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1.
Phys Rev Lett ; 129(15): 156401, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269973

RESUMO

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

2.
Zhonghua Zhong Liu Za Zhi ; 44(7): 743-760, 2022 Jul 23.
Artigo em Zh | MEDLINE | ID: mdl-35880341

RESUMO

Objective: To systematically summarize and analyze the clinical research progress of therapeutic vaccines for cervical cancer or precancerous lesions. Methods: English databases (PubMed, Embase, Web of Science, Cochrane library, Proquest, and ClinicalTrails.gov) and Chinese databases (SinoMed, CNKI, WanFang, and VIP Database) were systematically searched to collect literature on therapeutic vaccines for cervical cancer or precancerous lesions from inception to February 18, 2021. After screening, we evaluated the risk of bias of included studies, and combed the basic information of the literature, research designs, information of vaccines, study patients, outcome indicators and so on, qualitatively summarized the clinical research progress. Results: A total of 71 studies were included in this systematic review, including 14 random controlled trials, 15 quasi-random controlled trials, 4 cohort studies, 1 case-control study, 34 case series studies and 3 case reports. The study patients included women aged 15~79 with cervical cancer or precancerous lesions in 18 countries from 1989 to 2021. On the one hand, there were 40 studies on therapeutic vaccines for cervical precancerous lesions (22 867 participants), involving 21 kinds of vaccines in 6 categories. Results showed 3 marketed vaccines (Cervarix, Gardasil, Gardasil 9) as adjuvant immunotherapies were significant effective in preventing the recurrence of precancerous lesions compared with the conization only. In addition, MVA E2 vaccine had been in phase Ⅲ clinical trials as a specific therapeutic vaccine, with relative literature showing it could eliminate most high-grade precancerous lesions. Therapeutic vaccines for precancerous lesions all showed good safety. On the other hand, there were 31 studies on therapeutic vaccines for cervical cancer (781 participants), involving 19 kinds of vaccines in 7categories, with none had been marketed. 25 studies were with no control group, showing the vaccines could effectively eliminate solid tumors, prevent recurrence, and prolong the median survival time. However, the vaccines effectiveness couldn't be statistically calculated due to the lack of a control group. As for the safety of therapeutic vaccines for cervical cancer, 9 studies showed that patients experienced serious adverse events after treatments, where 7 studies reported that serious adverse events occurred in patients couldn't be ruled out as the results of therapeutic vaccines. Conclusions: The literature review shows that the literature evidence for the therapeutic vaccines for cervical precancerous lesions is relatively mature compared with the therapeutic vaccines for cervical cancer. The four kinds of vaccines on the market are all therapeutic vaccines for precancerous lesions, but they are generally used as vaginal infection treatments or adjuvant immunotherapies for cervical precancerous lesions, not used for the specific treatments of cervical precancerous lesions. Other specific therapeutic vaccines are in the early stage of clinical trials, mainly phase Ⅰ/Ⅱ clinical trials with small sample size. The effectiveness and safety data are limited, and further research is still needed.


Assuntos
Vacinas Anticâncer , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Lesões Pré-Cancerosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Vacinas Anticâncer/uso terapêutico , Feminino , Humanos , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Lesões Pré-Cancerosas/terapia , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/prevenção & controle
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(3): 511-519, 2022 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-35701129

RESUMO

OBJECTIVE: To describe the distribution characteristics of inflammatory bowel disease among permanent residents in Yinzhou District, Ningbo City, and to understand the disease burden and development trend of inflammatory bowel disease in this area. METHODS: Using the retrospective cohort design, we collected the registration information of all permanent residents in the residents' health files of the Yinzhou Regional Health Information Platform from 2010 to 2020, and used electronic medical records to follow up their inflammatory bowel disease visits. A one-year wash-out period was set, and the patients who were diagnosed with the primary diagnosis for the first time after one year of registration were re-garded as new cases. The incidence density and 95% confidence interval (CI) of inflammatory bowel disease were estimated by Poisson distribution. RESULTS: From 2011 to 2020, a total of 1 496 427 permanent residents in Yinzhou District were included, of which 729 996 were male (48.78%). The total follow-up person-years were 8 081 030.82, and the median follow-up person-years were 5.41 [interquartile range (IQR): 5.29]. During the study period, there were 1 217 new cases of inflammatory bowel disease, of which males (624 cases, 51.27%) were more than females (593 cases, 48.73%). The total incidence density was 15.06/100 000 person-years (95%CI: 14.23, 15.93). Among all new cases, there were 1 106 cases (90.88%) of ulcerative colitis, with an incidence density of 13.69 per 100 000 person-years (95%CI: 12.89, 14.52); 70 cases (5.75%) of Crohn's disease, with an incidence density of 0.87 per 100 000 person-years (95%CI: 0.68, 1.09); and 41 cases (3.37%) of indeterminate colitis, with an incidence density of 0.51 per 100 000 person-years (95%CI: 0.36, 0.69). The median age of onset of ulcerative colitis was 50.82 years old (IQR: 18.77), with the highest proportion (15.01%) in the 45-49 years group. The incidence density of ulcerative colitis gradually increased with age, reaching a relatively high level in the 45-49 years group (20.53/100 000 person-years; 95%CI: 17.63, 23.78), followed by a slight increase. And the incidence density in the 65-69 years group was the highest (25.44/100 000 person-years; 95%CI: 20.85, 30.75), with a rapid decrease in the 75-79 years group. The median age of onset of Crohn's disease was 44.34 years (IQR: 33.41), with the highest proportion (12.86%) in the 25-29 years group. Due to the small number of new cases of Crohn's disease, the age distribution fluctuated greatly, with peaks both in young and old people. From 2011 to 2020, the incidence density of inflammatory bowel disease in Yinzhou District was at a low level from 2011 to 2013, and showed a rapid upward trend from 2014 to 2016, reaching a peak of 24.62 per 100 000 person-years in 2016 (95%CI: 21.31, 28.30), and slightly decreased in 2017-2020. CONCLUSION: The incidence density of inflammatory bowel disease in Yinzhou District from 2011 to 2020 was at a relatively high level, and medical institutions and health departments need to pay attention to the burden of disease caused by it.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Adolescente , Adulto , Doença Crônica , Colite Ulcerativa/epidemiologia , Doença de Crohn/epidemiologia , Feminino , Humanos , Incidência , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(3): 491-497, 2021 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-34145850

RESUMO

OBJECTIVE: To describe the epidemiological and etiological characteristics of hand, foot and mouth disease (HFMD) among children aged 5 years and younger in Ningbo after the access of entero-virus-A71 vaccine (2016 to 2019). METHODS: A retrospective cohort study were performed in children aged 5 years and younger in Ningbo from 2016 to 2019. Data for incidence of HFMD was collected from the National Notifiable Disease Surveillance Reporting System and the Electronic Medical Records (EMRs) System, while the demographic information was derived from the Immunization Information System. Speci-mens were detected by real-time fluorescence quantitative PCR and the Wilson method was used to estimate the incidence rate and 95% confidence interval. RESULTS: From 2016 to 2019, a total of 1 044 800 residential children were observed in this population-based cohort. In the study, 102 471 cases of HFMD were diagnosed in 2 651 081 person-years, revealing an overall incidence density of 3 865.25/100 000 person-years. There was no significant decline in the number of the cases after the vaccine was available. The number of the patients of hand foot mouth disease during the four years was 93 421, of whom 84 875 (90.85%) had only one incident record, while 8 946 (9.15%) had 2 or more cases in this period; there were 69 771 (66.06%) patients who only needed to see a doctor once for each disease, 19.92% of the patients needed to be treated twice, and 14 801 (14.02%) patients needed to go to the hospital or clinic three times or more. The incidence of HFMD showed obvious seasonality and periodicity, which mainly concentrated in April to July each year, and the epidemic cycle was 2 years; most of the cases were 1 to 3-year old children, with more cases in male. The incidence density varied across the region, with the highest density observed in Ninghai (4 524.76/100 000 person-years), followed by Xiangshan (3 984.22/100 000 person-years). In 3 748 library-conformed cases, 2 834(75.61%) were detected positive, among which enterovirus-A71, Cox-A16 and other enteroviruses accounted for 9.03%, 31.55% and 59.42%, respectively. During the study period, the cumulative coverage of enterovirus-A71 vaccine increased year by year, with the proportion of enterovirus-A71 and severe cases both gradually decreasing. CONCLUSION: The current status of hand, foot and mouth disease in Ningbo is still serious. Children under 3-year old (especially male children aged 1 year) were the key population for prevention and control. Vaccination might lead to changes in major pathogenic virus type, of which more attention should be paid to the potential impact on disease surveillance, prevention and control.


Assuntos
Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , Pré-Escolar , China/epidemiologia , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Lactente , Masculino , Estudos Retrospectivos
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 53(3): 485-490, 2021 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-34145849

RESUMO

OBJECTIVE: To describe the distribution and trend of infantile epilepsy among infants under 36 months in Ningbo, Zhejiang Province. METHODS: Using the birth cohort design, we retrospectively collected the local born infants in Ningbo national health information platform from 2015 to 2019, and took the first visit of epilepsy in the electronic medical record of the platform as the new case. The incidence density and 95% confidence interval (CI) of epilepsy were estimated by Poisson distribution. RESULTS: From 2015 to 2019, a total of 294 900 children were born in Ningbo, with male accounting for 51.92%. The total person-years of observation were 595 300, while the median follow-up person-years was 2.31 [interquartile range (IQR): 1.90]. There were 575 new onset epilepsy patients during the whole observation period. The total number of visits was 2 599, with an average of 4.52. The total incidence density was 96.59/100 000 person-years (95%CI: 88.85-104.82). The median age of onset was 13 months (IQR: 15), 0-12 months old infants had the highest incidence density (102.18/100 000 person-years), 25-36 months old infants had the lowest incidence density (89.68/100 000 person-years), and the difference was not statistically significant (P>0.05). The incidence density of male was 97.58/100 000 person-years, female was 95.53/100 000 person-years, and the difference was not statistically significant (P>0.05). Fenghua was the highest (130.54/100 000 person-years, 95%CI: 94.47-175.83) and Ninghai was the lowest (66.44/100 000 person-years, 95%CI: 47.02-91. 19), with significant difference (P < 0.05). There was no significant difference in the incidence density in different birth years (P>0.05). There was significant difference in the incidence density between 0-12 months old infants in different calendar years (Ptrend < 0.05). In this age group, the incidence density was the lowest in 2015 (69.41/100 000 person-years, 95%CI: 41.79-108.39), and the highest in 2019 (225.61/100 000 person-years, 95%CI: 186.10-271.03). There was no significant difference in the incidence density between 13-24 and 25-36 months old infants in different calendar years (P>0.05). CONCLUSION: The incidence density of epilepsy in 0-36 months old infants in Ningbo City from 2015 to 2019 was low as a whole, and there was no difference in age group, gender, and year of birth. The incidence density of 0-12 months old infants increased with the year.


Assuntos
Epilepsia , Pré-Escolar , Cidades , Epilepsia/epidemiologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
6.
Nature ; 515(7526): 245-8, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25391962

RESUMO

Films of iron selenide (FeSe) one unit cell thick grown on strontium titanate (SrTiO3 or STO) substrates have recently shown superconducting energy gaps opening at temperatures close to the boiling point of liquid nitrogen (77 kelvin), which is a record for the iron-based superconductors. The gap opening temperature usually sets the superconducting transition temperature Tc, as the gap signals the formation of Cooper pairs, the bound electron states responsible for superconductivity. To understand why Cooper pairs form at such high temperatures, we examine the role of the SrTiO3 substrate. Here we report high-resolution angle-resolved photoemission spectroscopy results that reveal an unexpected characteristic of the single-unit-cell FeSe/SrTiO3 system: shake-off bands suggesting the presence of bosonic modes, most probably oxygen optical phonons in SrTiO3 (refs 5, 6, 7), which couple to the FeSe electrons with only a small momentum transfer. Such interfacial coupling assists superconductivity in most channels, including those mediated by spin fluctuations. Our calculations suggest that this coupling is responsible for raising the superconducting gap opening temperature in single-unit-cell FeSe/SrTiO3.

7.
Zhonghua Zhong Liu Za Zhi ; 42(12): 1014-1019, 2020 Dec 23.
Artigo em Zh | MEDLINE | ID: mdl-33342157

RESUMO

Objective: To investigate the relationship between human papillomavirus (HPV) integration and prognosis of cervical cancer patients. Methods: The data of 82 patients with cervical cancer treated in the Radiotherapy Department of Peking Union Medical College Hospital from October 2004 to June 2012 were retrospectively analyzed.The patients were divided into poor prognosis group (recurrence or metastasis after surgery and adjuvant radiotherapy) and good prognosis group based on a propensity score matching strategy.The HPV integration of the two groups were detected by whole exome sequencing to determine whether the integration sites were located in the common fragile sites (CFSs). HPV integration and integration into CFSs were compared between the two groups. Results: Among the enrolled 82 patients, 37 were divided in poor survival group and 45 in good survival group. A total of 90 integration breakpoints were identified, 30 of them occurred in poor prognosis group and 60 occurred in good prognosis group. In the poor prognosis group, HPV integration occurred in 20 patients, 13 of them were inserted in CFSs of 11 patients, and the numbers in good prognosis group were 26, 17, 11, respectively. There were no significantly statistical differences in the number of HPV integration events (P=0.289), HPV integration patients (P=0.735), CFSs integration events (P=0.427), and CFSs integration patients (P=0.591) between the two groups. In poor prognosis group, more CFSs integration events occurred in patients with metastasis than those in patients with only local recurrence (9 vs 2, P=0.003). Conclusions: No significant differences are observed in HPV integration and HPV integration into CFSs between cervical cancer patients with different prognoses. HPV integration into CFSs may be associated with distant metastasis.


Assuntos
Alphapapillomavirus , Neoplasias do Colo do Útero , Integração Viral , Alphapapillomavirus/genética , Feminino , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/virologia , Integração Viral/genética
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(3): 527-534, 2020 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-32541988

RESUMO

OBJECTIVE: To estimate the prevalence rate of bone and joint injury in China and to describe the three-dimension distribution of the disease (area, time and people). METHODS: Based on a cross-sectional design, a retrospective study was conducted by using Chinese basic medical insurance database from January 1, 2013 to December 31, 2017 to analyze the epidemiological characteristics of bone and joint injury. The prevalence rate of bone and joint injury in each city was calculated, and then using meta-analyses to estimate the pooled prevalence of each area and the whole country. The pooled prevalence rates were compared among the different groups of populations, in terms of geographical area, time and population characteristics (age and gender). RESULTS: A total of 28 419 264 subjects were included in this study, including 705 793 patients with bone and joint injury. From 2013 to 2017, in Chinese basic medical insurance database, the overall prevalence rate of bone and joint injury was 141.5(95%CI: 90.4-203.7) per 10 000 population, and the prevalence rates of non-specific or polyarticular disease, knee disease, and shoulder disease were 101.6 (95%CI: 63.5-148.4)per 10 000 population, 22.5(95%CI:15.1-31.4)per 10 000 population and 10.9 (95%CI: 6.4-16.4)per 10 000 population. The prevalence rates varied across the areas, the highest rate was observed in North China, with the prevalence of 310.6 (95%CI: 12.6-989.7) per 10 000 population, and the lowest rate was observed in Southwest China, with the prevalence of 59.0 (95%CI: 37.5-85.2) per 10 000 population. The prevalence rate of bone and joint injury increased over the study period, from 111.1 (95%CI: 56.0-182.5)per 10 000 population in 2013 to 175.5 (95%CI: 116.8-245.5)per 10 000 population in 2017. The prevalence of bone and joint injury in the female population was 149.1 (95%CI: 94.2-215.9) per 10 000 population, which was higher than that of men [133.6(95%CI: 86.2-190.9) per 10 000 population]. The higher prevalence of knee disease, unspecified or polyarticular disease, and bone and joint injury were observed in people aged 60 years and older, while the prevalence of shoulder disease peaked in 40-59 years old people [20.6 (95%CI: 12.5-30.5) per 10 000 population]. CONCLUSION: This study reported a relative low prevalence of bone and joint injury in China from 2013 to 2017. The prevalence increased over the study period, and the highest prevalence rate was observed in North China. The prevalence rate showed differences among different groups of populations, and higher rates were observed in females and people aged 60 years and older.


Assuntos
Seguro Saúde , Adulto , China , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , População Urbana
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(7): 724-730, 2019 Jul 06.
Artigo em Zh | MEDLINE | ID: mdl-31288345

RESUMO

Objective: To identify post-marketing active surveillance systems for vaccine safety around the world and understand their features and mechanisms, in order to provide guidance for vaccine administration activities in China. Methods: Following the steps of scoping review, literature about active surveillance system for vaccine safety and published by 30 June 2018 were identified by searching electronic databases, including PubMed, Scopus, and Cochrane Library. Grey literature were also sought by exploring relevant websites. Identified literature were screened according to eligibility criteria, and informative data from included literature were then charted. Framework Synthesis and Thematic Analysis were performed to integrate the charted data. Results: 97 pieces of literature were included for review, and 11 active surveillance systems for vaccine safety were identified, mostly located in developed countries. These systems were constructed by 3 types of organizations: administration departments, academic or research institutions, and health care providers. Their data sources included immunization registries, electronic medical records, claims data, case reports of adverse events following immunization electronic questionnaires, and epidemiologic study data. According to their operation procedures, these systems were grouped into 4 modes of active surveillance: Data Linkage, Investigator Network, Automatic Follow-up System, Studies Consortium. Conclusion: Practice of active surveillance for vaccine safety greatly varies across countries, with different conditions and advantages. It is suggested that developing countries should choose suitable mode of active surveillance considering their local situations.


Assuntos
Vigilância de Produtos Comercializados/métodos , Vacinas/efeitos adversos , China , Países em Desenvolvimento , Humanos
10.
Zhonghua Zhong Liu Za Zhi ; 40(8): 614-618, 2018 Aug 23.
Artigo em Zh | MEDLINE | ID: mdl-30139033

RESUMO

Objective: To investigate the clinical features and prognosis of primitive neuroectodermal tumor (PNET). Methods: The clinical data of 99 patients with PNET from February 1, 1998 to February 1, 2017 were retrospectively analyzed. Univariate analysis was performed using Kaplan-Meier and Log rank test. Multiviate Cox regression was applied to analyzed independent prognostic factor for patient survival. Results: Among the 99 patients, 81 were peripheral PNET(pPNET) and 18 were central PNET (cPNET) . Biopsy was performed exclusively in 16 cases, with R0 resection in 61 cases, with R1 resection in 4 cases, and with R2 resection in 18 cases. Twelve patients underwent surgery only, nine had chemotherapy only, and one received radiotherapy only. There were 72 patients who had combined treatment including chemotherapy, and 48 patients had combined therapy including radiotherapy. The one-year, three-year and five-year overall survival(OS) rates of the 99 PNET patients were 79.2%, 63.9% and 56.1% respectively, and median OS time was 14.0 months. The one-year, three-year and five-year progression free survival (PFS) rates of these patients were 42.7%, 25.7% and 19.8% respectively, and median PFS time was 8.0 months. The univariate analysis revealed that lymph node metastasis, surgical resection, numbers of cycles of chemotherapy and radiotherapy dose were the main factors affecting the OS (all P<0.05). Gender, age, lymph node metastasis, staging, and chemotherapy cycles were related to PFS in PNET patients (P<0.05). Multivariate analysis showed that the degree of surgical resection, chemotherapy cycle, and radiotherapy dosage were independent influencing factors of OS in PNET patients (risk ratio=1.856, 0.398, and 0.408, respectively, all P<0.05), and gender was an independent factor influencing PFS in PNET patients (risk ratio=0.494, P<0.05). Conclusions: Comprehensive therapy is the main therapy for PNET patients. The surgical resection, cycles of chemotherapy and radiotherapy dosage are independent prognostic factors for patient's OS.


Assuntos
Neoplasias Encefálicas/mortalidade , Tumores Neuroectodérmicos Primitivos/mortalidade , Análise de Variância , Biópsia , Neoplasias Encefálicas/terapia , Terapia Combinada/métodos , Progressão da Doença , Intervalo Livre de Doença , Humanos , Tumores Neuroectodérmicos Primitivos/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
11.
Nat Mater ; 15(1): 27-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26524130

RESUMO

Topological Weyl semimetals (TWSs) represent a novel state of topological quantum matter which not only possesses Weyl fermions (massless chiral particles that can be viewed as magnetic monopoles in momentum space) in the bulk and unique Fermi arcs generated by topological surface states, but also exhibits appealing physical properties such as extremely large magnetoresistance and ultra-high carrier mobility. Here, by performing angle-resolved photoemission spectroscopy (ARPES) on NbP and TaP, we directly observed their band structures with characteristic Fermi arcs of TWSs. Furthermore, by systematically investigating NbP, TaP and TaAs from the same transition metal monopnictide family, we discovered their Fermiology evolution with spin-orbit coupling (SOC) strength. Our experimental findings not only reveal the mechanism to realize and fine-tune the electronic structures of TWSs, but also provide a rich material base for exploring many exotic physical phenomena (for example, chiral magnetic effects, negative magnetoresistance, and the quantum anomalous Hall effect) and novel future applications.

12.
J Chem Phys ; 146(12): 124307, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28388143

RESUMO

The proton mean kinetic energy, Ke(H), of water confined in nanocavities of beryl (Be3Al2Si6O18) at 5 K was obtained by simulating the partial vibrational density of states from density functional theory based first-principles calculations. The result, Ke(H) = 104.4 meV, is in remarkable agreement with the 5 K deep inelastic neutron scattering (DINS) measured value of 105 meV. This is in fact the first successful calculation that reproduces an anomalous DINS value regarding Ke(H) in nano-confined water. The calculation indicates that the vibrational states of the proton of the nano-confined water molecule distribute much differently than in ordinary H2O phases, most probably due to coupling with lattice modes of the hosting beryl nano-cage. These findings may be viewed as a promising step towards the resolution of the DINS controversial measurements on other H2O nano-confining systems, e.g., H2O confined in single and double walled carbon nanotubes.

13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 49(3): 446-450, 2017 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-28628145

RESUMO

OBJECTIVE: To explore the relationship between glycemic control and visceral adiposity index (VAI) among type 2 diabetes mellitus (T2DM) patients. METHODS: A community-based epidemiological field study for patients with T2DM aged ≥ 40 years was conducted in China.Every participant underwent physical examinations, biochemical tests of fasting glucose, glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and so on, and a questionnaire, including anthropometric characteristics, lifestyle, disease history, family history, and medication use. Those participants with HbA1c ≥7.0% were classified as the poorly controlled in our analysis of relationship between glycemic control and VAI. Anthropometric characteristics, lifestyle, and biochemical indexes of the participants were compared among the groups of different VAI levels. Logistic models were applied in multiple analysis adjusting for possible confounders. RESULTS: A total of 1 607 patients with T2DM were recruited in our analysis with a mean age of (59.4±8.1) years and an average T2DM duration of (7.0±6.4) years. Among them, 78.3% were on hypoglycemic therapy. The cutoff points of quartiles of VAI were calculated for the males and females, respectively. According to the ascending order of the quartiles of VAI, the participants were divided into four groups, i.e. Q1, Q2, Q3, and Q4. The poor glycemic control rate for these groups were 60.6%, 65.7%, 70.1%, and 71.0%, respectively (Trend χ2=12.20, P<0.001). After adjustment for age, gender, systolic blood pressure (SBP), diastolic blood pressure (DBP), LDL-C, smoking, cardio-cerebral vascular disease (CVD) history, hypoglycemic therapy, T2DM duration, and family history of diabetes, the Logistic regression models showed that the glycemic control rate was significantly associated with VAI levels among the patients with T2DM. Compared with the participants in group Q1, the ORs of poor glycemic control for those in groups Q2, Q3, and Q4 were 1.239 (95%CI 0.918 to 1.672), 1.513 (95%CI 1.117 to 2.050), and 1.535 (95%CI 1.128 to 2.088), respectively (trend P=0.003). With each quartile increase in VAI, the OR of poor glycemic control was 1.162 (95%CI 1.054 to 1.282). CONCLUSION: The glycemic control among the patients with T2DM is significantly associated with VAI. High level of VAI is an indicator of poor glycemic control.


Assuntos
Adiposidade , Glicemia , Diabetes Mellitus Tipo 2/fisiopatologia , Idoso , Pressão Sanguínea , China , HDL-Colesterol , LDL-Colesterol , Feminino , Hemoglobinas Glicadas , Humanos , Hipoglicemiantes , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal , Triglicerídeos
14.
Zhonghua Yu Fang Yi Xue Za Zhi ; 51(8): 670-674, 2017 Aug 06.
Artigo em Zh | MEDLINE | ID: mdl-28763913

RESUMO

Objective: To explore the psychological status and related factors in patients with precancerous of esophageal and gastric cardia in Linzhou of Henan. Methods: Clinical psycho-rating scale of Social Support Rating Scale (SSRS), Self-Rating Anxiety Scale (SAS, score ≥50 points with symptoms of anxiety) and Self-Rating Depression Scale (SDS, score ≥53 points with the symptoms of depression) were applied to survey life events and psychological status of subjects who aged 40-69 years old and participated in"The Early diagnosis and Early Treatment"program in Linzhou cancer hospital from July 2015 to Jan 2016. Patients with lower intraepithelial neoplasia or high-grade intraepithelial neoplasia were selected as precancerous lesions (n=118), and patients with normal grade were selected as healthy controls (n=210). Compare the differences of the scores between the two groups, and the logistic regression model was used to analyze the related factors of precancerous lesions and psychological status of the study subjects. Results: Precancerous lesions included esophageal (72 cases), gastric cardia (40 cases), esophageal and cardia dual source (6 cases); Precancerous lesions and healthy controls aged (57.17±7.71) and (53.12±7.99) years old, the difference was statistically significant (P<0.001). The anxiety and depression scale showed that the scores of SAS and SDS scores in the precancerous lesions were (37.18±10.01), (40.44±8.37) points, and (34.02±6.63), (38.49±8.73) points in control group, the difference was statistically significant (P=0.002, 0.032). While the social support total score (38.26±5.26), and subjective support score (24.08±3.83) and objective support score (7.50±1.89) in control group were all higher than those of precancerous group (36.80±6.18, 23.01±3.93, 6.93±1.57), and the difference were statistically significant (P=0.024, 0.016, 0.004). In addition, the Logistic analysis showed that subjects with low objective social support, subjective social support and anxiety symptoms were more likely to develop precancerous lesions, and the OR were 0.81, 0.72 and 1.05, respectively (P=0.028, 0.005, 0.009). Conclusion: Social support, anxiety and depression status may be related to the occurrence and development of esophageal and gastric cardia precancerous lesions.


Assuntos
Cárdia , Neoplasias Esofágicas/psicologia , Lesões Pré-Cancerosas/psicologia , Neoplasias Gástricas/psicologia , Adulto , Idoso , Ansiedade/epidemiologia , China/epidemiologia , Depressão/epidemiologia , Neoplasias Esofágicas/epidemiologia , Humanos , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/epidemiologia , Apoio Social , Neoplasias Gástricas/epidemiologia , Inquéritos e Questionários
15.
Phys Chem Chem Phys ; 18(25): 16870-81, 2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27282515

RESUMO

Using first-principles calculations accompanied by the transition state theory and an 8-frequency model, we present a comprehensive investigation of the diffusion coefficients of substitutional alloying elements X in dilute α-Ti alloys, where X denotes Al, V, Nb, Ta, Mo, Zr, and Sn. The alloying elements Mo and Al exhibit a maximum and a minimum diffusion rate in dilute α-Ti alloys, respectively. It is found that the nearest-neighbor solute-vacancy binding energies and activation energies are roughly inversely proportional to the volume changes induced by solute atoms. There are two exceptions to this trend: Al and Mo. Besides the physical effect (i.e., solute size), two other key factors governing solute diffusion in dilute α-Ti are clarified: the chemical bonding characteristics and vibrational features of X-Ti pairs. It verifies that the ultrafast diffusivity of Mo arises from the interactions with Ti atoms by metallic bonds and its low-frequency contributions to lattice vibration, while the more covalent bonding nature and the high-frequency contributions to the lattice vibration of Al lead to its ultraslow diffusivity. In addition, the correlation effects of diffusion coefficients are non-negligible for the large solutes Ta, Nb, and Zr, in which the direct solute-vacancy migration barriers are much smaller than the solvent-vacancy migration barriers.

16.
J Chem Phys ; 144(5): 054302, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26851916

RESUMO

The mean atomic kinetic energies of the proton, Ke(H), and of the deuteron, Ke(D), were calculated in moderate and strongly hydrogen bonded (HB) systems, such as the ferro-electric crystals of the KDP type (XH2PO4, X = K, Cs, Rb, Tl), the DKDP (XD2PO4, X = K, Cs, Rb) type, and the X3H(SO4)2 superprotonic conductors (X = K, Rb). All calculations utilized the simulated partial phonon density of states, deduced from density functional theory based first-principle calculations and from empirical lattice dynamics simulations in which the Coulomb, short range, covalent, and van der Waals interactions were accounted for. The presently calculated Ke(H) values for the two systems were found to be in excellent agreement with published values obtained by deep inelastic neutron scattering measurements carried out using the VESUVIO instrument of the Rutherford Laboratory, UK. The Ke(H) values of the M3H(SO4)2 compounds, in which the hydrogen bonds are centro-symmetric, are much lower than those of the KDP type crystals, in direct consistency with the oxygen-oxygen distance ROO, being a measure of the HB strength.

17.
Artigo em Zh | MEDLINE | ID: mdl-27682489

RESUMO

Objective: To investigate the influencing factors for trauma-induced tibial infection in underground coal mine. Methods: A retrospective analysis was performed for the clinical data of 1 090 patients with tibial fracture complicated by bone infection who were injured in underground coal mine and admitted to our hospital from January 1995 to August 2015, including the type of trauma, injured parts, severity, and treatment outcome. The association between risk factors and infection was analyzed. Results: Among the 1 090 patients, 357 had the clinical manifestations of acute and chronic bone infection, 219 had red and swollen legs with heat pain, and 138 experienced skin necrosis, rupture, and discharge of pus. The incidence rates of tibial infection from 1995 to 2001, from 2002 to 2008, and from 2009 to 2015 were 31%, 26.9%, and 20.2%, respectively. The incidence rate of bone infection in the proximal segment of the tibia was significantly higher than that in the middle and distal segments (42.1% vs 18.9%/27.1%, P<0.01) . As for patients with different types of trauma (Gustilo typing) , the patients with type III fracture had a significantly higher incidence rate of bone infection than those with type I/II infection (52.8% vs 21.8%/24.6%, P<0.01) . The incidence rates of bone infection after bone traction, internal fixation with steel plates, fixation with external fixator, and fixation with intramedullary nail were 20.7%, 43.5%, 21.4%, and 26.1%, respectively, suggesting that internal fixation with steel plates had a significantly higher incidence rate of bone infection than other fixation methods (P<0.01) . The multivariate logistic regression analysis showed that the position of tibial fracture and type of fracture were independent risk factors for bone infection. Conclusion: There is a high incidence rate of trauma-induced tibial infection in workers in underground coal mine. The position of tibial fracture and type of fracture are independent risk factors for bone infection. Vacuum sealing drainage and Ilizarov technique can achieve a satisfactory therapeutic effect.


Assuntos
Mineração , Fraturas da Tíbia , Infecção dos Ferimentos , Carvão Mineral , Fixadores Externos , Fixação Intramedular de Fraturas , Humanos , Estudos Retrospectivos , Resultado do Tratamento
18.
Nat Mater ; 13(7): 677-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24859642

RESUMO

Three-dimensional (3D) topological Dirac semimetals (TDSs) are a recently proposed state of quantum matter that have attracted increasing attention in physics and materials science. A 3D TDS is not only a bulk analogue of graphene; it also exhibits non-trivial topology in its electronic structure that shares similarities with topological insulators. Moreover, a TDS can potentially be driven into other exotic phases (such as Weyl semimetals, axion insulators and topological superconductors), making it a unique parent compound for the study of these states and the phase transitions between them. Here, by performing angle-resolved photoemission spectroscopy, we directly observe a pair of 3D Dirac fermions in Cd3As2, proving that it is a model 3D TDS. Compared with other 3D TDSs, for example, ß-cristobalite BiO2 (ref. 3) and Na3Bi (refs 4, 5), Cd3As2 is stable and has much higher Fermi velocities. Furthermore, by in situ doping we have been able to tune its Fermi energy, making it a flexible platform for exploring exotic physical phenomena.

19.
Phys Rev Lett ; 114(3): 037002, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25659015

RESUMO

We report findings of strong anomalies in both mutual inductance and inelastic Raman spectroscopy measurements of single-unit-cell FeSe film grown on Nb-doped SrTiO3, which occur near the temperature where the superconductinglike energy gap opens. Analysis suggests that the anomaly is associated with a broadened ferroelectric transition in a thin layer near the FeSe/SrTiO3 interface. The coincidence of the ferroelectric transition and gap-opening temperatures adds credence to the central role played by the film-substrate interaction on the strong Cooper pairing in this system. We discuss scenarios that could explain such a coincidence.

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