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1.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(2): 293-298, 2024 Apr 18.
Artigo em Zh | MEDLINE | ID: mdl-38595247

RESUMO

OBJECTIVE: The pain-relieving effect and safety of compound aminopyrine phenacetin tablets, tramcontin (tramadol hydrochloride sustained-release tablets) and dolantin in the early stage of autologous tendon reconstruction of the anterior cruciate ligament (ACL) of the knee joint were compared. METHODS: Retrospective analysis of postoperative pain and drug analgesia in 45 patients performed by the same group from November 2018 to February 2019. The random area group design was divided into two groups according to whether ACL rupture was combined with meniscal injury, group A was 24 patients with ACL reconstruction of knee joint and group B was 21 patients with ACL fracture combined with meniscus injury. The two groups were divided into three subgroups respectively according to the actual treatment of postoperative analgesic drugs received by the patients, including 4 cases of compound aminopyrine phenacetin tablets, 11 cases of oral tramcontin, 9 cases of intramuscular dolantin combined with phenergan in group A; 3 cases of compound aminopyrine phenacetin tablets, 10 cases of oral tramcontin, and 8 cases of intramuscular dolantin combined with phenergan in group B. When the early postoperative patients complain about pain and actively ask for analgesia. When the patients complained about pain after the operation and actively asked for analgesia, they were randomly given painkillers, tramcontin or dolantin combined with phenergan to relieve pain. Pain visual analogue scale (VAS) was used to evaluate pain relief and observe the occurrence of adverse reactions. RESULTS: There were no significant dif-ferences in gender, age, body mass index, and time of hospital stay between the two groups of patients (P > 0.05). In the patients who used tramcontin and dolantin combined with phenergan to relieve pain judging by VAS score before and 1 h after taking the drug, it was found that the pain situation of the patient was significantly relieved, and the difference before and after taking the drug had statistical significance (P < 0.05). Pairwise comparisons of the three drugs applied in the two groups showed significantly greater pain relief in the dolantin combined with phenergan group than in the remaining two drugs. There was no significant difference (P > 0.05). Dolantin was prone to nausea and vomiting, but the application of phenergan was also used to reduce side effects. In terms of adverse reactions, only 1 case of nausea occurred in the tramcontin group for simple ACL reconstruction, and none of the patients in the other groups showed serious complications and allergic reactions. CONCLUSION: Whether in cruciate ligament reconstruction alone or combined with meniscus molding or suture, compound aminopyrine phenacetin tablets, tramcontin, dolantin combined with phenergan can effectively relieve pain. Among the three drugs, dolantin caused the largest pain relief. At the same time, the combination of phenergan effectively reduced the adverse reactions, such as vomiting and nausea, and increased the drug safety.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Aminopirina , Analgésicos , Lesões do Ligamento Cruzado Anterior/cirurgia , Articulação do Joelho/cirurgia , Meperidina , Náusea/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Fenacetina , Prometazina , Estudos Retrospectivos , Resultado do Tratamento , Vômito/cirurgia
2.
Nat Mater ; 21(3): 290-296, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34824395

RESUMO

Two-phase titanium-based alloys are widely used in aerospace and biomedical applications, and they are obtained through phase transformations between a low-temperature hexagonal closed-packed α-phase and a high-temperature body-centred cubic ß-phase. Understanding how a new phase evolves from its parent phase is critical to controlling the transforming microstructures and thus material properties. Here, we report time-resolved experimental evidence, at sub-ångström resolution, of a non-classically nucleated metastable phase that bridges the α-phase and the ß-phase, in a technologically important titanium-molybdenum alloy. We observed a nanosized and chemically ordered superstructure in the α-phase matrix; its composition, chemical order and crystal structure are all found to be different from both the parent and the product phases, but instigating a vanishingly low energy barrier for the transformation into the ß-phase. This latter phase transition can proceed instantly via vibrational switching when the molybdenum concentration in the superstructure exceeds a critical value. We expect that such a non-classical phase evolution mechanism is much more common than previously believed for solid-state transformations.


Assuntos
Ligas , Titânio , Ligas/química , Temperatura Alta , Molibdênio/química , Transição de Fase , Titânio/química
3.
Altern Ther Health Med ; 29(1): 111-117, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35951070

RESUMO

Context: Knee arthritis is the primary cause of disability in middle-aged and older adults. Total knee arthroplasty (TKA) is also a common treatment in clinics and has a remarkable effect on improving knee-joint function. However, TKA is an invasive procedure that includes a large amount of trauma. It can easily lead to an increase in perioperative blood loss coupled with a long operation time, which can increase the risk of postoperative complications, and also has a long recovery time. Objective: The study intended to analyze the value of tranexamic acid (TXA) plus progressive nursing in accelerating the postoperative rehabilitation of patients undergoing total knee arthroplasty (TKA). Design: The research team designed a prospective non-randomized controlled trial. Setting: The study took place at Cangzhou Hospital of Integrated Traditional Chinese Medicine (TCM) - Western Medicine (WM) Hebei in Cangzhou, Hebei, China. Participants: Participants were 115 patients with knee arthritis who underwent TKA at the hospital between February 2019 and October 2021. Intervention: Of the 115 participants, 55 were assigned to the control group and received conventional nursing care, and 60 were assigned to the intervention group and after surgery received TXA plus progressive nursing. Outcome Measures: The study measured blood loss postoperatively and identified any complications that participants experienced during treatment. At baseline and postintervention, the study also measured knee-joint range of motion (ROM), and the participants completed the Hospital for Special Surgery (HSS) knee survey, the Barthel Index for Activities of Daily Living (ADL), the Self-Rating Depression (SDS) and Self-Rating Anxiety (SAS) scales, a nursing-satisfaction survey, and the World Health Organization Quality of Life Bref (WHO-QOL-BREF) survey. Results: Postoperatively, the blood loss in the intervention group was significantly lower than that in control group, and the knee joint ROM was significantly better in the intervention group (P < .05). In addition, the postoperative Hospital for Special Surgery (HSS) and Barthel scores in the intervention group were significantly higher, and the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores were significantly lower in the intervention group compared with control group (P < .05). Moreover, a lower incidence of complications and better quality of life were determined for the intervention group (P < .05). Conclusions: Compared with conventional nursing, TXA plus progressive nursing can more effectively promote postoperative recovery of TKA patients; but the exact role of TXA and progressive nursing in TKA deserves further exploration.


Assuntos
Antifibrinolíticos , Artrite , Artroplastia do Joelho , Ácido Tranexâmico , Pessoa de Meia-Idade , Humanos , Idoso , Ácido Tranexâmico/uso terapêutico , Artroplastia do Joelho/métodos , Qualidade de Vida , Antifibrinolíticos/uso terapêutico , Perda Sanguínea Cirúrgica , Atividades Cotidianas , Estudos Prospectivos
4.
Pak J Pharm Sci ; 36(3(Special)): 921-925, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37587699

RESUMO

To investigate the effects of glucosamine hydrochloride combined with non-steroidal anti-inflammatory drugs on symptoms and HSS scores in patients with knee osteoarthritis (KOA). Totally 80 cases of patients with KOA admitted to Cangzhou Hospital of integrated TCM-WM from February 2016 to December 2019 were selected and divided into the Control Group and Observation Group by Random Number Table Method, with 40 cases in each group. After treatment, the Observation Group tends to have lower VAS scores and WOMAC scores than the Control Group (P<0.05). The Observation Group tends to perform better than the Control Group on symptom improvement rate and HSS scores (P<0.05). The expression levels of related inflammatory factors and matrix metalloproteinase (MMPs) are similar before and after treatment in the Control Group (P>0.05). The expression levels of related inflammatory factors and MMPs get lower after treatment in the Observation Group (P<0.05). The evaluation indexes and total scores of the Observation Group are better than those of the Control Group (P<0.05). Glucosamine hydrochloride combined with non-steroidal anti-inflammatory drugs treatment could decrease the expression levels of inflammatory cytokines, relieve knee pain and arthritis symptoms, improve knee function and improve the HSS scores in patients with KOA.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Glucosamina/uso terapêutico , Articulação do Joelho , Anti-Inflamatórios não Esteroides/uso terapêutico , Citocinas
5.
Pak J Pharm Sci ; 36(4(Special)): 1337-1341, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37606025

RESUMO

To investigate the effects of glucosamine hydrochloride combined with non-steroidal anti-inflammatory drugs on symptoms and HSS scores in patients with knee osteoarthritis (KOA). Totally 80 cases of patients with KOA admitted to Cangzhou Hospital of integrated TCM-WM from February 2016 to December 2019 were selected and divided into the Control Group and Observation Group by Random Number Table Method, with 40 cases in each group. After treatment, the Observation Group tends to have lower VAS scores and WOMAC scores than the Control Group (P<0.05). The Observation Group tends to perform better than the Control Group on symptom improvement rate and HSS scores (P<0.05). The expression levels of related inflammatory factors and matrix metalloproteinase (MMPs) are similar before and after treatment in the Control Group (P>0.05). The expression levels of related inflammatory factors and MMPs get lower after treatment in the Observation Group (P<0.05). The evaluation indexes and total scores of the Observation Group are better than those of the Control Group (P<0.05). Glucosamine hydrochloride combined with non-steroidal anti-inflammatory drugs treatment could decrease the expression levels of inflammatory cytokines, relieve knee pain and arthritis symptoms, improve knee function and improve the HSS scores in patients with KOA.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/tratamento farmacológico , Glucosamina/uso terapêutico , Articulação do Joelho , Anti-Inflamatórios não Esteroides/uso terapêutico , Citocinas
6.
Small ; 18(21): e2201753, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35491494

RESUMO

Chalcogenides such as GeTe, PbTe, Sb2 Te3 , and Bi2 Se3 are characterized by an unconventional combination of properties enabling a plethora of applications ranging from thermo-electrics to phase change materials, topological insulators, and photonic switches. Chalcogenides possess pronounced optical absorption, relatively low effective masses, reasonably high electron mobilities, soft bonds, large bond polarizabilities, and low thermal conductivities. These remarkable characteristics are linked to an unconventional bonding mechanism characterized by a competition between electron delocalization and electron localization. Confinement, that is, the reduction of the sample dimension as realized in thin films should alter this competition and modify chemical bonds and the resulting properties. Here, pronounced changes of optical and vibrational properties are demonstrated for crystalline films of GeTe, while amorphous films of GeTe show no similar thickness dependence. For crystalline films, this thickness dependence persists up to remarkably large thicknesses above 15 nm. X-ray diffraction and accompanying simulations employing density functional theory relate these changes to thickness dependent structural (Peierls) distortions, due to an increased electron localization between adjacent atoms upon reducing the film thickness. A thickness dependence and hence potential to modify film properties for all chalcogenide films with a similar bonding mechanism is expected.

7.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(4): 417-422, 2023 Apr 15.
Artigo em Zh | MEDLINE | ID: mdl-37070307

RESUMO

Objective: To validate the effectiveness of a novel comprehensive classification for intertrochanteric fracture (ITF). Methods: The study included 616 patients with ITF, including 279 males (45.29%) and 337 females (54.71%); the age ranged from 23 to 100 years, with an average of 72.5 years. Two orthopaedic residents (observers Ⅰ and Ⅱ) and two senior orthopaedic surgeons (observers Ⅲ and Ⅳ) were selected to classify the CT imaging data of 616 patients in a random order by using the AO/Orthopaedic Trauma Association (AO/OTA) classification of 1996/2007 edition, the AO/OTA classification of 2018 edition, and the novel comprehensive classification method at an interval of 1 month. Kappa consistency test was used to evaluate the intra-observer and inter-observer consistency of the three ITF classification systems. Results: The inter-observer consistency of the three classification systems evaluated by 4 observers twice showed that the 3 classification systems had strong inter-observer consistency. Among them, the κ value of the novel comprehensive classification was higher than that of the AO/OTA classification of 1996/2007 edition and 2018 edition, and the experience of observers had a certain impact on the classification results, and the inter-observer consistency of orthopaedic residents was slightly better than that of senior orthopaedic surgeons. The intra-observer consistency of two evaluations of three classification systems by 4 observers showed that the consistency of the novel comprehensive classification was better for the other 3 observers, except that the consistency of observer Ⅳ in the AO/OTA classification of 2018 version was slightly higher than that of the novel comprehensive classification. The results showed that the novel comprehensive classification has higher repeatability, and the intra-observer consistency of senior orthopaedic surgeons was better than that of orthopaedic residents. Conclusion: The novel comprehensive classification system has good intra- and inter-observer consistency, and has high validity in the classification of CT images of ITF patients; the experience of observers has a certain impact on the results of the three classification systems, and those with more experiences have higher intra-observer consistency.


Assuntos
Fraturas do Quadril , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Tomografia Computadorizada por Raios X/métodos , Radiografia
8.
Adv Sci (Weinh) ; 10(23): e2302444, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37279377

RESUMO

The layered crystal structure of Cr2 Ge2 Te6 shows ferromagnetic ordering at the two-dimensional limit, which holds promise for spintronic applications. However, external voltage pulses can trigger amorphization of the material in nanoscale electronic devices, and it is unclear whether the loss of structural ordering leads to a change in magnetic properties. Here, it is demonstrated that Cr2 Ge2 Te6 preserves the spin-polarized nature in the amorphous phase, but undergoes a magnetic transition to a spin glass state below 20 K. Quantum-mechanical computations reveal the microscopic origin of this transition in spin configuration: it is due to strong distortions of the CrTeCr bonds, connecting chromium-centered octahedra, and to the overall increase in disorder upon amorphization. The tunable magnetic properties of Cr2 Ge2 Te6 can be exploited for multifunctional, magnetic phase-change devices that switch between crystalline and amorphous states.

9.
Adv Sci (Weinh) ; 10(15): e2300901, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36995041

RESUMO

Metavalent bonding (MVB) is characterized by the competition between electron delocalization as in metallic bonding and electron localization as in covalent or ionic bonding, serving as an essential ingredient in phase-change materials for advanced memory applications. The crystalline phase-change materials exhibits MVB, which stems from the highly aligned p orbitals and results in large dielectric constants. Breaking the alignment of these chemical bonds leads to a drastic reduction in dielectric constants. In this work, it is clarified how MVB develops across the so-called van der Waals-like gaps in layered Sb2 Te3 and Ge-Sb-Te alloys, where coupling of p orbitals is significantly reduced. A type of extended defect involving such gaps in thin films of trigonal Sb2 Te3 is identified by atomic imaging experiments and ab initio simulations. It is shown that this defect has an impact on the structural and optical properties, which is consistent with the presence of non-negligible electron sharing in the gaps. Furthermore, the degree of MVB across the gaps is tailored by applying uniaxial strain, which results in a large variation of dielectric function and reflectivity in the trigonal phase. At last, design strategies are provided for applications utilizing the trigonal phase.

10.
J Gerontol A Biol Sci Med Sci ; 77(11): 2288-2297, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-35417546

RESUMO

BACKGROUND: Klemera-Doubal's method (KDM) is an advanced and widely applied algorithm for estimating biological age (BA), but it has no uniform paradigm for biomarker processing. This article proposed all subsets of biomarkers for estimating BAs and assessed their association with mortality to determine the most predictive subset and BA. METHODS: Clinical biomarkers, including those from physical examinations and blood assays, were assessed in the China Health and Nutrition Survey (CHNS) 2009 wave. Those correlated with chronological age (CA) were combined to produce complete subsets, and BA was estimated by KDM from each subset of biomarkers. A Cox proportional hazards regression model was used to examine and compare each BA's effect size and predictive capacity for all-cause mortality. Validation analysis was performed in the Chinese Longitudinal Healthy Longevity Survey (CLHLS) and National Health and Nutrition Examination Survey (NHANES). KD-BA and Levine's BA were compared in all cohorts. RESULTS: A total of 130 918 panels of BAs were estimated from complete subsets comprising 3-17 biomarkers, whose Pearson coefficients with CA varied from 0.39 to 1. The most predictive subset consisted of 5 biomarkers, whose estimated KD-BA had the most predictive accuracy for all-cause mortality. Compared with Levine's BA, the accuracy of the best-fitting KD-BA in predicting death varied among specific populations. CONCLUSION: All-subset analysis could effectively reduce the number of redundant biomarkers and significantly improve the accuracy of KD-BA in predicting all-cause mortality.


Assuntos
Longevidade , Inquéritos Nutricionais , Biomarcadores , Modelos de Riscos Proporcionais
11.
Adv Sci (Weinh) ; 9(8): e2103478, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35032111

RESUMO

Phase-change material (PCM) devices are one of the most mature nonvolatile memories. However, their high power consumption remains a bottleneck problem limiting the data storage density. One may drastically reduce the programming power by patterning the PCM volume down to nanometer scale, but that route incurs a stiff penalty from the tremendous cost associated with the complex nanofabrication protocols required. Instead, here a materials solution to resolve this dilemma is offered. The authors work with memory cells of conventional dimensions, but design/exploit a PCM alloy that decomposes into a heterogeneous network of nanoscale crystalline domains intermixed with amorphous ones. The idea is to confine the subsequent phase-change switching in the interface region of the crystalline nanodomain with its amorphous surrounding, forming/breaking "nano-bridges" that link up the crystalline domains into a conductive path. This conductive-bridge switching mechanism thus only involves nanometer-scale volume in programming, despite of the large areas in contact with the electrodes. The pore-like devices based on spontaneously phase-separated Ge13 Sb71 O16 alloy enable a record-low programming energy, down to a few tens of femtojoule. The new PCM/fabrication is fully compatible with the current 3D integration technology, adding no expenses or difficulty in processing.

12.
Adv Sci (Weinh) ; 9(30): e2203776, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35981888

RESUMO

While metals can be readily processed and reshaped by cold rolling, most bulk inorganic semiconductors are brittle materials that tend to fracture when plastically deformed. Manufacturing thin sheets and foils of inorganic semiconductors is therefore a bottleneck problem, severely restricting their use in flexible electronic applications. It is recently reported that a few single-crystalline 2D van der Waals (vdW) semiconductors, such as InSe, are deformable under compressive stress. Here it is demonstrated that intralayer fracture toughness can be tailored via compositional design to make inorganic semiconductors processable by cold rolling. Systematic ab initio calculations covering a range of van der Waals semiconductors homologous to InSe are reported, leading to material-property maps that forecast trends in both the susceptibility to interlayer slip and the intralayer fracture toughness against cracking. GaSe is predicted, and experimentally confirmed, to be practically amenable to being rolled to large (three quarters) thickness reduction and length extension by a factor of three. The fracture toughness and cleavage energy are predicted to be 0.25 MPa m0.5 and 15 meV Å-2 , respectively. The findings open a new realm of possibility for alloy selection and design toward processing-friendly group-III chalcogenides for practical applications.

13.
Nat Commun ; 13(1): 7352, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446781

RESUMO

In glasses, secondary (ß-) relaxations are the predominant source of atomic dynamics. Recently, they have been discovered in covalently bonded glasses, i.e., amorphous phase-change materials (PCMs). However, it is unclear what the mechanism of ß-relaxations is in covalent systems and how they are related to crystallization behaviors of PCMs that are crucial properties for non-volatile memories and neuromorphic applications. Here we show direct evidence that crystallization is strongly linked to ß-relaxations. We find that the ß-relaxation in Ge15Sb85 possesses a high tunability, which enables a manipulation of crystallization kinetics by an order of magnitude. In-situ synchrotron X-ray scattering, dielectric functions, and ab-initio calculations indicate that the weakened ß-relaxation intensity stems from a local reinforcement of Peierls-like distortions, which increases the rigidity of the bonding network and decreases the dynamic heterogeneity. Our findings offer a conceptually new approach to tuning the crystallization of PCMs based on manipulating the ß-relaxations.

14.
Adv Mater ; 33(9): e2006221, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33491816

RESUMO

Tailoring the degree of disorder in chalcogenide phase-change materials (PCMs) plays an essential role in nonvolatile memory devices and neuro-inspired computing. Upon rapid crystallization from the amorphous phase, the flagship Ge-Sb-Te PCMs form metastable rocksalt-like structures with an unconventionally high concentration of vacancies, which results in disordered crystals exhibiting Anderson-insulating transport behavior. Here, ab initio simulations and transport experiments are combined to extend these concepts to the parent compound of Ge-Sb-Te alloys, viz., binary Sb2 Te3 , in the metastable rocksalt-type modification. Then a systematic computational screening over a wide range of homologous, binary and ternary chalcogenides, elucidating the critical factors that affect the stability of the rocksalt structure is carried out. The findings vastly expand the family of disorder-controlled main-group chalcogenides toward many more compositions with a tunable bandgap size for demanding phase-change applications, as well as a varying strength of spin-orbit interaction for the exploration of potential topological Anderson insulators.

15.
ACS Nano ; 14(4): 4456-4462, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32275386

RESUMO

Materials with layered crystal structures and high in-plane anisotropy, such as black phosphorus, present unique properties and thus promise for applications in electronic and photonic devices. Recently, the layered structures of GeS2 and GeSe2 were utilized for high-performance polarization-sensitive photodetection in the short wavelength region due to their high in-plane optical anisotropy and wide band gap. The highly complex, low-symmetric (monoclinic) crystal structures are at the origin of the high in-plane optical anisotropy, but the structural nature of the corresponding nanostructures remains to be fully understood. Here, we present an atomic-scale characterization of monoclinic GeS2 nanostructures and quantify the in-plane structural anisotropy at the sub-angstrom level in real space by Cs-corrected scanning transmission electron microscopy. We elucidate the origin of this high in-plane anisotropy in terms of ordered and disordered arrangement of [GeS4] tetrahedra in GeS2 monolayers, through density functional theory (DFT) calculations and orbital-based bonding analyses. We also demonstrate high in-plane mechanical, electronic, and optical anisotropies in monolayer GeS2 and envision phase transitions under uniaxial strain that could potentially be exploited for nonvolatile memory applications.

16.
Science ; 366(6462): 210-215, 2019 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-31439757

RESUMO

Artificial intelligence and other data-intensive applications have escalated the demand for data storage and processing. New computing devices, such as phase-change random access memory (PCRAM)-based neuro-inspired devices, are promising options for breaking the von Neumann barrier by unifying storage with computing in memory cells. However, current PCRAM devices have considerable noise and drift in electrical resistance that erodes the precision and consistency of these devices. We designed a phase-change heterostructure (PCH) that consists of alternately stacked phase-change and confinement nanolayers to suppress the noise and drift, allowing reliable iterative RESET and cumulative SET operations for high-performance neuro-inspired computing. Our PCH architecture is amenable to industrial production as an intrinsic materials solution, without complex manufacturing procedure or much increased fabrication cost.

17.
Exp Ther Med ; 15(5): 4503-4507, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725385

RESUMO

Synovial chondromatosis, also known as synovial osteochondromatosis, is a rare, benign condition characterized by the formation of multiple cartilaginous nodules in the synovium of facet spaces. Synovial chondromatosis affects many joints, the knee being the most common. The present report examined a 47-year-old male with symptoms of swelling and pain in the right knee, who was admitted to hospital in September 2015. Following admittance, arthroscopic explorations were conducted. Viscous fluid and multiple cartilage-like clumps were identified in the patient's joints during surgery. There was evidence of synovial hyperemia and edema in the inner and outer lateral recesses of the patellar bursa, accompanied by villous projections. Synovium debridement and removal of cartilage-like free masses were performed. Following 6-month follow-up, the motion of the right knee ranged from 0-150° and no further swelling or pain was experienced by the patient. Following arthroscopy, the international knee documentation committee function score improved from 70.6 to 89.4 points. The results of the present report indicate that arthroscopic exploration is an effective treatment for patients with synovial chondromatosis.

18.
Nanoscale ; 10(16): 7363-7368, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29637969

RESUMO

The recently discovered two-dimensional (2D) group IV chalcogenides attract much attention owing to their novel electronic and photonic properties. All the reported materials of this class favor (distorted) octahedral coordination via p bonding; by contrast, in the dichalcogenides where the bonding tendency approaches sp3, no corresponding 2D phase has been realized so far. Here, by engineering the composition of a chalcogenide heterostructure, the hitherto elusive GeTe2 is experimentally observed in a confined 2D environment. Density functional theory simulations predict the existence of a freestanding monolayer of octahedrally coordinated GeTe2 under tensile strain, and the existence of GeSe2 and GeS2 in the same form under equilibrium conditions. These 2D germanium dichalcogenides are either metallic or narrow gap semiconducting, and may lead to new applications in nanoscale electronics.

19.
Materials (Basel) ; 10(8)2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28773222

RESUMO

Metal-insulator transition (MIT) is one of the most essential topics in condensed matter physics and materials science. The accompanied drastic change in electrical resistance can be exploited in electronic devices, such as data storage and memory technology. It is generally accepted that the underlying mechanism of most MITs is an interplay of electron correlation effects (Mott type) and disorder effects (Anderson type), and to disentangle the two effects is difficult. Recent progress on the crystalline Ge1Sb2Te4 (GST) compound provides compelling evidence for a disorder-driven MIT. In this work, we discuss the presence of strong disorder in GST, and elucidate its effects on electron localization and transport properties. We also show how the degree of disorder in GST can be reduced via thermal annealing, triggering a disorder-driven metal-insulator transition. The resistance switching by disorder tuning in crystalline GST may enable novel multilevel data storage devices.

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