Interactions of zinc and cadmium toxicity in their effects on growth and in antioxidative systems in tomato plants （Solanum lycopersicum）

The interaction between zinc and cadmium was investigated in tomato plants (Solanum lycopersicum). Ten-day-old seedlings were treated with 10 mol/L CdCl2 associated to di erent concentrations of ZnCl2 (10, 50, 100, and 150 mol/L). Zn supply clearly reduced Cd accumulation in leaves and simultaneously increased Zn concentration. Cd induced oxidative stress in leaves as indicated by an increase in thiobarbituric acid-reactive substances (TBARS) level and chlorophyll breakdown. Furthermore, compared with control, Cdtreated plants had significantly higher activities of superoxide dismutase (SOD, EC 1.15.1.1), whereas, catalase (CAT, EC 1.111.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase (GR, EC 1.6.4.2) activities were significantly suppressed by Cd addition. Zn supplementation, at low level, restored and enhanced the functional activity of these enzymes (SOD, CAT, APX and GR) as compared to Cd-alone-treated plants. The beneficial e ect of adequate Zn level on Cd toxicity was confirmed by a significant decrease in TBARS level and restoration of chlorophyll content. However, when Zn was added at high level in combination with Cd there was an accumulation of oxidative stress, which was higher than that for Cd or excess Zn alone treatments. These results suggested that higher Zn concentrations and Cd are synergistic in their e ect on plant growth parameters and oxidative stress.     

Film mulching reduces antibiotic resistance genes in the phyllosphere of lettuce

Phyllosphere is an important reservoir of antibiotic resistance genes(ARGs), but the transfer mechanism of ARGs from soil and air to phyllosphere remains unclear. This study demonstrated that soil-air-phyllosphere was the dominant ARG transfer pathway, and blocking it by film mulching can reduce typical phyllosphere ARGs in lettuce by 80.7%-98.7%(89.5% on average). To further eliminate phyllosphere ARGs in lettuce grown with film mulching, the internal soil-endosphere-phyllosphere transfer pathw...     

Fertility signaling in queens of a North American ant

In most species of advanced eusocial insects, the partitioning of reproduction between nestmates is thought to be regulated by means of primer pheromones or other chemical cues, which presumably influence the behavior of co-queens and workers such that they maximize their own inclusive fitness. Here we show that in multi-queen colonies of the Nearctic ant, Leptothorax sp. A, physical dominance in concert with chemical cues, which signal the ovarian development of a queen, are used to control reproduction of competing queens and to influence worker behavior. The analysis of ranks obtained during two fighting periods in the annual colony cycle revealed a strong link between individual aggressiveness of a queen and her fertility. During the adoption of newly mated queens in autumn, the resident, egg-laying α-queen was more likely to start aggression first and keep her high rank position compared to the fighting period after hibernation. We suggest that this is proximately caused by the α-queen having much stronger developed ovaries in autumn than the young queens, whereas after hibernation, the ovaries of all queens are similarly inactive. Interactions during the first weeks after the end of hibernation and intrinsic, individual differences in aggressiveness appear to be crucial for the dominance rank achieved later. Queens which were allowed to become fertile when their nestmate queens still were kept under prolonged hibernation, were immediately socially dominant over the latter when all queens were reunited, though no aggression occurred. In another experiment, queen antagonism was prevented by spatial separation in different parts of the same nest and all queens began to lay eggs. Workers stayed preferentially with queens with high actual fecundity rather than with those which had had high social status before separation. This and further evidence suggest that ovarian status is communicated, most likely by a chemical cue perceived by co-queens and workers, affects the direction of their aggressive behavior, and allows them to discriminate among queens. Received: 5 May 1998 / Accepted after revision: 29 August 1998     

Facilitating biodiversity conservation through partnerships to achieve transformative outcomes

Conservation biology is a mission-driven discipline that must navigate a new relationship between conservation and science. Because conservation is a social and political as well as an ecological project, conservation biologists must practice interdisciplinarity and collaboration. In a comparative study of 7 cases (Jaguars in the Chaco, Grevy's zebra in Kenya, Beekeeping in Tanzania, Andean cats in Argentina, Jaguars in Mexico, Lobster fishing, and Black bears in Mexico), we examined motivations for collaboration in conservation, who can collaborate in conservation, and how conservation professionals can work well together. In 5 case studies, successful conservation outcomes were prioritized over livelihood benefits. In the other 2 cases, livelihoods were prioritized. All case studies employed participatory approaches. There were multiple external actors, including local and Indigenous communities, nongovernmental organizations, agencies, regional and national governments, and international organizations, which enhanced conservation and wider sustainability outcomes. Key collaboration aspects considered across the case studies were time (mismatch between relationship building and project schedules), trust required for meaningful partnerships, tools employed, and transformative potential for people, nature, and the discipline of conservation biology. We developed guidelines for successful collaboration, including long-term commitment, knowledge integration, multiscalar and plural approaches, cultivation of trust, appropriate engagement, evaluation, supporting students, and efforts for transformation.     

A roadmap for ladybird conservation and recovery

Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.     

A systematic review of snake translocations to identify potential tactics for reducing postrelease effects

Advancements in the field of reintroduction biology are needed, but understanding of how to effectively conduct translocations, particularly with snakes, is lacking. We conducted a systematic review of snake translocation studies to identify potential tactics for reducing postrelease effects. We included studies on intentional, human-mediated, wild–wild, or captive–wild translocations to any location, regardless of motive or number of snakes translocated. Only studies that presented results for at least 1 of 4 outcomes (movement behavior, site fidelity, survival, or population establishment) were included. We systematically searched 4 databases for published studies and used 5 methods to search the gray literature. Our search and screening criteria yielded 121 data sources, representing 130 translocation cases. We quantified the association between 15 translocation tactics and short-term translocation outcomes by calculating odds ratios and used forest plots to display results. Snake translocations involved 47 species (from mainly 2 families), and most were motivated by research, were monitored for at least 6 months, occurred in North America, and took place from the 1990s onward. The odds of a positive snake translocation outcome were highest with release of captive reared or juvenile snakes, release of social groups together, delayed release, provision of environmental enrichment or social housing before release, or minimization of distance translocated. The odds of a positive outcome were lowest when snakes were released early in their active season. Our results do not demonstrate causation, but outcomes of snake translocation were associated with 8 tactics (4 of which were strongly correlated). In addition to targeted comparative studies, we recommend practitioners consider the possible influence of these tactics when planning snake translocations.     

京津冀区域PM2.5中碳组分污染特征研究

为了解京津冀区域PM_(2.5)中碳组分污染特征,于2015年7月和10月及2016年1月和4月在北京、天津、保定、石家庄、沧州5个城市同步采集PM_(2.5)样品,采用热/光分析法分析样品中有机碳(OC)和元素碳(EC),使用OC/EC最小比值法估算二次有机碳(SOC).结果表明:京津冀区域主要城市OC、EC和SOC的年均浓度分别为12.9~28.5、4.1~7.9和3.3~10.4μg·m~(-3),OC/EC和SOC/OC的比值分别为2.4~3.0和0.26~0.32.OC和EC的浓度呈现保定石家庄沧州天津北京的空间分布特点和夏季春季秋季冬季的季节变化特点.OC/EC的比值及OC和EC的相关性在夏季最低,冬季最高,这可能与京津冀区域冬季采暖燃煤有关,冬季不利的气象条件也加剧了碳质气溶胶污染.冬季较高的SOC浓度主要与低温、气态前体物的增加以及频繁出现的逆温、小风和混合层高度降低等不利气象条件有关.京津冀区域碳质气溶胶的污染特征具有空间相似性.     

膜法富氧助燃技术在节能和环保中的应用

主要介绍了该高新技术在玻璃窑、注汽炉、加热炉、热媒炉、燃煤炉、燃油及燃气炉等方面的典型应用,一般均具有显著的经济效益和社会效益,不但显著节能、增产,而且改善燃烧效率,延长炉龄,环保达标,通常几个月就能收回全部投资。     

Heat illness among high school athletes--United States, 2005-2009

Introduction

Heat illness is a leading cause of death and disability among U.S. high school athletes.

Methods

To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.

Results

During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.

Conclusions

Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.

Impact of industry

By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths.     

基于DHGF算法和三角模糊数的装备研制风险评价

针对风险管理方法难以对装备研制风险进行有效评价的问题,提出基于DHGF算法和三角模糊数的装备研制风险评价方法。运用德尔菲法建立装备研制风险的综合评价指标体系。基于三角模糊数和层次分析法(AHP)计算评价指标的权重。利用灰色系统理论确定评价灰类,计算灰色评价系数,得出灰色评价权向量和权矩阵。形成综合评判矩阵,进行模糊运算,求得综合评价结果。算例表明,该方法可有效用于装备研制风险的评价。