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1.
Nat Commun ; 11(1): 2390, 2020 May 13.
Article in English | MEDLINE | ID: mdl-32404913

ABSTRACT

Alloys with ultra-high strength and sufficient ductility are highly desired for modern engineering applications but difficult to develop. Here we report that, by a careful controlling alloy composition, thermomechanical process, and microstructural feature, a Co-Cr-Ni-based medium-entropy alloy (MEA) with a dual heterogeneous structure of both matrix and precipitates can be designed to provide an ultra-high tensile strength of 2.2 GPa and uniform elongation of 13% at ambient temperature, properties that are much improved over their counterparts without the heterogeneous structure. Electron microscopy characterizations reveal that the dual heterogeneous structures are composed of a heterogeneous matrix with both coarse grains (10∼30 µm) and ultra-fine grains (0.5∼2 µm), together with heterogeneous L12-structured nanoprecipitates ranging from several to hundreds of nanometers. The heterogeneous L12 nanoprecipitates are fully coherent with the matrix, minimizing the elastic misfit strain of interfaces, relieving the stress concentration during deformation, and playing an active role in enhanced ductility.

2.
Nature ; 563(7731): 374-378, 2018 11.
Article in English | MEDLINE | ID: mdl-30429543

ABSTRACT

High-temperature copper oxide superconductors consist of stacked CuO2 planes, with electronic band structures and magnetic excitations that are primarily two-dimensional1,2, but with superconducting coherence that is three-dimensional. This dichotomy highlights the importance of out-of-plane charge dynamics, which has been found to be incoherent in the normal state3,4 within the limited range of momenta accessible by optics. Here we use resonant inelastic X-ray scattering to explore the charge dynamics across all three dimensions of the Brillouin zone. Polarization analysis of recently discovered collective excitations (modes) in electron-doped copper oxides5-7 reveals their charge origin, that is, without mixing with magnetic components5-7. The excitations disperse along both the in-plane and out-of-plane directions, revealing its three-dimensional nature. The periodicity of the out-of-plane dispersion corresponds to the distance between neighbouring CuO2 planes rather than to the crystallographic c-axis lattice constant, suggesting that the interplane Coulomb interaction is responsible for the coherent out-of-plane charge dynamics. The observed properties are hallmarks of the long-sought 'acoustic plasmon', which is a branch of distinct charge collective modes predicted for layered systems8-12 and argued to play a substantial part in mediating high-temperature superconductivity10-12.

3.
Fa Yi Xue Za Zhi ; 33(3): 284-288, 2017 Jun.
Article in Chinese | MEDLINE | ID: mdl-29230996

ABSTRACT

Due to the negative autopsy and without cardiac structural abnormalities, unexpected sudden cardiac death (USCD) is always a tough issue for forensic pathological expertise. USCD may be associated with parts of fatal arrhythmic diseases. These arrhythmic diseases may be caused by disorders of cardiac ion channels or channel-related proteins. Caveolin can combine with multiple myocardial ion channel proteins through its scaffolding regions and plays an important role in maintaining the depolarization and repolarization of cardiac action potential. When the structure and function of caveolin are affected by gene mutations or abnormal protein expression, the functions of the regulated ion channels are correspondingly impaired, which leads to the occurrence of multiple channelopathies, arrhythmia or even sudden cardiac death. It is important to study the effects of caveolin on the functions of ion channels for exploring the mechanisms of malignant arrhythmia and sudden cardiac death.


Subject(s)
Arrhythmias, Cardiac/physiopathology , Caveolins/metabolism , Channelopathies/genetics , Ion Channels/metabolism , Arrhythmias, Cardiac/genetics , Arrhythmias, Cardiac/metabolism , Autopsy , Channelopathies/complications , Death, Sudden, Cardiac/etiology , Death, Sudden, Cardiac/pathology , Forensic Pathology , Humans , Ion Channels/genetics , Mutation , Myocardium
4.
Fa Yi Xue Za Zhi ; 33(2): 114-119, 2017 Apr.
Article in Chinese | MEDLINE | ID: mdl-29231014

ABSTRACT

OBJECTIVES: To explore the genetic variation sites of caveolin (CAV) and their correlation with sudden unexplained death (SUD). METHODS: The blood samples were collected from SUD group (71 cases), coronary artery disease (CAD) group (62 cases) and control group (60 cases), respectively. The genome DNA were extracted and sequencing was performed directly by amplifying gene coding region and exon-intron splicing region of CAV1 and CAV3 using PCR. The type of heritable variation of CVA was confirmed and statistical analysis was performed. RESULTS: A total of 4 variation sites that maybe significative were identified in SUD group, and two were newfound which were CAV1: c.45C>T (T15T) and CAV1:c.512G>A (R171H), and two were SNP loci which were CAV1:c.246C>T (rs35242077) and CAV3:c.99C>T (rs1008642) and had significant difference (P<0.05) in allele and genotype frequencies between SUD and control groups. Forementioned variation sites were not found in CAD group. CONCLUSIONS: The variants of CAV1 and CAV3 may be correlated with a part of SUD group.


Subject(s)
Caveolins/genetics , Death, Sudden/etiology , Polymorphism, Single Nucleotide , Coronary Artery Disease , Exons , Genotype , Humans , Male , Polymerase Chain Reaction
5.
Ann Oncol ; 20(2): 343-8, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18765460

ABSTRACT

BACKGROUND: Quality of end-of-life care received by cancer patients has never been explored in an entire Asian country for all ages and cancer groups. PATIENTS AND METHODS: Retrospective cohort study to examine trends in quality of end-of-life care among a cohort of 242 530 Taiwanese cancer patients who died in 2000-2006. RESULTS: In the last month of life, cancer care tended to become increasingly aggressive as shown by (i) intensive use of chemotherapy (15.45%-17.28%), (ii) frequent emergency room visits (15.69%-20.99%) and >14-day hospital stays (41.48%-46.20%), (iii) admissions to intensive care units (10.04%-12.41%), and (iv) hospital deaths (59.11%-65.40%). Use of cardiopulmonary resuscitation (13.09%-8.41%), intubation (26.01%-21.07%), and mechanical ventilation (27.46%-27.05%) decreased, whereas use of hospice services increased considerably (7.34%-16.83%). Among those receiving hospice services, rates of referrals to hospice services in the last 3 days of life decreased from 17.88% to 17.13% but remained steady after adjusting for selected covariates. CONCLUSIONS: The quality of end-of-life care for Taiwanese cancer decedents was substantially inferior to that previously reported and to that recommended as benchmarks for not providing overly aggressive care near the end of life.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hospice Care/trends , Neoplasms/drug therapy , Palliative Care/trends , Terminal Care/trends , Aged , Aged, 80 and over , Cohort Studies , Databases, Factual , Emergency Service, Hospital/trends , Female , Hospices/trends , Humans , Intensive Care Units/trends , Male , Middle Aged , Patient Admission/trends , Referral and Consultation/trends , Registries , Retrospective Studies , Taiwan
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