The occurrence of extreme weather conditions appears on the rise under current climate change conditions, resulting in more frequent and severe floods. The devastating floods in southern China in 2010 and eastern Australia 2010–2011, serve as a solemn testimony to that notion. Accompanying the excess runoffs, elevated amount of terrigenous materials, including nutrients for microalgae, are discharged to the coastal ocean. However, how these floods and the materials they carry affect the coastal ocean ecosystem is still poorly understood. Yangtze River (aka Changjiang), which is the largest river in the Eurasian continent, flows eastward and empties into the East China Sea. Since the early twentieth century, serious overflows of the Changjiang have occurred four times. During the two most recent ones in July 1998 and 2010, we found total primary production in the East China Sea reaching 147 × 103 tons carbon per day, which may support fisheries catch as high as 410 × 103 tons per month, about triple the amount during non‐flooding periods based on direct field oceanographic observations. As the frequencies of floods increase world wide as a result of climate change, the flood‐induced biological production could be a silver lining to the hydrological hazards and human and property losses inflicted by excessive precipitations.
We attempted to identify Asian dust (AD) events between February 2002 and February 2007 in northern Taiwan using aerosol Al measurements. We subsequently used the results to propose a criterion for defining AD events. A total of 30 AD events were detected based on Al spiking concentrations, and these occurred frequently in 2002 and 2006. The dust plumes that were identified occurred between November and April, which were concentrated in February, March, and April. There were 35 dusty days, which accounted for 1.89% of the whole study period, and for 3.75% when considering only November through April. The seasonality of atmospheric Al is quite evident, reaching a maximum in spring and winter and a minimum in summer. This pattern is related to the long‐range transport of AD in the northeasterly monsoon and the cease of AD contributions, the efficient removal by heavy rain, and effective mixing in summer. According to air‐mass trajectory analysis, the primary dust regions are located in and around the Gobi Desert and Loess Plateau. The geometric mean concentration of the data set excluding the AD cases is 502 ng m−3 with a geometric standard deviation (GSD) of 2.8. On the basis of our success in identifying the major AD events, the “geometric mean ×2 GSD” (i.e., 2800 ng m−3 in our study area) is proposed as a straightforward criterion to define the significant AD event. As such, the statistic‐based criterion could be applicable for other areas.
WHAT'S KNOWN ON THIS SUBJECT: Major depression is common among adolescents. The PHQ-9 has good sensitivity and specificity for detecting depression among adolescents in primary care settings. However, no study has examined the psychometric properties of the PHQ-9 among Chinese adolescents in school settings. WHAT THIS STUDY ADDS:This is the first study to validate the use of the PHQ-9, Patient Health Questionnaire-2 item, and Patient Health Questionnaire-1 item among Chinese adolescents in Taiwan. The PHQ-9 and its 2 subscales have good sensitivity and specificity for detecting depression among school adolescents.abstract OBJECTIVE: The aim of this study was to determine the reliability and validity of a Chinese version of the Patient Health Questionnaire-9 item (PHQ-9) and its 2 subscales (1 item and 2 items) for the screening of major depressive disorder (MDD) among adolescents in Taiwan.METHODS: A total of 2257 adolescents were recruited from high schools in Taipei. The participants completed assessments including demographic information, the Chinese version of the PHQ-9, and the Rosenberg Self-Esteem Scale, and data on the number of physical illnesses and mental health service utilizations were recorded. Among them, 430 were retested using the PHQ-9 within 2 weeks. Child psychiatrists interviewed a subsample of the adolescents (n = 165) using the Kiddie-Schedule for Affective Disorder and Schizophrenia Epidemiological Version as the criterion standard. RESULTS:The PHQ-9 had good internal consistency (a = 0.84) and acceptable test-retest reliability (0.80). The participants with higher PHQ-9 scores were more likely to have MDD. Principal component factor analysis of the PHQ-9 yielded a 1-factor structure, which accounted for 45.3% of the variance. A PHQ-9 score $15 had a sensitivity of 0.72 and a specificity of 0.95 for recognizing MDD. The area under the receiver operating characteristic curve was 0.90. The screening accuracy of the 2 subscales was also satisfactory, with a Patient Health Questionnaire-2 item cutoff of $3 being 94.4% sensitive and 82.5% specific and a Patient Health Questionnaire-1 item cutoff of $2 being 61.1% sensitive and 87.7% specific. CONCLUSIONS:The PHQ-9 and its 2 subscales appear to be reliable and valid for detecting MDD among ethnic Chinese adolescents in Taiwan.
Passivation is a challenging issue for the oxide thin-film transistor (TFT) technologies because it requires prolonged high-temperature annealing treatments to remedy defects produced in the process, which greatly limits its manufacturability as well as its compatibility with temperature-sensitive materials such as flexible plastic substrates. This study investigates the defect-formation mechanisms incurred by atomic layer deposition (ALD) passivation processes on ZnO TFTs, based on which we demonstrate for the first time degradation-free passivation of ZnO TFTs by a TiO2/Al2O3 nanolaminated (TAO) film deposited by a low-temperature (110 °C) ALD process. By combining the TAO passivation film with ALD dielectric and channel layers into an integrated low-temperature ALD process, we successfully fabricate flexible ZnO TFTs on plastics. Thanks to the exceptional gas-barrier property of the TAO film (water vapor transmission rate (WVTR)<10(-6) g m(-2) day(-1)) as well as the defect-free nature of the ALD dielectric and ZnO channel layers, the TFTs exhibit excellent device performance with high stability and flexibility: field-effect mobility>20 cm2 V(-1) s(-1), subthreshold swing<0.4 V decade(-1) after extended bias-stressing (>10,000 s), air-storage (>1200 h), and bending (1.3 cm radius for 1000 times).
[1] Dichotomous (PM 2.5 -10 and PM 2.5 modes) and size-resolved marine aerosols collected during the northeastern monsoon on two wintertime cruises in the subtropical South China Sea (SCS) were analyzed for water-soluble ions. During the sampling periods the study region was under the influence of strong pollution originating primarily from the Asian continent. Elevated levels of non-sea-salt sulfate and ammonium ions of up to 4.5 and 1.2 mg/m 3 , respectively, were observed, indicating that the SCS is now substantially contaminated by massive amounts of air pollutants most likely from China and South/Southeast Asia. The non-sea-salt sulfate to nitrate mass ratios reaching 3.8 ± 1.9 are much larger than those (approximately 2) in and around East Asia and the western Pacific Ocean, suggesting that the Asian outflow aerosols measured in the SCS experienced different traveling history from those in the vicinity of source regions. High chloride depletion (Cl-depletion) measured in the SCS marine aerosols was, on average, 30% for coarse-mode particles and nearly 90% for fine-mode particles. Cldepletion is size-dependent, and maximizes in submicrometer particles (i.e., Cl has almost been completely lost). Acid displacement is responsible for the observed high Cldepletion: nitrate substitution accounts for the coarse-mode depletion, whereas sulfate substitution accounts for the fine-mode depletion. The acid displacement of sea salt aerosols may be related to a variety of factors, especially the substantial air pollution, which is discussed in detail in this paper. On cloudy/rainy days, fine-mode aerosol samples have moderate Cl-depletion (i.e., $40-50%), in contrast to nearly complete Cl loss on sunny days, presumably indicating that photochemical reactions would play a key role in the Cl-deficit; however, it merits further investigation as the available samples were limited.
[1] Both the Yangtze River Delta (YRD) and the Pearl River Delta (PRD), the two most rapidly developing areas in eastern China, have suffered from serious air pollution, and thus, numerous investigations were devoted to studying these problems. Other areas in eastern China have received less attention despite similar rapid development in their industries and economy. In this study, we analyzed air-quality data from Kinmen Island (24°27′26″N, 118°19′36″E) located off Fujian Province and between the two above-mentioned deltas. Our results clearly show that the study area is experiencing serious air quality deterioration. Particularly, high levels of suspended particulate matter (PM) were observed during winter, when the northeasterly monsoon prevails. For example, concentrations of wintertime PM 10 (particles ≤ 10 mm in diameter) frequently exceeded 100 mg/m 3 in the last three years. In addition to the air-quality data analysis, aerosol samples were collected between 22 November 2007 and 6 March 2008 and subjected to chemical analyses of various species. Our findings show that the three principal PM components include organic, mineral, and sulfate species with moderate to minor fractions of nitrate, sea salt, elemental carbon, and trace metal oxides. The high PM levels observed over the island may be partly attributed to the transport from a mixed-type industrial area located ∼40 km northeast of Kinmen. Our study could partially fill the air quality data gap between the YRD and PRD regions, and highlight the alarming fact that air pollution has gradually expanded along eastern China's coastal zone.Citation: Hsu, S. C., et al. (2010), High wintertime particulate matter pollution over an offshore island (Kinmen) off
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