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Germination events of plants often occur after rainfall in saline environments where the soil salinity is diluted, viz recovery germination. Previous germination studies have rarely considered the duration of exposure to salt stress, and none of them have investigated recovery germination under low-salt concentration, other than in distilled water. The main objective of this study was to investigate the effects of salinity, exposure duration and low-salt recovery solutions on seed germination of the weed Chenopodium acuminatum to get a clear insight about the germination strategy exhibited by this species in a saline habitat. Seeds were initially exposed to 0–400 mM NaCl for 10, 20 and 30 d. The subsequent recovery experiment was conducted differently. For those initially treated with 100 and 200 mM NaCl, the recovery solution was distilled water, while for those initially treated with 300 and 400 mM NaCl, the recovery solution was distilled water, at 50 and 100 mM NaCl. Results showed that the recovery germination percentage and rate significantly decreased when the exposure duration extended. Seeds could subsequently recover to germinate at high percentages at recovery salt solution concentrations for a short duration, but the recovery percentages and rates in high salinity, combined with high exposure duration and relatively high recovery salt concentrations, were remarkably lower. More than 30% of the ungerminated seeds were viable after the recovery experiment. We suggest that Ch. acuminatum exhibits a ‘cautious’ strategy of germination to avoid injury from long-term salt stress and ensure survival for the subsequent continuation of its population under unfavorable saline conditions.

Agricultural machineries as one of the main inputs in producing agricultural materials are associated with some problems on occupational health such as vibrations. At the lowest level, vibrations cause different diseases such as those affecting blood vessels, nerves, muscles, etc. The aim of this study was to determine and investigate the seat vibrations in John Deere 1055I combine harvester at different conditions. The experiments were carried out based on ISO 2631 and the Iranian standard number 14133. The tests were done at different engine revolutions and gear ratios with three replications. The collected data were analyzed considering factorial experiments based on completely randomized design. The results of variance analysis related to the effect of the main factors on combine seat vibrations showed a significant difference at the probability level of 1%. Effect of engine revolutions on vibration of the combine seat was higher than that of shifting gears. By calculating the allowable exposure time, there was concluded that for the first and second gears at the engine revolution of 1800 rpm and the first gear at the revolution of 2500 rpm, operators can easily drive the combine harvester for eight hours every day without any problems. The results of this study can be used to optimize the components affecting the vibration of the combine seat.

Global warming appears to favour smaller-bodied organisms, but whether larger species are also more vulnerable to thermal extremes, as suggested for past mass-extinction events, is still an open question. Here, we tested whether interspecific differences in thermal tolerance (heat and cold) of ectotherm organisms are linked to differences in their body mass and genome size (as a proxy for cell size). Since the vulnerability of larger, aquatic taxa to warming has been attributed to the oxygen limitation hypothesis, we also assessed how body mass and genome size modulate thermal tolerance in species with contrasting breathing modes, habitats and life stages. A database with the upper (CTmax) and lower (CTmin) critical thermal limits and their methodological aspects was assembled comprising more than 500 species of ectotherms. Our results demonstrate that thermal tolerance in ectotherms is dependent on body mass and genome size and these relationships became especially evident in prolonged experimental trials where energy efficiency gains importance. During long-term trials, CTmax was impaired in larger-bodied water-breathers, consistent with a role for oxygen limitation. Variation in CTmin was mostly explained by the combined effects of body mass and genome size and it was enhanced in larger-celled, air-breathing species during long-term trials, consistent with a role for depolarization of cell membranes. Our results also highlight the importance of accounting for phylogeny and exposure duration. Especially when considering long-term trials, the observed effects on thermal limits are more in line with the warming-induced reduction in body mass observed during long-term rearing experiments. This article is part of the theme issue ‘Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen’.

The mobility and distribution of metals in the environment is related not only to their concentration but also to their availability in the environment. Most chromium (Cr) exists in oxidation states ranging from 0 to VI in soils but the most stable and common forms are Cr(0), Cr(III), and Cr(VI) species. Chromium can have positive and negative effects on health, according to the dose, exposure time, and its oxidation state. The last is highly soluble; mobile; and toxic to humans, animals, and plants. On the contrary, Cr(III) has relatively low toxicity and mobility and it is one of the micronutrients needed by humans. In addition, Cr(III) can be absorbed on the surface of clay minerals in precipitates or complexes. Thus, the approaches converting Cr(VI) to Cr(III) in soils and waters have received considerable attention. The Cr(III) compounds are sparingly soluble in water and may be found in water bodies as soluble Cr(III) complexes, while the Cr(VI) compounds are readily soluble in water. Chromium is absorbed by plants through carriers of essential ions such as sulfate. Chromium uptake, accumulation, and translocation, depend on its speciation. Chromium shortage can cause cardiac problems, metabolic dysfunctions, and diabetes. Symptoms of Cr toxicity in plants comprise decrease of germination, reduction of growth, inhibition of enzymatic activities, impairment of photosynthesis and oxidative imbalances. This review provides an overview of the chemical characteristics of Cr, its behavior in the environment, the relationships with plants and aspects of the use of fertilizers.

We report the fabrication, electrical, and optical characterizations of few-layered black phosphorus (BP)-based field-effect transistor (FET). The fabricated device exhibits a p-type transport with hole mobility up to 175 cm 2  V −1  s −1 at V ds  = 1 mV. The transfer characteristics show a large hysteresis width that depends linearly on the gate voltage and decreases with the increasing drain bias. The fabricated device also ensures a non-volatile charge-trap memory behaviour, with a stable and long retention time. The material’s photodetection capabilities enhance the functionality of the device making it controllable by light. The photocurrent was observed to be linearly increasing with the light incident power and exposure time. As a photodetector, the transistor reaches a responsivity and detectivity up to 340 mA W −1 and 6.52 × 10 11 Jones under white light at 80  mW , respectively. Time-resolved measurements provide evidence of a long single exponential decay process through deep intra-gap states. Our results highlight the potential of a few layers BP as a nanomaterial for field-effect, memory, and optoelectronic devices. Graphical Abstract

Evaluation of groundwater quality and related health hazards is a prerequisite for taking preventive measures. The rural region of Telangana, India, has been selected for the present study to assess the sources and origins of inferior groundwater quality and to understand the human health risk zones for adults and children due to the consumption of nitrate ( NO 3 - )- and fluoride (F − )-contaminated groundwater for drinking purposes. Groundwater samples collected from the study region were determined for various chemical parameters. Groundwater quality was dominated by Na + and HCO 3 - ions. Piper’s diagram and bivariate plots indicated the carbonate water type and silicate weathering as a main factor and man-made contamination as a secondary factor controlling groundwater chemistry; hence, the groundwater quality in the study region is low. According to the Groundwater Quality Index (GQI) classification, 48.3% and 51.7% of the total study region are excellent (GQI: < 50) and good (GQI: 50 to 100) water quality types, respectively, for drinking purposes. However, NO 3 - ranged from 0.04 to 585 mg/L, exceeding the drinking water quality limit of 45 mg/L in 34% of the groundwater samples due to the effects of nitrogen fertilizers. This was supported by the relationship of NO 3 - with TDS, Na + , and Cl − . The F − content was from 0.22 to 5.41 mg/L, which exceeds the standard drinking water quality limit of 1.5 mg/L in 25% of the groundwater samples. The relationship of F − with pH, Ca 2+ , Na + , and HCO 3 - supports the weathering and dissolution of fluoride-rich minerals for high F − content in groundwater. They were further supported by a principal component analysis. The Health Risk Index (HRI) values ranged from 0.20 to 20.10 and 0.36 to 30.90 with a mean of 2.82 and 4.34 for adults and children, respectively. The mean intensity of HRI (> 1.0) was 1.37 times higher in children (5.70) than in adults (4.16) due to the differences in weight size and exposure time. With an acceptable limit of more than 1.0, the study divided the region into Northern Safe Health Zone (33.3% for adults and 28.1% for children) and Southern Unsafe Health Zone (66.7% for adults and 71.9% for children) based on the intensity of agricultural activity. Therefore, effective strategic measures such as safe drinking water, denitrification, defluoridation, rainwater harvesting techniques, sanitary facilities, and chemical fertilizer restrictions are recommended to improve human health and protect groundwater resources.

Each year, 5 to 10 million tons of plastic waste is dumped in the oceans via freshwaters and accumulated in huge oceanic gyres. Under the effect of several abiotic factors, macro plastic wastes (or plastic wastes with macro sizes) are fractionated into microplastics (MP) and finally reach the nanometric size (nanoplastic NP). To reveal potential toxic impacts of these NPs, two microalgae, Scenedemus subspicatus (freshwater green algae), and Thalassiosira weissiflogii (marine diatom) were exposed for up to 48 h at 1, 10, 100, 1000, and 10,000 μg/L to reference polyethylene NPs (PER) or NPs made from polyethylene collected in the North Atlantic gyre (PEN, 7th continent expedition in 2015). Freshwater filter-feeding bivalves, Corbicula fluminea, were exposed to 1000 μg/L of PER and PEN for 48 h to study a possible modification of their filtration or digestion capacity. The results show that PER and PEN do not influence the cell growth of T. weissiflogii, but the PEN exposure causes growth inhibition of S. subspicatus for all exposure concentrations tested. This growth inhibition is enhanced for a higher concentration of PER or PEN (10,000 μg/L) in S. subspicatus. The marine diatom T. weissiflogii appears to be less impacted by plastic pollution than the green algae S. subspicatus for the exposure time. Exposure to NPs does not lead to any alteration of bivalve filtration; however, fecal and pseudo-fecal production increased after PEN exposure, suggesting the implementation of rejection mechanisms for inedible particles.

An important issue in assessing microplastics is whether this newly emerging type of pollution affects freshwater invertebrates. This study was designed to examine the interactions between the amphipod Gammarus fossarum and two types of microplastics. To determine the ingestion and egestion of polyamide (PA) fibres (500 × 20 μm), amphipods were exposed to four concentrations (100, 540, 2680, 13,380 PA fibres cm −2 base area of glass beakers) and four exposure times (0.5, 2, 8, 32 h) as well as four post-exposure times (1, 2, 4, 16 h). We demonstrate a positive correlation between concentration and ingestion of PA fibres. Fibres were found in the gut after 0.5 h of exposure. Egestion was rapid and the digestive tract was empty 16 h after exposure ended. To investigate whether polystyrene (PS) beads (1.6 μm) can be taken up in the epithelial cells of the gut and the midgut glands, four concentrations (500, 2500, 12,500, 60,000 PS beads mL −1 ) were tested. Cryosections exhibited fluorescent PS beads only within the gut lumen. In a 28-day feeding experiment with both, fibres and beads, we studied the amphipod’s feeding rate, assimilation efficiency and wet weight change. The exposure to PA fibres (2680 PA fibres cm −2 base area of glass beakers) significantly reduced the assimilation efficiency of the animals. While both tested polymer types are ingested and egested, PA fibres can impair the health and ecological functions of freshwater amphipods under continuous exposure.

Atmospheric cold plasma (ACP) is an emerging technology which has increased attraction due to the consumers’ tendency toward fresh and minimally processed food products. This non-thermal technology has been considered as a promising tool for decontamination of foods, modification of food components as well as food packaging. The potential interactions of cold plasma species with food components and consequently its effect on food quality is of high importance. Proteins are the main food constituent in food formulations regarding both nutritional and technological points of view. The susceptibility of native proteins to reactive species created through ACP treatment should be considered regarding the power supply, type of feeding gas and its pressure, exposure time, input voltage and current flow. However, the protein characteristics and the manner in which they are exposed are also important to be considered. This review article is aimed to investigate the technological and nutritional characteristics of proteins during atmospheric cold plasma treatment.

Increasing cadmium (Cd) pollution in agricultural soils has raised serious concerns worldwide. Several exogenous substances can be used to mitigate the toxic effects of Cd in plants. Zinc (Zn) is one of the essential plant micronutrients and is involved in several physiological functions in plants. Zn may alleviate Cd toxicity in plants owing to the chemical similarity of Zn with Cd. Published reports demonstrated that Zn can alleviate toxic effects of Cd in plants by increasing plant growth, regulating Cd uptake, increasing photosynthesis, and reducing oxidative stress. Literature demonstrated that the role of Zn on Cd accumulation by plants is very controversial and depends upon several factors including concentrations of Cd and Zn in the medium, exposure duration, plant species and genotypes, and growth conditions. This review highlights the role of Zn in reducing Cd toxicity in plants and provides new insight that proper level of Zn in plants may enhance plant resistance to excess Cd.