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1.
Nat Mater ; 23(6): 782-789, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38491147

RESUMO

Coupling of spin and charge currents to structural chirality in non-magnetic materials, known as chirality-induced spin selectivity, is promising for application in spintronic devices at room temperature. Although the chirality-induced spin selectivity effect has been identified in various chiral materials, its Onsager reciprocal process, the inverse chirality-induced spin selectivity effect, remains unexplored. Here we report the observation of the inverse chirality-induced spin selectivity effect in chiral assemblies of π-conjugated polymers. Using spin-pumping techniques, the inverse chirality-induced spin selectivity effect enables quantification of the magnitude of the longitudinal spin-to-charge conversion driven by chirality-induced spin selectivity in different chiral polymers. By widely tuning conductivities and supramolecular chiral structures via a printing method, we found a very long spin relaxation time of up to several nanoseconds parallel to the chiral axis. Our demonstration of the inverse chirality-induced spin selectivity effect suggests possibilities for elucidating the puzzling interplay between spin and chirality, and opens a route for spintronic applications using printable chiral assemblies.

2.
Nano Lett ; 22(7): 2907-2914, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35362973

RESUMO

The quantum-confinement effect profoundly influences the exciton energy-level structures and recombination dynamics of semiconductor nanostructures but remains largely unexplored in traditional one-dimensional nanowires mainly due to their poor optical qualities. Here, we show that in defect-tolerant perovskite material of highly luminescent CsPbBr3 nanowires, the exciton's center-of-mass motion perpendicular to the axial direction is severely confined. This is reflected in the two sets of photoluminescence spectra emitted from a single CsPbBr3 nanowire, each of which consists of doublet peaks with linear polarizations perpendicular and parallel to the axial direction. Moreover, different exciton states can be mixed by the Rashba spin-orbit coupling effect, resulting in two single photoluminescence peaks with linear polarizations both along the nanowire axis. The above findings mark the emergence of an ideal platform for the exploration of intrinsic one-dimensional exciton photophysics and optoelectronics, thus bridging the long-missing research gap between the well-studied two- and zero-dimensional semiconductor nanostructures.

3.
J Am Chem Soc ; 144(48): 22242-22250, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36399117

RESUMO

The combination of chirality and semiconducting properties has enabled chiral metal-halide semiconductors (MHS) to be promising candidates for spin- and polarization-resolved optoelectronic devices. Although several chiral MHS with rich chemical and structural diversity have been reported lately, the macroscopic origin of chiroptical activity remains elusive. Here, combining spectroscopic measurements and Mueller matrix analysis, we discover that the previously reported "apparent" anisotropy factor measured from circular dichroism (CD) in chiral MHS thin films is not an intrinsic chiroptical property, but rather, arising from an interference between the film's linear birefringence (LB) and linear dichroism (LD). We verify the presence of LB and LD effects in both one-dimensional and zero-dimensional chiral MHS thin films. We establish spectroscopic methods to decouple the genuine CD from other spurious contributions, which allows a quantitative comparison of the intrinsic chiroptical activity across different chiral MHS. The relationship between the structure and the genuine chiroptical activity is then uncovered, which is well described by the chirality-induced spin-orbit coupling in the chiral structures. Our study unveils the macroscopic origin of chiroptical activity of chiral MHS and provides design principles for obtaining high anisotropic factors for future chiral optoelectronic applications.

4.
J Chem Phys ; 156(12): 124706, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35364870

RESUMO

Exciton transport plays a central role in optoelectronic and photonic devices. In quasi-two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs), tightly bound excitons are found to diffuse within 2D layers rapidly with a non-monotonic temperature dependence. Surprisingly, the interlayer exciton diffusion is quite effective as well despite the large interlayer distance. This is in sharp contrast to electron transport, where the interlayer mobility is several orders of magnitude smaller than the intralayer one. Here, we show that the unusual exciton diffusion behaviors can be systematically modeled via the excitonic band structure arising from a long-range dipolar coupling. Coherent exciton motion is interrupted by scattering of impurities at low temperatures and of acoustic/optical phonons at high temperatures. Acoustic and optical phonons modulate the dipole-dipole distance and the dipole orientation, respectively. The ratio of intralayer and interlayer diffusion constants, Dxx/Dzz, is comparable to az/ax with az and ax being the interlayer and intralayer lattice constants of 2D HOIPs, respectively. The efficient and omnidirectional exciton diffusion suggests a great potential of 2D HOIPs in novel excitonic and polaritonic applications.

5.
Phys Chem Chem Phys ; 21(40): 22293-22301, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31576823

RESUMO

Self-trapped excitons (STEs) in two-dimensional (2D) hybrid organic-inorganic perovskites (HOIPs) emit broadband white light, suggesting the great potential of 2D HOIPs in low-cost lighting and display applications. A prerequisite for understanding STEs' properties is a correct identification of the underlying interaction that leads to the STEs. Here, we show that the long-range polar coupling between electrons and optical phonons is quenched in 2D HOIPs' tightly bound excitons and cannot effect STEs. Rather, the STEs are induced by a short-range optical deformation potential (ODP) arising from the phonon-modulated Pb-X quantum-well thickness. Interaction between transition dipoles in adjacent PbX6 (X = Br or I) octahedra gives rise to highly anisotropic intra- and inter-layer exciton bandwidths. In flat (001) 2D HOIPs, both the ODP and the exciton bandwidths are susceptible to out-of-plane PbX6 tilting but not to the in-plane one, and their interplay can quantitatively account for the observed temperature and structure dependences of luminescence associated with STEs. In corrugated (011) 2D HOIPs, the exciton bandwidth is further reduced and the resultant STEs have a stronger lattice distortion and broader luminescence spectrum. Our results reveal the mechanism of STE formation and suggest ways of tuning STEs and associated broadband luminescence in 2D HOIPs.

6.
J Chem Phys ; 151(20): 204106, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779336

RESUMO

The Rashba effect, which shifts the conduction band extremum from wavevector k = 0 to |k| = k0 ≠ 0 with an energy gain of ER, has been frequently invoked to explain outstanding optoelectronic properties in hybrid organic-inorganic perovskites (HOIPs). For two-dimensional (2D) layered HOIPs, the only direct experimental evidence of the Rashba effect to date is resonant free-carrier absorption (FCA), which has been attributed to direct optical transition between the Rashba subbands at |k| = k0 ≠ 0 with photon energy ℏω = 4ER. Here, we show that in layered perovskites, small polarons induced by a strong short-range coupling between electrons and optical phonons can also give rise to a resonant FCA at ℏω = 4Eb, with Eb being the polaron binding energy. The Rashba effect- and small-polaron-induced resonant FCA responses can be distinguished via an applied electric field, which moves the resonance peak to a higher or lower photon energy in the former but splits the peak into two in the latter, suggesting that electric-field-modulated FCA can help prove and quantify the Rashba effect and/or small polarons in layered perovskites.

7.
J Chem Phys ; 151(14): 144702, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615224

RESUMO

Carrier scattering processes are studied in CH3NH3PbI3 using temperature-dependent four-wave mixing experiments. Our results indicate that scattering by ionized impurities limits the interband dephasing time (T2) below 30 K, with strong electron-phonon scattering dominating at higher temperatures (with a time scale of 125 fs at 100 K). Our theoretical simulations provide quantitative agreement with the measured carrier scattering rate and show that the rate of acoustic phonon scattering is enhanced by strong spin-orbit coupling, which modifies the band-edge density of states. The Rashba coefficient extracted from fitting the experimental results (γc = 2 eV Å) is in agreement with calculations of the surface Rashba effect and recent experiments using the photogalvanic effect on thin films.

8.
Phys Chem Chem Phys ; 19(23): 14907-14912, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28569918

RESUMO

Slow electron-hole recombination, characterized by the bimolecular coefficient k2 in hybrid organic-inorganic perovskites (HOIPs), is a key to their outstanding photovoltaic performance. The measured k2 in HOIPs strongly deviates from k2 ∝ T-3/2 (T is the temperature) in typical direct-gap semiconductors. Here we show that the observed temperature dependence can be quantitatively accounted for by phonon-assisted recombination of electrons and holes located at the band extrema, which become indirect due to the Rashba effect. Polar optical phonons are most effective in facilitating this indirect recombination. The variation in k2 in HOIPs among different studies in the literature can be attributed to different Rashba strengths in their samples. Our results indicate that the confluence of the Rashba effect and polar coupling transform HOIPs into a unique indirect semiconductor that can accommodate both strong optical absorption and slow carrier dynamics.

9.
BMC Public Health ; 14: 1004, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25257142

RESUMO

BACKGROUND: High breast cancer mortality has been attributed to lack of public awareness, which leads to late diagnoses. As little is known about the level of knowledge and awareness of breast cancer in China, this study was designed to explore it among women in Eastern China. METHODS: We conducted a cross-sectional survey covering 122,058 females around Shandong, Hebei, Jiangsu and Tianjin, in Eastern China, using in-person interviews based on a self-designed structured questionnaire. Student's t-test, Pearson's χ2 test, reliability analysis, exploratory factor analysis, univariate and multivariate logistic regression analyses were performed in the statistical analysis. RESULTS: The results showed poor awareness of breast cancer among women aged 25-70 years in Eastern China. Only 18.6% of women were highly aware in the study, whereas 81.4% were poorly aware. Among all participants, family history of breast cancer was the best accepted risk factor for breast cancer (awareness rate 31.5%), followed by menarche at age before 12 (11.2%), no parity or late childbirth (13.9%), menopause at a late age (13.7%), high-fat diets (19.1%), long time drinking (19.5%) and long-term use of estrogen drugs (20.7%). Multivariate logistic regression analysis (α = 0.05) identified nine variables that predicted awareness of breast cancer: age (OR = 0.975, 95% CI: 0.960-0.990), location (OR = 1.675, 95% CI: 1.602-1.752), occupation (OR = 4.774, 95% CI: 4.316-5.281), family history of breast cancer (OR = 1.234, 95% CI: 1.073-1.420), household annual income (OR = 0.418, 95% CI: 0.400-0.436), behavioral prevention score (OR = 4.137, 95% CI: 3.991-4.290), no smoking (OR = 2.113, 95% CI: 1.488-2.999), no drinking (OR = 1.427, 95% CI: 1.018-2.000), overall life satisfaction (OR = 0.707, 95% CI: 0.683-0.731). CONCLUSIONS: Our study indicates insufficient awareness of breast cancer among women in Eastern China, and an urgent need for health education programs on this subject.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/psicologia , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Idoso , Neoplasias da Mama/diagnóstico , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Inquéritos e Questionários
10.
J Phys Chem Lett ; 15(30): 7770-7774, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39047155

RESUMO

Organic and biological materials are often chiral. Chiral polymers, as recent experiments indicate, facilitate spin-charge conversion: a charge current results in a spin polarization and vice versa, dubbed chirality-induced spin selectivity (CISS) and inverse CISS (ICISS). While CISS/ICISS in crystalline chiral systems such as tellurium can be understood in terms of their chirality- and spin-dependent band structure, such a picture becomes inapplicable to disordered chiral polymers, where carrier transport is via hopping rather than band conduction. Here, we develop a microscopic theory to describe CISS and ICISS in disordered chiral organics, in which chirality-induced geometric spin-orbit coupling leads to a purely geometric spin-dependent Berry phase in electron hops involving triads, whose orientations are dictated by the material's chirality. Our theory reveals a central role of spin-flip hopping, which suppresses CISS but enables ICISS.

11.
Anal Chem ; 85(6): 3340-6, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23413882

RESUMO

Here we report the effect of the signaling probe conformation on sensor performance of a "signal-on" folding-based electrochemical DNA sensor. The sensor is comprised of a methylene blue (MB)-modified signaling probe and an unlabeled capture probe that partially hybridize to each other at the distal end. In presence of the full-complement target which binds to the unlabeled capture probe, the labeled signaling probe is released. Two different signaling probes were used in this study, in which one is capable of assuming a stem-loop conformation (SLP-MB), whereas the other probe adopts a flexible linear conformation (LP-MB). In the presence of the full complement target DNA, both sensors showed a large increase in MB current when interrogated using alternating current (ac) voltammetry, verifying the release of the signaling probe. Overall, the SLP-MB sensor showed higher % signal enhancement; the LP-MB sensor, however, showed distinctly faster binding kinetics when interrogated under the same experimental conditions. The SLP-MB sensor displayed a wider usable ac frequency range when compared to the LP-MB sensor. Despite these differences, the detection limit and dynamic range were found to be similar among the two sensors. In addition to 6-mercapto-1-hexanol, longer chain hydroxyl-terminated alkanethiols were used to construct these sensors. Our results showed that sensors fabricated with longer chain diluents, independent of the sensor architecture, were not only functional, the signaling capability was significantly enhanced.


Assuntos
Técnicas Biossensoriais/métodos , DNA/análise , Técnicas Eletroquímicas/métodos , Azul de Metileno/química , Transdução de Sinais
12.
BMC Public Health ; 12: 368, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22612880

RESUMO

BACKGROUND: There has been a sharp increase in the incidence of breast cancer in China in recent years. A number of female physical characteristics, such as age at menarche, menopause, first birth and the duration of breastfeeding, have been linked to breast cancer, yet data on these factors in Chinese women is largely missing both for aggregate and age-specific data. Thus, the objective of this study was to explore changes in female menstrual and childbearing characteristics as a possible explanation for increasing rates of breast cancer in this country. METHOD: From July to September 2008, a population based cross-sectional breast cancer survey covering 124,758 females from 4 provinces or cities in Eastern China was carried out, using multi-stage and cluster methods. In-person interviews based on a self-designed structured questionnaire were performed, in which female physiological and reproductive factors, such as age at menarche and menopause, menstrual cycle history, childbearing history, breastfeeding methods, abortions or miscarriage, were included. For every 10-year age category, the subjects were divided, and across those age groups, all the above factors were compared respectively and changes in physical and childbearing characteristics were evaluated. ANOVA was used to compare the differences across the groups. RESULTS: A total of 122058 subjects were included in the final analysis. The mean age at menarche was 15.39 years, the mean number of full-term pregnancies was 1.58, the mean duration of breastfeeding was 22.68 months, the mean age at first birth was 23.75 years, the mean frequency of miscarriage was 0.36, and the mean age at menopause was 48.63 years. Significant differences across the several age groups were noted for the age at menarche, number of full-term pregnancies, accumulated duration of breastfeeding, age at first birth, number of miscarriages, and age at menopause. These data clearly showed a gradual shift towards an earlier age at menarche, fewer pregnancies and shorter breastfeeding lengths. CONCLUSIONS: Significant changes in female physical and childbearing characteristics across a number of different age ranges were detected. These changes may be related to the increasing trend of breast cancer in China.


Assuntos
Aleitamento Materno , Neoplasias da Mama/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Menarca/fisiologia , Parto/fisiologia , Aborto Espontâneo/epidemiologia , Adulto , Idoso , Análise de Variância , Aleitamento Materno/estatística & dados numéricos , Neoplasias da Mama/diagnóstico , China/epidemiologia , Análise por Conglomerados , Estudos Transversais , Feminino , Humanos , Idade Materna , Pessoa de Meia-Idade , Paridade/fisiologia , Gravidez , História Reprodutiva , Características de Residência , Fatores de Risco , Inquéritos e Questionários
13.
Mater Horiz ; 9(2): 740-747, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-34878471

RESUMO

The introduction of chiral organic ligands into hybrid organic-inorganic perovskites (HOIPs) results in chiral perovskites, which exhibit natural optical activities (NOAs) such as circularly polarized luminescence (CPL). CPL can be observed in achiral HOIPs under a magnetic field as well. Here, we systematically study the temperature- and magnetic field-dependence of both circular polarization and total intensity in chiral HOIPs. Pronounced CPL polarization is observed in polycrystalline films of chiral HOIPs, which can be further tuned by an applied magnetic field. The magnetic field also modifies the total intensity of CPL, giving rise to magneto-PL in chiral HOIPs, which is observable even at room temperature. The observed field and temperature-dependence of polarization can be well accounted for by a recently developed theory of chiral HOIPs, where the materials' helicity gives rise to a novel spin-orbit coupling (SOC). The observed MPL can be quantitatively accounted for by the interplay of exciton fine structures and the magnetic field. Our study suggests that the magnetic field provides an effective means to manipulate both the polarization and intensity of CPL in chiral HOIPs, which can be exploited for novel device applications.

14.
Nat Commun ; 13(1): 483, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35078984

RESUMO

The Rashba splitting in hybrid organic-inorganic lead-halide perovskites (HOIP) is particularly promising and yet controversial, due to questions surrounding the presence or absence of inversion symmetry. Here we utilize two-photon absorption spectroscopy to study inversion symmetry breaking in different phases of these materials. This is an all-optical technique to observe and quantify the Rashba effect as it probes the bulk of the materials. In particular, we measure two-photon excitation spectra of the photoluminescence in 2D, 3D, and anionic mixed HOIP crystals, and show that an additional band above, but close to the optical gap is the signature of new two-photon transition channels that originate from the Rashba splitting. The inversion symmetry breaking is believed to arise from ionic impurities that induce local electric fields. The observation of the Rashba splitting in the bulk of HOIP has significant implications for the understanding of their spintronic and optoelectronic device properties.

15.
Patient Educ Couns ; 105(7): 1818-1827, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34952749

RESUMO

OBJECTIVE: To summarize the awareness levels of breast cancer (BC) worldwide and investigate factors associated with BC awareness to determine differences in awareness between China and other countries. METHODS: This systematic review followed the PRISMA guidelines and included 92 articles up to July, 2021. We calculated percentages for BC awareness levels and conducted subgroup analysis and cumulative meta-analysis. RESULTS: A total 84% (95% confidence interval [95%CI]: 78-90%) of women knew about BC; however, only 51% (95%CI: 37-66%) and 40% (95%CI: 24-56%) of women were aware of BC symptoms and BC risk factors, respectively. The most commonly known BC symptom was breast lump (71%, 95%CI: 62-80%), and BC family history was the most well-known BC risk factor (61%, 95%CI: 54-69%). Subgroup analysis showed lower awareness levels among Chinese and Asian women than women from other countries. Cumulative meta-analysis showed no obvious progress in BC awareness levels over time. We investigated 15 awareness-related factors, the most frequent of which were education level (61.8%), occupation (29.4%), and age (26.5%). CONCLUSION: BC awareness levels remain low. Improving BC awareness is critical, especially in developing countries. PRACTICE IMPLICATIONS: Effective education programs are urgently needed to improve women's BC awareness.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/diagnóstico , China , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos
16.
Nat Commun ; 12(1): 2192, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33850150

RESUMO

Single perovskite nanocrystals have attracted great research attention very recently due to their potential quantum-information applications, which critically depend on the development of powerful optical techniques to resolve delicate exciton photophysics. Here we have realized resonant and near-resonant excitations of single perovskite CsPbI3 nanocrystals, with the scattered laser light contributing to only ~10% of the total collected signals. This allows us to estimate an ultranarrow photoluminescence excitation linewidth of ~11.32 µeV for the emission state of a single CsPbI3 nanocrystal, corresponding to an exciton dephasing time of ~116.29 ps. Meanwhile, size-quantized acoustic phonons can be resolved from a single CsPbI3 nanocrystal, whose coupling with the exciton is proposed to arise from the piezoelectric potential. The ability to collect resonance fluorescence from single CsPbI3 nanocrystals, with the subsequent revelation of exciton-acoustic phonon coupling, has marked a critical step towards their steady advancement into superior quantum-light sources.

17.
Front Public Health ; 9: 767151, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976926

RESUMO

Objective: The aim of this study was to evaluate the relationship between lifestyle habits and health-related quality of life (HRQoL) among different ages who were initially diagnosed with breast cancer (within the first 2 weeks) and to determine the contribution of lifestyle habits factors on HRQoL. Methods: Patients with breast cancer were recruited from 22 hospitals in 11 provinces or municipalities in northern and eastern China. The Functional Assessment of Cancer Therapy-Breast Cancer (FACT-B) was used to measure HRQoL. Chi-square test, ANOVA, and multivariable generalized linear models were conducted to identify the differences in HRQoL between two age groups (age <50 years and ≥50 years) and to evaluate the contribution of lifestyle habits factors on HRQoL of patients with breast cancer. Results: About 1,199 eligible patients with breast cancer were used for analysis. Younger women (aged <50 years) appeared to show lower scores than older women (aged ≥50 years) in HRQoL subscales, including emotional well-being (p = 0.003), functional well-being (p = 0.006), breast cancer subscale (p = 0.038), and FACT-B Total scores (p = 0.028). Tea and alcohol consumption and being very satisfied with sleep and current life were the strongest predictors of higher HRQoL in younger group. Meanwhile, no coffee consumption, frequent participation in physical activities, high sleep satisfaction, and current life satisfaction were the key predictors of higher HRQoL in older women with breast cancer. Conclusion: The relationship of the nine lifestyle habit items with HRQoL differed among younger and older women. The associated variable of low HRQoL can help clinicians take intervention early in order to improve the prognosis of patients with breast cancer.


Assuntos
Neoplasias da Mama , Qualidade de Vida , Idoso , China , Feminino , Hábitos , Humanos , Estilo de Vida , Qualidade de Vida/psicologia , Inquéritos e Questionários
18.
Cancer Med ; 10(8): 2752-2762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33734613

RESUMO

BACKGROUND: X-ray repair cross-complementary 5 (XRCC5) and 6 (XRCC6) are critical for DNA repair. Few studies have assessed their association with breast cancer risk, and related gene-environment interactions remain poorly understood. This study aimed to determine the influence of XRCC5/6 polymorphisms on breast cancer risk, and their interactions with cigarette smoking, alcohol consumption, and sleep satisfaction. METHODS: The study included 1039 patients with breast cancer and 1040 controls. Four single-nucleotide polymorphisms of XRCC5 and two of XRCC6 were genotyped. Information about smoking, alcohol consumption, and sleep satisfaction was collected through questionnaires. Odds ratios (OR) and related 95% confidence intervals (95% CI) were assessed using unconditional logistic regression models. Gene-environment interactions were analyzed using logistic regression with multiplicative interaction models. RESULTS: XRCC5 rs16855458 was associated with increased breast cancer risk in the co-dominant (ptrend  = 0.003) and dominant (CA + AA vs. CC, OR = 1.29, 95% CI = 1.07-1.56, p = 0.008) genetic models after Bonferroni correction. The CG + GG genotype of XRCC6 rs2267437 was associated with an increased risk of estrogen receptor-negative/progesterone receptor-negative (ER-/PR-) breast cancer (CG + GG vs. CC: OR = 1.54, 95% CI = 1.12-2.13, p = 0.008) after Bonferroni correction. Moreover, an antagonistic interaction between XRCC5 rs16855458 and alcohol consumption (pinteraction  = 0.017), and a synergistic interaction between XRCC6 rs2267437 and sleep satisfaction were associated with breast cancer risk (pinteraction  = 0.0497). However, these interactions became insignificant after Bonferroni correction. CONCLUSION: XRCC5 rs16855458 was associated with breast cancer risk, and XRCC6 rs2267437 was associated with the risk of ER-/PR- breast cancer. Breast cancer risk associated with XRCC5 and XRCC6 polymorphisms might vary according to alcohol consumption and sleep satisfaction, respectively, and merit further investigation.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Neoplasias da Mama/genética , Autoantígeno Ku/genética , Fumar/genética , Adulto , Idoso , Povo Asiático/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Satisfação Pessoal , Polimorfismo de Nucleotídeo Único , Sono/fisiologia
19.
J Phys Chem Lett ; 11(20): 8638-8646, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32991181

RESUMO

Hybrid organic-inorganic perovskites (HOIPs) with chiral organic ligands exhibit highly spin-dependent transport and strong natural optical activity (NOA). Here we show that these remarkable features can be traced to a chirality-induced spin-orbit coupling (SOC), Hso = ατkzσz, which connects the carrier's spin (σz), its wave vector (kz), and the material's helicity (τ) along the screw direction with strength α controlled by the geometry of the organic ligands. This SOC leads to a macroscopic spin polarization in the presence of an electrical current and is responsible for the observed spin-selective transport. NOA originates from a coupling between the exciton's center-of-mass wave vector Kz and its circular polarization jzex, Hso' = α'τKzjzex, contributed jointly from the electron's and the hole's SOCs in an exciton. Our model provides a roadmap to achieve a strong and tunable chirality in HOIPs for novel applications utilizing carrier spin and photon polarization.

20.
Chin Med J (Engl) ; 133(22): 2660-2664, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33031140

RESUMO

BACKGROUND: Although breast-conserving surgery is one of the standard treatments for breast cancer, few studies have assessed its recent implementation in China. We aimed to clarify the current real-world status of breast-conserving surgery in China. METHODS: This cross-sectional survey relied on data collected by the Chinese Society of Breast Surgery (CSBrS) to examine patients who underwent this surgery between January 2018 and December 2018. The survey was conducted using a uniform electronic questionnaire to collect information, including clinical and pathological data on these patients. RESULTS: Overall, 4459 breast-conserving surgeries were performed in 34 member units of CSBrS, accounting for 14.6% of all breast cancer surgeries performed in these units during the study period. In patients who underwent breast-conserving surgery with information on tumor size available, more than half (61.2%) of the tumors were smaller than 2 cm in diameter, and only 87 (3.2%) tumors were larger than 4 cm in diameter. Among patients who underwent breast-conserving surgeries, 457 (10.2%) patients received neoadjuvant therapy before the surgery. Among patients with a reported margin width, 34 (2.0%) patients had a margin of ≤2 mm, and 1530 (88.2%) of them had a margin of >5 mm. CONCLUSIONS: This study demonstrated the rates of breast-conserving surgery in member units of the CSBrS, and introduced the characteristics and surgical margins of patients who underwent this surgery. This information helps describe the real-world status of breast-conserving surgery in China. TRIAL REGISTRATION: chictr.org.cn, ChiCTR1900026841; http://www.chictr.org.cn/showproj.aspx?proj=42783.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Neoplasias da Mama/cirurgia , China , Estudos Transversais , Humanos , Mastectomia , Estudos Retrospectivos
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