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The removal potential of cadmium (Cd(II)) from aqueous solution by waste mango kernel biochar (MKB) was investigated for the first time. MKB was prepared by pyrolyzing mango kernel waste at 300–700 °C for 2 h. The effects of pyrolysis temperature on physicochemical characteristics of MKB were described by Brunauer–Emmett–Teller (BET), scanning electron micrographs with energy dispersive system (SEM–EDS), Fourier transform infrared (FTIR), and X-ray diffractometer (XRD). Batch adsorption experiments were also performed to study adsorption properties for Cd(II) of MKB. The results indicated that the pH, C content, specific surface area, and pore volume increased obviously with the pyrolysis temperature increased, while the element ratio and surface functional groups decreased. The variation of Cd(II) adsorption capacity with time and initial concentration were better fitted by pseudo-second-order and Langmuir isotherm models, respectively, indicating that the MKB adsorption process was a monolayer adsorption dominated by chemical adsorption. Increasing the pyrolysis temperature increased the maximum adsorption capacity and MKB700 had the highest Langmuir sorption capacity for Cd(II) (27.81 mg g−1) at pH 6.0. Multiple consecutive adsorption–desorption cycles revealed the good reusability of MKB. Further analysis showed that the Cd(II) adsorption mechanism on MKB700 was primarily attributed to complexation reaction with functional groups, ion exchange, and precipitation reaction. This study demonstrated that MKB could be a low-cost and recyclable adsorbent, which could be a promising method of mango kernel waste resourceful treatment.

Woody orchard wastes have caused tremendous pressure on the environment. In the study, Ficus caricabranch (FB) wastes were recycled and prepared for biochars (FBBs) through pyrolytic technique and the characteristics of FBBs, their Cd2+adsorption behaviors and mechanism in solution were investigated. The FBBs yield, H, N and O contents and hydrophilicity decreased, but the pH, Si, C and ash contents, aromaticity, specific surface area, total pore volume, and stability increased with the increase of pyrolysis temperature. Meanwhile, significant morphological and functional groups changes were observed with increasing pyrolysis temperature. The optimum Cd2+adsorption conditions were pH 6 and dosage of 5 g·L−1. The Cd2+adsorption capacities of all the FBBs were well described by pseudo-second-order and Langmuir isotherm models and the maximum adsorption capacity was 34.85 mg·g−1for FBB800. The adsorption of FBB800 was spontaneous. Moreover, the selective adsorption sequence was in the order of Cd2+> Pb2+> Cu2+> Zn2+. After 5 cycles, the adsorption efficiency could still reach 80%. Precipitation with minerals and surface functional group complexation were the dominant mechanism for Cd2+adsorption. The results indicated that the FBBs could be applied as a low-cost adsorbent to remove Cd2+effectively from aqueous solutions.

The overall health condition of patients significantly affects the diagnosis, treatment, and prognosis of endodontic diseases. A systemic consideration of the patient’s overall health along with oral conditions holds the utmost importance in determining the necessity and feasibility of endodontic therapy, as well as selecting appropriate therapeutic approaches. This expert consensus is a collaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence, aiming to provide general guidance on clinical procedures, improve patient safety and enhance clinical outcomes of endodontic therapy in patients with compromised overall health.

Biochar has been widely recognized as an environmentally efficient adsorbent for removal of heavy metals in wastewater. However, inferior adsorption capacity limits its practical application. In this study, a H3PO4–modified tea branch biochar (PTBB) was firstly prepared through the one step pyrolysis of H3PO4-pretreated tea branch powder for enhancing removal efficiency of Cd2+and Pb2+from aqueous solutions. H3PO4modification altered the physicochemical properties of pristine biochar. The PTBB exhibited superior adsorption performance. Its maximum adsorption capacities of Cd2+and Pb2+were 98.25 mg g−1and 127.5 mg g−1at the pH 6 and dosage of 2 g L−1, which was 1.5 and 1.3 folds of the pristine biochar, respectively. Cd2+and Pb2+adsorption data by PTBB were well fitted by the Langmuir isothermal and pseudo-second order kinetic models, indicating monolayer chemical adsorption controlled the adsorption process. The adsorption of Cd2+and Pb2+by PTBB was a spontaneous endothermic process and less affected by coexisting cations. PTBB demonstrated a greater affinity for Pb2+as compared with Cd2+in binary metal systems. Moreover, PTBB could maintain good stability and regeneration properties. The adsorption of Cd2+and Pb2+by PTBB was attributed to cation exchange, precipitation, complexation, and π electron interactions. The quantitative analysis indicated that complexation and precipitation were the primary adsorption mechanisms, which accounted for 50.52–50.56% and 36.7–42.18% to total Cd2+and Pb2+adsorption for PTBB, respectively. Therefore, PTBB exhibits great potential for application in the remediation of wastewater containing Cd2+or Pb2+.

Hydrogel systems promote the development of flexible energy storage devices because of their inherent mechanical elasticity and ionic conductivity. However, achieving stable energy storage capacity under violent mechanical deformation is still a challenge for hydrogel devices. In this work, an all-in-one integrated supercapacitor (AISC) was assembled using in situdeposited polyaniline/graphene oxide nanocomposites for both sides of the incorporated ionic hydrogel electrolyte. The assembly process of the AISC was greatly simplified, and the displacement and separation of the multilayer structured hydrogel complex were avoided during mechanical deformation. The hydrogel electrolyte with ionic additives exhibited strong adhesion and flexibility, and high ionic conductivity, thereby ensuring the excellent specific capacitance and rate performance of the AISC. The specific capacitances of the AISC were 222.8 mF cm−2at the current density of 0.2 mA cm−2and 151.7 mF cm−2at 3.2 mA cm−2. The capacitance retention rate was 68.1%. The energy density of a piece of the device reached 44.6µW h cm−2at a power density of 120.0 µW cm−2. Moreover, reliable and reproducible energy storage was acquired under bending, compression, and stretching deformations. The AISC was also easily assembled in series to power a light-emitting diode (LED) light. This work provides a facile approach to the construction of flexible supercapacitors for the development of energy storage devices in flexible electronics.

The evolution of mining-induced stress field in longwall panel is closely related to the fracture field and the breaking characteristics of strata. Few laboratory experiments have been conducted to investigate the stress field. This study investigated its evolution by constructing a large-scale physical model according to the in situ conditions of the longwall panel. Theoretical analysis was used to reveal the mechanism of stress distribution in the overburden. The modelling results showed that: (1) The major principal stress field is arch-shaped, and the strata overlying both the solid zones and gob constitute a series of coordinated load-bearing structures. The stress increasing zone is like a macro stress arch. High stress is especially concentrated on both shoulders of the arch-shaped structure. The stress concentration of the solid zone in front of the gob is higher than the rear solid zone. (2) The characteristics of the vertical stress field in different regions are significantly different. Stress decreases in the zone above the gob and increases in solid zones on both sides of it. The mechanical analysis show that for a given stratum, the trajectories of principal stress are arch-shaped or inversely-arched, referred to as the “principal stress arch”, irrespective of its initial breaking or periodic breaking, and determines the fracture morphology. That is, the trajectories of tensile principal stress are inversely arched before the first breaking of the strata, and cause the breaking lines to resemble an inverted funnel. In case of periodic breaking, the breaking line forms an obtuse angle with the advancing direction of the panel. Good agreement was obtained between the results of physical modeling and the theoretical analysis.

The hydrogel sensor composited with MXene presents high stretchability, high sensitivity and high durability.

The anthracnose rot of postharvest mango fruit is a devastating fungal disease often resulting in tremendous quality deterioration and postharvest losses. Nitric oxide (NO), as an important signaling molecule, is involved in the responses to postharvest fruit diseases. In the present study, the effectiveness of NO donor sodium nitroprusside (SNP) to prevent anthracnose of “Tainong” mango fruit caused by Colletotrichum gloeosporioideswas evaluated through in vivo and in vitro tests. Results from in vivo test showed that SNP treatment effectively inhibited the lesion diameter and disease incidence on inoculated mango fruit during storage. SNP treatment could regulate hydrogen peroxide levels by reinforcing the activities of catalase, peroxidase, superoxide dismutase, and ascorbate peroxidase. Furthermore, SNP elevated the accumulation of lignin, total phenolics, anthocyanin, and flavonoids and the activities of chitinase and β-1,3-glucanase. In addition, in vitro tests indicated that SNP markedly suppressed mycelial growth and spore germination of C. gloeosporioidesthrough damaging plasma membrane integrity and increasing the leakage of soluble sugar and protein. Our results suggested that SNP could suppress anthracnose decay in postharvest mango fruit, possibly by directly suppressing pathogen growth and indirectly triggering host defense responses.

Recently, self-healing hydrogel bioelectronic devices have raised enormous interest for their tissue-like mechanical compliance, desirable biocompatibility, and tunable adhesiveness on bioartificial organs. However, the practical applications of these hydrogel-based sensors are generally limited by their poor fulfillment of stretchability and sensitivity, brittleness under subzero temperature, and single sensory function. Inspired by the fiber-reinforced microstructures and mechano-transduction systems of human muscles, a self-healing (90.8%), long-lasting thermal tolerant and dual-sensory hydrogel-based sensor is proposed, with high gauge factor (18.28) within broad strain range (268.9%), low limit of detection (5% strain), satisfactory thermosensation (−0.016 °C–1), and highly discernible temperature resolution (2.7 °C). Especially by introducing a glycerol/water binary solvent system, desirable subzero-temperature self-healing performance, high water-retaining, and durable adhesion feature can be achieved, resulting from the ice crystallization inhibition and highly dynamic bonding. On account of the advantageous mechanoreception and thermosensitive capacities, a flexible touch keyboard for signature identification and a “fever indicator” for human forehead’s temperature detection can be realized by this hydrogel bioelectronic device.

We investigated the effects of nitric oxide (NO) on quality, membrane lipid peroxidation, and antioxidant enzymes in mango (Mangifera indicaL. cv ‘Tainong’) fruit during ripening. Fruits were treated with 0.25 mmol·L-1sodium nitroprusside (SNP) by the immersion method and stored at 23°C for 20 days. SNP treatment significantly suppressed the respiration rate, enhanced fruit firmness, and decreased the rot index, peel color index, and weight loss in the fruit. This treatment also slowed the increase in soluble solids content (SSC) while maintaining high levels of titratable acidity (TA), ascorbic acid (AsA), and phenolic compounds. Furthermore, SNP treatment enhanced the antioxidant activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) and reduced the activities of lipoxygenase (LOX) and polyphenol oxidase (PPO) in mango fruit, which was associated with the reduced accumulation of malondialdehyde (MDA), superoxide anion radical (O2•-), and hydrogen peroxide (H2O2) compared with the control. Therefore, the addition of exogenous SNP has the potential for improving quality and prolonging the shelf life of mango fruits by protecting them against oxidative damage caused by ROS during ripening.

Cadmium Cd is a toxic heavymetal pollutant in the environment. Salicylic acid SA is an essential component of plant resistance to pathogens and also plays an important role in mediating plant responses to some abiotic stresses. In the present investigation, the potential effects of SA in alleviating Cd toxicity during seedling stage of rice were studied. Seeds of rice Oryza sativaL. cv. Xiushui 11 were sterilized and divided into two groups. Half of the seeds were presoaked in 0.1 mM SA solution for 24 h, then both groups were allowed to germinate under various Cd concentrations for 7 d. Cadmium treatments caused a gradual decrease in vigor index, root length, amylase activity, and the mitotic index of root tips. However, pretreatment with SA partially alleviated the negative effect of Cd on germination parameters and increased enzyme activity and mitotic index. Cadmium uptake by seedlings increased with increasing Cd concentration and followed MichaelisMenten kinetics. Salicylic acid pretreatment of seeds influenced the Cd level in the seedlings by decreasing Vmax. The results suggest that SA plays a positive role in riceseed germination and early seedling growth by protecting it against Cd toxicity.

In this study, zinc oxide nanoparticles (ZnO NPs) were synthesized using leaf extract of Cinnamomum camphora(L.) Presl and zinc acetate. Its antifungal activity was evaluated against Alternaria alternatawhich caused early blight disease in Solanum lycopersicum. The results showed that the size of the synthesized ZnO NPs obviously depended on the pH during the reaction. The peak of the UV–Vis spectra was at 368–374 nm, which confirmed the synthesis of ZnO NPs. SEM showed that the synthesized ZnO NPs agglomerated into spherical particles. TEM reveled that the average particle sizes of ZnO NPs synthesized at pH 7, pH 8 and pH 9 were about 13.92, 15.19 and 21.13 nm, respectively. Furthermore, ZnO NPs treatments at 20–160 mg/L could significantly inhibit the mycelia growth of A. alternata, and ZnO NPs synthesized at pH 7 showed the best antifungal effect with MIC value recorded as 20 mg/L. Moreover, 20 mg/L ZnO NPs synthesized at pH 7 significantly limited spore germination and germ tube elongation of A. alternata. In addition, ZnO NPs induced excessive accumulation of MDA in A. alternataand caused the damage of cell membrane, leading to the leakage of protein and nucleic acid. Therefore, green synthesized ZnO NPs, as a promising biocontrol agent, could be used to control fungal diseases.

Cadmium (Cd) contamination of paddy rice soils is commonly observed in the Yangtse River Delta, China. Large Cd uptake by rice plants and its translocation into the grains can entail human-health risks. Genotypic variations in Cd uptake and a differential Cd partitioning into grains will be the basis for developing a rice screening or breeding tool for low grain Cd. A field experiment, conducted at the experimental farm of Jiaxing, Zhejiang province from 2002 to 2004, compared 38 rice genotypes of different types (indica vs. japonica) collected from the Yangtse River Delta. The results showed large differences in Cd concentrations in straw, brown rice, and grain chaff among the rice genotypes grown on Cd-contaminated soil. Concentrations in brown rice ranged from 0.06 to 0.99 mg Cd kg–1. The total Cd uptake in brown rice varied between 0.96 and 28.58 μg plant–1. In general, indica-type cultivars accumulated significantly more Cd than the japonica-type cultivars. The Cd concentration in straw was highly correlated with that in brown rice. While significant differences in the Cd-partitioning ratio (% share of total Cd uptake found in brown rice) among rice genotypes were observed, these were not correlated with Cd concentration of brown rice. This indicates that the Cd accumulation in rice grains appears to be governed mainly by the Cd uptake by the plant and probably not by differential Cd partitioning. The large genotypic variation suggests the possibility to lower the Cd content of rice by genotype selection. The development of such breeding tools should focus on low Cd uptake rather than Cd partitioning between straw and grain.