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1.
Nat Mater ; 23(3): 347-355, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37443381

RESUMO

Transition metal dichalcogenide (TMD) nanotubes offer a unique platform to explore the properties of TMD materials at the one-dimensional limit. Despite considerable efforts thus far, the direct growth of TMD nanotubes with controllable chirality remains challenging. Here we demonstrate the direct and facile growth of high-quality WS2 and WSe2 nanotubes on Si substrates using catalytic chemical vapour deposition with Au nanoparticles. The Au nanoparticles provide unique accommodation sites for the nucleation of WS2 or WSe2 shells on their surfaces and seed the subsequent growth of nanotubes. We find that the growth mode of nanotubes is sensitive to the temperature. With careful temperature control, we realize ~79% WS2 nanotubes with single chiral angles, with a preference of 30° (~37%) and 0° (~12%). Moreover, we demonstrate how the geometric, electronic and optical properties of the synthesized WS2 nanotubes can be modulated by the chirality. We anticipate that this approach using Au nanoparticles as catalysts will facilitate the growth of TMD nanotubes with controllable chirality and promote the study of their interesting properties and applications.

2.
Biochem Biophys Res Commun ; 715: 149999, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38678787

RESUMO

Non-alcoholic fatty liver disease (NAFLD), a chronic liver condition and metabolic disorder, has emerged as a significant health issue worldwide. D-mannose, a natural monosaccharide widely existing in plants and animals, has demonstrated metabolic regulatory properties. However, the effect and mechanism by which D-mannose may counteract NAFLD have not been studied. In this study, network pharmacology followed by molecular docking analysis was utilized to identify potential targets of mannose against NAFLD, and the leptin receptor-deficient, genetically obese db/db mice was employed as an animal model of NAFLD to validate the regulation of D-mannose on core targets. As a result, 67 targets of mannose are predicted associated with NAFLD, which are surprisingly centered on the mechanistic target of rapamycin (mTOR). Further analyses suggest that mTOR signaling is functionally enriched in potential targets of mannose treating NAFLD, and that mannose putatively binds to mTOR as a core mechanism. Expectedly, repeated oral gavage of supraphysiological D-mannose ameliorates liver steatosis of db/db mice, which is based on suppression of hepatic mTOR signaling. Moreover, daily D-mannose administration reduced hepatic expression of lipogenic regulatory genes in counteracting NAFLD. Together, these findings reveal D-mannose as an effective and potential NAFLD therapeutic through mTOR suppression, which holds translational promise.


Assuntos
Manose , Farmacologia em Rede , Hepatopatia Gordurosa não Alcoólica , Serina-Treonina Quinases TOR , Animais , Camundongos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Manose/farmacologia , Manose/metabolismo , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
3.
Small ; 19(15): e2206947, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36631255

RESUMO

Two large barriers are impeding the wide implementation of electric vehicles, namely driving-range and cost, primarily due to the low specific energy and high cost of mono-valence cathodes used in lithium-ion batteries. Iron is the ideal element for cathode materials considering its abundance, low cost and toxicity. However, the poor reversibility of (de)lithiation and low electronic conductivity prevent iron-based high specific energy multi-valence conversion cathodes from practical applications. In this work, a sustainable FeOF nanocomposite is developed with extraordinary performance. The specific capacity and energy reach 621 mAh g-1 and 1124 Wh kg-1 with more than 100 cycles, which triples the specific capacity, and doubles the specific energy of current mono-valence intercalation LiCoO2 . This is the result of an effective approach, combing the nanostructured FeOF with graphene, realized by making the (de)lithiation reversible by immobilizing FeOF nanoparticles and the discharge products over the graphene surface and providing the interparticle electric conduction. Importantly, it demonstrates that introducing small amount of graphene can create new materials with desired properties, opening a new avenue for altering the (de)lithiation process. Such extraordinary performance represents a significant breakthrough in developing sustainable conversion materials, eventually overcoming the driving range and cost barriers.

4.
Chin J Traumatol ; 24(3): 159-168, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33678536

RESUMO

PURPOSE: This meta-analysis compared the clinical outcome of three-dimensional (3D) printing combined with open reduction and internal fixation (ORIF) to traditional ORIF in the treatment of acetabular fractures. METHODS: We searched the Cochrane Library, PubMed, Embase, VIP database, CNKI, and Wanfang database with keywords "acetabular fracture", "3D printing", "three-dimensional printing", "open reduction and internal fixation", "Acetabulum", "Acetabula" from January 2000 to March 2020. Two reviewers independently selected articles, extracted data, assessed the quality evidence and risk bias of included trials using the Cochrane Collaboration' s tools and/or Newcastle-Ottawa scale. When the two analysts had different opinions, they would ask the third analyst for opinion. Randomized controlled trials or retrospective comparative studies of 3D printing combined with ORIF (3D printing group) versus traditional ORIF (conventional group) in the treatment of acetabular fractures were selected. The data of operation time, intraoperative blood loss, intraoperative fluoroscopy times, incidence of complications, excellent and good rate of Matta score for reduction, and excellent and good rate of hip function score were extracted. Stata14.0 statistical software was used for data analysis. RESULTS: Altogether 9 articles were selected, including 5 randomized controlled trials and 4 retrospective studies. A total of 467 patients were analyzed, 250 in the conventional group, and 217 in the 3D printing group. The operation time in the 3D printing group was less than that in the conventional group and the difference was statistically significant (standardized mean difference (SMD) = -1.19, 95% CI: -1.55 to -0.82, p < 0.05). The intraoperative bleeding volume of the 3D printing group was significantly lower than that of the conventional group (SMD = -1.08, 95% CI: -1.65 to -0.51, p < 0.05). The fluoroscopy times were less in the 3D printing group than in the conventional group and the difference was statistically significant (SMD = -1.64, 95% CI: -2.35 to -0.93, p < 0.05). The total incidence of complications in the 3D printing group was significantly lower than that in the conventional group (OR = 0.43, 95% CI: 0.24-0.79, p < 0.05). There was no significant difference in the excellent and good rate of Matta score for reduction between the two groups (OR = 0.60, 95% CI: 0.34-1.06, p > 0.05). There was no significant difference in the excellent and good rate of hip function score at the end of postoperative follow-up between the two groups (OR = 0.84, 95% CI: 0.46-1.56, p > 0.05), but the follow-up time varies from 6 months to 40 months. CONCLUSION: Compared with traditional ORIF, 3D printing combined with ORIF has certain advantages in terms that 3D printing not only helps surgeons to understand acetabular fractures more intuitively, but also effectively reduces operation time, intraoperative blood loss, intraoperative fluoroscopy times, and postoperative complications. However, there were no significant differences in the excellent and good rate of Matta score for reduction and the excellent and good rate of hip function score at the end of follow-up.


Assuntos
Fixação Interna de Fraturas , Redução Aberta , Humanos , Impressão Tridimensional , Estudos Retrospectivos , Resultado do Tratamento
5.
J Int Med Res ; 51(7): 3000605231187938, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37498225

RESUMO

OBJECTIVE: Methylene blue (MB) and spring microcoils are used for the preoperative localization of small pulmonary nodules (SPNs). We aimed to compare the efficacy and safety of these methods using published data. METHODS: We identified randomized controlled trials and observational studies that assessed preoperative SPN localization using MB or spring microcoil and compared these using a meta-analysis. RESULTS: Seven studies of 933 patients were identified, in whom 1081 SPNs were located. Four hundred twenty-four SPNs were located using MB (n = 359 participants), and 657 SPNs were located using the spring microcoil method (n = 574 participants). The prevalence of technical success of SPN localization was higher using MB (mean deviation [MD]: 0.43; 95% confidence interval [CI]: 0.20, 0.93); the incidence of postoperative complications was lower (MD: 1.70; 95% CI: 1.09, 2.65); and the time taken for removal was longer (MD: -12.37; 95% CI: -22.60, -2.13). There were no differences with respect to the successful wedge resection rate, the time taken for localization, the duration of the procedure, or the mean hospital stay. CONCLUSIONS: Both methods can detect SPNs; however, MB is associated with a higher success rate and fewer postoperative complications, while spring microcoil localization is associated with more rapid removal.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Azul de Metileno , Tomografia Computadorizada por Raios X , Cirurgia Torácica Vídeoassistida/métodos , Resultado do Tratamento , Nódulos Pulmonares Múltiplos/cirurgia , Complicações Pós-Operatórias , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/cirurgia , Estudos Retrospectivos
6.
J Ethnopharmacol ; 315: 116718, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37268258

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The root of Atractylodes macrocephala Koidz. (AM) has been used for thousands of years in China, and it's extracts contain various constituents, such as volatile oils, polysaccharides, and lactones, with a myriad of pharmacological effects, including improves the healthy state of the gastrointestinal system and regulating immunity, hormone secretion, anti-inflammatory, antibacterial, antioxidation, anti-aging, and antitumor properties. Recently, researchers have focused on the effect of AM in regulating bone mass; therefore, its potential mechanism of action in regulating bone mass needs to be elucidated. AIM OF REVIEW: This study reviewed the known and possible mechanisms of bone mass regulation by AM. MATERIALS AND METHODS: Cochrane, Medline via PubMed, Embase, CENTRAL, CINAHL, Web of Science, Chinese biomedical literature database, Chinese Science and Technology Periodical Database, and Wanfang Database were used to search AM root extracts-related studies. The retrieval date was from the establishment of the database to January 1, 2023. RESULTS: By summarizing 119 natural active substances that have been isolated from AM root to date, we explored its possible targets and pathways (such as Hedgehog, Wnt/ß-catenin, and BMP/Smads pathways etc.) for bone growth and presented our position on possible future research/perspectives in the regulation of bone mass using this plant. CONCLUSIONS: AM root extracts (incuding aqueous, ethanol etc.) promotes osteogenesis and inhibits osteoclastogenesis. These functions promote the absorption of nutrients, regulate gastrointestinal motility and intestinal microbial ecology, regulate endocrine function, strengthen bone immunity, and exert anti-inflammatory and antioxidant effects.


Assuntos
Atractylodes , Óleos Voláteis , China , Extratos Vegetais/farmacologia , Anti-Inflamatórios/farmacologia
7.
Orthop Surg ; 14(6): 1034-1048, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35524654

RESUMO

Tibial cortex transverse transport (TTT) surgery is an extension of the Ilizarov technique. Based on the law of tension-stress, its primary function is to rebuild microcirculation which can relieve ischemic symptoms and promote wound healing. It has received more and more scholars' attention and has experienced a series of changes for 20 years since it entered PR China. The mechanisms involved have gradually become clear, such as the reconstruction of the polarization balance of macrophages, the promotion of vascular tissue regeneration, and the mobilization and regulation of bone marrow-derived stem cells. TTT technique is mainly used in the treatment of chronic ischemic diseases of the lower extremities. It has recently been successfully used in the treatment of primary lymphedema of the lower extremities. A series of improvements have been made in the external fixator's style, the size of skin incision and osteotomy, and distraction method. For example, the annular external fixator has been redesigned as a unilateral external fixator, and accordion technology has been introduced. For distraction methods after surgery, there was no uniform standard in the past. The technique can also be used in combination with other treatments to achieve better effects, such as interventional therapy, negative pressure sealed drainage, 3D printing technology, traditional Chinese medicine. Nevertheless, the surgery may bring some complications, such as secondary fracture, nail infection, skin necrosis at the surgical site, etc. Reports of complications and doubts about the technique have made the TTT technique controversial. In 2020, the relevant expert consensus was published with treatment and management principles, which might guide the better application and development of this technique.


Assuntos
Técnica de Ilizarov , Fraturas da Tíbia , Fixadores Externos , Humanos , Extremidade Inferior , Tíbia/cirurgia , Fraturas da Tíbia/cirurgia , Resultado do Tratamento , Cicatrização
8.
Zhongguo Gu Shang ; 35(12): 1200-6, 2022 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-36572440

RESUMO

Knee joint distraction is a new technology for the treatment of knee osteoarthritis in recent years. It could reduce knee pain and improve knee function, which is inseparable from the role of cartilage repair. The mechanism and influencing factors of knee joint distraction in repairing cartilage are the focus of current research. In this paper, the author reviewed literature and found that knee joint distraction could reduce knee joint load and provide a appropriate mechanical environment for cartilage repair, and it is resulting hydrostatic pressure fluctuation in the knee joint not only helps cartilage to absorb nutrients, but also promotes cartilage formation genes and inhibits cartilage matrix degrading enzyme gene expression. In addition, knee joint distraction creates conditions for synovial mesenchymal stem cells to be collected to cartilage injury, and improves ability of synovial mesenchymal stem cells to proliferate and differentiate into a chondrogenic lineage. Knee joint distraction could reduce inflammatory reaction and cartilage injury of knee joint by reducing content of inflammatory factors and inhibiting expression of inflammatory genes. At present, it is known that the factors affect repair of cartilage by knee joint distraction include, increasing weight-bearing activity and height and time of distraction is helpful for cartilage repair, male patients and patients with higher severity of knee osteoarthritis have better cartilage repair effect after knee joint distraction.The better efficacy of cartilage repair on the first year after knee joint distraction predicts a higher long-term survival rate of knee joint distraction with knee preservation. However, the research on the above hot spots is only at the initial stage and further exploration is still needed, in order to better guide clinical application of knee joint distraction.


Assuntos
Cartilagem Articular , Osteoartrite do Joelho , Osteogênese por Distração , Humanos , Masculino , Fixadores Externos , Articulação do Joelho/cirurgia , Osteogênese por Distração/métodos , Cartilagem , Cartilagem Articular/cirurgia
9.
Geriatr Orthop Surg Rehabil ; 13: 21514593221107509, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35721367

RESUMO

Purpose: Posterior short-segment fixation (SSF) and long-segment fixation (LSF) are two methods for the treatment of Kummell disease, but the safety and effectiveness of these two surgical methods still lack adequate medical evidence. This study aimed to evaluate the two methods. Methods: Database searches for randomized controlled trials, case-control studies, and cohort studies of posterior SSF and posterior LSF in the treatment of Kummell disease were performed. After the document quality was evaluated with the Newcastle-Ottawa Quality Assessment Scale, a meta-analysis was carried out. Results: Meta-analysis revealed that the operation time and intraoperative blood loss in the LSF group were higher than those in the SSF group [MD = -18.17, 95% CI (-30.31, -6.03), z = 2.93, P = .003; MD = -82.07, 95% CI (-106.91, -57.24], z = 6.48, P < .00001). The postoperative last follow-up local kyphosis angle in the SSF group was greater than that in the LSF group (MD = 3.18, 95% CI [.56, 5.81], z = 2.38, P = .02), and there were no significant differences in perioperative complications, bone cement leakage rate, incidence of adverse events during follow-up, postoperative follow-up visual analog scale, postoperative Oswestry dysfunction index, and postoperative immediate local kyphosis angle between the two groups (P > .05). Conclusion: SSF and LSF are effective and safe for the treatment of Kummell disease. SSF can reduce the operation time and intraoperative bleeding; LSF can better maintain the long-term stability of kyphosis. The methods should be evaluated by clinicians according to the individual situation of the patients.

10.
ACS Appl Mater Interfaces ; 13(1): 18-33, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382579

RESUMO

Li metal has been widely recognized as a promising anode candidate for high-energy-density batteries. However, the inherent limitations of Li metal, that is, the low Coulombic efficiency and dendrite issues, make it still far from practical applications. In short, the low Coulombic efficiency shortens the cycle life of Li metal batteries, while the dendrite issue raises safety concerns. Thanks to the great efforts of the research community, prolific fundamental understanding as well as approaches for mitigating Li metal anode safety have been extensively explored. In this Review, Li electrochemical deposition behaviors have been systematically summarized, and recent progress in electrode design and electrolyte system optimization is reviewed. Finally, we discuss the future directions, opportunities, and challenges of Li metal anodes.

11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(8): 994-999, 2020 Aug 15.
Artigo em Zh | MEDLINE | ID: mdl-32794668

RESUMO

OBJECTIVE: To summarize the research progress of tibial transverse transport (TTT) in treatment of chronic ischemic diseases of the lower extremities. METHODS: The related literature was systematically searched and the mechanisms, clinical treatment methods, clinical efficacy, indications, contraindications, and complications of TTT were discussed. RESULTS: Based on the law of tension-stress, TTT is a new method in the treatment of chronic ischemic diseases of the lower extremities. It can relieve the ischemic symptoms, promote the wound healing, and increase the limb salvage rate. The clinical application in recent years has shown good effectiveness, and the scope of application is expanding. CONCLUSION: Due to the current limited clinical application, the sample size of the TTT for the chronic ischemic diseases of the lower extremities is relatively small, and the follow-up time is limited. So its validity, long-term effectiveness, and bone transport standards are need further research.


Assuntos
Técnica de Ilizarov , Fraturas da Tíbia/cirurgia , Humanos , Isquemia/cirurgia , Salvamento de Membro , Extremidade Inferior , Tíbia/cirurgia , Resultado do Tratamento
12.
Orthop Surg ; 12(4): 1053-1064, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32691520

RESUMO

OBJECTIVE: To evaluate the clinical efficacy of internal fixation versus hemiarthroplasty in the treatment of unstable intertrochanteric fractures in the elderly. METHODS: A search was conducted in PubMed, Web of Science, Embase, and Cochrane Library databases up to April 2020. The present study compared internal fixation and hemiarthroplasty in the treatment of unstable intertrochanteric fractures in the elderly. RevMan5.3 software provided by the International Cochrane Group was used for the meta-analysis. To compare the differences in the operation time, intraoperative bleeding, length of hospital stay, superficial infection, Harris hip score, mortality within 1 year, mortality within 2 years, reoperation, incidence of deep venous thrombosis (DVT), partial weight-bearing time, non-union, and implant-related complications between an internal fixation group and an hemiarthroplasty group. RESULTS: A total of 1300 patients were included in nine studies. The results showed that the operation time (MD = -18.09, 95% CI: -27.85--8.34, P = 0.0003), intraoperative bleeding (MD = -195.31, 95% CI: -244.8--147.74, P < 0.0001), implant-related complications (MD = 3.83, 95% CI: 1.74-8.45, P = 0.0008), and partial weight-bearing time (MD = 17.21, 95% CI: 1.63-32.79, P = 0.03) have statistical significance. However, there is not statistical significance for the Harris hip joint function scale (HHS) (MD = 5.60, 95% CI: -1.13-12.33, P = 0.10), DVT (MD = 1.02, 95% CI: 0.45-2.27, P = 0.97), length of hospital stay (MD = -1.08, 95% CI: -2.82-0.66, P = 0.22), superficial Infection (OR = 0.92, 95% CI: 0.43-1.98, P = 0.89), mortality within 1 year (OR = 0.95, 95% CI: 0.61-1.48, P = 0.81), mortality within 2 years (OR = 0.93, 95% CI: 0.61-1.43, P = 0.75), reoperation (MD = 1.80, 95% CI: 0.64-5.04, P = 0.26), and non-union (OR = 1.20, 95% CI: 0.48-3.03, P = 0.70). The result of the subgroup analysis showed no significant differences between the less than 2 years follow-up and the 2 years or more follow-up group. The only difference was for the Harris hip score: the internal fixation group was superior to the hemiarthroplasty group in the less than 2 years subgroup analysis, while there was no difference between the internal fixation group hemiarthroplasty group in the 2 years or more subgroup analysis. CONCLUSION: Compared with the internal fixation group, those in the hemiarthroplasty group could carry out weight-bearing training early and implant-related complications were reduced, but it requires longer operation time and there is greater intraoperative blood loss. There is no difference in mortality, the incidence of DVT, non-union, HHS, reoperation, length of hospital stay, and superficial infection. Hemiarthroplasty may be a better choice for unstable intertrochanteric fractures in the elderly.


Assuntos
Fixação Interna de Fraturas/métodos , Hemiartroplastia/métodos , Fraturas do Quadril/cirurgia , Idoso , Avaliação da Deficiência , Humanos , Complicações Pós-Operatórias , Resultado do Tratamento
13.
Orthop Surg ; 12(3): 1010-1015, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32307926

RESUMO

Congenital pain insensitivity is a rare genetic disease and its clinical manifestations are many. In orthopaedics, common complications of this disease include painless fracture and Charcot's arthropathy. We followed up a case of multiple fractures of the lower extremity in two years, during which time he came to the clinic for five painless fractures of the lower extremity in a total of six parts. A mutation was found on the NTKRI gene (chr1:156813923(hg19), NM_001007792.1: c.1221938C > T). We have developed a combination of surgery and conservative treatments for his condition, focusing on the mental state of the child and considering comprehensive treatment to be the best option for this type of patient. Occult fractures caused by pain insensitivity are often treated only as fractures, however their complications require routine examination and cleaning, suitable protective shoes, splint fixation, stretching, guided exercise planning, and early treatment of injuries. Due to the risk of fracture in the future, it is important that parents pay attention to the behavior and psychology of the child, such as not letting the child participate in exercise with a risk of injury, protective measures while playing, engaging in psychological counseling, and inducing interest in mental activity. These interventions will play a very important role in preventing the recurrence of fracture.


Assuntos
Fraturas Múltiplas/etiologia , Fraturas Múltiplas/cirurgia , Insensibilidade Congênita à Dor/complicações , Pré-Escolar , Tratamento Conservador , Humanos , Extremidade Inferior , Masculino
14.
Stem Cells Int ; 2020: 8811963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963548

RESUMO

Chondrogenesis and subsequent osteogenesis of mesenchymal stem cells (MSCs) and angiogenesis at injured sites are crucial for bone fracture healing. Amygdalin, a cyanogenic glycoside compound derived from bitter apricot kernel, has been reported to inhibit IL-1ß-induced chondrocyte degeneration and to stimulate blood circulation, suggesting a promising role of amygdalin in fracture healing. In this study, tibial fractures in C57BL/6 mice were treated with amygdalin. Fracture calluses were then harvested and subjected to radiographic, histological, and biomechanical testing, as well as angiography and gene expression analyses to evaluate fracture healing. The results showed that amygdalin treatment promoted bone fracture healing. Further experiments using MSC-specific transforming growth factor- (TGF-) ß receptor 2 conditional knockout (KO) mice (Tgfbr2Gli1-Cre ) and C3H10 T1/2 murine mesenchymal progenitor cells showed that this effect was mediated through TGF-ß/Smad signaling. We conclude that amygdalin could be used as an alternative treatment for bone fractures.

15.
ACS Appl Mater Interfaces ; 11(41): 37693-37700, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31532197

RESUMO

Na metal is a promising anode for Na batteries owing to its high theoretical capacity and low reduction potential. Nevertheless, an unstable and inhomogeneous solid electrolyte interphase originated from the instantaneous reactions between the Na metal anode and organic liquid electrolyte causes the intractable hurdles of dendrite growth and low Coulombic efficiency. Here, a sodium fluoride (NaF)-poly(vinylidene difluoride) (PVDF) inorganic-organic hybrid protective layer is constructed on a commercial Cu current collector via a simple blade-coating technique. A flexible PVDF matrix can endure volume change, maintaining the integrity of the anode/coating interface, while NaF particles provide improved Na+ diffusion conductivity and mechanical strength, suppressing the dendrite initiation and growth. Based on these synergetic effects, an excellent cycle life of more than ∼2100 h is realized at 1 mA cm-2 at 50% depth of discharge (DOD), which outperforms 10-fold lifetime of the Cu current collector (∼170 h). Moreover, the Cu current collector with a NaF-PVDF protective layer also delivers good cycling stability at 5 mA cm-2 and an ultrahigh DOD (80%). The rational design of the hybrid protective layer offers a new approach to realize stable Na metal batteries.

16.
Zhongguo Gu Shang ; 32(10): 975-978, 2019 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-32512974

RESUMO

Crowned dens syndrome(CDS) is a major imaging manifestation of "coronary" calcified deposits around the odontoid, with pain, stiffness, fever, and even cervical cord compression in the upper head and neck. It was first described by Bouvet et al. in 1985, and the onset was generally thought to be caused by crystal deposition. The clinical manifestations of CDS are often similar to meningitis and often accompanied by an increase in inflammatory markers in the blood. As a result, it is very easy to obtain missed diagnosis and misdiagnosis, and it is clinically prone to obtain wrong or unnecessary treatment. At present, the diagnosis of CDS is based on the imaging findings in CT as a "golden standard". NASIDs drugs and corticosteroids are the main treatment. The prognosis is also generally good, and the imaging findings of the patients with the disease disappear completely within 3 months.


Assuntos
Calcinose , Humanos , Cervicalgia , Processo Odontoide , Síndrome , Tomografia Computadorizada por Raios X
17.
ACS Appl Mater Interfaces ; 11(8): 8148-8154, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30707016

RESUMO

Intractable hurdles of low Coulombic efficiency and dendritic Li formation during a repeated deposition/stripping process hinder the commercial use of  Li metal anode for next-generation battery systems. Achieving uniform Li nucleation is one of the effective strategies to address these issues, and it is of practical importance to realize this on a commercial Cu current collector that is lithiophobic. Herein, we design a nanostructured Ag lithiophilic layer on a Cu foil via an electroless plating process for a Li metal current collector. The deposition of lithiophilic Ag particles that are homogeneously distributed on the Cu foil can reduce the nucleation overpotential, realizing uniform Li nucleation and subsequently flat Li plating. As a result, a stable cycle stability of up to 360 h (1 mA cm-2) and an average Columbic efficiency of 94.5% for 100 cycles (1 mA cm-2) are achieved. Furthermore, CuAg full cells with LiFePO4 as a cathode exhibit good cycle performances and low polarization voltage. This approach provides another facile way for a stable lithium metal anode.

18.
Chem Commun (Camb) ; 53(80): 11001-11004, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28905068

RESUMO

We report a mild synthetic method to access Sn nanocrystals with tunable diameter and narrow size distribution (6-8%). The self-templated formation of various types of Sn chalcogenide hollow nanostructures including oxides, sulfides, selenides, and tellurides is also demonstrated for the first time. The use of air-stable tungsten hexacarbonyl that produces carbon monoxide at elevated temperature to reduce the SnCl2 precursor and coordinate the nanoparticle surface is thought to play an essential role in this method. This synthesis method is likely to be extended to other metal systems and could find potential applications including battery anodes and catalysts.

19.
Adv Mater ; 28(41): 9223-9230, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27594204

RESUMO

A novel natural drying (ND) strategy for low-cost and simple fabrication of graphene aerogels (GAs) is highlighted. The as-formed NDGAs exhibit ultralarge reversible compressibility (99%) and tunable Poisson's ratio behaviors (-0.30 < ν < 0.46), which suggests promising applications in soft actuators, soft robots, sensors, deformable electronic devices, drug release, thermal insulator, and protective materials.

20.
Adv Mater ; 28(11): 2229-37, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26788692

RESUMO

A hyperbolically patterned 3D graphene metamaterial (GM) with negative Poisson's ratio and superelasticity is highlighted. It is synthesized by a modified hydrothermal approach and subsequent oriented freeze-casting strategy. GM presents a tunable Poisson's ratio by adjusting the structural porosity, macroscopic aspect ratio (L/D), and freeze-casting conditions. Such a GM suggests promising applications as soft actuators, sensors, robust shock absorbers, and environmental remediation.


Assuntos
Grafite/química , Elasticidade , Microscopia Eletrônica de Varredura , Distribuição de Poisson , Porosidade , Resistência à Tração , Difração de Raios X
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