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1.
Environ Res ; 247: 118134, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38237755

RESUMO

Urbanization-related human activities, such as population aggregation, rapid industrial expansion, and intensified traffic, are key factors that impact local polycyclic aromatic hydrocarbon emissions and their associated health risks. Consequently, regions with varying degrees of urbanization within a megacity may exhibit diverse spatiotemporal patterns in the presence and distribution of soil polycyclic aromatic hydrocarbons, resulting in different levels of ecological risks for local inhabitants following the same period of development. In this study, we measured the concentrations of 16 polycyclic aromatic hydrocarbons in soil samples collected from industrial district and rural district in Tianjin (China) in 2018, and compared with polycyclic aromatic hydrocarbon data in 2001 from a previous study to characterize these regional variations in occurrence, source, and human risk of polycyclic aromatic hydrocarbons induced by urbanization with time and space. The results indicate the 20-year rapid urbanization and industrialization has differentially affected the composition, distribution and sources of polycyclic aromatic hydrocarbons in soils from different economic functional zones in Tianjin. Additionally, its impact on health risks in rural district appeared to be more significant than that in industrial district.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Poluentes do Solo/análise , Medição de Risco , Poluição Ambiental , China , Solo
2.
Mikrochim Acta ; 191(1): 70, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165510

RESUMO

A smartphone-assisted, paper-based ratio fluorescence probe is presented for the rapid, low-cost and on-site quantification of total flavonol glycosides in Ginkgo biloba extracts (GBE). The Al3+/Eu-MOF/paper-based probe utilizes lanthanide metal-organic framework (Ln-MOF) nanoparticles immobilized on Whatman filter paper along with Al3+ for detecting flavonols, which are the hydrolyzed products of flavonol glycosides. The color change of the paper-based fluorescence image from red to orange depends on the concentration of the target analyte in the sample solution. The smartphone equipped with a red, green, blue (RGB) color detector measured the fluorescence signal intensity on the paper substrate after adding flavonol. The analytical variables affecting the performance of the probe, including the addition sequence of the aluminum nitrate solution, its concentration, that of the Ln-MOF solution, the drying time of the paper probe, the reaction time and the sensitivity parameters of the mobile phone camera (ISO), were optimized. Under optimal conditions, the Al3+/Eu-MOF/paper-based probe has good linear response in the concentration range 7 ~ 80 µg mL- 1 and a lower detection limit of 2.07 µg mL- 1. The results obtained with the paper-based ratio fluorescence probe and smartphone combination were validated by comparing them with high-performance liquid chromatography (HPLC) measurements. This study provides a potential strategy for fabricating Al3+/Eu-MOF/paper-based probe used for total flavonol glycosides determination.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Smartphone , Diagnóstico por Imagem , Flavonóis , Glicosídeos , Extratos Vegetais
3.
Environ Geochem Health ; 46(6): 185, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695908

RESUMO

Microplastics (MPs), as emerging contaminants, usually experience aging processes in natural environments and further affect their interactions with coexisted contaminants, resulting in unpredictable ecological risks. Herein, the effect of MPs aging on their adsorption for coexisting antibiotics and their joint biotoxicity have been investigated. Results showed that the adsorption capacity of aged polystyrene (PS, 100 d and 50 d) for ciprofloxacin (CIP) was 1.10-4.09 times higher than virgin PS due to the larger BET surface area and increased oxygen-containing functional groups of aged PS. Following the increased adsorption capacity of aged PS, the joint toxicity of aged PS and CIP to Shewanella Oneidensis MR-1 (MR-1) was 1.03-1.34 times higher than virgin PS and CIP. Combined with the adsorption process, CIP posed higher toxicity to MR-1 compared to aged PS due to the rapid adsorption of aged PS for CIP in the first 12 h. After that, the adsorption process tended to be gentle and hence the joint toxicity to MR-1 was gradually dominated by aged PS. A similar transformation between the adsorption rate and the joint toxicity of PS and CIP was observed under different conditions. This study supplied a novel perception of the synergistic effects of PS aging and CIP on ecological health.


Assuntos
Ciprofloxacina , Poliestirenos , Shewanella , Ciprofloxacina/química , Ciprofloxacina/toxicidade , Poliestirenos/toxicidade , Poliestirenos/química , Adsorção , Shewanella/efeitos dos fármacos , Microplásticos/toxicidade , Microplásticos/química , Antibacterianos/química , Antibacterianos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química
4.
J Cell Mol Med ; 27(20): 3017-3025, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37603376

RESUMO

Dilated cardiomyopathy (DCM) is a disease with no specific treatment, poor prognosis and high mortality. During DCM development, there is apoptosis, mitochondrial dynamics imbalance and changes in cristae structure. Optic atrophy 1 (OPA1) appears at high frequency in these three aspects. DCM LMNA (LaminA/C) gene mutation can activate TP53, and the study of P53 shows that P53 affects OPA1 through Bak/Bax and OMA1 (a metalloprotease). OPA1 can be considered the missing link between DCMp53 and DCM apoptosis, mitochondrial dynamics imbalance and changes in cristae structure. OPA1 regulates apoptosis by regulating the release of cytochrome c from the mitochondrial matrix through CJs (crisp linkages, located in the inner mitochondrial membrane) and unbalances mitochondrial fusion and fission by affecting mitochondrial inner membrane (IM) fusion. OPA1 is also associated with the formation and maintenance of mitochondrial cristae. OPA1 is not the root cause of DCM, but it is an essential mediator in P53 mediating the occurrence and development of DCM, so OPA1 also becomes a molecular regulator of DCM. This review discusses the implication of OPA1 for DCM from three aspects: apoptosis, mitochondrial dynamics and ridge structure.

5.
Protein Expr Purif ; 211: 106338, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37460032

RESUMO

SIRT6 and SIRT7, as members of the Sirtuins family, are indispensable for the growth and development of Drosophila. They play crucial roles in maintaining genome stability, regulating metabolic senescence, and controlling tumorigenesis. To investigate their involvement in the Drosophila life cycle, we focused on describing the expression and purification of recombinant Drosophila SIRT6 and SIRT7 proteins. Subsequently, these proteins were utilized for generating polyclonal antibodies against Drosophila SIRT6 and SIRT7. The recombinant expression plasmid was introduced into E. coli cells to enable the production of SIRT6 and SIRT7 proteins. Following immunizations of New Zealand white rabbits and guinea pigs with the recombinant proteins as antigens, specific polyclonal antisera against both proteins were obtained. After purification, the specificity of SIRT6 and SIRT7 was confirmed using ELISA and western blot analyses, demonstrating strong specificity. These antibodies hold promise for the development of detection assays required for further research.


Assuntos
Sirtuínas , Animais , Cobaias , Coelhos , Anticorpos , Drosophila/genética , Drosophila/metabolismo , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Sirtuínas/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
6.
J Environ Manage ; 334: 117432, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36764192

RESUMO

Constructed wetlands (CWs) have been expected advantages in emerging pollutant removal, but with less known on their characteristic when treating wastewater containing graphene oxide (GO). In present study, we investigated characteristics of Iris pseudacorus, microorganisms, and pollutant removal in CWs with 60 cm and 37 cm water level (termed HCW and LCW). Plants in LCW had higher chlorophyll content and lower activities of antioxidant enzyme (superoxide dismutase, catalase, peroxidase) as well as malondialdehyde content. Substrate enzyme activities were affected by time and CW type. LCW increased only dehydrogenase activities, while HCW increased catalase, urease, neutral phosphatase, and arylsulfatase activities. Sequencing analysis revealed that microbial community showed higher richness and diversity in LCW, but this dissimilarity could be eased by time-effect. Proteobacteria (25.62-60.36%) and Actinobacteria (13.86-56.20%) were stable dominant phyla in CWs. Ratio of Proteobacteria/Acidobacteria indicated that trophic status of plant rhizosphere zone was lower in LCW. Nitrospirae were enriched to 0.16-0.68% and 0.75-1.42% in HCW and LCW. The enrichment of phyla Proteobacteria and Firmicutes in HCW was attributed to class Gammaproteobacteria and genus Enterococcus. GO transformation showed some reductions in CWs, which could be affected by water depth and substrate depth. Overall, HCW achieved nitrogen and phosphorus removal for 48.78-62.99% and 95.01%, which decreased by 8.41% and 7.31% in LCW. COD removal was less affected reaching 93%. This study could provide some new evidence for CWs to treat wastewater containing GO.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Catalase , Áreas Alagadas , Plantas , Bactérias , Nitrogênio/análise
7.
J Integr Plant Biol ; 65(5): 1170-1182, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36647626

RESUMO

Terpenes are the largest and most diverse class of plant specialized metabolites. Sesterterpenes (C25), which are derived from the plastid methylerythritol phosphate pathway, were recently characterized in plants. In Arabidopsis thaliana, four genes encoding geranylfarnesyl diphosphate synthase (GFPPS) (AtGFPPS1 to 4) are responsible for the production of GFPP, which is the common precursor for sesterterpene biosynthesis. However, the interplay between sesterterpenes and other known terpenes remain elusive. Here, we first provide genetic evidence to demonstrate that GFPPSs are responsible for sesterterpene production in Arabidopsis. Blockage of the sesterterpene pathway at the GFPPS step increased the production of geranylgeranyl diphosphate (GGPP)-derived terpenes. Interestingly, co-expression of sesterTPSs in GFPPS-OE (overexpression) plants rescued the phenotypic changes of GFPPS-OE plants by restoring the endogenous GGPP. We further demonstrated that, in addition to precursor (DMAPP/IPP) competition by GFPPS and GGPP synthase (GGPPS) in plastids, GFPPS directly decreased the activity of GGPPS through protein-protein interaction, ultimately leading to GGPP deficiency in planta. Our study provides a new regulatory mechanism of the plastidial terpenoid network in plant cells.


Assuntos
Arabidopsis , Dimetilaliltranstransferase , Terpenos/metabolismo , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Sesterterpenos/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plastídeos/metabolismo
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(9): 1359-1367, 2023.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38044647

RESUMO

PKM2, also known as M2-type pyruvate kinase, has attracted significant attention due to its crucial role in glycolysis and its abnormal expression in various tumors. With the discovery of PKM2's non-metabolic functions, the transition between its pyruvate kinase activity (in the tetrameric form in the cytoplasm) and protein kinase activity (in the dimeric form in the nucleus) has once again made PKM2 a target of interest in cancer research. Studies have shown that PKM2 is a protein susceptible to various post-translational modifications, and different post-translational modifications play important regulatory roles in processes such as PKM2 cellular localization, structure, and enzyme activity conversion. In this review, we focused on the recent progress of multiple post-translational modifications of PKM2 and their important roles in tumor initiation and development. For example, phosphorylation and acetylation promote nuclear translocation by altering PKM2 cell localization; glycosylation and ubiquitination can promote the formation of dimer structure by affecting the structural transformation of PKM2; succinylation and redox modification promoted the enhancement of PKM2 kinase activity by affecting the transformation of kinase activity. Both changes affect the structure and cell localization of PKM2 and they play a role in promoting or inhibiting tumor development via altering its kinase activity.


Assuntos
Neoplasias , Piruvato Quinase , Humanos , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Neoplasias/patologia , Fosforilação , Transformação Celular Neoplásica , Processamento de Proteína Pós-Traducional , Glicólise
9.
Diabetologia ; 65(9): 1461-1472, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35705796

RESUMO

AIMS/HYPOTHESIS: Ethnic representativeness of participant enrolment in diabetes RCTs involving multiple ethnicities remains unknown. The aims of this study were to evaluate the status and temporal trend of ethnic representativeness in enrolment to diabetes RCTs, and to assess under-enrolment of non-white ethnic groups and explore trial characteristics associated with under-enrolment. METHODS: We conducted a chronological survey by systematically searching the literature to include eligible RCTs published between January 2000 and December 2020. We assessed temporal trends in enrolment of ethnic groups in the included trials. Univariable logistic regression was used to explore the association between trial characteristics and under-enrolment of non-white groups, using a participant to prevalence ratio of <0.8 to define under-enrolment. This study was registered in PROSPERO (CRD42021229100). RESULTS: We included 405 RCTs for analysis (327 multi-country trials, 69 conducted in the USA and nine conducted in the UK). The median enrolment rate of all non-white groups was 24.0% in the overall RCTs. Trials conducted in the USA and the UK had median enrolment rates of 29.0% and 12.0% for all non-white groups, respectively. There was a temporal trend towards increased participation of non-white ethnic groups in the overall RCTs; however, no significant improvement over time was found in the US or UK trials. Non-white groups were under-enrolled in most included trials: 62.3% (43/69) in US trials and 77.8% (7/9) in UK trials. The US trials with a high female proportion were associated with lower odds of under-enrolment of all non-white groups (OR 0.22; 95% CI 0.07, 0.65), while trials receiving funding from industry showed increased odds of under-enrolment (OR 4.64; 95% CI 1.50, 14.35). Outpatient enrolment and intervention duration were significantly associated with under-enrolment of Black participants. Only a small proportion of trials reported subgroup results or explored the effect modification by ethnicity. CONCLUSIONS/INTERPRETATION: A temporal trend towards increased non-white ethnic enrolment was found in diabetes RCTs globally, but not in the USA or the UK. Non-white ethnic groups were under-represented in the majority of diabetes trials conducted in the USA and the UK. Some trial characteristics may be associated with non-white under-enrolment in diabetes trials. These findings provide some evidence for non-white ethnic representativeness in diabetes trials over the past two decades, and highlight the need for more effective strategies and endeavours to alleviate under-enrolment of non-white ethnic groups.


Assuntos
Diabetes Mellitus , Etnicidade , Diabetes Mellitus/tratamento farmacológico , Feminino , Humanos , Inquéritos e Questionários
10.
BMC Med ; 20(1): 294, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36109742

RESUMO

BACKGROUND: Lack of representativeness in Black, Indigenous, and People of Colour (BIPOC) enrollment could compromise the generalizability of study results and health equity. This study aimed to examine trends in BIPOC groups enrollment in diabetes randomized controlled trials (RCTs) and to explore the association between trial factors and high-enrollment of BIPOC groups. METHODS: We systematically searched the literature on large diabetes RCTs with a sample size of ≥ 400 participants published between 2000 and 2020. We assessed temporal trends in enrollment of racial and ethnic groups in the included trials. Logistic and linear regression analyses were used to explore the relationship between trial factors and the high-enrollment defined by median enrollment rate. RESULTS: A total of 405 RCTs were included for analyses. The median enrollment rate of BIPOC groups was 24.0%, with 6.4% for the Black group, 11.2% for Hispanic, 8.5% for Asian, and 3.0% for other BIPOC groups respectively. Over the past 20 years, the BIPOC enrollment showed an increased trend in the diabetes RCTs, ranging from 20.1 to 28.4% (P for trend = 0.041). A significant trend towards increased enrollment for Asian group was observed. We found that weekly or daily intervention frequency (OR = 0.48, 95% CI: 0.26, 0.91) and duration of intervention > 6.5 month (OR = 0.59, 95% CI: 0.37, 0.95) were significantly related to decreased odds of high-enrollment, while type 2 diabetes (OR = 1.44, 95% CI: 1.04, 1.99) was associated with high-enrollment of BIPOC groups. CONCLUSIONS: The enrollment of BIPOC was found to increase in large diabetes RCTs over the past two decades; some trial factors may be significantly associated with BIPOC enrollment. These findings may highlight the importance of enrollment of BIPOC groups and provide insights into the design and implementation of future clinical trials in diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Etnicidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra
11.
Bull Environ Contam Toxicol ; 110(1): 19, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36539543

RESUMO

Soil Cd contamination to wheat raise wide concerns over food safety. It is essential to find the key factors affecting Cd accumulation in wheat and to establish a predictive model. The effects of pH, Zn, Ca, and DOM on the accumulation of Cd in wheat were investigated using hydroponic experiments. The results showed that Zn was the most important factor inhibiting Cd uptake in wheat. Models were developed to predict the Cd contents in wheat tissues based on the ion concentration. Meanwhile, the available Cd contents in soil were predicted using a geochemical multi-surface model (MSM) which is suitable for various soils and conditions. The combination of the hydroponic accumulation model and MSM exhibits good predictions of wheat-Cd (R2 = 0.822-0.862, RMSE = 0.317-0.533). The results of this study can quantitatively predict the accumulation of Cd in wheat and provide a reference for soil remediation and safe wheat production.


Assuntos
Poluentes do Solo , Solo , Solo/química , Cádmio/análise , Triticum/química , Fertilizantes , Poluentes do Solo/análise , Zinco
12.
Acta Pharmacol Sin ; 42(11): 1930-1941, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34462563

RESUMO

Intracellular Staphylococcus aureus (S. aureus) often causes clinical failure and relapse after antibiotic treatment. We previously found that 20(S)-ginsenoside Rh2 [20(S)-Rh2] enhanced the therapeutic effect of quinolones in a mouse model of peritonitis, which we attributed to the increased concentrations of quinolones within bacteria. In this study, we investigated the enhancing effect of 20(S)-Rh2 on levofloxacin (LVF) from a perspective of intracellular bacteria. In S. aureus 25923-infected mice, coadministration of LVF (1.5 mg/kg, i.v.) and 20(S)-Rh2 (25, 50 mg/kg, i.g.) markedly increased the survival rate, and decreased intracellular bacteria counts accompanied by increased accumulation of LVF in peritoneal macrophages. In addition, 20(S)-Rh2 (1, 5, 10 µM) dose-dependently increased the uptake and accumulation of LVF in peritoneal macrophages from infected mice without drug treatment. In a model of S. aureus 25923-infected THP-1 macrophages, we showed that 20(S)-Rh2 (1, 5, 10 µM) dose-dependently enhanced the intracellular antibacterial activity of LVF. At the cellular level, 20(S)-Rh2 increased the intracellular accumulation of LVF by inhibiting P-gp and BCRP. PK-PD modeling revealed that 20(S)-Rh2 altered the properties of the cell but not LVF. At the subcellular level, 20(S)-Rh2 did not increase the distribution of LVF in lysosomes but exhibited a stronger sensitizing effect in acidic environments. Molecular dynamics (MD) simulations showed that 20(S)-Rh2 improved the stability of the DNA gyrase-LVF complex in lysosome-like acidic conditions. In conclusion, 20(S)-Rh2 promotes the cellular pharmacokinetics and intracellular antibacterial activities of LVF against S. aureus through efflux transporter inhibition and subcellular stabilization, which is beneficial for infection treatment.


Assuntos
Antibacterianos/farmacocinética , Ginsenosídeos/farmacocinética , Líquido Intracelular/metabolismo , Levofloxacino/farmacocinética , Staphylococcus aureus/metabolismo , Frações Subcelulares/metabolismo , Animais , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Feminino , Humanos , Líquido Intracelular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana/métodos , Staphylococcus aureus/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos , Células THP-1
13.
Andrologia ; 53(6): e14060, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33782980

RESUMO

Nonalcoholic fatty liver disease (NAFLD), the liver component of metabolic syndrome, is considered to be associated with high risk of prostatic diseases but a systematic review has not been conducted. Under a comprehensive review of the eligible clinical studies, a potential positive association between NAFLD and benign prostatic hyperplasia/prostate cancer (BPH/PCa) has been postulated. Insulin resistance and metabolic aberrations are considered to be the potential mechanism for such association. However, the relationship between NAFLD and other prostatic diseases, that is, prostatic inflammation and lower urinary tract symptoms, seems vague due to limited relevant studies in the literatures. The present review highlights that clinicians should be conscious of the detrimental effect of NAFLD on the development of BPH and PCa.


Assuntos
Resistência à Insulina , Sintomas do Trato Urinário Inferior , Hepatopatia Gordurosa não Alcoólica , Hiperplasia Prostática , Prostatite , Humanos , Sintomas do Trato Urinário Inferior/epidemiologia , Sintomas do Trato Urinário Inferior/etiologia , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hiperplasia Prostática/complicações , Hiperplasia Prostática/epidemiologia
14.
Org Biomol Chem ; 18(19): 3767, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32377659

RESUMO

Correction for 'Nickel-catalyzed cyanation of phenol derivatives activated by 2,4,6-trichloro-1,3,5-triazine' by Liang Wang, et al., Org. Biomol. Chem., 2018, 16, 4816-4820, DOI: 10.1039/C8OB01034J.

15.
Sensors (Basel) ; 20(16)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785187

RESUMO

Error-related potentials (ErrPs) have provided technical support for the brain-computer interface. However, different visual stimulations may affect the ErrPs, and furthermore, affect the error recognition based on ErrPs. Therefore, the study aimed to investigate how people respond to different visual stimulations (static and dynamic) and find the best time window for different stimulation. Nineteen participants were recruited in the ErrPs-based tasks with static and dynamic visual stimulations. Five ErrPs were statistically compared, and the classification accuracies were obtained through linear discriminant analysis (LDA) with nine different time windows. The results showed that the P3, N6, and P8 with correctness were significantly different from those with error in both stimulations, while N1 only existed in static. The differences between dynamic and static errors existed in N1 and P2. The highest accuracy was obtained in the time window related to N1, P3, N6, and P8 for the static condition, and in the time window related to P3, N6, and P8 for the dynamic. In conclusion, the early components of ErrPs may be affected by stimulation modes, and the late components are more sensitive to errors. The error recognition with static stimulation requires information from the entire epoch, while the late windows should be focused more within the dynamic case.


Assuntos
Interfaces Cérebro-Computador , Encéfalo/fisiologia , Eletroencefalografia , Estimulação Luminosa , Humanos
16.
Sensors (Basel) ; 20(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218118

RESUMO

In this paper, a piezoelectric tactile sensor for detecting tissue stiffness in robot-assisted minimally invasive surgery (RMIS) is proposed. It can detect the stiffness not only when the probe is normal to the tissue surface, but also when there is a contact angle between the probe and normal direction. It solves the problem that existing sensors can only detect in the normal direction to ensure accuracy when the degree of freedom (DOF) of surgical instruments is limited. The proposed senor can distinguish samples with different stiffness and recognize lump from normal tissue effectively when the contact angle varies within [0°, 45°]. These are achieved by establishing a new detection model and sensor optimization. It deduces the influence of contact angle on stiffness detection by sensor parameters design and optimization. The detection performance of the sensor is confirmed by simulation and experiment. Five samples with different stiffness (including lump and normal samples with close stiffness) are used. Through blind recognition test in simulation, the recognition rate is 100% when the contact angle is randomly selected within 30°, 94.1% within 45°, which is 38.7% higher than the unoptimized sensor. Through blind classification test and automatic k-means clustering in experiment, the correct rate is 92% when the contact angle is randomly selected within 45°. We can get the proposed sensor can easily recognize samples with different stiffness with high accuracy which has broad application prospects in the medical field.


Assuntos
Procedimentos Cirúrgicos Robóticos/instrumentação , Instrumentos Cirúrgicos , Tato , Simulação por Computador , Humanos
17.
Chemistry ; 25(38): 8975-8981, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31021424

RESUMO

Lithium-ion batteries (LIBs) are one of the most significant energy storage devices applied in power supply facilities. However, a huge number of spent LIBs would bring harmful resource waste and environmental hazards. In this study, a benign hydrometallurgical method using phytic acid as precipitant is proposed to recover useful metallic Mn ions from spent LiMn2 O4 batteries. Besides Mn-based cathodes, this recovery process is also applicable for other commercial batteries. More importantly, for the first time, the as-obtained manganous complex is employed as a nanofiller in a polyethylene oxide matrix to largely improve Li+ conductivity and transference number. As a result, when applied in all-solid-state lithium batteries, high capacity and outstanding cyclic stability are achieved with capacity retention of 86.4 % after 60 cycles at 0.1 C. The recovery of spent lithium batteries not only has benefits for the environment and resources, but also shows great potential application in all-solid-state lithium batteries, which opens up a costless and efficient circulation pathway for clean and reliable energy storage systems.

18.
Chemistry ; 25(66): 15173-15181, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31544301

RESUMO

Owing to low ion/electron conductivity and large volume change, transitional metal dichalcogenides (TMDs) suffer from inferior cycle stability and rate capability when used as the anode of lithium-ion batteries (LIBs). To overcome these disadvantages, amorphous molybdenum sulfide (MoSx ) nanospheres were prepared and coated with an ultrathin carbon layer through a simple one-pot reaction. Combining X-ray photoelectron spectroscopy (XPS) with theoretical calculations, MoSx was confirmed as having a special chain molecular structure with two forms of S bonding (S2- and S2 2- ), the optimal adsorption sites of Li+ were located at S2 2- . As a result, the MoSx electrode exhibits superior cycle and rate capacities compared with crystalline 2H-MoS2 (e.g., delivering a high capacity of 612.4 mAh g-1 after 500 cycles at 1 A g-1 ). This is mainly attributed to more exposed active S2 2- sites for Li storage, more Li+ transfer pathways for improved ion conductivity, and suppressed electrode structure pulverization of MoSx derived from the inherent chain-like molecular structure. Quantitative charge storage analysis further demonstrates the improved pseudocapacitive contribution of amorphous MoSx induced by fast reaction kinetics. Moreover, the morphology contrast after cycling demonstrates the dispersion of active materials is more uniform for MoSx than 2H-MoS2 , suggesting the MoSx can well accommodate the volume stress of the electrode during discharging. Through regulating the molecular structure, this work provides an effective targeted strategy to overcome the intrinsic issues of TMDs for high-performance LIBs.

19.
BMC Cardiovasc Disord ; 19(1): 233, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640555

RESUMO

BACKGROUND: Ventricular arrhythmias (VAs) arising from the origin above pulmonary valve lack comprehensive investigation. This study aimed to disclose the characteristics and radiofrequency catheter ablation (RFCA) outcomes for those VAs. METHODS: One hundred six VAs arising from the region above pulmonary valve treated with RFCA were included in this study. RESULTS: Seventy-five cases were identified in the pulmonary sinus cusps (PSCs, 32 in left sinus cusp (PLC), 15 in right (PRC), 28 in anterior (PAC)) and 31 cases were in the main stem of pulmonary artery (MSPA, 18 above PLC (LMSPA), 3 above PRC (RMSPA), 10 above PAC (AMSPA)). Compared with PSCs VAs, MSPA VAs exhibited a higher R wave amplitude in the inferior leads, a total inferior R amplitude > 5.1 mV predicting MSPA origins. LMSPA, RMSPA and AMSPA VAs resembled PLC, PRC and PAC VAs in electrocardiographic characteristics respectively. No electrophysiological differences were found between PSCs and MSPA VAs. The irrigated-up catheter and R0 Swartz long sheath were more utilized for ablation of PSCs VAs than for MSPA VAs. All these VAs were successfully eliminated by RFCA. CONCLUSION: VAs arising from the origin above pulmonary valve were common. Based on certain electrocardiographic characteristics, they could be roughly located, which contributed to an effective RFCA.


Assuntos
Ablação por Cateter , Artéria Pulmonar/cirurgia , Valva Pulmonar , Taquicardia Ventricular/cirurgia , Complexos Ventriculares Prematuros/cirurgia , Adulto , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/fisiopatologia , Valva Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/fisiopatologia , Resultado do Tratamento , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/fisiopatologia
20.
J Environ Manage ; 241: 319-327, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31015082

RESUMO

Engineered nanoparticles (NPs) are now used as additives in pesticides and fungicides and as novel fertilizers in agriculture so there is an urgent need to explore their effects on crop yield and quality in a full life cycle study. In the present study, three widely used NPs (TiO2, Fe2O3 and CuO NPs applied at doses of 50 and 500 mg/kg) were selected to investigate their long-term impact on wheat growth. TiO2 NPs did not affect the growth and development of wheat, but Fe2O3 NPs promoted wheat precocity and CuO NPs inhibited the growth and development of the wheat grains. The Cu content in grains treated with CuO NP increased by 18.84%-30.45% compared with the control. However, the contents of Fe and Zn were both significantly lower in the CuO NP treatments. Univariate and multivariate analyses were used to analyze the effect of different NPs on the composition of amino acids in wheat grains. Exposure to TiO2 NPs at dose of 500 mg/kg increased the overall amino acid nutrition in the edible portion of wheat. Fe2O3 NPs at both doses increased the contents of cysteine (Cys) and tyrosine (Tyr). The addition of CuO NPs reduced the level of some essential amino acids in wheat grains, isoleucine (Ile), leucine (Leu), threonine (Thr) and histidine (His). Overall, evaluation of the potential impacts of metal-based NPs on the nutritional quality of wheat grains could provide important information for their safe use when incorporated into agrichemicals in sustainable agriculture.


Assuntos
Nanopartículas Metálicas , Triticum , Aminoácidos , Cobre , Metais , Óxidos
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