Disinfection by-product (DBP) research in China: Are we on the track?

Disinfection by-products (DBPs) formed during water disinfection has drawn significant public concern due to its toxicity. Since the first discovery of the trihalomethanes in 1974, continued effort has been devoted on DBPs worldwide to investigate the formation mechanism, levels, toxicity and control measures in drinking water. This review summarizes the main achievements on DBP research in China, which included: (1) the investigation of known DBP occurrence in drinking water of China; (2) the enhanced removal of DBP precursor by water treatment process; (3) the disinfection optimization to minimize DBP formation; and (4) the identification of unknown DBPs in drinking water. Although the research of DBPs in China cover the whole formation process of DBPs, there is still a challenge in effectively controlling the drinking water quality risk induced by DBPs, an integrated research framework including chemistry, toxicology, engineering, and epidemiology is especially crucial.     

Are the TTAGG and TTAGGG telomeric repeats phylogenetically conserved in aculeate Hymenoptera?

Despite the (TTAGG)_n telomeric repeat supposed being the ancestral DNA motif of telomeres in insects, it was repeatedly lost within some insect orders. Notably, parasitoid hymenopterans and the social wasp Metapolybia decorata (Gribodo) lack the (TTAGG)_n sequence, but in other representatives of Hymenoptera, this motif was noticed, such as different ant species and the honeybee. These findings raise the question of whether the insect telomeric repeat is or not phylogenetically predominant in Hymenoptera. Thus, we evaluated the occurrence of both the (TTAGG)_n sequence and the vertebrate telomere sequence (TTAGGG)_n using dot-blotting hybridization in 25 aculeate species of Hymenoptera. Our results revealed the absence of (TTAGG)_n sequence in all tested species, elevating the number of hymenopteran families lacking this telomeric sequence to 13 out of the 15 tested families so far. The (TTAGGG)_n was not observed in any tested species. Based on our data and compiled information, we suggest that the (TTAGG)_n sequence was putatively lost in the ancestor of Apocrita with at least two subsequent independent regains (in Formicidae and Apidae).     

Bio-remediation of acephate–Pb(II) compound contaminants by Bacillus subtilis FZUL-33

Removal of Pb~(2+)and biodegradation of organophosphorus have been both widely investigated respectively. However, bio-remediation of both Pb~(2+)and organophosphorus still remains largely unexplored. Bacillus subtilis FZUL-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of Pb~(2+)and biodegradation of acephate. In the present study, both Pb~(2+)and acephate were simultaneously removed via biodegradation and biomineralization in aqueous solutions.Batch experiments were conducted to study the influence of p H, interaction time and Pb~(2+)concentration on the process of removal of Pb2+. At the temperature of 25°C, the maximum removal of Pb~(2+)by B. subtilis FZUL-33 was 381.31 ± 11.46 mg/g under the conditions of p H 5.5, initial Pb~(2+)concentration of 1300 mg/L, and contact time of 10 min. Batch experiments were conducted to study the influence of acephate on removal of Pb~(2+)and the influence of Pb2+on biodegradation of acephate by B. subtilis FZUL-33. In the mixed system of acephate–Pb2+, the results show that biodegradation of acephate by B. subtilis FZUL-33 released PO43+, which promotes mineralization of Pb2+. The process of biodegradation of acephate was affected slightly when the concentration of Pb2+was below 100 mg/L. Based on the results, it can be inferred that the B. subtilis FZUL-33 plays a significant role in bio-remediation of organophosphorus-heavy metal compound contamination.     

Informal knowledge processes: the underpinning for sustainability outcomes in EIA?

Environmental Impact Assessment (EIA) was originally tailored for restructuring rules and values regarding environmental protection, through interdisciplinary work. EIA has developed as a tool for decision-making for the implementation of projects which potentially pose significant environmental impacts. This paper reviews the sustainability and interdisciplinarity assumptions inherent in EIA. It illustrates through a case study of a proposed landfill extension in Rio Grande do Sul, Brazil, that these principles can arise more from informal knowledge processes than from legal ones. It can be shown that interdisciplinarity is often misunderstood as multidisciplinarity or simple knowledge clustering, and sustainability has no common definition amongst EIA practitioners, but that there predominates an understanding which delivers weak sustainability, driven primarily by social and economic goals. The conclusion is that EIA cannot achieve the original vision set out in the world's first legislation adopted in 1970 unless a learning-organization approach is taken whereby: the critical role of informal knowledge is recognized; informal knowledge is properly managed by EIA teams to engender a common understanding of sustainable development goals; interdisciplinary and transdisciplinary working practices are adopted.     

Adsorption and desorption of Cu(Ⅱ) and Pb(Ⅱ) in paddy soils cultivated for various years in the subtropical China

The adsorption and desorption of Cu(Ⅱ) and Pb(Ⅱ) on upland red soil,and paddy soils which were originated from the upland soil and cultivated for 8,15,35 and 85 years,were investigated using the batch method.The study showed that the organic matter content and cation exchange capacity (CEC) of the soils are important factors controlling the adsorption and desorption of Cu(Ⅱ) and Pb(Ⅱ).The 15-Year paddy soil had the highest adsorption capacity for Pb(Ⅱ),followed by the 35-Year paddy soil.Both the 35-Year paddy soil and 15-Year paddy soil adsorbed more Cu(Ⅱ) than the upland soil and other paddy soils.The 15-Year paddy soils exhibited the highest desorption percentage for both Cu(Ⅱ) and Pb(Ⅱ).These results are consistent with the trend for the CEC of the soils tested.The high soil CEC contributes not only to the adsorption of Cu(Ⅱ) and Pb(Ⅱ) but also to the electrostatic adsorption of the two heavy metals by the soils.Lower desorption percentages for Cu(Ⅱ) (36.7% to 42.2%) and Pb(Ⅱ) (50.4% to 57.9%) were observed for the 85-Year paddy soil.The highest content of organic matter in the soil was responsible for the low desorption percentages for the two metals because the formation of the complexes between the organic matter and the metals could increase the stability of the heavy metals in the soils.     

Environmental threats to the Three Gorges Reservoir Region:Are mutagenic and genotoxic substances important?

<正>The Three Gorges Dam project(TGDP),with a total static investment of 95.46 billion RMB(US$10.97 billion)based on the 1993 price level,commenced in 1994 and was completed in 2012.The creation of the Three Gorges Reservoir following the completion of the TGDP had brought about significant changes to the Three Gorges Reservoir Region(TGRR),stretching from the town of Sandouping in Hubei Province to the Jiangjin District of Chongqing Municipality.The TGDP has led to progressive urbanization and industrialization of the TGRR,accompanied by increased shipping activities,greater     

Does the energy labelling system for domestic tumble dryers serve its purpose?

Tumble dryers sold on the market today are labelled according to their energy efficiency. This labelling system has primarily two purposes: to guide buyers to a product with low energy use, lower cost and lower environmental impact and to encourage producers to develop even more energy-efficient products. Tumble dryers are optimized for their maximum capacity, which is used as the standard load for determining the energy label. Three different tumble dryers have been tested with different drying loads. Results indicate that all the tested tumble dryers have significantly lower energy efficiency when drying small loads. In order to encourage the development of tumble dryers with high energy efficiency at drying loads used in ordinary households, the standards for the energy labelling system should be revised.     

TiO_2/beads as a photocatalyst for the degradation of X_(3B) azo dye

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Alkynyl carbon materials as novel and efficient sorbents for the adsorption of mercury(Ⅱ) from wastewater

For the first time, a series of alkynyl carbon materials(ACMs) were prepared via the mechanochemical reaction of CaC_2 with six polyhalogenated precursors, namely CCl_4,C_2Cl_6, C_2Cl_4, C_6Cl_6, C_6Br_6, and C_(14)H_4Br_(10)(ACM-1, ACM-2, ACM-3, ACM-4, ACM-5, and ACM-6,respectively) and used for the adsorptive removal of mercury from aqueous solutions.Based on preliminary investigations, the adsorption of mercury on ACM-5 was studied in depth. Specifically, the effect of p H on mercury adsorptivity, adsorption kinetics,thermodynamics, isotherms, and recyclability was studied. The adsorptivity of mercury on ACMs was found to be closely related to the hydrocarbon precursor, specific surface area of sorbent, and the alkynyl content. ACM-5 showed the best performance and is among the best raw carbonaceous sorbents reported so far, with a Langmuir saturated adsorption capacity of 191.9 mg g~(-1). The promising mercury adsorption performance mainly arises from the strong Lewis soft acid–soft base interactions between the alkynyl groups and mercury ions. The adsorption isotherms could be satisfactorily correlated with the Langmuir equation. The results show that the ACMs can be used as efficient sorbents for the removal of mercury and may also be useful for the adsorption of other heavy metals.     

Advanced analytical determination of volatile organic compounds (VOC) and other major contaminants in water samples using GC-Ion Trap MS

ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｇｎｉｆｉｃａｎｔｗａｔｅｒｑｕａｌｉｔｙｍａｎａｇｅｍｅｎｔｆｏｒｍｉｔｉｇａｔｉｏｎｏｆｅｎｖｉｒｏｎｍｅｎｔａｌｐｏｌｌｕｔｉｏｎｃａｕｓｅｄｂｙｈａｚａｒｄｏｕｓｃｈｅｍｉｃａｌｓｉｓｓｔｉｌｌａｍａｔｔｅｒｏｆｓｔｒｉｎｇｅｎｔｅｎｖｉｒｏｎｍｅｎｔａｌｃｏｎｓｉｄｅｒａｔｉｏｎｉｎＪａｐａｎ .Ｓｕｂｓｅｑｕｅｎｔｌｙ,ｒｅｇｕｌａｒｏｎ ｇｏｉｎｇｍｏｎｉｔｏｒｉｎｇａｒｅｉｍｐｌｅｍｅｎｔｅｄ ,ｅｓｐｅｃｉａｌｌｙｆｏｒｓｙｎｔｈｅｔｉｃｃｈｅｍｉｃａｌｓ…     

Adsorption and mechanistic study of the invasive plant-derived biochar functionalized with CaAl-LDH for Eu(Ⅲ) in water

Herein,we developed the invasive plant-derived biochar (IPB) functionalized with CaAl-LDH at five mass ratios using a physical mixture method,assessed their adsorption perform for Eu(Ⅲ),and explored the relative mechanisms.Results show that the IPB successfully loaded CaAl-LDH in five composites and their Eu(Ⅲ) sorption affinities were strongly affected by solution p H,contact time,temperature,and the mass ratio of LDH and IPB.All the sorpiton process for Eu(Ⅲ) occurred on the heterogeneous surf...     

Fetoscopic myelomeningocoele closure: Is the scientific evidence enough to challenge the gold standard for prenatal surgery?

Since the completion of the Management of Myelomeningocoele Study, maternal-fetal surgery for spina bifida has become a valid option for expecting parents. More recently, multiple groups are exploring a minimally invasive approach and recent outcomes have addressed many of the initial concerns with this approach. Based on a previously published framework, we attempt to delineate the developmental stage of the surgical techniques. Furthermore, we discuss the barriers of performing randomized controlled trials comparing two surgical interventions and suggest that data collection through registries is an alternative method to gather high-grade evidence.     

A collaborative strategy for enhanced reduction of Cr(Ⅵ) by Fe(0) in the presence of oxalate under sunlight:Performance and mechanism

Nanometer-size zero-valent iron(NZVI) is an efficient reducing agent,but its surface is easily passivated with an oxide layer,leading to reaction inefficiency.In our study,oxalate(OA) was introduced into this heterogeneous system of NZVI,which could form ferrioxalate complexes with the NZVI surface-bound Fe~(3+) and dissolved Fe~(3+) in the solution.Photolysis of ferrioxalate complexes can facilitate the generation of Fe~(2+) from Fe~(3+)and CO_2~(·-) radical,both species have strong reduction capacity.Hence,a "photo-oxalate-Fe(0)"system through sunlight induction was established,which not only prohibited the formation of a surface passivation layer,but also displayed a synergetic mechanism of ferrioxalate photolysis to enhance reduction,exhibiting remarkably higher degradation activity(several times faster) toward the model pollutant Cr(Ⅵ) than the mechanism with NZVI alone.Factor tests suggested that both NZVI dosage and OA content markedly affected the reduction rate.Low pH was beneficial to the reduction efficiency.Moreover,recyclability experiment showed that the reduction rate decreased from 0.21706 to 0.03977 min~(-1) after three cycles of reuse due to the NZVI losing reaction activity generally,but the system still maintained considerable reduction capacity.Finally,a mechanism was revealed whereby NZVI would transform to Fe oxides after the exhaustion of its reductive power,and the photolysis of ferrioxalate to promote the cycling of iron species played the predominant role in providing extra reduction ability.These features confirm that introduction of OA into Cr(Ⅵ) reduction by NZVI through sunlight induction is advantageous and promising.     

What’s the buzz? Ultrasonic and sonic warning signals in caterpillars of the great peacock moth (Saturnia pyri)

Caterpillars have many natural enemies and, therefore, have evolved a diversity of antipredator strategies. Most research focuses on those strategies (crypsis, countershading, and warning coloration) targeting visually guided predators. In contrast, defensive sounds, although documented for more than a century, have been poorly studied. We report on a novel form of sound production—chirping—in caterpillars of the common European Great Peacock moth (Saturnia pyri). Chirps are broadband, with dominant peaks ranging between the sonic (3.7 kHz) and ultrasonic (55.1 kHz) and are generated by a rapid succession of mandibular “tooth strikes.” Chirp trains are induced by simulated predator attacks and precede or accompany the secretion of a defensive chemical from integumental bristles, supporting our hypothesis that these sounds function in acoustic aposematism. We propose that these caterpillars generate multimodal warning signals (visual, chemical, and acoustic) to target the dominant sensory modalities of different predators, including birds, bats, and invertebrates. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

What is the maximum potential for CO2 sequestration by “stimulated” weathering on the global scale?

Natural chemical weathering of silicate rocks is a significant sink for soil and atmospheric CO₂. Previous work suggested that natural chemical weathering may be stimulated by applying finely ground silicate rocks to agricultural areas or forests [stimulated weathering (SW)]. However, it remained unknown if this technique is practical to sequester globally significant amounts of CO₂ under realistic conditions. Applying first estimates of “normal treatment” amounts from a literature review, we report here a theoretical global maximum potential of 65 10⁶ t sequestered C a⁻¹ if SW would be applied homogenously on all agricultural and forested areas of the world. This is equivalent to 0.9% of anthropogenic CO₂ emissions (reference period 2000–2005). First, however, the assumed application of SW on most of the considered areas is not economically feasible because of logistic issues, and second the net-CO₂ sequestration is expected to amount to only a fraction of consumed CO₂ due to the energy demand of the application itself (currently ~11%). Unless progress in application procedures is provided, the recent realistic maximum net-CO₂-consumption potential is expected to be much smaller than 0.1% of anthropogenic emissions, and the SW would thus not be one of the key techniques to reduce atmospheric CO₂ concentration. However, literature suggests that for some agricultural areas (croplands) and specifically for rice production areas in humid climates, this SW may be a feasible tool to support international efforts to sequester CO₂. SW may be cost effective for those areas if linked to the CO₂-emission certificate trade in the future, and increases in crop production are taken into account.