Recently, tropospheric ozone has become a public health concern worldwide, along with the continuous battle against ambient fine particulate matter in countries like China. In this study, we investigate the impact of indoor ozone pollution using seven materials categorized as either wood-based panels or synthetic fibers, which were freely-stored in an office/lab environment. Most materials were considered as used and aged more than 1–2 years. An experimental apparatus was used to study ozone deposition and detect volatile organic compound (VOC) emissions from the specimens when exposed to ozone at three concentration levels: <10, 100, and 300 ppb. A simplified model is proposed to discuss ventilation requirements based on a standard room. We found that the mean ozone deposition velocities from the seven materials ranged from 0.005 to 0.062 cm·s−1. Both the engineering wood and some of the synthetic fibers were, moreover, prone to ozone deposition. Second, 15 VOCs were found in the sampling air from a 24-VOC target list after ozone exposure. The emission rates of the VOCs from all seven materials were then determined. Third, when the ozone concentration in the outdoor air is not severely high, it is possible to use ventilation to maintain acceptable indoor air quality.
The paper presents the results of a study conducted to investigate indoor air quality within residential dwellings in Lao PDR. Results from PM10, CO, and NO2 measurements inside 167 dwellings in Lao PDR over a five month period (December 2005-April 2006) are discussed as a function of household characteristics and occupant activities. Extremely high PM10 and NO2 concentrations (12 h mean PM10 concentrations 1275 ± 98 μg m−3 and 1183 ± 99 μg m−3 in Vientiane and Bolikhamxay provinces, respectively; 12 h mean NO2 concentrations 1210 ± 94 μg m−3 and 561 ± 45 μg m−3 in Vientiane and Bolikhamxay, respectively) were measured within the dwellings. Correlations, ANOVA analysis (univariate and multivariate), and linear regression results suggest a substantial contribution from cooking and smoking. The PM10 concentrations were significantly higher in houses without a chimney compared to houses in which cooking occurred on a stove with a chimney. However, no significant differences in pollutant concentrations were observed as a function of cooking location. Furthermore, PM10 and NO2 concentrations were higher in houses in which smoking occurred, suggestive of a relationship between increased indoor concentrations and smoking (0.05 < p < 0.10). Resuspension of dust from soil floors was another significant source of PM10 inside the house (634 μg m−3, p < 0.05).
Fine particulate matter (with aerodynamic diameter ≤2.5 µm, PM2.5) causes huge disease burden worldwide. However, evidence is still inadequate and inconsistent on the relationships between PM2.5 constituents and mortality, especially in low resource settings. To evaluate the impact of PM2.5 constituents on cause-specific mortality in China. We obtained daily mortality data for 161 communities in 2011–2013 from the Disease Surveillance Point system in China. Daily concentrations of major PM2.5 constituents, including organic carbon (OC), elemental carbon (EC), sulphate (SO42-), nitrate (NO3-) and ammonium (NH4+), were estimated by using the modified Community Multiscale Air Quality model. For each community, we applied quasi-Poisson regression and polynomial distributed lag models to estimate the effects of PM2.5 constituents on cause-specific mortality. Then, the pooled effect estimates were calculated by a random-effect meta-analysis based on the restricted maximum likelihood estimation. Stratification analyses were performed by region, gender, age group and education level to identify the vulnerable populations. Each interquartile range change of EC, OC, SO42-, NO3- and NH4+ at lag 0–3 day was associated with increments in non-accidental mortality of 0.45% (95%CI: 0.21, 0.69), 1.43% (0.97, 1.89), 0.71% (0.28, 1.15), 0.70% (0.10, 1.30) and 0.95% (0.39, 1.51), respectively. The associations were stronger for the deaths from cardiovascular disease and myocardial infarction, the elderly, illiterates, and people living in the South region. Our findings suggest positive associations between PM2.5 constituents and cause-specific mortality, particularly for myocardial infarction.
Toluene is a typical anthropogenic pollutant that has profound impacts on air quality, climate change, and human health, but its sources and sinks over forests surrounding megacities remain unclear. The Nanling Mountains (NM) is a large subtropical forest and is adjacent to the Pearl River Delta (PRD) region, a well-known hotspot for toluene emissions in southern China. However, unexpectedly low toluene concentrations (0.16 ± 0.20 ppbv) were observed at a mountaintop site in NM during a typical photochemical period. A backward trajectory analysis categorized air masses received at the site into three groups, namely, air masses from the PRD, those from central China, and from clean areas. The results revealed more abundant toluene and its key oxidation products, for example, benzaldehyde in air masses mixed with urban plumes from the PRD. Furthermore, a more than three times faster degradation rate of toluene was found in this category of air masses, indicating more photochemical consumption in NM under PRD outflow disturbance. Compared to the categorized clean and central China plumes, the simulated OH peak level in the PRD plumes (15.8 ± 2.2 × 106 molecule cm-3) increased by approximately 30% and 55%, respectively, and was significantly higher than the reported values at other background sites worldwide. The degradation of toluene in the PRD plumes was most likely accelerated by increased atmospheric oxidative capacity, which was supported by isoprene ozonolysis reactions. Our results indicate that receptor forests around megacities are not only highly polluted by urban plumes, but also play key roles in environmental safety by accelerating the degradation rate of anthropogenic pollutants.
Femtosecond fluorescence upconversion and picosecond time-correlated single-photon counting fluorescence experiments for bridged and unbridged ionic styryl dye compounds in polar solvents are reported. The measured fluorescence transients reveal S2 → S1 internal conversion (IC) with a typical time of 300 fs, independent of bridged or unbridged structure. The lifetime of the relaxed emissive S1 state differs considerably for the bridged and unbridged structures: when the styryl-group single bonds are unbridged, the S1-state lifetime is only about 20 ps and the non-radiative decay to the ground state is very effective. When both single bonds of the styryl dye are chemically bridged and only the double bond is free to rotate, the fast decay is suppressed and the lifetime becomes about 2 ns. In addition, the fluorescence of the ionic styryl dyes shows picosecond transient behavior that is attributed to vibrational cooling in the excited S1 state. Finally, a qualitative discussion is given of the influence of the donor–acceptor strength of the styryl dye compounds on the polymethine and stilbenoid character of the S1 state and how this affects the effectiveness of the single- and double-bond twisting relaxation pathways for this state.
Estudar o impacto em linfócitos causado pelo uso da dexmedetomidina associada à morfina para analgesia pós‐toracotomia. Um total de 118 pacientes utilizando Analgesia Intravenosa Controlada pelo Paciente (AICP) pós‐toracotomia em nosso hospital, de março de 2016 a julho de 2018, foram selecionados aleatoriamente e divididos em dois grupos: o Grupo Combinado [COM, 57 pacientes que receberam dexmedetomidina (1,0 μg.kg‐1 de peso corpóreo) associada à morfina (0,48 mg.kg‐1 de peso corpóreo)] e o Grupo Morfina [MOR, 61 pacientes, que receberam somente morfina (0,48 mg.kg‐)]. Os valores dos subconjuntos de linfócitos (CD3+, CD4+ e CD8+) e das células NK no sangue periférico desses dois grupos foram medidos por citometria de fluxo FACSCalibur em diferentes momentos do estudo [antes da indução anestésica (T0), imediatamente após extubação traqueal (T1), 12 horas após a cirurgia (T2), 24 horas após a cirurgia (T3), 48 horas após a cirurgia (T4), 72 horas após a cirurgia (T5) e 7 dias após a cirurgia (T6)]. As doses de morfina do momento T3 ao T5 e as reações adversas entre os dois grupos também foram registradas e comparadas. O nível de CD3+ e a razão CD4+/CD8+ de T2 a T5, e o nível de CD4+ e as células NK de T3 a T5 do Grupo COM foram significantemente maiores (p < 0,05) quando comparados ao Grupo MOR. A dose de morfina no pós‐operatório e a incidência de prurido, náusea e vômito no pós‐operatório foram significantemente menores no grupo MOR (p < 0,05). Dexmedetomidina combinada com morfina para AICP no período pós‐toracotomia pode melhorar a função dos linfócitos, reduzir o consumo de morfina e diminuir reações adversas durante a analgesia. This study aimed to investigate the impact of post‐thoracotomy analgesia with dexmedetomidine and morphine on immunocytes. A total of 118 patients with post‐thoracotomy Patient‐Controlled Intravenous Analgesia (PCIA) in our hospital from March 2016 to July 2018 were randomly selected and divided into the Composite (COM) Group (57 patients administered with dexmedetomidine [1.0 μg.kg‐1 body weight] and morphine [0.48 mg.kg‐1 body weight]) and the Morphine (MOR) Group (61 patients administered with morphine [0.48 mg.kg‐1]). The values of lymphocyte subsets (CD3+, CD4+, and CD8+) and Natural Killer cells in the peripheral blood of these two groups were detected by FACSCalibur flow cytometry at different time points (before anesthesia induction [T0], immediately after tracheal extubation [T1], 12 hours after surgery [T2], 24 hours after surgery [T3], 48 hours after surgery [T4], 72 hours after surgery [T5], and 7 days after surgery [T6]). The doses of morphine at T3 to T5 and the adverse reactions between the two groups were also recorded and compared. The CD3+ level and the CD4+/CD8+ ratio at T2 to T5 and the CD4+ level and NK cells at T3 to T5 were significantly higher in the COM Group than in the MOR Group (p < 0.05). The postoperative morphine dose and the incidence of postoperative itching, nausea, and vomiting were significantly lower in the COM Group than in the MOR Group (p < 0.05). Dexmedetomidine combined with morphine for post‐thoracotomy PCIA can improve the function of immunocytes, reduce morphine consumption, and reduce the adverse reactions during analgesia induction.
This study aimed to investigate the impact of post-thoracotomy analgesia with dexmedetomidine and morphine on immunocytes. A total of 118 patients with post-thoracotomy Patient-Controlled Intravenous Analgesia (PCIA) in our hospital from March 2016 to July 2018 were randomly selected and divided into the Composite (COM) Group (57 patients administered with dexmedetomidine [1.0 μg.kg-1 body weight] and morphine [0.48 mg.kg-1 body weight]) and the Morphine (MOR) group (61 patients administered with morphine [0.48 mg.kg-1]). The values of lymphocyte subsets (CD3+, CD4+, and CD8+) and Natural Killer cells in the peripheral blood of these two groups were detected by FACSCalibur flow cytometry at different time points (before anesthesia induction [T0], immediately after tracheal extubation [T1], 12 hours after surgery [T2], 24 hours after surgery [T3], 48 hours after surgery [T4], 72 hours after surgery [T5], and 7 days after surgery [T6]). The doses of morphine at T3 to T5 and the adverse reactions between the two groups were also recorded and compared. The CD3+ level and the CD4+/CD8+ ratio at T2 to T5 and the CD4+ level and NK cells at T3 to T5 were significantly higher in the COM Group than in the MOR Group (p< 0.05). The postoperative morphine dose and the incidence of postoperative itching, nausea, and vomiting were significantly lower in the COM Group than in the MOR Group (p< 0.05). Dexmedetomidine combined with morphine for post-thoracotomy PCIA can improve the function of immunocytes, reduce morphine consumption, and reduce the adverse reactions during analgesia induction. Estudar o impacto em linfócitos causado pelo uso da dexmedetomidina associada à morfina para analgesia pós-toracotomia. Um total de 118 pacientes utilizando Analgesia Intravenosa Controlada pelo Paciente (AICP) pós-toracotomia em nosso hospital de Março de 2016 a Julho de 2018 foram selecionados aleatoriamente e divididos em dois grupos: o Grupo Gombinado [COM, 57 pacientes que receberam dexmedetomidina (1,0 μg.kg-1 de peso corpóreo) associada à morfina (0,48 mg.kg-1 de peso corpóreo)] e o Grupo Morfina [MOR, 61 pacientes, que receberam somente morfina (0,48 mg.kg-1)]. Os valores dos subconjuntos de linfócitos (CD3+, CD4+ e CD8+) e das células NK no sangue periférico desses dois grupos foram medidos por citometria de fluxo FACSCalibur em diferentes momentos do estudo [antes da indução anestésica (T0), imediatamente após extubação traqueal (T1), 12 horas após a cirurgia (T2), 24 horas após a cirurgia (T3), 48 horas após a cirurgia (T4), 72 horas após a cirurgia (T5) e 7 dias após a cirurgia (T6)]. As doses de morfina do momento T3 ao T5 e as reações adversas entre os dois grupos também foram registradas e comparadas. O nível de CD3+ e a razão CD4+/CD8+ de T2 a T5, e o nível de CD4+ e as células NK de T3 a T5 do Grupo COM foram significantemente maiores (p < 0,05), quando comparados ao Grupo MOR. A dose de morfina no pós-operatório e a incidência de prurido, náusea e vômito no pós-operatório foram significantemente menores no grupo MOR (p < 0,05). Dexmedetomidina combinada com morfina para AICP no período pós-toracotomia pode melhorar a função dos linfócitos, reduzir o consumo de morfina e diminuir reações adversas durante a analgesia.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)
'/%3e%3c/defs%3e%3cpath fill='%23012169' d='M0 0h10080v5040H0z'/%3e%3cpath stroke='%23fff' stroke-width='.6' d='m0 0 6 3m0-3L0 3' clip-path='url(%23b)' transform='scale(840)'/%3e%3cpath stroke='%23e4002b' stroke-width='.4' d='m0 0 6 3m0-3L0 3' clip-path='url(%23c)' transform='scale(840)'/%3e%3cpath stroke='%23fff' stroke-width='840' d='M2520 0v2520M0 1260h5040'/%3e%3cpath stroke='%23e4002b' stroke-width='504' d='M2520 0v2520M0 1260h5040'/%3e%3cg fill='%23fff'%3e%3cuse xlink:href='%23d' x='2520' y='3780'/%3e%3cuse xlink:href='%23a' x='7560' y='4200'/%3e%3cuse xlink:href='%23a' x='6300' y='2205'/%3e%3cuse xlink:href='%23a' x='7560' y='840'/%3e%3cuse xlink:href='%23a' x='8680' y='1869'/%3e%3cuse xlink:href='%23e' x='8064' y='2730'/%3e%3c/g%3e%3c/svg%3e)