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1.
Proc Natl Acad Sci U S A ; 121(3): e2312680121, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38194462

ABSTRACT

Periodic spin-orbit motion is ubiquitous in nature, observed from electrons orbiting nuclei to spinning planets orbiting the Sun. Achieving autonomous periodic orbiting motions, along circular and noncircular paths, in soft mobile robotics is crucial for adaptive and intelligent exploration of unknown environments-a grand challenge yet to be accomplished. Here, we report leveraging a closed-loop twisted ring topology with a defect for an autonomous soft robot capable of achieving periodic spin-orbiting motions with programmed circular and re-programmed irregular-shaped trajectories. Constructed by bonding a twisted liquid crystal elastomer ribbon into a closed-loop ring topology, the robot exhibits three coupled periodic self-motions in response to constant temperature or constant light sources: inside-out flipping, self-spinning around the ring center, and self-orbiting around a point outside the ring. The coupled spinning and orbiting motions share the same direction and period. The spinning or orbiting direction depends on the twisting chirality, while the orbital radius and period are determined by the twisted ring geometry and thermal actuation. The flip-spin and orbiting motions arise from the twisted ring topology and a bonding site defect that breaks the force symmetry, respectively. By utilizing the twisting-encoded autonomous flip-spin-orbit motions, we showcase the robot's potential for intelligently mapping the geometric boundaries of unknown confined spaces, including convex shapes like circles, squares, triangles, and pentagons and concaves shapes with multi-robots, as well as health monitoring of unknown confined spaces with boundary damages.

2.
Sci Adv ; 9(36): eadi3254, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37682998

ABSTRACT

Autonomous maze navigation is appealing yet challenging in soft robotics for exploring priori unknown unstructured environments, as it often requires human-like brain that integrates onboard power, sensors, and control for computational intelligence. Here, we report harnessing both geometric and materials intelligence in liquid crystal elastomer-based self-rolling robots for autonomous escaping from complex multichannel mazes without the need for human-like brain. The soft robot powered by environmental thermal energy has asymmetric geometry with hybrid twisted and helical shapes on two ends. Such geometric asymmetry enables built-in active and sustained self-turning capabilities, unlike its symmetric counterparts in either twisted or helical shapes that only demonstrate transient self-turning through untwisting. Combining self-snapping for motion reflection, it shows unique curved zigzag paths to avoid entrapment in its counterparts, which allows for successful self-escaping from various challenging mazes, including mazes on granular terrains, mazes with narrow gaps, and even mazes with in situ changing layouts.

3.
Waste Manag ; 169: 52-61, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37406504

ABSTRACT

Poor properties and high concentrations of heavy metals are still major concerns of successful application of animal manure-derived biochar into the environment. This work thus proposed to add chlorine-based additives (Cl-additives, i.e., CaCl2, MgCl2, KCl, NaCl, and PVC, 50 g Cl/ kg) to improve biochar properties and enhance heavy metal volatilization during swine manure pyrolysis. The results showed that the addition of CaCl2 could improve the retention of carbon (C) by up to 13.1% during pyrolysis, whereas other Cl-additives had little effect on it. Moreover, CaCl2 could enhance the aromaticity of biochar, as indicated by lower H/C ratio than raw biochar. Pretreatment with CaCl2, MgCl2 and PVC reduced phosphorus (P) solubility but increased its bioavailability via the formation of chlorapatite (Ca5(PO4)3Cl). The CaCl2 was more effective for enhancing the volatilization efficiency of heavy metals than other Cl-additives, except for Pb that tended to react with the generated Ca5(PO4)3Cl to form more stable and less volatile Pb5(PO4)3Cl. However, high pyrolysis temperature (900℃) was essential for CaCl2 to simultaneously decrease the bioavailability of heavy metals. Our results indicated that co-pyrolysis of swine manure with CaCl2 is a promising strategy to increase C retention, P bioavailability, and volatilization of heavy metals, and, at higher temperature, reduce the bioavailability of biochar-born heavy metals.


Subject(s)
Chlorine , Metals, Heavy , Swine , Animals , Manure , Pyrolysis , Calcium Chloride , Lead , Volatilization , Charcoal
4.
Ecotoxicol Environ Saf ; 251: 114528, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36640577

ABSTRACT

Perfluorooctanoic acid (PFOA) and arsenic are widely distributed pollutants and can coexist in the environment. However, no study has been reported about the effects of different arsenic species on the joint toxicity of arsenic and PFOA to soil invertebrates. In this study, four arsenic species were selected, including arsenite (As(III)), arsenate (As(V)), monomethylarsonate (MMA), and dimethylarsinate (DMA). Earthworms Eisenia fetida were exposed to soils spiked with sublethal concentrations of PFOA, different arsenic species, and their binary mixtures for 56 days. The bioaccumulation and biotransformation of pollutants, as well as eight biomarkers in organisms, were assayed. The results indicated that the coexistence of PFOA and different arsenic species in soils could enhance the bioavailability of arsenic species while reducing the bioavailability of PFOA, and inhibit the arsenic biotransformation process in earthworms. Responses of most biomarkers in joint treatments of PFOA and As(III)/As(V) showed more significant variations compared with those in single treatments, indicating higher toxicity to the earthworms. The Integrated Biomarker Response (IBR) index was used to integrate the multi-biomarker responses, and the results also exhibited enhanced toxic effects in combined treatments of inorganic arsenic and PFOA. In comparison, both the biomarker variations and IBR values were lower in joint treatments of PFOA and MMA/DMA. Then the toxic interactions in the binary mixture systems were characterized by using a combined method of IBR and Effect Addition Index. The results revealed that the toxic interactions of the PFOA/arsenic mixture in earthworms depended on the different species of arsenic. The combined exposure of PFOA with inorganic arsenic led to a synergistic interaction, while that with organic arsenic resulted in an antagonistic response. Overall, this study provides new insights into the assessment of the joint toxicity of perfluoroalkyl substances and arsenic in soil ecosystems.


Subject(s)
Arsenic , Arsenicals , Environmental Pollutants , Fluorocarbons , Oligochaeta , Soil Pollutants , Animals , Arsenic/analysis , Ecosystem , Arsenicals/metabolism , Fluorocarbons/toxicity , Fluorocarbons/metabolism , Cacodylic Acid/metabolism , Environmental Pollutants/metabolism , Biomarkers/metabolism , Soil , Soil Pollutants/analysis
5.
Environ Sci Technol ; 57(1): 231-243, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36525577

ABSTRACT

Nitrogen (N) deficiency in mining-contaminated habitats usually hinders plant growth and thus hampers tailing revegetation. Biological N fixation (BNF) is an essential biogeochemical process that contributes to the initial accumulation of N in oligotrophic mining-contaminated regions. Previous studies reported that chemolithotrophic rather than heterotrophic diazotrophs frequently dominated in the mining-contaminated regions. Chemolithotrophic diazotrophs may utilize elements abundant in such habitats (e.g., sulfur (S), arsenic (As), and antimony (Sb)) as electron donors to fix N2. BNF fueled by the oxidation of S and As has been detected in previous studies. However, BNF fueled by Sb(III) oxidation (Sb-dependent BNF) has never been reported. The current study observed the presence of Sb-dependent BNF in slurries inoculated from Sb-contaminated habitats across the South China Sb belt, suggesting that Sb-dependent BNF may be widespread in this region. DNA-stable isotope probing identified bacteria associated with Rhodocyclaceae and Rhizobiaceae as putative microorganisms responsible for Sb-dependent BNF. Furthermore, metagenomic-binning demonstrated that Rhodocyclaceae and Rhizobiaceae contained essential genes involved in Sb(III) oxidation, N2 fixation, and carbon fixation, suggesting their genetic potential for Sb-dependent BNF. In addition, meta-analysis indicated that these bacteria are widespread among Sb-contaminated habitats with different niche preferences: Rhodocyclaceae was enriched in river sediments and tailings, while Rhizobiaceae was enriched only in soils. This study may broaden our fundamental understanding of N fixation in Sb-mining regions.


Subject(s)
Arsenic , Nitrogen Fixation , Antimony/analysis , Antimony/chemistry , Oxidation-Reduction , Ecosystem , Nitrogen/analysis
6.
Adv Mater ; 35(7): e2207372, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36366927

ABSTRACT

Harnessing snapping, an instability phenomenon observed in nature (e.g., Venus flytraps), for autonomy has attracted growing interest in autonomous soft robots. However, achieving self-sustained snapping and snapping-driven autonomous motions in soft robots remains largely unexplored. Here, harnessing bistable, ribbon ring-like structures for realizing self-sustained snapping in a library of soft liquid-crystal elastomer wavy rings under constant thermal and photothermal actuation are reported. The self-sustained snapping induces continuous ring flipping that drives autonomous dancing or crawling motions on the ground and underwater. The 3D, free-standing wavy rings employ either a highly symmetric or symmetry-broken twisted shape with tunable geometric asymmetries. It is found that the former favors periodic self-dancing motion in place due to isotropic friction, while the latter shows a directional crawling motion along the predefined axis of symmetry during fabrication due to asymmetric friction. It shows that the crawling speed can be tuned by the geometric asymmetries with a peak speed achieved at the highest geometric asymmetry. Lastly, it is shown that the autonomous crawling ring can also adapt its body shape to pass through a confined space that is over 30% narrower than its body size.

7.
Environ Sci Pollut Res Int ; 30(2): 3997-4009, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35963968

ABSTRACT

Food processing of bean worm generates copious amount of skin as solid waste posing a serious environmental concern. The present study utilized bean worm skin (BWS) waste to produce KOH-modified biochars (KBWS-BCs) for the removal of sulfamethoxazole (SMX) from aqueous solution for the first time. Characterization of KBWS-BCs was systematically investigated via multiple instrumental analysis techniques. The sorption performance of KBWS-BCs as a function of solution pH, reaction time, initial SMX concentration, and reaction temperature was investigated using batch experiments. The classic kinetics and isotherm models were employed to fit the sorption data. KBWS-BCs exhibited large surface areas (3331-4742 m2 g-1) and ultrahigh sorption performance for SMX (maximum adsorption capacities of 909-2000 mg g-1), which were comparable to those of other modified biochars and even those of well-designed materials. Thermodynamic study indicated that the sorption of SMX on KBWS-BCs was a spontaneous (△G° < 0) and exothermic (△H° < 0) process. Mechanism analysis showed that both chemisorption and physisorption were responsible for the adsorption of SMX by KBWS-BCs. Overall, recycling BWS for preparation of high-performance biochars can be a "win-win" strategy for both disposal of BWS and removal of SMX from wastewater.


Subject(s)
Sulfamethoxazole , Water Pollutants, Chemical , Sulfamethoxazole/chemistry , Charcoal/chemistry , Potassium Compounds , Water Pollutants, Chemical/analysis , Adsorption
8.
J Hazard Mater ; 439: 129667, 2022 10 05.
Article in English | MEDLINE | ID: mdl-36104899

ABSTRACT

Perfluorohexanesulfonic acid (PFHxS) is one of the persistent organic pollutants that has been recommended to be listed in Annex A of the Stockholm Convention. It has gained increasing attention in recent years due to its toxic effects. The guideline values of PFHxS are commonly associated with PFOS in various countries and regulatory agencies. In this study, multispecies bioassays were conducted to determine the ecological toxic effects of PFHxS, including plants, soil invertebrates, and soil microorganisms, which indicated the EC10/NOEC values ranged from 2.9 to 250 mg/kg. Where possible, logistic models were used to calculate the EC30 values for various endpoints. The species sensitivity distributions were employed to estimate the ecological investigation levels for PFHxS contamination in soils using toxicity results from literature and this study. The calculation using EC10/NOEC values from both literature and this study indicated a most conservative HC5 as 1.0 mg/kg (hazardous concentration for 5 % of the species being impacted). However, utilisation of EC30 values derived from this study resulted in a much higher HC5 for PFHxS in contaminated soils (13.0 mg/kg) which is at the higher end of the existing guideline values for PFOS for protecting ecological systems. The results obtained in this study can be useful in risk assessment processes to minimize any uncertainty using combined values with PFOS.


Subject(s)
Soil Pollutants , Soil , Animals , Fluorocarbons , Invertebrates , Risk Assessment , Soil Pollutants/analysis , Soil Pollutants/toxicity , Sulfonic Acids
9.
Environ Sci Pollut Res Int ; 29(28): 42102-42116, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35366209

ABSTRACT

This paper summarises a study of the application of the synthetic chelate ethylenediaminetetraacetic acid (EDTA), and the natural chelates ethylenediamine-N,N'-disuccinic acid (EDDS) and nitrilotriacetate (NTA) to enhance ryegrass (Lolium multiflorum Lam.) uptake of the heavy metal(oid)s (HMs) (As, Cd, Cu, Pb and Zn) from contaminated soils in mining sites. The study compares the effects of these chelates (EDTA, EDDS and NTA) on the phytoavailability of HMs (As, Cd, Cu, Pb, Zn) using ryegrass (Lolium multiflorum Lam.) through the single addition and sequential addition methods. The results show that application of EDTA, EDDS and NTA significantly increases ryegrass (Lolium multiflorum Lam.)'s shoot uptake of some HMs when compared with no EDTA, EDDS or NTA application, particularly through sequential chelate treatment (EDTA 0.5:1+0.5:1; NTA 0.5:1+0.5:1; EDDS 0.5:1+0.5:1). EDTA 0.5:1+0.5:1 was more effective at increasing the concentration of Pb in shoots than were the other chelates (EDDS and NTA) and controls. Moreover, the concentrations of Zn in the shoots of ryegrass (Lolium multiflorum Lam.) in Hich Village significantly increased with the application of split dose (0.5:1+0.5:1). The plants displayed symptoms of toxicity including yellow and necrotic leaves at the end of the experiment. The selected chelates (EDTA, EDDS and NTA) led to a significant decrease in plant biomass (yield) 28 days after transfer with a maximum decrease in EDTA treatment (0.5:1+0.5:1) soils. This decrease was 3.43-fold in Ha Thuong, 3-fold in Hich Village and 1.59-fold in Trai Cau, respectively, relative to the control. HM concentration and dissolved organic carbon (DOC) in pore water provided an explanation for why fresh weight was significantly reduced with application of chelates in sequential dose (EDTA 0.5:1+0.5:1 and NTA 0.5:1+0.5:1).


Subject(s)
Lolium , Metals, Heavy , Soil Pollutants , Biodegradation, Environmental , Cadmium , Chelating Agents/pharmacology , Edetic Acid/pharmacology , Ethylenediamines/pharmacology , Lead , Metals, Heavy/analysis , Soil , Soil Pollutants/analysis , Succinates , Zinc
10.
Int J Biol Macromol ; 207: 826-840, 2022 May 15.
Article in English | MEDLINE | ID: mdl-35358575

ABSTRACT

Mesoporous (~7-8 nm) biopolymer hydrogel beads (HNTs-FeNPs@Alg/ß-CD) were synthesised via ionic polymerisation route to separate heavy metal ions. The adsorption capacity of HNTs-FeNPs@Alg/ß-CD was higher than that of raw halloysite nano tubes (HNTs), iron nanoparticles (FeNPs), and bare alginate beads. FeNPs induce the magnetic properties of adsorbent and metal-based functional groups in and around the hydrogel beads. The mesoporous surface of the adsorbent permits access of heavy metal ions onto the polymer beads to interact with internal active sites and the mesoporous polymer network. Maximum adsorption capacities of lead (Pb), copper (Cu), cadmium (Cd), and nickel (Ni) were 21.09 mg/g, 15.54 mg/g, 2.47 mg/g, and 2.68 mg/g, respectively. HNTs-FeNPs@Alg/ß-CD was able to adsorb heavy metals efficiently (75-99%) under environment-relevant concentrations (200 µg/L) from mixed metal contaminants. The adsorption and selectivity trends of heavy metals were Pb > Cu > Cd > Ni, despite electrostatic binding strength of Cd > Cu > Pb > Ni and covalent binding strength of Pb > Ni > Cu > Cd. It demonstrated that not only chemosorption but also physisorption acts as the sorption mechanism. The reduction in surface area, porosity, and pore volume of the expended adsorbent, along with sorption study results, confirmed that pore filling and intra-particle diffusion played a considerable role in removing heavy metals.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Adsorption , Alginates/chemistry , Cadmium , Cellulose , Cyclodextrins , Hydrogels , Hydrogen-Ion Concentration , Ions , Kinetics , Lead , Magnetic Phenomena , Nickel , Polymers
11.
Sci Total Environ ; 824: 153963, 2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35183629

ABSTRACT

Microplastics can be found almost everywhere, including in our kitchens. The challenge is how to characterise them, particularly for the small ones (<1 µm), referred to as nanoplastics, when they are mixed with larger particles and other components. Herewith we advance Raman imaging to characterise microplastics and nanoplastics released from a dish sponge that we use every day to clean our cookware and eating utensils. The scanning electron microscopy result shows significantly different structures of the soft and hard layers of the sponge, with the hard layer being more likely to shed particles. By scanning the sample surface to generate a spectrum matrix, Raman imaging can significantly improve signal-noise-ratio, compared with individual Raman spectra. Through mapping the characteristic peaks from the matrix that contains hundreds, even thousands of Raman spectra, it is confirmed that the particles released from the soft and hard layers of the sponge are mainly Nylon PA6 and polyethylene terephthalate, respectively. Using principal component analysis (PCA) to decode the spectrum matrix further enhances the signal-noise ratio, which enables mapping the whole set of the spectrum, rather than the selected peaks. By optimising the Raman scanning parameters, the PCA-Raman imaging is able to reliably capture and visualise microplastics and nanoplastics released from both sides of the dish sponge, including a plastic-surrounding-sand composite structure. Overall, PCA-Raman imaging is a holistic and effective approach to characterising miniature plastic particles.


Subject(s)
Microplastics , Water Pollutants, Chemical , Multivariate Analysis , Plastics , Principal Component Analysis , Spectrum Analysis, Raman , Water Pollutants, Chemical/analysis
12.
Nat Commun ; 13(1): 918, 2022 02 17.
Article in English | MEDLINE | ID: mdl-35177598

ABSTRACT

While vat photopolymerization has many advantages over soft lithography in fabricating microfluidic devices, including efficiency and shape complexity, it has difficulty achieving well-controlled micrometer-sized (smaller than 100 µm) channels in the layer building direction. The considerable light penetration depth of transparent resin leads to over-curing that inevitably cures the residual resin inside flow channels, causing clogs. In this paper, a 3D printing process - in-situ transfer vat photopolymerization is reported to solve this critical over-curing issue in fabricating microfluidic devices. We demonstrate microchannels with high Z-resolution (within 10 µm level) and high accuracy (within 2 µm level) using a general method with no requirements on liquid resins such as reduced transparency nor leads to a reduced fabrication speed. Compared with all other vat photopolymerization-based techniques specialized for microfluidic channel fabrication, our universal approach is compatible with commonly used 405 nm light sources and commercial photocurable resins. The process has been verified by multifunctional devices, including 3D serpentine microfluidic channels, microfluidic valves, and particle sorting devices. This work solves a critical barrier in 3D printing microfluidic channels using the high-speed vat photopolymerization process and broadens the material options. It also significantly advances vat photopolymerization's use in applications requiring small gaps with high accuracy in the Z-direction.

13.
Chemosphere ; 291(Pt 2): 132942, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34793848

ABSTRACT

Perfluorooctanoic acid (PFOA) and arsenic are ubiquitous environmental contaminants and could co-exist in soil. However, data on their possible combined toxic effects on terrestrial organisms are still lacking. In this study, we exposed earthworm Eisenia fetida to artificial soil spiked with different sub-lethal levels of PFOA, arsenite (As(III)) or their mixture for 28 days. The bioaccumulation and multi-biomarker responses in the earthworms were measured. Results showed that the co-existence of PFOA and As(III) in soil enhanced the bioaccumulation of arsenic while reduced the bioaccumulation of PFOA. Most selected biomarkers exhibited significant responses at higher exposure levels and indicated oxidative damages. Biomarker Response Index (BRI) was used to integrate the multi-biomarker responses and the results showed significant dose-effect relationships between biological health status and exposure levels. Moreover, variation analysis of multi-biomarkers and BRI proved that As(III) exhibited more toxicity than PFOA to the earthworms. Based on BRI results, Effect Addition Index (EAI) was calculated to evaluate the joint effects of the two toxicants. According to EAI, the joint toxicity of PFOA and As(III) was related to exposure concentration, changing from synergism to slight antagonism with the increase of exposure level. These results provide valuable toxicological information for the risk assessment of co-exposure to PFOA and arsenic in the soil environment. Moreover, this study proved that BRI is an effective tool to integrate multi-biomarker responses, and its combination with EAI provides a useful combined approach to evaluate the joint effects of mixed contamination systems.


Subject(s)
Arsenites , Oligochaeta , Soil Pollutants , Animals , Arsenites/toxicity , Biomarkers , Caprylates , Fluorocarbons , Soil , Soil Pollutants/analysis , Soil Pollutants/toxicity
14.
Adv Mater ; 33(44): e2104251, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34480501

ABSTRACT

Ultrasound energy transfer (UET) is developed and integrated into various bioelectronics with diagnostic, therapeutic, and monitoring capabilities. However, existing UET platforms generally enable one function at a time due to the single ultrasound channel architecture, limiting the full potential of bioelectronics that requires multicontrol modes. Here, a multichannel piezo-ultrasound implant (MC-PUI) is presented that integrates a hybrid waterborne acoustic metastructure (HWAM), multiple piezo-harvesters, and a miniaturized circuit with electronic components for selective wireless control via ultrasound frequency switching. The HWAM that utilizes both a 3D-printed air-diffraction matrix and a half-lambda Fabry-Perot resonator is optimized to provide the advantage of ultrasound selectivity at megahertz frequencies. Complying with U.S. Food and Drug Administration regulations, frequency-controlled multifunctional operations, such as wireless charging (≈11.08 µW) at 3.3 MHz and high-sensitivity wireless switch/control (threshold ≈0.55 MPa) of micro-light-emitting diode/motor at 1 MHz, are demonstrated ex vivo using porcine tissue and in vivo in a rat. The developed MC-PUI enhances UET versatility and opens up a new pathway for wireless implant design.


Subject(s)
Ultrasonography
15.
PLoS One ; 16(7): e0255229, 2021.
Article in English | MEDLINE | ID: mdl-34314442

ABSTRACT

This study is to assess the influences of climate, socio-economic determinants, and spatial distance on the confirmed cases and deaths in the raise phase of COVID-19 in China. The positive confirmed cases and deaths of COVID-19 over the population size of 100,000 over every 5 consecutive days (the CCOPSPTT and DOPSPTT for short, respectively) covered from 25th January to 29th February, 2020 in five city types (i.e., small-, medium-, large-, very large- and super large-sized cities), along with the data of climate, socio-economic determinants, spatial distance of the target city to Wuhan city (DW, for short), and spatial distance between the target city and their local province capital city (DLPC, for short) were collected from the official websites of China. Then the above-mentioned influencing factors on CCOPSPTT and DOPSPTT were analyzed separately in Hubei and other provinces. The results showed that CCOPSPTT and DOPSPTT were significantly different among five city types outside Hubei province (p < 0.05), but not obviously different in Hubei province (p > 0.05). The CCOPSPTT had significant correlation with socio-economic determinants (GDP and population), DW, climate and time after the outbreak of COVID-19 outside Hubei province (p < 0.05), while was only significantly related with GDP in Hubei province (p < 0.05). The DOPSPTT showed significant correlation with socio-economic determinants, DW, time and CCOPSPTT outside Hubei province (p < 0.05), while was significantly correlated with GDP and CCOPSPTT in Hubei province (p < 0.05). Compared with other factors, socio-economic determinants have the largest relative contribution to variance of CCOPSPTT in all studied cities (> 78%). The difference of DOPSPTT among cities was mainly affected by CCOPSPTT. Our results showed that influences of city types on the confirmed cases and death differed between Hubei and other provinces. Socio-economic determinants, especially GDP, have higher impact on the change of COVID-19 transmission compared with other factors.


Subject(s)
COVID-19/epidemiology , Climate , Socioeconomic Factors , COVID-19/mortality , China/epidemiology , Cities/epidemiology , Disease Outbreaks , Humans , Spatial Analysis
16.
ACS Omega ; 6(23): 15316-15331, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34151111

ABSTRACT

Halloysite nanotubes (HNT) and ball-milled biochar (BC) incorporated biocompatible mesoporous adsorbents (HNT-BC@Alg) were synthesized for adsorption of aqueous heavy-metal ions. HNT-BC@Alg outperformed the BC, HNT, and BC@Alg in removing cadmium (Cd), copper (Cu), nickel (Ni), and lead (Pb). Mesoporous structure (∼7.19 to 7.56 nm) of HNT-BC@Alg was developed containing an abundance of functional groups induced from encapsulated BC and tubular HNT, which allowed heavy metals to infiltrate and interact with the adsorbents. Siloxane groups from HNT, oxygen-containing functional groups from BC, and hydroxyl and carboxyl groups from alginate polymer play a significant role in the adsorption of heavy-metal ions. The removal percentage of heavy metals was recorded as Pb (∼99.97 to 99.05%) > Cu (∼95.01 to 90.53%) > Cd (∼92.5 to 55.25%) > Ni (∼80.85 to 50.6%), even in the presence of 0.01/0.001 M of CaCl2 and Na2SO4 as background electrolytes and charged organic molecule under an environmentally relevant concentration (200 µg/L). The maximum adsorption capacities of Ni, Cd, Cu, and Pb were calculated as 2.85 ± 0.08, 6.96 ± 0.31, 16.87 ± 1.50, and 26.49 ± 2.04 mg/g, respectively. HNT-BC@Alg has fast sorption kinetics and maximum adsorption capacity within a short contact time (∼2 h). Energy-dispersive X-ray spectroscopy (EDS) elemental mapping exhibited that adsorbed heavy metals co-distributed with Ca, Si, and Al. The reduction of surface area, pore volume, and pore area of HNT-BC@Alg (after sorption of heavy metals) confirms that mesoporous surface (2-18 nm) supports diffusion, infiltration, and interaction. However, a lower range of mesoporous diameter of the adsorbent is more suitable for the adsorption of heavy-metal ions. The adsorption isotherm and kinetics fitted well with the Langmuir isotherm and the pseudo-second-order kinetic models, demonstrating the monolayer formation of heavy-metal ions through both the physical sorption and chemical sorption, including pore filling, ion exchange, and electrostatic interaction.

17.
Sci Total Environ ; 781: 146745, 2021 Aug 10.
Article in English | MEDLINE | ID: mdl-33794456

ABSTRACT

Tetrabromobisphenol A (TBBPA) is a type of brominated flame retardant widely detected in the environment and organisms. It has been reported to cause cytotoxicity and disrupt endocrine system of animals. However, the effect of TBBPA on the reproductive system of male rodents is still controversial. Hence, this meta-analysis aims to determine whether TBBPA exposure damage to the reproductive system of male rodents. In this study, a thorough search of literatures was undertaken to select papers published before December 1st, 2020. The standard mean difference (SMD) and 95% confidence interval (CI) were calculated by random model. The results showed a statistically significant association between TBBPA exposure and the reproductive system health of male rodents (SMD = -0.35, 95% CI -0.50 to -0.19). The SMD for the reproductive system index organ weight, sperm quality, hormone levels, and gene expression were 0.03 (95% CI -0.18 to 0.23), -0.47 (95% CI -0.78 to -0.16), -0.51 (95% CI -0.75 to -0.27), and -0.98 (95% CI -1.36 to -0.60), respectively. There was a significant dose-effect relationship between TBBPA exposure and the reproductive health of male rodents, with the SMD values of low, medium, and high doses -0.20 (95% CI -0.34 to -0.05), -0.24 (95% CI -0.56 to 0.07), and -0.48 (95% CI -0.83 to -0.13), respectively. For exposure duration of TBBPA, an exposure time of >10 weeks (SMD = -0.33, 95% CI -0.54 to -0.12) showed more significant effect than an exposure time of ≤10 weeks (SMD = -0.22, 95% CI -0.43 to -0.02). Moreover, TBBPA exposure exhibited significant negative effects on sperm count (SMD = -0.49, 95% CI -0.82 to -0.17) while also reduced the content of triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) hormones. To summarize, our meta-analysis indicated that TBBPA had a toxicity effect to the reproductive system of male rodents.


Subject(s)
Flame Retardants , Polybrominated Biphenyls , Animals , Flame Retardants/toxicity , Male , Polybrominated Biphenyls/toxicity , Reproductive Health , Rodentia
18.
Int J Biol Sci ; 16(14): 2675-2691, 2020.
Article in English | MEDLINE | ID: mdl-32792864

ABSTRACT

Bone metabolic disorders include osteolysis, osteoporosis, osteoarthritis and rheumatoid arthritis. Osteoblasts and osteoclasts are two major types of cells in bone constituting homeostasis. The imbalance between bone formation by osteoblasts and bone resorption by osteoclasts has been shown to have a direct contribution to the onset of these diseases. Recent evidence indicates that autophagy and mitophagy, the selective autophagy of mitochondria, may play a vital role in regulating the proliferation, differentiation and function of osteoblasts and osteoclasts. Several signaling pathways, including PINK1/Parkin, SIRT1, MAPK8/FOXO3, Beclin-1/BECN1, p62/SQSTM1, and mTOR pathways, have been implied in the regulation of autophagy and mitophagy in these cells. Here we review the current progress about the regulation of autophagy and mitophagy in osteoblasts and osteoclasts in these bone metabolic disorders, as well as the molecular signaling activated or deactivated during this process. Together, we hope to draw attention to the role of autophagy and mitophagy in bone metabolic disorders, and their potential as a new target for the treatment of bone metabolic diseases and the requirements of further mechanism studies.


Subject(s)
Mitophagy , Osteoarthritis/etiology , Osteolysis/etiology , Osteoporosis/etiology , Signal Transduction , Animals , Arthritis, Rheumatoid/etiology , Humans , Osteoblasts/metabolism , Osteoclasts/metabolism
19.
Sci Total Environ ; 744: 140714, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-32717463

ABSTRACT

Biochar is a porous, amorphous, stable, and low-density carbon material derived from the carbonization of various biological residues. Biochars have multifunctional properties that make them promising adsorbents for the remediation of organic and inorganic contaminants from soil and water. High temperature treatment (HTT) and the properties of feedstocks are key factors influencing the properties of biochars. Feedstocks have distinctive physicochemical properties due to variations in elemental and structural composition, and they respond heterogeneously to specific pyrolysis conditions. The criteria for the selection of feedstocks and pyrolysis conditions for designing biochars for specific sorption properties are inadequately understood. We evaluated the influence of pyrolysis temperature on a wide range of feedstocks to investigate their effects on biochar properties. With increasing HTT, biochar pH, surface area, pore size, ash content, hydrophobicity and O/C vs. H/C (ratios that denote stability) increased, whereas, hydrophilicity, yield of biochar, O/C, and H/C decreased. Discriminant analysis of data from 533 published datasets revealed that biochar derived from hardwood (HBC) and softwood generally have greater surface area and carbon content, but lower content of oxygen and mineral constituents, than manure- (MBC) and grass-derived biochars (GBC). GBC and MBC have abundant oxygen-containing functional groups than SBC and HBC. The sequence of stability and aromaticity of feedstocks was MBC < GBC < SBC < HBC. Therefore, SBC and HBC are suitable for sorption of hydrophobic molecules. Biochars produced from low HTT are suitable for removal of ionic contaminants, whereas those produced at high HTT are suitable for removal of organic contaminants. The influences of biochar properties on sorption performance of heavy metals and organic contaminants are critically reviewed.


Subject(s)
Charcoal , Pyrolysis , Adsorption , Manure , Temperature
20.
Ann Transl Med ; 8(4): 131, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32175424

ABSTRACT

There is a high risk of injury from damage to the force-bearing tissue of the tendon. Due to its poor self-healing ability, clinical interventions for tendon injuries are limited and yield unsatisfying results. Tissue engineering might supply an alternative to this obstacle. As one of the key elements of tissue engineering, various cell sources have been used for tendon engineering, but there is no consensue concerning a single optimal source. In this review, we summarized the development of tendon tissue from the embryonic stage and categorized the used cell sources in tendon engineering. By comparing various cell sources as the candidates for tendon regeneration, each cell type was found to have its advantages and limitations; therefore, it is difficult to define the best cell source for tendon engineering. The microenvironment cells located is also crucial for cell growth and differentiation; so, the optimal cells are unlikely to be the same for each patient. In the future, the clinical application of tendon engineering might be more precise and customized in contrast to the current use of a standardized/generic one-size-fits-all procedure. The best cell source for tendon engineering will require a case-based assessment.

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