environment. One approach towards a solution is quantum dynamical
decoupling---a method employing strong and frequent pulses applied to the
qubits. Here we report on the first experimental test of the concatenated
dynamical decoupling (CDD) scheme, which invokes recursively constructed pulse
sequences. Using nuclear magnetic resonance, we demonstrate a near order of
magnitude improvement in the decay time of stored quantum states. In
conjunction with recent results on high fidelity quantum gates using CDD, our
results suggest that quantum dynamical decoupling should be used as a first
layer of defense against decoherence in quantum information processing
implementations, and can be a stand-alone solution in the right parameter
regime.Comment: 6 pages, 3 figures. Published version. This paper was initially
entitled "Quantum gates via concatenated dynamical decoupling: theory and
experiment", by Jacob R. West, Daniel A. Lidar, Bryan H. Fong, Mark F. Gyure,
Xinhua Peng, and Dieter Suter. That original version split into two papers:
http://arxiv.org/abs/1012.3433 (theory only) and the current pape
Electrical activation and electron spin resonance measurements of implanted bismuth in isotopically enriched silicon-28
We have performed continuous wave and pulsed electron spin resonance
measurements of implanted bismuth donors in isotopically enriched silicon-28.
Donors are electrically activated via thermal annealing with minimal diffusion.
Damage from bismuth ion implantation is repaired during thermal annealing as
evidenced by narrow spin resonance linewidths (B_pp=12uT and long spin
coherence times T_2=0.7ms, at temperature T=8K). The results qualify ion
implanted bismuth as a promising candidate for spin qubit integration in
silicon.Comment: 4 pages, 4 figure
Electron spin relaxation of N@C60 in CS2
We examine the temperature dependence of the relaxation times of the
molecules N@C60 and N@C70 (which comprise atomic nitrogen trapped within a
carbon cage) in liquid CS2 solution. The results are inconsistent with the
fluctuating zero field splitting (ZFS) mechanism, which is commonly invoked to
explain electron spin relaxation for S > 1/2 spins in liquid solution, and is
the mechanism postulated in the literature for these systems. Instead, we find
a clear Arrhenius temperature dependence for N@C60, indicating the spin
relaxation is driven primarily by an Orbach process. For the asymmetric N@C70
molecule, which has a permanent non-zero ZFS, we resolve an additional
relaxation mechanism caused by the rapid reorientation of its ZFS. We also
report the longest coherence time (T2) ever observed for a molecular electron
spin, being 0.25 ms at 170K.Comment: 6 pages, 6 figures V2: Updated to published versio
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