The role of soil humic and fulvic acid in the sorption of endosulfan (alpha and beta)

The sorption behaviour of alpha- and beta-endosulfan in soil organic matter was investigated using standard soil humic acid (HA) and soil fulvic acid (FA) with a modified solubility enhancement method and a dialysis bag technique. For HA, all the experiments were conducted at an ionic strength of 0.001 mol/L, in both the presence and absence of calcium and at an ionic strength of 0.01 mol/L. For FA, the experiments were conducted at two ionic strengths: 0.001 mol/L (with calcium) and 0.01 mol/L. This study is the first to describe the striking differences in the sorption behaviours of the two stereoisomers of endosulfan in HA and in FA. The sorption coefficients of alpha-endosulfan in HA and FA were significantly higher than those of beta-endosulfan. Beta-endosulfan has comparable sorption coefficients (1.5–5.4 L/g) in HA and in FA. Ionic strength and the presence of calcium have no significant effect on the sorption of beta-endosulfan in HA. However, calcium can significantly (p=0.01) enhance the solubility of alpha-endosulfan in HA. Changes in ionic strength by one order of magnitude also affect the solubility of alpha-endosulfan in HA. The sorption coefficients of alpha-endosulfan in HA (10–36 L/g) were greater than those in FA (9–14 L/g). The chirality of the alpha-isomer was hypothesised to be the primary reason behind its higher sorption in soil organic matter relative to the beta-isomer. In the presence of dissolved HA and FA found in natural soil environments, solubility of endosulfan can be increased by five times than the aqueous solubility of endosulfan without HA and FA.     

东平湖底泥重金属污染及其对摇蚊分布的影响

东平湖是南水北调东线的重要调蓄湖,其水环境状况对输水安全具有重要意义.为分析与评价东平湖底泥重金属污染状况及其与摇蚊分布关系,采集30个东平湖底泥样品,分别测试和鉴定其中的元素含量和摇蚊亚化石种属.运用地积累指数和生态危害指数法对东平湖底泥重金属污染进行分析评价,发现Cu、Pb、Zn、Ni是主要污染物,但污染程度相对较低,整体为轻度—中度污染水平,潜在生态危害性为轻微水平,且其污染及危害性均呈现出由湖区东南向西北逐渐降低的空间分布特征.其中,Cu污染最为严重,部分地区达到强污染水平.东平湖底泥共鉴定出41个摇蚊属种,主要优势种由Stempellinella-Zavrelia(30.88%)、Propsilocerus akamusi-type(26.79%)、Paratanytarsus(10.34%)、Cricotopus sylvestris-type(7.52%)和Hydrobaenus conformis-type(5.19%)组成.Stempellinella-Zavrelia和Propsilocerus akamusi-type是东平湖的绝对优势种,合占全湖的57.67%,且几乎呈全湖性分布.摇蚊RDA分析显示第一轴特征值为0.073,摇蚊种属与环境的相关关系达到了58.4%.RDA结果表明影响摇蚊组成分布的显著因子是Mn,并解释了7.3%的摇蚊变率.摇蚊属种Stempellinella-Zavrelia、Propsilocerus akamusi-type、Paratanytarsus、Hydrobaenus conformis-type等分布在Mn污染较小的区域.Pearson相关分析进一步表明东平湖底泥不同摇蚊种属对重金属Mn污染的响应存在显著差异.总体来看,底泥重金属对东平湖摇蚊组成和分布有显著影响,但不同金属对其影响存在差异.     

Benthic vegetation,chlorophyllα and physical-chemical variables in a protected zone of a Mediterranean coastal lagoon (Lesina,Italy)

Phytoplankton and benthic vegetation biomass undergoes spatial-temporal changes in relation to their life cycle, but also to meteorological conditions, physical-chemical variables, organic input and internal dynamism. The main aim of this work was to observe the effect of all environmental variables on the vegetative dynamic process in a protected zone of a Mediterranean costal lagoon (Lesina lagoon, SE Italy). Seven samplings were performed from 2010 to 2012 at 30 sites for nutrient and chlorophyll analyses, while TOC measurements and wet biomass evaluation were performed at 10 sites. Temperature, salinity and oxygen saturation were also measured by multiparametric probe and a visual census for vegetation was performed. Sites close to freshwater inflow were characterized by lower temperature and salinity, and high nitrate, with maxima of 191.05 μM in May 2010 and more than 250 μM in October 2010. Silicates drastically decreased from May 2010 (87.57 μM) to July 2010 (6.15 μM) and increased again in October (74.99 μM). Chl a concentrations were not on average higher than 6 mg m^?3, but peaks of 20 mg m^?3 were observed during May 2011 and May 2012. Benthic vegetation wet biomass collected in 2010 was approximately twice that collected in 2012, with a maximum of 27,554 g m^?2 and a dominance of macroalgae (70 % in May 2010 and 40 % in August 2010). During period 2010, a simultaneous and drastic decreasing of both mean values of wet biomass and chl a was observed from May to October 2010. During period 2012 a shift of vegetation biomass was shown from May (phytoplankton prevalence) to August 2012, with angiosperm prevalence (more than 30 %).     

Dynamic real-time risk analytics of uncontrollable states in complex internet of things systems: cyber risk at the edge

The Internet of Things (IoT) triggers new types of cyber risks. Therefore, the integration of new IoT devices and services requires a self-assessment of IoT cyber security posture. By security posture this article refers to the cybersecurity strength of an organisation to predict, prevent and respond to cyberthreats. At present, there is a gap in the state of the art, because there are no self-assessment methods for quantifying IoT cyber risk posture. To address this gap, an empirical analysis is performed of 12 cyber risk assessment approaches. The results and the main findings from the analysis is presented as the current and a target risk state for IoT systems, followed by conclusions and recommendations on a transformation roadmap, describing how IoT systems can achieve the target state with a new goal-oriented dependency model. By target state, we refer to the cyber security target that matches the generic security requirements of an organisation. The research paper studies and adapts four alternatives for IoT risk assessment and identifies the goal-oriented dependency modelling as a dominant approach among the risk assessment models studied. The new goal-oriented dependency model in this article enables the assessment of uncontrollable risk states in complex IoT systems and can be used for a quantitative self-assessment of IoT cyber risk posture.

     

Stakeholder perspectives on the value proposition of enterprise-level natural capital accounting for three primary industries

Environment Systems and Decisions - Globally we are experiencing a decline in aggregate natural capital. Many primary industries and enterprises are highly dependent on renewable and non-renewable...     

Effect of excess fluoride ingestion on human thyroid function in Gaya region,Bihar, India

Fluoride (F) is mainly ingested through drinking water and food. In addition to producing dental and skeletal fluorosis, excess fluoride may affect the functioning of many organs including the thyroid gland. The present study investigated the thyroid function of subjects with dental fluorosis from F-endemic areas of Gaya region, Bihar, India and compared it with control individuals from Bodh Gaya. The mean F concentration in groundwater of F-endemic area was 2.82 ± 0.18 mg/L (range 0.62–7.2 mg/L), while that of control area was 0.49 ± 0.04 mg/L (range 0.21–0.76 mg/L). Abnormal levels of T3, T4, and TSH were found in the study subjects from both control and F-endemic areas.     

Prostaglandin F2α facilitates female mating behavior based on male performance

Hormones play an important role in the regulation of reproductive behavior. Here, we examined the effects of the fatty acid derivative prostaglandin F2α (PGF2) on female sexual behavior as well as the interaction between PGF2-induced mating behavior with male courtship display in the lek-breeding African cichlid fish, Astatotilapia burtoni. In a two-way choice paradigm, we found that nonreproductive females preferred to associate with smaller, less aggressive males over larger, more aggressive males. However, PGF2-treated females dramatically reversed their preference to larger males. In a second experiment, PGF2 treatment dramatically increased sexual behavior in nonreproductive females as measured by time spent in the bower of the stimulus male, even when the female and the stimulus male were separated by a transparent divider. This effect was even more pronounced when the stimulus males were exposed to the putative female pheromone 17α,20β-progesterone (17α,20β-P). Under full-contact conditions, only PGF2-treated females visited a stimulus male’s bower, where they even displayed circling behavior usually only seen during spawning. Interestingly, male performance prior to PGF2 treatment predicted female sexual response. Our study demonstrates the importance of PGF2 in the control of female reproductive behavior in interaction with male performance.     

Habitat-induced changes in song consistency affect perception of social status in male chickadees

The ability of male black-capped chickadees to maintain consistent internal structure between successive iterations of their songs is affected by both their social rank and the quality of their habitat. Lab studies reveal that female chickadees discriminate between songs of dominant and subordinate males, which vary in acoustic structure. We investigate whether males also rely on acoustic structure to assess rival quality during agonistic interactions, and whether habitat-induced differences in song consistency affect the perception of male rank. We conducted a playback experiment to simulate territorial intrusions by dominant, stimuli males into the territories of dominant, subject males; stimuli males were recorded either in low-quality (young forest) or high-quality (mature forest) habitats. Stimuli from low-quality habitat had lower song consistency than those from high-quality habitats, despite being recorded from males of equivalent social rank. Subject males for playbacks (also socially dominant males) were chosen from either habitat type. Subject males in mature forest responded less to young-forest stimuli compared to mature-forest stimuli, despite the stimuli in both cases being recorded from dominant males. Conversely, male subjects in young forest did not differentiate between stimuli, but their response to both stimuli was lower than that of mature-forest subject males to mature-forest stimuli. We demonstrate that the ability to maintain internal song structure in the black-capped chickadee constitutes a signal that appears to be used by males to assess the level of threat of intruders, and that this perception is affected by habitat from which the stimulus males were recorded.     

Impacts of ocean acidification on marine shelled molluscs

Over the next century, elevated quantities of atmospheric CO₂ are expected to penetrate into the oceans, causing a reduction in pH (?0.3/?0.4 pH unit in the surface ocean) and in the concentration of carbonate ions (so-called ocean acidification). Of growing concern are the impacts that this will have on marine and estuarine organisms and ecosystems. Marine shelled molluscs, which colonized a large latitudinal gradient and can be found from intertidal to deep-sea habitats, are economically and ecologically important species providing essential ecosystem services including habitat structure for benthic organisms, water purification and a food source for other organisms. The effects of ocean acidification on the growth and shell production by juvenile and adult shelled molluscs are variable among species and even within the same species, precluding the drawing of a general picture. This is, however, not the case for pteropods, with all species tested so far, being negatively impacted by ocean acidification. The blood of shelled molluscs may exhibit lower pH with consequences for several physiological processes (e.g. respiration, excretion, etc.) and, in some cases, increased mortality in the long term. While fertilization may remain unaffected by elevated pCO₂, embryonic and larval development will be highly sensitive with important reductions in size and decreased survival of larvae, increases in the number of abnormal larvae and an increase in the developmental time. There are big gaps in the current understanding of the biological consequences of an acidifying ocean on shelled molluscs. For instance, the natural variability of pH and the interactions of changes in the carbonate chemistry with changes in other environmental stressors such as increased temperature and changing salinity, the effects of species interactions, as well as the capacity of the organisms to acclimate and/or adapt to changing environmental conditions are poorly described.     

Women’s self-perceived health and attractiveness predict their male vocal masculinity preferences in different directions across short- and long-term relationship contexts

Research has revealed that women’s self-perceived attractiveness positively predicts preferences for male facial and vocal masculinity, particularly in the context of long-term relationships. Other research has demonstrated that women who perceive themselves to be less healthy prefer male masculinity more than do women who may be healthier. As self-perceived health may predict self-perceived attractiveness, previous findings may appear to be contradictory. Therefore, we compared the effects of self-perceived attractiveness and self-perceived health on vocal masculinity preferences in long- and short-term relationship contexts. We found that although self-perceived health and attractiveness were positively correlated, self-rated attractiveness positively predicted long-term vocal masculinity preferences, whereas self-rated health negatively predicted short-term vocal masculinity preferences. While health and attractiveness may share a common basis, here we show independent potentially adaptive relationships with preferences based on relationship context. Such preferences are potentially adaptive as (a) masculine men may pass on inheritable immunity to infection to their offspring, which may be a relatively greater benefit for women in poor health; and (b) masculine men may be more likely to invest in relationships and offspring of relatively attractive women, decreasing the cost of choosing a masculine long-term partner for attractive women. These data resolve a potential conflict between health and attractiveness influences on the attractiveness of masculinity and highlight sophisticated individual differences in preferences.