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Global urbanization drastically reshapes the land–atmosphere interactions, biogeochemical cycles, and ecosystems in the integrated earth system. Urban trees are used extensively for providing desirable ecosystem services, especially to mitigate elevated thermal stress in cities. Urban trees differ markedly from their natural counterparts in the physiology due to their close interactions with anthropogenic stressors. Here we present the cooling capacity of urban trees in response to thermal extremes in cities of the contiguous United States. The cooling capacity is quantified as the surface cooling rate, which is expressed as the negative ratio of land surface temperature (LST) changes to fractional tree cover (FTC) changes, i.e., –ΔLST/ΔFTC. Results show that the surface cooling rate is dominated by plant transpiration up to 1.336 °C per percentage of FTC in heat waves; its temperature dependence remarkably resembles the thermodynamic liquid-water-vapor equilibrium. Urban trees also exert pseudo cooling effect in cold waves in contrast to the anthropogenic heat emission. The average surface cooling rate in cold waves is 0.022 °C per percentage of FTC, which is much smaller than that in heat waves (0.202 °C per percentage of FTC). The enhanced cooling capacity of urban trees will enable their provision of better ecosystem services to the urban environment for projected future increase of extreme heat. Unlabelled Image • The surface cooling rate of urban trees during heat and cold waves is quantified. • Temperature dependence of tree cooling resembles the phase equilibrium of water. • The cooling of urban trees is dominated by plant transpiration in heat waves. • The synthetic cooling of cities is regulated by anthropogenic heat in cold waves. • Urban trees are ahead of the global change responses than their rural counterparts. [ABSTRACT FROM AUTHOR]

Passive cooling devices take advantage of the partially transparent properties of the atmosphere in the longwave spectral band from 8 to 13 μm (the so-called "atmospheric window") to reject radiation to outer space. Spectrally designed thermophotonic devices have raised substantial attention recently for their potential to provide passive and carbon-free alternatives to air conditioning. However, the level of transparency of the atmospheric window depends on the local content of water vapor in the atmosphere and on the optical depth of clouds in the local sky. Thus, the radiative cooling capacity of solar reflectors not only depends on the optical properties of their surfaces but also on local meteorological conditions. In this work, detailed radiative cooling resource maps for the contiguous United States are presented with the goal of determining the best climates for large-scale deployment of passive radiative cooling technologies. The passive cooling potential is estimated based on ideal optical properties, i.e., zero shortwave absorptance (maximum reflectance) and blackbody longwave emittance. Both annual and season-averaged maps are presented. Daytime and nighttime cooling potential are also computed and compared. The annual average cooling potential over the contiguous United States is 50.5 m−2. The southwestern United States has the highest annual averaged cooling potential, over 70 W m−2, due to its dry and mostly clear sky meteorological conditions. The southeastern United States has the lowest potential, around 30 W m−2, due to frequent humid and/or overcast weather conditions. In the spring and fall months, the Arizona and New Mexico climates provide the highest passive cooling potential, while in the summer months, Nevada and Utah exhibit higher potentials. Passive radiative cooling is primarily effective in the western United States, while it is mostly ineffective in humid and overcast climates elsewhere. [ABSTRACT FROM AUTHOR]

Heat conduction load test is a main and tough issue in the complex and huge general atom (GA) feeder system cold test. The GA feeder system is a superconducting system connects from the room temperature power supply system to the 4.5-K busbar of the magnet, supply 52 kA current and cryogenic provisions to the central solenoid magnet (CSM) coil, used for International Thermonuclear Experimental Reactor CSM magnet test at General Atomics Company, San Diego, CA, USA. This system have been developed and constructed at the Institute of Plasma Physics, Chinese Academy of Sciences, and completed the full cold test before transferred to the USA. In all the cold test items, the requirement of overall heat load 68 W is a big challenge, for its many leakage heat sources and cooling circuits: high temperature superconducting current lead, vacuum barrier, busbars, pipes, supports, etc. In order to get the steady results, many efforts were took to achieve the required value, such as reduce the inlet pressure of the 5-K loop as much as possible, minimize the flow rate of different 5-K cooling circuits, and at the same time, a dedicated program was developed to online calculate the density and the heat load while monitoring and analyzing the heat load. This paper will give a detail description of the 5-K overall heat load measurement. [ABSTRACT FROM AUTHOR]

A combined cooling, heating, and power system based on biomass gasification is modeled via experiment and its performance is evaluated. The system operation is simulated using load data of small offices located in different climate zones in the U.S. The operation strategy comprises following the electric load (FEL) and following the thermal load (FTL). Based on the operation data, energetic, economic, environmental, and overall performances of the system are evaluated. Results show that the annual integrated performance ( S whole ) of the system ranges from 0.229 to 0.473 in FEL mode and from 0.067 to 0.457 in FTL mode, in different regions. The system has a better performance in FEL mode, and is more attractive to install in the regions with more thermal load. Furthermore, the match degree of heat to power ratio between load and output also has an effect on the system performance. Sensitivity analysis shows that the system performance is more sensitive to the cost of biomass, cost of grid electricity and CO 2 emission rate of the grid in both modes, and COP of thermally activated chiller in FTL mode. By changing the above-mentioned parameters, S whole can be improved by up to 13.7%, 8.2%, 11.0%, and 19.7% respectively. [ABSTRACT FROM AUTHOR]

This study analyses the influence of Personalized Conditioning (PC) systems for potential savings of energy, cost, and CO 2 emissions from commercial buildings in different U.S. cities. This analysis characterizes potential benefits from the deployment of PC systems during peak cooling hours for peak load shifting. PC systems deployed in coordination with the central building air conditioning systems could have a large-scale influence on a city's energy footprint. Specifically, portable PC systems that use Phase Change Materials (PCMs) for heat rejection, allow for heat absorption during the working hours and heat rejection during non-working hours typically coinciding with the off-peak (base) utility rates when the commercial building tend to be unoccupied. However, there are limiting factors for the potential energy and cost savings with the use of PC systems. Therefore, this study assesses the use of PC systems in addition to the existing building air conditioning system during cooling seasons. The assessment entails potential energy end-use savings for 7 major cities located in different geographical/climatic regions of the U.S. Furthermore, the study calculates potential cost savings based on the variations in the peak and off-peak (base) electricity rates for different local Time of Use (TOU) programs. This simulated evaluation of local building systems and utility programs allows for regional various on the city's energy footprint reduction to emerge. The analysis shows that midrise apartments are a better building type than office buildings for the deployment of PC systems during a cooling season. The cash savings per person for the deployment of PC systems for midrise apartments are $62/year, $40/year, and $37/year for Honolulu, NY City, and Phoenix, respectively. The simulations also showed that using extended setpoint temperatures could reduce the CO 2 emissions up to 21.4% per year. [ABSTRACT FROM AUTHOR]

Aim: Therapeutic hypothermia is standard of care in term infants with moderate-to-severe hypoxic-ischaemic encephalopathy (HIE). The goal of this survey was to explore the attitudes of U.S. neonatologists caring for infants with HIE who fall outside of current guidelines.Methods: Case-based survey administered to members of the Section on Neonatal-Perinatal Medicine of the American Academy of Pediatrics.Results: A total of 447 responses were analysed, a response rate of 19%. We found significant variability amongst U.S. neonatologists with regard to the use of therapeutic hypothermia for infants with HIE who fall outside standard inclusion criteria. Scenarios with the most variability included HIE in a late preterm infant and HIE following a postnatal code. Provision of therapeutic hypothermia outside of standard guidelines was not influenced by number of years in practice, neonatal intensive care type (NICU) or NICU size.Conclusion: Significant variability in practice exists when caring for infants with HIE who do not meet standard inclusion criteria, emphasizing the need for continued and rigorous research in this area. [ABSTRACT FROM AUTHOR]

Passive envelope systems for building cooling are of great significance to achieve sustainable and low-energy buildings. Although promising advances in radiative sky cooling and enhanced glazing materials have been achieved recently, there still lacks performance evaluation on integrating these novel materials as passive building envelope systems for the cooling purpose. To this end, the study newly proposes a passive envelope system by synthetically incorporating radiative cooling roofs, colored cooling walls and thermally insulated glazing windows into a standard-compliant commercial building archetype. Comprehensive building thermal, energy, economic and environmental performance across a variety of typical climates in the United States was evaluated. The results were compared to the baseline model, in which the envelope properties are location-dependent and in accordance with ASHRAE Standard 90.1 (β = 0.3, β vis = 0.3, ε = 0.9 for exterior walls, β = 0.23–0.55, ε = 0.75–0.9 for roofs, and U = 1.9–2.8, SHGC = 0.23–0.38, VT = 0.253–0.418 for windows). The highly solar reflective and thermally emissive radiative cooling coating (β = 0.98, ε = 0.97) applied on roofs is able to achieve the cooling electricity savings ranging from 8.2% to 29.7% in response to different climate regions. In comparison, the colored (yellow) cooling paint (β = 0.72 , β vis = 0.59, ε = 0.95) applied on walls can achieve annual cooling energy savings regionally from 3.5% to 9.3%. Besides, the thermally insulated windows with the improved visual comfort can save cooling energy from −2.1% to 3.7%. From the maximized cost saving perspective, the optimal design schemes of passive cooling building envelopes for each region were accordingly determined, by which the net cost saving ranges from 0.03 to 2.13 $/(m2·year) in response to climate variability. Notably, the optimal building envelopes regionally correspond to the net avoided CO 2 emissions ranging from 0.11 to 16.72 kg/(m2·year)), indicating the noticeable carbon neutral potential induced by the proposed passive envelope system. This research is an effort to provide effective passive cooling envelope systems by combining the existing advanced cooling materials towards sustainable and energy-efficient buildings. [ABSTRACT FROM AUTHOR]

Data collected by the Centers for Disease Control and Prevention (CDC) show that improper cooling practices contributed to more than 500 foodborne illness outbreaks associated with restaurants or delis in the United States between 1998 and 2008. CDC's Environmental Health Specialists Network (EHS-Net) personnel collected data in approximately 50 randomly selected restaurants in nine EHS-Net sites in 2009 to 2010 and measured the temperatures of cooling food at the beginning and the end of the observation period. Those beginning and ending points were used to estimate cooling rates. The most common cooling method was refrigeration, used in 48% of cooling steps. Other cooling methods included ice baths (19%), room-temperature cooling (17%), ice-wand cooling (7%), and adding ice or frozen food to the cooling food as an ingredient (2%). Sixty-five percent of cooling observations had an estimated cooling rate that was compliant with the 2009 Food and Drug Administration Food Code guideline (cooling to 41°F [5°C] in 6 h). Large cuts of meat and stews had the slowest overall estimated cooling rate, approximately equal to that specified in the Food Code guideline. Pasta and noodles were the fastest cooling foods, with a cooling time of just over 2 h. Foods not being actively monitored by food workers were more than twice as likely to cool more slowly than recommended in the Food Code guideline. Food stored at a depth greater than 7.6 cm (3 in.) was twice as likely to cool more slowly than specified in the Food Code guideline. Unventilated cooling foods were almost twice as likely to cool more slowly than specified in the Food Code guideline. Our data suggest that several best cooling practices can contribute to a proper cooling process. Inspectors unable to assess the full cooling process should consider assessing specific cooling practices as an alternative. Future research could validate our estimation method and study the effect of specific practices on the full cooling process. [ABSTRACT FROM AUTHOR]

Spatial and temporal trends in temperature and precipitation extremes were investigated for the period 1948-2012 across the southeastern United States using 27 previously defined indices. Results show that regionwide warming in extreme minimum temperatures and cooling in extreme maximum temperatures occurred. The disproportionate changes in extreme daytime and nighttime temperatures are narrowing diurnal temperature ranges for most locations. The intensity and magnitude of extreme precipitation events increased overall, except for more easterly locations, particularly in South Carolina. These indices further show that warming in minimum temperatures has been pronounced most in summer and least in winter. Fall has become significantly wetter, while spring and summer have become drier, on average. Principal component analysis (PCA) was used to characterize a 'geography of extremes' based on temperature and precipitation extreme indices. The PCA based on temperature indices revealed two coherent western and eastern subregions that share common modes of variability in extremes. Precipitation indices resulted in a greater number of smaller, spatially coherent groups exhibiting similar modes of variability. This classification regime illustrates important variations in extremes that exist on subregional scales. These findings have relevance for established climate research institutes, local governments, resource managers, and community planners interested in the variability of extreme events throughout the region. [ABSTRACT FROM AUTHOR]

Global warming has drawn great attention in recent years because of its large impact on many aspects of the environment and human activities in buildings. One area directly affected by climate change is the energy consumption for heating and cooling. To quantify the impact, this study used the HadCM3 Global Circulation Model (GCM) to generate weather data for future typical meteorological years, such as 2020, 2050, and 2080, for 15 cities in the U.S. based on three CO 2 emission scenarios. The method was validated by comparing the projected TMY3 data using HadCM3 with the actual TMY3 data. By morphing method, the weather data was downscaled to hourly data for use in building energy simulations by EnergyPlus. Two types of residential buildings and seven types of commercial buildings were simulated for each of the 15 cities. This paper is the first to systematically study the climate change impact on various types of residential and commercial buildings in all seven climate zones in the U.S. through EnergyPlus simulations and provide weighted averaged results for national-wide building stock. We also identified geographical dependency of the impact of climate change on future energy uses. There would be a net increase in source energy consumption by the 2080s for climate zones 1–4 and net decrease in climate zones 6–7 based on the HadCM3 weather projection. Furthermore, this paper investigated natural ventilation performance in San Francisco, San Diego, and Seattle with improved natural ventilation model. We found that by the 2080s passive cooling would not be suitable for San Diego because of global warming, but it would still be acceptable for San Francisco and Seattle. [ABSTRACT FROM AUTHOR]

With vapor compression systems consuming a significant portion of the overall U.S. energy consumption each year, extensive efforts have been made toward the development of control strategies which aim to maximize system efficiency while providing the desired cooling. However, previous control strategies under-utilize a degree of freedom corresponding to the amount of refrigerant in the system, which is related to condenser subcooling and can significantly affect system efficiency. In this paper, an alternative system architecture, which utilizes a receiver and an additional electronic expansion valve, is used to provide independent control of condenser subcooling. Simulation and experimental results show there exists an optimal subcooling which maximizes system efficiency; however, this optimal subcooling changes with operating conditions. Therefore, extremum seeking control is implemented to find the optimal subcooling in an adaptive, model-free manner. Experimental results demonstrate a 9% increase in efficiency using the alternative architecture and extremum seeking control. [ABSTRACT FROM AUTHOR]

Highlights: [•] Climate change has spatially heterogeneous impact on heating and cooling energy and fuel uses in building sector. [•] Building energy and fuel uses are sensitive to other factors such as climate policy as well as climate change. [•] The 50-state building model provides both insights at the regional level and potentially better national-level estimates. [•] Climate change impact on building electricity use is critical, and needs to be incorporated in infrastructure planning. [ABSTRACT FROM AUTHOR]

Abstract: Heating, ventilation, and cooling (HVAC) accounts for 38% of building energy usage, and over 15% of all US energy usage, making it one of the nation's largest energy consumers. A number of projects have attempted to optimize the control of HVAC systems by minimizing the energy wasted in conditioning occupied buildings or rooms. Researchers have proposed systems that turn off air conditioners or heaters when a house is unoccupied, or put the system into an energy saving deep-setback mode when the occupants are inactive, such as when they are asleep. These approaches enable the retrofitting of centralized HVAC systems, that are widely used within the United States, to be more energy efficient. An area that has not been as well explored is the retrofitting of centralized HVAC systems to save energy when the residents are at home and awake. In this paper, we demonstrate how to use cheap, off-the-shelf sensors and actuators to retrofit a centralized HVAC system and enable the heating, or cooling, of rooms individually, in order to reduce waste caused by conditioning unoccupied rooms. We call this approach room-level zoning. Sensors detect room state and learned activity patterns are used to predict occupancy. Based on this information, unoccupied rooms drift away from a user defined comfortable temperature if occupants are less likely to use them in the near future while occupied rooms remain at a comfortable temperature. Thus, conditioning only the rooms with a high probability of occupancy to the setpoint saves energy by decreasing the load on the HVAC system. We implement a room-level zoning system, called Dual-Zone, in a 1400 square foot house by retrofitting an existing centralized HVAC system with wireless temperature sensors to monitor room-level temperature, motion sensors to monitor occupancy, and wirelessly actuatable dampers to control the flow of conditioned air through the house. Dual-Zone statically zones the house into two zones: one conditioned at night and the other conditioned during the day. Initial analysis indicates that this method has a 20.5% energy savings over the existing single-zoned thermostat during a 20 day evaluation. [Copyright &y& Elsevier]

Portions of the southern and southeastern United States, primarily Mississippi, Alabama, and Georgia, have experienced century-long (1895-2007) downward air temperature trends that occur in all seasons. Superimposed on them are shifts in mean temperatures on decadal scales characterized by alternating warm (1930s-1940s, 1990s) and cold (1900s; 1960s-1970s) regimes. Regional atmospheric circulation and SST teleconnection indices, station-based cloud cover and soil moisture (Palmer drought severity index) data are used in stepwise multiple linear regression models. These models identify predictors linked to observed winter, summer, and annual Southeastern air temperature variability, the observed variance (r) they explain, and the resulting prediction and residual time series. Long-term variations and trends in tropical Pacific sea temperatures, cloud cover, soil moisture and the North Atlantic and Arctic oscillations account for much of the air temperature downtrends. Soil moisture and cloud cover are the primary predictors of 59.6 % of the observed summer temperature variance. While the teleconnections, cloud cover and moisture data account for some of the annual and summer Southeastern cooling trend, large significant downward trending residuals remain in winter and summer. Comparison is made to the northeastern United States where large twentieth century upward air temperature trends are driven by cloud cover increases and Atlantic Multidecadal Oscillation (AMO) variability. Differences between the Northeastern warming and the Southeastern cooling trends in summer are attributable in part to the differing roles of cloud cover, soil moisture, the Arctic Oscillation and the AMO on air temperatures of the 2 regions. [ABSTRACT FROM AUTHOR]

Abstract: Global climate models (GCM) investigating the effects of land cover on climate have found that replacing extra-tropical forest with cropland promotes cooling. We compared cropland and forest surface temperatures across the continental United States in 16 cells that were approximately 1°×2° using 1km2 MODIS land surface temperature (LST) data and land cover from the 0.0009km2 National Land Cover Database (NLCD). We found that forest surface temperatures tended to be cooler than cropland surface temperatures. This relationship held for spring, summer, fall, and annually. In winter, cropland surface temperatures were cooler than forest surface temperatures except in the southeastern United States, where forest surface temperatures were also cooler in winter. The difference between cropland and forest surface temperatures was driven by daytime maxima, which tended to be twice as large as differences in nighttime minima. The dominance of daytime maxima was influenced by the degree of continentality. For cells on coastal margins or with a high proportion of inland lakes, differences between cropland and forest nighttime minima tended to be very small. In more continental locations croplands were noticeably cooler at night which often led to insignificant differences between cropland and forest average surface temperatures. [Copyright &y& Elsevier]

Abstract: The March 11, 2011 9.0 magnitude undersea megathrust earthquake off the coast of Japan and subsequent tsunami waves triggered a major nuclear event at the Fukushima Dai-ichi nuclear power station. At the time of the event, units 1, 2, and 3 were operating and units 4, 5, and 6 were in a shutdown condition for maintenance. Loss of cooling capacity to the plants along with structural damage caused by the earthquake and tsunami resulted in a breach of the nuclear fuel integrity and release of radioactive fission products to the environment. Fission products started to arrive in the United States via atmospheric transport on March 15, 2011 and peaked by March 23, 2011. Atmospheric activity concentrations of 131I reached levels of 3.0×10−2 Bqm−3 in Melbourne, FL. The noble gas 133Xe reached atmospheric activity concentrations in Ashland, KS of 17Bqm−3. While these levels are not health concerns, they were well above the detection capability of the radionuclide monitoring systems within the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty. [Copyright &y& Elsevier]

Abstract: A transition is occurring from DOE-2 to EnergyPlus in verification of residential energy code compliance, which increased the interest in the differences between these simulation tools. This study quantifies the differences between the slab-on-grade heat transfer models of DOE-2 (Winkelmann model, GCW) and EnergyPlus (the Slab model, GCS) programs for low rise energy code compliant residential buildings in hot-humid, hot-dry, temperate and cold climates of the U.S. The reliabilities of these models were also discussed by comparing them with the more detailed TRNSYS slab-on-grade model (GCT). The findings showed that, GCW calculated 10–13% higher total building loads than GCT did for identical slab-on-grade houses. GCS showed unconverged zone air temperatures and limitations for certain insulation configurations which resulted in 18–32% lower thermal loads than those calculated by GCT. When the zone air temperatures were converged, however, GCS calculated building loads within 9% of those calculated by GCT. This indicated a necessity of improvement in GCS to avoid erroneous results in residential energy code compliance calculations. [Copyright &y& Elsevier]

A comparison between energy performance, simulated by means of the EnergyPlus building simulation program, of two air systems (all air and fan coil) and radiant heating and cooling floors/ceilings is developed in this work for various European climates (Milan, Frankfurt, London, Madrid, Athens, Helsinki, and Moscow) and carried out on a reference building selected from among U.S. Department of Energy commercial building new construction benchmarks. The comparison is focused on the analysis of energy sources and CO2 emissions at equivalent thermal comfort quality levels in the various cases. The adoption of a radiant system, and of an appropriate primary energy system, always results in a reduction of energy sources exploited, of costs for energy wares purchased, and of carbon dioxide emissions. The greatest reductions can be achieved in climates where the energy demand for cooling is greater than the energy demand for heating. The article also focuses on the discussion of the procedure to be adopted when a comparison between air systems and radiant systems is implemented. [ABSTRACT FROM PUBLISHER]

Fossil fuel combustion and fertilizer application in the United States have substantially altered the nitrogen cycle, with serious effects on climate change. The climate effects can be short-lived, by impacting the chemistry of the atmosphere, or long-lived, by altering ecosystem greenhouse gas fluxes. Here we develop a coherent framework for assessing the climate change impacts of US reactive nitrogen emissions, including oxides of nitrogen, ammonia, and nitrous oxide (N2O). We use the global temperature potential (GTP), calculated at 20 and 100 y, in units of CO2 equivalents (CO2e), as a common metric. The largest cooling effects are due to combustion sources of oxides of nitrogen altering tropospheric ozone and methane concentrations and enhancing carbon sequestration in forests. The combined cooling effects are estimated at -290 to -510 Tg CO2e on a GTP20 basis. However, these effects are largely short-lived. On a GTP100 basis, combustion contributes just -16 to -95 Tg CO2e. Agriculture contributes to warming on both the 20-y and 100-y timescales, primarily through N2O emissions from soils. Under current conditions, these warming and cooling effects partially offset each other. However, recent trends show decreasing emissions from combustion sources. To prevent warming from US reactive nitrogen, reductions in agricultural N2O emissions are needed. Substantial progress toward this goal is possible using current technology. Without such actions, even greater CO2 emission reductions will be required to avoid dangerous climate change. [ABSTRACT FROM AUTHOR]

The viability of implementing renewable heating, cooling and electric systems for commercial buildings at Briarwood Club of Ankeny (BCOA), a golf course located in Ankeny, Iowa, USA, is addressed. A geothermal heat pump system with a horizontal loop field is the most viable renewable solution after incentives with an equity payback of less than 6 years and an internal rate of return (IRR) of 18.4% compared with conventional solutions. Solar thermal heating is not optimal for BCOA. Net metering of a 50 kW wind turbine is the most economical renewable electric solution after incentives with an equity payback of less than 13 years and an IRR of 8.6%; however, it is not attractive enough for BCOA to invest in. Solar photovoltaic systems are not as economically viable as wind turbines. However, zoning, incentives and net metering policy significantly affect the analysis, and the impact of these will be addressed. [ABSTRACT FROM PUBLISHER]

The cost savings potential of optimal passive thermal storage control were examined for day-ahead real time electricity rate structures. The operational strategies of three office building models were optimized in four US cities (Chicago, New York, Houston and Los Angeles) using price and weather data for the summer of 2008. Optimization of building thermal mass was conducted using a predictive optimal controller to define supervisory strategies in terms of building global cooling temperature setpoints. A global minimization algorithm determined optimal setpoint trajectories for each day divided into four distinct time periods. Cost savings were found to range from 0 to 14% depending on the building, climate, and characteristics of the rate signal. The best cost savings occurred for price spikes or cool nighttime temperatures. Moreover, it was found that low internal gains favoured a more flexible precooling strategy, while high internal gains coupled with low thermal mass resulted in poor precooling performance. [ABSTRACT FROM AUTHOR]

Abstract: This paper identifies the impact of thermostat strategies on heating and cooling energy consumptions in buildings, thus suggesting the importance of a database for understanding the effect of thermostat settings and for deciding energy-conscious strategies. Using computer simulation, diverse thermostat strategies – change of setback period, change of set-point temperature, and change of setback temperature – were tested parametrically in a typical USA single-family homes, located in two climate zones, namely cold (Detroit, Michigan) and hot-humid (Miami, Florida). Analysis revealed that heating and cooling systems were significant energy-consuming components in each climate zone. Accordingly, heating energy in cold climate zones and cooling energy in hot-humid climate zones have potential for matchingly significant saving. Diverse thermostat strategies (changes of setback period, of set-point, of setback temperature) demonstrated their obvious impacts on such saving. In the cold climate in particular, the heating system showed the most significant energy-saving effect via proper thermostat strategies. Proper setback period, set-point and setback temperature need to be established to achieve energy efficiency in residential buildings. [ABSTRACT FROM AUTHOR]

Our laboratory tested water samples used for cooling low-acid canned foods at a canning facility under investigation by the U.S. Food and Drug Administration. We used an enzyme-linked immunosorbent assay with digoxigenin-labeled antibodies (DIG-ELISA) and real-time PCR as screening methods and confirmed the presence of neurotoxin-producing Clostridium botulinum in the samples by mouse bioassay. [ABSTRACT FROM AUTHOR]

Purpose. The use of therapeutic hypothermia (TH) and its application in out of- hospital cardiac arrest patients are reviewed. Summary. Each year in the United States, an estimated 250,000-300,000 out-of-hospital cardiac arrests occur. Despite advances in prehospital care, the survival rate from TH is only 6-12%. In addition, survivors often have devastating consequences ranging from mild memory impairment to permanent brain damage. It is presumed that early induction of hypothermia produces an optimal effect, though benefits can still be achieved with late induction. Several methods have been devised to induce hypothermia, yet the optimal methods of cooling have not currently been determined. Major adverse effects of cooling include hemodynamic changes, cardiovascular complications, hyperglycemia, coagulopathy, increased rates of infection, fluid and electrolyte disorders, and shivering. The majority of these adverse effects can be prevented or minimized in the intensive care setting. In 2002, the use of TH-cooling the core body temperature to 32-34 °C-was supported by two landmark human studies, whose results led to the endorsement of TH by the American Heart Association and its increased use. The studies demonstrated that hypothermia results in favorable neurologic outcomes in patients suffering from out-of-hospital cardiac arrest due to ventricular fibrillation (VF), without increasing complications. Conclusion. TH is an effective strategy for improving neurologic outcomes of patients after out-of-hospital cardiac arrest due to VF. Further studies are needed to confirm the optimal time and methods for cooling to maximize the chance of complete neurologic recovery after cardiac arrest. [ABSTRACT FROM AUTHOR]

Data from observations and the Intergovernmental Panel on Climate Change (IPCC) twentieth-century climate change model [phase 3 of the Coupled Model Intercomparison Project (CMIP3)] simulations were analyzed to examine the decadal changes of the impact of ENSO on air temperature Tair and precipitation P over the United States. The comparison of composites for the early period (1915–60) and the recent period (1962–2006) indicates that cooling (warming) over the south and warming (cooling) over the north during ENSO warm (cold) winters have been weakening. The ENSO influence on winter P over the Southwest is strengthening, while the impact on P over the Ohio Valley is weakening for the recent decades. These differences are not due to the long-term trends in Tair or P; they are attributed to the occurrence of the central Pacific (CPAC) ENSO events in the recent years. The CPAC ENSO differs from the canonical eastern Pacific (EPAC) ENSO. The EPAC ENSO has a sea surface temperature anomaly (SSTA) maximum in the eastern Pacific. Enhanced convection extends from the date line to the eastern Pacific, with negative anomalies in the western Pacific. The atmospheric responses resemble a tropical Northern Hemisphere pattern. The wave train is consistent with the north–south Tair contrast over North America during the EPAC ENSO winters. The CPAC ENSO has enhanced convection in the central Pacific. The atmospheric responses show a Pacific–North American pattern. It is consistent with west–east contrast in Tair and more rainfall over the Southwest during the CPAC ENSO winters. [ABSTRACT FROM AUTHOR]

Abstract: A prolonged drought in the High Plains of Nebraska prompted the use of groundwater for cooling at the largest coal-fired power plant in the State. Prior to the drought, groundwater was used primarily for irrigation and the power plant relied exclusively on surface water stored in a nearby reservoir for cooling. Seepage from the reservoir system during the past ∼75a has resulted in the buildup of a large mound of water in the underlying unconfined aquifer. A well field was installed during the drought for the purpose of tapping the groundwater mound as a supplemental source of water for cooling. Concentrations of dissolved Cl− and indicate 65–100% of shallow groundwater and 0–100% of deep groundwater (saturated thickness ∼115m) in the immediate vicinity of the reservoir was from seepage out of the reservoir system. Hydrogen and O isotopic data indicate most surface-water seepage occurred in the late spring and early summer when reservoir stage was at its highest level. Tritium/3He apparent groundwater ages imply horizontal flow velocities from the reservoir were on the order of 60–600m/a. These diverse data provided information regarding the spatial distribution, timing, and rate of seepage from the reservoir that could not have been obtained from the available geologic, hydraulic head, and conductivity data. In particular, mixing fractions of surface water and regional groundwater in the aquifer could not have been determined using hydraulic information. Mixing fractions were of special interest in this study because of the management objective to maximize the capture of surface-water seepage in the cooling water wells. Groundwater-flow models developed as well-field management tools were calibrated using inverse modeling techniques and observations of groundwater age, surface-water flow, reservoir stage, and groundwater levels. The age data only accounted for 6 of the 2574 field observations used to calibrate the groundwater-flow models, yet they were among the most influential for refining estimates of hydraulic conductivity, recharge, and seepage from the reservoir. Results from this study demonstrate the benefits of using geochemical, isotopic, and age tracer data to develop conceptual and numerical models of groundwater flow for the purpose of water management. [Copyright &y& Elsevier]

Abstract: Optimization of combined cooling, heating, and power (CCHP) systems operation commonly focuses only on energy cost. Different algorithms have been developed to attain optimal utilization of CCHP units by minimizing the energy cost in CCHP systems operation. However, other outcomes resulting from CCHP operation such as primary energy consumption and emission of pollutants should also be considered during CCHP systems evaluation as one would expect these outcomes can be subject to regulation. This paper presents an optimization of the operation of CCHP systems for different climate conditions based on operational cost, primary energy consumption (PEC), and carbon dioxide emissions (CDE) using an optimal energy dispatch algorithm. The results for the selected cities demonstrate that in general there is not a common trend among the three optimization modes presented in this paper since optimizing one parameter may reduce or increase the other two parameters. The only cities that show reduction of PEC while also reducing the CDE are Columbus, MS; Minneapolis, MN; and Miami, FL. For these cities the operational cost always increases when compared to the reference case consisting of using a vapor/compression cycle for cooling and natural gas for heating. On the other hand, for San Francisco and Boston, CCHP systems increase the CDE. In general, if CCHP systems increase the cost of operation, as long as energy savings and reduction of emissions are guaranteed, the implementation of these systems should be considered. [Copyright &y& Elsevier]

Abstract: This study examined how the population shift in the United States between 1960 and 2006 affected the energy demand for heating and cooling. Three analyses were performed. The first analysis was based on climatological considerations only. The second analysis added the energy efficiencies of heating and cooling appliances. The final analysis included the efficiencies of power generating plants as well. All three analyses were based on the 1960 and 2006 population data for the 50 largest metropolitan areas, which currently account for 54% of the total US population. The results indicate that the population shift resulted in about an 11% reduction in the combined energy demand per person for heating and cooling, compared with what the energy demand would have been if the relative population distribution among the metropolitan areas had not changed between 1960 and 2006. [Copyright &y& Elsevier]

The article reports on the origin of Bourbon whiskey in the U.S. As stated, bourbon whiskey is said to be one of America's unique cultural contributions to the world. It is produced at not more that 160 proof from a fermented mash of 51% to 79% corn and stored at not more that 125 proof in charred, new, white oak barrels for at least two years. In addition, its production uses water including the mashing process, cooling the distilled spirit and diluting.

As part of the U.S. Department of Energy's (DOE's) Power Electronics and Electric Machines program area, the DOE's National Renewable Energy Laboratory (NREL) is currently leading a national effort to develop next-generation cooling technologies for hybrid vehicle electronics. Spray cooling has been identified as a potential solution that can dissipate 150-200 W/cm2 while maintaining the chip temperature below 125 ° C. This paper explores the viability and implementation of this cooling scheme. First, commercial coolants are assessed for their suitability to this application in terms of thermal, environmental, and safety concerns and material compatibility. In this assessment, HFE-7100 is identified as the optimum coolant in all performance categories. Next, spray models are used to determine the HFE-7100 spray conditions that meet such stringent heat dissipation requirements. These findings are verified experimentally, demonstrating that spray cooling is a viable thermal management solution for hybrid vehicle electronics. [ABSTRACT FROM AUTHOR]

For most residents in northern temperate zones, the most direct economic impact of global climate change is likely to be changes in home heating and cooling (HC) expenses, estimates of which should be of widespread interest. These residents are increasingly likely to make HC decisions (e.g. switches to electric heat, thermostat settings, conservation investments and behavioral change) in a wider context. The question turns from 'will projected climate change reduce my HC bills?' to 'how will projected climate change, with and without these various actions, affect my HC bills, my total energy use and my greenhouse gas emissions?' We modeled these 3 variables (HC expense, energy use and GHG emissions) on average households in 13 states in the northeastern United States under projected climate change alone, and under projected climate change with 3 modeled choices: increasing use of air-conditioners (AC); switching from petroleum-derived fuels to electric heating; and investing in insulation and efficiency upgrades. High climate change was projected to reduce annual HC expenses for average households in each state, the effect increasing through the century. These savings varied with ratios of heating degree-day to cooling degree-day changes, and with ratios of petroleum-derivative heating to electric heating households; both ratios varied along a north-south gradient in this region. Increasing AC use increased total energy use and CO2 emissions more than it did expenses. Fuel-switching increased the first 2 more than it reduced the third. Upgrades provided the greatest savings in all 3 variables under low and high climate change. Effective energy policies and effective communication with energy users both require require explicit investigation of HC intensities at the household level, and modeling of conservation behaviors as well as purchased upgrades. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates factors explaining the adoption of energy-efficient heating, cooling, window, and lighting technologies in U.S. commercial buildings. It presents multinomial logit models of technology adoption using the 2003 Commercial Buildings Energy Consumption Survey microdata set, examining, first, fundamental building components, and, second, energy-efficient adaptations. Key findings are that the choice of fundamental building components is strongly influenced by locational factors, the activities that are expected to take place in the building, and building-specific characteristics. Lighting technologies are an exception, and are poorly explained by these factors. By contrast, energy-efficient heating, cooling, window, lighting, and control adaptations appear to share common drivers, and are more likely to be adopted in newer, larger, more energy-intensive, owner-occupied buildings. These are the buildings that can best afford the up-front costs of innovation, which is often a design-intensive process. Absent policy interventions, the energy-efficient adaptations are unlikely to diffuse rapidly to the rest of the commercial building stock. [Copyright &y& Elsevier]

Abstract: Developing a divertor concept for fusion power plants to be built after ITER is deemed to be an urgent task to meet the EU Fast Track scenario. This task is particularly challenging because of the wide range of requirements to be met, namely, the high incident peak heat flux, the blanket design with which the divertor has to be integrated, sputtering erosion of the plasma-facing material caused by the incident particles from the plasma, radiation effects on the properties of structural materials, and efficient recovery and conversion of the considerable fraction (∼15%) of the total fusion thermal power incident on the divertor. This paper provides an overview of the development of different conceptual divertor designs (water-cooled, liquid metal-cooled, and helium-cooled types); their advantages and disadvantages and expected performance are outlined and discussed. Emphasis is placed on summarizing the status and progress of R&D associated with He-cooled divertor designs which have been proposed in most of conceptual plant models in Europe and USA. [Copyright &y& Elsevier]