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1.
J Am Chem Soc ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39036901

RESUMO

It is well-known that magnetic moments are very harmful to superconductivity. A typical example is the element Mn, whose compounds usually exhibit strong magnetism. Thus, it is very difficult to achieve superconductivity in materials containing Mn. Here, we report enhanced superconductivity with a superconducting transition temperature (Tc) up to a record-high value of about 26 K in a beta-phase Ti1-xMnx alloy containing the rich magnetic element Mn under high pressures. This is contrary to the intuition that magnetic moments always suppress superconductivity. Under high pressures, we also found that in the middle-pressure regime, the Pauli limit of the upper critical field is surpassed. The synchrotron X-ray diffraction data show an unchanged beta-phase with a continuous contraction of the cell volume, which is well-supported by the first-principles calculations. Although the theoretical results based on electron-phonon coupling can interpret the Tc value in a certain pressure region, the monotonic enhancement of superconductivity by pressure cannot seek support from the theory. Our results show a surprising enhancement of superconductivity in the Ti1-xMnx alloy with a considerable Mn content.

2.
Nat Commun ; 15(1): 5104, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877022

RESUMO

The recent discovery of superconductivity in infinite-layer nickelate films has sparked significant interest and expanded the realm of superconductors, in which the infinite-layer structure and proper chemical doping are both of the essence. Nonetheless, the reasons for the absence of superconductivity in bulk infinite-layer nickelates remain puzzling. Herein, we investigate atomic defects and electronic structures in bulk infinite-layer Nd0.8Sr0.2NiO2 using scanning transmission electron microscopy. Our observations reveal the presence of three-dimensional (3D) block-like structural domains resulting from intersecting defect structures, disrupting the continuity within crystal grains, which could be a crucial factor in giving rise to the insulating character and inhibiting the emergence of superconductivity. Moreover, the infinite-layer structure, without complete topotactic reduction, retains interstitial oxygen atoms on the Nd atomic plane in bulk nickelates, possibly further aggravating the local distortions of NiO2 planes and hindering the superconductivity. These findings shed light on the existence of structural and atomic defects in bulk nickelates and provide valuable insights into the influence of proper topotactic reduction and structural orders on superconductivity.

3.
Sci Rep ; 14(1): 9580, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671053

RESUMO

Kagome superconductors AV3Sb5 (A = K, Rb, and Cs) have attracted enormous interest due to the coexistence of charge density wave (CDW) order, unconventional superconductivity (SC) and anomalous Hall effect (AHE). In this paper, we reported an intensive investigation on Cs(V1-xTax)3Sb5 single crystals with systematic Ta doping. Ta was confirmed to be doped into V-site in the Kagome layer from both single crystal X-ray diffraction structural refinement and scanning transmission electron microscopy observation. The highest Ta doping level was found to be about 16%, which is more than twice as much as 7% in Nb-doped CsV3Sb5. With the increase of Ta doping, CDW order was gradually suppressed and finally vanished when the doping level reached to more than 8%. Meanwhile, superconductivity was enhanced with a maximum critical temperature (Tc) of 5.3 K, which is the highest Tc in the bulk crystal of this Kagome system at ambient pressure so far. The µ0Hc2(T) behavior demonstrates that the system is still a two-band superconductor after Ta doping. Based on the electrical transport measurement, a phase diagram was set up to exhibit the evolution of CDW and SC in the Cs(V1-xTax)3Sb5 system. These findings pave a new way to search for new superconductors with higher Tc in the AV3Sb5 family and establish a new platform for tuning and controlling the multiple orders and superconducting states.

4.
Curr Med Sci ; 44(2): 355-368, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38570439

RESUMO

OBJECTIVE: Osteoarthritis (OA) is a degenerative joint disorder characterized by the gradual degradation of joint cartilage and local inflammation. This study aimed to investigate the anti-OA effect of scutellarein (SCU), a single-unit flavonoid compound obtained from Scutellaria barbata D. Don, in rats. METHODS: The extracted rat chondrocytes were treated with SCU and IL-1ß. The chondrocytes were divided into control group, IL-1ß group, IL-1ß+SCU 50 µmol/L group, and IL-1ß+SCU 100 µmol/L group. Morphology of rat chondrocytes was observed by toluidine blue and safranin O staining. CCK-8 method was used to detect the cytotoxicity of SCU. ELISA, qRT-PCR, Western blotting, immunofluorescence, SAß-gal staining, flow cytometry, and bioinformatics analysis were applied to evaluate the effect of SCU on rat chondrocytes under IL-1ß intervention. Additionally, anterior cruciate ligament transection (ACL-T) was used to establish a rat OA model. Histological changes were detected by safranin O/fast green, hematoxylin-eosin (HE) staining, and immunohistochemistry. RESULTS: SCU protected cartilage and exhibited anti-inflammatory effects via multiple mechanisms. Specifically, it could enhance the synthesis of extracellular matrix in cartilage cells and inhibit its degradation. In addition, SCU partially inhibited the nuclear factor kappa-B/mitogen-activated protein kinase (NF-κB/MAPK) pathway, thereby reducing inflammatory cytokine production in the joint cartilage. Furthermore, SCU significantly reduced IL-1ß-induced apoptosis and senescence in rat chondrocytes, further highlighting its potential role in OA treatment. In vivo experiments revealed that SCU (at a dose of 50 mg/kg) administered for 2 months could significantly delay the progression of cartilage damage, which was reflected in a lower Osteoarthritis Research Society International (OARSI) score, and reduced expression of matrix metalloproteinase 13 (MMP13) in cartilage. CONCLUSION: SCU is effective in the therapeutic management of OA and could serve as a potential candidate for future clinical drug therapy for OA.


Assuntos
Apigenina , Condrócitos , Osteoartrite , Ratos , Animais , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Inflamação/patologia , Cartilagem
5.
Clin Genitourin Cancer ; 22(3): 102062, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38548487

RESUMO

BACKGROUND: Although a survival benefit was observed in patients with metastatic renal cell carcinoma (mRCC) who underwent cytoreductive nephrectomy (CN), there is a lack of effective tools for predicting which individuals are likely to benefit from surgical intervention. Herein, we developed a predictive model using data from the Surveillance, Epidemiology, and End Results (SEER) database. MATERIALS AND METHODS: Patients diagnosed with mRCC were screened from the SEER database (2010-2020), supplemented by patients from East Asia. Patients were categorized into surgical and non-surgical groups, with propensity score matching conducted to balance baseline characteristics. Logistic regression analysis was performed to identify independent factors associated with benefits and a nomogram was constructed based on these factors. RESULTS: This study included 11,044 cases from the SEER database and 50 cases from an external validation cohort. CN was identified as an independent protective factor for OS. A nomogram was established, and it performed well in the training and validation sets. The calibration curves and DCA confirmed that the nomogram model could precisely predict the probability of surgical benefit. We used the nomogram to classify surgical patients into benefit and non-benefit groups. Then, we found that OS was significantly higher in the benefit group than in the non-benefit group. The external validation cohort observed the same result (P=0.035). CONCLUSION: While CN offers potential benefits for patients with mRCC, its applicability varies across the patient population. Our study constructed a nomogram that quantitatively assesses the likelihood of surgical benefit in mRCC patients, facilitating more tailored therapeutic decision-making.


Assuntos
Carcinoma de Células Renais , Procedimentos Cirúrgicos de Citorredução , Neoplasias Renais , Nefrectomia , Nomogramas , Programa de SEER , Humanos , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Nefrectomia/métodos , Masculino , Feminino , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Idoso , Seleção de Pacientes , Pontuação de Propensão , Prognóstico
6.
Injury ; 54(8): 110842, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37296009

RESUMO

BACKGROUND AND PURPOSE: Fracture comminution occurs in 83.9%-94% of vertical femoral neck fractures (VFNFs), the majority of which were located in posterior-inferior region, and poses a clinical challenge in fixation stability. We conducted a subject-specific finite element analysis to determine the biomechanical features and optimal fixation selection for treating VFNF with posterior-inferior comminution. PATIENTS AND METHODS: Eighteen models with three fracture types (VFNF without comminution [NCOM], with comminution [COM], with comminution + osteoporosis [COMOP]) and six internal fixation types (alpha [G-ALP], buttress [G-BUT], rhomboid [G-RHO], dynamic hip screw [G-DHS], invert triangle [G-ITR], femoral neck system (G-FNS)) were created based on the computed tomography data. By using the subject-specific finite element analysis method, stiffness, implant stress, yielding rate (YR) were compared. Additionally, in order to elucidate distinct biomechanical characters of different fracture types and fixation strategies, we calculated interfragmentary movement (IFM), detached interfragmentary movement (DIM), shear interfragmentary movement (SIM) of all fracture surface nodes. RESULTS: Generally, in comparison with NCOM, COM showed a 30.6% reduction of stiffness and 1.46-times higher mean interfragmentary movement. Besides, COM had a 4.66-times (p = 0.002) higher DIM at the superior-middle position, but similar SIM across fracture line, which presented as varus deformation. In COM and COMOP, among all six fixation strategies, G-ALP had significantly the lowest IFM (p<0.001) and SIM (p<0.001). Although G-FNS had significantly highest IFM and SIM (p<0.001), it had the highest stiffness and lowest DIM (p<0.001). In COMOP, YR was the lowest in G-FNS (2.67%). CONCLUSIONS: Posterior-inferior comminution primarily increases superior-middle detached interfragmentary movement in VFNF, which results in varus deformation. For comminuted VFNF with or without osteoporosis, alpha fixation has the best interfragmentary stability and anti-shear property among six current mainstream fixation strategies, but a relatively weaker stiffness and anti-varus property compared to fixed-angle devices. FNS is advantageous owing to stiffness, anti-varus property and bone yielding rate in osteoporosis cases, but is insufficient in anti-shear property.


Assuntos
Fraturas do Colo Femoral , Fraturas Cominutivas , Osteoporose , Humanos , Fixação Interna de Fraturas/métodos , Parafusos Ósseos , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/cirurgia , Colo do Fêmur , Fraturas Cominutivas/diagnóstico por imagem , Fraturas Cominutivas/cirurgia , Análise de Elementos Finitos , Fenômenos Biomecânicos
7.
Nature ; 620(7972): 72-77, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37168015

RESUMO

A recent study demonstrated near-ambient superconductivity in nitrogen-doped lutetium hydride1. This stimulated a worldwide interest in exploring room-temperature superconductivity at low pressures. Here, by using a high-pressure and high-temperature synthesis technique, we have obtained nitrogen-doped lutetium hydride (LuH2±xNy), which has a dark-blue colour and a structure with the space group [Formula: see text] as evidenced by X-ray diffraction. This structure is the same as that reported in ref. 1, with a slight difference in lattice constant. Raman spectroscopy of our samples also showed patterns similar to those observed in ref. 1. Energy-dispersive X-ray spectroscopy confirmed the presence of nitrogen in the samples. We observed a metallic behaviour from 350 K to 2 K at ambient pressure. On applying pressures from 2.1 GPa to 41 GPa, we observed a gradual colour change from dark blue to violet to pink-red. By measuring the resistance at pressures ranging from 0.4 GPa to 40.1 GPa, we observed a progressively improved metallic behaviour; however, superconductivity was not observed above 2 K. Temperature dependence of magnetization at high pressure shows a very weak positive signal between 100 K and 320 K, and the magnetization increases with an increase in magnetic field at 100 K. All of these are not expected for superconductivity above 100 K. Thus, we conclude the absence of near-ambient superconductivity in this nitrogen-doped lutetium hydride at pressures below 40.1 GPa.

8.
Adv Mater ; 35(26): e2301021, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36944139

RESUMO

Carbonates (CO3 2- ) have always been known as impurities to degrade the superconductivity in cuprate high-Tc superconductors. Herein, the atomic arrangement of carbonates is directly visualized in (Cu,C)Ba2 Ca3 Cu4 O11+δ via integrated differential phase contrast (iDPC) combined with state-of-the-art scanning transmission electron microscopy. The carbon atoms replace Cu atoms in the charge-reservoir layers, contributing to the formation of carbonates through strong orbital hybridization with the surrounding oxygen atoms. Using first-principles calculations, the spatial configuration of the carbonate groups is confirmed and their influence on the local crystal lattice and electronic states is further investigated. The carbonates not only accommodate distortions by improving the flatness of the outer CuO2 layers but also reduce the density of states at the Fermi level. These two factors play competitive roles to affect the superconductivity. This study provides direct evidence of the presence of CO3 2- groups and gains an insight into the underlying mechanism of superconductivity in oxycarbonate superconductors.

9.
Chinese Journal of Burns ; (6): 45-52, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-971148

RESUMO

Objective: To explore the family rehabilitation model for children with scar contracture after hand burns and observe its efficacy. Methods: A retrospective non-randomized controlled study was conducted. From March 2020 to March 2021, 30 children with scar contracture after deep partial-thickness to full-thickness burns of hands, who met the inclusion criteria, were hospitalized in the Burn Center of PLA of the First Affiliated Hospital of Air Force Medical University. According to the rehabilitation model adopted, 18 children (23 affected hands) were included in a group mainly treated by family rehabilitation (hereinafter referred to as family rehabilitation group), and 12 children (15 affected hands) were included in another group mainly treated by hospital rehabilitation (hereinafter referred to as hospital rehabilitation group). In the former group, there were 11 males and 7 females, aged (4.8±2.1) years, who began rehabilitation treatment (3.1±0.8) d after wound healing; in the latter group, there were 7 males and 5 females, aged (4.6±2.1) years, who began rehabilitation treatment (2.8±0.7) d after wound healing. The children in hospital rehabilitation group mainly received active and passive rehabilitation training in the hospital, supplemented by independent rehabilitation training after returning home; after 1-2 weeks of active and passive rehabilitation training in the hospital, the children in family rehabilitation group received active and passive rehabilitation training at home under the guidance of rehabilitation therapists through WeChat platform. Both groups of children were treated for 6 months. During the treatment, they wore pressure gloves and used hand flexion training belts and finger splitting braces. Before treatment and after 6 months of treatment, the modified Vancouver scar scale, the total active movement of the hand method, and Carroll quantitative test of upper extremity function were used to score/rate the scar of the affected hand (with the difference of scar score between before treatment and after treatment being calculated), the joint range of motion (with excellent and good ratio being calculated), and the function of the affected limb, respectively. Data were statistically analyzed with independent sample t test, equivalence test, Fisher's exact probability test, and Mann-Whitney U test. Results: The differences of scar scores of the affected hands of children in family rehabilitation group and hospital rehabilitation group between after 6 months of treatment and those before treatment were 3.0 (2.0, 7.0) and 3.0 (2.0, 8.0) respectively (with 95% confidence interval of 2.37-5.38 and 1.95-5.91). The 95% confidence interval of the difference between the differences of the two groups was -2.43-2.21, which was within the equivalent boundary value of -3-3 (P<0.05). The excellent and good ratios of joint range of motion of the affected hand of children in family rehabilitation group and hospital rehabilitation group were 3/23 and 2/15 respectively before treatment, and 15/23 and 12/15 respectively after 6 months of treatment. The ratings of joint range of motion of the affected hand of children in family rehabilitation group and hospital rehabilitation group after 6 months of treatment were significantly higher than those before treatment (with Z values of 3.58 and 2.30, respectively, P<0.05), but the ratings of joint range of motion of the affected hand between the two groups were similar before treatment and after 6 months of treatment (with Z values of 0.39 and 0.55, respectively, P>0.05). The functional ratings of the affected limbs of children in family rehabilitation group and hospital rehabilitation group after 6 months of treatment were significantly higher than those before treatment (with Z values of 3.98 and 3.51, respectively, P<0.05), but the functional ratings of the affected limbs between the two groups were similar before treatment and after 6 months of treatment (with Z values of 1.27 and 0.38, respectively, P>0.05). Conclusions: The WeChat platform assisted rehabilitation treatment with mainly family rehabilitation, combined with hand flexion and extension brace can effectively reduce the scarring after children's hand burns, improve the joint range of motion of the affected hands, and promote the recovery of affected limb function. The effect is similar to that of hospital-based rehabilitation providing an optional rehabilitation, treatment method for children who cannot continue to receive treatment in hospital.


Assuntos
Masculino , Feminino , Humanos , Criança , Cicatriz/terapia , Estudos Retrospectivos , Resultado do Tratamento , Cicatrização , Traumatismos da Mão/reabilitação , Traumatismos do Punho , Contratura/etiologia , Queimaduras/complicações
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991860

RESUMO

Objective:To collect and analyze laboratory indicators of patients of different sexes after blood transfusion, evaluate the effectiveness of blood transfusion, and provide a theoretical basis for formulating more scientific blood transfusion plans.Methods:The clinical data of 808 patients who underwent blood transfusion in The First Affiliated Hospital of Anhui University of Science and Technology from January 2020 to December 2021 were retrospectively analyzed. According to the blood transfusion strategy and the department to which the patients were admitted, these patients were divided into four groups: surgical restrictive blood transfusion group (group A: 72 males and 69 females), surgical non-restricted blood transfusion (group B: 77 males and 118 females), medical restrictive blood transfusion (group C: 184 males and 126 females), and medical non-restricted blood transfusion (group D: 110 males and 52 females). Univariate and multivariate Logistic regression analyses were performed.Results:In group A, after blood transfusion, hemoglobin level in female patients was significantly higher than that in male patients [79.0 (71.5, 87.0) g/L vs. 75.5 (69.0, 82.8) g/L, Z = -2.18, P = 0.029], and C-reactive protein in female patients was significantly lower than that in male patients [21.3 (0.0, 56.0) mg/L vs. 37.0 (3.3, 95.5) mg/L, Z = -1.97, P = 0.049]. In groups B, C, and D, there were no significant differences in hemoglobin, C-reactive protein, and hematocrit between male and female patients (all P > 0.05). Multivariate analysis showed that the difference in hemoglobin levels between before and after blood transfusion was statistically significant ( P = 0.009). After a blood transfusion, hemoglobin level in female patients was 1.44 times that in male patients. Conclusion:The tolerance of female patients to blood loss is higher than that of male patients in surgical restrictive blood transfusion, so the threshold value of hemoglobin given to female patients during blood transfusion can be lower than that of male patients. In the case of the same blood loss, priority of blood transfusion can be given to male patients. In the case of scarce blood resources, the total amount of blood transfused for female patients can be approximately reduced.

11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-989676

RESUMO

Objective:To explore the effect of intermittent angle traction on the supine position combined with acupoint application on the changes of cervical radiculopathy related biological parameters.Methods:Randomized controlled trial. A total of 100 patients with radiculopathy cervical spondylosis treated in the Second Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine from February 2019 to February 2021 were selected and randomly divided into observation group ( n=50) and control group ( n=50). Patients in the control group were given conventional treatment with western medicine, and patients in the observation group were given acupoint application combined with supine intermittent angle traction combined with treatment. Both groups were treated for 3 months. The Japanese Orthopaedic Association Spinal Cord Function (JOA), Cervical Disability Index (NDI), Pain Visual Analogue Score (VAS) and the changes in intervertebral foramen volume of two groups were compared before and after treatment. The difference in clinical efficacy between the two groups after treatment was observed. We took a thin spiral CT film of the patient's cervical spine, established a three-dimensional finite element model of the cervical spine, and compared the differences in related indicators between the two groups before and after treatment. Results:The total effective rate was 94.0% (47/50) in the observation group and 70.0% (35/50) in the control group, and there was a significant difference between the two groups ( χ2=9.76, P=0.002). After treatment, the JOA score in the observation group was significantly higher than that of the control group ( t=6.23, P<0.01), the NDI score, VAS score were significantly lower than those in the control group ( t values were 5.17,9.13, P<0.01), the intervertebral foraminal volume [(8.45±1.27)mm 3vs. (7.18±1.38)mm 3, t=4.79] was significantly higher than that of the control group ( P<0.01), and C 4-7 cervical vertebra flexion [(7.15±0.87)° vs.(5.64±0.78)°, t=9.14], retroflexion [(8.53±0.73)° vs. (7.15±0.68)°, t=9.78], sidebend [(6.57±0.71)° vs. (5.28±0.67)°, t=9.34], rotated [(7.89±0.52)° vs. (6.54±0.48)°, t=13.49] were significantly higher than those in the control group ( P<0.01); C 4-7 disc flexion [(1.41±0.09) kPa vs. (2.01±0.12) kPa, t=28.28], retroflexion [(1.54±0.07) kPa vs. (2.01±0.08) kPa, t=31.26], sidebend [(1.24±0.07) kPa vs. (1.89±0.13) kPa, t=31.13], rotated [(1.23±0.06)kPa vs. (1.85±0.11)kPa, t=34.99] were significantly lower than those in the control group ( P<0.01). Conclusion:The supine intermittent Angle traction combined with acupoint application in the treatment of cervical spondylotic radiculopathy can relieve the neck pain, improve the neck function, restore the physiological curvature of the cervical spine, and promote the recovery of cervical biomechanics.

12.
Nano Lett ; 22(23): 9450-9456, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36441557

RESUMO

The vortex core can be regarded as a nanoscale confined system for quasiparticles in a type-II superconductor. It is very interesting to investigate the interplay between the vortex core and other microscopic quantum confined systems. We observe band-like canals with the width of about 15 nm on the surface of KCa2(Fe1-xNix)4As4F2 (x = 0.05) by scanning tunneling microscopy. Some canals suppress superconductivity and confine parallel standing waves due to the quasiparticle interference. Upon magnetic fields being applied, some elongated vortices are formed within canals showing bamboo-like one-dimensional vortex chains. Interestingly, the confined vortex cores are elongated roughly along the perpendicular direction of canals, and the local density of states at positive and negative energies shows an in-phase oscillation at zero field; but, it becomes out-of-phase crossing the vortex cores. Our work reveals a new type of vortex patterns in confined canals and its interplay with the quasiparticle interference.

13.
J Phys Condens Matter ; 34(47)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36162400

RESUMO

Chromium (Cr) is a transition metal element with 3dorbital electrons. In most compounds containing Cr, due to the correlation effect, twofold features, namely localization and itinerancy are expected. The localization gives rise to a magnetic moment, while the latter exhibits as the effective coherent weight for conductivity. Here we report the physical properties of Cr3Ru compounds with body-centered cubic (bcc) and A15 structures by using multiple experimental tools. The resistivity measurements show sharp superconducting transitions atTc= 2.77 K andTc= 3.37 K for the bcc and A15 structures, respectively. A high residual resistivity exists in both phases. Magnetization measurements also show rather narrow superconducting transitions, with a clear hump feature in the intermediate temperature region (about 150 K), which may be ascribed to the remaining antiferromagnetic spin fluctuations. A pronounced second peak effect has been observed in magnetization hysteresis loops in the superconducting state only for samples with bcc structure. The specific heat coefficient reveals a clear jump at critical temperatures (Tc). We find thats-wave gaps can be adopted to fit the low temperature specific heat data of both samples yielding ratios of2Δ/kBTcabout 3.6, indicating a moderate pairing strength. Interestingly, the Wilson ratiosRW=Aχ0/γnare 3.81 and 3.62 for the bcc and A15 phases, suggesting a moderate correlation effect of conducting electrons in the normal state. Besides, for samples with A15 structure, another specific heat anomaly occurs at about 0.85 K and is sensitive to magnetic fields. In addition, by applying high pressures, both systems will exhibit an enhancement ofTcwith a rate of about 0.019 K GPa-1and 0.013 K GPa-1for the bcc and A15 phases, respectively. Our combinatory results point to unusual behavior of both superconducting and normal states in these two Cr based alloys.

14.
BMC Surg ; 22(1): 308, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948902

RESUMO

BACKGROUND: Natural orifice specimen extraction surgery (NOSES) has the advantages of less postoperative pain, fast bowel function recovery, reduced hospital stay and better cosmetic effects. In our centre, anterior resection of rectal cancer with preservation of the left colonic artery (LCA) was performed using NOSES. The feasibility, safety and short-term clinical efficacy of the technique were discussed. METHODS: A retrospective analysis was performed on 19 patients who underwent laparoscopic anterior resection of rectal cancer with left colonic artery preservation and natural orifice specimen extraction in the Gastrointestinal Surgery Center of Sichuan Cancer Hospital from September 2018 to December 2019. General information about the patients, perioperative data and short-term postoperative results were analysed. RESULTS: All operations were completed smoothly, with an average operation duration of 304.36 ± 45.04 min, intraoperative bleeding of 76.31 ± 61.12 ml, first time off bed of 14.42 ± 3.56 h, first time to anus exhaust of 15.26 ± 8.92 h, first time to liquid diet of 2.94 ± 1.12 days, and average postoperative stay of 10.21 ± 3.13 days. Two patients developed temporary intestinal obstruction, and one patient developed pulmonary infection. All of them recovered well after active supportive treatment and were successfully discharged. CONCLUSION: Laparoscopic NOSES for rectal cancer with left colon artery preservation is safe and feasible, with satisfactory short-term results, and is worthy of further clinical investigation.


Assuntos
Laparoscopia , Cirurgia Endoscópica por Orifício Natural , Neoplasias Retais , Artérias , Colo , Estudos de Viabilidade , Humanos , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
15.
Nat Commun ; 13(1): 3461, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710635

RESUMO

The kagome lattice provides a fertile platform to explore novel symmetry-breaking states. Charge-density wave (CDW) instabilities have been recently discovered in a new kagome metal family, commonly considered to arise from Fermi-surface instabilities. Here we report the observation of Raman-active CDW amplitude modes in CsV3Sb5, which are collective excitations typically thought to emerge out of frozen soft phonons, although phonon softening is elusive experimentally. The amplitude modes strongly hybridize with other superlattice modes, imparting them with clear temperature-dependent frequency shift and broadening, rarely seen in other known CDW materials. Both the mode mixing and the large amplitude mode frequencies suggest that the CDW exhibits the character of strong electron-phonon coupling, a regime in which phonon softening can cease to exist. Our work highlights the importance of the lattice degree of freedom in the CDW formation and points to the complex nature of the mechanism.

16.
Innovation (Camb) ; 3(1): 100202, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35059683

RESUMO

Superconductivity has been discovered recently in infinite-layer nickel-based 112 thin films R 1-x A xNiO2 (R = La, Nd, Pr and A = Sr, Ca). They are isostructural to the infinite-layer cuprate (Ca,Sr)CuO2 and are supposed to have a formal Ni 3d 9 valence, thus providing a new platform to study the unconventional pairing mechanism of high-temperature superconductors. This important discovery immediately triggers a huge amount of innovative scientific curiosity in the field. In this paper, we try to give an overview of the recent research progress on the newly found superconducting nickelate systems, both from experimental and theoretical aspects. We mainly focus on the electronic structures, magnetic excitations, phase diagrams and superconducting gaps, and finally make some open discussions for possible pairing symmetries in Ni-based 112 systems.

17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-928958

RESUMO

OBJECTIVE@#To explore the influences of andrographolide (Andro) on bladder cancer cell lines and a tumor xenograft mouse model bearing 5637 cells.@*METHODS@#For in vitro experiments, T24 cells were stimulated with Andro (0-40 µmol/L) and 5637 cells were stimulated with Andro (0 to 80 µmol/L). Cell growth, migration, and infiltration were assessed using cell counting kit-8, colony formation, wound healing, and transwell assays. Apoptosis rate was examined using flow cytometry. In in vivo study, the antitumor effect of Andro (10 mg/kg) was evaluated by 5637 tumor-bearing mice, and levels of nuclear factor κ B (NF- κ B) and phosphoinositide 3-kinase/AKT related-proteins were determined by immunoblotting.@*RESULTS@#Andro suppressed growth, migration, and infiltraion of bladder cancer cells (P⩽0.05 or P⩽0.01). Additionally, Andro induced intrinsic mitochondria-dependent apoptosis in bladder cancer cell lines. Furthermore, Andro inhibited bladder cancer growth in mice (P⩽0.01). The expression of p65, p-AKT were suppressed by Andro treatment in vitro and in vivo (P⩽0.05 or P⩽0.01).@*CONCLUSIONS@#Andrographolide inhibits proliferation and promotes apoptosis in bladder cancer cells by interfering with NF- κ B and PI3K/AKT signaling in vitro and in vivo.


Assuntos
Animais , Humanos , Camundongos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Diterpenos/uso terapêutico , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico
18.
Journal of Forensic Medicine ; (6): 579-583, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-984149

RESUMO

OBJECTIVES@#To study the cooling reaction kinetic characteristics of the temperature difference between cadaver temperature and ambient temperature (hereinafter referred to as "cadaver temperature difference") according to the reaction kinetics method.@*METHODS@#Thirty rabbits were randomly divided into 5 groups with 6 rabbits in each group. The rabbits were injected with 10% potassium chloride solution intravenously. After death, the rabbits were placed at 5 ℃, 10 ℃, 15 ℃, 20 ℃ and 25 ℃ environment condition, respectively, and the rectal temperature was measured every minute for 20 hours. The measured cadaver temperature was subtracted from ambient temperature, and the cadaver temperature difference data was calculated using the reaction kinetics formula. The linear regression equation was fitted for analysis, and the experimental results were applied to the temperature difference data of human body after death for verification.@*RESULTS@#Under different environmental conditions, the linear coefficient determination of temperature difference -ln(C/C0) in rabbits was 0.99, showing a good linear relationship with time t. The application of human body temperature data after death was consistent with the results of animal experiments.@*CONCLUSIONS@#Under stable conditions, the temperature difference cooling process after death in rabbits is a first-order kinetic response. The method can also be used to study the temperature difference in human body after death.


Assuntos
Animais , Humanos , Coelhos , Temperatura Corporal , Temperatura , Cinética , Cadáver
19.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-920350

RESUMO

@#BACKGROUND: The quick sequential organ failure assessment (qSOFA) is recommended to identify sepsis and predict sepsis mortality. However, some studies have recently shown its poor performance in sepsis mortality prediction. To enhance its effectiveness, researchers have developed various revised versions of the qSOFA by adding other parameters, such as the lactate-enhanced qSOFA (LqSOFA), the procalcitonin-enhanced qSOFA (PqSOFA), and the modified qSOFA (MqSOFA). This study aimed to compare the performance of these versions of the qSOFA in predicting sepsis mortality in the emergency department (ED). METHODS: This retrospective study analyzed data obtained from an electronic register system of adult patients with sepsis between January 1 and December 31, 2019. Receiver operating characteristic (ROC) curve analyses were performed to determine the area under the curve (AUC), with sensitivity, specificity, and positive and negative predictive values calculated for the various scores. RESULTS: Among the 936 enrolled cases, there were 835 survivors and 101 deaths. The AUCs of the LqSOFA, MqSOFA, PqSOFA, and qSOFA were 0.740, 0.731, 0.712, and 0.705, respectively. The sensitivity of the LqSOFA, MqSOFA, PqSOFA, and qSOFA were 64.36%, 51.40%, 71.29%, and 39.60%, respectively. The specificity of the four scores were 70.78%, 80.96%, 61.68%, and 91.62%, respectively. The LqSOFA and MqSOFA were superior to the qSOFA in predicting in-hospital mortality. CONCLUSIONS: Among patients with sepsis in the ED, the performance of the PqSOFA was similar to that of the qSOFA and the values of the LqSOFA and MqSOFA in predicting in-hospital mortality were greater compared to qSOFA. As the added parameter of the MqSOFA was more convenient compared to the LqSOFA, the MqSOFA could be used as a candidate for the revised qSOFA to increase the performance of the early prediction of sepsis mortality.

20.
Chinese Journal of Burns ; (6): 328-334, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936014

RESUMO

Objective: To explore the clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 11 patients with cervical cicatrix contracture deformity after burns who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University, including 3 males and 8 females, aged 5 to 46 years, with a course of cervical cicatrix contracture deformity of 5 months to 8 years. The degree of cervical cicatrix contracture deformity was degree Ⅰ in one patient, degree Ⅱ in nine patients, and degree Ⅲ in one patient. In the first stage, according to the sizes of neck scars, one rectangular skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 200 to 600 mL was placed in the back. The expansion time was 4 to 12 months with the total normal saline injection volume being 3.0 to 3.5 times of the rated capacity of expander. In the second stage, free expanded thoracodorsal artery perforator flaps with areas of 10 cm×7 cm to 24 cm×13 cm were cut out to repair the wounds with areas of 9 cm×6 cm to 23 cm×12 cm which was formed after cervical cicatectomy. The main trunk of thoracodorsal artery and vein were selected for end-to-end anastomosis with facial artery and vein, and the donor sites were directly closed. The survival of flaps and healing of flap donor sites were observed on the 14th day post surgery. The appearances and cicatrix contracture deformity of the flaps, recovery of cervical function, and scar hyperplasia of donor sites were followed up. Results: On the 14th day post surgery, the flaps of ten patients survived, while ecchymosis and epidermal necrosis occurred in the center of flap of one patient and healed 2 weeks after dressing change. On the 14th day post surgery, the flap donor sites of 11 patients all healed well. During the follow-up of 6-12 months post surgery, the flaps of ten patients were similar to the skin around the recipient site in texture and color, while the flap of one patient was slightly swollen. All of the 11 patients had good recovery of cervical function and no obvious scar hyperplasia nor contracture in the flaps or at the donor sites. Conclusions: Application of expanded thoracodorsal artery perforator flaps can restore the appearance and function of the neck, and cause little damage to the donor site in reconstructing the cervical cicatrix contracture deformity after burns, which is worthy of clinical reference and application.


Assuntos
Feminino , Humanos , Masculino , Artérias , Queimaduras/cirurgia , Cicatriz/cirurgia , Contratura/cirurgia , Hiperplasia , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento
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