[An analysis of the status quo of ground-level ozone pollution research].

Objective: To analyze the research status of ground-level ozone pollution, explore research trends and hot spots, and provide references for future research on air pollution. Methods: Papers on ground-level ozone pollution research published before December 31, 2019 had been retrieved in SCI-E database of the "Web of Science Core Collection" in January 2020. The retrieval strategies were set as follows: TS= ( ("Tropospheric Ozone" OR "Low Level Ozone" OR "Ground Level Ozone") AND ("Air pollution*" OR "Air quality") ) . The survey included 2084 articles. By using bibliometric research and visual analysis tools, the research status of global ground-level ozone pollution was revealed from the aspects of time, discipline, journal, financing, institution, country and key words. Results: Cumulative publications increased in a cubic function of y=0.05x(3)+0.80x(2)+0.74x+4.55 (R(2)=0.999, P<0.01) . The most studied subject was Environmental sciences ecology (1401 articles, 67.23%) . Atmospheric Environment was the journal with the most articles (332 articles, 15.93%) . The United States was the country with the most publications (44.67%, 931/2084) , while China ranked second (17.13%, 357/2084) . 80.39% (287/357) of Chinese papers had funding information. Among the top 10 research institutions, 7 and 2 were affiliated to the United States and China respectively. Source apportionment and human health were high frequency keywords that had appeared in the last 5 years. Conclusion: The research on ground-level ozone pollution is in a good period of development. The United States has a leading position in this area, and China has a good prospect in this field. Pollution source apportionment and human health effects are new research directions.

[Investigation on the health status of workers exposed to benzene in one province].

Objective: To explore the health status of occupational benzene exposure workers, and to provide a scientific basis for the development of reasonable health monitoring and effective protective measures. Methods: In March 2019, the occupational health surveillance data were collected including blood pressure, electrocardiogram, blood routine, urine routine, liver function, etc of 7810 benzene contact workers in 150 enterprises in Jiangxi Province in 2017, to analyze and assess their health status. Results: Among the 7810 benzene workers, there were 5451 males and 2359 females; the average age was (40.5±9.9) years; and the median benzene working age was 3.5 years. The detection rate of hypertension was 17.0% (734/4317) , the abnormal rate of urine routine was 15.7% (1227/7810) , the abnormal rate of liver function was 8.6% (356/4147) , and the abnormal rate of electrocardiogram was 12.3%(963/7810). The detection rates of low count number of leukocytes, platelets, neutrophils and occupational contraindications were 4.6%(360/7810) , 1.4%(108/7810) , 4.2%(330/7810) and 1.4%(110/7810) , respectively. The detection rates of low count number of leukocytes, platelets and neutrophils in female were all higher than those in male (P<0.05). The detection rates of low count number of platelets, neutropenia and occupational contraindications increased with age and working age (P<0.05 ). There were significant differences in the detection rates of low count number of leukocytes, platelets, neutrophils and occupational contraindications among benzene workers in different economic types (P<0.05) , and the highest among foreign companies, followed by private enterprise. There were statistically significant differences in the detection rates of low count number of platelets, neutrophils and occupational contraindications in benzene workers of different enterprise sizes (P<0.05) , and the highest was found in micro enterprises, followed by small enterprises. Conclusion: In 2017, the occupational health status of workers exposed to benzene in Jiangxi province is not optimistic. It is necessary to strengthen the occupational health supervision of small and micro-sized enterprises, foreign enterprises and private enterprises, take the initiative to improve health surveillance, and effectively protect the physical and mental health of workers.

Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions / O investimento de tiro aumentado faz plantas invasivas exposição de vantagens de crescimento em altas condições de nitrógeno

Abstract Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

Resumo As alterações de recursos geralmente promovem invasões de plantas, suscitando preocupações quanto às conseqüências potenciais da deposição de nitrogênio (N); No entanto, não está claro se os invasores se beneficiarão da deposição de N mais do que com os nativos. O crescimento é um dos traços inerentes mais fundamentais das plantas e, portanto, os bons invasores podem ter vantagens de crescimento superiores em resposta a alterações de recursos. Comparamos o crescimento e a alocação entre plantas invasivas e nativas em diferentes regimes de N, incluindo controles (concentrações ambientais de N). Descobrimos que as plantas invasivas sempre cresceram muito mais do que as plantas nativas em diferentes condições de N, independentemente das análises baseadas em crescimento ou filogenia, e que o primeiro atribuiu mais biomassa aos rebentos do que o segundo. Embora N aumentou o crescimento de plantas invasivas, esse aumento não aumentou com o aumento da adição de N. Através das espécies invasivas e nativas, as mudanças na alocação da biomassa do extrato foram correlacionadas positivamente com as mudanças na biomassa da planta inteira; e a inclinação desse relacionamento foi maior em plantas invasivas do que plantas nativas. Essas descobertas sugerem que o aumento do investimento em lançamentos faz com que as plantas invasivas mantenham uma vantagem de crescimento em altas condições de N em relação aos nativos, e também destacar que a futura deposição de N pode aumentar os riscos de invasões de plantas.

Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions.

Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

Two approaches for addressing electrochemical electrode arrays with reduced external connections.

Although patterning hundreds or thousands of electrochemical electrodes on lab-on-a-chip devices is straightforward and cost-effective using photolithography, easily making connections between hundreds of electrodes and external amplifiers remains a bottleneck. Here we describe two electrode addressing approaches using multiple fluid compartments that can potentially reduce the number of external connections by ~100-fold. The first approach enables all compartments on the device to be filled with solution at the same time, and then each fluid compartment is sequentially electrically activated to make the measurements. The second approach achieves lower measurement noise by sequentially filling recording chambers with solution. We propose an equivalent circuit to explain measurement noise in these recording configurations and demonstrate application of the approaches to measure quantal exocytosis from individual cells. A principle advantage of using these approaches is that they reduce the fraction of the microchip area that needs to be dedicated to making external connections and therefore reduces the cost per working electrode.

The dynamic change of circulating tumour cells in patients with operable breast cancer before and after chemotherapy based on a multimarker QPCR platform.

BACKGROUND: The possible presence of early tumour dissemination is the rationale behind the use of systemic adjuvant chemotherapy in patients with operable breast cancer. Circulating tumour cells (CTC) in peripheral blood may represent the possible presence of early tumour dissemination. However, relatively few studies were designed to investigate the relationship between the change of CTC status and the efficacy of adjuvant chemotherapy in operable breast cancer patients. METHODS: In a prospective study, we established a multimarker real-time quantitative PCR platform to detect CTC in peripheral blood of breast cancer patients. By using this platform, we detected CTC in peripheral blood of 94 operable breast cancer patients. Control group consisted of 20 patients with benign breast disease and 20 healthy volunteers. For 72 patients who underwent systemic adjuvant chemotherapy, the dynamic CTC status at three different time points (1 day before initiation of chemotherapy, 1 week after three cycles of chemotherapy and 1 week after all cycles of chemotherapy) was observed. RESULTS: Circulating tumour cells were detected in 56% (53 out of 94) of patients with operable breast cancer. The specificity was 95%. Seventy-two patients who received systemic adjuvant chemotherapy were followed up. After three cycles of chemotherapy, 47% (18 out of 38) of patients who were CTC-positive before chemotherapy changed into negative status. In addition, another 5% (2 out of 38) of patients had changed into negative status after all cycles of chemotherapy. CONCLUSION: Systemic adjuvant chemotherapy had a significant impact on CTC status, and this effect could be observed after three cycles of chemotherapy. Circulating tumour cells detection had the potential to be used to evaluate the efficacy of systemic adjuvant chemotherapy immediately after the chemotherapy was finished in operable breast cancer patients.

[Role of afferent C fibers in electroacupuncture of "zusanli" point in activating nucleus raphe magnus].

The purpose of the present work is to study whether the analgesia of "Zusanli" EA was mainly produced by its noxious effect. The antidromic C waves on N. peroneus communis innervating the area of "Zusanli" point were recorded. When "Zusanli" point was stimulated by trains of stimuli, the amplitude of the antidromic C wave was obviously decreased due to collision with the orthodromic stimulation. It was suggested that EA of "Zusanli" could excite some C fibers. It was observed that when the stimulation intensity reached the threshold of C fiber, the NRM neurons were obviously activated, and when it reached or exceeded the intensity for producing the maximal C wave, the NRM neurons were highly activated. Therefore, EA analgesia is probably produced mainly by its noxious stimulus component, especially carried by C fibers, via a negative feedback mechanism in modulating pain.