Abstract Flour beetles of the genus Tribolium Macleay (Coleoptera: Tenebrionidae) are important stored product pests in China and worldwide. They are often found or are intercepted in grain depots, flour mills, and entry-exit ports, etc. Traditionally, Tribolium species are identified according to the morphological characteristics of the adult. However, it is almost impossible to rapidly identify adult fragments and non-adult stages based on external morphological characteristics. Molecular techniques for the rapid and accurate identification of Tribolium species are required, particularly for pest monitoring and the quarantine of stored products pests. Here, we establish DNA barcoding, species-specific PCR, and real-time PCR techniques for the identification of six stored-product pest Tribolium species including T. castaneum , T. confusum , T. destructor , T. madens , T. freemani and T. brevicornis . We detected the mitochondrial DNA cytochrome oxidase subunit I (COI) barcodes for Tribolium from 18 geographic populations and 101 individuals, built a Tribolium DNA barcode library, and designed species-specific primers and TaqMan probes for the above six Tribolium species. The three techniques were applied to identify Tribolium collected from stored samples and samples captured from quarantine ports. The results demonstrated that three techniques were all able to identify the six species of Tribolium both rapidly and accurately.
Abstract Exposure to fine particulate matter (PM 2.5 ) is linked to lung cancer incidence and mortality. However, the impact of PM 2.5 exposure on lung cancer patients after lobectomy, which remains the primary treatment for early-stage lung cancer, is unknown. Therefore, we investigated the correlation between PM 2.5 exposure and the survival of lung cancer patients after lobectomy. This study included 3,327 patients with lung cancer who underwent lobectomy procedures. We converted residential addresses into coordinates and estimated individual patients' daily PM 2.5 and O 3 exposure levels. A Cox multivariate regression model was used to analyze the specific monthly association between PM 2.5 exposure and lung cancer survival. Every 10 μg/m 3 increase in monthly PM 2.5 concentration in the first and second months after lobectomy increased the risk of death (hazard ratio [HR]: 1.043, 95% confidence interval [CI]: 1.019–1.067 and HR: 1.036, 95% CI: 1.013–1.060, respectively). Non-smokers, younger patients, and patients with longer hospitalization durations had worse survival rates when exposed to greater concentrations of PM 2.5 . High postoperative PM 2.5 exposure immediately after lobectomy reduced the survival of patients with lung cancer. Patients living in areas with high PM 2.5 should be offered the opportunity to transfer to areas with better air quality after undergoing lobectomies, to prolong their survival times.
A large amount of mixed dust exists in grain, which can easily stimulate the respiratory system and cause diseases. This study explored contamination levels and health effects of this grain dust. A total of 616 dust samples from different stages and types of grain were collected in China—in Hefei (Anhui), Shenzhen (Guangdong), Chengdu (Sichuan), Changchun (Jilin), and Shunyi (Beijing)—and analyzed using the filter membrane method and a laser particle size analyzer. A probabilistic risk assessment model was developed to explore the health effects of grain dust on workers in the grain storage industry based on the United States Environmental Protection Agency risk assessment model and the Monte Carlo simulation method. Sensitivity analysis methods were used to analyze the various exposure parameters and influencing factors that affect the health risk assessment results. This assessment model was applied to translate health risks into disability-adjusted life years (DALY). The results revealed that the concentration of dust ranged from 25 to 70 mg/m3, which followed normal distribution and the proportion of dust with a particle size of less than 10 μm exceeded 10%. Workers in the transporting stage were exposed to the largest health risk, which followed a lognormal distribution. The average health risks for workers in the entering and exiting zones were slightly below 2.5 × 10−5. The sensitivity analysis indicated that average time, exposure duration, inhalation rate, and dust concentration made great contributions to dust health risk. Workers in the grain storage and transportation stage had the health damage, and the average DALY exceeded 0.4 years.
Tribolium castaneum (Herbst) is an important pest of stored grain, and benzoquinones secreted by this pest are harmful to humans. T. castaneum has developed strong resistance to fumigants, and an ecofriendly alternative for managing T. castaneum is urgently needed. 1-Octen-3-ol is a major volatile compound present in many mushrooms and fungi. In the current study, the direct toxicity and sublethal and transgenerational effects of 1-octen-3-ol on T. castaneum were investigated. Our results showed that 1-octen-3-ol had strong insecticidal activity against all developmental stages of T. castaneum and repelled T. castaneum adults. 1-Octen-3-ol showed negative effects on the development and reproduction of parental T. castaneum and the subsequent generation: LC30 and LC50 treatments significantly decreased the pupa and adult weights, pupation and emergence rates and fecundity of the parental generation. In addition, LC50 treatment shortened the larval and pupal periods. In the unexposed progeny (F1) of 1-octen-3-ol-exposed parents, decreased survival and pupation rates as well as reduced pupa and adult weights were observed under LC30 and LC50 treatments. In addition, a model food-system experiment showed that 1-octen-3-ol at 98 μL/L exhibited an efficacy of 100% after 7 days of fumigation and completely eliminated T. castaneum offspring. Although a higher concentration of 1-octen-3-ol was needed to achieve an efficacy equal to that of the positive control, dichlorvos (DDVP), 1-octen-3-ol promoted the seedling growth of wheat seeds, suggesting that the concentration used was not only acceptable but also beneficial for wheat seeds. Overall, 1-octen-3-ol seems to be a promising candidate for use as a fumigant and repellent against T. castaneum as well as a seed protectant.
Numerous studies have found associations between ambient fine particulate matter (PM2.5) and increased mortality risk. However, little evidence is available on associations between PM2.5 and years of life lost (YLL). We aimed to estimate the YLL due to chronic obstructive pulmonary disease (COPD) mortality related to ambient PM2.5 exposure. A time-series study was conducted based on the data on air pollutants, meteorological conditions and 18,472 registered COPD deaths in Ningbo, China, 2011–2015. The effects of PM2.5 on YLL and daily death of COPD were estimated, after controlling long term trend, meteorological index and other confounders. The impact of PM2.5 on YLL due to COPD lasted for 5 days (lag 0–4). Per 10 μg/m3 increase in PM2.5 was associated with 0.91 (95%CI: 0.16, 1.66) years increase in YLL. The excess YLL of COPD mortality were 8206 years, and 0.38 day per person in Ningbo from 2011 to 2015. The exposure-response curve of PM2.5 and YLL due to COPD showed a non-linear pattern, with relatively steep at low levels and flattened out at higher exposures.. Furthermore, the effects were significantly higher in the elderly than those in the younger. Our findings explored burden of PM2.5 on YLL due to COPD and highlight the importance and urgency of ambient PM2.5 pollution control and protection of the vulnerable populations.
Whether and to what extent the impact of exposure to various polychlorinated biphenyls (PCBs) congeners on diabetes, as well as the important contributors, have remained unclear.
In response to global climate change, future precipitation changes are expected to profoundly influence soil respiration in arid and semiarid areas. However, few studies focus on CO2 emissions from soils undergoing precipitation changes in semiarid mountain shrublands in winter. A precipitation-manipulation experiment with three levels of precipitation (30% decreased precipitation (DP), ambient precipitation (AP), and 30% increased precipitation (IP)) was performed to examine the effects of variable precipitation on soil respiration (SR) and wintertime contributions to annual SR emissions in Vitex negundo var. heterophylla shrub ecosystems located on the Middle Taihang Mountain in Hebei Province, northern China. The results showed that the average annual SR rates and winter SR rates ranged from 1.37 to 1.67 μmol m−2 s−1 and 0.42 to 0.59 μmol m−2 s−1 among the different precipitation treatments. The model based on soil moisture better represented the soil-respiration rates, suggesting that the variable precipitation extended the water’s limitation of the soil’s CO2 emissions. The cumulative annual soil CO2 emissions were 523, 578, and 634 g C m−2 in response to the DP, AP, and IP treatments, respectively. The ratio of the soil CO2 emissions in winter to the annual CO2 emissions varied from 7.6 to 8.8% in response to the different precipitation treatments. Therefore, ignoring the soil CO2 emissions in winter leads to the underestimation of the carbon losses in semiarid shrublands. Our results highlight that variable precipitation significantly influences soil-respiration rates, and soil CO2 emissions in winter must not be ignored when predicting the future feedback between SR and climate change in semiarid regions.
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