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In this paper we study the Assouad dimension of graphs of certain Lévy processes and functions defined by stochastic integrals. We do this by introducing a convenient condition which guarantees a graph to have full Assouad dimension and then show that graphs of our studied processes satisfy this condition.
Patients with cardiovascular diseases are common in the emergency department (ED), and continuity of care following that visit is needed to ensure that they receive evidence-based diagnostic tests and therapy. We examined the frequency of follow-up care after discharge from an ED with a new diagnosis of one of three cardiovascular diseases.
We performed a retrospective cohort study of patients with a new diagnosis of heart failure, atrial fibrillation, or hypertension, who were discharged from 157 non-pediatric EDs in Ontario, Canada, between April 2007 and March 2014. We determined the frequency of follow-up care with a family physician, cardiologist, or internist within seven and 30 days, and assessed the association of patient, emergency physician, and family physician characteristics with obtaining follow-up care using cause-specific hazard modeling.
There were 41,485 qualifying ED visits. Just under half (47.0%) had follow-up care within seven days, with 78.7% seen by 30 days. Patients with serious comorbidities (renal failure, dementia, COPD, stroke, coronary artery disease, and cancer) had a lower adjusted hazard of obtaining 7-day follow-up care (HRs 0.77-0.95) and 30-day follow-up care (HR 0.76-0.95). The only emergency physician characteristic associated with follow-up care was 5-year emergency medicine specialty training (HR 1.11). Compared to those whose family physician was remunerated via a primarily fee-for-service model, patients were less likely to obtain 7-day follow-up care if their family physician was remunerated via three types of capitation models (HR 0.72, 0.81, 0.85) or via traditional fee-for-service (HR 0.91). Findings were similar for 30-day follow-up care.
Only half of patients discharged from an ED with a new diagnosis of atrial fibrillation, heart failure, and hypertension were seen within a week of being discharged. Patients with significant comorbidities were less likely to obtain follow-up care, as were those with a family physician who was remunerated via primarily capitation methods.
A new lab-based aerosol jet fog (ajFOG) deposition system with an atomizer consisting of two opposing jets located within the deposition chamber is introduced and its capabilities are examined. The unique opposing configuration of the atomizer enables the formation of a highly uniform fog even from low volatility precursors. Aluminum oxide phosphate (AlPO) thin films were deposited onto Si wafers at room temperature and sub-atmospheric pressure by using an aqueous precursor. Films were characterized by spectroscopic ellipsometry, x-ray diffraction and reflectivity, scanning electron microscopy, and metal/oxide/semiconductor (MOS) capacitor electrical measurements. Film thickness uniformity, density, surface roughness, and charge transport mechanisms were found to be comparable to spin-coated thin films deposited using the same precursor, demonstrating the effectiveness of this aerosol technique. A process model was developed to predict film thickness as a function of precursor concentration, exposure time, fog settling time, and number of exposures.
A quarter of humanity today lives without access to any electricity and almost one-half still depends on solid fuels such as unprocessed biomass, coal, or charcoal for its thermal needs. These people continue to suffer a multitude of impacts detrimental to their welfare. Most live in rural villages and urban slums in developing nations. Access to affordable modern energy carriers is a necessary, but insufficient step toward alleviating poverty and enabling the expansion of local economies.
Even among populations with physical access to electricity and modern fuels, a lack of affordability and reliable supplies limits the extent to which a transition to using these can occur. Those who can afford the improved energy carriers may still not be able to afford the upfront costs of connections or the conversion technology or equipment that makes that energy useful.
Beyond the obvious uses of energy for lighting, cooking, heating, and basic home appliances, uses for purposes that might bring economic development to an area are slow to emerge without institutional mechanisms in place that are conducive to fostering entrepreneurial activity and uses of energy for activities that can generate income. Without the expansion of energy uses to activities that generate income, the economic returns to energy providers are likely to remain unattractive in poor and dispersed rural markets.
Significant success has been achieved with small pilot projects to improve energy access in some rural areas and among poor communities in urban areas. But subsequently, less thought is focused on how to scale-up from these small pilot and demonstration projects to market development and meeting the needs of the larger population.
Octanethiol-stabilized Si nanocrystals, ranging from 2 to 8 nm in diameter, were synthesized in cyclohexane heated and pressurized above its critical point at temperatures ranging from 400°C to 500°C. The nanocrystals exhibit crystalline cores and photoluminesce with relatively high efficiencies. These nanocrystals are suitable for single particle spectroscopic measurements that reveal optical information about the individual chromophores that are buried in ensemble measurements. The sterically-stabilized Si nanocrystals emit with relatively narrow emission spectra at room temperature, characteristic of molecules.
Positron Annihilation Lifetime Spectroscopy (PALS) (1, 2) is a useful tool to pre-screen metal barrier integrity for Si-based porous low-k dielectrics. Pore size of low-k, thickness of metal barrier Ta, positronium (Ps) leakage from PALS, trench sidewall morphology, electrical test from one level metal (1LM) pattern wafer and Cu diffusion analysis were all correlated. Macro-porous low-k (pore size >= 200A) and large scale meso-porous low-k (>50∼200A) encounter both Ps leakage and Cu diffusion into low-k dielectric in the 0.25μmL/0.3μmS structures when using SEMATECH in-house PVD Ta 250A as barrier layer. For small scale meso-porous (>20∼50A) and micro-porous (<=20A) low-k, no Ps leakage and no Cu diffusion into low-k were observed even with PVD Ta 50A, which is proved also owing to sidewall densification to seal all sidewall pores due to plasma etch and ash. For future technology, smaller pore size of porous Si-based low-k (=< 50A) will be preferential for dense low-k like trench sidewall to avoid metal barrier integrity due to coverage problems from sidewall pores.
Annual revenue flow to developing countries for ecotourism could be as large as US$ 29 billion, providing an enormous financial incentive against habitat loss and exploitation. However, surprisingly little quantitative evidence exists on the profitability of the rainforest ecotourism sector, which determines the incentive and capacity of the sector to engage in conservation. A Peruvian rainforest ecotourism cluster generated US$ 11.6 million in 2005. The after-tax profit margin was at least 14% and has increased with tourist volume. High profitability, coupled with new legislation, has allowed operators to put 54 358 ha of rainforest near the new Interoceánica Sur highway under private management and to engage in conservation actions. A previously published microeconomic contract model of protected-areas management identifies two key features of rainforest tourism that link ecotourism to conservation: (1) tourists demand an immersive experience, which incentivizes the acquisition of large amounts of forest cover, and (2) institutional reforms have increased the expected effectiveness of conservation actions. In Peru, these conditions appear to be met, so that profits from ecotourism can combine with new land tenure rights to create a governance structure within which the industry can act as an independently financed partner to the conservation community.
The effects of the H+. C+. N+, F+, and Ne+ (25–200 keV)ion irradiations have been investigated by means of SEM, room temperature resistance measurement and aqueous degradation test. The room temperature resistance increases exponentially with irradiation doses. At lower dose, the annealing process is dominent, while at higher dose, the resistance increasing process is dominent. A reduction in the thickness induced by ion irradiation has been observed. The aqueous experiment shows that passing current will speed up the degredation and N+ implantations can increase the resistance of the YBCO thin film against attack by water.
Photoexcitation of the Si electronic subsystem during ion implantation was found to be able to control radiation damage accumulation. Conditions when additional light illumination during ion bombardment suppresses radiation defect formation are determined. The model of effect observed taking into account recombination of nonequilibrium electron and holes is proposed. Coefficient between the change in amount of damage accumulated and the rate of nonequilibrium charge carriers generation is estimated.
Low-pressure chemical vapor deposition of polycrystalline silicon and silicon dioxide in a lampheated cold-wall rapid thermal processor have been investigated. Silicon dioxide films have been deposited by thermal decomposition of tetraethylorthosilicate known as TEOS. The technique can be used for rapid deposition of good quality thick passivation layers at moderate temperatures. Polycrystalline silicon depositions have been accomplished using silane (SiH4) diluted in argon as the reactive gas. Surface roughness and resistivity of the films deposited at temperatures above 700°C are comparable in quality to films deposited in a conventional LPCVD reactor at 610°C. In this temperature range, deposition rates as high as 4000Å/min can be obtained.
GaN film grown on Si substrate with AlN/AlxGa1−xN buffer is studied by low pressure metal organic chemical vapor deposition (MOCVD) method. The AlxGa1−xN film with Al composition varying from 0∼ 0.66 was used. The correlation of the Al composition in the AlxGa1−xN film with the stress of the GaN film grown was studied using high resolution X-ray diffraction including symmetrical and asymmetrical ω/2θscans and reciprocal space maps. It is found that with proper design of the Al composition in the AlxGa1−xN buffer layer, crack-free GaN films can be successfully grown on Si (111) substrates using AlN and AlxGa1−xN buffer layers.
Bulk silicon-germanium (SiGe) alloys and two SiGe thick films (4 and 5 μm) on Si wafers were tested with the electron probe microanalyzer (EPMA) using wavelength dispersive spectrometers (WDS) for heterogeneity and composition for use as reference materials needed by the microelectronics industry. One alloy with a nominal composition of Si0.86Ge0.14 and the two thick films with nominal compositions of Si0.90Ge0.10 and Si0.75Ge0.25 on Si, evaluated for micro- and macroheterogeneity, will make good microanalysis reference materials with an overall expanded heterogeneity uncertainty of 1.1% relative or less for Ge. The bulk Ge composition in the Si0.86Ge0.14 alloy was determined to be 30.228% mass fraction Ge with an expanded uncertainty of the mean of 0.195% mass fraction. The thick films were quantified with WDS-EPMA using both the Si0.86Ge0.14 alloy and element wafers as reference materials. The Ge concentration was determined to be 22.80% mass fraction with an expanded uncertainty of the mean of 0.12% mass fraction for the Si0.90Ge0.10 wafer and 43.66% mass fraction for the Si0.75Ge0.25 wafer with an expanded uncertainty of the mean of 0.25% mass fraction. The two thick SiGe films will be issued as National Institute of Standards and Technology Reference Materials (RM 8905).
The Working Group FITS (WG-FITS) is the international control authority for the Flexible Image Transport System (FITS) data format. The WG-FITS was formed in 1988 by a formal resolution of the IAU XX General Assembly in Baltimore (MD, USA), 1988, to maintain the existing FITS standards and to approve future extensions to FITS.
Ecotourism can capture biodiversity values and provide incentives for conservation, and many integrated conservation and development projects include an ecotourism component. One key assumption behind this strategy is that ecotourism businesses can achieve financial viability. This paper presents a financial case study of the well-known community-based ecotourism lodge ‘Casa Matsiguenka’, owned by an indigenous Matsigenka population in Manu National Park (Peru), only the second such project to be thoroughly analysed in the literature. Built and financed from 1997 to 2003 with German official aid, the lodge's revenues have only just exceeded operating costs and have not covered the costs of infrastructure replacement, thereby failing to secure long-term business sustainability. Wages and income from handicraft sales have covered about a third of individual cash needs in the two participating communities, but communal income from lodge operating profits (for example to pay for community infrastructure, health care or education) has been minimal. The lodge's difficulties are attributed largely to a flawed business plan in which the lodge has sold its services to its own competitors, a group of ecotourism agencies that have used their lobbying power to create a cartel in Manu. In a narrow analysis, the return on investment for this project has been approximately one-third of what could have been achieved to date by merely investing the start-up grant monies in a bank account and paying the interest directly to the Matsigenka communities in exchange for conservation actions. Broader analysis indicates the modest income and slow pace of business so far has permitted gradual social and economic adaptation on the part of culturally conservative indigenous communities. Moreover, the lodge project has generated processes of social and political organization, and sustained positive contact with Peruvian national society, which can be counted among its successes. The lodge has helped produce dialogue between the Park administration and the Matsigenka communities, a process that could ultimately result in co-management agreements that help to resolve people-park conflicts in the Park.
The business meeting began with a brief review of the current rules and procedures of the WG, which are documented on the WG web page. Four regional FITS committees have been established by the WG, covering North American, Europe, Japan, and Australian/New Zealand, to provide advice to the WG on pending proposals. While it is recognized that this committee structure might need to be revised to provide representation to other regions, the current system is working well, and there were no motions to make any changes at this time.
Injured survivors of individual and mass trauma are at risk for developing post-traumatic stress disorder (PTSD). Few investigations have assessed PTSD after injury in large samples across diverse acute care hospital settings.
A total of 2931 injured trauma survivors aged 18–84 who were representative of 9983 in-patients were recruited from 69 hospitals across the USA. In-patient medical records were abstracted, and hospitalized patients were interviewed at 3 and 12 months after injury. Symptoms consistent with a DSM-IV diagnosis of PTSD were assessed with the PTSD Checklist (PCL) 12 months after injury.
Approximately 23% of injury survivors had symptoms consistent with a diagnosis of PTSD 12 months after their hospitalization. Greater levels of early post-injury emotional distress and physical pain were associated with an increased risk of symptoms consistent with a PTSD diagnosis. Pre-injury, intensive care unit (ICU) admission [relative risk (RR) 1·17, 95% confidence interval (CI) 1·02–1·34], pre-injury depression (RR 1·33, 95% CI 1·15–1·54), benzodiazepine prescription (RR 1·46, 95% CI 1·17–1·84) and intentional injury (RR 1·32, 95% CI 1·04–1·67) were independently associated with an increased risk of symptoms consistent with a PTSD diagnosis. White injury survivors without insurance demonstrated approximately twice the rate of symptoms consistent with a diagnosis of PTSD when compared to white individuals with private insurance. By contrast, for Hispanic injury survivors PTSD rates were approximately equal between uninsured and privately insured individuals.
Nationwide in the USA, more than 20% of injured trauma survivors have symptoms consistent with a diagnosis of PTSD 12 months after acute care in-patient hospitalization. Coordinated investigative and policy efforts could target mandates for high-quality PTSD screening and intervention in acute care medical settings.
The gettering of transition metals in silicon presents new challenges since older schemes such as internal gettering cease to be effective with newer technologies. The oxygen concentration in active regions is also a matter of concern when denuding cycles are not employed. Implantation of a deep layer of boron is a promising technique. The effects of boron implants at 1.7 MeV in the dose range 1014 – 1015 at./cm2 were studied with regard to the redistribution of both Fe and 0 after a thermal cycle. Fe was introduced onto the front surface of wafers by deposition after boron implantation. The redistribution of these species was monitored through SIMS depth profiles. In addition, diffusion length measurements from the back surface of the wafers were employed as a new means of assessing Fe gettering. In general there is a lowering of the surface oxygen concentration that increases with dose, or with temperature in the range 850-1000°C. The oxygen concentration can be lowered to a level comparable to denuded wafers at the upper end of this range. The amount of Fe gettering is higher after 850°C than after 1000°C at a given dose. Diffusion length measurements correlate well with SIMS data and provide a convenient method of investigating Fe gettering. This study has demonstrated the feasibility of optimizing a combination of dose and temperature for the gettering of Fe and the lowering of surface oxygen concentration to an acceptable level for device fabrication.
Several authors have suggested that ecotourism can enhance the value of intact wildlands and thereby promote conservation. Two rainforest lodges dating from the 1970s and located in southeastern Amazonian Perú have been held up as early success stories in tourism-driven conservation, but a more recent assessment reveals that both lodges have since lost their rainforest reserves to encroachment. One of the major reasons for failure was that the national land laws in effect at the time did not allow the purchase of land titles. Recently, Perú has instituted a process for the purchase of land titles in the rainforest. One lodge has used the new land tenure laws with some success to create a rainforest reserve. The very attempt to buy land for purposes of conservation can promote encroachment and land-buying speculation, and the lodge's current agreement with its neighbours to provide a school in exchange for non-encroachment is fraught with moral hazards and appears unstable over the long term. Tourism can promote conservation primarily at the national level, and ecotourism projects in the Peruvian Amazon can stabilize land-use patterns at least in the short term. However, the conservation of habitat over the long-term will rest primarily on the ability of the State to enforce a consistent land use policy with regard to land tenure and Park protection.
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