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1.
ACS Nano ; 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34734696

RESUMO

The binary compound of GeTe emerging as a potential medium-temperature thermoelectric material has drawn a great deal of attention. Here, we achieve ultralow lattice thermal conductivity and high thermoelectric performance in In and a heavy content of Cu codoped GeTe thermoelectrics. In dopants improve the density of state near the surface of Femi of GeTe by introducing resonant levels, producing a sharp increase of the Seebeck coefficient. In and Cu codoping not only optimizes carrier concentration but also substantially increases carrier mobility to a high value of 87 cm2 V-1 s-1 due to the diminution of Ge vacancies. The enhanced Seebeck coefficient coupled with dramatically enhanced carrier mobility results in significant enhancement of PF in Ge1.04-x-yInxCuyTe series. Moreover, we introduce Cu2Te nanocrystals' secondary phase into GeTe by alloying a heavy content of Cu. Cu2Te nanocrystals and a high density of dislocations cause strong phonon scattering, significantly diminishing lattice thermal conductivity. The lattice thermal conductivity reduced as low as 0.31 W m-1 K-1 at 823 K, which is not only lower than the amorphous limit of GeTe but also competitive with those of thermoelectric materials with strong lattice anharmonicity or complex crystal structures. Consequently, a high ZT of 2.0 was achieved for Ge0.9In0.015Cu0.125Te by decoupling electron and phonon transport of GeTe. This work highlights the importance of phonon engineering in advancing high-performance GeTe thermoelectrics.

2.
J Healthc Eng ; 2021: 6896929, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804457

RESUMO

There are numerous uncertainties associated with environmental health risk assessment (EHRA), and it is unavoidable to apply the best models and information available to save human lives. The EHRA is a method for determining the type and likelihood of adverse health effects on people who are exposed to chemicals in the workplace. To address the environmental health problems caused by harmful gas leakage and water pollution generated by the coastal regional chemical industry, a novel EHRA model for the coastal chemical industry has been developed. The premise of the Gauss plume diffusion model is used to define the model's parameters and the evaluation criterion for harmful gas concentration health risk. The EHRA model is evaluated against the leakage of harmful gases and consists of three steps. The first step is to identify the threat posed by the chemical industry in the coastal region; the second step is to quantify the risk; the third step is to develop a model for assessing water-related environmental health risk. The water-related environmental health assessor analyzes the pollutant variables and parameters of the assessment model to estimate the health risk caused by dangerous compounds in the water, using the assessment model of chemical carcinogen health risk and noncarcinogen health risk Type B. The experiments' findings suggest that the model can effectively assess the dangers to human health from hazardous gases and heavy metals in the water bodies of chemical factories in coastal communities.

3.
J Org Chem ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34818024

RESUMO

Diimine (HN═NH) is a strong reducing agent, but the efficiency of diimine oxidized from hydrazine hydrate or its derivatives is still not good enough. Herein, we report an in situ neocuproine-copper complex formation method. The redox potential of this complex enable it can serve as an ideal redox catalyst in the synthesis of diimine by oxidation of hydrazine hydrate, and we successfully applied this technique in the reduction of alkynes. This reduction method displays a broad functional group tolerance and substrate adaptability as well as the advantages of safety and high efficiency. Especially, nitro, benzyl, boc, and sulfur containing alkynes can be reduced to the corresponding alkanes directly, which provides a useful complementary method to traditional catalytic hydrogenation. Besides, we applied this method in the preparation of the Alzheimer's disease drug CT-1812 and studied the mechanism.

5.
Biomed Opt Express ; 12(9): 5614-5628, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34692204

RESUMO

Expansion microscopy enables conventional diffraction limit microscopy to achieve super-resolution imaging. However, the enlarged tissue lacks an objective lens with sufficient working distance that can image tissues with whole-brain-scale coverage. Here, we present expansion tomography (ExT) to solve this problem. We have established a modified super-absorbent hydrogel (ExT gel) that possesses high mechanical strength and enables serial sectioning. ExT gel enables tissue and cell imaging and is compatible with various fluorescent labeling strategies. Combining with the high-throughput light-sheet tomography (HLTP) system, we have shown the capability of large volume imaging with nanoscale resolution of mouse brain intact neuronal circuits. The ExT method would allow image samples to support super-resolution imaging of intact tissues with virtually unlimited axial extensions.

6.
J Microsc ; 284(3): 256-265, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34633086

RESUMO

Partially missing bands in the preset region for Hough transform might strongly affect the accuracy of indexing Kikuchi patterns and reduce the quality of electron backscatter diffraction (EBSD) maps. This paper proposes a novel local band detection method for such kind of low-quality patterns. The approach involves rotating bands to vertical direction, detecting the local line segments through calculating the largest horizontal average grey gradient with a constant interval of 400 pixels in vertical direction, and applying Hough transform as well as weighted averaging to these line clusters to unify the edges of Kikuchi band. Therefore, even if only part of a Kikuchi band is visible, the entire band can also be accurately extracted. The average interplanar angle error obtained by the proposed method is approximately 29.0% less than those obtained by Hough transform-based technique. Moreover, the comparison of mean angular deviation (MAD) is also discussed. The average MAD of this method is about 38.5% lower than that of Hough transform-based technique. Consequently, the local Kikuchi band detection method is expected to be used for post-processing and re-indexing the EBSD low-quality patterns.

7.
Clin Nephrol ; 96(6): 317-327, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34605399

RESUMO

OBJECTIVE: To identify and analyze the most prominent problems of peritoneal dialysis (PD) patients by applying a nurse-led multidisciplinary health problem assessment tool. METHODS: 170 PD patients were recruited from the PD center of the First Affiliated Hospital of GuangXi Medical University from January 2019 to June 2019, and their information was collected from July 2019 to June 2020 through telephone interviews, Wechat interviews, outpatient visits, and home visits; their health problems were classified and analyzed with regard to physiological, psychosocial, health-related behavior, and environment categories based on the Omaha Problem Classification System, and their knowledge, behavior, and status related to these problems were evaluated by the Omaha Knowledge-Behavior-Status Scale. RESULTS: 165 of the eligible patients completed the follow-up, and their ten most prominent health problems were "Income", "Social contact", "Pain", "Neuro-musculo-skeletal function", "Digestion-hydration" and "Edema", "Nutrition", "Physical activity", "Fluid and diet restriction", and "Symptom management". As for the Knowledge-Behavior-Status scale, they got the lowest scores in knowledge of "Symptom management", behavior of "Fluid and diet restriction" and Status of "Nutrition", while they scored the best in knowledge of "Nutrition" and "Edema", behavior of "Income" and "Pain", and Status of "Pain" and "Edema". CONCLUSION: The multidisciplinary problem assessment tool based on the Omaha Problem Classification System serves as an effective and instructive tool to identify the prominent health problems of PD patients and provides a basis for the development of subsequent targeted interventions.


Assuntos
Papel do Profissional de Enfermagem , Diálise Peritoneal , China , Estudos Transversais , Humanos , Estado Nutricional , Diálise Peritoneal/efeitos adversos
8.
Waste Manag ; 135: 428-436, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34619624

RESUMO

Fly ash from coal-fired power plants has become the world's largest solid waste pollutant. The mechanochemical (MC) method used as a non-thermal method shows good stability to heavy metals in soil and municipal solid waste incineration (MSWI) fly ash. It is first uesd to stabilize the heavy metals in fly ash from coal-fired power plants. In this paper, dry milling and wet milling MC methods were carried out on fly ash from a 300 MW supercritical circulating fluidized bed (CFB) boiler. The relative leaching rate (RLR) is defined to indicate the degree of leaching. Experimental results show that after mechanochemical treatment for 10 h, the RLRs of Cu, Cr, Pb, Zn, Cd, and Ni by dry milling decrease by 52.10%, 70.16%, 89.80%, 22.97%, 3.15%, and 23.49% respectively, and the RLRs of Cu, Cr, Pb, Zn, Cd and Ni by wet milling decrease by 58.11%, 70.92%, 89.64%, 23.26%, 10.59%, and 30.77% respectively. Compared with dry milling, the fly ash particle size is smaller after wet milling, indicating that the presence of water will weaken the agglomeration of fine particles. A continuous extraction experiment shows that the water-and acid-soluble fraction of the six heavy metals in fly ash can be reduced by dry or wet milling, and the residual fraction can be increased.


Assuntos
Cinza de Carvão , Metais Pesados , Carbono , Carvão Mineral , Cinza de Carvão/análise , Incineração , Metais Pesados/análise , Material Particulado , Centrais Elétricas , Resíduos Sólidos
10.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443340

RESUMO

The oat ß-glucan (OG) was added into set-type yogurt as a functional ingredient, in order to evaluate effects on the rheological characteristics and microstructure of set-type yogurt. When the OG concentration increased from 0 to 0.3%, the WHC gradually increased. At 0.3% OG, the set-type yogurt had the highest WHC of 94.67%. Additionally, the WHC continuously decreased, reaching the lowest WHC (about 80%) at 0.5% OG. When 0.3% OG was added, the highest score of sensory evaluation was about 85. The rheological result showed that the fermentation process went through the changes as follows: solid → liquid → solid → liquid. The addition of 0.3% OG decreased the fermentation time of set-type yogurt by about 16 min, making yogurt more inclined to be liquid. The acidity of set-type yogurt with OG was slightly higher. The result of microstructure showed that the addition of OG destroyed the three-dimensional network structure of yogurt, and some spherical aggregate particles could be clearly observed at 0.3% OG. Overall, this study provided a theoretical basis for the application of OG in set-type yogurt.


Assuntos
Avena/química , Reologia , Iogurte/análise , beta-Glucanas/farmacologia , Fermentação/efeitos dos fármacos
11.
J Microsc ; 284(3): 233-243, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34383320

RESUMO

An electron backscatter diffraction device is an important accessory for a scanning electron microscope and can provide crystal structure orientation and phase content data through analysis of electron backscatter diffraction patterns. The acquisition of these data depends on pattern indexing, including interplanar angle calculation and crystal plane indexation. The coordinates of the source point are key points for interplanar angle calculation, and they vary with the movement of the incident beam. In this study, we first combined the grey gradient calculation with screen moving method to achieve accurate positioning of source point and obtained coordinates of source point with sub-pixel precision. The errors of three coordinates were 0.07%, 0.06% and 0.04%, respectively. By using this coordinate of source point to conduct interplanar angle calculation the maximum error was 0.53°, which was a good proof of the accuracy of source point positioning. Then we established the relationship between source point coordinates variation and incident beam movement. Coordinates can be given out based on the displacement of beam directly. And to illustrate the accuracy, interplanar angle calculation was performed and the maximum error was 0.81°. This means that the relationship between variation of source point coordinates and beam movement is highly accurate.

12.
J Immunol Res ; 2021: 9998517, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285925

RESUMO

Patients who survive the acute phase of sepsis can progress to persistent inflammation, immunosuppression, and catabolism syndrome (PICS), which usually results in extended recovery periods and multiple complications. Alpinetin is a flavonoid isolated from Alpinia katsumadai Hayata that has been demonstrated to have anti-inflammatory, antibacterial, and antioxidant activities. The aim of this study was to investigate whether the administration of alpinetin could attenuate PICS in a septic mouse model. Mice were randomly divided into four groups: the (1) sham-operated group, (2) sham+alpinetin (1 mg/kg intravenously infused for once per day after sham operation), (3) cecal ligation and puncture (CLP), and (4) CLP+alpinetin (50 mg/kg intravenously infused for once per day after CLP). Eight days after sham operation or CLP surgery, mice were euthanized for subsequent examination. Alpinetin significantly improved the survival of septic mice. Also, it attenuated the CLP-induced persistent inflammation, immunosuppression, and catabolism syndrome. The level of plasma proinflammatory cytokines and apoptosis of T lymphocytes were obviously decreased by alpinetin as well. Moreover, oxidative stress in the organs was compelling lower in the alpinetin-treated CLP mice. In this clinically relevant model of sepsis, alpinetin ameliorates CLP-induced organ dysfunction and improves the likelihood of survival, possibly through suppressing the inflammatory response, oxidative stress, and apoptosis. These findings suggested that alpinetin could be a potential novel therapeutic approach to prevent sepsis-induced PICS.

13.
RNA Biol ; : 1-12, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34314293

RESUMO

RNA editing generates genetic diversity in mammals by altering amino acid sequences, miRNA targeting site sequences, influencing the stability of targeted RNAs, and causing changes in gene expression. However, the extent to which RNA editing affect gene expression via modifying miRNA binding site remains unexplored. Here, we first profiled the dynamic A-to-I RNA editome across tissues of Duroc and Luchuan pigs. The RNA editing events at the miRNA binding sites were generated. The biological function of the differentially edited gene in skeletal muscle was further characterized in pig muscle-derived satellite cells. RNA editome analysis revealed a total of 171,909 A-to-I RNA editing sites (RESs), and examination of its features showed that these A-to-I editing sites were mainly located in SINE retrotransposons PRE-1/Pre0_SS element. Analysis of differentially edited sites (DESs) revealed a total of 4,552 DESs across tissues between Duroc and Luchuan pigs, and functional category enrichment analysis of differentially edited gene (DEG) sets highlighted a significant association and enrichment of tissue-developmental pathways including TGF-beta, PI3K-Akt, AMPK, and Wnt signaling pathways. Moreover, we found that RNA editing events at the miRNA binding sites in the 3'-UTR of HSPA12B mRNA could prevent the miRNA-mediated mRNA downregulation of HSPA12B in the muscle-derived satellite (MDS) cell, consistent with the results obtained from the Luchuan skeletal muscle. This study represents the most systematic attempt to characterize the significance of RNA editing in regulating gene expression, particularly in skeletal muscle, constituting a new layer of regulation to understand the genetic mechanisms behind phenotype variance in animals.

14.
J Hazard Mater ; 420: 126583, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34252656

RESUMO

A novel and efficient adsorbent (TM-MoSe2, TM = Fe, Co, Ni) for mercury removal was developed and studied. The adsorption of mercury species (Hg0, HgCl, and HgCl2) and the oxidation of Hg0 by HCl on TM-MoSe2 (001) surface were explored at molecular level by density functional theory (DFT). The results shown that the Hg0 adsorption capacity of MoSe2 was improved by the doping of Fe/Co/Ni, which was also confirmed by experiments. The initial Hg0 removal efficiency of MoSe2-based adsorbents reached 96.4-100.0%. In addition, HgCl was mainly adsorbed on TM-MoSe2 (001) surface in the form of dissociation. The escape of Hg atom from HgCl resulted in the release of Hg0 again. However, HgCl2 could be fixed well on the surface of adsorbent through molecular adsorption or dissociative adsorption. For the oxidation process of Hg0 by HCl, it abided with the Langmuir-Hinshelwood mechanism. In comparison with direct oxidation (Hg → HgCl2), two-step pathway (Hg → HgCl → HgCl2) was an achievable reaction route with lower energy. Furthermore, the Hg → HgCl process was the rate-limiting step of the two-step pathway. The proposed adsorption and oxidation mechanism of mercury species on TM-MoSe2 (001) provide advanced strategies on the development of adsorbents for industrial mercury removal.

15.
Cancer Med ; 10(13): 4240-4249, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34117733

RESUMO

PURPOSE: To investigate whether preoperative histogram parameters of dynamic contrast-enhanced MRI (DCE-MRI) can assess the expression of Ki-67 in prostate cancer (PCa). MATERIALS AND METHODS: A consecutive series of 76 patients with pathology-proven PCa who underwent routine DCE-MRI scans were retrospectively recruited. Quantitative parameters including the volume transfer constant (Ktrans ), rate contrast (Kep ), extracellular-extravascular volume fraction (Ve ), and plasma volume (Vp ) by outlining the three-dimensional volume of interest (VOI) of all lesions were processed. Then, the histogram analyses of these quantitative parameters were performed. The Spearman rank correlation analysis was used to evaluate the correlation of these parameters and Ki-67 expression of PCa. Receiver operating characteristic (ROC) curve analysis was adopted to evaluate the efficacy of these quantitative histogram parameters in identifying high Ki-67 expression from low Ki-67 expression of PCa. RESULTS: Eighty-eight PCa lesions were enrolled in this study, including 31 lesions with high Ki-67 expression and 57 lesions with low Ki-67 expression. The median, mean, 75th percentile, and 90th percentile derived from Ktrans and Kep had a moderately positive correlation with Ki-67 expression (r = 0.361-0.450, p < 0.05), in which both the median and mean of Ktrans had the highest positive correlation (r = 0.450, p < 0.05). The diagnostic efficacy of the Ktrans median, mean, 75th percentile, and 90th percentile, along with the Kep -based median and mean was assessed by the ROC curve. The area under the curve (AUC) of the mean for Ktrans was the highest (0.826). When the cut-off of the mean for Ktrans was ≥0.47/min, its Youden index, sensitivity, and specificity were 0.625, 0.871, and 0.754, respectively. The AUC of the median of Kep was the lowest (0.772). CONCLUSION: The histogram of DCE-MRI quantitative parameters is correlated with Ki-67 expression, which has the potential to noninvasively assess the expression of Ki-67 with patients of PCa.

16.
J Microsc ; 283(3): 192-201, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33984152

RESUMO

Symmetry analysis of the Kikuchi pattern is helpful to determine the crystal structure, and can significantly reduce the screening range of phase identification, thereby improving the accuracy and reliability of phase identification in electron backscatter diffraction (EBSD). Accurately identifying the symmetry axis from the Kikuchi pattern is the primary task of symmetry analysis. In this study, a new method was proposed to identify symmetry axes in Kikuchi patterns with the aid of reciprocal vectors. Taking the Kikuchi patterns of single-crystal silicon as a typical example, a method for drawing reciprocal vectors after strict projection correction is introduced. The complex task of identifying the symmetry axis is transformed into an intuitive judgment of the geometric relationship between reciprocal vectors, thus greatly simplifying the process. This method successfully elucidated information on six Kikuchi poles in three single-crystal silicon Kikuchi patterns, including 3-fold axes, 4-fold axes and asymmetric axes. The method can also distinguish between a 3-fold axis and an analogous 3-fold axis despite their only slight differences.

17.
Adv Sci (Weinh) ; 8(8): 2002051, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33898166

RESUMO

It remains a daunting task to quantify the configurational entropy of a material from atom-revolved electron microscopy images and correlate the results with the material's lattice thermal conductivity, which strides across statics, dynamics, and thermal transport of crystal lattice over orders of magnitudes in length and time. Here, a proof-of-principle study of atomic-scale visualization and quantification of configurational entropy in relation to thermal conductivity in single crystalline trigonal GeSb2Te4 (aka t-GeSb2Te4) with native atomic site disorder is reported. A concerted effort of large t-GeSb2Te4 single crystal growth, in-lab developed analysis procedure of atomic column intensity, the visualization and quantification of configurational entropy including corresponding modulation, and thermal transport measurements enable an entropic "bottom-up" perspective to the lattice thermal conductivity of t-GeSb2Te4. It is uncovered that the configurational entropy increases phonon scattering and reduces phonon mean free path as well as promotes anharmonicity, thereby giving rise to low lattice thermal conductivity and promising thermoelectric performance. The current study sheds lights on an atomic scale bottom-up configurational entropy design in diverse regimes of structural and functional materials research and applications.

18.
ACS Nano ; 15(5): 8204-8215, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33852270

RESUMO

Polycrystalline SnSe materials with ZT values comparable to those of SnSe crystals are greatly desired due to facile processing, machinability, and scale-up application. Here manipulating interatomic force by harnessing lattice strains was proposed for achieving significantly reduced lattice thermal conductivity in polycrystalline SnSe. Large static lattice strain created by lattice dislocations and stacking faults causes an effective shortening in phonon relaxation time, resulting in ultralow lattice thermal conductivity. A combination of band convergence and resonance levels induced by Ga incorporation contribute to a sharp increase of Seebeck coefficient and power factor. These lead to a high thermoelectric performance ZT ∼ 2.2, which is a record high ZT reported so far for solution-processed SnSe polycrystals. Besides the high peak ZT, a high average ZT of 0.72 and outstanding thermoelectric conversion efficiency of 12.4% were achieved by adopting nontoxic element doping, highlighting great potential for power generation application at intermediate temperatures. Engineering lattice strain to achieve ultralow lattice thermal conductivity with the aid of band convergence and resonance levels provides a great opportunity for designing prospective thermoelectrics.

19.
PLoS One ; 16(3): e0247187, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33705415

RESUMO

Household time-use patterns are expected to reflect each household member's daily activity participation and duration with intra-household interactions constrained by multiple budgets. Among various activities, the allocated activity derived from undertaking a household task is studied relatively less in the literature. Who will take an allocated activity is a discrete choice problem of household task assignment, and once a household member is assigned with one household task, other members will have more time to do other activities. To better understand household time-use patterns affected by household task assignment, this paper proposed a joint household-level multiple discrete-continuous extreme value-multinomial logit (MDCEV-MNL) model with multiple constraints. The Karush-Kuhn-Tucker (KKT) method combined with the simulation-based maximum likelihood estimation method is proposed to estimate the proposed model. Based on the household activity-travel data from Beijing of China, the proposed model is customized to explore elderly couples' time-use patterns with intra-household interactions affected by household task assignment. Following the findings, policy implications are suggested to build an age-friendly society.


Assuntos
Serviço de Limpeza/estatística & dados numéricos , Serviço de Limpeza/normas , Serviço de Limpeza/tendências , Idoso , Pequim , China , Simulação por Computador , Características da Família , Feminino , Humanos , Atividades de Lazer/psicologia , Masculino , Modelos Estatísticos , Cônjuges/psicologia
20.
Invest New Drugs ; 39(4): 1179-1188, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33644823

RESUMO

Background Nowadays, lung cancer seriously affects human health in the world. Therefore, it is of great significance to develop effective anti-lung cancer drugs. Methods In this work, chalcone derivative HYQ97 was designed via a molecular hybridization strategy. It was synthesized by the cycloaddition in the presence of sodium ascorbate under mild conditions. Lung cancer cell lines were cultured to investigate its antitumor effects in vitro and in vivo. Results HYQ97 inhibited the proliferation of lung cancer cell lines. Specifically, its IC50 value against lung cancer A549 cells was 74.26 nM. It could inhibit heat shock protein 90 (Hsp90) and degrade its client proteins in a dose-dependent manner. Furthermore, HYQ97 suppressed the epithelial mesenchymal transition process and induced apoptosis of A549 cells. Importantly, HYQ97 also had significant inhibitory effects on tumor growth in vivo. Conclusions Chalcone derivative HYQ97 is a promising candidate for lung cancer treatment.

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