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1.
Chemistry ; 30(19): e202304081, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38288909

RESUMEN

Optically pure sulfoxides are valuable organosulfur compounds extensively employed in medicinal and organic synthesis. In this study, we present a biocatalytic oxidation-reduction cascade system designed for the preparation of enantiopure sulfoxides. The system involves the cooperation of a low-enantioselective chimeric oxidase SMO (styrene monooxygenase) with a high-enantioselective reductase MsrA (methionine sulfoxide reductase A), facilitating "non-selective oxidation and selective reduction" cycles for prochiral sulfide oxidation. The regeneration of requisite cofactors for MsrA and SMO was achieved via a cascade catalysis process involving three auxiliary enzymes, sustained by cost-effective D-glucose. Under the optimal reaction conditions, a series of heteroaryl alkyl, aryl alkyl and dialkyl sulfoxides in R configuration were synthesized through this "one-pot, one step" cascade reaction. The obtained compounds exhibited high yields of >90 % and demonstrated enantiomeric excess (ee) values exceeding 90 %. This study represents an unconventional and efficient biocatalytic way in utilizing the low-enantioselective oxidase for the synthesis of enantiopure sulfoxides.


Asunto(s)
Metionina Sulfóxido Reductasas , Sulfóxidos , Biocatálisis , Oxidación-Reducción , Catálisis , Estereoisomerismo
2.
J Am Chem Soc ; 145(22): 12360-12369, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37226400

RESUMEN

Hybrid metal halides (HMHs) are a class of materials that combine extraordinary photophysical properties and excellent processability. Their chemical variability allows for the solid-liquid transition toward melt-processable HMHs. Herein, we report the design and synthesis of zero-dimensional HMHs [M(DMSO)6][SbCl6], where the isolated octahedra of [M(DMSO)6]3+ and [SbCl6]3- are alternatively aligned in the crystal structure. The luminescent center of [SbCl6]3- enables the photogeneration of self-trapped excitons, resulting in broadband photoluminescence with a large Stokes shift and a nearly 100% quantum yield. Meanwhile, the release of DMSO ligands from [M(DMSO)6]3+ is controlled by the M-O coordination and thus a low melting point of ∼90 °C is achieved for HMHs. Interestingly, the glass phase is obtained by melt quenching, with a sharp change in photoluminescence colors compared to the crystal phase of melt-processable HMHs. The robust crystal-liquid-glass transition opens a new avenue to tailoring structural disorder and optoelectronic performance in organic-inorganic materials.

3.
Cancer Immunol Immunother ; 72(10): 3163-3174, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37382633

RESUMEN

BACKGROUND: Chimeric antigen receptor-modified T cells (CAR T-cells) have shown exhilarative clinical efficacy for hematological malignancies. However, a shared antigen pool between healthy and malignant T-cells remains a concept to be technically and clinically explored for CAR T-cell therapy in T-cell cancers. No guidelines for engineering CAR T-cells targeting self-expressed antigens are currently available. METHOD: Based on anti-CD70 CAR (CAR-70) T-cells, we constructed CD70 knock-out and wild-type CAR (CAR-70KO and CAR-70WT) T-cells and evaluated their manufacturing and anti-tumor capability. Single-cell RNA sequencing and TCR sequencing were performed to further reveal the underlying differences between the two groups of CAR T-cells. RESULTS: Our data showed that the disruption of target genes in T-cells before CAR transduction advantaged the expansion and cell viability of CAR T-cells during manufacturing periods, as well as the degranulation, anti-tumor efficacy, and proliferation potency in response to tumor cells. Meanwhile, more naïve and central memory phenotype CAR+ T-cells, with higher TCR clonal diversity, remained in the final products in KO samples. Gene expression profiles revealed a higher activation and exhaustion level of CAR-70WT T-cells, while signaling transduction pathway analysis identified a higher level of the phosphorylation-related pathway in CAR-70KO T-cells. CONCLUSION: This study evidenced that CD70 stimulation during manufacturing process induced early exhaustion of CAR-70 T-cells. Knocking-out CD70 in T-cells prevented the exhaustion and led to a better-quality CAR-70 T-cell product. Our research will contribute to good engineering CAR T-cells targeting self-expressed antigens.


Asunto(s)
Receptores Quiméricos de Antígenos , Transcriptoma , Línea Celular Tumoral , Linfocitos T , Inmunoterapia Adoptiva , Receptores de Antígenos de Linfocitos T/genética
4.
Org Biomol Chem ; 21(16): 3417-3422, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37017279

RESUMEN

Optically pure sulfoxides are noteworthy compounds that find wide applications in various industrial fields. Here, we report a methionine sulfoxide reductase B (MsrB) homologue that exhibits high enantioselectivity and broad substrate scope for the kinetic resolution of racemic (rac) sulfoxides. This MsrB homologue, named liMsrB, was identified from Limnohabitans sp. 103DPR2 and showed good activity together with enantioselectivity towards a series of aromatic, heteroaromatic, alkyl and thioalkyl sulfoxides. Chiral sulfoxides in the S configuration were prepared in approximately 50% yield and 92-99% enantiomeric excess through kinetic resolution at an initial substrate concentration of up to 90 mM (11.2 g L-1). This study presents an efficient route for the enzymatic preparation of (S)-sulfoxides through kinetic resolution.


Asunto(s)
Metionina Sulfóxido Reductasas , Sulfóxidos , Sulfóxidos/química , Cinética , Estereoisomerismo , Metionina
5.
Environ Geochem Health ; 45(8): 6675-6692, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37354254

RESUMEN

Determining the geochemical background for heavy metals is vital in soil management activities. Although many statistical methods for geochemical background determination have been proposed, the multi-population problem of geochemical data, primarily regional ones, derived mainly from mixing multiple populations belonging to various geological sources or processes, needs to be better addressed. In this study, the Expectation-Maximization (EM) algorithm was employed to separate multiple populations in a 1:250,000 scale regional geochemical data set of soils in a lithologically complex region in the north of Changchun, China. The data set included 3746 surface soil samples analyzed for SiO2, K2O, Al2O3, CaO, La, Rb, Y, Ti, Ce, V, Cr, and As. The potential high-risk areas of As and Cr were determined before and after the separation of multiple populations. The comparison results show that the EM clustering method can efficiently separate multiple populations and determine soil geochemical background more reasonably, thus eliminating false contamination that is easily misidentified and better revealing concealed contamination that is challenging to detect.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Suelo , Dióxido de Silicio , Contaminantes del Suelo/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Análisis por Conglomerados , China , Medición de Riesgo
6.
Biochem Cell Biol ; 100(1): 9-16, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34658256

RESUMEN

Cardiovascular and related metabolic diseases are significant global health challenges. Glucagon-like peptide 1 (GLP-1) is a brain-gut peptide secreted by the ileal endocrine system and is now an established drug target in type 2 diabetes (T2DM). GLP-1 targeting agents have been shown not only to treat T2DM, but also to exert cardiovascular protective effects by regulating multiple signaling pathways. The mitogen-activated protein kinase (MAPK) pathway, a common signal transduction pathway for transmitting extracellular signals to downstream effector molecules, is involved in regulating diverse cellular physiological processes, including cell proliferation, differentiation, stress, inflammation, functional synchronization, transformation, and apoptosis. The purpose of this review is to highlight the relationship between GLP-1 and cardiovascular disease (CVD) and discuss how GLP-1 exerts cardiovascular protective effects through the MAPK signaling pathway. This review also discusses the future challenges in fully characterizing and evaluating the CVD protective effects of GLP-1 receptor agonists (GLP-1RA) at the cellular and molecular levels. A better understanding of the MAPK signaling pathway that is dysregulated in CVD may aid in the design and development of promising GLP-1RA.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Receptor del Péptido 1 Similar al Glucagón/uso terapéutico , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Transducción de Señal
7.
Dig Dis Sci ; 67(6): 2173-2181, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34097168

RESUMEN

BACKGROUND: Colon cancer, ranked third in cancer related mortality, is the most common malignant cancer of digestive tract. Though immune checkpoint inhibitors show promising efficacy in colon cancer, a rather high unresponsive rate and recurrence rate requires further elucidation of the underlying regulatory mechanism of cancer-related immunity. AIMS: To study the regulatory function of Orexin A in the expression of exosomal PD-L1 and T cell activity. METHODS: Orthotopic colon cancer transplantation mice model were established to study the cancer growth and immune infiltration between Orexin A treated group and untreated group. In vitro studies using mouse CT-26 and human HCT-116 colon cancer cell model studied the effect of Orexin A on cellular and exosomal PD-L1 expression. Co-culturing Jurkat cells with exosomes delivered by cancer cells treated with Orexin A, PD-L1 knockdown and PBS studied different effects on T cell. Comparing Orexin A with WP1066, a JAK2/STAT3 inhibitor verified the mechanism of these changes. RESULTS: The growth rate of orthotopic transplanted colon cancer was slower in Orexin A treated group, with lower PD-L1 expression and higher immune infiltration. Orexin A could inhibit cellular and exosomal PD-L1 expression. The decreased expression of PD-L1 in exosomes could promote the activity of Jurkat cells secreting higher level of IFN-γ and IL-2. Orexin A showed a similar effect like WP1066 which proved JAK2/STAT3 signaling pathway was its downstream signaling pathway. CONCLUSIONS: Orexin A could suppress the expression of exosomal PD-L1 in colon cancer cells and promote T cells activity by inhibiting JAK2/STAT3 signaling pathway.


Asunto(s)
Antígeno B7-H1 , Neoplasias del Colon , Animales , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Humanos , Janus Quinasa 2/metabolismo , Ratones , Orexinas/metabolismo , Orexinas/farmacología , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Linfocitos T
8.
Angew Chem Int Ed Engl ; 61(37): e202209272, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35831972

RESUMEN

Optically pure sulfoxides are noteworthy compounds applied in a wide range of industrial fields; however, the biocatalytic deracemization of racemic sulfoxides is challenging. Herein, a high-enantioselective methionine sulfoxide reductase A (MsrA) was combined with a low-enantioselective styrene monooxygenase (SMO) for the cyclic deracemization of sulfoxides. Enantiopure sulfoxides were obtained in >90 % yield and with >90 % enantiomeric excess (ee) through dynamic "selective reduction and non-selective oxidation" cycles. The cofactors of MsrA and SMO were subsequently regenerated by the cascade catalysis of three auxiliary enzymes through the consumption of low-cost D-glucose. Moreover, this "one-pot, one-step" cyclic deracemization strategy exhibited a wide substrate scope toward various aromatic, heteroaromatic, alkyl and thio-alkyl sulfoxides. This system proposed an efficient strategy for the green synthesis of chiral sulfoxide.


Asunto(s)
Metionina Sulfóxido Reductasas , Sulfóxidos , Catálisis , Oxidación-Reducción , Regeneración , Estereoisomerismo , Sulfóxidos/química
9.
J Am Chem Soc ; 143(22): 8437-8445, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34000194

RESUMEN

Structural engineering in multiple scales permits the integration of exotic properties into a single material, which boosts the development of ultracompact multifunctional devices. Layered perovskites are capable of cross-linking efficient carrier transport originating from few-layer perovskite frameworks with extended functionalities contributed by designable bulky organic cations and nanostructures, thus providing a platform for multiscale material engineering. Herein, high-performance Stokes-parameter photodetectors for arbitrary polarized light detection are realized on the basis of solution-processed chiral-perovskite nanowire arrays. The chiral ammonium cations intercalated between the perovskite layers are responsive to circularly polarized light with a maximum anisotropy factor of 0.15, while the strictly aligned nanowires with the anisotropic dielectric function result in a large polarized ratio of 1.6 to linearly polarized light. Single crystallinity and pure crystallographic orientation permit efficient in-plane carrier transport along the nanowires, yielding a responsivity of 47.1 A W-1 and a detectivity of 1.24 × 1013 Jones. By synergy of linear- and circular-polarization response with high optoelectronic performance for providing sufficient photocurrent contrasts, Stokes-parameter photodetection is demonstrated on these nanowires. Our Stokes-parameter photodetectors with a small footprint and high performances present promising applications toward polarization imaging.

10.
Small ; 17(21): e2100332, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33864427

RESUMEN

Optoelectronic applications of organic semiconductors demand single-crystalline structures with long-range order and suppressed defects for sustaining efficient carrier transport and long photocarrier lifetime, which are pivotal in photodetection, photovoltaic, and light emission. For integrated devices, an additional requirement of precise patterning is imposed, whereas the patterning of single-crystalline organic microstructures is still challenging because the molecular stacking is easily perturbed by disordered fluids in microdroplets. Herein, a capillary-bridge lithography is developed for driving the directional transport of capillary flows to control the confined crystallization of organic 1D single-crystalline arrays with aligned positioning and pure orientation. Through tuning the concentration and pressure, the size of organic 1D arrays in three dimensions can be controlled with 2.9-5.8 µm in width and 1.2 µm to 110 nm in height. Organic 1D array photodetectors exhibit a stable performance with on/off ratio of 180 and responsivity of 4.99 mA W-1 . Based on the scalable fabrication of 1D array photodetectors, 20 × 20 multiplexed image sensors with high accuracy are demonstrated for capturing the light signals of capital letter "A," "B," and "C." This research will open opportunities for the large-scale fabrication of organic single-crystalline semiconductors toward the integrated optoelectronic modules.

11.
Ecotoxicol Environ Saf ; 208: 111675, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396007

RESUMEN

Metal bioavailability controls its behaviors in soil-plant system, especially involved in biochar amendment. This study compared a rhizospheric pore-water extraction against a BCR sequential extraction method to understand cadmium (Cd) bioavailability in two typical Chinese soils. Soils were spiked with five levels of Cd (CdCl2) and remediated with 3% corn-straw derived biochar. After 60 days of lettuce growth, Cd accumulation and enzyme activities in tissues were analyzed. Results showed that biochar increased soil properties (pH, CEC and SOM) compared to un-amended soils, but decreased contents of bioavailable Cd in soil pore-water (Cdpore-water) and BCR extracted Cd (CdFi+Fii). Contents of Cdpore-water were lower in yellow-brown soils than that in red soils. Pearson analysis showed that bioavailable Cd is negatively correlated with soil pH and CEC (p < 0.05). Cd accumulation in lettuce roots and leaves both were decreased by biochar addition, and the established linear equations proved that soil Cdpore-water is the best predictor for Cd accumulation in lettuce roots (r2 = 0.964) and in leaves (r2 = 0.953), followed by CdFi+Fii. Transfer factor (TF) values of Cd from roots to leaves were lower than 1, and slightly better correlated with soil Cdpore-water (r = -0.674, p < 0.01) than CdFi+Fii (r = -0.615, p < 0.01). Aggregated boosted tree (ABT) analyses indicated that soil properties together with Cdpore-water contribute more than 50% to root enzyme activities. Collectively, soil Cdpore-water is a promising predictor of Cd bioavailability, accumulation and toxicity in soil-plant system with biochar addition.


Asunto(s)
Bioacumulación/efectos de los fármacos , Cadmio/toxicidad , Carbón Orgánico/química , Lactuca/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Disponibilidad Biológica , Transporte Biológico , Cadmio/metabolismo , Lactuca/metabolismo , Modelos Teóricos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Tallos de la Planta/química , Rizosfera , Suelo/química , Contaminantes del Suelo/metabolismo , Agua/química , Zea mays/química
12.
Med Sci Monit ; 24: 903-911, 2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29438359

RESUMEN

BACKGROUND Osteoporosis is associated with 17ß-estradiol deficiency. The G protein-coupled receptor 30 (GPR30) is known to be an estrogen-responsive receptor, but its role in the degradation of mitochondria in osteoblasts by autophagy, or mitophagy, remains unclear. The aim of this in vitro study was to evaluate the effects of 17ß-estradiol, GPR30, and its signaling pathway, on mitophagy in the murine MC3T3-E1 osteoblast cell line. MATERIAL AND METHODS In the murine MC3T3-E1 osteoblast cell line, cells were treated with 17ß-estradiol, or G15, a selective GPR30 antagonist, or U0126, a mitogen-activated protein (MAP) kinase (ERK1/2) inhibitor, or with vehicle as control. The expression of GPR30 was determined by Western blot, reverse transcription-polymerase chain reaction (RT-PCR), and confocal immunofluorescence imaging. Cell morphology and mitochondrial autophagosomes were identified using transmission electron microscopy (TEM). Phosphorylation of the mitophagy markers, heat shock protein 60 (Hsp60), translocase of outer membrane (Tom)20, and microtubule-associated protein 1A/1B-light chain 3 (LC3) were determined by Western blot, and cell proliferation was determined using the bromodeoxyuridine (BrdU) assay. RESULTS The optimum concentration of 17ß-estradiol that resulted in GPR30 expression in MC3T3-E1 cells was 10^-7 M, which led to the accumulation of mitochondrial autophagosomes and increased protein phosphorylation levels of Hsp60, Tom20, and LC3. In cells pretreated with G15 or U0126, 17b-estradiol treatment did not increase mitophagy in MC3T3-E1 cells. CONCLUSIONS In murine osteoblasts cultured in vitro, treatment with 17ß-estradiol resulted in the expression of GPR30 and enhanced mitophagy through the GPR30 and ERK1/2 signaling pathway.


Asunto(s)
Estradiol/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Mitofagia/efectos de los fármacos , Osteoblastos/metabolismo , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animales , Línea Celular , Citoprotección/efectos de los fármacos , Ratones , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/ultraestructura
13.
J Mater Sci Mater Med ; 26(4): 158, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25783501

RESUMEN

Magnesium (Mg) alloys have been demonstrated to be viable orthopedic implants because of mechanical and biocompatible properties similar to natural bone. In order to improve its osteogenic properties, a porous ß-tricalcium phosphate (ß-TCP) was coated on the Mg-3AI-1Zn alloy by alkali-heat treatment technique. The human bone-derived cells (SaOS-2) were cultured on (ß-TCP)-Mg-3AI-1Zn in vitro, and the osteoblast response, the morphology and the elements on this alloy surface were investigated. Also, the regulation of key intracellular signalling proteins was investigated in the SaOS-2 cells cultured on alloy surface. The results from scanning electron microscope and immunofluorescence staining demonstrated that (ß-TCP)-Mg-3AI-1Zn induced significant osteogenesis. SaOS-2 cell proliferation was improved by ß-TCP coating. Moreover, the (ß-TCP)-Mg-3AI-1Zn surface induced activation of key intracellular signalling proteins in SaOS-2 cells. We observed an enhanced activation of Src homology and collagen (Shc), a common point of integration between bone morphogenetic protein 2, and the Ras/mitogen-activated protein kinase (MAPK) pathway. ERK1/2 MAP kinase activation was also upregulated, suggesting a role in mediating osteoblastic cell interactions with biomaterials. The signalling pathway involving c-fos (member of the activated protein-1) was also shown to be upregulated in osteoblasts cultured on the (ß-TCP)-Mg-3AI-1Zn. These results suggest that ß-TCP coating may contribute to successful osteoblast function on Mg alloy surface. (ß-TCP)-Mg-3AI-1Zn may upregulate cell proliferation via Shc and ERK1/2 MAPK signaling in SaOS-2 osteoblasts grown on Mg alloy surface.


Asunto(s)
Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Sistema de Señalización de MAP Quinasas/fisiología , Magnesio/química , Osteoblastos/fisiología , Proteínas Adaptadoras de la Señalización Shc/metabolismo , Adsorción , Aleaciones/química , Línea Celular , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ensayo de Materiales , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología
14.
Knee Surg Sports Traumatol Arthrosc ; 23(11): 3354-61, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24928371

RESUMEN

PURPOSE: The effectiveness of cryotherapy on joint arthroplasty recovery remains controversial. This systematic review was conducted to assess the effectiveness of cryotherapy in patients after joint arthroplasty. METHODS: Comprehensive literature searches of several databases including Cochrane Library (2013), MEDLINE (1950-2013), and Embase (1980-2013) were performed. We sought randomised controlled trials that compared the experimental group received any form of cryotherapy with any control group after joint arthroplasty. The main outcomes were postoperative blood loss, adverse events, and pain. Analyses were performed with Revman 5.0. Results were shown as mean differences (MD) and standard deviations or as risk difference and 95 % confidence intervals (CIs). RESULTS: Ten trials comprised 660 total knee arthroplastys and three trials comprised 122 total hip arthroplastys (THAs) met the inclusion criteria. Blood loss was significantly decreased by cryotherapy (MD = -109.68; 95 % CI -210.92 to -8.44; P = 0.03). Cryotherapy did not increase the risk of adverse effect (n.s.). Cryotherapy decreased pain at the second day of postoperative (MD = -1.32; 95 % CI -2.37 to -0.27; P = 0.0003), but did not decreased pain at the first and third day of postoperative (n.s.). CONCLUSIONS: Cryotherapy appears effective in these selected patients after joint arthroplasty. The benefits of cryotherapy on blood loss after joint arthroplasty were obvious. However, the subgroup analysis indicated that cryotherapy did not decreased blood loss after THA. Cryotherapy did not increase the risk of adverse effect. Cryotherapy decreased pain at the second day of postoperative, but did not decreased pain at the first and third day of postoperative. LEVEL OF EVIDENCE: II.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/rehabilitación , Crioterapia , Articulación de la Rodilla/cirugía , Pérdida de Sangre Quirúrgica/prevención & control , Humanos , Dolor Postoperatorio/prevención & control , Cuidados Posoperatorios , Ensayos Clínicos Controlados Aleatorios como Asunto
15.
Sci Total Environ ; 918: 170695, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38331274

RESUMEN

The "background" is an essential index for identifying anthropogenic inputs and potential ecological risks of soil heavy metals. However, the lithology of bedrock can cause significant spatial variation in the natural background of soil elements, posing considerable difficulties in estimating background values. In this study, an attempt was made to calculate the natural background through regression analysis of soil chemical composition, and reasonably evaluate the impact of lithology. A total of 1771 surface soil samples were collected from the Songhua River Basin, China, for chemical composition analysis, and the partial least square regression (PLSR) method was employed to establish the relationship between heavy metals (As, Hg, Cr, Cd, Pb, Cu, Zn, and Ni) and soil chemical composition/environmental parameters (SiO2, Al2O3, TFe2O3, MgO, CaO, K2O, Na2O, La, Y, Zr, V, Sc, Sr, Li and pH). The result shows that As, Cr, Pb, Cu, Zn, and Ni have significant linear relationships with soil chemical composition. Each of these six heavy metals obtained 1771 regression background values; some were higher than the uniform background value obtained from the boxplot, while others were lower. The regression background values recognized not only subtle anthropogenic inputs and potential ecological risks in low-background regions but also spurious contamination in high-background areas. All these indicate that the PLSR method can effectively improve the determination accuracy of the natural background of soil heavy metals. More attention should be paid to the serious anthropogenic inputs appearing in some places of the study area.

16.
Adv Mater ; 36(23): e2314061, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38350441

RESUMEN

Colloidal quantum dots (CQDs) are considered a promising material for the next generation of integrated display devices due to their designable optical bandgap and low energy consumption. Owing to their dispersibility in solvents, CQD micro/nanostructures are generally fabricated by solution-processing methods. However, the random mass transfer in liquid restricts the programmable construction in macroscopy and ordered assembly in microscopy for the integration of CQD optical structures. Herein, a multi-interfacial confined assembly strategy is developed to fabricate CQDs programmable microstructure arrays with a quasisuperlattice configuration through controlling the dynamics of three-phase contact lines (TPCLs). The motion of TPCLs dominates the division of liquid film for precise positioning of CQD microstructures, while pinned TPCLs control the solvent evaporation and concentration gradient to directionally drive the mass transfer and packing of CQDs. Owing to their long-range order and adjustable structural dimensions, CQD microring arrays function as high-quality-factor (high-Q) lasing resonant cavities with low thresholds and tunable lasing emission modes. Through the further surface treatment and liquid dynamics control, the on-chip integration of red (R), green (G), and blue (B) multicomponent CQD microlaser arrays are demonstrated. The technique establishes a new route to fabricate large-area, ultrahigh-definition, and full-color CQD laser displays.

17.
Nat Commun ; 15(1): 2098, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459034

RESUMEN

Yutu-2 rover conducted an exciting expedition on the 41st lunar day to investigate a fin-shaped rock at Longji site (45.44°S, 177.56°E) by extending its locomotion margin on perilous peaks. The varied locomotion encountered, especially multi-form wheel slippage, during the journey to the target rock, established unique conditions for a fin-grained lunar regolith analysis regarding bearing, shear and lateral properties based on terramechanics. Here, we show a tri-aspect characterization of lunar regolith and infer the rock's origin using a digital twin. We estimate internal friction angle within 21.5°-42.0° and associated cohesion of 520-3154 Pa in the Chang'E-4 operational site. These findings suggest shear characteristics similar to Apollo 12 mission samples but notably higher cohesion compared to regolith investigated on most nearside lunar missions. We estimate external friction angle in lateral properties to be within 8.3°-16.5°, which fills the gaps of the lateral property estimation of the lunar farside regolith and serves as a foundational parameter for subsequent engineering verifications. Our in-situ spectral investigations of the target rock unveil its composition of iron/magnesium-rich low-calcium pyroxene, linking it to the Zhinyu crater (45.34°S, 176.15°E) ejecta. Our results indicate that the combination of in-situ measurements with robotics technology in planetary exploration reveal the possibility of additional source regions contributing to the local materials at the Chang'E-4 site, implying a more complicated geological history in the vicinity.

18.
Environ Pollut ; 330: 121803, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37187277

RESUMEN

Gold mining is the most important anthropogenic source of heavy metal emissions into the environment. Researchers have been aware of the environmental impacts of gold mining activities and have conducted studies in recent years, but they have only selected one gold mining site and collected soil samples in its vicinity for analysis, which does not reflect the combined impact of all gold mining activities on the concentration of potentially toxic trace elements (PTES) in nearby soils at a global scale. In this study, 77 research papers from 24 countries were collected from 2001 to 2022, and a new dataset was developed to provide a comprehensive study of the distribution characteristics, contamination characteristics, and risk assessment of 10 PTEs (As, Cd, Cr, Co, Cu, Hg, Mn, Ni, Pb, and Zn) in soils near the deposits. The results show that the average levels of all 10 elements are higher than the global background values and are at different levels of contamination, with As, Cd, and Hg at strong contamination levels and serious ecological risks. As and Hg contribute to a greater non-carcinogenic risk to both children and adults in the vicinity of the gold mine, and the carcinogenic risks of As, Cd, and Cu are beyond the acceptable range. Gold mining on a global scale has already caused serious impacts on nearby soils and should be given adequate attention. Timely heavy metal treatment and landscape restoration of extracted gold mines and environmentally friendly approaches such as bio-mining of unexplored gold mines where adequate protection is available are of great significance.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Oligoelementos , Adulto , Niño , Humanos , Oro/análisis , Suelo , Cadmio/análisis , Contaminantes del Suelo/análisis , Monitoreo del Ambiente/métodos , Metales Pesados/análisis , Mercurio/análisis , Oligoelementos/análisis , Medición de Riesgo , China
19.
Toxics ; 11(12)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38133362

RESUMEN

Lead contamination in soil has emerged as a significant environmental concern. Recently, pulse electrochemical treatment (PECT) has garnered substantial attention as an effective method for mitigating lead ions in low-permeability soils. However, the impact of varying pulse time gradients, ranging from seconds to hours, under the same pulse duty cycle on lead removal efficiency (LRE) and energy consumption in PECT has not been thoroughly investigated. In this study, a novel, modified PECT method is proposed, which couples PECT with a permeable reaction barrier (PRB) and adds acetic acid to the catholyte. A comprehensive analysis of LRE and energy consumption is conducted by transforming pulse time. The results show that the LREs achieved in these experiments were as follows: PCb-3 s (89.5%), PCb-1 m (91%), PCb-30 m (92.9%), and PCb-6 h (91.9%). Importantly, these experiments resulted in significant reductions in energy consumption, with decreases of 68.5%, 64.9%, 51.8%, and 47.4% compared to constant voltage treatments, respectively. It was observed that LRE improved with an increase in both pulse duration and voltage gradient, albeit with a corresponding rise in energy consumption. The results also revealed that corn straw biochar as a PRB could enhance LRE by 6.1% while adsorbing migrating lead ions. Taken together, the present data highlights the potential of modified PECT technology for remediation of lead-contaminated soil, which provides an optimal approach to achieve high LRE while minimizing energy consumption.

20.
Materials (Basel) ; 16(13)2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37445110

RESUMEN

Currently, as shown by large-scale research on two-dimensional materials in the field of nanoelectronics and catalysis, the construction of large-area two-dimensional materials is crucial for the development of devices and their application in photovoltaics, sensing, optoelectronics, and energy generation/storage. Here, using atmospheric-pressure chemical vapor deposition, we developed a method to regulate growth conditions according to the growth mechanism for WSe2 and MoSe2 materials. By accurately controlling the hydrogen flux within the range of 1 sccm and the distance between the precursor and the substrate, we obtained large-size films of single atomic layers with thicknesses of only about 1 nm. When growing the samples, we could not only obtain a 100 percent proportion of samples with the same shape, but the samples could also be glued into pieces of 700 µm and above in size, changing the shape and making it possible to reach the millimeter/submillimeter level visible to the naked eye. Our method is an effective method for the growth of large-area films with universal applicability.

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