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1.
Proc Natl Acad Sci U S A ; 116(51): 25497-25502, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31792173

RESUMO

Understanding electricity consumption and production patterns is a necessary first step toward reducing the health and climate impacts of associated emissions. In this work, the economic input-output model is adapted to track emissions flows through electric grids and quantify the pollution embodied in electricity production, exchanges, and, ultimately, consumption for the 66 continental US Balancing Authorities (BAs). The hourly and BA-level dataset we generate and release leverages multiple publicly available datasets for the year 2016. Our analysis demonstrates the importance of considering location and temporal effects as well as electricity exchanges in estimating emissions footprints. While increasing electricity exchanges makes the integration of renewable electricity easier, importing electricity may also run counter to climate-change goals, and citizens in regions exporting electricity from high-emission-generating sources bear a disproportionate air-pollution burden. For example, 40% of the carbon emissions related to electricity consumption in California's main BA were produced in a different region. From 30 to 50% of the sulfur dioxide and nitrogen oxides released in some of the coal-heavy Rocky Mountain regions were related to electricity produced that was then exported. Whether for policymakers designing energy efficiency and renewable programs, regulators enforcing emissions standards, or large electricity consumers greening their supply, greater resolution is needed for electric-sector emissions indices to evaluate progress against current and future goals.

2.
Eur J Pediatr ; 180(4): 1307-1312, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33067712

RESUMO

Clinical psychology intervention in paediatric gastroenterology is vital given the biopsychosocial aetiology of paediatric functional gastrointestinal disorders, and the psychological impact of chronic conditions. The aim was to assess the availability and benefit of clinical psychology in paediatric gastroenterology across the UK and Germany. A retrospective assessment of referrals (n = 936 referrals) to clinical psychology was performed at our tertiary paediatric gastroenterology centre between 2010 and 2018. The availability of clinical psychologists and outcome of psychology intervention for children with functional abdominal pain were also assessed. Access to clinical psychology across the UK and Germany was assessed using an online questionnaire. We observed a substantial rise in the number of clinical psychology referrals between 2010 and 2018. Increasing demand was not matched by sufficient increase in availability of clinical psychology, leading to longer waiting times. A major benefit of clinical psychology intervention was highlighted with 95% of patients (n = 20) reporting a significant reduction in symptoms. Of the 12 centres who responded, 11 centres have direct access to clinical psychology with a mean of 13% of patients requiring psychology referrals annually.Conclusion: Despite evidence of its benefit and increasing demand, there is insufficient access to clinical psychological services, highlighting the urgent need to address this important issue. What is known: • The biopsychosocial pathophysiology of functional gastrointestinal disorders involves a disordered brain-gut interaction, which emphasizes the close link between psychological factors and altered gut function. • Psychological intervention, as an adjunct to medical treatment, improves outcomes in paediatric patients with gastrointestinal (GI) disease such as functional gastrointestinal disorders and inflammatory bowel diseases What is new: • There is a rising number of referrals from paediatric gastroenterology to clinical psychology in our centre which is not met by a sufficient increase in the availability of clinical psychologists. Similarly, access to clinical psychological services is lacking in several paediatric gastroenterology centres in the UK and Germany. • Strategic action is required to address this important gap in the care of children suffering from GI diseases.


Assuntos
Gastroenterologia , Gastroenteropatias , Psicologia Clínica , Criança , Gastroenteropatias/terapia , Alemanha , Humanos , Estudos Retrospectivos
3.
Proc Natl Acad Sci U S A ; 115(13): 3290-3295, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29531081

RESUMO

Bioenergy with carbon capture and storage (BECCS) is a negative-emissions technology that may play a crucial role in climate change mitigation. BECCS relies on the capture and sequestration of carbon dioxide (CO2) following bioenergy production to remove and reliably sequester atmospheric CO2 Previous BECCS deployment assessments have largely overlooked the potential lack of spatial colocation of suitable storage basins and biomass availability, in the absence of long-distance biomass and CO2 transport. These conditions could constrain the near-term technical deployment potential of BECCS due to social and economic barriers that exist for biomass and CO2 transport. This study leverages biomass production data and site-specific injection and storage capacity estimates at high spatial resolution to assess the near-term deployment opportunities for BECCS in the United States. If the total biomass resource available in the United States was mobilized for BECCS, an estimated 370 Mt CO2⋅y-1 of negative emissions could be supplied in 2020. However, the absence of long-distance biomass and CO2 transport, as well as limitations imposed by unsuitable regional storage and injection capacities, collectively decrease the technical potential of negative emissions to 100 Mt CO2⋅y-1 Meeting this technical potential may require large-scale deployment of BECCS technology in more than 1,000 counties, as well as widespread deployment of dedicated energy crops. Specifically, the Illinois basin, Gulf region, and western North Dakota have the greatest potential for near-term BECCS deployment. High-resolution spatial assessment as conducted in this study can inform near-term opportunities that minimize social and economic barriers to BECCS deployment.


Assuntos
Bioengenharia , Biomassa , Dióxido de Carbono/isolamento & purificação , Sequestro de Carbono , Carbono/metabolismo , Monitoramento Ambiental , Biodegradação Ambiental , Biocombustíveis , Mudança Climática , Conservação de Recursos Energéticos , Humanos , Estados Unidos
4.
J Synchrotron Radiat ; 22(2): 452-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25723947

RESUMO

There is high demand for efficient, robust and automated routines for tomographic data reduction, particularly for synchrotron data. Registration of the rotation axis in data processing is a critical step affecting the quality of the reconstruction and is not easily implemented with automation. Existing methods for calculating the center of rotation have been reviewed and an improved algorithm to register the rotation axis in tomographic data is presented. The performance of the proposed method is evaluated using synchrotron-based microtomography data on geological samples with and without artificial reduction of the signal-to-noise ratio. The proposed method improves the reconstruction quality by correcting both the tilting error and the translational offset of the rotation axis. The limitation of this promising method is also discussed.

5.
iScience ; 27(7): 110398, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39092179

RESUMO

The increasing cooling needs in commercial buildings, exacerbated by climate change, warrant immediate attention. These buildings, characterized by their long lifespans and slow stock turnover, change consumption over time. This study develops simple, interpretable data-driven models using weather- and occupancy-related features to analyze the cooling in different types of co-located buildings. Over five years, our models effectively predict the cooling load across buildings with R-squared values of 81%-87%. Factoring out geography-driven differences, we identify strong heterogeneity within and across different buildings. The average estimated base load cooling varies between 0.50 and 4.4 MJ/m2/day across buildings, with healthcare facilities exhibiting the highest loads and residences the lowest. Consumption increases by 7.6%-9.8% for every 1°C increase in mean daily outside temperature, with up to 27% reductions in offices on weekends. These insights enable diagnoses of inefficiencies, post-retrofitting performance tracking, and proactive planning for climate-related impacts.

6.
Environ Sci Technol ; 47(7): 3482-9, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23441588

RESUMO

A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.


Assuntos
Eletricidade , Indústrias , Internacionalidade , Efeito Estufa , Indústrias/economia , Termodinâmica
7.
Environ Sci Technol ; 45(9): 4179-86, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21466184

RESUMO

CO2 was injected into a coal fire burning at a depth of 15 m in the subsurface in southwestern Colorado, USA. Measurements were made of the ¹³CO2 isotopic signature of gas exhaust from an observation well and two surface fissures. The goal of the test was to determine (1) whether CO2 with a distinct isotopic signature could be used as a tracer to identify flow pathways and travel times in a combustion setting where CO2 was present in significant quantities in the gases being emitted from the coalbed fire, and (2) to confirm the existence of a self-propagating system of air-intake and combustion gas exhaust that has been previously proposed. CO2 was injected in three separate periods. The ¹³CO2 isotopic signature was measured at high frequency (0.5 Hz) before, during, and after the injection periods for gas flowing from fissures over the fire and from gas entering an observation well drilled into the formation just above the fire but near the combustion zone. In two cases, a shift in the isotopic signature of outgassing CO2 provided clear evidence that injected CO2 had traveled from the injection well to the observation point, while in a third case, no response was seen and the fissure could not be assumed to have a flowpath connected with the injection well. High-frequency measurements of the ¹³CO2 signature of gas in observation wells is identified as a viable technique for tracking CO2 injected into subsurface formations in real-time. In addition, a chimney-like coupled air-intake and exhaust outlet system feeding the combustion of the coal seam was confirmed. This can be used to further develop strategies for extinguishing the fire.


Assuntos
Dióxido de Carbono/análise , Incêndios , Ar/análise , Isótopos de Carbono/análise , Colorado , Gases/análise , Estados Unidos
8.
Nat Commun ; 11(1): 206, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924780

RESUMO

Leads are a key feature of the Arctic ice pack during the winter owing to their substantial contribution to the surface energy balance. According to the present understanding, enhanced heat and moisture fluxes from high lead concentrations tend to produce more boundary layer clouds. However, described here in our composite analyses of diverse surface- and satellite-based observations, we find that abundant boundary layer clouds are associated with low lead flux periods, while fewer boundary layer clouds are observed for high lead flux periods. Motivated by these counterintuitive results, we conducted three-dimensional cloud-resolving simulations to investigate the underlying physics. We find that newly frozen leads with large sensible heat flux but low latent heat flux tend to dissipate low clouds. This finding indicates that the observed high lead fractions likely consist of mostly newly frozen leads that reduce any pre-existing low-level cloudiness, which in turn decreases downwelling infrared flux and accelerates the freezing of sea ice.

9.
Data Brief ; 25: 104249, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31489346

RESUMO

This data article provides detailed explanation and data on CO2/water coreflooding experiments performed on nine sandstone rock cores. Refer to the research article "Predicting CO2 Residual Trapping Ability Based on Experimental Petrophysical Properties for Different Sandstone Types" [1] for data interpretation. The reader can expect to find experimental conditions including temperature, pressure, fluid pair types, as well as flow rates. Furthermore, the raw CT images and the processed three-dimensional (3D) voxel-level porosity, permeability, and CO2 saturation maps for each of the nine sandstone samples are also supplied.

10.
Science ; 360(6396)2018 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-29954954

RESUMO

Some energy services and industrial processes-such as long-distance freight transport, air travel, highly reliable electricity, and steel and cement manufacturing-are particularly difficult to provide without adding carbon dioxide (CO2) to the atmosphere. Rapidly growing demand for these services, combined with long lead times for technology development and long lifetimes of energy infrastructure, make decarbonization of these services both essential and urgent. We examine barriers and opportunities associated with these difficult-to-decarbonize services and processes, including possible technological solutions and research and development priorities. A range of existing technologies could meet future demands for these services and processes without net addition of CO2 to the atmosphere, but their use may depend on a combination of cost reductions via research and innovation, as well as coordinated deployment and integration of operations across currently discrete energy industries.

12.
Clin Child Psychol Psychiatry ; 20(3): 472-85, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24711586

RESUMO

The use of psychosocial forums in paediatric settings has been recommended as a means of providing psychological consultancy. However, no research has explored staff perceptions of these meetings or whether they have a positive impact on patient care. In this study, six members of a paediatric gastroenterology multidisciplinary team were interviewed about their experience of a weekly psychosocial forum using a qualitative approach. The data revealed that staff regarded the forum as an essential and useful part of the service. Staff reported a number of benefits to their clinical work as a result of attending the forum, in addition to the general benefits of having a clinical psychologist available to see patients. However, staff also made recommendations for improving the forum. The results suggest that psychosocial forums may provide an efficient means of delivering specialist psychological consultation for patients with psychological difficulties, in line with Department of Health recommendations for paediatric services. Future research should aim to investigate the effectiveness of psychosocial forums in different settings and to establish the cost-effectiveness of these meetings.


Assuntos
Atitude do Pessoal de Saúde , Gastroenterologia , Pediatria , Psicologia Clínica , Encaminhamento e Consulta , Humanos , Equipe de Assistência ao Paciente , Pesquisa Qualitativa
13.
Sci Rep ; 5: 10635, 2015 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-26039795

RESUMO

The elevated level of atmospheric carbon dioxide (CO2) has caused serious concern of the progression of global warming. Geological sequestration is considered as one of the most promising techniques for mitigating the damaging effect of global climate change. Investigations over wide range of length-scales are important for systematic evaluation of the underground formations from prospective CO2 reservoir. Understanding the relationship between the micro morphology and the observed macro phenomena is even more crucial. Here we show Synchrotron based X-ray micro tomographic study of the morphological buildup of Sandstones. We present a numerical method to extract the pore sizes distribution of the porous structure directly, without approximation or complex calculation. We have also demonstrated its capability in predicting the capillary pressure curve in a mercury intrusion porosimetry (MIP) measurement. The method presented in this work can be directly applied to the morphological studies of heterogeneous systems in various research fields, ranging from Carbon Capture and Storage, and Enhanced Oil Recovery to environmental remediation in the vadose zone.

15.
Science ; 344(6191): 1431, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24970054
16.
Appl Opt ; 42(3): 332-41, 2003 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-12570253

RESUMO

In this fourth of a series of papers that describe long-term cloud research at the Facility for Atmospheric Remote Sensing at Salt Lake City, Utah, an approximately 10-year record of polarization lidar and photographic observations is analyzed to characterize the occurrence of optical displays in our local varieties of midlatitude cirrus clouds. The frequencies of occurrence of various types of halo, arc, and corona displays are evaluated according to their appearance and longevity over nominal 1-h observation periods and to the meteorological source of the cirrus. We find that complex halo-arc displays are rare at our locale and that even the so-called common 22 degree halo occurs infrequently as a complete long-lived ring. For example, only approximately 6% of the 1561-h daytime cirrus periods have bright and prolonged 22 degree halos, although a total of 37.3% have some indications of this halo, even if they are brief and fragmentary. Other fairly frequent features are the 22 degree upper tangent arc (8.6%), 22 degree parhelia (8.5%), and solar corona (7.2%). Of the optical displays observed, 83.6% are refraction based, only 1.9% are due to reflection phenomena, and a surprising 15.4% are caused by diffraction. Complex halo-arc displays are disproportionally associated with cirrus formed in tropical or subtropical airflow and also contain more horizontally oriented planar ice crystals. Lidar linear depolarization ratios from a subset of vivid displays show significant differences between halo- and the corona-producing cirrus, reflecting the effects of particle shape. Halos are associated with relatively warm cirrus that contain randomly and horizontally oriented planar ice crystals, whereas the colder corona cirrus produce much stronger depolarization from crystals too small to be uniformly oriented. Comparisons are made with available information from other locales, and we attempt to explain the geographical differences in terms of basic cirrus cloud processes.

17.
Environ Sci Technol ; 37(11): 2415-20, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12831026

RESUMO

Pilot-scale tests for the land disposal of Se-enriched sediments from the San Luis Drain were performed in the San Joaquin Valley, California. Three test plots were instrumented and monitored on a dirt-road embankment near the sediment source area, providing an opportunity to measure Se oxidation and solubilization rates over a period of 2-3 yr. Soil, soil water, and groundwater data indicated that the amendment did not cause movement of dissolved Se below a depth of 15 cm. The low permeability of underlying sediments and the overall low Se solubility limit Se movement toward the groundwater table. Selenium remained in reduced forms and largely immobile at this site, although in-situ Se oxidation was measurable. Soluble Se concentrations increased from less than 0.5% to approximately 2.5% in the first 207 d following sediment application. Minor Se solubilization occurred after 439 and 704 d. Changes in Se fractionation measured using sequential extractions and Se speciation based on X-ray spectroscopy (XANES) results were in qualitative agreement. XANES results indicated initially rapid oxidation of organo-Se and/or elemental Se to selenite during the first 207 d, followed by minor oxidation after 439 d. Further solubilization of the Se inventory is anticipated, but at a low rate of 1-2% per year, comparable to rates measured in other studies.


Assuntos
Sedimentos Geológicos/química , Selênio/química , Poluentes do Solo/análise , Oxirredução , Solubilidade
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