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1.
Nature ; 598(7880): 308-314, 2021 10.
Article in English | MEDLINE | ID: mdl-34646000

ABSTRACT

Estimates of global economic damage caused by carbon dioxide (CO2) emissions can inform climate policy1-3. The social cost of carbon (SCC) quantifies these damages by characterizing how additional CO2 emissions today impact future economic outcomes through altering the climate4-6. Previous estimates have suggested that large, warming-driven increases in energy expenditures could dominate the SCC7,8, but they rely on models9-11 that are spatially coarse and not tightly linked to data2,3,6,7,12,13. Here we show that the release of one ton of CO2 today is projected to reduce total future energy expenditures, with most estimates valued between -US$3 and -US$1, depending on discount rates. Our results are based on an architecture that integrates global data, econometrics and climate science to estimate local damages worldwide. Notably, we project that emerging economies in the tropics will dramatically increase electricity consumption owing to warming, which requires critical infrastructure planning. However, heating reductions in colder countries offset this increase globally. We estimate that 2099 annual global electricity consumption increases by about 4.5 exajoules (7 per cent of current global consumption) per one-degree-Celsius increase in global mean surface temperature (GMST), whereas direct consumption of other fuels declines by about 11.3 exajoules (7 per cent of current global consumption) per one-degree-Celsius increase in GMST. Our finding of net savings contradicts previous research7,8, because global data indicate that many populations will remain too poor for most of the twenty-first century to substantially increase energy consumption in response to warming. Importantly, damage estimates would differ if poorer populations were given greater weight14.


Subject(s)
Carbon Dioxide/economics , Climate Change/economics , Climate Change/statistics & numerical data , Energy-Generating Resources/economics , Energy-Generating Resources/statistics & numerical data , Socioeconomic Factors , Temperature , Air Conditioning/economics , Air Conditioning/statistics & numerical data , Carbon Cycle , Carbon Dioxide/metabolism , Electricity , Heating/economics , Heating/statistics & numerical data , History, 21st Century , Human Activities , Poverty/economics , Poverty/statistics & numerical data , Social Sciences
2.
PLoS One ; 15(12): e0240461, 2020.
Article in English | MEDLINE | ID: mdl-33259504

ABSTRACT

Commercial buildings account for one third of the total electricity consumption in the United States and a significant amount of this energy is wasted. Therefore, there is a need for "virtual" energy audits, to identify energy inefficiencies and their associated savings opportunities using methods that can be non-intrusive and automated for application to large populations of buildings. Here we demonstrate virtual energy audits applied to large populations of buildings' time-series smart-meter data using a systematic approach and a fully automated Building Energy Analytics (BEA) Pipeline that unifies, cleans, stores and analyzes building energy datasets in a non-relational data warehouse for efficient insights and results. This BEA pipeline is based on a custom compute job scheduler for a high performance computing cluster to enable parallel processing of Slurm jobs. Within the analytics pipeline, we introduced a data qualification tool that enhances data quality by fixing common errors, while also detecting abnormalities in a building's daily operation using hierarchical clustering. We analyze the HVAC scheduling of a population of 816 buildings, using this analytics pipeline, as part of a cross-sectional study. With our approach, this sample of 816 buildings is improved in data quality and is efficiently analyzed in 34 minutes, which is 85 times faster than the time taken by a sequential processing. The analytical results for the HVAC operational hours of these buildings show that among 10 building use types, food sales buildings with 17.75 hours of daily HVAC cooling operation are decent targets for HVAC savings. Overall, this analytics pipeline enables the identification of statistically significant results from population based studies of large numbers of building energy time-series datasets with robust results. These types of BEA studies can explore numerous factors impacting building energy efficiency and virtual building energy audits. This approach enables a new generation of data-driven buildings energy analysis at scale.


Subject(s)
Commerce/economics , Data Warehousing , Electricity , Housing/economics , Air Conditioning/economics , Air Conditioning/statistics & numerical data , Cluster Analysis , Commerce/statistics & numerical data , Datasets as Topic , Heating/economics , Heating/statistics & numerical data , Housing/statistics & numerical data , United States
3.
Article in English | MEDLINE | ID: mdl-32784593

ABSTRACT

The objective of the study was to investigate, using academic-community epidemiologic co-analysis, the odds of reported heat-related illness for people with (1) central air conditioning (AC) or window unit AC versus no AC, and (2) fair/poor vs. good/excellent reported health. From 2016 to 2017, 101 Detroit residents were surveyed once regarding extreme heat, housing and neighborhood features, and heat-related illness in the prior 5 years. Academic partners selected initial confounders and, after instruction on directed acyclic graphs, community partners proposed alternate directed acyclic graphs with additional confounders. Heat-related illness was regressed on AC type or health and co-selected confounders. The study found that heat-related illness was associated with no-AC (n = 96, odds ratio (OR) = 4.66, 95% confidence interval (CI) = 1.22, 17.72); living ≤5 years in present home (n = 57, OR = 10.39, 95% CI = 1.13, 95.88); and fair/poor vs. good/excellent health (n = 97, OR = 3.15, 95% CI = 1.33, 7.48). Co-analysis suggested multiple built-environment confounders. We conclude that Detroit residents with poorer health and no AC are at greater risk during extreme heat. Academic-community co-analysis using directed acyclic graphs enhances research on community-specific social and health vulnerabilities by identifying key confounders and future research directions for rigorous and impactful research.


Subject(s)
Air Conditioning/statistics & numerical data , Extreme Heat/adverse effects , Heat Stress Disorders/epidemiology , Adolescent , Adult , Aged , Community-Based Participatory Research , Female , Health Status , Hot Temperature , Humans , Male , Michigan/epidemiology , Middle Aged , Quality of Life , Surveys and Questionnaires
6.
J Prev Med Public Health ; 53(1): 15-25, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32023670

ABSTRACT

OBJECTIVES: The purpose of this study was to investigate the health effects of air conditioning use during the 2018 heat wave in Korea, included the highest temperature ever recorded in the nation. METHODS: The participants in this study were 1000 adults aged 19 years and older recruited from across Korea. The participants were asked about their experience of symptoms of various diseases, disruptions of their daily lives, and use of air conditioning during the heat wave. The associations between air conditioning use during the heat wave and health outcomes were analyzed using the chi-square test and multiple logistic regression models. RESULTS: Among participants who lacked air conditioning in the main space where they spent time outside the home, 33.9%, 8.1%, 43.5%, and 19.4% experienced symptoms of heat-related, cardiovascular, nervous system diseases, and air-conditioningitis, respectively. In comparison, participants who did have air conditioning outside the home experienced the same symptoms at proportions of 21.0%, 1.9%, 26.8%, and 34.2%, respectively (p=0.027, 0.007, 0.007, and 0.023, respectively). Among participants who had no air conditioner at home, 10.0% were absent from school or work due to the heat wave. In contrast, among participants who had an air conditioner at home, only 3.7% were absent as a result of the heat wave (p=0.007). CONCLUSIONS: When air conditioning was not used at home or in the main space where participants spent time outside the home during the 2018 heat wave, adverse health effects were more prevalent, but the risk of air-conditioningitis was reduced.


Subject(s)
Air Conditioning/statistics & numerical data , Cardiovascular Diseases/epidemiology , Hot Temperature/adverse effects , Nervous System Diseases/epidemiology , Adult , Chronic Disease/epidemiology , Female , Humans , Male , Middle Aged , Republic of Korea/epidemiology , Self Report , Surveys and Questionnaires , Young Adult
7.
Rev. esp. quimioter ; 33(1): 11-17, feb. 2020. tab
Article in English | IBECS | ID: ibc-196177

ABSTRACT

OBJECTIVE: This study evaluated the compliance with preventive measures against malaria of the personnel treated in the Spanish Defence International Vaccination Centre (CVI). MATERIAL AND METHODS: A retrospective study was conducted from November to December 2017. The population was 534 individuals. All were treated in CVI, prior to their deployment on endemic areas of malaria, with prevention measures type C and D. A questionnaire of 23 items was elaborated. RESULTS: The percentage of response to the questionnaire was 36.9% (n=194), 100% were male. Air conditioner was the most used protection measure 93.8% (IC 95% 90.4-97.2). Only 35.5% (95% CI: 28.8-42.2) of them, showed good adherence to medication. The factors that influenced in the adherence were the country and the length of deployment. It was not established a direct relationship between the occurrence of adverse reactions and low adherence to treatment. CONCLUSIONS: The general protection measures against malaria were met in a high percentage, whilst the use of chemoprophylaxis was very low. These epidemiological data allowed us to know the validity of the health education that is provided in the traveller's care consultation. It also allowed being aware of the possibilities of infection and import of malaria by personnel of the Spanish Armed Forces. The traveller's office will reinforce the importance of taking the adequate chemoprophylaxis trough conferences and informative diptychs


OBJETIVO: Este estudio evaluó el cumplimiento de las medidas preventivas contra la malaria por parte del personal tratado en el Centro de Vacunación Internacional de la Defensa. MATERIAL Y MÉTODOS: Se realizó un estudio retrospectivo de noviembre a diciembre de 2017. La población era de 534 individuos. Todos fueron tratados en el Centro de Vacunación Internacional, antes de su despliegue en áreas endémicas de malaria, en las que según indicación de la Organización Mundial de la Salud se recomendaba el uso de medidas de prevención tipo C y D. Se elaboró un cuestionario de 23 ítems. RESULTADOS: El porcentaje de respuesta al cuestionario fue del 36,9% (n = 194), el 100% eran hombres. El aire acondicionado fue la medida de protección más utilizada 93,8% (IC 95% 90,4-97,2). Solo el 35,5% (IC 95%: 28,8-42,2) de ellos, mostraron buena adherencia a la medicación. Los factores que influyeron en la adhesión fueron el país y la duración del despliegue. No se estableció una relación directa entre la aparición de reacciones adversas y la baja adherencia al tratamiento. CONCLUSIONES: Las medidas generales de protección contra la malaria se cumplieron en un porcentaje elevado, mientras que el uso de quimioprofilaxis fue bajo. Estos datos epidemiológicos nos permitieron conocer la validez de la educación sanitaria que se brinda en la consulta de atención al viajero. También permitió conocer las posibilidades de infección e importación de malaria por parte del personal de las Fuerzas Armadas Españolas. La oficina del viajero reforzará la importancia de una quimioprofilaxis adecuada a través de conferencias y dípticos informativos


Subject(s)
Humans , Male , Female , Malaria/prevention & control , Medication Adherence/statistics & numerical data , Military Personnel , Air Conditioning/statistics & numerical data , Antimalarials/therapeutic use , Educational Status , Health Surveys/statistics & numerical data , Insect Repellents/administration & dosage , Mosquito Nets/statistics & numerical data , Retrospective Studies , Spain
8.
Rev Esp Quimioter ; 33(1): 11-17, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31965778

ABSTRACT

OBJECTIVE: This study evaluated the compliance with preventive measures against malaria of the personnel treated in the Spanish Defence International Vaccination Centre (CVI). METHODS: A retrospective study was conducted from November to December 2017. The population was 534 individuals. All were treated in CVI, prior to their deployment on endemic areas of malaria, with prevention measures type C and D. A questionnaire of 23 items was elaborated. RESULTS: The percentage of response to the questionnaire was 36.9% (n=194), 100% were male. Air conditioner was the most used protection measure 93.8% (IC 95% 90.4-97.2). Only 35.5% (95% CI: 28.8-42.2) of them, showed good adherence to medication. The factors that influenced in the adherence were the country and the length of deployment. It was not established a direct relationship between the occurrence of adverse reactions and low adherence to treatment. CONCLUSIONS: The general protection measures against malaria were met in a high percentage, whilst the use of chemoprophylaxis was very low. These epidemiological data allowed us to know the validity of the health education that is provided in the traveller's care consultation. It also allowed being aware of the possibilities of infection and import of malaria by personnel of the Spanish Armed Forces. The traveller's office will reinforce the importance of taking the adequate chemo-prophylaxis trough conferences and informative diptychs..


Subject(s)
Malaria/prevention & control , Medication Adherence/statistics & numerical data , Military Deployment , Military Personnel , Travel-Related Illness , Air Conditioning/statistics & numerical data , Antimalarials/therapeutic use , Educational Status , Female , Health Surveys/statistics & numerical data , Humans , Insect Repellents/administration & dosage , Male , Mosquito Nets/statistics & numerical data , Retrospective Studies , Spain
9.
Br J Math Stat Psychol ; 73(3): 474-505, 2020 11.
Article in English | MEDLINE | ID: mdl-31912906

ABSTRACT

We propose a latent topic model with a Markov transition for process data, which consists of time-stamped events recorded in a log file. Such data are becoming more widely available in computer-based educational assessment with complex problem-solving items. The proposed model can be viewed as an extension of the hierarchical Bayesian topic model with a hidden Markov structure to accommodate the underlying evolution of an examinee's latent state. Using topic transition probabilities along with response times enables us to capture examinees' learning trajectories, making clustering/classification more efficient. A forward-backward variational expectation-maximization (FB-VEM) algorithm is developed to tackle the challenging computational problem. Useful theoretical properties are established under certain asymptotic regimes. The proposed method is applied to a complex problem-solving item in the 2012 version of the Programme for International Student Assessment (PISA).


Subject(s)
Markov Chains , Models, Statistical , Air Conditioning/statistics & numerical data , Algorithms , Bayes Theorem , Cluster Analysis , Computer Simulation , Educational Measurement/statistics & numerical data , Humans , Likelihood Functions , Numerical Analysis, Computer-Assisted , Problem Solving
10.
Environ Sci Pollut Res Int ; 27(7): 7341-7352, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31884553

ABSTRACT

Employee green behavior is an environmentally friendly behavior in the workplace and is an important basis for transforming an organization's macrolevel sustainable development strategy into concrete practice. How does employees' pro-environmental attitude affect the implementation of their behaviors? To answer this question, we examined the relationship between pro-environmental attitude and employee green behavior and the roles of motivational states and green work climate perceptions in this process. The results showed that pro-environmental attitude positively predicted required employee green behavior and voluntary employee green behavior and that these relationships were mediated by controlled and autonomous motivations. In addition, this study showed that the positive role of pro-environmental attitude in controlled motivation and autonomous motivation was moderated by green work climate perceptions. Finally, we discuss the theoretical and practical implications.


Subject(s)
Motivation , Organizational Culture , Air Conditioning/statistics & numerical data , Attitude , Workplace
11.
J Perianesth Nurs ; 35(2): 178-184, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31859207

ABSTRACT

PURPOSE: Compare perioperative temperature management between forced-air warming (FAW) and resistive-polymer heating blankets (RHBs). DESIGN: A retrospective, quasi-experimental study. METHODS: Retrospective data analysis of nonspine orthopedic cases (N = 426) over a one-year period including FAW (n = 119) and RHBs (n = 307). FINDINGS: FAW was associated with a significantly higher final intraoperative temperature (P = .001, d = 0.46) than the RHB. The incidence of hypothermia was not found to be significantly different at the end (P = .102) or anytime throughout surgery (P = .270). Of all patients who started hypothermic, the FAW group had a lower incidence of hypothermia at the end of surgery (P = .023). CONCLUSIONS: FAW was associated with higher final temperatures and a greater number of normothermic patients than RHBs. However, no causal relationship between a warming device and hypothermia incidence should be assumed.


Subject(s)
Air Conditioning/instrumentation , Heating/instrumentation , Hypothermia/prevention & control , Adult , Aged , Aged, 80 and over , Air Conditioning/methods , Air Conditioning/statistics & numerical data , Body Temperature Regulation/physiology , Female , Heating/standards , Heating/statistics & numerical data , Humans , Hypothermia/therapy , Intraoperative Complications/prevention & control , Male , Middle Aged , Perioperative Period , Polymers/administration & dosage , Polymers/therapeutic use , Retrospective Studies , Statistics, Nonparametric
13.
J Healthc Eng ; 2019: 6939632, 2019.
Article in English | MEDLINE | ID: mdl-31098009

ABSTRACT

A person stays indoors for about 85%∼90% time of his lifetime, and the need for a comfortable indoor environment is getting higher; thus, the air-conditioning dependency becomes intense too. Nowadays, residents focus on both the comfortable living environment and indoor air quality. A closed environment will become hazardous because of carbon dioxide released during respiration and toxic organic solvent vapor released from interior decoration. In order to improve the indoor air quality (IAQ), we must allow outer fresh air into the indoor space and release the dirty air out. But while taking in fresh air, the heat and factory/vehicle exhaust are also introduced. Indoor CO2, HCHO, and VOCs and outer dirty gas threaten human health badly. To solve this problem, we bring up an innovative low-power-consuming full-outer-air-intake natural air-conditioning system that completely separates intake and exhaust air, which is a solution for cross-contamination and makes mass/energy exchange by means of air and water. Design airflow exceeds 300∼500 CFM, steam evaporation mass rate reaches 3.13∼3.88 kg/hr, and heat exchange capacity becomes 1,855∼2,300 kcal/hr. The sensible heat effectiveness is 71%∼112%, and EER exceeds 14.05∼17.42 kcal/W·h. In addition, the system under design can be of positive or negative pressure status according to the user's or work's requirement. It creates a comfortable and healthy living environment by supplying clean and fresh outer ambient air with low power consumption.


Subject(s)
Air Conditioning/instrumentation , Air Conditioning/methods , Air Conditioning/statistics & numerical data , Air Pollutants/analysis , Air Pollution, Indoor/analysis , Carbon Dioxide/analysis , Construction Industry , Electric Power Supplies/statistics & numerical data , Engineering , Environmental Monitoring , Equipment Design , Humans , Models, Theoretical
14.
Inj Prev ; 25(6): 581-584, 2019 12.
Article in English | MEDLINE | ID: mdl-30948441

ABSTRACT

We explore whether the timing and burden of paediatric window fall injuries in the Seattle area have changed with higher temperatures and increased air conditioning (AC) prevalence. Using hospital trauma registry records from 2005 to 2017, along with population estimates from the National Center for Health Statistics, we calculate trauma incidence rates from paediatric window falls. Using local temperature data, we explore the relationship between temperature increases over time and the seasonality and rate of incidents. Window falls are a substantial cause of injury among children, with an annual trauma incidence rate among children age 0-8 of 10.4 per 100 000 boys and 5.9 per 100 000 girls in our sample. We find a mildly positive trend in the crude rate of window falls over the study period, increasing further when a population-level adjustment for AC prevalence is included. We do not find evidence of earlier injury timing during the calendar year.


Subject(s)
Accidental Falls/mortality , Suburban Population/statistics & numerical data , Urban Population/statistics & numerical data , Wounds and Injuries/mortality , Adolescent , Air Conditioning/statistics & numerical data , Child , Child, Preschool , Female , Health Surveys , Hot Temperature , Housing/standards , Humans , Incidence , Infant , Infant, Newborn , Male , Registries , Seasons , Severity of Illness Index , Washington/epidemiology
15.
Article in English | MEDLINE | ID: mdl-30813565

ABSTRACT

High-throughput quantitative PCR combined with Illumina sequencing and network analysis were used to characterize the antibiotic resistance gene (ARG) profiles in air-conditioning filters from different environments. In total, 177 ARGs comprising 10 ARG types were determined. The detectable numbers and the relative abundance of ARGs in hospitals and farms were significantly higher than those in city and village residences. Compared to hospitals, farms had a higher level of tetracycline, multidrug, integrase, and macrolide⁻lincosamide⁻streptogramin (MLS) B resistance genes but a lower level of beta-lactam resistance genes. The bl3_cpha gene was the most abundant resistance gene subtype in hospital samples with an abundance of 2.01 × 10-4 copies/16S rRNA, while a level of only 5.08 × 10-12 copies/16S rRNA was observed in farm samples. There was no significant difference in bacterial diversity among the hospitals, farms, and residences, and Proteobacteria was the most abundant phylum. Network analysis revealed that Proteobacteria and Actinobacteria were possible hosts of the beta-lactam, MLSB, aminoglycoside, multidrug, sulfonamide, and tetracycline resistance genes. The results demonstrate that ARGs exist in indoor environments and that farms and hospitals are important sources. This study provides a useful reference for understanding the distribution patterns and risk management of ARGs in indoor environments.


Subject(s)
Air Conditioning/statistics & numerical data , Bacteria/genetics , Drug Resistance, Bacterial/genetics , Environmental Microbiology , Environmental Monitoring , Genes, Bacterial/genetics , Air Filters/microbiology , Anti-Bacterial Agents/pharmacology , Bacteria/classification , Bacteria/drug effects , Farms/statistics & numerical data , Hospitals/statistics & numerical data , Housing/statistics & numerical data , Prevalence
16.
Ann Otol Rhinol Laryngol ; 128(7): 601-607, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30818962

ABSTRACT

OBJECTIVES: Empty nose syndrome (ENS) is thought to have multiple etiologies, one of which is a postsurgical phenomenon resulting from excessive loss of nasal tissues, particularly the inferior turbinate. Given that the inferior turbinate is instrumental in maintaining nasal homeostasis in different environments, it is believed that ENS symptoms arise only in more arid regions of the world. The aim of this study was to recruit an international population of individuals with ENS to investigate the association of local climate factors on the incidence and severity of ENS-specific symptoms. METHODS: A cross-sectional study was performed of individuals from an international ENS database. ENS status was determined on the basis of a positive ENS questionnaire score (Empty Nose Syndrome 6-Item Questionnaire) and sinus computed tomographic imaging with supporting medical documentation. Participants completed a survey encompassing demographic, geographic, and symptom indicators. Climate variables were collected from global climate databases. Participant location was classified according to the Köppen-Geiger climate system. Pearson correlation analysis was performed using α = 0.05 to determine significance. RESULTS: Fifty-three individuals with ENS were included. Participants were distributed across 5 continents and 15 countries (representing 4 distinct Köppen-Geiger zones). Although local climate factors varied significantly within this cohort, no significant association was found between Empty Nose Syndrome 6-Item Questionnaire symptom severity and these climate factors. However, most study participants reported exacerbation of their ENS symptoms in response to dry air (94%), air conditioning (64%), changes in season and weather (60%), and transitioning between indoors and outdoors (40%). This suggests that everyday local environmental factors may influence the well-being of these patients more than global, climate-level shifts. CONCLUSIONS: ENS symptom severity does not appear to be related to climate or geographic factors. These findings deviate from the traditional dogma that ENS is experienced only in arid regions (or precluded in humid regions) and highlight the importance of recognizing this condition independent of geographic location.


Subject(s)
Environmental Exposure/statistics & numerical data , Nasal Obstruction/surgery , Nose Diseases/epidemiology , Postoperative Complications/epidemiology , Turbinates/pathology , Adult , Air Conditioning/statistics & numerical data , Atrophy/epidemiology , Climate , Cross-Sectional Studies , Female , Humans , Humidity , Male , Middle Aged , Nasal Surgical Procedures/adverse effects , Nose Diseases/etiology , Postoperative Complications/etiology , Seasons , Severity of Illness Index , Surveys and Questionnaires , Syndrome , Turbinates/surgery , Weather , Young Adult
17.
Epidemiology ; 29(6): 756-764, 2018 11.
Article in English | MEDLINE | ID: mdl-30113342

ABSTRACT

BACKGROUND: With climate change, temperatures are increasing. Heat-associated health events disproportionately affect certain subpopulations. However, prior research has often lacked information on individual-level health and air conditioning and neighborhood stressors/protections. OBJECTIVES: To assess whether (1) heat (2-day mean temperature above local 75th percentiles) is associated with increased heart rate and decreased blood pressure, controlling for age, time, season, daily ozone, and daily particulate matter (PM2.5) and (2) associations differ by antihypertensive medication use, renal function, fasting glucose, emotional support, air conditioning ownership and use, normalized difference vegetation index, neighborhood safety, and residence- specific oxides of nitrogen and PM2.5. METHODS: Health and behavioral characteristics were obtained repeatedly on participants of the Multi-Ethnic Study of Atherosclerosis in six US sites (2000-2010). These were linked with airport temperature, air quality, and satellite- and survey-derived neighborhood characteristics. We used a fixed-effects design, regressing health outcomes on linear temperature splines with knots at the 75th percentiles, interaction terms for each characteristic, and adjustment for month of year, age, PM2.5, and ozone. RESULTS: Overall, heat was not associated with heart rate. However, for a 2°C increase in heat, systolic blood pressure decreased by 1.1 mmHg (95% CI = -1.6, -0.6) and diastolic blood pressure by 0.3 mmHg (95% CI = -0.6, -0.1). Among nonusers of antihypertensive medications, heat-associated decreases in SBP were 2.1 mmHg greater among individuals with central air conditioning versus those without. Confidence intervals around the remaining modifiers were wide after multiple-comparisons corrections or sensitivity analyses. CONCLUSIONS: Outdoor heat is associated with decreasing blood pressure, and cardiovascular vulnerability may vary primarily by ownership of central air conditioning.


Subject(s)
Atherosclerosis/etiology , Blood Pressure , Heart Rate , Hot Temperature/adverse effects , Aged , Aged, 80 and over , Air Conditioning/statistics & numerical data , Baltimore/epidemiology , Chicago/epidemiology , Cities/epidemiology , Ethnicity , Female , Humans , Los Angeles/epidemiology , Male , Middle Aged , New York City/epidemiology , Risk Factors , United States/epidemiology
18.
Environ Monit Assess ; 190(5): 276, 2018 Apr 12.
Article in English | MEDLINE | ID: mdl-29651634

ABSTRACT

In this study, passenger comfort and the air pollution status of the micro-environmental conditions in an air-conditioned bus were investigated through questionnaires, field measurements, and a numerical simulation. As a subjective analysis, passengers' perceptions of indoor environmental quality and comfort levels were determined from questionnaires. As an objective analysis, a numerical simulation was conducted using a discrete phase model to determine the diffusion and distribution of pollutants, including particulate matter with a diameter < 10 µm (PM10), which were verified by experimental results. The results revealed poor air quality and dissatisfactory thermal comfort conditions in Jinan's air-conditioned bus system. To solve these problems, three scenarios (schemes A, B, C) were designed to alter the ventilation parameters. According to the results of an improved simulation of these scenarios, reducing or adding air outputs would shorten the time taken to reach steady-state conditions and weaken the airflow or lower the temperature in the cabin. The airflow pathway was closely related to the layout of the air conditioning. Scheme B lowered the temperature by 0.4 K and reduced the airflow by 0.01 m/s, while scheme C reduced the volume concentration of PM10 to 150 µg/m3. Changing the air supply angle could further improve the airflow and reduce the concentration of PM10. With regard to the perception of airflow and thermal comfort, the scheme with an airflow provided by a 60° nozzle was considered better, and the concentration of PM10 was reduced to 130 µg/m3.


Subject(s)
Air Conditioning/statistics & numerical data , Air Pollution, Indoor/analysis , Air Pollution/statistics & numerical data , Motor Vehicles/statistics & numerical data , Air Pollutants/analysis , Air Pollution/analysis , Air Pollution, Indoor/statistics & numerical data , Environmental Monitoring , Humans , Particulate Matter/analysis , Temperature , Ventilation
19.
Article in English | MEDLINE | ID: mdl-29149078

ABSTRACT

It is well known that personal cooling improves thermal comfort and save energy. This study aims to: (1) compare different personal cooling systems and (2) understand what influences users' willingness to adopt them. A series of experiments on several types of personal cooling systems, which included physical measurements, questionnaires and feedback, was conducted in a real office environment. The obtained results showed that personal cooling improved comfort of participants in warm environments. Then an improved index was proposed and used to compare different types of personal cooling systems in terms of comfort and energy efficiency simultaneously. According to the improved index, desk fans were highly energy-efficient, while the hybrid personal cooling (the combination of radiant cooling desk and desk fan) consumed more energy but showed advantages of extending the comfortable temperature range. Moreover, if personal cooling was free, most participants were willing to adopt it and the effectiveness was the main factor influencing their willingness, whereas if participants had to pay, they probably refused to adopt it due to the cost and the availability of conventional air conditioners. Thus, providing effective and free personal cooling systems should be regarded as a better way for its wider application.


Subject(s)
Air Conditioning/statistics & numerical data , Air Conditioning/standards , Efficiency , Household Articles/statistics & numerical data , Household Articles/standards , Research Design/standards , Workplace/standards , Adult , Female , Humans , Male , Middle Aged , Research Design/statistics & numerical data , Surveys and Questionnaires
20.
PLoS One ; 12(11): e0188033, 2017.
Article in English | MEDLINE | ID: mdl-29155862

ABSTRACT

Projecting the long-term trends in energy demand is an increasingly complex endeavor due to the uncertain emerging changes in factors such as climate and policy. The existing energy-economy paradigms used to characterize the long-term trends in the energy sector do not adequately account for climate variability and change. In this paper, we propose a multi-paradigm framework for estimating the climate sensitivity of end-use energy demand that can easily be integrated with the existing energy-economy models. To illustrate the applicability of our proposed framework, we used the energy demand and climate data in the state of Indiana to train a Bayesian predictive model. We then leveraged the end-use demand trends as well as downscaled future climate scenarios to generate probabilistic estimates of the future end-use demand for space cooling, space heating and water heating, at the individual household and building level, in the residential and commercial sectors. Our results indicated that the residential load is much more sensitive to climate variability and change than the commercial load. Moreover, since the largest fraction of the residential energy demand in Indiana is attributed to heating, future warming scenarios could lead to reduced end-use demand due to lower space heating and water heating needs. In the commercial sector, the overall energy demand is expected to increase under the future warming scenarios. This is because the increased cooling load during hotter summer months will likely outpace the reduced heating load during the more temperate winter months.


Subject(s)
Air Conditioning/statistics & numerical data , Climate Change/economics , Energy-Generating Resources/economics , Heating/statistics & numerical data , Models, Statistical , Renewable Energy/economics , Air Conditioning/economics , Computer Simulation , Conservation of Energy Resources/trends , Heating/economics , Humans , Indiana , Seasons
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