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1.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Article in English | MEDLINE | ID: mdl-33619099

ABSTRACT

Natural aerosols in pristine regions form the baseline used to evaluate the impact of anthropogenic aerosols on climate. Sea spray aerosol (SSA) is a major component of natural aerosols. Despite its importance, the abundance of SSA is poorly constrained. It is generally accepted that wind-driven wave breaking is the principle governing SSA production. This mechanism alone, however, is insufficient to explain the variability of SSA concentration at given wind speed. The role of other parameters, such as sea surface temperature (SST), remains controversial. Here, we show that higher SST promotes SSA mass generation at a wide range of wind speed levels over the remote Pacific and Atlantic Oceans, in addition to demonstrating the wind-driven SSA production mechanism. The results are from a global scale dataset of airborne SSA measurements at 150 to 200 m above the ocean surface during the NASA Atmospheric Tomography Mission. Statistical analysis suggests that accounting for SST greatly enhances the predictability of the observed SSA concentration compared to using wind speed alone. Our results support implementing SST into SSA source functions in global models to better understand the atmospheric burdens of SSA.

2.
Phys Rev Lett ; 130(19): 196401, 2023 May 12.
Article in English | MEDLINE | ID: mdl-37243643

ABSTRACT

We present the first experimental evidence of a topological phase transition in a monoelemental quantum spin Hall insulator. Particularly, we show that low-buckled epitaxial germanene is a quantum spin Hall insulator with a large bulk gap and robust metallic edges. Applying a critical perpendicular electric field closes the topological gap and makes germanene a Dirac semimetal. Increasing the electric field further results in the opening of a trivial gap and disappearance of the metallic edge states. This electric field-induced switching of the topological state and the sizable gap make germanene suitable for room-temperature topological field-effect transistors, which could revolutionize low-energy electronics.

3.
Zhongguo Zhong Yao Za Zhi ; 48(18): 4902-4907, 2023 Sep.
Article in Zh | MEDLINE | ID: mdl-37802832

ABSTRACT

Malaria, one of the major global public health events, is a leading cause of mortality and morbidity among children and adults in tropical and subtropical regions(mainly in sub-Saharan Africa), threatening human health. It is well known that malaria can cause various complications including anemia, blackwater fever, cerebral malaria, and kidney damage. Conventionally, cardiac involvement has not been listed as a common reason affecting morbidity and mortality of malaria, which may be related to ignored cases or insufficient diagnosis. However, the serious clinical consequences such as acute coronary syndrome, heart failure, and malignant arrhythmia caused by malaria have aroused great concern. At present, antimalarials are commonly used for treating malaria in clinical practice. However, inappropriate medication can increase the risk of cardiovascular diseases and cause severe consequences. This review summarized the research advances in the cardiovascular complications including acute myocardial infarction, arrhythmia, hypertension, heart failure, and myocarditis in malaria. The possible mechanisms of cardiovascular diseases caused by malaria were systematically expounded from the hypotheses of cell adhesion, inflammation and cytokines, myocardial apoptosis induced by plasmodium toxin, cardiac injury secondary to acute renal failure, and thrombosis. Furthermore, the effects of quinolines, nucleoprotein synthesis inhibitors, and artemisinin and its derivatives on cardiac structure and function were summarized. Compared with the cardiac toxicity of quinolines in antimalarial therapy, the adverse effects of artemisinin-derived drugs on heart have not been reported in clinical studies. More importantly, the artemisinin-derived drugs demonstrate favorable application prospects in the prevention and treatment of cardiovascular diseases, and are expected to play a role in the treatment of malaria patients with cardiovascular diseases. This review provides reference for the prevention and treatment of malaria-related cardiovascular complications as well as the safe application of antimalarials.


Subject(s)
Antimalarials , Artemisinins , Cardiovascular Diseases , Heart Failure , Malaria, Cerebral , Quinolines , Child , Adult , Humans , Antimalarials/pharmacology , Cardiovascular Diseases/drug therapy , Artemisinins/pharmacology , Malaria, Cerebral/drug therapy , Heart Failure/drug therapy , Arrhythmias, Cardiac/drug therapy
4.
Popul Health Metr ; 20(1): 19, 2022 10 07.
Article in English | MEDLINE | ID: mdl-36207752

ABSTRACT

BACKGROUND: Most cancer disability-adjusted life year (DALY) studies worldwide have used broad, generic disability weights (DWs); however, differences exist among populations and types of cancers. Using breast cancer as example, this study aimed to estimate the population-level DALYs in females in China and the impact of screening as well as applying local DWs. METHODS: Using multisource data, a prevalence-based model was constructed. (1) Overall years lived with disability (YLDs) were estimated by using numbers of prevalence cases, stage-specific proportions, and local DWs for breast cancer. Numbers of females and new breast cancer cases as well as local survival rates were used to calculate the number of prevalence cases. (2) Years of life lost (YLLs) were estimated using breast cancer mortality rates, female numbers and standard life expectancies. (3) The prevalence of and mortality due to breast cancer and associated DALYs from 2020 to 2030 were predicted using Joinpoint regression. (4) Assumptions considered for screening predictions included expanding coverage, reducing mortality due to breast cancer and improving early-stage proportion for breast cancer. RESULTS: In Chinese females, the estimated number of breast cancer DALYs was 2251.5 thousand (of 17.3% were YLDs) in 2015, which is predicted to increase by 26.7% (60.3% among those aged ≥ 65 years) in 2030 (2852.8 thousand) if the screening coverage (25.7%) stays unchanged. However, if the coverage can be achieved to 40.7% in 2030 (deduced from the "Healthy China Initiative"), DALYs would decrease by 1.5% among the screened age groups. Sensitivity analyses found that using local DWs would change the base-case values by ~ 10%. CONCLUSION: Estimates of DALYs due to breast cancer in China were lower (with a higher proportion of YLDs) than Global Burden of Disease Study numbers (2527.0 thousand, 8.2% were YLDs), suggesting the importance of the application of population-specific DWs. If the screening coverage remains unchanged, breast cancer-caused DALYs would continue to increase, especially among elderly individuals.


Subject(s)
Breast Neoplasms , Aged , Breast Neoplasms/epidemiology , China/epidemiology , Disability-Adjusted Life Years , Early Detection of Cancer , Female , Global Burden of Disease , Humans , Prevalence , Quality-Adjusted Life Years
5.
Cost Eff Resour Alloc ; 20(1): 36, 2022 Jul 23.
Article in English | MEDLINE | ID: mdl-35870941

ABSTRACT

BACKGROUND: Benchmark data on the population-level economic burden are critical to inform policymakers about liver cancer control. However, comprehensive data in China are currently limited. METHODS: A prevalence-based approach from a societal perspective was used to quantify the annual economic burden of liver cancer in China from 2019 to 2030. Detailed per-case data on medical/non-medical expenditure and work-loss days were extracted from a multicenter survey. The numbers/rates of new/prevalent cases and deaths, survival, and population-related parameters were extracted from the Global Burden of Disease 2019 and the literature. All expenditure data were reported in both 2019 Chinese Yuan (CNY) and United States dollar (US$, for main estimations). RESULT: The overall economic burden of liver cancer was estimated at CNY76.7/US$11.1 billion in China in 2019 (0.047% of the local GDP). The direct expenditure was CNY21.6/US$3.1 billion, including CNY19.7/US$2.9 billion for medical expenditure and CNY1.9/US$0.3 billion for non-medical expenditure. The indirect cost was CNY55.1/US$8.0 billion (71.8% of the overall burden), including CNY3.0/US$0.4 billion due to disability and CNY52.0/US$7.5 billion due to premature death. The total burden would increase to CNY84.2/US$12.2 billion, CNY141.7/US$20.5 billion, and CNY234.3/US$34.0 billion in 2020, 2025, and 2030, accounting for 0.102%, 0.138%, and 0.192% of China's GDP, respectively. However, if China achieves the goals of Healthy China 2030 or the United Nations' Sustainable Development Goals for non-communicable diseases, the burden in 2030 would be < CNY144.4/US$20.9 billion. CONCLUSIONS: The population-level economic burden of liver cancer in China is currently substantial and will consistently increase in the future. Sustainable efforts in primary and secondary interventions for liver cancer need to be further strengthened.

6.
Proc Natl Acad Sci U S A ; 116(36): 17696-17700, 2019 Sep 03.
Article in English | MEDLINE | ID: mdl-31420513

ABSTRACT

Great progress has been achieved in the research field of topological states of matter during the past decade. Recently, a quasi-1-dimensional bismuth bromide, Bi4Br4, has been predicted to be a rotational symmetry-protected topological crystalline insulator; it would also exhibit more exotic topological properties under pressure. Here, we report a thorough study of phase transitions and superconductivity in a quasihydrostatically pressurized α-Bi4Br4 crystal by performing detailed measurements of electrical resistance, alternating current magnetic susceptibility, and in situ high-pressure single-crystal X-ray diffraction together with first principles calculations. We find a pressure-induced insulator-metal transition between ∼3.0 and 3.8 GPa where valence and conduction bands cross the Fermi level to form a set of small pockets of holes and electrons. With further increase of pressure, 2 superconductive transitions emerge. One shows a sharp resistance drop to 0 near 6.8 K at 3.8 GPa; the transition temperature gradually lowers with increasing pressure and completely vanishes above 12.0 GPa. Another transition sets in around 9.0 K at 5.5 GPa and persists up to the highest pressure of 45.0 GPa studied in this work. Intriguingly, we find that the first superconducting phase might coexist with a nontrivial rotational symmetry-protected topology in the pressure range of ∼3.8 to 4.3 GPa; the second one is associated with a structural phase transition from monoclinic C2/m to triclinic P-1 symmetry.

7.
Cancer ; 127(11): 1880-1893, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33784413

ABSTRACT

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer in China, however, publicly available, descriptive information on the clinical epidemiology of CRC is limited. METHODS: Patients diagnosed with primary CRC during 2005 through 2014 were sampled from 13 tertiary hospitals in 9 provinces across China. Data related to sociodemographic characteristics, the use of diagnostic technology, treatment adoption, and expenditure were extracted from individual medical records. RESULTS: In the full cohort of 8465 patients, the mean ± SD age at diagnosis was 59.3 ± 12.8 years, 57.2% were men, and 58.7% had rectal cancer. On average, 14.4% of patients were diagnosed with stage IV disease, and this proportion increased from 13.5% in 2005 to 20.5% in 2014 (P value for trend < .05). For diagnostic techniques, along with less use of x-rays (average, 81.6%; decreased from 90.0% to 65.7%), there were increases in the use of computed tomography (average, 70.4%; increased from 4.5% to 90.5%) and magnetic resonance imaging (average, 8.8%; increased from 0.1% to 20.4%) over the study period from 2005 to 2014. With regard to treatment, surgery alone was the most common (average, 50.1%), but its use decreased from 51.3% to 39.8% during 2005 through 2014; and the use of other treatments increased simultaneously, such as chemotherapy alone (average, 4.1%; increased from 4.1% to 11.9%). The average medical expenditure per patient was 66,291 Chinese Yuan (2014 value) and increased from 47,259 to 86,709 Chinese Yuan. CONCLUSIONS: The increasing proportion of late-stage diagnoses presents a challenge for CRC control in China. Changes in diagnostic and treatment options and increased expenditures are clearly illustrated in this study. Coupled with the recent introduction of screening initiatives, these data provide an understanding of changes over time and may form a benchmark for future related evaluations of CRC interventions in China.


Subject(s)
Colorectal Neoplasms , Facilities and Services Utilization , Health Expenditures , Aged , China/epidemiology , Colorectal Neoplasms/economics , Colorectal Neoplasms/epidemiology , Colorectal Neoplasms/therapy , Facilities and Services Utilization/economics , Facilities and Services Utilization/statistics & numerical data , Female , Health Expenditures/statistics & numerical data , Humans , Male , Middle Aged , Retrospective Studies , Surveys and Questionnaires
8.
Opt Express ; 29(24): 40668-40676, 2021 Nov 22.
Article in English | MEDLINE | ID: mdl-34809401

ABSTRACT

Coherence and steerability are two essential characteristics of quantum systems. For a two-qubit state, the first-order coherence and the maximal violation of linear steering inequality are used to operationally measure the degree of coherence and steerability, respectively. Recently, a complementary relation between first-order coherence and linear steerability has been proposed. In this paper, we report an experimental verification of the complementary relation by preparing biphoton polarization entangled states in an all-optical setup. We propose an operable method for experimental measurement of the first-order coherence and linear steerability and calculate the purity of the initial states by reconstructing the density matrices of them. The experimental results coincide with the theoretical predictions very well, which provides a valuable reference for the application of optical quantum technology.

9.
J Gastroenterol Hepatol ; 36(5): 1197-1207, 2021 May.
Article in English | MEDLINE | ID: mdl-32875595

ABSTRACT

BACKGROUND AND AIM: This study aimed to clarify health-related quality of life (HRQoL) of patients with colorectal precancer and colorectal cancer (CRC) in China and to better understand related utility scores. METHODS: A hospital-based cross-sectional survey was conducted in precancer and CRC patients from 2012 to 2014, covering 12 provinces in China. HRQoL was assessed with EuroQol 5-Dimensions 3-Levels. Utility scores were derived using Chinese value set. A multivariate regression model was established to explore potential predictors of utility scores. RESULTS: A total of 376 precancer (mean age 58.7 years, 61.2% men) and 2470 CRC patients (mean age 58.6 years, 57.6% men) were included. In five dimensions, there was a certain percentage of problem reported among precancer (range: 12.0% to 36.7%) and CRC (range: 32.4% to 50.3%) patients, with pain/discomfort being the most serious dimension. Utility scores of precancer and CRC patients were 0.870 (95% confidence interval [CI], 0.855-0.886) and 0.751 (95% CI, 0.742-0.759), both of which were lower than those of general Chinese population (0.960 [95% CI, 0.960-0.960]). Utilities for patients at stage I to stage IV were 0.742 (95% CI, 0.715-0.769), 0.722 (95% CI, 0.705-0.740), 0.756 (95% CI, 0.741-0.772), and 0.745 (95% CI, 0.742-0.767), respectively. Multivariate analysis showed that therapeutic regimen, time point of the interview, education, occupation, annual household income, and geographic region were associated with utilities of CRC patients. CONCLUSION: Health-related quality of life of both precancer and CRC patients in China declined considerably. Utility scores differed by sociodemographic and clinical characteristics, and findings of these utilities may facilitate implementation of further cost-utility evaluations.


Subject(s)
Colorectal Neoplasms , Quality of Life , Adolescent , Adult , Aged , Aged, 80 and over , China , Colorectal Neoplasms/pathology , Colorectal Neoplasms/psychology , Colorectal Neoplasms/therapy , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Multivariate Analysis , Neoplasm Staging , Regression Analysis , Young Adult
10.
Qual Life Res ; 30(3): 841-854, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32930993

ABSTRACT

PURPOSE: To compare the performance of three-level EuroQol five-dimensions (EQ-5D-3L) and five-level EuroQol five-dimensions (EQ-5D-5L) among common cancer patients in urban China. METHODS: A hospital-based cross-sectional survey was conducted in three provinces from 2016 to 2018 in urban China. Patients with breast cancer, colorectal cancer, or lung cancer were recruited to complete the EQ-5D-3L and EQ-5D-5L questionnaires. Response distribution, discriminatory power (indicator: Shannon index [H'] and Shannon evenness index [J']), ceiling effect (the proportion of full health state), convergent validity, and health-related quality of life (HRQoL) were compared between the two instruments. RESULTS: A total of 1802 cancer patients (breast cancer: 601, colorectal cancer: 601, lung cancer: 600) were included, with the mean age of 55.6 years. The average inconsistency rate was 4.4%. Compared with EQ-5D-3L (average: H' = 1.100, J' = 0.696), an improved discriminatory power was observed in EQ-5D-5L (H' = 1.473, J' = 0.932), especially contributing to anxiety/depression dimensions. The ceiling effect was diminished in EQ-5D-5L (26.5%) in comparison with EQ-5D-3L (34.5%) (p < 0.001), mainly reflected in the pain/discomfort and anxiety/depression dimensions. The overall utility score was 0.790 (95% CI 0.778-0.801) for EQ-5D-3L and 0.803 (0.790-0.816) for EQ-5D-5L (p < 0.001). A similar pattern was also observed in the detailed cancer-specific analysis. CONCLUSIONS: With greater discriminatory power, convergent validity and lower ceiling, EQ-5D-5L may be preferable to EQ-5D-3L for the assessment of HRQoL among cancer patients. However, higher utility scores derived form EQ-5D-5L may also lead to lower QALY gains than those of 3L potentially in cost-utility studies and underestimation in the burden of disease.


Subject(s)
Neoplasms/epidemiology , Psychometrics/methods , Quality of Life/psychology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Reproducibility of Results
11.
Phys Rev Lett ; 124(1): 016402, 2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31976722

ABSTRACT

Spin-gapless semimetals (SGSMs), which generate 100% spin polarization, are viewed as promising semi-half-metals in spintronics with high speed and low consumption. We propose and characterize a new Z_{2} class of topological nodal line (TNL) in SGSMs. The proposed TNLSGSMs are protected by space-time inversion symmetry or glide mirror symmetry with two-dimensional (2D) fully spin-polarized nearly flat surface states. Based on first-principles calculations and effective model analysis, a series of high-quality materials with R3[over ¯]c and R3c space groups are predicted to realize such TNLSGSMs (chainlike). The 2D fully spin-polarized nearly flat surface states may provide a route to achieving equal spin pairing topological superconductivity as well as topological catalysts.

12.
Phys Rev Lett ; 125(1): 017002, 2020 Jul 03.
Article in English | MEDLINE | ID: mdl-32678627

ABSTRACT

The Kohn-Luttinger mechanism for unconventional superconductivity (SC) driven by weak repulsive electron-electron interactions on a periodic lattice is generalized to the quasicrystal (QC) via a real-space perturbative approach. The repulsive Hubbard model on the Penrose lattice is studied as an example, on which a classification of the pairing symmetries is performed and a pairing phase diagram is obtained. Two remarkable properties of these pairing states are revealed, due to the combination of the presence of the point-group symmetry and the lack of translation symmetry on this lattice. First, the spin and spacial angular momenta of a Cooper pair is decorrelated: for each pairing symmetry, both spin-singlet and spin-triplet pairings are possible even in the weak-pairing limit. Second, the pairing states belonging to the 2D irreducible representations of the D_{5} point group can be time-reversal-symmetry-breaking topological SCs carrying spontaneous bulk super current and spontaneous vortices. These two remarkable properties are general for the SCs on all QCs, and are rare on periodic lattices. Our work starts the new area of unconventional SCs driven by repulsive interactions on the QC.

13.
Tob Control ; 29(2): 191-199, 2020 03.
Article in English | MEDLINE | ID: mdl-31073096

ABSTRACT

BACKGROUND: Lung cancer is substantially attributable to smoking, but detailed related estimates on smoking-attributable expenditure (SAE) in China are not available yet, which could inform tobacco control and cancer prevention initiatives. METHODS: A prevalence-based approach was adopted to estimate the total SAE, including direct expenditure (medical and non-medical) and indirect cost (disability and premature death). Detailed per-patient data on direct expenditure and work-loss days were acquired from a unique multicentre survey in China. Other parameters were from literatures and official reports. RESULTS: The total estimated SAE of lung cancer was US$5249 million in China in 2015 (0.05 % of gross domestic product for China). The estimated direct SAE was US$1937 million (36.9 % of the total SAE), accounting for 0.29 % of total healthcare expenditure for China. The medical and non-medical direct expenditures were US$1749 million and US$188 million, respectively. The estimated indirect cost was US$3312 million (63.1 % of the total SAE), including US$377 million due to disability and US$2935 million due to premature death. The SAE increased with age, peaking at 60-64 years (US$1004 million), and was higher among men, in urban areas and in eastern China. If smoking prevalence was reduced to 20%, as is the goal of Healthy China 2030, the total SAE would be decreased by 4.9 %. CONCLUSIONS: Smoking-attributable economic burden caused by lung cancer was substantial in China in 2015, and will continue increasing given current trends in lung cancer. However, future economic burden can be prevented with implementation of effective tobacco control and other interventions.


Subject(s)
Cost of Illness , Lung Neoplasms/epidemiology , Tobacco Smoking/adverse effects , Adult , Age Distribution , Aged , Aged, 80 and over , China/epidemiology , Female , Health Care Costs/statistics & numerical data , Health Expenditures/statistics & numerical data , Humans , Lung Neoplasms/economics , Lung Neoplasms/etiology , Male , Middle Aged , Mortality, Premature , Prevalence , Sex Distribution , Surveys and Questionnaires , Tobacco Smoking/economics , Tobacco Smoking/epidemiology
14.
Cell Physiol Biochem ; 46(4): 1525-1535, 2018.
Article in English | MEDLINE | ID: mdl-29689546

ABSTRACT

BACKGROUND/AIMS: The metabolic features of cancer cells have long been acknowledged to be altered and to provide new therapeutic opportunities. The expression of glycolytic enzyme enolase 2 (ENO2) was found to be closely associated with the clinical features of acute lymphoblastic leukemia (ALL) patients, but its functions remain unclear in ALL. METHODS: We evaluated the association between ENO2 mRNA expression in bone marrow mononuclear cells (BM-MNCs) and the efficacy of chemotherapy, and further explored the function of ENO2 in ALL. The molecular mechanisms of ENO2 expression and its effects on cell growth, glycolysis and glucocorticoid resistance were explored by Cell Counting Kit-8, glucose-consumption assay, Quantitative RT-PCR, Western blotting and in vivo tumorigenesis in NOD/SCID mice. RESULTS: The results showed that ENO2 mRNA expression in BM-MNCs was significantly decreased when patients completed induction chemotherapy and reached complete remission (CR). ENO2 mRNA expression was increased when patients suffered relapse. Functional studies demonstrated that ENO2 promoted cell growth, glycolysis, and glucocorticoid resistance, all of which were effectively inhibited when ENO2 was silenced with shRNAs. Further studies revealed that ENO2 up-regulated various glycolysis-related genes and enhanced Akt activity with subsequent glycogen synthase kinase3ß (GSK-3ß) phosphorylation, inducing cell proliferation and glycolysis. The combination of silencing ENO2 and 2-deoxyglucose (2-DG) synergistically inhibited leukemia cell survival. CONCLUSIONS: These results indicate that ENO2 may be a biological marker for monitoring chemotherapeutic efficacy and relapse in ALL. ENO2 may provide a potential therapeutic strategy for ALL.


Subject(s)
Phosphopyruvate Hydratase/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Deoxyglucose/pharmacology , Dexamethasone/pharmacology , Drug Resistance, Neoplasm , Female , Glucocorticoids/pharmacology , Glucocorticoids/therapeutic use , Glucose Transporter Type 1/genetics , Glucose Transporter Type 1/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Glycolysis/drug effects , HEK293 Cells , Humans , Jurkat Cells , Mice , Mice, Inbred NOD , Mice, SCID , Phosphopyruvate Hydratase/antagonists & inhibitors , Phosphopyruvate Hydratase/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Signal Transduction/drug effects , Transplantation, Heterologous
15.
Phys Rev Lett ; 121(21): 217001, 2018 Nov 23.
Article in English | MEDLINE | ID: mdl-30517799

ABSTRACT

We model the newly synthesized magic-angle-twisted bilayer graphene superconductor with two p_{x,y}-like Wannier orbitals on the superstructure honeycomb lattice, where the hopping integrals are constructed via the Slater-Koster formulism by symmetry analysis. The characteristics exhibited in this simple model are well consistent with both the rigorous calculations and experiment observations. A van Hove singularity and Fermi-surface (FS) nesting are found in the doping levels relevant to the correlated insulator and unconventional superconductivity revealed experimentally, based on which we identify the two phases as weak-coupling FS instabilities. Then, with repulsive Hubbard interactions turned on, we performed random-phase-approximation based calculations to identify the electron instabilities. As a result, we find chiral d+id topological superconductivity bordering the correlated insulating state near half-filling, identified as noncoplanar chiral spin-density wave ordered state, featuring the quantum anomalous Hall effect. The phase diagram obtained in our approach is qualitatively consistent with experiments.

16.
Phys Rev Lett ; 121(18): 186801, 2018 Nov 02.
Article in English | MEDLINE | ID: mdl-30444417

ABSTRACT

Majorana bound states often occur at the end of a 1D topological superconductor. Validated by a new bulk invariant and an intuitive edge argument, we show the emergence of one Majorana Kramers pair at each corner of a square-shaped 2D topological insulator proximitized by an s_{±}-wave (e.g., Fe-based) superconductor. We obtain a phase diagram that addresses the relaxation of crystal symmetry and edge orientation. We propose two experimental realizations in candidate materials. Our scheme offers a higher-order and higher-temperature route for exploring non-Abelian quasiparticles.

17.
J Nanobiotechnology ; 16(1): 83, 2018 Oct 27.
Article in English | MEDLINE | ID: mdl-30368238

ABSTRACT

BACKGROUND: In order to explore the possibility of treating breast cancer by local photo-therapy, a photothermal agents loaded in situ hydrogel was established. In detail, The Cu2MnS2 nanoplates were prepared by one-pot synthesis and, the thermosensitive Pluronic F127 was used as the hydrogel matrix. The Cu2MnS2 nanoplates and the hydrogel were characterized by morphous, particle size, serum stability, photothermal performance upon repeated 808 nm laser irradiation as well as the rheology features. The therapeutic effects of the Cu2MnS2 nanoplates and the hydrogel were evaluated qualitatively and quantitatively in 4T1 mouse breast cancer cells. The retention, photothermal efficacy, therapeutic effects and systemic toxicity of the hydrogel were assessed in tumor bearing mouse model. RESULTS: The Cu2MnS2 nanoplates with a diameter of about 35 nm exhibited satisfying serum stability, photo-heat conversion ability and repeated laser exposure stability. The hydrogel encapsulation did not negatively influence the above features of the photothermal agent. The nanoplates loaded in situ hydrogel shows a phase transition at body temperature and, as a result, a long retention in vivo. CONCLUSIONS: The photothermal agent embedded hydrogel played a promising photothermal therapeutic effects in tumor bearing mouse model with low systemic toxicity after peritumoral administration.


Subject(s)
Copper/chemistry , Hydrogels/chemistry , Hyperthermia, Induced , Injections , Mammary Neoplasms, Animal/therapy , Manganese/chemistry , Nanoparticles/chemistry , Phototherapy , Sulfides/chemistry , Animals , Cell Line, Tumor , Female , Mammary Neoplasms, Animal/pathology , Mice, Inbred BALB C , Nanoparticles/ultrastructure , Poloxamer/chemistry
18.
Phys Rev Lett ; 118(6): 067702, 2017 Feb 10.
Article in English | MEDLINE | ID: mdl-28234544

ABSTRACT

We fabricate high-mobility p-type few-layer WSe_{2} field-effect transistors and surprisingly observe a series of quantum Hall (QH) states following an unconventional sequence predominated by odd-integer states under a moderate strength magnetic field. By tilting the magnetic field, we discover Landau level crossing effects at ultralow coincident angles, revealing that the Zeeman energy is about 3 times as large as the cyclotron energy near the valence band top at the Γ valley. This result implies the significant roles played by the exchange interactions in p-type few-layer WSe_{2}, in which itinerant or QH ferromagnetism likely occurs. Evidently, the Γ valley of few-layer WSe_{2} offers a unique platform with unusually heavy hole carriers and a substantially enhanced g factor for exploring strongly correlated phenomena.

19.
Phys Rev Lett ; 116(6): 066801, 2016 Feb 12.
Article in English | MEDLINE | ID: mdl-26919004

ABSTRACT

While strong topological insulators (STIs) were experimentally realized soon after they were theoretically predicted, a weak topological insulator (WTI) has yet to be unambiguously confirmed. A major obstacle is the lack of distinct natural cleavage surfaces to test the surface selective hallmark of a WTI. With a new scheme, we discover that ß-Bi4X4 (X=Br, I), dynamically stable or synthesized before, can be a prototype WTI with two natural cleavage surfaces, where two anisotropic Dirac cones stabilize and annihilate, respectively. We further find four surface-state Lifshitz transitions under charge doping and two bulk topological phase transitions under uniaxial strain. Near the WTI-STI transition, there emerges a novel Weyl semimetal phase, in which the Fermi arcs generically appear at both cleavage surfaces whereas the Fermi circle only appears at one selected surface.

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