Analysis of observed ozone data in 2006 from five monitoring sites (Xujiahui, Chongming, Baoshan, Pudong, Jinshan) in Shanghai reveals that ozone (O_3) concentrations in Xujiahui are higher at week-ends than those on ...Analysis of observed ozone data in 2006 from five monitoring sites (Xujiahui, Chongming, Baoshan, Pudong, Jinshan) in Shanghai reveals that ozone (O_3) concentrations in Xujiahui are higher at week-ends than those on weekdays, despite the fact that emissions of ozone precursor substances, such as oxides of nitrogen (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs) are lower at weekends than those on weekdays. The possible chemical cause of ozone "weekend effect" is that NO_2/NO ratio increases at weekends by 25.61% compared with those on weekdays. In addition, because of an average 12.13% reduction in NOx (NO + NO_2) in the early morning (05:00-09:00) at weekends compared with that on weekdays, the ozone inhibition period ends 0.5 h earlier at weekends resulting in the longer duration of ozone accumulation and the higher ozone production rate. The rate of ozone production is a function of VOCs and NOx in the atmosphere. VOCs/NOx ratio in Xujiahui is 4.55 at weekends, and 4.37 on weekdays, belonging to the "NOx-limited". The increasing VOCs/NOx ratio at weekends leads to ozone enhancement from 73 ppbv to 80 ppbv, which are consistent with ozone "weekend effect" in Xujiahui. Furthermore, combining with MICAPS cloud amount data, the fact that ozone "weekend effect" in Xujiahui weakens gradually along with the increasing of cloud amount indicates that ozone photochemical production leads to ozone "weekend effect" in Xujiahui of Shanghai.展开更多
AIM:To evaluate whether weekend or nighttime admission affects prognosis of peptic ulcer bleeding despite early endoscopy.METHODS:Retrospective data collection from four referral centers,all of which had a formal out-...AIM:To evaluate whether weekend or nighttime admission affects prognosis of peptic ulcer bleeding despite early endoscopy.METHODS:Retrospective data collection from four referral centers,all of which had a formal out-of-hours emergency endoscopy service,even at weekends.A total of 388 patients with bleeding peptic ulcers who were admitted via the emergency room between January 2007 and December 2009 were enrolled.Analyzed parameters included time from patients' arrival until endoscopy,mortality,rebleeding,need for surgery and length of hospital stay.RESULTS:The weekday and weekend admission groups comprised 326 and 62 patients,respectively.There were no significant differences in baseline characteristics between the two groups,except for younger age in the weekend group.Most patients (97%) had undergone early endoscopy,which resulted in a low mortality rate regardless of point of presentation (1.8% overall vs 1.6% on the weekend).The only outcome that was worse in the weekend group was a higher rate of rebleeding (12% vs 21%,P = 0.030).However,multivariate analysis revealed nighttime admission and a high Rockall score (≥ 6) as significant independent risk factors for rebleeding,rather than weekend admission.CONCLUSION:Early endoscopy for peptic ulcer bleeding can prevent the weekend effect,and nighttime admission was identified as a novel risk factor for rebleeding,namely the nighttime effect.展开更多
AIM To compare mortality and time-to-surgery of patients admitted with hip fracture to our teaching hospital on weekdays vs weekends. METHODS Data was prospectively collected and retrospectively analysed for 816 hip f...AIM To compare mortality and time-to-surgery of patients admitted with hip fracture to our teaching hospital on weekdays vs weekends. METHODS Data was prospectively collected and retrospectively analysed for 816 hip fracture patients. Multivariate logistic regression was carried out on 3 binary outcomes(timeto-surgery < 36 h; 30-d mortality; 120-d mortality), using the explanatory variables time-of-admission; age; gender; American Society of Anesthesiologist(ASA) grade; abbreviated mental test score(AMTS); fracture type; accommodation admitted from; walking ability outdoors; accompaniment outdoors and season. RESULTS Baseline characteristics were not statistically different between those admitted on weekdays vs weekends. Weekend admission was not associated with an increased time-to-surgery(P = 0.975), 30-d mortality(P = 0.842) or 120-d mortality(P = 0.425). Gender(P = 0.028), ASA grade(P < 0.001), AMTS(P = 0.041) and accompaniment outdoors(P = 0.033) were significant covariates for 30-d mortality. Furthermore, age(P < 0.001),gender(P = 0.011), ASA grade(P < 0.001), AMTS(P < 0.001) and accompaniment outdoors(P = 0.033) all significantly influenced mortality at 120 d. ASA(P < 0.001) and season(P = 0.014) had significant effect on the odds of undergoing surgery in under 36 h.CONCLUSION Weekend admission was not associated with increased time-to-surgery or mortality in hip fracture patients. Demographic factors affect mortality in accordance with previous published reports.展开更多
Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing glob...Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing global power needs, etc. Also the diverse meteorological factors influence our environment to a great extent. Population explosion has led to remarkable increase in vehicular population. The use solely depends upon the lifestyle of the citizen. Any change in the lifestyle has a remarkable effect on the air we breathe. A comprehensive database for pollution levels from the year 2006 to 2010 was analyzed for a main traffic intersection and a non-traffic area in Delhi (India). The paper asserts that pollutant concentration levels on weekend are lower than those on weekdays (increase on Sundays with respect to weekdays is CO 2.98 times, PM2.5 1.18 times, NO 1.62 times, NO2 5.76 times, SO2 1.27 times and O3 1.15 times). The pollution levels have been found to attenuate on public holidays and weekends. Pollution can hence be related to the weekly cycle of human activities. Pollutions due to vehicular emissions on roads, rails, air or water all serve as major sources of pollution. Hence, viably possible solutions for pollution control can also be achieved by controlling the magnitude of traffic flow on roads.展开更多
Based on questionnaire survey and cross--tabulation analysis, the authors discussed relationships between emissiveness and socio--economic elements ofShanghainese in their weekend trips, including emissivenesses of di...Based on questionnaire survey and cross--tabulation analysis, the authors discussed relationships between emissiveness and socio--economic elements ofShanghainese in their weekend trips, including emissivenesses of different age group,income per month, occupations, education and family structure. Visiting rates ofrecreationists to destinations demonstrated different levels even being under a same emissiveness. In the second part of the paper, the authors described three differentspatial scales of destination choice behavior of Shanghainese to tourist sites fromwhich situated in urban area, to which located in suburb area and in neighboringprovinces. The authors also observed the perceptive evaluation of Shanghainese tothose sites they had visited or would visit in the future. Some proposals abollt sustainable urban tourism development were put forward at the end of this paper.展开更多
AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-2...AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-200 g were divided into groups as follows:(1) Control groups; and(2) weekend alcohol-consumption group: 2 d/weekly per 12 wk, at two different concentrations:(1) Group of males or females with a consumption of a solution of alcohol at 40%; and(2) group of males or females with a consumption of a solution of alcohol at 5%. At the end of the experiment, serum and liver samples were obtained. The following enzymes and metabolites were determined in serum: Alanine Aminotransferase(ALT), Aspartate Aminotransferase(AST), Lactate Dehydrogenase, and Gamma-Glutamyltransferase, and glucose, triglycerides, cholesterol, bilirubin, and albumin. Liver samples from each group were employed to analyze morphological abnormalities by light microscopy.RESULTS In all of the weekend alcohol-consumption groups, AST activity presented a significant, 10-fold rise. Regarding ALT activity, the groups with weekend alcohol consumption presented a significant increase that was six times greater. Bilirubin levels increased significantly in both groups of females. We observed a significant increase in the parameters of fatty change and inflammation due to weekend alcohol consumption. Only the group of females that consumed alcohol at 40% presented slight hepatocel ular disorganization CONCLUSION The results obtained herein provide solid evidence that weekend alcohol consumption gives rise to liver damage, demonstrated by biochemical and histological alterations, first manifested acutely, and prolonged weekend alcohol consumption can cause greater, irreversible damage.展开更多
Indoor and outdoor air samples were simultaneously collected from the largest office building in Jahra City during 57 sampling events between August 2010 and November 2011. The collected samples were analyzed for 78 v...Indoor and outdoor air samples were simultaneously collected from the largest office building in Jahra City during 57 sampling events between August 2010 and November 2011. The collected samples were analyzed for 78 volatile organic compounds (VOCs) using CO2 cryogenic preconcentration and GC/MS analysis. Of the 48 VOCs detected, the toluene concentration exceeded the recommended air quality guidelines in 2% of the outdoor samples, and the benzene concentration exceeded these guidelines in 17.5% and 19.5% of the indoor and outdoor samples, respectively. Industrial and vehicle emissions were negligible. Emissions from oil fields, various crude oil production and flaring activities in the north were major sources of VOCs in the ambient air. The VOC profiles;seasonal, monthly, and weekday/weekend variations;and their effects on ozone formation potentials are discussed. The results indicate that the most abundant class of chemical compounds was oxygenated compounds, of which acetone, acetaldehyde, propanal, methanol, ethanol, and 2-propanol were the most dominant species. Propene and toluene were the most abundant species of aliphatic and aromatic hydrocarbons, respectively.展开更多
AIM:To evaluate the"weekend effect"on outcomes in patient admitted on the weekend for upper gastrointestinal bleeding(UGIB).METHODS:A comprehensive search was performed(March 2014).Studies comparing weekend ...AIM:To evaluate the"weekend effect"on outcomes in patient admitted on the weekend for upper gastrointestinal bleeding(UGIB).METHODS:A comprehensive search was performed(March 2014).Studies comparing weekend and weekday endoscopy in patients with UGIB were included.All studies had at least 2 of 3 primary outcomes which included:mortality,need for surgery,time to endoscopy,endoscopy on admission day,and length of hospital stay.Three authors individually extracted data.Metaanalysis was performed using pooled estimates with odds ratio or mean difference by fixed and random effects models.RESULTS:Eleven studies met the inclusion criteria.Patients admitted with UGIB on the weekend exhibited a statistically significant increase in mortality(OR=1.13;95%CI:1.06-1.20;P<0.01),need for surgery(OR=2.46;95%CI:1.51-3.99;P<0.01),and time to endoscopy(MD 2.68;95%CI:0.17-5.20;P=0.04)as compared to patients admitted with UGIB on a weekday.Furthermore,patients with UGIB admitted on weekend experienced statistically significant less endoscopy on day of admission(OR=0.72;95%CI:0.62-0.85;P<0.01).No difference was noted between the two groups for length of hospital stay(MD-1.29;95%CI:-3.03-0.45;P=0.15).CONCLUSION:A weekend effect seems to be apparent in patients with UGIB with significantly poorer outcomes.展开更多
基金the National Natural Science Foundation of China (Grant Nos. 40575060 and 40705046)the Special Research Project of China Meteorological Bureau
文摘Analysis of observed ozone data in 2006 from five monitoring sites (Xujiahui, Chongming, Baoshan, Pudong, Jinshan) in Shanghai reveals that ozone (O_3) concentrations in Xujiahui are higher at week-ends than those on weekdays, despite the fact that emissions of ozone precursor substances, such as oxides of nitrogen (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs) are lower at weekends than those on weekdays. The possible chemical cause of ozone "weekend effect" is that NO_2/NO ratio increases at weekends by 25.61% compared with those on weekdays. In addition, because of an average 12.13% reduction in NOx (NO + NO_2) in the early morning (05:00-09:00) at weekends compared with that on weekdays, the ozone inhibition period ends 0.5 h earlier at weekends resulting in the longer duration of ozone accumulation and the higher ozone production rate. The rate of ozone production is a function of VOCs and NOx in the atmosphere. VOCs/NOx ratio in Xujiahui is 4.55 at weekends, and 4.37 on weekdays, belonging to the "NOx-limited". The increasing VOCs/NOx ratio at weekends leads to ozone enhancement from 73 ppbv to 80 ppbv, which are consistent with ozone "weekend effect" in Xujiahui. Furthermore, combining with MICAPS cloud amount data, the fact that ozone "weekend effect" in Xujiahui weakens gradually along with the increasing of cloud amount indicates that ozone photochemical production leads to ozone "weekend effect" in Xujiahui of Shanghai.
文摘AIM:To evaluate whether weekend or nighttime admission affects prognosis of peptic ulcer bleeding despite early endoscopy.METHODS:Retrospective data collection from four referral centers,all of which had a formal out-of-hours emergency endoscopy service,even at weekends.A total of 388 patients with bleeding peptic ulcers who were admitted via the emergency room between January 2007 and December 2009 were enrolled.Analyzed parameters included time from patients' arrival until endoscopy,mortality,rebleeding,need for surgery and length of hospital stay.RESULTS:The weekday and weekend admission groups comprised 326 and 62 patients,respectively.There were no significant differences in baseline characteristics between the two groups,except for younger age in the weekend group.Most patients (97%) had undergone early endoscopy,which resulted in a low mortality rate regardless of point of presentation (1.8% overall vs 1.6% on the weekend).The only outcome that was worse in the weekend group was a higher rate of rebleeding (12% vs 21%,P = 0.030).However,multivariate analysis revealed nighttime admission and a high Rockall score (≥ 6) as significant independent risk factors for rebleeding,rather than weekend admission.CONCLUSION:Early endoscopy for peptic ulcer bleeding can prevent the weekend effect,and nighttime admission was identified as a novel risk factor for rebleeding,namely the nighttime effect.
文摘AIM To compare mortality and time-to-surgery of patients admitted with hip fracture to our teaching hospital on weekdays vs weekends. METHODS Data was prospectively collected and retrospectively analysed for 816 hip fracture patients. Multivariate logistic regression was carried out on 3 binary outcomes(timeto-surgery < 36 h; 30-d mortality; 120-d mortality), using the explanatory variables time-of-admission; age; gender; American Society of Anesthesiologist(ASA) grade; abbreviated mental test score(AMTS); fracture type; accommodation admitted from; walking ability outdoors; accompaniment outdoors and season. RESULTS Baseline characteristics were not statistically different between those admitted on weekdays vs weekends. Weekend admission was not associated with an increased time-to-surgery(P = 0.975), 30-d mortality(P = 0.842) or 120-d mortality(P = 0.425). Gender(P = 0.028), ASA grade(P < 0.001), AMTS(P = 0.041) and accompaniment outdoors(P = 0.033) were significant covariates for 30-d mortality. Furthermore, age(P < 0.001),gender(P = 0.011), ASA grade(P < 0.001), AMTS(P < 0.001) and accompaniment outdoors(P = 0.033) all significantly influenced mortality at 120 d. ASA(P < 0.001) and season(P = 0.014) had significant effect on the odds of undergoing surgery in under 36 h.CONCLUSION Weekend admission was not associated with increased time-to-surgery or mortality in hip fracture patients. Demographic factors affect mortality in accordance with previous published reports.
文摘Air Pollution is an escalating problem worldwide fuelled by increasing anthropogenic activities, speedy development, rapid industrialization, transportation, superfluous use of fossil fuel consumption, increasing global power needs, etc. Also the diverse meteorological factors influence our environment to a great extent. Population explosion has led to remarkable increase in vehicular population. The use solely depends upon the lifestyle of the citizen. Any change in the lifestyle has a remarkable effect on the air we breathe. A comprehensive database for pollution levels from the year 2006 to 2010 was analyzed for a main traffic intersection and a non-traffic area in Delhi (India). The paper asserts that pollutant concentration levels on weekend are lower than those on weekdays (increase on Sundays with respect to weekdays is CO 2.98 times, PM2.5 1.18 times, NO 1.62 times, NO2 5.76 times, SO2 1.27 times and O3 1.15 times). The pollution levels have been found to attenuate on public holidays and weekends. Pollution can hence be related to the weekly cycle of human activities. Pollutions due to vehicular emissions on roads, rails, air or water all serve as major sources of pollution. Hence, viably possible solutions for pollution control can also be achieved by controlling the magnitude of traffic flow on roads.
文摘Based on questionnaire survey and cross--tabulation analysis, the authors discussed relationships between emissiveness and socio--economic elements ofShanghainese in their weekend trips, including emissivenesses of different age group,income per month, occupations, education and family structure. Visiting rates ofrecreationists to destinations demonstrated different levels even being under a same emissiveness. In the second part of the paper, the authors described three differentspatial scales of destination choice behavior of Shanghainese to tourist sites fromwhich situated in urban area, to which located in suburb area and in neighboringprovinces. The authors also observed the perceptive evaluation of Shanghainese tothose sites they had visited or would visit in the future. Some proposals abollt sustainable urban tourism development were put forward at the end of this paper.
文摘AIM To examine the association between weekend alcohol consumption and the biochemical and histological alterations at two different concentrations of alcohol in both genders in rats.METHODS Wistar rats weighing 170-200 g were divided into groups as follows:(1) Control groups; and(2) weekend alcohol-consumption group: 2 d/weekly per 12 wk, at two different concentrations:(1) Group of males or females with a consumption of a solution of alcohol at 40%; and(2) group of males or females with a consumption of a solution of alcohol at 5%. At the end of the experiment, serum and liver samples were obtained. The following enzymes and metabolites were determined in serum: Alanine Aminotransferase(ALT), Aspartate Aminotransferase(AST), Lactate Dehydrogenase, and Gamma-Glutamyltransferase, and glucose, triglycerides, cholesterol, bilirubin, and albumin. Liver samples from each group were employed to analyze morphological abnormalities by light microscopy.RESULTS In all of the weekend alcohol-consumption groups, AST activity presented a significant, 10-fold rise. Regarding ALT activity, the groups with weekend alcohol consumption presented a significant increase that was six times greater. Bilirubin levels increased significantly in both groups of females. We observed a significant increase in the parameters of fatty change and inflammation due to weekend alcohol consumption. Only the group of females that consumed alcohol at 40% presented slight hepatocel ular disorganization CONCLUSION The results obtained herein provide solid evidence that weekend alcohol consumption gives rise to liver damage, demonstrated by biochemical and histological alterations, first manifested acutely, and prolonged weekend alcohol consumption can cause greater, irreversible damage.
文摘Indoor and outdoor air samples were simultaneously collected from the largest office building in Jahra City during 57 sampling events between August 2010 and November 2011. The collected samples were analyzed for 78 volatile organic compounds (VOCs) using CO2 cryogenic preconcentration and GC/MS analysis. Of the 48 VOCs detected, the toluene concentration exceeded the recommended air quality guidelines in 2% of the outdoor samples, and the benzene concentration exceeded these guidelines in 17.5% and 19.5% of the indoor and outdoor samples, respectively. Industrial and vehicle emissions were negligible. Emissions from oil fields, various crude oil production and flaring activities in the north were major sources of VOCs in the ambient air. The VOC profiles;seasonal, monthly, and weekday/weekend variations;and their effects on ozone formation potentials are discussed. The results indicate that the most abundant class of chemical compounds was oxygenated compounds, of which acetone, acetaldehyde, propanal, methanol, ethanol, and 2-propanol were the most dominant species. Propene and toluene were the most abundant species of aliphatic and aromatic hydrocarbons, respectively.
文摘AIM:To evaluate the"weekend effect"on outcomes in patient admitted on the weekend for upper gastrointestinal bleeding(UGIB).METHODS:A comprehensive search was performed(March 2014).Studies comparing weekend and weekday endoscopy in patients with UGIB were included.All studies had at least 2 of 3 primary outcomes which included:mortality,need for surgery,time to endoscopy,endoscopy on admission day,and length of hospital stay.Three authors individually extracted data.Metaanalysis was performed using pooled estimates with odds ratio or mean difference by fixed and random effects models.RESULTS:Eleven studies met the inclusion criteria.Patients admitted with UGIB on the weekend exhibited a statistically significant increase in mortality(OR=1.13;95%CI:1.06-1.20;P<0.01),need for surgery(OR=2.46;95%CI:1.51-3.99;P<0.01),and time to endoscopy(MD 2.68;95%CI:0.17-5.20;P=0.04)as compared to patients admitted with UGIB on a weekday.Furthermore,patients with UGIB admitted on weekend experienced statistically significant less endoscopy on day of admission(OR=0.72;95%CI:0.62-0.85;P<0.01).No difference was noted between the two groups for length of hospital stay(MD-1.29;95%CI:-3.03-0.45;P=0.15).CONCLUSION:A weekend effect seems to be apparent in patients with UGIB with significantly poorer outcomes.
