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1.
Small ; 20(23): e2307292, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38169091

RESUMO

Layered Li-rich oxide cathode materials are capable of offering high energy density due to their cumulative cationic and anionic redox mechanism during (de)lithiation process. However, the structural instability of the layered Li-rich oxide cathode materials, especially in the deeply delitiated state, results in severe capacity and voltage degradation. Considering the minimal isotropic structural evolution of disordered rock salt oxide cathode during cycling, cation-disordered nano-domains have been controllably introduced into layered Li-rich oxides by co-doping of d0-TM and alkali ions. Combining electrochemical and synchrotron-based advanced characterizations, the incorporation of the phase-compatible cation-disordered domains can not only hinder the oxygen framework collapse along the c axis of layered Li-rich cathode under high operation voltage but also promote the Mn and anionic activities as well as Li+ (de)intercalation kinetics, leading to remarkable improvement in rate capability and mitigation of capacity and voltage decay. With this unique layered/rocksalt intergrown structure, the intergrown cathode yields an ultrahigh capacity of 288.4 mAh g-1 at 0.1 C, and outstanding capacity retention of ≈90.0% with obviously suppressed voltage decay after 100 cycles at 0.5, 1, and 2 C rate. This work provides a new direction toward advanced cathode materials for next-generation Li-ion batteries.

2.
Opt Lett ; 49(10): 2597-2600, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748114

RESUMO

We report an experimental investigation into the tight-focusing characteristics of linearly polarized inverse circular Airy beams (ICABs). Our study reveals that tightly focused ICABs exhibit Bessel-like, needle-like, or dual foci profiles depending on whether the main ring's radius is smaller than, equal to, or larger than the critical radius. The emergence of the dual foci structure is attributed to the constrained entrance aperture of the microscope objective (MO). In contrast to traditional Gaussian beams (GBs), ICABs demonstrate remarkable advantages in terms of focal spot size. Notably, we observe a focal spot with a size of 245 nm, representing a 26.4% reduction compared to the diffraction limit. These unique properties open up promising avenues for potential applications in optical multi-plane particle trapping, conveying, and super-resolution optical imaging.

3.
Chemphyschem ; 25(15): e202400330, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38676545

RESUMO

Copper is widely used in everyday life and industrial production because of its good electrical and thermal conductivity. To overcome copper oxidation and maintain its good physical properties, small organic molecules adsorbed on the surface of copper make a passivated layer to further avoid copper corrosion. In this work, we have investigated thioglycolic acid (TGA, another name is mercaptoacetic acid) adsorbed on copper surfaces by using density functional theory (DFT) calculations and a periodical slab model. We first get five stable adsorption structures, and the binding interaction between TGA and Cu(111) surfaces by using density of states (DOS), indicating that the most stable configuration adopts a triple-end binding model. Then, we analyze the vibrational Raman spectra of TGA adsorbed on the Cu(111) surface and make vibrational assignments according to the vibrational vectors. Finally, we explore the temperature effect of the thermodynamically Gibbs free energy of TGA on the Cu(111) surface and the antioxidant ability of the small organic molecular layer of copper oxidation on the copper surface. Our calculated results further provide evidences to interpret the stability of adsorption structures and antioxidant properties of copper.

4.
Angew Chem Int Ed Engl ; 63(13): e202318721, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38294414

RESUMO

Two-dimensional (2D) layered materials demonstrate prominent advantage in regulating lithium plating/stripping behavior by confining lithium diffusion/plating within interlayer gaps. However, achieving effective interlayer confined lithium diffusion/plating without compromising the stability of bulk-structural and the solid electrolyte interphase (SEI) remains a considerable challenge. This paper presents an electrochemical scissor and lithium zipper-driven protocol for realizing interlayer confined lithium plating with pretty-low strain and volume change. In this protocol, lithium serves as a "zipper" to reunite the adjacent MXene back to MAX-like phase to markedly enhance the structural stability, and a lithium halide-rich SEI is formed by electrochemically removing the terminals of halogenated MXenes to maintain the stability and rapid lithium ions diffusion of SEI. When the Ti3 C2 I2 serves as the host for lithium plating, the average coulomb efficiency exceeds 97.0 % after 320 lithium plating/stripping cycles in conventional ester electrolyte. Furthermore, a full cell comprising of LiNi0.8 Mn0.1 Co0.1 O2 and Ti3 C2 I2 @Li exhibits a capacity retention rate of 73.4 % after 200 cycles even under high cathode mass-loading (20 mg cm-2 ) and a low negative/positive capacity ratio of 1.4. Our findings advance the understanding of interlayer confined lithium plating in 2D layered materials and provide a new direction in regulating lithium and other metal plating/stripping behaviors.

5.
Small ; : e2309064, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059860

RESUMO

With theoretically endowing with high energy densities and environmentally friendly carbon neutralization ability, flexible fiber-shaped Li-CO2 battery emerges as a multipurpose platform for next-generation wearable electronics. Nevertheless, the ineluctable issues faced by cathode catalysts and Li anodes have brought enormous obstacles to the development of flexible fiber-shaped Li-CO2 batteries. Herein, a flexible fiber-shaped Li-CO2 battery based on Mo3 N2 cathode coating with atomic layer deposited TiN and Li3 N protected Li anode is constructed. Owing to the regulation surface electrons of Mo3 N2 by TiN, heterostructured cathode has more delocalized electrons which enable cathodes to stabilize 2-electron intermediate products Li2 C2 O4 by electron bridge bonds and avoid disproportionation into Li2 CO3 . Li3 N layers not only accelerate Li+ transportation but also avoid contact between Li and CO2 to form Li2 CO3 . Thus, the constructed Li-CO2 battery demonstrates a low charge potential of 3.22 V, low overpotential of 0.56 V, outstanding rate capabilities up to 1 A g-1 , and excellent long-term cycling (≈2000 h) with an energy efficiency of ≈80%. The fabricated flexible fiber-shaped Li-CO2 battery shows an ultrahigh energy density of 14 772.5 Wh kg-1 based on cathodes (340.8 Wh kg-1 based on device mass), and outstanding deformations adaptability, giving it great potential for wearable electronics.

6.
Small ; 19(42): e2301301, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37340577

RESUMO

High-capacity silicon has been regarded as one of the most promising anodes for high-energy lithium-ion batteries. However, it suffers from severe volume expansion, particle pulverization, and repeated solid electrolyte interphase (SEI) growth, which leads to rapid electrochemical failure, while the particle size also plays key role here and its effects remain elusive. In this paper, through multiple-physical, chemical, and synchrotron-based characterizations, the evolutions of the composition, structure, morphology, and surface chemistry of silicon anodes with the particle size ranging from 50 to 5 µm upon cycling are benchmarked, which greatly link to their electrochemical failure discrepancies. It is found that the nano- and micro-silicon anodes undergo similar crystal to amorphous phase transition, but quite different composition transition upon de-/lithiation; at the same time, the nano- and 1 µm-silicon samples present obviously different mechanochemical behaviors from the 5 µm-silicon sample, such as electrode crack, particle pulverization/crack as well as volume expansion; in addition, the micro-silicon samples possess much thinner SEI layer than the nano-silicon samples upon cycling, and also differences in SEI compositions. It is hoped this comprehensive study and understanding should offer critical insights into the exclusive and customized modification strategies to diverse silicon anodes ranging from nano to microscale.

7.
J Org Chem ; 88(8): 5147-5152, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36520533

RESUMO

2-Arylindoles are privileged structures widely present in biologically active molecules. New sustainable synthetic routes toward their synthesis are, therefore, in high demand. Herein, a mixed base-promoted benzylic C-H deprotonation of commercially available ortho-anisoles, addition of the resulting anion to benzonitriles, and SNAr to displace the methoxy group provide indoles. A diverse array of 2-arylindoles is prepared with good yields (>30 examples, yields up to 99%) without added transition metal catalysts.

8.
Mol Divers ; 27(2): 571-588, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35666432

RESUMO

To search a novel lead structure for antiphytopathogenic fungus agent, a series of novel psoralen derivatives possessing sulfonohydrazide or acylthiourea structure were designed and synthesized, and their fungicidal activity against seven phytopathogens was evaluated. Their structures were confirmed by melting points, 1H NMR, 13C NMR and HRMS, and the typical crystal structure was determined by X-ray diffraction for validation. Preliminary fungicidal activity showed that some of the title compounds exhibited certain-to-high fungicidal activity. Compound I-13 exhibited good fungicidal activity against Botrytis cinerea, Cercospora arachidicola and Physalospora piricola with EC50 values of 12.49, 13.22 and 12.12 µg/mL, respectively. Compounds II-9 and II-15 showed over 90% inhibition against B. cinerea at 50 µg/mL in vitro. In particular, II-9 exhibited significant higher fungicidal activity with a lower EC50 value of 9.09 µg/mL than the positive control YZK-C22 (13.41 µg/mL). Our studies found that sulfonohydrazide or acylthiourea-containing psoralen derivatives were promising fungicide leads deserve for further study.


Assuntos
Fungicidas Industriais , Furocumarinas , Relação Estrutura-Atividade , Antifúngicos/farmacologia
9.
Ecotoxicol Environ Saf ; 253: 114688, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842277

RESUMO

The soil contamination caused by the discharge of cadmium (Cd) from coal mining activities has aroused continuous attention due to the detrimental effects on the human health. This study aimed to investigate the characteristics on distribution of Cd in soils and its accumulation in wheat grains under wheat-cultivation system, and further assess the human health risks to adults and children. 58 soils and wheat samples in pairs from Linhuan coal mining area, Anhui Province were collected and analyzed. Results showed that the concentrations of Cd in 17.24% of soil samples exceeded the limit value established by the Ministry of Ecology and Environment. The ordinary kriging interpolation displayed that the spatial variability of Cd concentrations in soils was mainly influenced by coal mining activities. The transfer capacity of Cd from soils to wheat roots was greater than that from the wheat roots to grains. Multiple linear regression model clarified that soil pH and exchangeable Cd fraction in soils were the critical factors affecting the Cd accumulation in wheat grains. The carcinogenic risk of Cd levels in our studied wheat grains was a concern but still within the acceptable range, while their non-carcinogenic hazard was negligible for adults and children. The calculation results were in accord with the uncertainty analysis conclusion based on Monte Carlo simulation. The study was expected to promote the source management and control strategy of reducing tailing discharge, and providing scientific references for current soil remediation and land degradation prevention.


Assuntos
Minas de Carvão , Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Cádmio/metabolismo , Solo , Triticum/metabolismo , Monitoramento Ambiental , Poluentes do Solo/análise , China , Medição de Risco , Metais Pesados/análise
10.
Environ Geochem Health ; 45(5): 2241-2262, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35918576

RESUMO

Chromium (Cr), one of the prime hazardous trace elements in coals, may engender adverse effects on eco-environment and threaten human health during utilization of coal. Based on the samples obtained in our laboratory and published literature, the abundance and modes of occurrence of Cr in Chinese coals, and the environmental impacts associated with coal-fired power plants (CFPPs) were elucidated in this study. With a total of 1397 sets of data, the mean concentration of Cr in Chinese coals was calculated as 21.33 µg/g by the "reserve-concentration" weighted calculation method. Spatially, the average Cr contents increased gradually from North China to South China. Temporally, coals from T3, E-N and P2 were relatively enriched in Cr compared to the other geological time. The Cr concentration in coal varied with different coal ranks. The geological factors accounted for Cr enrichment in coals could be divided into the primary, secondary and epigenetic processes. Higher percentages of organically Cr occurred in low-rank coals, while inorganically associated Cr was mainly found in clay minerals. After coal combustion, most of Cr was enriched in solid wastes (e.g., fly ash and bottom ash). The leaching of Cr from solid wastes in the rainy season (especially acid rain) needs to be a concern for CFPPs. It was estimated that the atmospheric emission of Cr from CFPPs increased annually from 2015 to 2019 and reached approximately 159 tons in 2019.


Assuntos
Cromo , Carvão Mineral , China , Cromo/toxicidade , Carvão Mineral/análise , Cinza de Carvão/análise , Centrais Elétricas , Resíduos Sólidos
11.
Environ Geochem Health ; 45(8): 5813-5827, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37148428

RESUMO

In this research, enrichment factor (EF) and pollution load index were utilized to explore the contamination characteristics of toxic elements (TEs) in park dust. The results exhibited that park dust in the study area was mainly moderately polluted, and the EF values of dust Cd, Zn, Pb, Cu and Sb were all > 1. The concentrations of Cr, Cu, Zn and Pb increased with the decrease of dust particle size. The investigation results of chemical speciation and bioavailability of TEs showed that Zn had the highest bioavailability. Three sources of TEs were determined by positive matrix factorization model, Pearson correlation analysis and geostatistical analysis, comprising factor 1 mixed sources of industrial and transportation activities (46.62%), factor 2 natural source (25.56%) and factor 3 mixed source of agricultural activities and the aging of park infrastructures (27.82%). Potential ecological risk (PER) and human health risk (HHR) models based on source apportionment were exploited to estimate PER and HHR of TEs from different sources. The mean PER value of TEs in the park dust was 114, indicating that ecological risk in the study area was relatively high. Factor 1 contributed the most to PER, and the pollution of Cd was the most serious. There were no significant carcinogenic and non-carcinogenic risks for children and adults in the study area. And factor 3 was the biggest source of non-carcinogenic risk, and As, Cr and Pb were the chief contributor to non-carcinogenic risk. The primary source of carcinogenic risk was factor 2, and Cr was the cardinal cancer risk element.


Assuntos
Monitoramento Ambiental , Metais Pesados , Adulto , Criança , Humanos , Monitoramento Ambiental/métodos , Poeira/análise , Cádmio/toxicidade , Cádmio/análise , Chumbo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Medição de Risco/métodos , Carcinógenos/análise , China , Cidades
12.
Pak J Med Sci ; 39(2): 444-449, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950412

RESUMO

Objective: To evaluate the clinical efficacy of a chemotherapy regimen combined with levofloxacin in patients with pulmonary tuberculosis complicated with Type-2 diabetes. Methods: Total 80 patients with pulmonary tuberculosis complicated with Type-2 diabetes admitted to Baoding People's Hospital from January, 2019 to January, 2022 were randomly divided into two groups: the experimental group and the control group, with 40 cases in each group. Patients in the control group were given the conventional 2HRZE/10HRE regimen, while those in the experimental group were given the chemotherapy regimen 2HRZEL/6HRE combined with levofloxacin. Sixty four slice spiral CT was used for chest plain scan before and after treatment, respectively, to evaluate the absorption of lesions based on the range of lung lesions; Venous blood was drawn to detect the changes of oxidative stress indicators, the incidence of adverse drug reactions and the negative conversion rate of sputum tuberculosis bacteria in the two groups. Results: After treatment, the efficacy of the experimental group was 90%, which was significantly higher than that of the control group (67.5%), with a statistically significant difference (p=0.01). After treatment, CD3+, CD4+, CD4+/CD8+ and other indicators in the experimental group were significantly higher than those in the control group, with a statistically significant difference (CD3+, p=0.01; CD4+, p=0.01; CD4+/CD8+, p=0.00), while CD8+ did not change significantly (p=0.92); The incidence of adverse reactions was 52.5% in the experimental group and 47.5% in the control group, with no statistically significant difference (p=0.66); The negative conversion rate of patients in the experimental group was significantly higher than that in the control group at one month, three months and six months after treatment, with a statistically significant difference (p<0.05). Conclusion: Chemotherapy combined with levofloxacin is a safe and effective regimen for patients' pulmonary tuberculosis complicated with Type-2 diabetes, boasting a variety of benefits such as improved clinical efficacy, ameliorated cellular immune status, a high negative conversion rate of sputum tuberculosis bacteria, and no significant increase in adverse reactions.

13.
Opt Lett ; 47(8): 2109-2112, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427349

RESUMO

We report experimental realization and manipulation of optical tornado waves (ToWs). By controlling the self-focusing length, total angular momentum, and foci deviation of ToWs, the propagation properties of optical ToWs, especially their angular velocity, can be manipulated. Controlling the accumulated rotation angle of the main intensity lobes of ToWs from 0° through 1100° is experimentally demonstrated, and their angular velocity is predicted to be the highest around the foci overlap situation. Our experimental results are in good agreement with numerical results.

14.
Phys Chem Chem Phys ; 24(5): 2879-2886, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35060570

RESUMO

Although lithium-sulfur (Li-S) batteries with a high theoretical energy density and low cost have attracted extensive research attention, their commercialization is still unsuccessful due to the poor cycle life caused by the dissolution of polysulfides. It is the key challenge to overcome polysulfide shuttling for achieving long-term cycling stability in Li-S batteries. Here we report a novel strategy for the synthesis of N, S-doped graphene with high nitrogen and sulfur contents via in situ self-assembly of graphene oxide and thiourea-formaldehyde resin and calcination. The N, S-doped graphene serves as a conductive agent and a chemosorbent for suppressing polysulfide shuttling and preventing the Li-metal from corrosion, leading to a high reversible capacity and superior cycling stability. The Li-S batteries with the N, S-doped graphene can achieve an excellent cycling life (622 mA h g-1 after 500 cycles at 1C) and a slow capacity decay rate (0.049% per cycle over 500 cycles at 1C). The proposed strategy has the potential to enhance the high electrochemical properties of Li-S batteries.

15.
Environ Monit Assess ; 194(3): 206, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190909

RESUMO

Non-ferrous metal smelting activities have always been considered as one of the foremost anthropogenic sources of potentially toxic elements (PTEs). The enrichment factor (EF) and pollution load index (PLI) were used to evaluate the pollution level of soil PTEs; positive matrix factorization (PMF), correlation analysis, and geostatistics were utilized to quantify the sources of soil PTEs; and potential ecological risk (PER) and human health risk (HHR) of different sources from farmland, construction land, and natural land were quantifiably determined via combined PTE sources with PER and HHR assessment models. Taking the smelting area of Daye City as an example, the evaluation results of EF and PLI showed that the soil PTE pollution in the study area was serious, especially Cd and Cu. And four sources were quantitatively allocated as agricultural practices (12.14%), traffic emissions (23.07%), natural sources (33.46%), and industrial activities (31.33%). For PER, industrial activities were the largest contributor to PER, accounting for 55.66%, 56.30%, and 55.36% of farmland, construction land, and natural land, respectively, and Cd was the most dangerous element. In terms of HHR, industrial activities were also the cardinal contributors under the three land use types. Children were exposed to serious non-carcinogenic risks under three land use patterns and slight carcinogenic risk in construction land (1.06E - 04). Significantly, the carcinogenic risk of children in farmland (9.06 × 10-5) was very close to the threshold (1 × 10-4), which requires attention. Both non-carcinogenic and carcinogenic risk for adults were all at acceptable levels. The health risks (carcinogenic and non-carcinogenic risks) of children from four different sources were distinctly higher than those of adults. Consequently, strict management and control of industrial activities should be given priority, and the management of agricultural practices should not be ignored.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , China , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
16.
Pak J Med Sci ; 38(1): 179-184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035422

RESUMO

OBJECTIVE: To observe the clinical efficacy of thymosin alpha 1 (Tα1) combined with multi-modality chemotherapy in patients with pulmonary tuberculosis (PTB) complicated with diabetes and discuss the effects of such combination therapy on lymphocyte subsets and sputum levels of cytokines. METHODS: A total of 120 patients with PTB complicated with diabetes admitted to the Affiliated Hospital of North China University of Science and Technology from January 2017 to January 2018 were included in this study and randomly divided into an experimental group (Tα1 group, n=60) and a control group (n=60). Clinical efficacy and adverse drug reactions were observed and compared between the two groups. Blood samples were collected for lymphocyte (NK cell and T cell subsets) levels by flow cytometry, and sputum samples were collected for cytokine (IL-2, IFN-γ, IL-4 and TNF-α) levels by ELISA. RESULTS: Two groups showed no statistically significant difference in sputum culture-negative conversion rate, chest lesion absorption rate, and cavity closure rate (P>0.05) after 6 months of treatment. However, after 12 months, the sputum culture-negative conversion rate, chest lesion absorption rate, and cavity closure rate in the Tα1 group increased compared with the control group, and the differences were statistically significant (P<0.05). There was a significant increase in CD3+, CD4+, NK-cells lymphocytes after six months in the Tα1 group than in the control group, whereas the CD8+, Th17, Treg lymphocytes in the Tα1 group were substantially lower than in the control group, with the differences showing statistical significance (P<0.05, respectively). After six months of treatment, the sputum supernatant levels of interleukin-4 (IL-4) and tumor necrosis factor α (TNF-α) in the Tα1 group were lower than in the control group, whereas the sputum supernatant levels of interleukin-2 (IL-2) and interferon gamma (IFN-γ) in the Tα1 group were higher than in the control group, and the differences were statistically significant (P<0.05, respectively). There was no statistically significant difference in the incidence of adverse reactions between the two groups (P>0.05). CONCLUSION: Tα1 combined with multi-modality chemotherapy has a visible curative effect on PTB patients with diabetes as it can regulate immune function and reduce the levels of inflammatory cytokines. As a safe combination therapy, it seems promising for further use in clinical practice.

17.
Mol Divers ; 25(4): 2379-2388, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32734588

RESUMO

A series of novel pyrazole-4-carboxamides were rationally designed, synthesized, and their structures were characterized by 1H NMR, 13C NMR and HRMS. Preliminary bioassay showed that four compounds 8g, 8j, 8o and 8s exhibited more than 90% and even completed inhibition against Alternaria solani at 100 µg/mL; and 8d displayed 100% inhibition against Fusarium oxysporum at the same concentration. Moreover, 8j exhibited good in vitro fungicidal activity against A. solani with EC50 value of 3.06 µg/mL, and it also displayed completed in vivo protective antifungal activity against A. solani on tomato at 10 mg/L, as boscalid did. The molecular docking results indicated that 8j exhibited the high affinity with SDH protein by H-bond and π-π stacking interactions, which may explain the reasons for its good activities. These data support that compound 8j could be used as a fungicide candidate for further study. A practical method for the synthesis of pyrazole-4-carboxamides were provided and evaluation of their antifungal activities.


Assuntos
Fungicidas Industriais
18.
Ecotoxicol Environ Saf ; 208: 111489, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33080423

RESUMO

To make pollution evaluation of potentially hazardous elements in the soil more accurately, the regional geochemical baseline concentrations of eight potentially hazardous elements (Cr, Ni, Cu, Zn, As, Cd, Hg, and Pb) were established in Huilai County using cumulative frequency distribution curves. Then, the pollution load index and enrichment factor were applied to estimate the contamination levels, based on these geochemical baseline concentrations. The results suggested that topsoil was moderately polluted by potentially hazardous elements, while Cd pollution in the construction land and As pollution in the farmland was relatively severe. The possible sources of eight potentially hazardous elements were analyzed by correlation analysis, geostatistics and positive matrix factorization. Four sources have been determined and apportioned, namely industrial activities, natural sources, agricultural practices, and traffic emissions. Combining the health risk assessment with the source profiles, the health risks quantified from four sources were estimated under farmland, construction land, and woodland. The results showed that agricultural practices were the most main source of non-cancer and cancer risks under woodland and farmland for adults; industrial activities were the most main source of non-cancer and cancer risks under construction land for adults. Children's health risks, both carcinogenic risk and non-carcinogenic risk, were greater than adults, and the health risk trends of adults and children showed similarities. Therefore, agricultural practices under woodland and farmland should be controlled and managed as a priority, while industrial activities should be given priority to control and management under construction land.


Assuntos
Exposição Ambiental , Metais/análise , Poluentes do Solo/análise , Solo/química , China , Monitoramento Ambiental , Humanos , Medição de Risco
19.
Development ; 144(4): 580-589, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28087623

RESUMO

In the field of heart regeneration, the proliferative potential of cardiomyocytes in postnatal mice is under intense investigation. However, solely relying on immunostaining of proliferation markers, the long-term proliferation dynamics and potential of the cardiomyocytes cannot be readily addressed. Previously, we found that a p53 promoter-driving reporter predominantly marked the proliferating lineages in mice. Here, we established a p53-based genetic tracing system to investigate postnatal cardiomyocyte proliferation and heart regeneration. By selectively tracing proliferative cardiomyocytes, a differential pattern of clonal expansion in p53+ cardiac myocytes was revealed in neonatal, adolescent and adult stages. In addition, the percentage of p53+ lineage cardiomyocytes increased continuously in the first month. Furthermore, these cells rapidly responded to heart injury and greatly contributed to the replenished myocardium. Therefore, this study reveals complex proliferating dynamics in postnatal cardiomyocytes and heart repair, and provides a novel genetic tracing strategy for studying postnatal cardiac turnover and regeneration.


Assuntos
Coração/fisiologia , Miócitos Cardíacos/metabolismo , Regeneração/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem da Célula , Proliferação de Células , Vasos Coronários/fisiologia , Modelos Animais de Doenças , Genes Reporter , Genes p53 , Proteínas de Fluorescência Verde/metabolismo , Ventrículos do Coração/metabolismo , Processamento de Imagem Assistida por Computador , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio , Miocárdio/metabolismo
20.
Opt Express ; 28(24): 36516-36526, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379744

RESUMO

We investigate the self-healing property of focused circular Airy beams (FCAB), and this property is associated with the transverse Poynting vector (energy flow) for a better interpretation. We both experimentally and numerically show the effect of the obstruction's position, size and shape on the self-healing property of FCAB. It is found that FCAB will heal if the obstruction is placed at the area between the two foci of FCAB, and it has the least influence on the FCAB when the obstruction is placed near the lens' rear focal plane, whereas FCAB cannot heal if the obstruction is out of the area between two foci. Our experimental results are in good agreement with numerical results.

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