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Multiple sclerosis (MS) is a debilitating neurological disease associated with a variety of psychological, cognitive, and motoric symptoms. Walking is among the most important functions compromised by MS. Dual-task walking (DTW), an everyday activity in which people walk and engage in a concurrent, discrete task, has been assessed in MS, but little is known about how it relates to other MS symptoms. Self-awareness theory suggests that DTW may be a function of the interactions among psychological, cognitive, and motor processes.
Cognitive testing, self-report assessments for depression and falls self-efficacy (FSE), and walk evaluations [DTW and single-task walk (STW)] were assessed in seventy-three people with MS in a clinical care setting. Specifically, we assessed whether psychological factors (depression and FSE) that alter subjective evaluations regarding one’s abilities would moderate the relationships between physical and cognitive abilities and DTW performance.
DTW speed is related to diverse physical and cognitive predictors. In support of self-awareness theory, FSE moderated the relationship between STW and DTW speeds such that lower FSE attenuated the strength of the relationship between them. DTW costs – the change in speed normalized by STW speed – did not relate to cognitive and motor predictors. DTW costs did relate to depressive symptoms, and depressive symptoms moderated the effect of information processing on DTW costs.
Findings indicate that an interplay of physical ability and psychological factors – like depression and FSE – may enhance understanding of walking performance under complex, real-world, DTW contexts.
Double-crop grain sorghum after winter wheat harvest is a common cropping system in the southern plains region. Palmer amaranth is a troublesome weed in double-crop grain sorghum in Kansas. Populations resistant to various herbicides (e.g., atrazine, glyphosate, metsulfuron, pyrasulfotole) have made Palmer amaranth management even more difficult for producers. To evaluate control of atrazine-resistant and atrazine-susceptible Palmer amaranth in double-crop grain sorghum, we assessed 14 herbicide programs, of which 8 were PRE only and 6 were PRE followed by (fb) POST applications. Visible ratings of Palmer amaranth control were taken at 3 and 8 wk after planting (WAP) grain sorghum. PRE treatments containing very-long-chain fatty acid (VLCFA)–inhibiting herbicides provided 91% control of atrazine-resistant Palmer amaranth 3 WAP, and reduced weed density 8 WAP compared to atrazine-only PRE treatments. PRE fb POST treatments, especially those that included VLCFA-inhibiting herbicides, provided greater control (71% to 93%) of both atrazine-resistant and atrazine-susceptible Palmer amaranth, respectively, at 8 WAP compared to PRE treatments alone (59% to 79%). These results demonstrated the utility of VLCFA-inhibiting herbicides applied PRE and in a layered PRE fb POST approach in controlling atrazine-resistant Palmer amaranth, as well as the importance of an effective POST application following residual PRE herbicides for controlling both atrazine-resistant and atrazine-susceptible Palmer amaranth in double-crop grain sorghum.
Few studies have investigated the patterns of posttraumatic stress disorder (PTSD) symptom change in prolonged exposure (PE) therapy. In this study, we aimed to understand the patterns of PTSD symptom change in both PE and present-centered therapy (PCT).
Participants were active duty military personnel (N = 326, 89.3% male, 61.2% white, 32.5 years old) randomized to spaced-PE (S-PE; 10 sessions over 8 weeks), PCT (10 sessions over 8 weeks), or massed-PE (M-PE; 10 sessions over 2 weeks). Using latent profile analysis, we determined the optimal number of PTSD symptom change classes over time and analyzed whether baseline and follow-up variables were associated with class membership.
Five classes, namely rapid responder (7–17%), steep linear responder (14–22%), gradual responder (30–34%), non-responder (27–33%), and symptom exacerbation (7–13%) classes, characterized each treatment. No baseline clinical characteristics predicted class membership for S-PE and M-PE; in PCT, more negative baseline trauma cognitions predicted membership in the non-responder v. gradual responder class. Class membership was robustly associated with PTSD, trauma cognitions, and depression up to 6 months after treatment for both S-PE and M-PE but not for PCT.
Distinct profiles of treatment response emerged that were similar across interventions. By and large, no baseline variables predicted responder class. Responder status was a strong predictor of future symptom severity for PE, whereas response to PCT was not as strongly associated with future symptoms.
Synchrotron X-ray diffraction was used to monitor the hydrothermal precipitation of akaganeite (β-FeOOH) and its transformation to hematite (Fe2O3) in situ. Akaganeite was the first phase to form and hematite was the final phase in our experiments with temperatures between 150 and 200 °C. Akaganeite was the only phase that formed at 100 °C. Rietveld analyses revealed that the akaganeite unit-cell volume contracted until the onset of dissolution, and subsequently expanded. This reversal at the onset of dissolution was associated with a substantial and rapid increase in occupancy of the Cl site, perhaps by OH− or Fe3+. Rietveld analyses supported the incipient formation of an OH-rich, Fe-deficient hematite phase in experiments between 150 and 200 °C. The inferred H concentrations of the first crystals were consistent with “hydrohematite.” With continued crystal growth, the Fe occupancies increased. Contraction in both a- and c-axes signaled the loss of hydroxyl groups and formation of a nearly stoichiometric hematite.
A voluntary program is developed to achieve environmental goals through the self-interested choices of farmers under environmental risk and asymmetric information. Farmers behave to maximize expected net returns, and environmental quality standards are formulated through chance constraints. Because the government may not know each farmer's soil type, policy options must be self-selecting. The model is applied empirically to nitrate leaching and runoff from corn production in three New York regions. Asymmetric information between producers and the government would impose additional cost burdens on society, but these costs are modest in the context of other farm programs.
On October 29th, 2012, Hurricane Sandy caused a storm surge interrupting electricity with disruption to Manhattan’s (New York, USA) health care infrastructure. Beth Israel Medical Center (BIMC) was the only fully functioning major hospital in lower Manhattan during and after Hurricane Sandy. The impact on emergency department (ED) and hospital use by geriatric patients in lower Manhattan was studied.
The trends of ED visits and hospitalizations in the immediate post-Sandy phase (IPS) during the actual blackout (October 29 through November 4, 2012), and the extended post-Sandy phase (EPS), when neighboring hospitals were still incapacitated (November 5, 2012 through February 10, 2013), were analyzed with baseline. The analysis was broken down by age groups (18-64, 65-79, and 80+ years old) and included the reasons for ED visits and admissions.
During the IPS, there was a significant increase in geriatric visits (from 11% to 16.5% in the 65-79 age group, and from 6.5% to 13% in the 80+ age group) as well as in hospitalizations (from 22.7% to 25.2% in the 65-79 age group, and from 17.6% to 33.8% in the 80+ age group). However, these proportions returned to baseline during the EPS. The proportions of the categories “dialysis,” “respiratory device,” “social,” and “syncope” in geriatric patients in ED visits were significantly higher than younger patients. The increases of the categories “medication,” “dialysis,” “respiratory device,” and “social” represented two-thirds of absolute increase in both ED visits and admissions for the 65-79 age group, and half of the absolute increase in ED visits for the 80+ age group. The categories “social” and “respiratory device” peaked one day after the disaster, “dialysis” peaked two days after, and “medication” peaked three days after in ED visit analysis.
There was a disproportionate increase in ED visits and hospitalizations in the geriatric population compared with the younger population during the IPS. The primary factor of the disproportionate impact on the geriatric population appears to be from indirect effects of the hurricane, mainly due to the subsequent power outages, such as “dialysis,” “respiratory device,” and “social.” Further investigation by chart review may provide more insights to better aid with future disaster preparedness.
GotandaH, FogelJ, HuskG, LevineJM, PetersonM, BaumlinK, HabbousheJ. Hurricane Sandy: Impact on Emergency Department and Hospital Utilization by Older Adults in Lower Manhattan, New York (USA). Prehosp Disaster Med. 2015;30(5):496–502.
Because of the decline of the Ogallala Aquifer, water districts, regional water managers, and state water officers are becoming increasingly interested in conservation policies. This study evaluates both short-term and long-term water rights buyout policies. This research develops dynamic production functions for the major crops in the Texas Panhandle. The production functions are incorporated into optimal temporal allocation models that project annual producer behavior, crop choices, water use, and aquifer declines over 60 years. Results suggest that long-term buyouts may be more economically efficient than short-term buyouts.
This research analyzes two groundwater conservation policies in the Kansas High Plains located within the Ogallala aquifer: 1) cost-share assistance to increase irrigation efficiency; and 2) incentive payments to convert irrigated crop production to dryland crop production. To compare the cost-effectiveness of these two policies, a dynamic model simulated a representative irrigator's optimal technology choice, crop selection, and irrigation water use over time. The results suggest that the overall water-saving effectiveness can be improved when different policy tools are considered under different conditions. High prevailing crop prices greatly reduce irrigators' incentive to give up irrigation and therefore cause low enrollment and ineffectiveness of the incentive payment program. In areas with low aquifer-saturated thickness, the incentive payment program is more effective, whereas in areas with relatively higher water availability, the cost-share program could be a better choice.
This paper develops a framework for analysing intergovernmental relationships around greenhouse gas (GHG) mitigation policies along a cooperation-conflict spectrum that affects the probability of their enactment. Cooperative policies, such as federal fiscal transfers to sub-national governments, facilitate enactment. Coordination policies, including enabling and funding mechanisms, promote interdependence between jurisdictions. Competitive policies, such as federal performance standards and price mechanisms, increase political conflict over authority. We categorise 23 policies developed by over 1,500 state stakeholders into the cooperation/coordination/conflict taxonomy. If scaled to the national level, these policies could reduce GHG emissions by over 3 billion tonnes by 2020 and generate nearly 2.2 million jobs (1.19 per cent above baseline projections). Nearly two-thirds of the job gains are from coordinated and cooperative policy options that are unlikely to occur under the status quo policy process. We recommend a national climate action planning process to reduce GHG emissions while increasing aggregate economic efficiency.
We have developed a 350 μm radiometer to perform automated site testing in remote regions of Antarctica. In summer 2000–2001 the instrument operated at Concordia, a new station under construction at Dome C on the Antarctic Plateau. We present the results, and compare them with the atmospheric opacity measured at the South Pole in the same five-week period. During these five weeks, observing conditions at Dome C were, on average, substantially better than those at the South Pole.
We report an experimental study of photocarrier lifetime, transport, and excitation spectra in silicon-on-insulator doped with sulfur far above thermodynamic saturation. The spectral dependence of photocurrent in coplanar structures is consistent with photocarrier generation throughout the hyperdoped and undoped sub-layers, limited by collection of holes transported along the undoped layer. Holes photoexcited in the hyperdoped layer are able to diffuse to the undoped layer, implying (μτ)h ∼ 5 × 10−9 cm2/V. Although high absorptance of hyperdoped silicon is observed from 1200 to 2000 nm in transmission experiments, the number of collected electrons per absorbed photon is 10−4 of the above-bandgap response of the device, consistent with (μτ)e < 1 × 10−7cm2/V.
There are many reasons for seeking to create a global database with which to record the outcomes of therapy for congenital heart disease. Such a database can function as a tool to support a variety of purposes:
Though agriculture has long been recognized as a polluter, it has also more recently been noted as a provider of non-market benefits. Examples of these public goods that are by-products of agriculture include landscape amenities, a habitat for wildlife, and the preservation of agrarian cultural heritage (OECD 1997a; 1997b; Bohman et al., 1999). Though many of these benefits are difficult to define and measure, non-market valuation studies have found substantial non-market values for farmland in different regions around the world (Beasley, Workman, and Williams, 1986; Hackl and Pruckner, 1997; López, Shah and Altobello, 1994). The notion of agriculture providing a set of non-market goods and bads as joint products with market goods has given rise to the term “multifunctionality” (Lindland, 1998; Nersten and Prestegard, 1998; Runge, 1998). Conceptually, a “multifunctional” agriculture means that the agricultural production process is a multioutput technology, where some outputs are privately traded commodities and others are public goods. This case differs from standard environmental models where some activity in the economy generates a single externality.
The realization that agriculture is multifunctional has important implications for policy-making at both the domestic and international levels. In the domestic sphere, policies aimed at the various externalities from agriculture are typically legislated and administered independently. Likewise, the economics literature almost always examines externalities in isolation, either implicitly or explicitly assuming that other (potentially related) externalities are fixed or unimportant.