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air quality improvement in Los Angeles Perspectives for developing cities

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Frontiers of Environmental Science & Engineering 2016年第5期10卷 69-81页

作者： David D. Parrish Jin Xu Bart Croes Min Shao Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder CO 80305 USA NOAA Earth System Research Laboratory 325 Broadway R/CSD7 Boulder CO 80305 USA california air resources board 1001 1 Street P.O. Box 2815 Sacramento CA 95814 USA College of Environmental Sciences and Engineering Peking University Beijing 100871 China

air quality improvement in Los Angeles, california is reviewed with an emphasis on aspects that may inform air quality policy formulation in developing cities. In the mid-twentieth century the air quality in Los Angeles was degraded to an extent comparable to the worst found in developing cities today; ozone exceeded 600 ppb and annual average particulate matter 〈 10 μm reached -150 μg.m -3. Today＇s air quality is much better due to very effective emission controls; e.g., modem automobilcs emit about 1% of the hydrocarbons and carbon monoxide emitted by vehicles of 50 years ago. An overview is given of the emission control efforts in Los Angeles and their impact on anabient concentrations of primary and secondary pollutants： the costs and health benefits of these controls arc briefly summarized, Today＇s developing cities have new challenges that are discussed： the effects of regional pollution transport are much greater in countries with very high population densities： often very large current populations must be supplied with goods and services even while economic development and air quality concerns are addressed; and many of currently developing cities arc located in or close to the tropics where photochemical processing of pollution is expected to be more rapid than at higher latitudes. The air quality issues of Beijing are briefly compared and contrasted with those of Los Angeles, and the opportunities for co-benefits for climate and air quality improvement are pointed out.

关键词： air pollution Ozone Particulate matter Control technology

Source apportionment of atmospheric particulate carbon in Las Vegas,Nevada,USA

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Particuology 2013年第1期11卷 110-118页

作者： Mark C.Green Judith C.Chow M.-C.Oliver Chang L.-W.Antony Chen Hampden D.Kuhns Vicken R.Etyemezian John G.Watson Division of Atmospheric Sciences Desert Research Institute2215 Raggio ParkwayRenoNV 89512USA Division of Atmospheric Sciences Desert Research Institute.2215 Raggio ParkwayRenoNV 89512USA State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina california air resources board 9528 Telstar Ave.El MonteCA 91731USA

A study was conducted to quantify wintertime contributions of source types to carbonaceous PM2.5 at four urban sites in the Las Vegas Valley, one of the most rapidly growing urban areas in the southwestern United States. Twenty-four hour average ambient samples were collected for mass, ions, elements, organic carbon （OC）, elemental carbon （EC）, and trace organic markers analysis. Additional measurements were made to determine diurnal patterns in light-absorbing black carbon （BC） as a marker for combustion sources. Carbonaceous PM sources of on-road gasoline vehicles, on-road diesel vehicles, and off-road diesel engines were characterized with their chemical profiles, as well as fuel-based emission factors, using an In-Plume Sampling System. The Effective Variance Chemical Mass Balance （EV-CMB） source apportionment model was applied to the ambient samples collected, using source profiles developed in this study as well as profiles from other relevant studies. Four main sources contributed to PM2.5 carbon within the Las Vegas Valley：（1） paved road dust, （2） on-road gasoline vehicles, （3） residential wood combustion, and （4） on-road diesel vehicles. CMB estimated that on-road mixed fleet gasoline vehicles are the largest source for OC and EC at all the sites. The contribution of paved road dust to both OC and EC was 5-10% at the four sites. On-road diesel vehicles contribute 22% of the OC and 34% of the EC at a site near the city center, which is located immediately downwind of a major freeway. Residential wood combustion is a more important source than on-road diesel vehicles for two residential neighborhood sites, These results are consistent with our conceptual model, and the research methodology may be applied to studying other urban areas.

关键词： Source characterization Mobile sources Elemental carbon Source apportionment Organic marker

Influence of High Relative Humidity on Secondary Organic Carbon: Observations at a Background Site in East China

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Journal of Meteorological Research 2019年第5期33卷 905-913页

作者： Linlin LIANG Guenter ENGLING Yuan CHENG Xiaoye ZHANG Junying SUN Wanyun XU Chang LIU Gen ZHANG Hui XU Xuyan LIU Qianli MA State Key Laboratory of Severe Weather&Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China State Environmental Protection Key Laboratory of Sources and Control of air Pollution Complex Beijing 100084China Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512USA california air resources board CA 91731USA School of Environment Harbin Institute of TechnologyHarbin 150001China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China Lin'an Regional Atmosphere Background Station Lin'an 311307China

To investigate the impacts of relative humidity(RH) on secondary organic aerosol(SOA) concentrations and chemical reactions, the carbonaceous aerosol components [i.e., organic carbon(OC) and element carbon(EC)] were quantified in daily PM2.5 samples collected at a background site in East China during summer 2015. Based on the method of EC-tracer, the concentration of secondary organic carbon(SOC) demonstrated an obvious negative relationship with RH higher than 60%. Moreover, the ratio of SOC/EC also exhibited obvious decreasing trends with increasing RH, indicating negative effects for chemical production of SOA under high RH conditions. Due to high RH,photochemistry was weakened, gaseous oxidant concentrations was lowered(e.g., significantly decreased O3 levels),and the production rates of SOA were relatively low. On the other hand, because of more water uptake under higher RH conditions, the aerosol droplet acidity was reduced and enhancement of SOA formation by acidity was accordingly absent. In addition, high RH also plays an important role in changing viscosity of pre-existing aerosol coatings,which can affect reactive uptake yield of SOA. Overall, the results from this study imply that SOA production may be more associated with photochemical processes, while aqueous-phase chemistry is not very important for some SOA formation in a moist ambient environment. In the ambient atmosphere, oxidant concentrations, reaction rates,airborne species, etc., are highly variable. How do these factors affect SOA yields under given ambient environment warrants further detailed investigations.

关键词： relative humidity organic aerosol secondary organic carbon(SOC) photochemistry aqueous-phase

The Great Cholesterol Quandary and Global Consciousness Awakening

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World Journal of Cardiovascular Diseases 2023年第11期13卷 718-755页

作者： Abdullah Alabdulgader Scientific board HeartMath Institute California USA

Ancestors of human species have been living on the planet earth for about six million years while the modern form of humans only evolved about 200,000 years ago. Civilization is only about 6000 years old, and industrialization started in the 1800s. World population interconnectedness is enhanced with love and mercy but disrupted with dishonest, lies and wars. Human species has been feeding on animal fat as the finest and prime source of energy for all human history. In 1953 Ancel Keys and collaborates illusionized human kind that their historical source of energy is toxic. Massive health, behavioral as well as economic consequences followed. Human hearts known historically to be the seat of spirit, soul and emotions is proven by our group to orchestrate with global energetic fields. Global consciousness as represented by the planetary electromagnetic fields is in critical need to be feed with awakening merciful information. Documents refuting Ancek Keys dogma and reverting humanity to the truth in their energy source is presented in this review. The harmony we expect is not only physiological but will affect our global planetary environment for the wellbeing of human species in earth.

关键词： Atherosclerosis Cholesterol Statin Nobel Laureates Hypocholesterolemia Global Consciousness

A model supported by GIS for locating and quantifying PM_(2.5) emission originated from residential wood burning

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Journal of Environmental Sciences 2005年第5期17卷 861-865页

作者： ZHOU De-min RADKE John TIAN Yong-qian XU Jian-chun MU Lan Northeast Institute of Geography and Agricultural Ecology Chinese Academy Sciences Changchun 130012 China Geographical Information Science Center 102 Wheeler Hall University of California Berkeley CA 94720 USA Center for Assessment and Monitoring of Forest and Environmental resources 151 Hilgard Hall University of California Berkeley CA 94720 USA

A research method was presented for spatially quantifying and allocating the potential activity of a fine particle matter emission （ PM2.5 ）, which originated from residential wood burning （RWB） in this study. Demographic, hypsographic, climatic and topographic data were compiled and processed within a geographic information system（GIS）, and as independent variables put into a linear regression model for describing spatial distribution of the potential activity of residential wood burning as primary heating source. In order to improve the estimation, the classifications of urban, suburban and rural were redefined to meet the specifications of this application. Also, several definitions of forest accessibility were tested for estimation. The results suggested that the potential activity of RWB was mostly determined by elevation of a location, forest accessibility, urban/non-urban position, climatic conditions and several demographic variables. The linear regression model could explain approximately 86% of the variation of surveyed potential activity of RWB. The analysis results were validated by employing survey data collected mainly from a WebGIS based phone interview over the study area in central california. Based on lots free public GIS data, the model provided an easy and ideal tool for geographic researchers, environmental planners and administrators to understand where and how much PM2.5 emission from RWB was contributed to air quality. With this knowledge they could identify regions of concern, and better plan mitigation strategies to improve air quality. Furthermore, it allows for future adjustment on some parameters as the spatial analysis method is implemented in the different regions or various eco-social models.

关键词： residential wood burning(RWB) PM2.5 demographical characteristies Geographic information system(GIS) stepwise linear regression

Feasibility of telemedicine program using a hand-held nonmydriatic retinal camera in Panama

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International Journal of Ophthalmology(English edition) 2022年第6期15卷 962-966页

作者： Alexander SHimstead Janani Prasad Sean Melucci Kevin MGustafson Paul EIsraelsen Andrew Browne School of Medicine University of CaliforniaIrvineCalifornia 92697USA Gavin Herbert Eye Institute Department of OphthalmologyUniversity of CaliforniaIrvineCalifornia 92697USA

AIM: To evaluate the image quality of a telemedicine screening program for retinal disease using a nonmydriatic camera among rural island communities in Bocas del Toro, ***: In June 2018, a group of three medical students volunteered at clinics operated by the Floating Doctors in the province of Bocas del Toro, Panama. Nonmydriatic images of the retina were obtained using the Pictor Plus(Volk Optical, Mentor OH), randomized, and sent to two board-certified ophthalmologists at the University of california, Irvine for analysis using a modified version of the FOTO-ED scale. Inter-rater reliability was calculated using the kappa ***: Seventy patients provided a total of 127 images. Average image quality was 3.31, and most frequent image quality was 4/5 on the FOTO-ED scale. Thirty patients had at least one eye image with ideal quality(42.86%), while only one patient had no adequate photos taken(1.43%). However, high quality images were obtained in both eyes in only 12 patients(17.14%). The inter-rater reliability between the two ophthalmologists was ***: Further improvements are necessary to acquire higher quality images more reliably. This may include further training and experience or mydriasis.

关键词： telemedicine retina nonmydriatic camera fundus screening feasibility low-resource setting

含有加州杏仁粉和烘焙酶制剂的面团体系的流变学特性研究

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食品科学 2005年第3期26卷 87-93页

作者：贾春利黄卫宁 G Huang K Saitama 江南大学食品学院 Almond board of california ModestoCA95354

本文主要应用动态流变仪测定了美国加州杏仁粉(全脂和脱脂)百分含量分别为0%、12.5%、25%、37.5%和50%的面团的粘弹性模量(G″和G′)在频率和温度变化过程中所呈现出的变化趋势;以及在频率和温度相同的情况下,杏仁粉含量的变化对面团的... 详细信息

本文主要应用动态流变仪测定了美国加州杏仁粉(全脂和脱脂)百分含量分别为0%、12.5%、25%、37.5%和50%的面团的粘弹性模量(G″和G′)在频率和温度变化过程中所呈现出的变化趋势;以及在频率和温度相同的情况下,杏仁粉含量的变化对面团的G″和G′大小的影响;并进一步探索了淀粉酶处理对面团流变学特性的影响。结果表明:(1)在频率扫描过程中杏仁粉对面团的G″和G′都有明显的影响,含有全脂杏仁粉的面团的G″大于含有相同比例脱脂杏仁粉面团的G″,而含有全脂杏仁粉的面团的弹性模量G′却比含有相同比例脱脂杏仁粉的小,从而推断杏仁粉中的油脂对面团的流变学特性具有显著的影响;(2)在相同的频率时小麦粉面团的G″和G′比分别含有12.5%和25%的杏仁粉(全脂和脱脂)的面团的大,而分别含有37.5%和50%的杏仁粉的面团的G″和G′更大,这可能是由于杏仁蛋白质与小麦蛋白质发生了某种相互作用所致;(3)在升温过程中,添加全脂和脱脂杏仁粉都会使面团的G″和G′减小;在降温过程中,加入杏仁粉(全脂和脱脂)使面团的G′减小,但含有脱脂杏仁粉面团的G′大于含有全脂杏仁粉面团的G′,而加入杏仁粉对面团的G″在降温过程中的变化影响不显著;(4)在频率变化、升温和降温过程中,加入淀粉酶都会使面团的G″和G′减小。

关键词：面团体系美国加州杏仁粉粘弹性模量淀粉酶流变学

Systems research helping to meet the needs and managing the trade-offs of a changing world

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Journal of Integrative Agriculture 2015年第8期14卷 1475-1477页

作者： Peter Carberry Shu Geng LIANG Wei-li LI Ling-ling Member of JIA Editorial board International Crops Research Institute for the Semi-Arid Tropics Executive Editor-in-Chief of JIA Northwest Agriculture and Forestry University University of california at Davis Faculty of Agronomy Agricultural University of Hebei Baoding School of Agronomy Gansu Agricultural University

Facing the challenges of an increasing world population, a changing climate and ever depleting resources, agricultural intensification （Keating et al. 2010） is one of the few options for meeting the demand of food security. It is necessary to apply a dynamic and systematic approach to effectively man- age the complex agri-eco production and green processing systems. Indeed, farming systems approach for appropriate technology development and simulation modeling is a result of adopting the system thinking by the agricultural research community （Norman et al. 1995）.

关键词： helping managing agricultural challenges farming revolution symposium thinking http options

Comparison of associations of household-level and neighbourhood-level poverty markers with paediatric asthma care utilisation by race/ethnicity in an open cohort of community health centre patients

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Family Medicine and Community Health 2023年第3期11卷 86-101页

作者： Jennifer A Lucas Miguel Marino Steffani R Bailey Audree Hsu Roopradha Datta Erika Cottrell Ye Ji Kim Shakira F Suglia Andrew Bazemore John Heintzman Department of Family Medicine Oregon Health&Science UniversityPortlandOregonUSA california University of Science and Medicine ColtonCaliforniaUSA OCHIN Inc PortlandOregonUSA Department of Epidemiology Rollins School of Public HealthEmory UniversityAtlantaGeorgiaUSA American board of Family Medicine LexingtonKentuckyUSA

Objective The objective of this research was to examine how different measurements of poverty(household-level and neighborhood-level)were associated with asthma care utilisation outcomes in a community health centre setting among Latino,non-Latino black and non-Latino white ***,setting and participants We used 2012–2017 electronic health record data of an open cohort of children aged200%FPL(55%).Overall,neighbourhood poverty(<100%FPL)was associated with more asthma visits(covariate-adjusted OR 1.26,95%CI 1.12 to 1.41),and living in a low-income neighbourhood(≥100%to<200%FPL)was associated with more albuterol prescriptions(covariate-adjusted rate ratio 1.07,95%CI 1.02 to 1.13).When stratified by race/ethnicity,we saw differences in both directions in associations of household/neighbourhood income and care outcomes between *** This study enhances understanding of measurements of race/ethnicity differences in asthma care utilisation by income,revealing different associations of living in low-income neighbourhoods and households for Latino,non-Latino white and non-Latino black children with *** implies that markers of family and community poverty may both need to be considered when evaluating the association between economic status and healthcare *** to measure both kinds of poverty(family and

关键词： prescription income Latin