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1.
Curr Neurovasc Res ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34538231

RESUMO

INTRODUCTION: This study aimed to investigate the clinical value of bispectral index (BIS) monitoring in assessing the consciousness and prognosis of acute cerebral infarction (ACI) patients. METHODS: In total, 64 patients who suffered from ACI with consciousness disturbance were enrolled in this study. Glasgow Coma Scale (GCS) was performed to evaluate the consciousness level of ACI patients, and BIS was used to monitor the depth of anesthesia and sedation. Then, patients were divided into good prognosis, poor prognosis and death groups according to modified Rankin score (mRS). Discrimination analysis of BIS values and GCS score for the prediction of prognosis was performed using the receiver operator characteristic (ROC) curve. RESULTS: GCS score and BIS values showed statistically significant differences among the three groups. Spearman rank correlation analysis revealed a significant positive correlation between BIS values and GCS score, while BIS values was negatively related with mRS. The ROC curve of prognosis prediction showed strong prognostic power, with area under the curves (AUCs) between 0.830 and 0.917. Moreover, the AUC of BISmean score was higher than that of BISmax, BISmin and GCS, and BISmean of 74 was the best cut-off point for good prognosis. CONCLUSION: BIS directly reflects the degree of consciousness disturbance in ACI patients, and thus accurately predicts the prognosis, indicating potential application values of BIS in clinical practice.

2.
Gene ; : 145948, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481002

RESUMO

BACKGROUNDS: To investigate associations of genetic factors and environmental factors with coronary artery disease (CAD), we collected medical reports, lifestyle details, and blood samples of 2113 individuals, and then used the polymerase chain reaction (PCR)-ligase detection reaction (LDR) to genotype the targeted 102 SNPs. METHODS: We adopted elastic net algorithm to build an association model that considered simultaneously genetic and lifestyle/clinical factors associated with CAD in Chinese Han population. RESULTS: In this study, we developed an all covariates-based model to explain the risk of CAD, which incorporated 8 lifestyle/clinical factors and a gene-score variable calculated from 3 significant SNPs (rs671, rs6751537 and rs11641677), attaining an area under the curve (AUC) value of 0.71. It is found that, in terms of genetic variants, the AA genotype of rs671 in the additive (adjusted odds ratio (OR)=2.51, p=0.008) and recessive (adjusted OR=2.12, p=0.021) models, the GG genotype of rs6751537 in the additive (adjusted OR=3.36, p=0.001) and recessive (adjusted OR=3.47, p=0.001) models, and GG genotype of rs11641677 in additive model (adjusted OR=0.39, p=0.044) was associated with increased risk of CAD. In terms of lifestyle/clinical factors, the history of hypertension (unadjusted OR=2.37, p<0.001) and dyslipidemia (unadjusted OR=1.82, p=0.007), age (unadjusted OR=1.07, p<0.001) and waist circumference (unadjusted OR=1.02, p=0.05) would significantly increase the risk of CAD, while height (unadjusted OR=0.97, p=0.006) and regular intake of chicken (unadjusted OR=0.78, p=0.008) reduced the risk of CAD. A significantinteraction was foundbetween rs671 and dyslipidemia (the relative excess risk due to interaction (RERI) = 3.36, p=0.05). CONCLUSION: In this study, we constructed an association mode and identified a set of SNPs and lifestyle/clinical risk factors of CAD in Chinese Han population. By considering both genetic and non-genetic risk factors, the built model may provide implications for CAD pathogenesis and clues for screening tool development in Chinese Han population.

3.
Inorg Chem ; 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34474565

RESUMO

Discovering high-performance near-room-temperature thermoelectric materials is extremely imperative to widen the practical application in thermoelectric power generation and refrigeration. Here, ternary Ag2Se1-xTex (x = 0.1, 0.2, 0.3, 0.4, and 0.5) materials are prepared via the wet-mechanical alloying and spark plasma sintering process to investigate their near-room-temperature thermoelectric properties. From density functional theory calculation and single-parabolic-band modeling study, we found that the reduced contribution of Se 4p orbitals to the total density of states decreases the carrier effective mass with increasing Te content, which should enhance the theoretically maximum zT. These calculation results are also verified by the experimental results. Meanwhile, complex microstructures including dislocations, nanograins, high-density boundaries, TeSe substitution, lattice distortions, and localized strain have been observed in ternary Ag2Se1-xTex. These complex microstructures strengthen phonon scattering and in turn lead to ultralow lattice thermal conductivity in the range of 0.21-0.31 W m-1 K-1 in ternary Ag2Se1-xTex at 300 K. Although the increased deformation potential suppresses the carrier mobility, benefiting from the engineered band structures and ultralow lattice thermal conductivity, a high zT of >1 can be potentially obtained in the ternary Ag2Se1-xTex with appropriate carrier concentration. This study indicates that ternary Ag2Se1-xTex is a promising candidate for near-room-temperature thermoelectric applications.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34510347

RESUMO

Improving the logistics ecological efficiency (LEE) has become a significant part of ensuring a sustainable development and tackling environmental pollution. Previous studies in the logistics industry seldom considered air pollutants and the association of spatial information. Therefore, innovatively considering SO2, NOx, and PM, this study adopted the super-SBM-undesirable model to calculate the LEE of 30 provinces in China from 2005 to 2019 and, thereafter, developed information-based matrix to explore its influencing factors by using the spatial Dubin model. The results indicated that (1) the overall LEE was low with the average of 0.657, presenting a three-stage trend of "decreasing first, then rising, and later stable," and significant regional differences with the decreasing gradient pattern of the "Eastern-Central-Western." (2) A spatial directionality distributed from the northeast to southwest and a significant spatial autocorrelation were observed. (3) The LEE had a significant positive spillover effect. Industrial structure, urbanization level, environmental regulation, and technological innovation level had a positive impact on the local LEE, and industrial structure displayed the most promoting effects. Energy intensity, economic level, energy structure, and opening level had a significant effect on the local LEE with varying degree of inhibition. Local energy intensity and environmental regulation had a positive influence on the LEE in neighboring areas, while local opening level had inhibiting effects. In addition, policy recommendations for enhancing the LEE were made.

6.
Langmuir ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469690

RESUMO

Droplet impact on a smooth solid surface at atmospheric pressure was experimentally studied and physically interpreted. A particular emphasis of the study is on the effects of liquid viscosity on the transition between droplet deposition (or droplet spreading without breakup) and droplet disintegration (including droplet splash and receding breakup). Specifically, the critical Weber number separating droplet deposition from droplet disintegration decreases and then increases with increasing Ohnesorge number (Oh). The splash in the low-Oh region and the receding breakup in the high-Oh region were analyzed qualitatively based on the unbalanced forces acting on the rim of the spreading or receding liquid film. A semiempirical correlation of droplet deposition/disintegration thresholds is proposed and well fits the experimental results from previous and present studies over a wide range of liquid viscosity.

7.
Cell Res ; 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518654

RESUMO

Intestinal stem cell (ISC) differentiation is regulated precisely by a niche in the crypt, where lymphocytes may interact with stem and transient amplifying (TA) cells. However, whether and how lymphocyte-stem/TA cell contact affects ISC differentiation is largely unknown. Here, we uncover a novel role of T cell-stem/TA cell contact in ISC fate decisions. We show that intestinal lymphocyte depletion results in skewed ISC differentiation in mice, which can be rescued by T cell transfer. Mechanistically, integrin αEß7 expressed on T cells binds to E-cadherin on ISCs and TA cells, triggering E-cadherin endocytosis and the consequent Wnt and Notch signaling alterations. Blocking αEß7-E-cadherin adhesion suppresses Wnt signaling and promotes Notch signaling in ISCs and TA cells, leading to defective ISC differentiation. Thus, αEß7+ T cells regulate ISC differentiation at single-cell level through cell-cell contact-mediated αEß7-E-cadherin adhesion signaling, highlighting a critical role of the T cell-stem/TA cell contact in maintaining intestinal homeostasis.

8.
Nano Lett ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525805

RESUMO

We report the design and synthesis of a series of three-dimensional (3D) covalent organic frameworks (COFs) as immunogenic cell death (ICD) inducers for cancer immunotherapy. Three triple-topic amine building blocks, inactive to inducing ICD, were used to construct three COFs, COF-607, COF-608, and COF-609, with outstanding ICD eliciting efficiency. Mechanism studies revealed that after linking these ICD inert monomers into the COF backbone, the optical properties of these COFs could be systematically tuned to achieve excellent reactive oxygen species (ROS) production performance. This combined with 3D cross-linked pores, mimicking lung structure, favor the exchange and diffusion of oxygen and ROS, leading to excellent inducing ICD efficacy. One member, COF-609, is capable of triggering abscopal and long-lasting immune memory effects in a mouse model of breast cancer with >95% mice survival after being treated with COF-609+αCD47 for 110 days.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34528744

RESUMO

Inspired by the nuclear pore complex (NPC), herein we have established a biomimetic high-flux protein delivery system via the selective introduction of pillar[5]arene-based host-guest system into one side of an artificial concave (hour-glass) shaped nanochannels. With a transport flux of 660 lysozymes per minute, the system provides efficient high-flux protein transport at a rate which is significantly higher than that of an unmodified nanochannel and conventional bilateral symmetrical modified nanochannels. In view of these promising results, the use of artificial nanochannels to improve protein transport not only provides a new potential chemical model for biological research and better understanding of protein transport behavior in the living systems, but also provides a high-flux protein transporter device, which may have applications in the design of protein drug release systems, protein separation systems and microfluidics in the near future.

10.
Biomed Environ Sci ; 34(9): 705-718, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34530960

RESUMO

Objective: The effects of interactions between genetic and environmental factors on the noise-induced hearing loss (NIHL) are still unclear. This study aimed to assess interactions among gene polymorphisms, noise metrics, and lifestyles on the risk of NIHL. Methods: A case-control study was conducted using 307 patients with NIHL and 307 matched healthy individuals from five manufacturing industries. General demographic data, lifestyle details, and noise exposure levels were recorded. The Kompetitive allele-specific polymerase chain reaction (KASP) was used to analyze the genotypes of 18 SNPs. Results: GMDR model demonstrated a relevant interaction between NRN1 rs3805789 and CAT rs7943316 (P = 0.0107). Subjects with T allele of rs3805789 or T allele of rs7943316 had higher risks of NIHL than those with the SNP pair of rs3805789-CC and rs7943316-AA (P < 0.05). There was an interaction among rs3805789, rs7943316, and kurtosis (P = 0.0010). Subjects exposed to complex noise and carrying both rs3805789-CT and rs7943316-TT or rs3805789-CT/TT and rs7943316-AA had higher risks of NIHL than those exposed to steady noise and carrying both rs3805789-CC and rs7943316-AA (P < 0.05). The best six-locus model involving NRN1 rs3805789, CAT rs7943316, smoking, video volume, physical exercise, and working pressure for the risk of NIHL was found to be the interaction (P = 0.0010). An interaction was also found among smoking, video volume, physical exercise, working pressure, and kurtosis (P = 0.0107). Conclusion: Concurrence of NRN1 and CAT constitutes a genetic risk factor for NIHL. Complex noise exposure significantly increases the risk of NIHL in subjects with a high genetic risk score. Interactions between genes and lifestyles as well as noise metrics and lifestyles affect the risk of NIHL.

11.
Urol Int ; : 1-9, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34492655

RESUMO

OBJECTIVE: The aim of this study was to investigate whether diagnostic ureteroscopy (URS) biopsy is unfavourable for bladder tumour recurrence in upper urinary tract urothelial carcinoma (UTUC). MATERIALS AND METHODS: We performed a retrospective analysis of 195 patients diagnosed with UTUC, who were divided into a diagnostic URS group (URS+) and a nondiagnostic URS group (URS-) according to whether diagnostic ureteroscopic biopsy was performed. A Cox regression model was used to analyse the risk factors for intravesical recurrence (IVR)-free survival (IRFS) and overall survival (OS) in UTUC after radical nephroureterectomy (RNU). Kaplan-Meier analysis was used to estimate the influence of factors on the incidence of IVR and the cumulative survival rate of UTUC. RESULTS: Patients with a maximum tumour diameter of less than 3.1 cm, low-stage tumours, and ureteral tumours were more likely to undergo diagnostic URS before radical surgery. Multivariate Cox regression analysis showed that tumour pathological stage and diagnostic ureteroscopic biopsy can be used as predictors of IVR after RNU (p = 0.019, 0.033). Kaplan-Meier survival analysis found that diagnostic ureteroscopic biopsy was a high-risk factor for IRFS (p = 0.034). Subcomponent analysis showed that pTa/Tis/T1, pT2, pT3/pT4 stage, and diagnostic ureteroscopic biopsy with pTa/Tis/T1 stage were unfavourable for IVR (p = 0.047). CONCLUSION: Diagnostic ureteroscopic biopsy before RNU should be carefully selected for patients with atypical preoperative UTUC. We believe that intravesical chemotherapy drug perfusion can be used after surgery to prevent IVR if biopsy is unavoidable, but this still requires further prospective studies.

12.
ISA Trans ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34507814

RESUMO

Bearing plays an important role in industrial equipment and it may operate under varying conditions. When the speed of shaft changes, whether monotonous or non-monotonous speed, common diagnostic approaches cannot effectively extract fault features. But encoders and tachometers are not always available. Therefore, tacholess order tracking methods which can directly extract the instantaneous rotating frequency (IRF) from vibration signal are very useful in bearing fault diagnosis under varying speed. Among these methods, the generalized linear chirplet transform (GLCT) can produce time-frequency representation without constructing any mathematical model, but there are two parameters must be set in advance. The parameters have great influence on the analysis result. To reduce the dependence on the prior knowledge of presetting the parameters in varying conditions, two different improved GLCT methods are proposed in this paper. To do with the situation where the trend of speed changes is monotonous, the scale-space is introduced to lift GLCT which can adaptively set a vital parameter, and the other parameter is set to default value. When faced with non-monotonous speed, the second method is proposed which the grey wolf optimizer (GWO) and Gini index are introduced to search the optimal parameters of GLCT without any prior knowledge. With the help of the proposed methods, the IRF can be extracted directly from vibration signal. Then, the raw signal can be resampled based on the IRF to eliminate the influences of speed. The morphological filtering is adopted to remove the noise and extract the fault characteristics order (FCO). Another two typical time-frequency analysis methods are used for comparisons. Three different signals are used for analysis to demonstrate the superiority of the proposed methods.

13.
NPJ Regen Med ; 6(1): 54, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508081

RESUMO

Finding a suitable biomaterial for scaffolding in cartilage tissue engineering has proved to be far from trivial. Nonetheless, it is clear that biomimetic approaches based on gelatin (Gel) and hyaluronic acid (HA) have particular promise. Herein, a set of formulations consisting of photo-polymerizable Gel; photo-polymerizable HA, and allogenic decellularized cartilage matrix (DCM), is synthesized and characterized. The novelty of this study lies particularly in the choice of DCM, which was harvested from an abnormal porcine with α-1,3-galactose gene knockout. The hybrid hydrogels were prepared and studied extensively, by spectroscopic methods, for their capacity to imbibe water, for their behavior under compression, and to characterize microstructure. Subsequently, the effects of the hydrogels on contacting cells (in vitro) were studied, i.e., cytotoxicity, morphology, and differentiation through monitoring the specific markers ACAN, Sox9, Coll2, and Col2α1, hypertrophy through monitoring the specific markers alkaline phosphatase (ALP) and Col 10A1. In vivo performance of the hydrogels was assessed in a rat knee cartilage defect model. The new data expand our understanding of hydrogels built of Gel and HA, since they reveal that a significant augmenting role can be played by DCM. The data strongly suggest that further experimentation in larger cartilage-defect animal models is worthwhile and has potential utility for tissue engineering and regenerative medicine.

14.
Seizure ; 92: 76-81, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34474329

RESUMO

PURPOSE: Felt stigma and social anxiety are both common in patients with epilepsy (PWE) and they share an important relationship. Here in the present study, we investigated how social anxiety and different concepts of felt stigma relate to each other in PWE in order to provide some suggestions for the prevention and intervention of social anxiety and felt stigma in PWE. METHODS: A total of 189 patients with epilepsy were enrolled in our study. Social anxiety was evaluated with the Liebowitz social anxiety scale. Felt stigma was evaluated with the Kilifi stigma scale for epilepsy. The data were subjected to network analysis. RESULTS: The findings indicated that eight edges with the strongest regularized partial correlations existed in the network, such as the edge between S3 "Embarrassed" and S4 "Disappointed", and the edge between S14 "Discriminate" and S15 "Outcast". In addition, S10 "Inferior" and S11 "Avoid" had the highest strength and predictability. The flow network of social anxiety indicated that most concepts of felt stigma were directly connected with social anxiety. The strongest edge existed between S8 "Uncomfortable" and social anxiety, while S6 "Society" and S5 "Rewarding life" were also closely connected with social anxiety. CONCLUSION: The current study highlighted the critical central concept S10 "Inferior" and critical concepts associated with social anxiety, including S8 "Uncomfortable", S6 "Society" and S5 "Rewarding life". The findings revealed in this study may offer some help in the clinical prevention and intervention of felt stigma and social anxiety in PWE. However, all of the conclusions above need further confirmatory studies to validate them.

15.
Mol Biol Evol ; 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34480565

RESUMO

All vertebrate genomes have been colonized by retroviruses along their evolutionary trajectory. While endogenous retroviruses (ERVs) can contribute important physiological functions to contemporary hosts, such benefits are attributed to long-term co-evolution of ERV and host because germline infections are rare and expansion is slow, and because the host effectively silences them. The genomes of several outbred species including mule deer (Odocoileus hemionus) are currently being colonized by ERVs, which provides an opportunity to study ERV dynamics at a time when few are fixed. We previously established the locus-specific distribution of cervid endogenous retrovirus (CrERV) in populations of mule deer. In this study we determine the molecular evolutionary processes acting on CrERV at each locus in the context of phylogenetic origin, genome location, and population prevalence. A mule deer genome was de novo assembled from short and long insert mate pair reads and CrERV sequence generated at each locus. We report that CrERV composition and diversity have recently measurably increased by horizontal acquisition of a new retrovirus lineage. This new lineage has further expanded CrERV burden and CrERV genomic diversity by activating and recombining with existing CrERV. Resulting inter-lineage recombinants then endogenize and subsequently expand. CrERV loci are significantly closer to genes than expected if integration were random and gene proximity might explain the recent expansion of one recombinant CrERV lineage. Thus, in mule deer, retroviral colonization is a dynamic period in the molecular evolution of CrERV that also provides a burst of genomic diversity to the host population.

16.
J Biomed Nanotechnol ; 17(7): 1392-1403, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34446142

RESUMO

Titanium (Ti) and its alloy implants are widely used in the field of orthopedics, and osteoporosis is an important reason for implantation failure. This study aimed to establish a quercetin (QTN) controlled release system on the surface of titanium implants and to study its effects on osteogenesis and osseointegration on the surface of implants. Polyethylenimine (PEI) was first immobilized on a titanium substrate as the base layer, and then, hyaluronic acid/chitosan-quercetin (HA/CS-QTN) multilayer films were assembled on the PEI layer by a self-assembly technique. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and contact angle measurements were used to characterize and analyze the samples. The release characteristics of QTN were studied by release assays. The osteogenic ability of the samples was evaluated by experiments on an osteoporosis rat model and MC3T3-E1 cells. The FTIR, SEM, and contact angle measurements all showed that the PEI substrate layer and HA/CS-QTN multilayer film were successfully immobilized on the titanium matrix. The drug release test showed the successful establishment of a QTN controlled release system. The in vitro results showed that osteoblasts exhibited higher adhesion, proliferation and differentiation ability on the coated titanium matrix than on the pure titanium surface. In addition, the in vivo results showed that the HA/CS-QTN coating significantly increased the new bone mass around the implant. By depositing a PEI matrix layer and HA/CS-QTN multilayer films on titanium implants, a controlled release system of QTN was established, which improved implant surface osseointegration under osteoporotic conditions. This study proposes a new implant therapy strategy for patients with osteoporosis.


Assuntos
Osteogênese , Titânio , Animais , Materiais Revestidos Biocompatíveis , Humanos , Osseointegração , Polieletrólitos , Quercetina/farmacologia , Ratos , Propriedades de Superfície
17.
Artigo em Inglês | MEDLINE | ID: mdl-34444293

RESUMO

The total amount of drug waste is expanding significantly as populations age and societies become wealthier. Drug waste is becoming a problem for health and the environment. Thus, how to reduce and effectively dispose of drug waste is increasingly becoming an issue for society. This study focuses on household drug management, which involves five sub-practices: selection, purchasing, using, storing, and disposing of drugs. A questionnaire survey was conducted in a second-tier Chinese city that reveals both problems and opportunities in these five sub-practices. The results show that consumers are aware of significant issues with regard to the safe and effective use of drugs as well as with regard to proper ways of disposing of and recycling drugs. Moreover, our analysis reveals promising opportunities for addressing these issues by developing novel services based on the idea of connecting the five involved sub-practices of household drug management. Connecting and adjusting practices in this manner can be seen as an important factor in reducing drug waste and pharmaceutical pollutants.


Assuntos
Poluição Ambiental , Preparações Farmacêuticas , China , Cidades , Poluição Ambiental/prevenção & controle , Reciclagem
18.
Oxid Med Cell Longev ; 2021: 5574130, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336102

RESUMO

Ovarian cancer (OC), the third common gynecologic malignancy, contributes to the most cancer-caused mortality in women. However, 70% of patients with OC are diagnosed at an advanced stage, of which the 5-year survival is less than 30%. Long noncoding RNAs (long ncRNAs or lncRNA), a type of RNA with exceeding 200 nucleotides in length but no protein-coding capability, have been demonstrated to involve the pathogenesis of various cancers and show considerable potential in the diagnosis of OC. In this study, we found that the LINC00909 expression in tumor and serum specimens of OC patients was elevated, determined by real-time quantitative, and droplet digital PCR. In receiver operating characteristic (ROC) analysis, our results revealed that serum LINC00909 distinguished cancers from normal ovarian tissue with 87.8% of sensitivity and 69.6% of specificity (AUC, 81.2%) and distinguished serous ovarian cancer from normal ovarian tissue with 90.0% of sensitivity and 75.9% of specificity (AUC, 84.5%). Furthermore, we observed that the tumor and serum LINC00909 level was positively associated with the International Federation of Gynecology and Obstetrics (FIGO) stage and the Eastern Cooperative Oncology Group (ECOG) score (reflecting patients' performance status). Also, patients with low serum LINC00909 level showed a longer overall (hazard ratio, HR = 1.874, p = 0.0004) and progression-free (HR = 1.656, p = 0.0017) survival. Functional assays indicated that the elevation of LINC00909 expression contributes to cell proliferation, migration, and invasion capability of ovarian cancer cells. Besides, we demonstrated that LINC00909 functions as a competing endogenous RNA (ceRNA) of MRC2 mRNA by sponging miR-23-3p, and thereby promotes epithelial-to-mesenchymal transition (EMT) of ovarian cancer cells. Therefore, we highlight that the LINC00909/miR-23b-3p/MRC2 axis is implicated in the pathogenesis of ovarian cancer, and serum LINC00909 may be a promising biomarker for the diagnosis of OC.

19.
Artigo em Inglês | MEDLINE | ID: mdl-34346229

RESUMO

Due to the excellent thermoelectric performance, bismuth telluride (Bi2Te3) compounds are highly promising for the thermoelectric conversion in the room temperature range. However, the inferior thermoelectric performance of the n-type leg severely restricts the applications of Bi2Te3-based thermoelectric couples. Herein, n-type Bi2Te2.7Se0.3 (BTS)-based thermoelectric materials incorporated with nanosized Y2O3 (0.5-3 wt %) are prepared and their thermoelectric properties are systematically studied. The dramatically improved thermoelectric performance is ascribed to the realization of a multiscale feature of Y2O3 nanoparticle (NP)-induced interfacial decorations distributed along grain boundaries, which creates massive BTS/Y2O3 interfaces for the manipulation of carrier and phonon transport properties. The geometric phase analysis is employed to further confirm the condition of local strain in the BTS composite incorporated with Y2O3 NPs. Due to the presence of heterointerfaces and high density of dislocations in BTS matrices, the minimum lattice thermal conductivity (κl) of the nanocomposites (NCs) is dramatically suppressed from 0.76 to 0.37 W m-1 K-1. With the incorporation of 3 wt % Y2O3 NPs, the Vickers hardness of the BTS/Y2O3 NC is increased by about 32%. Overall, the BTS + 1.5 wt % Y2O3 NC maintains excellent thermoelectric properties (ZTave = 1.1) in the whole operative temperature range (300-500 K). The present strategy of implementing high-density heterogeneous interfaces by Y2O3 NP addition offers an applicable pathway for fabricating high-performance thermoelectric materials with both optimized thermoelectric properties and mechanical properties.

20.
ACS Biomater Sci Eng ; 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34415138

RESUMO

The poor vascular development of an endometrium is the key cause of a thin endometrium due to the vascular endothelial growth factor (VEGF) decreasing in the glandular epithelium. Hence, inducing angiogenesis is an effective strategy for thin endometrium treatment in clinic. Herein, we developed a novel angiogenic hydrogel microsphere based on methacrylated hyaluronic acid (HAMA) loaded with VEGF for the treatment of a thin endometrium by a microfluidic electrospray technique. The generated HAMA microspheres with uniform size, porous structure, and satisfactory biocompatibility increased the drug-loading ability and controlled the drug-release rate by adjusting the hydrogel concentration. Besides, the HAMA microspheres loaded with VEGF showed satisfactory biocompatibility and promoted blood vessel formation in vitro. More importantly, the combination of HA and VEGF promoted new blood vessels and endometrial regeneration of a thin endometrium in vivo. Therefore, the combination of HA and VEGF would be conducive to the development of a drug-delivery microsphere with excellent biocompatibility and therapeutic effect for thin endometrium treatment and other biomedical applications.

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