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1.
Phys Chem Chem Phys ; 26(8): 7083-7089, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38345644

RESUMEN

The application of in situ Raman spectroscopy under multiple fields is widely recognized as an effective approach for investigating the physical mechanism of phase transitions in ferroelectrics, because it can directly provide the detailed information about the vibration evolution of various phonon modes within lattices, such as bond stretching and rotation. Based on this technique, our work aims to thoroughly probe the dynamics of phase transitions in traditional ferroelectric potassium sodium niobate [(K,Na)NbO3, KNN] under external fields, by analyzing the in situ dependence of wavenumber and intensity of phonon modes under the varying temperature and electric fields. The results indicate that different vibration modes respectively relating to the A-site ions and NbO6 octahedra in KNN exhibit distinct and abrupt distortion behavior during the orthorhombic-tetragonal and tetragonal-cubic transitions. Moreover, a certain degree of distortion can still be observed in the cubic phase above the Curie temperature. With an applied electric field, KNN presents quite different electrostriction in orthorhombic and tetragonal phases. Particularly, more than one kind of phonon mode undergoes non-linear variations under the varying electric fields, accompanied by the mutations at some fixed fields. These findings will be conducive to further understanding the phase transition mechanism in KNN from the perspective of phonon evolution. Simultaneously, it will also give crucial guidance for the design and development of KNN-based ferroelectrics as well as functional devices.

2.
Zhonghua Nei Ke Za Zhi ; 61(9): 1023-1030, 2022 Sep 01.
Artículo en Chino | MEDLINE | ID: mdl-36008295

RESUMEN

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ2 test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.


Asunto(s)
Carcinoma de Células Pequeñas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Histiocitoma Fibroso Maligno , Melanoma , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Humanos , Masculino
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(12): 2059-2065, 2020 Dec 10.
Artículo en Chino | MEDLINE | ID: mdl-33378817

RESUMEN

Objective: To investigate the relationships between vitamin D nutritional status and the risks of cardiometabolic abnormities in children. Methods: Data were obtained from the School-based Cardiovascular and Bone Health Promotion Program. In 2017, a total of 15 391 children aged 6-16 years in Beijing were selected by using a stratified cluster sampling method in the baseline survey. A Follow-up investigation was conducted in 2019. Log-binomial regression was used to analyze the relationships between baseline vitamin D nutritional status and the risks of cardiometabolic abnormities (obesity, hypertension, hyperglycemia, and dyslipidemia). Results: A total of 10 482 participants were involved in the study. The average vitamin D level was (35.6 ± 12.0) nmol/L, and the deficiency rate was 35.1%. The 2-year cumulative incidence rates of obesity, hypertension, hyperglycemia, high TC, high LDL-C, low HDL-C, high TG, and high non-HDL-C were 4.3%, 10.8%, 8.5%, 3.1%, 2.5%, 3.4%, 2.5%, and 3.9% respectively. After the adjustment of potential confounding factors, children with vitamin D inadequacy or deficiency had higher risks of high TC [RR (95%CI): inadequacy, 2.06 (1.19-3.58); deficiency, 2.80 (1.61-4.89)], high LDL-C [RR (95%CI): inadequacy, 1.67 (1.02-2.73); deficiency, 1.99 (1.19-3.33)], and high non-HDL-C [RR (95%CI): inadequacy, 2.00 (1.26-3.17); deficiency, 2.45 (1.53-3.92)] compared with children with adequate vitamin D, and the risks of them increased with the decrease of vitamin D level (trend P<0.05). The gender-stratified analysis showed that vitamin D deficiency was remained associated with high TC [RR (95%CI): boy, 2.64 (1.19-5.87); girl, 3.13 (1.43-6.83)] and high non-HDL-C [RR (95%CI): boy, 2.58(1.40-4.77); girl, 2.31 (1.10-4.84)]. Conclusions: The risks of abnormal TC, LDL-C, and non-HDL-C were inversely associated with vitamin D level. Maintenance of adequate vitamin D status in children may contribute to the early prevention of cardiovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares , Deficiencia de Vitamina D , Adolescente , Beijing/epidemiología , Enfermedades Cardiovasculares/epidemiología , Niño , Femenino , Humanos , Masculino , Estado Nutricional , Estudios Prospectivos , Factores de Riesgo , Vitamina D/sangre , Deficiencia de Vitamina D/epidemiología
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(12): 2066-2071, 2020 Dec 10.
Artículo en Chino | MEDLINE | ID: mdl-33378818

RESUMEN

Objective: To explore the screening effect of obesity assessed by body fat indicators on persistent dyslipidemia among children. Methods: Data were obtained from the baseline and follow-up survey of 'School-based Cardiovascular and Bone Health Promotion Program.' BMI, fat mass index (FMI), and fat mass percentage (FMP) were used to define obesity. Dyslipidemia, diagnosed both in the baseline and a follow-up survey, was defined as persistent dyslipidemia. The area under the receiver operating characteristic curve (AUC) was used to compare the predictive capabilities of obesity defined by different indicators on persistent dyslipidemia. Results: A total of 10 783 children (boys accounted for 49.6%) were included in the analysis, with the average age as (10.9±3.3) years old. The detection rates of persistent high TC, high LDL-C, low HDL-C, high TG, and high non-HDL-C were 1.3%, 1.2%, 4.3%, 1.3%, and 0.8%, respectively. In boys, the capabilities of FMI- and FMP-defined obesity in the prediction of persistent high LDL-C [FMI: AUC=0.626 (95%CI: 0.558-0.694), P=0.024; FMP: AUC=0.642 (95%CI: 0.574-0.710), P=0.004] and high non-HDL-C [FMI: AUC=0.637 (95%CI: 0.584-0.689), P=0.017; FMP: AUC=0.641 (95%CI: 0.588- 0.693), P=0.018] were significantly higher than BMI-defined obesity. Besides, obese boys defined by FMI had the stronger capability in predicting persistent low HDL-C than that defined by BMI [AUC=0.784 (95%CI: 0.742-0.826) vs. 0.750 (95%CI: 0.726-0.773), P=0.047]. In girls, the capabilities of FMI- and FMP-defined obesity in the prediction of persistent dyslipidemia were not statistically different from BMI. Conclusions: The obesity assessed by body fat performed better in predicting persistent high LDL-C, low HDL-C, and high non-HDL-C than that assessed by BMI among boys, which can be further applied to cardiovascular disease prevention.


Asunto(s)
Tejido Adiposo , Dislipidemias , Tamizaje Masivo , Obesidad Infantil , Adolescente , Niño , Dislipidemias/diagnóstico , Dislipidemias/epidemiología , Femenino , Humanos , Masculino , Tamizaje Masivo/métodos , Obesidad Infantil/diagnóstico , Obesidad Infantil/epidemiología
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(1): 62-67, 2020 Jan 10.
Artículo en Chino | MEDLINE | ID: mdl-32062944

RESUMEN

Objective: To compare the power of dyslipidemia diagnosis by different sets of cut points in the prediction of cardiovascular metabolic risk factors and identify the appropriate cut points for the diagnosis of dyslipidemia in children and adolescents in China. Methods: Data were obtained from the baseline survey of 'School-based Cardiovascular and Bone Health Promotion Program' in Beijing in 2017. Dyslipidemia was diagnosed by using two set of cut points. Receiver operating characteristic curve analysis was conducted to assess the power of dyslipidemia diagnosis by the two set of cut points to predict the prevalence of hypertension, obesity, high fat mass percentage and impaired fasting glucose. Results: A total of 14 390 children and adolescents were in included in the study. The prevalence rates of high TC, high LDL-C, low HDL-C, and high TG in the participants were 2.7%, 2.7%, 14.4%, and 3.7% according to 'Chinese Reference Standard', and 5.0%, 3.7%, 13.3%, and 3.5% according to 'China Expert Consensus'. Low HDL-C and high TG defined by the 'Chinese Reference Standard' had better performance for the prediction of high fat mass percentage and obesity in boys, but worse performance in girls (P<0.001). Conclusions: Using 'China Reference Standard' can increase the true positive rate in the prediction of obesity or high fat mass percentage in boys, and reduce the false positive rate in girls. The cut points for the diagnosis of dyslipidemia in Chinese children and adolescents need to be further validated by using national representative sample and in longitudinal study.


Asunto(s)
Dislipidemias , Adolescente , Beijing , Niño , China , Dislipidemias/complicaciones , Dislipidemias/diagnóstico , Femenino , Humanos , Estudios Longitudinales , Masculino , Obesidad/complicaciones , Prevalencia , Valores de Referencia , Factores de Riesgo
7.
RSC Adv ; 10(9): 5502-5506, 2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35498292

RESUMEN

Ionomer in the catalyst layer provides an ion transport channel which is essential for many electrochemical devices. As the ionomer and electrochemical catalyst are packed together in the catalyst layer, it is difficult to have a clear image of the ionomer distribution in the catalyst layer and how the ionomer is in contact with Pt or carbon. A highly dispersed catalyst was deposited on the TEM SiN grid directly using the same (ultrasonic spray) or a similar way as the catalyst was deposited on the membrane. By analyzing the distribution of various elements (C, F, S, Pt etc.), we found that the ionomer may coexist in the catalyst layer in three ways: ionomer covered Pt particles due to the relatively strong interaction between Pt and the ionomer; ionomer covered C particles; packed free ionomer in between the aggregated catalyst particles. The results show that the ionomer is prone to covering the surface of Pt particles as further evidenced by the accelerated degradation test (ADT).

8.
Sci Adv ; 5(3): eaav9075, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30989106

RESUMEN

Contemporary models of intrafibrillar mineralization mechanisms are established using collagen fibrils as templates without considering the contribution from collagen-bound apatite nucleation inhibitors. However, collagen matrices destined for mineralization in vertebrates contain bound matrix proteins for intrafibrillar mineralization. Negatively charged, high-molecular weight polycarboxylic acid is cross-linked to reconstituted collagen to create a model for examining the contribution of collagen-ligand interaction to intrafibrillar mineralization. Cryogenic electron microscopy and molecular dynamics simulation show that, after cross-linking to collagen, the bound polyelectrolyte caches prenucleation cluster singlets into chain-like aggregates along the fibrillar surface to increase the pool of mineralization precursors available for intrafibrillar mineralization. Higher-quality mineralized scaffolds with better biomechanical properties are achieved compared with mineralization of unmodified scaffolds in polyelectrolyte-stabilized mineralization solution. Collagen-ligand interaction provides insights on the genesis of heterogeneously mineralized tissues and the potential causes of ectopic calcification in nonmineralized body tissues.


Asunto(s)
Materiales Biomiméticos/metabolismo , Calcificación Fisiológica , Colágeno/metabolismo , Ligandos , Biomimética/métodos , Matriz Extracelular/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Microscopía Electrónica/métodos , Minerales/metabolismo , Modelos Moleculares , Simulación de Dinámica Molecular , Polielectrolitos/metabolismo , Andamios del Tejido
9.
Phys Chem Chem Phys ; 20(23): 16067-16076, 2018 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-29855000

RESUMEN

In this work, the structural, electronic and optical properties of germanene and ZnSe substrate nanocomposites have been investigated using first-principles calculations. We found that the large direct-gap ZnSe semiconductors and zero-gap germanene form a typical orbital hybridization heterostructure with a strong binding energy, which shows a moderate direct band gap of 0.503 eV in the most stable pattern. Furthermore, the heterostructure undergoes semiconductor-to-metal band gap transition when subjected to external out-of-plane electric field. We also found that applying external strain and compressing the interlayer distance are two simple ways of tuning the electronic structure. An unexpected indirect-direct band gap transition is also observed in the AAII pattern via adjusting the interlayer distance. Quite interestingly, the calculated results exhibit that the germanene/ZnSe heterobilayer structure has perfect optical absorption in the solar spectrum as well as the infrared and UV light zones, which is superior to that of the individual ZnSe substrate and germanene. The staggered interfacial gap and tunability of the energy band structure via interlayer distance and external electric field and strain thus make the germanene/ZnSe heterostructure a promising candidate for field effect transistors (FETs) and nanoelectronic applications.

10.
Phys Chem Chem Phys ; 20(19): 13616-13622, 2018 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-29737340

RESUMEN

Density-functional theory calculations have been performed to systematically investigate the behaviors of solute atoms in 7000 series Al-Zn-Mg based alloys. It is found that solute atoms Mg and Zn are likely to segregate to the Σ5(210)[001] tilt Al GB. The bonding environment and interface cohesion will be affected to different degrees. Also, for GPI(100) our calculations indicate that a Zn/Mg/Zn sandwich configuration in the Al matrix (100) planes is energetically favorable. However, for GPII(111) the disordered structure turns out to be the most stable one. It mainly results from strong 3d-3s hybridization interactions between Zn and Mg atoms. Furthermore, the properties of the metastable phase η' and the equilibrium phase η have also been addressed. The present study provides valuable insight for developing Al alloys with superior performance.

11.
Zhonghua Yi Xue Za Zhi ; 97(17): 1312-1315, 2017 May 09.
Artículo en Chino | MEDLINE | ID: mdl-28482432

RESUMEN

Objective: To investigate the value of duodenal bulb ultrasonic anatomy locating method quickly confirm nasointestinal tube placed below pylorus in critically ill patients. Methods: A total of 56 critically ill patients with nasointestinal tube posting surgery by blindly inserting method were collected from March 1 st, 2016 to August 1 st, 2016 in the Department of Critical Care Medicine of Zhejiang Provincial People's Hospital.In these patients, the duodenal bulbs were rapidly detected and located by ultrasonic anatomy locating method and at the same time observed whether nasointestinal tube echogram were in them or not. If nasointestinal tube echogram was observed in duodenal bulbs that meant nasointestinal tube placed below pylorus successfully. If disturbed by ultrasound artifacts or other reasons, injected gas into the nasointestinal tube could help to confirm when hyperechoic strip emerged. Gastrointestinal decompression or gastrointestinal motion promoting drug could help to reduce the interference of abdominal cavity or bowel gas if necessary. The results were compared with the abdominal X examination to vertify the accuracy of this method, and at the same time recorded its total time-consuming and its related complications. Results: The duodenal bulbs were rapidly located by ultrasonic anatomy locating method in 53 cases(94.6%) time-consuming(42±23)s. Nasointestinal tubes observed in duodenal bulb were confirmed to be placed below pylorus successfully in 52 cases(92.9%)time-consuming(140±94)s.There were no obvious complications in all patients. Conclusion: Duodenal bulb ultrasonic anatomy locating method is a safe, simple and convenient method with high accuracy that can quickly confirm whether nasointestinal tube placed below pylorus in critically ill patients or not.


Asunto(s)
Enfermedad Crítica , Intubación Gastrointestinal , Píloro/anatomía & histología , Cuidados Críticos , Nutrición Enteral , Humanos , Píloro/diagnóstico por imagen , Ultrasonografía
12.
Genet Mol Res ; 16(2)2017 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-28407177

RESUMEN

Porcine ear size is an important characteristic for distinguishing among pig breeds. In a previous genome-wide association study of porcine ear size, LEM domain-containing 3 (LEMD3), methionine sulfoxide reductase B3 (MSRB3), high mobility group AT-hook 2 (HMGA2), and Wnt inhibitory factor 1 (WIF1) were implicated as important candidate genes for ear size. This study investigated the expression levels of four candidate genes for ear size in Erhualian and Large White pigs. Ten Erhualian pigs with large ears and eight Large White pigs with small ears at 60 days of age were examined. The mRNA expression levels of the four candidate genes were quantified by real-time polymerase chain reaction. WIF1 mRNA expression was significantly higher in Large White than in Erhualian pigs (P < 0.05), whereas the expression levels of the other three genes were not significantly different between the two breeds. The protein expression levels of the four genes were analyzed using western blot. WIF1 protein expression was significantly higher in Large White than in Erhualian pigs (P < 0.01), whereas MSRB3 protein expression was significantly higher in Erhualian than in Large White pigs (P < 0.05). There were no significant differences between the two breeds in residual protein expression. These results suggest that WIF1 is the main causal gene for ear size in pigs.


Asunto(s)
Oído/crecimiento & desarrollo , Sitios de Carácter Cuantitativo , Porcinos/genética , Animales , Animales Endogámicos , Proteínas de la Matriz Extracelular/genética , Proteínas de la Matriz Extracelular/metabolismo , Perfilación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Metionina Sulfóxido Reductasas/genética , Metionina Sulfóxido Reductasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
13.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 35(10): 754-758, 2017 Oct 20.
Artículo en Chino | MEDLINE | ID: mdl-29294549

RESUMEN

Objective: To investigate the current status of job burnout in clinical nurses in a grade A tertiary hospitalin Shaoxing,China and related influencing factors. Methods: In October 2016, the Nursing Burnout Scale (NBS)was used for the investigation of 304 clinical nurses in a grade A tertiary hospital.The contents of the investigation included general data(including age,education background,working years,marital status, frequency of night shifts,professional title, and way of employment), characteristics of working environment,burnout, personality characteristics,coping strategy,and psychosomatic symptoms.SPSS 18.0 was used to conduct Pearson correlation analysis of the scores of each dimension of NBS. A multivariate regression analysis was performed with the demographic features of clinical nurses as the independent variable and the scores of each dimension of NBS as the dependent variable. Results: Among the clinical nurses in this grade A tertiary hospital, the incidence rate of severe burnout was 74%.The Pearson correlation analysis showed that burnout,pessimistic personality,negative coping,and psychosomatic symptoms were positively correlated with working environment(r=0.530,0.316,0.116,and 0.502); pessimistic personality and psychosomatic symptoms were positively correlated with burnout(r=0.618 and 0.675); psychosomatic symptoms were positively correlated withpessimistic personality(r=0.540); negative coping was negatively correlated with pessimistic personality(r=-0.145).The multivariate linear regression analysis showed that department(Department of Internal Medicine or Department of Surgery,B=-0.364 and -0.428)and frequency of night shifts(<6 times/month and 6-10 times/month,B=0.199 and 0.256)were influencing factors for the score of working environment; department(Department of Internal Medicine or Department of Surgery, B=-0.350 and -0.360)was an influencing factor for the score of burnout; 1-3 working years(B=-0.238)was an influencing factor for the score of pessimistic personality; married state,1-3 working years,and department (Department of Internal Medicine or Department of Surgery)were influencing factors for the score of psychosomatic symptoms(B=0.263,-0.301,-0.322,and -0.391). Conclusion: There is a high incidence rate of job burnout among clinical nurses in this grade A tertiary hospital,which is associated with burnout,working environment, pessimistic personality,and psychosomatic symptoms.Marital status,working years,department,and frequency of night shifts are major influencing factors for job burnout.


Asunto(s)
Agotamiento Profesional/psicología , Satisfacción en el Trabajo , Personal de Enfermería en Hospital/psicología , Estrés Psicológico , Tolerancia al Trabajo Programado , Adaptación Psicológica , China , Humanos , Personal de Enfermería en Hospital/estadística & datos numéricos , Personalidad , Encuestas y Cuestionarios , Centros de Atención Terciaria
14.
Genet Mol Res ; 15(3)2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27525933

RESUMEN

Mitogen-activated protein kinase kinase kinase 5 (MAP3K5) is essential for apoptosis, proliferation, differentiation, and immune responses, and is a candidate marker for residual feed intake (RFI) in pig. We cloned the full-length cDNA sequence of porcine MAP3K5 by rapid-amplification of cDNA ends. The 5451-bp gene contains a 5'-untranslated region (UTR) (718 bp), a coding region (3738 bp), and a 3'-UTR (995 bp), and encodes a peptide of 1245 amino acids, which shares 97, 99, 97, 93, 91, and 84% sequence identity with cattle, sheep, human, mouse, chicken, and zebrafish MAP3K5, respectively. The deduced MAP3K5 protein sequence contains two conserved domains: a DUF4071 domain and a protein kinase domain. Phylogenetic analysis showed that porcine MAP3K5 forms a separate branch to vicugna and camel MAP3K5. Tissue expression analysis using real-time quantitative polymerase chain reaction (qRT-PCR) revealed that MAP3K5 was expressed in the heart, liver, spleen, lung, kidney, muscle, fat, pancrea, ileum, and stomach tissues. Copy number variation was detected for porcine MAP3K5 and validated by qRT-PCR. Furthermore, a significant increase in average copy number was detected in the low RFI group when compared to the high RFI group in a Duroc pig population. These results provide useful information regarding the influence of MAP3K5 on RFI in pigs.


Asunto(s)
MAP Quinasa Quinasa Quinasa 5/genética , Sus scrofa/genética , Secuencia de Aminoácidos , Animales , Dominio Catalítico , Clonación Molecular , Variaciones en el Número de Copia de ADN , Dosificación de Gen , Expresión Génica , Interacciones Hidrofóbicas e Hidrofílicas , MAP Quinasa Quinasa Quinasa 5/química , MAP Quinasa Quinasa Quinasa 5/metabolismo , Modelos Moleculares , Especificidad de Órganos , Filogenia , Conformación Proteica en Hélice alfa , Sus scrofa/metabolismo
15.
Phys Chem Chem Phys ; 18(17): 12029-34, 2016 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-27067113

RESUMEN

The quaternary compound semiconductor Cu2ZnSnS4 (CZTS) is a promising photovoltaic absorber material for thin-film solar cell applications. Density-functional theory calculations have been performed to investigate the structural and electronic properties of the CdS/CZTS heterointerfaces in CZTS-based cells. We find that CdS favors epitaxial growth on the Cu-Zn plane of CZTS along the direction of [100], which can eliminate the effects of the wrong bonds at the interfaces and enhance the energetic barrier for charge carrier recombination across the interfaces with an increased band gap. The band alignment is calculated for the epitaxial CZTS/CdS heterointerface by employing the HSE06 functional and the results show a type-II band alignment with VBO and CBO values of 0.95 eV and -0.05 eV, respectively. Also, the experimental phenomenon of Zn segregation at CdS/CZTS interfaces is corroborated. Zn segregation can enhance the stability of the heterointerfaces, but damage the solar cell performance by decreasing the band gap when the Zn concentration is sufficiently high. We show that besides the defects and undesired phases in CZTS, the heterointerfaces between the absorption layers (CZTS) and the buffer layer (CdS) can also be an important factor that affects the performance of CZTS cells. The present work provides a theoretical base for engineering the heterointerfaces and achieving better performance of CZTS-based solar cells.

16.
Zhonghua Zhong Liu Za Zhi ; 38(3): 228-31, 2016 Mar 23.
Artículo en Chino | MEDLINE | ID: mdl-26988831

RESUMEN

OBJECTIVE: To study the feasibility and therapeutic effect of the application of (125)I seeds combined with biliary stent implantation on the treatment of malignant obstructive jaundice. METHODS: Fifty patients with malignant obstructive jaundice treated from September 2010 to February 2013 in Yantai Yuhuangding Hospital were included in this study. Among them, 24 patients received biliary stent implantation combined with (125)I seeds intraluminal brachytherapy as experimental group, and 26 were treated by biliary stent implantation as control group.The total bilirubin, direct bilirubin and tumor markers (CA-199, CA-242, CEA) before and after surgery, the biliary stent patency status was assessed, and the survival time was evaluated. RESULTS: The 24 patients in experimental group were implanted with 30 (125)I seeds successfully in a total of 450 seeds. Jaundice was improved greatly in both groups. The CA-199 and CA-242 after treatment in the experimental group were significantly decreased than that before treatment (P=0.003 and P=0.004). CEA was also decreased, but showed no statistical significance (P>0.05). There were no significant improvement comparing the CA-199, CA-242 and CEA before and 2 months after surgery in the control group (P>0.05). The rate of biliary stent patency was 83.3% (20/24) in the experimental group and 57.7% (15/26) in the control group (P=0.048). The mean biliary stent patency time in the experimental group was 9.84 months (range 1-15.5 months). The mean biliary stent patency time in the control group was 5.57 months (range 0.8-9 months). There was a significant difference between the two groups (P=0.018). The median survival time was 10.2 months in the experimental group and 5.4 months in the control group (P<0.05). CONCLUSION: (125)I seeds combined with biliary stent implantation can inhibit the proliferation of vascular endothelial cells and the growth of tumor effectively, and can prolong the biliary stent patency time and the survival time obviously for patients with malignant obstructive jaundice, therefore, is a safe and effective treatment in this malignancy.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Yodo/uso terapéutico , Ictericia Obstructiva/terapia , Stents , Antígenos de Carbohidratos Asociados a Tumores/sangre , Bilirrubina/sangre , Antígeno CA-19-9/sangre , Antígeno Carcinoembrionario/análisis , Estudios de Casos y Controles , Terapia Combinada/métodos , Estudios de Factibilidad , Humanos , Ictericia Obstructiva/sangre , Ictericia Obstructiva/mortalidad , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
17.
Genet Mol Res ; 15(1)2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26909946

RESUMEN

The signal peptide CUB EGF-like domain-containing protein 3 (SCUBE3) gene is a member of SCUBE gene family and plays important roles in bone cell biology and the determination of limb bone length. In this study, the full-length transcript of porcine SCUBE3 was cloned using reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends. The full-length sequence of porcine SCUBE3 cDNA was 4131 base pairs and included 21 exons. The SCUBE3 gene contained a 2895-base pair open reading frame that encoded a peptide of 965 amino acids. Comparison of the deduced amino acid sequences of porcine SCUBE3 with those of human, mouse, zebrafish, and rat showed 96, 95, 73, and 95% identities, respectively. Porcine SCUBE3 mRNA expression levels were highest in the backfat, bone marrow, and cartilage tissues. Copy number variation was detected in porcine SCUBE3 and validated by real-time quantitative polymerase chain reaction. Different copy number variations were present in randomly selected individuals and may, therefore, be a good marker for identifying phenotypic traits. Our findings provide a basis for further investigation of the functions and regulatory mechanisms of SCUBE3 in pigs.


Asunto(s)
Clonación Molecular , Variaciones en el Número de Copia de ADN , Expresión Génica , Receptores de Superficie Celular/genética , Sus scrofa/metabolismo , Animales , Médula Ósea/metabolismo , Cartílago/metabolismo , Especificidad de Órganos , Filogenia , ARN Mensajero , Receptores de Superficie Celular/química , Receptores de Superficie Celular/metabolismo , Sus scrofa/genética
18.
Child Care Health Dev ; 38(5): 723-31, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21902710

RESUMEN

BACKGROUND: Many rural children in China have been experiencing life without fathers since the 1990s, when their fathers left the rural areas for the urban areas to find a job that would allow them to continue to support their family. However, to date, knowledge and understanding of the effects of the absence of fathers and timing of separation on the mental health of adolescents are limited. METHODS: A total of 2233 students, ranging in age from 11 to 23 years, from five provinces of China, including 1024 adolescents who experienced the absence of their fathers, were recruited for this study. The data were collected using State-Trait Anxiety Inventory and Rosenberg Self-Esteem Scale, which were self-report questionnaires. RESULTS: Findings from a structured questionnaire showed that the subjects who experienced life without fathers have increased state-anxiety (t=-5.80, P < 0.001) and lower self-esteem (t= 39.54, P < 0.001) when compared with other subjects, and the above results could be influenced by gender and grade. A limited effect of the timing of separation was found on the mental health of students whose fathers were absent. A significant timing group effect existed for state-anxiety scores [F(3,992) = 2.26, P= 0.05], and post test also revealed that the self-esteem of female scores in the 0-2 timing group was higher than other timing group's [F(3,992) = 4.58, P= 0.004]. CONCLUSION: The influence of the absence of fathers on the anxiety and self-esteem of adolescents seems to be more serious than our expectation, and the influence will be different according to the timing of father absence.


Asunto(s)
Ansiedad de Separación/etiología , Emigración e Inmigración , Padre/psicología , Autoimagen , Adolescente , Análisis de Varianza , Niño , China , Estudios Transversales , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
19.
Phys Chem Chem Phys ; 14(4): 1529-34, 2012 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-22159029

RESUMEN

We present ab initio calculations of the melting temperatures for bcc metals Nb, Ta and W. The calculations combine phase coexistence molecular dynamics (MD) simulations using classical embedded-atom method potentials and ab initio density functional theory free energy corrections. The calculated melting temperatures for Nb, Ta and W are, respectively, within 3%, 4%, and 7% of the experimental values. We compare the melting temperatures to those obtained from direct ab initio molecular dynamics simulations and see if they are in excellent agreement with each other. The small remaining discrepancies with experiment are thus likely due to inherent limitations associated with exchange-correlation energy approximations within density-functional theory.

20.
J Int Med Res ; 38(4): 1259-65, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20925998

RESUMEN

Transcatheter arterial chemoembolization (TACE) with iodized oil and anticancer agents is widely used for hepatocellular carcinoma (HCC) treatment. To assess C-arm angiographic computed tomography (CCT) for detecting iodized oil retention during TACE, CCT images were obtained of 40 tumours (24 HCC patients). The primary CCT images showed complete iodized oil retention patterns (type I) in 29/40 (73%) tumours, at which point embolization was terminated; incomplete iodized oil retention requiring further iodized oil embolization occurred in 11/40 (28%) tumours and, of these, complete iodized oil retention patterns were achieved in eight tumours. Conventional CT scanning employed 1 week later showed the same iodized oil retention patterns as demonstrated in the latest CCT images (37/40 [93%] tumours). In 24 additional HCC patients who underwent TACE but not CCT (control group), conventional CT scans obtained 1 week after TACE showed complete iodized oil retention in 32/42 (76%) tumours. The rate of complete iodized oil retention pattern was significantly higher in patients undergoing CCT. It is concluded that the distribution of iodized oil within HCC lesions can be demonstrated on CCT images during TACE, helping to achieve complete iodized oil filling of tumours and, thereby, improving therapeutic effects.


Asunto(s)
Angiografía/instrumentación , Carcinoma Hepatocelular/tratamiento farmacológico , Cateterismo/métodos , Quimioembolización Terapéutica/métodos , Aceite Yodado/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Tomografía Computarizada por Rayos X/instrumentación , Adulto , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Femenino , Fluoroscopía , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad
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