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1.
Microsc Microanal ; 29(3): 1190-1204, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37749671

RESUMO

Acupuncture can ameliorate or treat diseases according to the meridian theory in traditional Chinese medicine (TCM); however, its mechanism has not been scientifically clarified. On the other hand, telocytes (TCs) are morphologically in accordance with the meridian system, which needs further cytological investigations and acupuncture confirmation. The present study showed that acupuncture could activate TCs in several ways, alleviating rabbit ulcerative colitis. TCs could cytologically communicate the acupoints, the acupuncture sites in skin with their corresponding large intestine by TC homo-cellular junctions, exosomes around TCs, and TC-mediated nerves or blood vessels. TCs expressed transient receptor potential vanilloid type 4, the mechanosensitive channel protein that can transduce the mechanical stimulation of acupuncture into biochemical signals transferring along the extremely thin and long TCs. Collectively, a cellular mechanism diagram of acupuncture was concluded based on TC characteristics. Those results also confirmed the viewpoint that TCs were the key cells of meridian essence in TCM.


Assuntos
Terapia por Acupuntura , Colite Ulcerativa , Meridianos , Telócitos , Animais , Coelhos , Colite Ulcerativa/terapia , Comunicação
2.
Angew Chem Int Ed Engl ; 62(22): e202301507, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37005226

RESUMO

Electrochemical reduction reaction of carbon monoxide (CORR) offers a promising way to manufacture acetic acid directly from gaseous CO and water at mild condition. Herein, we discovered that the graphitic carbon nitride (g-C3 N4 ) supported Cu nanoparticles (Cu-CN) with the appropriate size showed a high acetate faradaic efficiency of 62.8 % with a partial current density of 188 mA cm-2 in CORR. In situ experimental and density functional theory calculation studies revealed that the Cu/C3 N4 interface and metallic Cu surface synergistically promoted CORR into acetic acid. The generation of pivotal intermediate -*CHO is advantage around the Cu/C3 N4 interface and migrated *CHO facilitates acetic acid generation on metallic Cu surface with promoted *CHO coverage. Moreover, continuous production of acetic acid aqueous solution was achieved in a porous solid electrolyte reactor, indicating the great potential of Cu-CN catalyst in the industrial application.

3.
J Am Chem Soc ; 144(4): 1556-1571, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35060721

RESUMO

Cyclohexanone and benzoquinone are important chemicals in chemical and manufacturing industries. The simultaneous production of cyclohexanone and benzoquinone by the reaction of phenol and water is an ideal route for the economical production of the two chemicals. In principle, this can be achieved in an electrochemical reaction system that couples the cathodic reduction of phenol to cyclohexanone and the anodic oxidation of phenol to benzoquinone, which has not been realized. Here, we report the first work on this integration strategy, where nitrogen-doped hierarchically porous carbon (NHPC)-supported NiPt and FeRu designed in this work are very efficient and selective cathode and anode catalysts, affording >99.9% selectivities to both cyclohexanone and benzoquinone. The excellent electrocatalytic performance of the catalysts can be ascribed to the poor absorption capability of the NiPt alloy nanoparticles (NPs) for cyclohexanone and Fe single-atom decorated Ru NPs for benzoquinone, which avoids the excessive reduction and oxidation of the desired products. The reaction pathway is proposed on the basis of control experiments, in which two phenol molecules react with one H2O molecule with 100% atom-efficiency. In the scale-up experiment at the 1 g scale, NiPt/NHPC and FeRu/NHPC exhibit excellent durability and stability, which enables this integrated system to afford 645.3 mg of cyclohexanone and 691.7 mg of benzoquinone synchronously in an operating time of 90 h.

4.
J Am Chem Soc ; 144(32): 14769-14777, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35924845

RESUMO

Non-copper electrocatalysts are seldom reported to generate C2+ products, and the efficiency over these catalysts is low. In this work, we report a nitrogen-doped γ-Fe2O3 (xFe2O3-N@CN) electrocatalyst, which yield C2H6 as the major product in an H-cell. At -2.0 V vs Ag/Ag+, the Faradaic efficiency (FE) for ethane reaches 42% with a current density of 32 mA cm-2. This is the first report about selective CO2 reduction to ethane (C2H6) over an iron-based catalyst. The results showed that the catalyst possessing FeO1.5-nNn sites enriched with oxygen vacancies was beneficial for the stabilization of *COOH intermediates. The exposure of two adjacent surfaces of Fe atoms was conducive to lowering the energy barrier for C-C coupling over FeO1.5-nNn sites, facilitating the generation of C2H6. This work provides a strategy for the design of a novel iron-based catalyst with tunable local coordination and electronic structures for converting CO2 into C2 products in the CO2RR.

5.
Virol J ; 19(1): 201, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36447230

RESUMO

BACKGROUND: Classical swine fever (CSF), African swine fever (ASF), and atypical porcine pestivirus (APPV) are acute, virulent, and contagious viral diseases currently hampering the pig industry in China, which result in mummification or stillbirths in piglets and mortality in pigs. Diagnostic assays for the differentiation of infection and vaccination of CSFV, in addition to the detection of ASFV and APPV, are urgently required for better prevention, control, and elimination of these viral diseases in China. METHODS: A quadruple PCR-based gene microarray assay was developed in this study to simultaneously detect wild-type and vaccine CSFV strains, ASFV and APPV according to their conserved regions. Forty-two laboratory-confirmed samples, including positive samples of 10 other swine viral diseases, were tested using this assay to confirm its high specificity. RESULTS: This assay's limit of detections (LODs) for the wild-type and vaccine CSFV were 6.98 and 6.92 copies/µL. LODs for ASFV and APPV were 2.56 × 10 and 1.80 × 10 copies/µL, respectively. When compared with standard RT-PCR or qPCR for CSFV (GB/T 26875-2018), ASFV (MARR issue No.172), or APPV (CN108611442A) using 219 clinical samples, the coincidence was 100%. The results showed that this assay with high sensitivity could specifically distinguish ASFV, APPV, and CSFV, including CSFV infection and immunization. CONCLUSION: This assay provides a practical, simple, economic, and reliable test for the rapid detection and accurate diagnosis of the three viruses and may have good prospects for application in an epidemiological investigation, prevention, and control and elimination of these three diseases.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Febre Suína Clássica , Pestivirus , Doenças dos Suínos , Vacinas , Animais , Suínos , Vírus da Febre Suína Clássica/genética , Pestivirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/prevenção & controle
6.
Angew Chem Int Ed Engl ; 60(40): 21979-21987, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34346160

RESUMO

Using renewable electricity to drive CO2 electroreduction is an attractive way to achieve carbon-neutral energy cycle and produce value-added chemicals and fuels. As an important platform molecule and clean fuel, methanol requires 6-electron transfer in the process of CO2 reduction. Currently, CO2 electroreduction to methanol suffers from poor efficiency and low selectivity. Herein, we report the first work to design atomically dispersed Sn site anchored on defective CuO catalysts for CO2 electroreduction to methanol. It exhibits high methanol Faradaic efficiency (FE) of 88.6 % with a current density of 67.0 mA cm-2 and remarkable stability in a H-cell, which is the highest FE(methanol) with such high current density compared with the results reported to date. The atomic Sn site, adjacent oxygen vacancy and CuO support cooperate very well, leading to higher double-layer capacitance, larger CO2 adsorption capacity and lower interfacial charge transfer resistance. Operando experiments and density functional theory calculations demonstrate that the catalyst is beneficial for CO2 activation via decreasing the energy barrier of *COOH dissociation to form *CO. The obtained key intermediate *CO is then bound to the Cu species for further reduction, leading to high selectivity toward methanol.

7.
Fish Shellfish Immunol ; 97: 173-181, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31857223

RESUMO

It is conceivable that pathological conditions can cause intestinal barrier disruption and innate immune dysfunction. However, very limited information has been reported on the effect of seasonal variance on intestinal barriers and innate immunity. The present study was designed to investigate the seasonal variance in intestinal epithelial barriers and the associated innate immune response of turtle intestines during hibernation and nonhibernation periods. Goblet cells (GCs) demonstrated dynamic actions of the mucosal barrier with strong Muc2 protein expression during hibernation. However, weak Muc2 expression during nonhibernation was confirmed by immunohistochemistry, immunofluorescence and immunoblotting. Furthermore, light and transmission electron microscopy revealed that the hypertrophy of GCs resulted in the hypersecretion of mucus granules (MGs) and created a well-developed mucosal layer during hibernation. The absorptive cells (ACs), forming a physical barrier of tight junctions, and desmosomes were firmly anchored during hibernation. Conversely, during nonhibernation, the integrity of tight junctions, adherence junctions and desmosomes was noticeable expanded, causing increased paracellular permeability. As further confirmation, there was strong zonula occluden-1 (ZO-1) and connexins 43 (Cx43) protein expression during hibernation and weak ZO-1 and Cx43 expression during nonhibernation. Moreover, the expression level of the innate immune response proteins Toll-like receptors 2 and 4 (TLR2 and 4) were enhanced during hibernation and were reduced during nonhibernation. These results provide rich information about the seasonal fluctuations that interrupt intestinal epithelial barriers and innate immune response, which might be essential for protection and intestinal homeostasis.


Assuntos
Imunidade Inata , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Estações do Ano , Tartarugas/imunologia , Tartarugas/fisiologia , Animais , Células Epiteliais/imunologia , Células Caliciformes/imunologia , Hibernação , Hipertrofia , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Mucina-2/genética , Junções Íntimas/metabolismo
8.
Phys Chem Chem Phys ; 20(16): 11386-11395, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29645034

RESUMO

The characters of σ- and π-holes of bromopentafluorobenzene (C6F5Br) enable it to interact with an electron-rich atom or group like pyridine which possesses an electron lone-pair N atom and a π ring. Theoretical studies of intermolecular interactions between C6F5Br and C5H5N have been carried out at the M06-2X/aug-cc-pVDZ level without and with the counterpoise method, together with single point calculations at M06-2X/TZVP, wB97-XD/aug-cc-pVDZ and CCSD(T)/aug-cc-pVDZ levels. The σ- and π-holes of C6F5Br exhibiting positive electrostatic potentials make these sites favorably interact with the N atom and the π ring of C5H5N with negative electrostatic potentials, leading to five different dimers connected by a σ-holen bond, a σ-holeπ bond or a π-holeπ bond. Their geometrical structures, characteristics, nature and spectroscopy behaviors were systematically investigated. EDA analyses reveal that the driving forces in these dimers are different. NCI, QTAIM and NBO analyses confirm the existence of intermolecular interactions formed via σ- and π-holes of C6F5Br and the N atom and the π ring of C5H5N. The experimental IR and Raman spectra gave us important information about the formation of molecular complexes between C6F5Br and C5H5N. We expect that the results could provide valuable insights into the investigation of intermolecular interactions involving σ- and π-holes.

9.
Nano Lett ; 17(10): 6117-6124, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28857573

RESUMO

Light-weight magnesium alloys with high strength are especially desirable for the applications in transportation, aerospace, electronic components, and implants owing to their high stiffness, abundant raw materials, and environmental friendliness. Unfortunately, conventional strengthening methods mainly involve the formation of internal defects, in which particles and grain boundaries prohibit dislocation motion as well as compromise ductility invariably. Herein, we report a novel strategy for simultaneously achieving high specific yield strength (∼160 kN m kg-1) and good elongation (∼23.6%) in a duplex magnesium alloy containing 8 wt % lithium at room temperature, based on the introduction of densely hierarchical {101̅1}-{101̅1} double contraction nanotwins (DCTWs) and full-coherent hexagonal close-packed (hcp) particles in twin boundaries by ultrahigh pressure technique. These hierarchical nanoscaled DCTWs with stable interface characteristics not only bestow a large fraction of twin interface but also form interlaced continuous grids, hindering possible dislocation motions. Meanwhile, orderly aggregated particles offer supplemental pinning effect for overcoming latent softening roles of twin interface movement and detwinning process. The processes lead to a concomitant but unusual situation where double contraction twinning strengthens rather than weakens magnesium alloys. Those cutting-edge results provide underlying insights toward designing alternative and more innovative hcp-type structural materials with superior mechanical properties.

10.
Compr Psychiatry ; 55(7): 1688-95, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25060989

RESUMO

BACKGROUND: Although no more traumatic stimuli exists, a variety of symptoms are persisting in chronic Posttraumatic Stress Disorder (PTSD) patients. It is therefore necessary to explore the spontaneous brain activity of treatment-naïve PTSD patients during resting-state. METHOD: Seventeen treatment-naïve PTSD patients and twenty traumatized controls were recruited and underwent a resting functional magnetic resonance imaging (Rs-fMRI) scan. The differences of regional brain spontaneous activity between the participants with and without PTSD were measured by Amplitude of Low-frequency fluctuation (ALFF). The relationship between the altered brain measurements and the symptoms of PTSD were analyzed. RESULT: Compared to traumatized controls, the PTSD group showed significantly altered ALFF in many emotion-related brain regions, such as the medial anterior cingulate cortex (MACC), dorsolateral prefrontal cortex (DLPFC), insular (IC), middle temporal gyrus (MTG), and ventral posterior cingulate cortex (VPCC). Interestingly this is the first report of a hyperactive visual cortex (V1/V2) during resting-state in treatment-naïve PTSD patients. There were significant positive correlations between ALFF values in the bilateral visual cortex and re-experiencing or avoidance in PTSD. Negative correlation was observed between ALFF values in MACC and avoidance. CONCLUSION: This study suggested that the visual cortex and the MACC may be involved in the characteristic symptoms of chronic PTSD, such as re-experiencing and avoidance. Future studies that focus on these areas of the brain are required, as alteration of these areas may act as a biomarker and could be targeted in future treatments for PTSD.


Assuntos
Giro do Cíngulo/fisiopatologia , Neurônios/fisiologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Córtex Visual/fisiopatologia , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Descanso , Adulto Jovem
11.
Fundam Res ; 3(3): 430-433, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-38933763

RESUMO

The bcc-structured Mg-Li alloy is currently the engineering metallic material with the lowest density, but it has not been widely used due to its low strength. In this paper, alloying Zn effectively improves the strength of the bcc-structured Mg-Li alloy. Due to the semi-coherent B2 structured nanoparticles, the compressive yield strength of the as-cast Mg-13Li-9Zn alloy reaches higher than 300 MPa. Due to the solid solution strengthening of Zn and the spinodal zone, the compressive yield strength of the as-quenched Mg-13Li-15Zn (LZ1315) alloy immediately increases to 400 MPa. In addition, the as-quenched LZ1315 alloy exhibits natural aging strengthening behavior. Due to the precipitation of B2 nanoparticles, the yield strength of the peak aged alloy is up to 495 MPa.

12.
Nanomaterials (Basel) ; 13(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37049312

RESUMO

A high-performance Mg-10Gd-4Dy-1.5Ag-1Zn-0.5Zr (wt.%, EQ142X) alloy was designed by multi-element composite addition in this work, obtaining a high yield strength (~396 MPa) and ultimate tensile strength (~451 MPa) after hot extrusion and ageing. The high strength is mainly related to fine grains and nano-precipitates, especially the latter. ß' and γ″ nano-precipitation with high fractions are the main strengthening phases, leading to a strengthening increment of ~277 MPa. Moreover, the multi-element alloying in this study promotes the basal-prismatic network strengthening structure, composed of ß' nano-precipitation with (1-210) habit planes, γ″ nano-precipitation with (0001) habit planes, basal plane stacking faults and 14H-long period stacking ordered phase. In addition, the dislocations and fine grains introduced by the hot-extrusion process not only accelerate the precipitation rate of nanostructure and thus improve the ageing hardening efficiency, but also facilitate the formation of more uniform and finer nano-precipitation. Thus, it is proposed that introducing nano-precipitates network into fine-grained structure is an effective strategy for developing high-strength Mg alloys.

13.
Front Microbiol ; 14: 1147652, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970668

RESUMO

Foot-and-mouth disease (FMD) is highly contagious and affects the economy of many countries worldwide. Serotype O is the most prevalent and is present in many regions of Asia. Lineages O/SEA/Mya-98, O/Middle East-South Asia (ME-SA)/PanAsia, O/Cathay and O/ME-SA/Ind-2001 have been circulating in Asian countries. Low antigenic matching between O/Cathay strains and current vaccine strains makes the disease difficult to control, therefore, analyzing the molecular evolution, diversity, and host tropisms of FMDV Serotype O in Asia may be helpful. Our results indicate that Cathay, ME-SA, and SEA are the predominant topotypes of FMDV serotype O circulating in Asia in recent years. Cathay topotype FMDV evolves at a higher rate compared with ME-SA and SEA topotypes. From 2011 onwards, the genetic diversity of the Cathay topotype has increased substantially, while large reductions were found in the genetic diversity of both ME-SA and SEA topotypes, suggesting a trend that infections sustained by the Cathay topotype were becoming a more severe epidemic in recent years. Analyzing the distributions of host species through time in the dataset, we found that the O/Cathay topotype was characterized by a highly swine-adapted tropism in contrast with a distinct host preference for O/ME-SA. The O/SEA topotype strains identified in Asia were isolated mainly from cattle until 2010. It is worth noting that there may be a fine-tuned tropism of the SEA topotype viruses for host species. To further explore the potential molecular mechanism of host tropism divergence, we analyzed the distribution of structure variations on the whole genome. Our findings suggest that deletions in the PK region may reflect a common pattern of altering the host range of serotype O FMDVs. In addition, the divergence of host tropism may be due to accumulated structural variations across the viral genome, rather than a single indel mutation.

14.
Materials (Basel) ; 16(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37110067

RESUMO

Magnesium-lithium alloys are popular in the lightweight application industry for their very low density. However, as the lithium content increases, the strength of the alloy is sacrificed. Improving the strength of ß-phase Mg-Li alloys is urgently needed. The as-rolled Mg-16Li-4Zn-1Er alloy was multidirectionally rolled at various temperatures in comparison to conventional rolling. The results of the finite element simulations showed that multidirectional rolling, as opposed to conventional rolling, resulted in the alloy effectively absorbing the input stress, leading to reasonable management of stress distribution and metal flow. As a result, the alloy's mechanical qualities were improved. By modifying the dynamic recrystallization and dislocation movement, both high-temperature (200 °C) and low-temperature (-196 °C) rolling greatly increased the strength of the alloy. During the multidirectional rolling process at -196 °C, a large number of nanograins with a diameter of 56 nm were produced and a strength of 331 MPa was obtained.

15.
Materials (Basel) ; 16(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37109840

RESUMO

The effects of solid solution treatment duration on the corrosion behavior and microstructure behavior of the cast Mg-8.5Li-6.5Zn-1.2Y (wt.%) alloy were investigated. This study revealed that with the treatment time for solid solutions increasing from 2 h to 6 h, the amount of α-Mg phase gradually decreases, and the alloy presents a needle-like shape after solid solution treatment for 6 h. Meanwhile, when the solid solution treatment time increases, the I-phase content drops. Exceptionally, under 4 h of solid solution treatment, the I-phase content has increased, and it is dispersed uniformly over the matrix. What we found in our hydrogen evolution experiments is that the hydrogen evolution rate of the as-cast Mg-8.5Li-6.5Zn-1.2Y alloy following solid solution processing for 4 h is 14.31 mL·cm-2·h-1, which is the highest rate. In the electrochemical measurement, the corrosion current density (icorr) value of as-cast Mg-8.5Li-6.5Zn-1.2Y alloy following solid solution processing for 4 h is 1.98 × 10-5, which is the lowest density. These results indicate that solid solution treatment can significantly improve the corrosion resistance of the Mg-8.5Li-6.5Zn-1.2Y alloy. The I-phase and the α-Mg phase are the primary elements influencing the corrosion resistance of the Mg-8.5Li-6.5Zn-1.2Y alloy. The existence of the I-phase and the border dividing the α-Mg phase and ß-Li phase easily form galvanic corrosion. Although the I-phase and the boundary between the α-Mg phase and ß-Li phase will be corrosion breeding sites, they are more effective in inhibiting corrosion.

16.
Front Surg ; 9: 984043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338633

RESUMO

Objective: To investigate the clinical efficacy of the subxiphoid approach for early anterior mediastinal thymoma and evaluate its advantages over the lateral intercostal approach. Methods: A total of 345 patients with early anterior mediastinal thymoma were retrospectively analyzed from January 2016 to December 2020 in the First Affiliated Hospital of Soochow University. Out of these, 99 patients underwent subxiphoid video-assisted thoracoscopic thymectomy and 246 patients underwent transthoracic video-assisted thoracoscopic thymectomy. We compared the intraoperative conditions (such as operation time and intraoperative blood loss), postoperative conditions [such as postoperative pleural drainage volume, extubation time, postoperative hospital stay, and postoperative visual analogue scale (VAS) pain score], and postoperative complications (such as death, pneumonia, delayed wound healing, cardiac arrhythmia, and phrenic nerve injury) of the two groups and analyzed the clinical advantages of the subxiphoid approach for treating early anterior mediastinal thymoma. Results: There was no significant difference between the two groups in terms of general clinical features, operation time, and postoperative complications (P > 0.05).However, there was a significant difference in terms of intraoperative blood loss, postoperative pleural drainage volume, tube extubation time, postoperative hospital stay, postoperative VAS pain score, and postoperative analgesics (a significantly decreased flurbiprofen axetil amount) (P < 0.05). Conclusion: Compared with the lateral intercostal thoracic approach, the subxiphoid approach had advantages in terms of intraoperative blood loss, postoperative hospital stay, tube extubation time, postoperative pleural drainage volume, postoperative VAS pain score, and analgesics dosage. It could provide a better view of the bilateral pleural cavities and more thorough thymectomy and superior cosmesis, and it proved to be a safe and feasible minimally invasive surgical method.

17.
Ann Transl Med ; 10(18): 988, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36267730

RESUMO

Background: Primary mediastinal germ cell tumors (PMGCT) represent a rare but sometimes highly aggressive type of mediastinal tumors. The current prognostic models for PMGCT are insufficient. This study was undertaken to establish and validate an individualized nomogram for predicting the overall survival (OS) of patients with PMGCT. Methods: We conducted a retrospective analysis of patients with PMGCT diagnosed between 2000 and 2018 in the Surveillance, Epidemiology, and End Results (SEER) database in the United States. Clinical variables included surgery subtype, gender, treatment regimens, age, histology, tumor size, stage, chemotherapy, radiation, race, and survival-related information. The main outcome measure was survival duration. The Kaplan-Meier method along with the log-rank test were utilized to estimate the OS. Independent prognostic factors were identified by performing the univariate and multivariate Cox proportional hazards regression analyses, from which an individualized nomogram was constructed to predict 3-, 5-, and 10-year OS of patients with PMGCT. The concordance index (C-index) and calibration curve were used to verify the discrimination and accuracy of the nomogram. Results: A total of 845 patients with PMGCT were recruited from the SEER database and further randomly assigned to a training set (n=635) and a validation set (n=210) at a ratio of 7:3. The 3-, 5-, and 10-year OS for overall PMGCT was 70.0%, 67.1%, and 63.9%, respectively. Cox regression analysis indicated that age, tumor size, stage, chemotherapy, radiation, histology, and surgery type were as independent factors for OS in patients with PMGCT (P<0.05). An individualized nomogram for OS was constructed utilizing these variables, with the C-index of 0.714 [95% confidence interval (CI): 0.695 to 0.743] and 0.756 (95% CI: 0.735 to 0.787) in the training and validation groups. Moreover, good levels of agreement were observed according to the calibration curve between the predicted and actual 3-, 5-, and 10-year survival rates both in the training and validated cohorts, showing that the model could accurately predict patient prognosis. Conclusions: This study documented the first attempt at establishing and validating a novel nomogram for predicting the 3-, 5-, and 10-year OS probabilities of PMGCT. The prognostic nomogram was demonstrated to have good performance for predicting individualized OS of patients with PMGCT.

18.
Materials (Basel) ; 15(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36295179

RESUMO

The effects of laser welding parameters on the interface microstructure of AZ31B magnesium alloy and 304 stainless steel were investigated. After welding, a scanning electron microscope and ultra-depth of field microscope were used to observe the microstructure of the welded material, to analyze the effects of power on the interface morphology. The simulation of laser welding of magnesium and steel was carried out by the COMSOL software. The results showed that when the power was 15 W-20 W, the temperature did not reach the melting point of magnesium alloy, there was MgO at the welding, and the interface had poor connection strength. When the power was 35 W-50 W, the temperature reached or even exceeded the boiling point of magnesium alloy, and the interface formed hot cracks, pores, and oxides and had poor joint strength. When the power was 25 W-30 W, the temperature was between the melting point and boiling point of magnesium, and the interface had excellent connection strength.

19.
Chem Sci ; 13(28): 8388-8394, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35919725

RESUMO

The electroreduction of CO2 to CH4 has attracted extensive attention. However, it is still a challenge to achieve high current density and faradaic efficiency (FE) for producing CH4 because the reaction involves eight electrons and four protons. In this work, we designed Cu nanoparticles supported on N-doped carbon (Cu-np/NC). It was found that the catalyst exhibited outstanding performance for the electroreduction of CO2 to CH4. The FE toward CH4 could be as high as 73.4% with a high current density of 320 mA cm-2. In addition, the mass activity could reach up to 6.4 A mgCu -1. Both experimental and theoretical calculations illustrated that the pyrrolic N in NC could accelerate the hydrogenation of *CO to the *CHO intermediate, resulting in high current density and excellent selectivity for CH4. This work conducted the first exploration of the effect of N-doped species in composites on the electrocatalytic performance of CO2 reduction.

20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(3): 397-400, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21827007

RESUMO

OBJECTIVE: To explore the pathogenesis of posttraumatic stress disorder (PTSD) by studying default mode network during the resting state in patients with PTSD after homologous traumatic experience. METHODS: Seventeen PTSD patients and 20 matched normal controls received the examnation of resting-state fMRI scanning. Left and right posterior cingulate cortex was regarded as seed region respectively, and the functional connectivity about whole brain was assessed by using resting-state functional connectivity analysis. RESULTS: Compared with control group, the patients with PTSD showed that the brain area with decreased functional connectivity included left superior frontal gyrus and right fusiform gyrus, while the brain area with increased functional connectivity included right precuneus, right superior temporal gyrus and right middle temporal gyrus. CONCLUSION: The brain default mode network of PTSD patients is abnormal in resting state. These abnormalities might be the neuropathological mechanisms of PTSD.


Assuntos
Terremotos , Giro do Cíngulo/fisiopatologia , Imageamento por Ressonância Magnética , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , China , Desastres , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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