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1.
An integrated pest management program warrants the use of chemicals which are target specific. Juvenile Hormone Analogues (JHA), due to their insecticidal, morphogenetic and chemosterilant effects they cause by disturbing the normal development of an insect species, are commonly known as neopesticides. These are species specific, less toxic and get degraded to non‐toxic compounds in a short time period. Two such chemicals viz. 2‐(4'‐ethyl phenyl)‐6 chloro‐6 methyl heptane, and 1‐(4'‐ethyl phenyl)‐7 chloro‐3, 7 ‐dimethyl octane, were tested for their biological activities. Last larval instars of three insect species, Episyrphus balteatus (De Geer), Epilachna duodecimpunctata M. and Tribolium castaneum Herbst, were treated. Different concentrations were tried to evaluate ED50. 1‐(4'‐ ethyl phenyl)‐ 7‐chloro‐3, 7‐dimethyl octane showed comparatively more biological activity and was more effective. Biological activity was determined by comparing the number of supernumeraries, intermediates and pharated produced after treatment.  相似文献   

2.
R. Liu  Y. Jiang  Q. Li  S. K. Hammond 《Indoor air》2014,24(4):339-349
Field observation of patron smoking behaviors and multiple sampling approaches were conducted in 79 restaurants and bars in Beijing, 2010, 2 years after implementing the governmental smoking regulations. Smoking was observed in 30 visits to 22 of the 37 nominal non‐smoking venues during peak patronage times and six visits to four of the 14 nominal non‐smoking sections. The median area secondhand smoke (SHS) concentrations during peak patronage time were 27, 15, 43, and 40 μg/m3 in nominal non‐smoking venues, non‐smoking sections, smoking sections, and smoking venues, respectively, as indicated by the difference between indoor and outdoor PM2.5 levels; and 1.4, 0.6, 1.7, and 2.7 μg/m3, respectively, as indicated by airborne nicotine. In the 27 venues with sampling of different approaches and over different time periods, the median nicotine concentration was 1.8 μg/m3 by one‐hour peak patronage‐time sampling, 1.1 μg/m3 by 1‐day active area sampling, 2.5 μg/m3 by 1‐day personal sampling, and 2.3 μg/m3 by week‐long passive sampling. No significant differences in nicotine levels were observed among venues/sections with different nominal smoking policies by all sampling approaches except during peak patronage time. This study showed that the 2008 Beijing governmental smoking restriction has been poorly implemented, and SHS exposures in Beijing restaurants and bars remain high.  相似文献   

3.
We estimated the impact of a smoke‐free workplace bylaw on non‐smoking bar workers' health in Ontario, Canada. We measured bar workers' urine cotinine before (= 99) and after (= 91) a 2004 smoke‐free workplace bylaw. Using pharmacokinetic and epidemiological models, we estimated workers' fine‐particle (PM2.5) air pollution exposure and mortality risks from workplace secondhand smoke (SHS). workers' pre‐law geometric mean cotinine was 10.3 ng/ml; post‐law dose declined 70% to 3.10 ng/ml and reported work hours of exposure by 90%. Pre‐law, 97% of workers' doses exceeded the 90th percentile for Canadians of working age. Pre‐law‐estimated 8‐h average workplace PM2.5 exposure from SHS was 419 μg/m3 or ‘Very Poor’ air quality, while outdoor PM2.5 levels averaged 7 μg/m3, ‘Very Good’ air quality by Canadian Air Quality Standards. We estimated that the bar workers' annual mortality rate from workplace SHS exposure was 102 deaths per 100 000 persons. This was 2.4 times the occupational disease fatality rate for all Ontario workers. We estimated that half to two‐thirds of the 10 620 Ontario bar workers were non‐smokers. Accordingly, Ontario's smoke‐free law saved an estimated 5–7 non‐smoking bar workers' lives annually, valued at CA $50 million to $68 million (US $49 million to $66 million).  相似文献   

4.
The impact of asthma, exposure period, and filter condition downstream of the mixing box of air‐conditioning system on building occupants' perceptual response, work performance, and salivary α‐amylase secretion during exposures to ozone and its initiated chemistry products is studied. The experiments were conducted in a field environmental chamber (FEC) (240 m3) simulating an office environment. Experiments were conducted during periods when the air‐handling system operated with new or used pleated panel filters at constant recirculation (7/h) and ventilation (1/h) rates. Average ozone and secondary organic aerosols (ozone‐initiated chemistry products) measured during non‐asthmatic and asthmatic subjects' 3‐h exposures in the FEC were in the ranges approximately 20–37 ppb and approximately 1.6–3 μg/m3, respectively. Asthmatic subjects' perceived odor intensity and sensory (eye, nose, and throat) irritation ratings were generally lower than those of non‐asthmatic subjects, possibly explaining why asthmatic subjects accept perceived air quality more than non‐asthmatic subjects. However, asthmatic subjects' perceived physiological‐like symptom ratings (flu, chest tightness, and headache) and concentrations of secreted salivary α‐amylase were generally higher than those of non‐asthmatic subjects. Asthmatic subjects had significantly lower accuracy than non‐asthmatic subjects in a task that required higher concentration although they had higher work speed. Filter condition did not make any significant difference for subjects' responses.  相似文献   

5.
In order to investigate disastrous seismic resonant effect of resonant ground motions on tall building structures, a 1/40 scaled planar test model of a 56‐story core‐outrigger structure was tested on shaking table considering two types of ground motions, that is, non‐resonant and resonant ground motions. The non‐resonant ground motions were chosen from far‐field natural earthquake records, whereas the resonant ground motions were generated through scaling Fourier spectra of the non‐resonant ones in a target period region covering one of the first two natural periods of the test model. The test results showed that (a) with the same small peak ground acceleration of 0.07 g, the test model exhibited significant hysteretic behavior, residual displacement, and even overturning collapse under the resonant ground motions but behaved elastically under the non‐resonant ones; (b) the first‐period resonant ground motion caused extremely large displacements on the upper floors and large moments on the lower stories, whereas the second‐period resonant ground motion resulted in extremely large accelerations on the upper and middle floors; (c) the first‐period resonant ground motion was more probable to trigger overturning collapse of the core‐outrigger system after some exterior columns had reached their axial compression strength, even for those columns on the middle stories.  相似文献   

6.
This study measured air exchange rates, indoor concentrations of aldehydes and volatile organic compounds (VOCs), and radioactivity levels at 19 temporary houses in different temporary housing estate constructed in Minamisoma City following the Great East Japan Earthquake. The 19 surveyed houses represented all of the companies assigned to construct temporary houses in that Minamisoma City. Data were collected shortly after construction and before occupation, from August 2011 to January 2012. Mean air exchange rates in the temporary houses were 0.28/h, with no variation according to housing types and construction date. Mean indoor concentrations of formaldehyde, acetaldehyde, toluene, ethylbenzene, m/p‐xylene, o‐xylene, styrene, p‐dichlorobenzene, tetradecane, and total VOCs (TVOCs) were 29.2, 72.7, 14.6, 6.35, 3.05, 1.81, 7.29, 14.3, 8.32, and 901 μg/m3, respectively. The levels of acetaldehyde and TVOCs exceeded the indoor guideline (48 μg/m3) and interim target (400 μg/m3) in more than half of the 31 rooms tested. In addition to guideline chemicals, terpenes (α‐pinene and d‐limonene) and acetic esters (butyl acetate and ethyl acetate) were often detected in these houses. The indoor radiation levels measured by a Geiger–Müller tube (Mean: 0.22 μSv/h) were lower than those recorded outdoors (Mean: 0.42 μSv/h), although the shielding effect of the houses was less than for other types of buildings.  相似文献   

7.
Soils collected from the Gezira irrigation scheme in Sudan were incubated with five pesticides (pyrolan, α‐and β‐endosulphan, γ‐HCH and dieldrin), using three independent methods (incubation of microbial culture with soil and leachates, with carbon‐based growth media and with carbon‐free mineral salt agar). Endosulphan isomers were degraded by soil micro‐organisms to a much greater extent than pyrolan, dieldrin or γ‐HCH. When applied at low concentration (280 ppm), α‐endosulphan was broken down by both bacteria and fungi; whereas, β‐endosulphan was degraded mostly by bacteria and dieldrin was utilized by fungi. However, at high concentration (4000 ppm), γ‐HCH increased the growth of micro‐organisms (gram positive bacilli); but at this high concentration, the other pesticides inhibited all micro‐organisms in the Gezira soil.  相似文献   

8.
Indoor fine particles (FPs) are a combination of ambient particles that have infiltrated indoors, and particles that have been generated indoors from activities such as cooking. The objective of this paper was to estimate the infiltration factor (Finf) and the ambient/non‐ambient components of indoor FPs. To do this, continuous measurements were collected indoors and outdoors for seven consecutive days in 50 non‐smoking homes in Halifax, Nova Scotia in both summer and winter using DustTrak (TSI Inc) photometers. Additionally, indoor and outdoor gravimetric measurements were made for each 24‐h period in each home, using Harvard impactors (HI). A computerized algorithm was developed to remove (censor) peaks due to indoor sources. The censored indoor/outdoor ratio was then used to estimate daily Finfs and to determine the ambient and non‐ambient components of total indoor concentrations. Finf estimates in Halifax (daily summer median = 0.80; daily winter median = 0.55) were higher than have been reported in other parts of Canada. In both winter and summer, the majority of FP was of ambient origin (daily winter median = 59%; daily summer median = 84%). Predictors of the non‐ambient component included various cooking variables, combustion sources, relative humidity, and factors influencing ventilation. This work highlights the fact that regional factors can influence the contribution of ambient particles to indoor residential concentrations.  相似文献   

9.
Few measurements of exposure to secondhand smoke (SHS) in close proximity to a smoker are available. Recent health studies have demonstrated an association between acute (<2 h) exposures to high concentrations of SHS and increased risk of cardiovascular and respiratory disease. We performed 15 experiments inside naturally ventilated homes and 16 in outdoor locations, each with 2–4 non‐smokers sitting near a cigarette smoker. The smoker's and non‐smokers' real‐time exposures to PM2.5 from SHS were measured by using TSI SidePak monitors to sample their breathing zones. In 87% of the residential indoor experiments, the smoker received the highest average exposure to SHS, with PM2.5 concentrations ranging from 50–630 μg/m3. During the active smoking period, individual non‐smokers sitting within approximately 1 m of a smoker had average SHS exposures ranging from negligible up to >160 μg/m3 of PM2.5. The average incremental exposure of the non‐smokers was higher indoors (42 μg/m3, = 35) than outdoors (29 μg/m3, = 47), but the overall indoor and outdoor frequency distributions were similar. The 10‐s PM2.5 averages during the smoking periods showed great variability, with multiple high concentrations of short duration (microplumes) both indoors and outdoors.  相似文献   

10.
Boron is a vital micronutrient for the growth of plants and different organisms. However, boron may be toxic to living cells at high concentrations. Nevertheless, microorganisms can be grown in harsh conditions such as environments with higher boron concentrations. It is also known that boron‐tolerant microorganisms have significant biotechnological potentials. In this study, it is aimed to isolate microorganism from a boron containing place in K?rka, Eski?ehir using culture‐dependent methods. After extracting genomic DNAs, Amplified Ribosomal DNA Restriction Analysis (ARDRA) profiles were constructed with HaeIII, MspI, HinfI‐HpaII and AluI‐CfoI. Sequence analyses were performed by chain‐terminating method. Consensus sequences were completed and similarities were determined by RDP Release 11. According to ARDRA, 10 profiles and five different species such as Pseudomonas sp., Enterecoccus sp., Acinetobacter sp., Bacillus sp. and Halomonas sp. were identified.  相似文献   

11.
Indoor environmental quality (IEQ) has become an important component of green building certification schemes. While green buildings are expected to provide enhanced IEQ, higher occupant satisfaction, and less risks of occupant health when compared with non‐green buildings, the literature suggests inconsistent evidence due to diverse research design, small sample size, and weak statistical analysis. This study compared several outcomes pertinent to IEQ performance in green and non‐green office buildings in Singapore. Adopting a cross‐sectional study design, objective measurements were taken in eight green and six non‐green buildings, and satisfaction and acute health symptom risks of 367 occupants were obtained. Green buildings exhibited lower concentration of PM2.5, bacteria, and fungi and maintained temperature and humidity more consistently compared to non‐green counterparts. The mean ratings for satisfaction with temperature, humidity, lighting level, air quality, and indoor environment were higher in green buildings (with statistical significance P < 0.05). There was statistically significant reduction in risk of occupants having headache, unusual fatigue, and irritated skin in green buildings. Although matching of buildings and occupant characteristics, survey participation bias, and sampling duration (a 1‐week snapshot) of IEQ monitoring remain as limitations, this study offered positive association of green buildings with qualitatively and quantitatively measured performance of IEQ.  相似文献   

12.
Solid fuel burning cookstoves are a major source of household air pollution (HAP) and a significant environmental health risk in Sri Lanka. We report results of the first field study in Sri Lanka to include direct measurements of both real‐time indoor concentrations and personal exposures of fine particulate matter (PM2.5) in households using the two most common stove types in Sri Lanka. A purposive sample of 53 households was selected in the rural community of Kopiwatta in central Sri Lanka, roughly balanced for stove type (traditional or improved ‘Anagi’) and ventilation (chimney present or absent). At each household, 48‐h continuous real‐time measurements of indoor kitchen PM2.5 and personal (primary cook) PM2.5 concentrations were measured using the RTI MicroPEM? personal exposure monitor. Questionnaires were used to collect data related to household demographics, characteristics, and self‐reported health symptoms. All primary cooks were female and of an average age of 47 years, with 66% having completed primary education. Median income was slightly over half the national median monthly income. Use of Anagi stoves was positively associated with a higher education level of the primary cook (P = 0.026), although not associated with household income (P = 0.18). The MicroPEM monitors were well‐received by participants, and this study's valid data capture rate exceeded 97%. Participant wearing compliance during waking hours was on average 87.2% on Day 1 and 83.3% on Day 2. Periods of non‐compliance occurred solely during non‐cooking times. The measured median 48‐h average indoor PM2.5 concentration for households with Anagi stoves was 64 μg/m3 if a chimney was present and 181 μg/m3 if not. For households using traditional stoves, these values were 70 μg/m3 if a chimney was present and 371 μg/m3 if not. Overall, measured indoor PM2.5 concentrations ranged from a minimum of 33 μg/m3 to a maximum of 940 μg/m3, while personal exposure concentrations ranged from 34 to 522 μg/m3. Linear mixed effects modeling of the dependence of indoor concentrations on stove type and presence or absence of chimney showed a significant chimney effect (65% reduction; P < 0.001) and an almost significant stove effect (24% reduction; P = 0.054). Primary cooks in households without chimneys were exposed to substantially higher levels of HAP than those in households with chimneys, while exposures in households with traditional stoves were moderately higher than those with improved Anagi stoves. As expected, simultaneously measuring both indoor concentrations and personal exposure levels indicate significant exposure misclassification bias will likely result from the use of a stationary monitor as a proxy for personal exposure. While personal exposure monitoring is more complex and expensive than deploying simple stationary devices, the value an active personal PM monitor like the MicroPEM adds to an exposure study should be considered in future study designs.  相似文献   

13.
The two‐chambered microbial fuel cell (MFC) was designed and used for studying the efficiency of the real wastewater treatment from a non‐steroidal anti‐inflammatory pharmaceutical plant as well as from synthetic wastewater containing diclofenac sodium (DS). The removal of the contaminants was expressed regarding chemical oxygen demand (COD) removal, as measured by spectrophotometry experiments. Moreover, the effect of two different types of the cathode on current characteristics and COD removal was investigated. This research showed that the Pt‐coated Ti cathode could lead to higher efficiency of both power density and COD removal. In this case, the results indicated that the maximum power density (Pmax) was 20.5 and 6.5 W/m3 and the maximum COD removal was 93 and 78% for MFCs using real and synthetic wastewater, respectively.  相似文献   

14.
While household air pollution from biomass fuel combustion has been linked to cardiovascular disease, the effects on cardiac structure and function have not been well described. We sought to determine the association between biomass fuel smoke exposure and cardiac structure and function by transthoracic echocardiography. We identified a random sample of urban and rural residents living in the high‐altitude region of Puno, Peru. Daily biomass fuel use was self‐reported. Participants underwent transthoracic echocardiography. Multivariable linear regression was used to examine the relationship of biomass fuel use with echocardiographic measures of cardiac structure and function, adjusting for age, sex, height, body mass index, diabetes, physical activity, and tobacco use. One hundred and eighty‐seven participants (80 biomass fuel users and 107 non‐users) were included in this analysis (mean age 59 years, 58% women). After adjustment, daily exposure to biomass fuel smoke was associated with increased left ventricular internal diastolic diameter (P=.004), left atrial diameter (P=.03), left atrial area (four‐chamber) (P=.004) and (two‐chamber) (P=.03), septal E′ (P=.006), and lateral E′ (P=.04). Exposure to biomass fuel smoke was also associated with worse global longitudinal strain in the two‐chamber view (P=.01). Daily biomass fuel use was associated with increased left ventricular size and decreased left ventricular systolic function by global longitudinal strain.  相似文献   

15.
Exopolysaccharides (EPS) of microbial origin is a promising alternative to chemical flocculants due to their sustainability and eco‐friendly nature. In the present study, EPS produced by Bacillus cereus SK was studied and their flocculating activity was investigated. On incubation for 48 h, B. cereus SK produced 0.919 ± 0.022 g/L of EPS from a cell mass of 3.59 ± 0.06 g/L. The isolated EPS was identified as glycoprotein and chemical characterization by FTIR spectroscopic analysis suggested the presence of hydroxyl, amino and carboxyl groups. The kaolin clay flocculating activity of 83.4% was obtained on treatment with 12 mg/L of EPS. At 30% (v/v) of EPS 31.22 ± 4.71 mL/g of Sludge volume index (SVI) and 34.44 ± 1.51 mL/g of algal flocculation was observed. The EPS produced by B. cereus SK was non‐toxic and did not exert any adverse effect on Danio rerio even at a concentration of 800 mg/mL.  相似文献   

16.
Outdoor aerosols are transported indoors, where their component concentrations depend on aerosol size, physiochemical properties, indoor sources and losses, and cross‐environment gradients of temperature and relative humidity. We explored these dependencies by measuring real‐time outdoor and indoor non‐refractory, submicron (PM1) aerosol component mass concentrations in a mixed‐use laboratory space with an Aerodyne mini‐aerosol mass spectrometer (AMS) and black carbon (BC) with an aethalometer. The median indoor/outdoor (I/O) ratios were 0.60 for sulfate, 0.25 for nitrate, 0.52 for ammonium, 0.73 for organics, and 0.61 for BC. Positive matrix factorization (PMF) on organic aerosol data identified hydrocarbon‐like (HOA), cooking (COA), and oxygenated (OOA) factors. By assuming sulfate was nonvolatile, lost only by mechanical processes, and without indoor sources, the transformations of other components i due to partitioning changes or indoor sources were parameterized by normalizing their I/O ratios by sulfate's I/O ratio, that is, (I/O)i/SO4. Component‐specific behavior was quantified by regressions of (I/O)i/SO4 to outdoor‐to‐indoor temperature differences. Nitrate and HOA strongly and OOA weakly showed losses with increasing temperatures indoors vs. outdoors, and HOA likely had an indoor source. To our knowledge, this is the first reported deployment of an AMS to analyze real‐time indoor aerosol composition and outdoor‐to‐indoor transformation.  相似文献   

17.
Chromium can have detrimental effects on most organisms, including humans. The present study focused on the effect of treating chromium‐bearing, organic‐rich wastewater on constructed wetland performance. Eight laboratory‐scale systems were used to study organic matter and chromium removals, with three features tested in duplicate: media with proven chromium sorption capacity, vegetation presence and intermittent influent loading. A set of two wetlands acted as the base design. Average BOD5 and chromium removal rates were 13.4 g/m2 day and 135 mg Cr/m2 day, respectively. From an influent chromium concentration of 5 mg/L, <0.5 mg/L could be detected at the outlet during the study in all systems. Chromium removal efficiencies were statistically different for all systems (P<0.01), except when comparing the base design against the intermittent feed systems (P>0.05). Overall treatment performance of all systems was remarkably good in spite of significant chromium content and salinity.  相似文献   

18.
Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non‐toxigenic. A preliminary analysis of VOCs was conducted using solid‐phase microextraction‐gas chromatography‐mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1‐octen‐3‐ol, 3‐octanone, 3‐octanol, 2‐octen‐1‐ol, and 2‐nonanone; while the less toxic molds produced more 3‐methyl‐1‐butanol and 2‐methyl‐1‐propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic.  相似文献   

19.
Real‐time bioaerosol monitoring is possible with fluorescence based instruments. This study provides information on major factors that can affect the fluorescence properties of airborne fungal spores. Two fluorescence‐based bioaerosol detectors, BioScout, and ultraviolet aerodynamic particle sizer (UVAPS), were used to study fluorescent particle fractions (FPFs) of released spores of three fungal species (Aspergillus versicolor, Cladosporium cladosporioides, and Penicillium brevicompactum). Two culture media (agar and gypsum board), three ages of the culture (one week, one month, and four months), and three aerosolization air velocities (5, 15, and 27 m/s) were tested. The results showed that the FPF values for spores released from gypsum were typically lower than for those released from agar indicating that poor nutrient substrate produces spores with lower amounts of fluorescent compounds. The results also showed higher FPF values with lower air velocities in aerosolization. This indicates that easily released fully developed spores have more fluorescent compounds compared to forcibly extracted non‐matured spores. The FPFs typically were lower with older samples. The FPF results between the two instruments were similar, except with four‐month‐old samples. The results can be utilized in field measurements of fungal spores to estimate actual concentrations and compare different instruments with fluorescence‐based devices as well as in instrument calibration and testing in laboratory conditions.  相似文献   

20.
Indoor smoke exposure may affect cardiovascular disease (CVD) risk via lung‐mediated inflammation, oxidative stress, and endothelial inflammation. We sought to explore the association between indoor smoke exposure from burning biomass fuels and a selected group of markers for endothelial inflammation. We compared serum concentrations of amyloid A protein, E‐selectin, soluble intercellular adhesion molecule 1 (ICAM‐1) and VCAM‐1, von Willebrand factor (vWF), and high‐sensitivity C‐reactive protein (hs‐CRP) in 228 biomass‐exposed vs. 228 non‐exposed participants living in Puno, Peru. Average age was 56 years (s.d. = 13), average BMI was 26.5 kg/m2 (s.d. = 4.4), 48% were male, 59.4% completed high school, and 2% reported a physician diagnosis of CVD. In unadjusted analysis, serum levels of soluble ICAM‐1 (330 vs. 302 ng/ml; P < 0.001), soluble VCAM‐1 (403 vs. 362 ng/ml; P < 0.001), and E‐selectin (54.2 vs. 52.7 ng/ml; P = 0.05) were increased in biomass‐exposed vs. non‐exposed participants, respectively, whereas serum levels of vWF (1148 vs. 1311 mU/ml; P < 0.001) and hs‐CRP (2.56 vs. 3.12 mg/l; P < 0.001) were decreased, respectively. In adjusted analyses, chronic exposure to biomass fuels remained positively associated with serum levels of soluble ICAM‐1 (P = 0.03) and VCAM‐1 (P = 0.05) and E‐selectin (P = 0.05), and remained negatively associated with serum levels of vWF (P = 0.02) and hs‐CRP (P < 0.001). Daily exposure to biomass fuel smoke was associated with important differences in specific biomarkers of endothelial inflammation and may help explain accelerated atherosclerosis among those who are chronically exposed.  相似文献   

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