In the present study, an underfloor air distribution (UFAD) system with a circular swirl diffuser was simulated in an office room using a three-dimensional model when thermal sources were present in the room. An Eulerian-Lagrangian model was used to predict the characteristics of air and particle phases. In the Lagrangian particle model, the effects of drag, lift, Brownian, and thermophoresis forces were considered. The results showed that the circular swirl diffuser has better airflow and thermal conditions compared with the circular direct diffusers. It was also shown that the studied UFAD system provides good thermal comfort condition. The local and mean normalized particle concentrations in different heights of the room were found reasonable, and the particle removal efficiency was between 55 and 65% for all the particle sizes. The results also showed that the large particles due to their large weight stayed in lower heights of the room and deposited on the floor. The particle concentration in the breathing zone of manikins was also investigated, and it showed that though the manikins seated close to inlet registers have appropriate thermal comfort, they encounter the highest particle concentration in their breathing zone.

Nonferrous metal smelting produces a large amount of Hg⁰ in flue gas, which has caused serious damage to the environment and human health. In this work, amorphous cobalt sulfide was synthesized by a liquid-phase precipitation method and was used for capturing gaseous Hg⁰ from simulated smelting flue gas at low temperatures (50~150 °C). In the adsorption process, Hg⁰ can be transformed into the stable mercury compound, which is confirmed to be HgS by X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption of Hg (Hg-TPD) analysis. Meanwhile, XPS results also demonstrate that S₂²⁻ species on the surface of cobalt sulfide play an important role in Hg⁰ transformation. At the temperature of 50 °C (inlet Hg⁰ concentration of 214 μg·m⁻³), the Hg⁰ adsorption capacity of cobalt sulfide (penetration rate of 25%) is as high as 2.07 mg·g⁻¹, which is much higher than that of popular adsorbents such as activated carbons and metal oxides. In addition, it was found that the Hg⁰ removal efficiency by cobalt sulfide in the flue gas with high concentration of SO₂ (5%) remained more than 94%. The good adsorption and Hg⁰ removal performance guarantee cobalt sulfide the great superiority and application potential in the treatment of Hg⁰ in smelting flue gas with high concentration of SO₂.

Graphene oxide (GO) has been reported to possess antibacterial activity; therefore, its accumulation in the environment could affect microbial communities such as biofilms. The susceptibility of biofilms to antimicrobials is known to depend on the stage of biofilm maturity. The aim of this study was to investigate the effect of GO nano-particles on Pseudomonas putida KT2440 biofilm of variable age. FT-IR, UV-vis, and Raman spectroscopy confirmed the oxidation of graphene while XPS confirmed the high purity of the synthesised GO over 6 months. Biofilms varying in maturity (24, 48, and 72 h) were formed using a CDC reactor and were treated with GO (85 μg/mL or 8.5 μg/mL). The viability of P. putida was monitored by culture on media and the bacterial membrane integrity was assessed using flow cytometry. P. putida cells were observed using confocal microscopy and SEM. The results showed that GO significantly reduced the viability of 48-h biofilm and detached biofilm cells associated with membrane damage while the viability was not affected in 24- and 72-h biofilms and detached biofilm cells. The results showed that susceptibility of P. putida biofilm to GO varied according to age which may be due to changes in the physiological state of cells during maturation. Graphical abstract

With the spread of the concept of sustainable development, people have gained awareness about the problem of massive illegal dumping of construction waste. In this research, a questionnaire survey was carried out in the USA and China. The results indicated the following. (1) Workers in both the countries had positive minimisation attitudes, and the attitude of Chinese construction workers was not significantly different from that of American construction workers. Furthermore, their average values were 3.9 and 4.07, respectively. (2) Business owners had a poor understanding of the obligations that should be fulfilled by contractors and construction workers, which greatly reduced (a) construction workers’ and contractors’ motivation to implement waste minimisation management and (b) the benefit-driven effect. (3) In terms of perceived behavioural control, Chinese construction workers had poorer minimisation technologies and knowledge than American construction workers, and it was very difficult for them to implement construction waste minimisation. The research conclusions and relevant suggestions may be used to improve the construction waste minimisation behaviour and awareness of Chinese people and promote China’s construction waste minimisation management.

This is a report on comprehensive characterization of cadmium (Cd)-exposed root proteomes in tomato using label-free quantitative proteomic approach. Two genotypes differing in Cd tolerance, Pusa Ruby (Cd-tolerant) and Calabash Rouge (Cd-sensitive), were exposed during 4 days to assess the Cd-induced effects on root proteome. The overall changes in both genotypes in terms of differentially accumulated proteins (DAPs) were mainly associated to cell wall, redox, and stress responses. The proteome of the sensitive genotype was more responsive to Cd excess, once it presented higher number of DAPs. Contrasting protein accumulation in cellular component was observed: Cd-sensitive enhanced intracellular components, while the Cd-tolerant increased proteins of extracellular and envelope regions. Protective and regulatory mechanisms were different between genotypes, once the tolerant showed alterations of various protein groups that lead to a more efficient system to cope with Cd challenge. These findings could shed some light on the molecular basis underlying the Cd stress response in tomato, providing fundamental insights for the development of Cd-safe cultivars. Graphical abstract

Iron (Fe) and manganese (Mn) are metals commonly found at high concentrations in underground water. These metals are essential for the good functioning of living organisms, but high concentrations lead to imbalance, potentiating the appearance of pathologies. This study aimed to evaluate the effect of exposure to naturally occurring metals in groundwater, using zebrafish (Danio rerio) as an experimental model. Thus, zebrafish were exposed to Fe (0.8 and 1.3 mg/L), Mn (0.2 and 0.4 mg/L), and groundwater collected from deep tube wells with Fe and Mn (Fe 0.8/Mn 0.2 mg/L and Fe 1.3/Mn 0.4 mg/L) for 30 days. Bioaccumulation of these metals has been demonstrated in the livers and muscles of zebrafish. Acetylcholinesterase activity changed only in zebrafish muscles in all groups. Sulfhydryl levels changed mainly in the group Mn 0.4. SOD/CAT ratio decreased in the groups Fe 0.8 and 1.3, Mn 0.4, and Fe 0.8/Mn 0.4. An increase in the frequency of micronucleus in all groups was shown as a consequence of these changes. Behavioral parameters (time and distance traveled, mean speed, turn angle, latency, and number of crossings between compartments) have also changed, mainly in the groups Fe 1.3, Mn 0.4, and Fe 1.3/Mn 0.4. Therefore, long-term exposure to Fe and Mn, even at not so high concentrations, may cause biochemical, genotoxic, and behavioral changes in zebrafish.

Breastfeeding is a gold standard of neonate nutrition because human milk contains a lot of essential compounds crucial for proper development of a child. However, milk is also a biofluid which can contain environmental pollution, which can have effects on immune system and consequently on the various body organs. Polychlorinated biphenyls are organic pollutants which have been detected in human milk. They have lipophilic properties, so they can penetrate to fatty milk and ultimately to neonate digestive track. Another problem of interest is the presence in milk of heavy metals—arsenic, lead, cadmium, and mercury—as these compounds can lead to disorders in production of cytokines, which are important immunomodulators. The toxicants cause stimulation or suppression of this compounds. This can lead to health problems in children as allergy, disorders in the endocrine system, end even neurodevelopment delay and disorder. Consequently, correlations between pollutants and bioactive components in milk should be investigated. This article provides an overview of environmental pollutants found in human milk as well as of the consequences of cytokine disorder correlated with presence of heavy metals. Graphical abstract

In order to understand the mechanism of the difference of Cd absorption and Cd enrichment in different ryegrass varieties, pot experiment was conducted to study on the response of two varieties of ryegrass (Bond and Abbott) to Cd stress as well as the differences of Cd uptake and expression of MT family genes and NRAMP2. Results showed that root dry weights of two varieties and shoot dry weights of Abbott increased first and then decreased with the increase of Cd level in soil. When exposed to 75 mg kg⁻¹ Cd, shoot dry weight and plant dry weight of Abbott both reached maximum values (10.92 and 12.03 g pot⁻¹), which increased by 11.09 and 10.67% compared with the control, respectively. Shoot dry weight and plant dry weight of Bond decreased with the increase of Cd level in soil. When the Cd level in soil was 75 mg kg⁻¹, shoot Cd concentrations of the two varieties were 111.19 mg kg⁻¹ (Bond) and 133.69 mg kg⁻¹ (Abbott), respectively, both of which exceeded the critical value of Cd hyperaccumulator (100 mg kg⁻¹). The expression of MT gene family and NRAMP2 in the leaf of Bond variety significantly increased at the Cd level of 75 mg kg⁻¹ and reached maximum value (except MT2C) at Cd level of 150 mg kg⁻¹. The expression of MT gene family in the stem of Bond variety showed a double-peak pattern, while the expression of NRAMP2 was a single-peak pattern. The expression of MT gene family and NRAMP2 in Abbott variety was consistent with single-peak pattern. The expression of MT gene family and NRAMP2 in leaf both significantly increased at Cd level of 150 mg kg⁻¹, while that in stem and root significantly increased at Cd level of 75 mg kg⁻¹. For both varieties of ryegrass, the expression amount of MT family genes and Nramp2 in leaf was higher than that in root and stem, indicating the Cd tolerance of ryegrass can be improved by increasing the expression levels of MT family genes and Nramp2 in stem and root. There was significant genotypic difference in the expression of MT gene family and NRAMP2 between the two varieties of ryegrass, and the expression of MT gene family and NRAMP2 in leaves and stems of Bond variety was higher than that in Abbott variety, while the expression of MT gene family and NRAMP2 in roots of Abbott variety was higher than that in Bond variety. The two gene families investigated in this study may be closely related to Cd uptake, but not related to Cd transport from root to leaf and Cd enrichment in shoot.

The present study aimed to determine the level of iron and calcium in the seminal plasma of men with different fertility potentials and to examine its relationship with oxidative stress. Seventy-nine sub-fertile patients with asthenoteratozoospermia (AT), n 27; teratoleucozoospermia (TL), n 20; teratozoospermia (Terato), n 32; and 29 healthy donors were included. The ability of spermatozoa to produce reactive oxygen species (ROS) was evaluated by using nitroblue tetrazolium (NBT) staining. The lipid peroxidation end product, malondialdehyde (MDA), and the trace element levels (iron and calcium) were measured spectrophotometrically. Iron and calcium concentrations in seminal plasma of the patient groups were significantly more elevated than the normal group. Nevertheless, both calcium and iron showed strong negative correlations with the total sperm motility and normal sperm morphology, but only iron was positively and significantly associated with multiple anomalies index and seminal leucocyte concentration. On the other hand, the rates of MDA and ROS production in semen were significantly higher in the three abnormal groups than in controls. These two oxidative stress biomarkers were significantly associated with the percentage of atypical forms in semen. However, only semen ROS level was significantly associated with the decreased sperm motility and the sperm leucocytes concentration. Meanwhile, there are positive correlations between seminal iron and calcium content and the studied oxidative stress biomarkers. Oxidative stress and trace element excess are implicated in low sperm quality. Iron and calcium might be the mediators of the effects of oxidative damage and induces lipid peroxidation.

Photocrosslinked silicone acrylates are used in a variety of applications, such as printing inks, adhesives, or adhesive release liners. Their production requires the use of a photoinitiator. Even if the photoinitiator represents a minor mass in the photocurable formulation (2–10%), it is used in excess and residual amounts may therefore remain in the polymerized products and possibly migrate into the environment during the use of the products and/or at their end-of-life stage. Little is known on the possible degradation of silicone acrylate which may increase the potential release. The present study investigated the release of Darocur 1173, the most commonly used photoinitiator, from silicone matrix and the effect of accelerated photoageing on the extent of the phenomenon. Leaching tests in water were conducted on thin-coated plastic film (release liners) made of a mixture of polypropylene and polyethylene. Results showed that 44% of the Darocur 1173 photoinitiator initially used in silicone formulation was released from silicone matrix in the leaching test. Accelerated photoageing obtained by UV irradiation of the films for up to 200 h was found to favor photoinitiator degradation but also induced a strong and fast oxidation of silicone-coated liners as compared to that of uncoated ones. Graphical abstract