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1.
J Am Coll Surg ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752618

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy(nCRT) for rectal cancer can lead to structural changes in collagen in the tumor microenvironment and increase the risk of postoperative anastomotic stenosis (AS). However, the quantitative relationship between AS and collagen has not been defined. This study is to quantitatively analyze the collagen features in rectal cancer and explore the relationship between the changes of collagen and postoperative anastomotic stenosis after nCRT. STUDY DESIGN: This study is a retrospective study. A total of 371 patients with rectal cancer were included. Collagen features in the resection margin of rectal cancer anastomosis was extracted by multi-photon imaging. LASSO-logistic regression was performed to select features related to AS and the collagen score (CS) was constructed. Area under the receiver operating curve (AUROC) and decision curve analysis was performed to evaluate the discrimination and clinical benefit of the nomogram. RESULTS: The probability of AS was 23% in the training cohort and 15.9% in the validation cohort. In the training cohort, the distance between tumor and resection margin, anastomotic leakage and CS were independent risk factors for postoperative AS in univariate and multivariate analyses. A nomogram was constructed based on the above results. The prediction nomogram showed good discrimination (AUROC, 0.864;95% CI, 0.776 to 0.952) and was validated in the validation cohort (AUROC, 0.918;95% CI, 0.851 to 0.985). CONCLUSIONS: CS is an independent risk factor for AS in rectal cancer after nCRT. The predictive model based on CS can predict the occurrence of postoperative AS.

2.
J Colloid Interface Sci ; 669: 477-485, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38723536

RESUMO

Solar-light photosynthesis of ammonia form N2 reduction in ultrapure water over the artificial photocatalysts is attractive but still challenging compared with Haber-Bosch process. In this work, ultrathin Fe-Ta2O5-x nanobelts were fabricated via the controllable solvothermal process for ammonia photosynthesis. The formed oxygen vacancies and Fe doping narrowed their bandgap energies and promoted the carriers' separation and transfer for Fe-Ta2O5-x nanobelts. In addition, Fe doping also resulted in the reduced working functions of the samples, indicating a weaker electron binding restriction and stronger separation and transfer of photo-induced carriers. The experimental results showed that Fe-Ta2O5-x nanobelts showed remarkably enhanced photocatalytic ammonia production performance under simulated sunlight irradiation, and the relevant ammonia production rate reached approximately 3030.86 µM g-1 h-1, which was 9.63 times of pristine Ta2O5-x and 491.0 times of commercial Ta2O5, and a relatively stable photocatalytic ammonia production performance under simulated sunlight irradiation for Fe-Ta2O5-x nanobelts. Meanwhile, it was also found that Fe doping has great influences on the photocatalytic performance under visible light and simulated sunlight irradiation, mainly because of their suitable bandgap energies and enhanced solar-light harvesting capacity. Current work indicates the great potentials of ultrathin tantalum-based functional materials for high-efficiency ammonia photosynthesis.

3.
J Org Chem ; 89(9): 6575-6583, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38656973

RESUMO

Nitroarenes are known for their stability, low toxicity, easy availability, and cost-effectiveness, making them one of the most fundamental chemical feedstocks. The direct utilization of nitroarenes as nitrogen sources in amidation reactions offers significant advantages over using arylamines. Herein, we disclose a streamlined method for constructing α-ketoamides through the direct coupling of nitroarenes with α-oxocarboxylic acids. This transformation obviates the need for preparing, isolating, and purifying arylamines, leading to improved efficiency, cost-effectiveness, and time savings.

4.
Chem Sci ; 15(10): 3552-3561, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455022

RESUMO

One of the most widely utilized methods for the construction of C(sp2)-N bonds is the transition-metal-catalyzed cross-coupling of aryl halides/boronic acids with amines, known as Ullmann condensation, Buchwald-Hartwig amination, and Chan-Lam coupling. However, aryl halides/boronic acids often require multi-step preparation while generating a large amount of corrosive and toxic waste, making the reaction less attractive. Herein, we present an unprecedented method for the C(sp2)-N formation via Buchwald-Hartwig-type reactions using synthetically upstream nitroarenes as the sole starting materials, thus eliminating the need for arylhalides and pre-formed arylamines. A diverse range of symmetrical di- and triarylamines were obtained in a single step from nitroarenes, and more importantly, various unsymmetrical di- and triarylamines were also highly selectively synthesized in a one-pot/two-step process. Furthermore, the success of the scale-up experiments, the late-stage functionalization of a drug intermediate, and the rapid preparation of hole-transporting material TCTA showcased the utility and practicality of this protocol in synthetic chemistry. Mechanistic studies indicate that this transformation may proceed via an arylamine intermediate generated in situ from the reduction of nitroarenes, which is followed by a denitrative Buchwald-Hartwig-type reaction with another nitroarene to form a C-N bond.

5.
Immun Inflamm Dis ; 12(2): e1203, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38411379

RESUMO

OBJECTIVE: Acute necrotic collection (ANC), acute peripancreatic fluid collection (APFC), pleural effusion, and ascites are common early complications of acute pancreatitis. This study aimed to investigate the relationship between 12 serum cytokines and the early complications and severity of acute pancreatitis (AP). METHODS: We retrospectively analyzed the clinical data of 307 patients with AP, and divided them into severe group and mild-to-moderate group according to the revised Atlanta classification. Propensity score matching was used to control for confounding factors. Binary logistic regression analysis was used to explore the relationship between cytokine levels and early complications of AP. RESULTS: Serum levels of interleukin (IL)-1ß, IL-5, IL-6, IL-8, IL-10, IL-17, and tumor necrosis factor-α were significantly higher in the severe acute pancreatitis (SAP) group than in the non-SAP group (p < .05). After adjusting for confounding factors, the upper quartiles of IL-6, IL-8, and IL-10 were associated with an increased risk of ANC compared with those in the lowest quartile (IL-6: quartile 3, odds ratio [OR] = 3.99, 95% confidence interval [CI] = 1.95-8.16; IL-8: quartile 4, OR = 2.47, 95% CI = 1.27-4.84; IL-10: quartile 2, OR = 2.22, 95% CI = 1.09-4.56). APFC was associated with high serum levels of IL-6 (quartile 3, OR = 1.32, 95% CI = 1.02-1.72), pleural effusions were associated with high serum levels of IL-1ß, IL-6, IL-8, and IL-10 (IL-1ß: quartile 4, OR = 2.36, 95% CI = 1.21-4.58; IL-6: quartile 3, OR = 4.67, 95% CI = 2.27-9.61; IL-8: quartile 3, OR = 2.95, 95% CI = 1.51-5.79; IL-10: quartile 4, OR = 3.20, 95% CI = 1.61-6.36), and high serum levels of IL-6 and IL-10 were associated with an increased risk of ascites (IL-6: quartile 3, OR = 3.01, 95% CI = 1.42-6.37; IL-10: quartile 3, OR = 2.57, 95% CI = 1.23-5.37). CONCLUSION: Serum cytokine levels, including IL-1ß, IL-6, IL-8, and IL-10 may be associated with the occurrence of early complications of AP. In daily clinical practice, IL-6 may be the most worthwhile cytokine to be detected.


Assuntos
Citocinas , Pancreatite , Humanos , Interleucina-10 , Doença Aguda , Ascite/etiologia , Interleucina-6 , Interleucina-8 , Estudos Retrospectivos , Pancreatite/complicações , Hospitais , Interleucina-1beta
6.
Bioeng Transl Med ; 8(6): e10586, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023722

RESUMO

Postoperative adjuvant chemotherapy (AC) for poor responders to neoadjuvant chemoradiotherapy (nCRT) remains debatable among patients with locally advanced rectal cancer (LARC), necessitating biomarkers to accurately predict the benefits of AC. This study aimed to develop a patient-derived tumor organoid (PDTO) platform to predict the benefit of AC in LARC patients showing poor nCRT response. PDTOs were established using irradiated rectal cancer specimens with poor nCRT responses, and their sensitivity to chemotherapy regimens was tested. The half-maximal inhibitory concentration (IC50) value for the PDTO drug test was defined based on the clinical outcomes, and the accuracy of the PDTO prognostic predictions was calculated. Predictive models were developed and validated using the PDTO drug test results. Between October 2018 and December 2021, 86 PDTOs were successfully constructed from 138 specimens (success rate 62.3%). The optimal IC50 cut-off value for the organoid drug test was 39.31 µmol/L, with a sensitivity of 84.75%, a specificity of 85.19%, and an accuracy of 84.88%. Multivariate Cox regression analysis revealed that the PDTO drug test was an independent predictor of prognosis. A nomogram based on the PDTO drug test was developed, showing good prognostic ability in predicting the 2-year and 3-year disease-free survivals (AUC of 0.826 [95% CI, 0.721-0.931] and 0.902 [95% CI, 0.823-0.982], respectively) and overall survivals (AUC of 0.859 [95% CI, 0.745-0.973] and 0.885 [95% CI, 0.792-0.978], respectively). The PDTO drug test can predict the benefit of postoperative AC in poor responders with LARC to nCRT.

7.
Front Psychol ; 14: 1192265, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37359872

RESUMO

Whether athletes' self-compassion predicts their emotional resilience to failure has yet to be empirically tested. Moreover, as an important physiological process of stress regulation, vagal reactivity is a plausible physiological mechanism for this relationship. Through a laboratory-based observational study of 90 college athletes, this research explores the influence of athletes' trait self-compassion on their emotional resilience when recalling failure, and examines whether vagal reactivity plays a mediating role. The results show that self-compassion did not significantly predict athletes' positive emotions but did significantly predict better recovery from negative emotions after recalling failure events. Furthermore, vagal reactivity was a significant mediator between self-compassion and recovery from negative emotions.

8.
Pharmaceutics ; 15(4)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37111673

RESUMO

Bacterial infection is a common clinical disease. Antibiotics have saved countless lives since their discovery and are a powerful weapon in the fight against bacteria. However, with the widespread use of antibiotics, the problem of drug resistance now poses a great threat to human health. In recent years, studies have investigated approaches to combat bacterial resistance. Several antimicrobial materials and drug delivery systems have emerged as promising strategies. Nano-drug delivery systems for antibiotics can reduce the resistance to antibiotics and extend the lifespan of novel antibiotics, and they allow targeting drug delivery compared to conventional antibiotics. This review highlights the mechanistic insights of using different strategies to combat drug-resistant bacteria and summarizes the recent advancements in antimicrobial materials and drug delivery systems for different carriers. Furthermore, the fundamental properties of combating antimicrobial resistance are discussed, and the current challenges and future perspectives in this field are proposed.

9.
Materials (Basel) ; 16(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36984082

RESUMO

In order to alleviate the energy crisis and propel a low-carbon economy, hydrogen (H2) plays an important role as a renewable cleaning resource. To break the hydrogen evolution reaction (HER) bottleneck, we need high-efficiency electrocatalysts. Based on the synergistic effect between bimetallic oxides, hierarchical mesoporous CoNiO2 nanosheets can be fabricated. Combining physical representations with electrochemical measurements, the resultant CoNiO2 catalysts present the hierarchical microflowers morphology assembled by mesoporous nanosheets. The ultrathin two-dimensional nanosheets and porous surface characteristics provide the vast channels for electrolyte injection, thus endowing CoNiO2 the outstanding HER performance. The excellent performance with a fewer onset potential of 94 mV, a smaller overpotential at 10 mA cm-2, a lower Tafel slope of 109 mV dec-1 and better stability after 1000 cycles makes CoNiO2 better than that of metallic Co and metallic Ni.

10.
Eur J Cancer Prev ; 32(1): 65-68, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35170548

RESUMO

Transmembrane serine proteinase 2 (TMPRSS2), which is an essential serine protease for priming spike protein of SARS-CoV-2, was found in low expression in many cancer tissue including lung cancer. However, the mechanism of severely downregulated in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) was not reported yet; the correlation between TMPRSS2 and prognosis in LUAD and LUSC is also not clear. In our present research, we found that TMPRSS2 was severely downregulated in LUAD and LUSC, and the expression of TMPRSS2 in LUAD is much lower than that of LUSC. Low TMPRSS2 expression was an independent prognostic factor for poor OS in LUAD, but not in LUSC patients. Promoter hypermethylation is one of the results of TMPRSS2 downregulated in LUAD and LUSC, whereas copy-number alteration is another reason for TMPRSS2 downregulated in LUAD but not LUSC. Then, low TMPRSS2 expression has higher prognostic value in LUAD and may be due to different immune environments and different enriched immune cells subgroups.


Assuntos
Adenocarcinoma de Pulmão , COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Prognóstico , Serina Proteases , Medicina de Precisão , SARS-CoV-2 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/prevenção & controle , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/prevenção & controle
11.
Mol Med Rep ; 27(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36367161

RESUMO

Kirsten rat sarcoma virus (KRAS) mutation is considered to be the event that leads to the initiation of pancreatic ductal adenocarcinoma (PDAC), the mutation frequency of the KRAS gene in PDAC is 90­95%. Studies have shown that wild­type KRAS (KRASWT) has a survival advantage in PDAC and can antagonize the effect of mutated KRAS G12D (KRASG12D), leading to a low cell transformation efficiency. The present study focused on the differences in biological behavior between KRASWT and KRASG12D and explored the mechanism in pancreatic cancer. Overexpressed KRASWT and KRASG12D was transfected into cells through lentiviral transfection. The differences and mechanisms were explored using cell counting kit­8 (CCK­8), clone formation, wound healing and Transwell assays, as well as western blotting, immunohistochemistry and tumor formation in nude mice. In vitro, the proliferation of KRASWT group was reduced compared with PANC­1 group, while the proliferation of KRASG12D group was not significantly changed. In vivo, the proliferation of KRASWT group was reduced and that of KRASG12D group was enhanced compared with that in the PANC­1 group. The invasion and migration of KRASWT group were decreased, while the invasion and migration of KRASG12D group were increased. Western blotting showed that the expression of E­cadherin, α­E­catenin, MMP­3, MMP­9, STAT3 and phosphorylated STAT3 in KRASWT group was increased, while no significant difference was observed in KRASG12D group. The results of immunohistochemistry were consistent with those of western blotting. KRASWT group can inhibit the proliferation of pancreatic cancer in vitro and in vivo, while KRASG12D group can significantly promote proliferation in vivo, but not significantly in vitro. Wild­type KRAS may inhibit the invasion and migration of pancreatic cancer through the Wnt/ß­catenin pathway.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma Ductal Pancreático/patologia , Vírus do Sarcoma Murino de Kirsten/metabolismo , Camundongos Nus , Mutação , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Via de Sinalização Wnt , Neoplasias Pancreáticas
12.
Int J Pharm X ; 4: 100119, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35663355

RESUMO

Rivaroxaban (RIV) is a direct Factor Xa inhibitor anticoagulant, but the oral bioavailability of RIV is estimated to be only 60% due to its poor solubility. The aim of the present study was to improve the solubility and bioavailability of RIV. Five cocrystals-p-hydroxybenzoic acid (HBA), 2,4-dihydroxybenzoic acid (DBA), nicotinamide (NA), isonicotinamide (IA), and succinic acid (SA)-were used as cofomers and were successfully obtained and characterized by powder X-ray diffraction, thermal analysis, and Fourier transform infrared spectra. RIV-DBA and RIV-HBA cocrystals showed obvious improvements in solubility, dissolution (under sink conditions), and intrinsic dissolution rates versus RIV. Moreover, the dissolution of RIV-HBA, RIV-DBA, and RIV-SA cocrystals under non-sink conditions showed obvious "spring and parachute" patterns. The in vitro permeability levels in a Caco-2 cell model of RIV-DBA and RIV-IA cocrystals were significantly improved versus RIV. Pharmacokinetic studies in beagle dogs showed that RIV-DBA and RIV-HBA cocrystals had higher bioavailability than RIV. The enhancements in solubility and bioavailability indicate the potential of RIV cocrystals as a better candidate for the treatment of thrombosis versus RIV.

13.
Gels ; 8(6)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35735708

RESUMO

In recent years, hydrogel-based research in biomedical engineering has attracted more attention. Cellulose-based hydrogels have become a research hotspot in the field of functional materials because of their outstanding characteristics such as excellent flexibility, stimulus-response, biocompatibility, and degradability. In addition, cellulose-based hydrogel materials exhibit excellent mechanical properties and designable functions through different preparation methods and structure designs, demonstrating huge development potential. In this review, we have systematically summarized sources and types of cellulose and the formation mechanism of the hydrogel. We have reviewed and discussed the recent progress in the development of cellulose-based hydrogels and introduced their applications such as ionic conduction, thermal insulation, and drug delivery. Also, we analyzed and highlighted the trends and opportunities for the further development of cellulose-based hydrogels as emerging materials in the future.

14.
Clin Interv Aging ; 17: 615-626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35502188

RESUMO

Background: Inflammation is closely associated with prognosis in patients with aneurysmal subarachnoid hemorrhage (aSAH), which is orchestrated by inflammatory cytokines. Therefore, this study aimed to investigate the levels of inflammatory cytokines in the early stage of aSAH and their predictive value for prognosis. Methods: In this retrospective study, 206 patients with aSAH were recruited and assigned to a severe group (WFNS grade ≥ 4) and a mild group (WFNS grade < 4) according to the severity of patients on admission. Flow cytometry was performed to detect the levels of 12 inflammatory cytokines in the serum of patients. Then, patients were grouped into a poor prognosis group (mRS score ≥ 4) and a good prognosis group (mRS score < 4) based on their prognosis after 3 months of discharge to compare the relationship between cytokines and prognosis. Propensity score matching (PSM) was utilized to control confounding factors. The correlation between inflammatory factors and prognosis was determined using Spearman correlation, and the predictive efficacy of inflammatory factors was tested by a receiver operating characteristic curve. Results: Serum IL-1ß, IL-5, IL-6, IL-8, IL-10, IFN-γ, and TNF-α levels were significantly higher in the mild group than in the severe group and in the poor prognosis group than in the good prognosis group. After PSM, the differences in IL-1ß, IL-5, IFN-α, and IFN-γ levels disappeared between the two groups, whereas IL-2, IL-6, IL-8, IL-10, and TNF-α levels remained higher in the poor prognosis group than in the good prognosis group. Additionally, IL-2, IL-6, IL-8, and IL-10 levels were positively correlated with mRS scores. Moreover, the predictive value was found to be the highest for IL-6 and the lowest for TNF-α. Conclusion: Inflammation degree was related to the severity of aSAH. Inflammatory markers, including IL-6, IL-10, IL-8, IL-2, and TNF-α, might predict the poor prognosis of aSAH.


Assuntos
Hemorragia Subaracnóidea , Citocinas , Humanos , Inflamação/complicações , Interleucina-10 , Interleucina-2 , Interleucina-5 , Interleucina-6 , Interleucina-8 , Estudos Retrospectivos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/diagnóstico , Fator de Necrose Tumoral alfa
15.
J Oncol ; 2022: 3379027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295710

RESUMO

F11R receptor (F11R/junctional adhesion molecule-A/F11R-A) is preferentially concentrated at tight junctions and influences epithelial cell morphology and migration. Numerous studies have shown that the aberrant expression of F11R contributes to tumor progression including pancreatic cancer. However, the significance of F11R in various tumors is controversial, and the role of F11R in regulating the malignant behaviors of human pancreatic cancer is unknown. To investigate the role of F11R in the carcinogenesis of pancreatic cancer and the potential targets of F11R as a therapeutic target for pancreatic cancer, we knocked down F11R in the pancreatic cancer cell line PANC-1 using lentiviral approaches. We found that F11R silencing led to decreased cell proliferation, a loss of cell invasiveness, cell cycle arrest in the G1 phase, and enhanced cell apoptosis. The present results suggest that F11R may be a promising therapeutic target for pancreatic cancer.

16.
Comput Math Methods Med ; 2022: 9995962, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35075371

RESUMO

BACKGROUND: This study is aimed at evaluating the diagnostic efficacy of ultrasound-based risk stratification for thyroid nodules in the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and the American Thyroid Association (ATA) risk stratification systems. METHODS: 286 patients with thyroid cancer were included in the tumor group, with 259 nontumor cases included in the nontumor group. The ACR TI-RADS and ATA risk stratification systems assessed all thyroid nodules for malignant risks. The diagnostic effect of ACR and ATA risk stratification system for thyroid nodules was evaluated by receiver operating characteristic (ROC) analysis using postoperative pathological diagnosis as the gold standard. RESULTS: The distributions and mean scores of ACR and ATA rating risk stratification were significantly different between the tumor and nontumor groups. The lesion diameter > 1 cm subgroup had higher malignant ultrasound feature rates detected and ACR and ATA scores. A significant difference was not found in the ACR and ATA scores between patients with or without Hashimoto's disease. The area under the receiver operating curve (AUC) for the ACR TI-RADS and the ATA systems was 0.891 and 0.896, respectively. The ACR had better specificity (0.90) while the ATA system had higher sensitivity (0.92), with both scenarios having almost the same overall diagnostic accuracy (0.84). CONCLUSION: Both the ACR TI-RADS and the ATA risk stratification systems provide a clinically feasible thyroid malignant risk classification, with high thyroid nodule malignant risk diagnostic efficacy.


Assuntos
Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Adulto , Idoso , Biologia Computacional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco , Sociedades Médicas , Neoplasias da Glândula Tireoide/classificação , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/classificação , Nódulo da Glândula Tireoide/diagnóstico , Ultrassonografia/estatística & dados numéricos , Estados Unidos
17.
Nanomaterials (Basel) ; 11(3)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33808024

RESUMO

In this paper, the optimizations of vertically-stacked horizontal gate-all-around (GAA) Si nanosheet (NS) transistors on bulk Si substrate are systemically investigated. The release process of NS channels was firstly optimized to achieve uniform device structures. An over 100:1 selective wet-etch ratio of GeSi to Si layer was achieved for GeSi/Si stacks samples with different GeSi thickness (5 nm, 10 nm, and 20 nm) or annealing temperatures (≤900 °C). Furthermore, the influence of ground-plane (GP) doping in Si sub-fin region to improve electrical characteristics of devices was carefully investigated by experiment and simulations. The subthreshold characteristics of n-type devices were greatly improved with the increase of GP doping doses. However, the p-type devices initially were improved and then deteriorated with the increase of GP doping doses, and they demonstrated the best electrical characteristics with the GP doping concentrations of about 1 × 1018 cm-3, which was also confirmed by technical computer aided design (TCAD) simulation results. Finally, 4 stacked GAA Si NS channels with 6 nm in thickness and 30 nm in width were firstly fabricated on bulk substrate, and the performance of the stacked GAA Si NS devices achieved a larger ION/IOFF ratio (3.15 × 105) and smaller values of Subthreshold swings (SSs) (71.2 (N)/78.7 (P) mV/dec) and drain-induced barrier lowering (DIBLs) (9 (N)/22 (P) mV/V) by the optimization of suppression of parasitic channels and device's structure.

18.
Dalton Trans ; 50(11): 3867-3873, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33666605

RESUMO

Vanadium-based oxides with relatively high theoretical capacity have been regarded as promising electrode materials for boosting energy conversion and storage. However, their poor electrical conductivity usually leads to unsatisfied performance and poor cycling stability. Herein, uniform V2O3/N-doped carbon hollow nanospheres (V2O3/NC HSs) with mesoporous structures were successfully synthesized through a melamine-assisted simple hydrothermal reaction and carbonization treatment. We demonstrated that the introduction of melamine played an essential role in the construction of V2O3/NC HSs. Benefitting from the special mesoporous structure and large specific surface area, the as-obtained sample exhibited enhanced conductivity and structural stability. As a proof of concept, well-defined V2O3/NC HSs exhibited excellent cycling stability and rate performance for sodium-ion batteries, and achieved a discharge capacity of 263.8 mA h g-1 at a current density of 1.0 A g-1 after 1000 cycles, one of the best performances of V-based compounds. The enhanced performance could be attributed to the synergistic effect of the hollow structure and surface carbon coating. The present work describes the design of the morphology and structure of vanadium-based oxides for energy storage devices.

19.
Nanomaterials (Basel) ; 11(2)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530292

RESUMO

A 16-nm-Lg p-type Gate-all-around (GAA) silicon nanowire (Si NW) metal oxide semiconductor field effect transistor (MOSFET) was fabricated based on the mainstream bulk fin field-effect transistor (FinFET) technology. The temperature dependence of electrical characteristics for normal MOSFET as well as the quantum transport at cryogenic has been investigated systematically. We demonstrate a good gate-control ability and body effect immunity at cryogenic for the GAA Si NW MOSFETs and observe the transport of two-fold degenerate hole sub-bands in the nanowire (110) channel direction sub-band structure experimentally. In addition, the pronounced ballistic transport characteristics were demonstrated in the GAA Si NW MOSFET. Due to the existence of spacers for the typical MOSFET, the quantum interference was also successfully achieved at lower bias.

20.
Drug Des Devel Ther ; 14: 4703-4715, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173280

RESUMO

PURPOSE: The physiologic transition from a fetus to a neonate is composed of a series of complex processes that include changes in cerebral tissue oxygenation saturation (cSO2). Monitoring this process is of great importance. This study aimed to define the cSO2 reference interval in neonates without medical support, extending the measurements until 1 hour after birth, and to determine the incidence of abnormally low or high regional cerebral oxygenation during the neonatal transition. PATIENTS AND METHODS: A total of 418 neonates delivered by cesarean section were enrolled. Near-infrared spectroscopy was used to monitor cerebral oxygenation. RESULTS: We found that cSO2 of the non-oxygen-inhaled intrathecal anesthesia in neonates without medical support increased from about 49.0% in the second minute. Most of them reached cSO2 relative stabilization at 55.7-81.0% between 7 and 8 minutes after birth. One hour after birth, newborn cSO2 was maintained at 78.0-87.0%. The low cSO2 rate among babies born under intrathecal anesthesia with and without maternal oxygen inhalation during cesarean sections was approximately 4.5% and 9.0%, respectively. CONCLUSION: We reported the trend in cSO2 from 2 minutes after birth to 1 hour in the neonatal nursing room and determined the incidence of abnormal regional cSO2 during this neonatal transition period. Anesthesiologists should pay special attention to the risk of cSO2 abnormalities in newborns when managing pregnant women with comorbidities.


Assuntos
Circulação Cerebrovascular , Oxigênio/metabolismo , Adulto , Cesárea , Feminino , Humanos , Recém-Nascido , Monitorização Fisiológica , Gravidez , Estudos Prospectivos
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