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Regulating off-centering distortion maximizes photoluminescence in halide perovskites

national Science Review 2021年第9期8卷 60-67页

作者： Xujie Lu Constantinos Stoumpos Qingyang Hu Xuedan Ma Dongzhou Zhang Songhao Guo justin Hoffman Kejun Bu Xiaofeng Guo Yingqi Wang Cheng Ji Haijie Chen Hongwu Xu Quanxi Jia Wenge Yang Mercouri G.Kanatzidis Ho-Kwang Mao Center for High Pressure Science and Technology Advanced Research Department of Chemistry Northwestern University Department of Materials Science and Technology Voutes Campus University of Crete Center for nanoscale Materials Argonne National Laboratory Partnership for Extreme Crystallography University of Hawaii at Manoa Department of Chemistry and Alexandra navrotsky Institute for Experimental Thermodynamics Washington State University Earth and Environmental Sciences Division Los Alamos National LaboratoryLos Alamos Department of Materials Design and Innovation University at Buffalo The State University of New York

Metal halide perovskites possess unique atomic and electronic configurations that endow them with high defect tolerance and enable high-performance photovoltaics and optoelectronics. Perovskite light-emitting diodes have achieved an external quantum efficiency of over 20%. Despite tremendous progress,fundamental questions remain, such as how structural distortion affects the optical properties. Addressing their relationships is considerably challenging due to the scarcity of effective diagnostic tools during structural and property tuning as well as the limited tunability achievable by conventional methods. Here,using pressure and chemical methods to regulate the metal off-centering distortion, we demonstrate the giant tunability of photoluminescence (PL) in both the intensity (>20 times) and wavelength(>180 nm/GPa) in the highly distorted halide perovskites [CH3nH3GeI3, HC(nH2)2GeI3, and Cs Ge I3].Using advanced in situ high-pressure probes and first-principles calculations, we quantitatively reveal a universal relationship whereby regulating the level of off-centering distortion towards 0.2 leads to the best PL performance in the halide perovskites. By applying this principle, intense PL can still be induced by substituting CH3nH~3+with Cs~+to control the distortion in (CH3nH3)1-xCsxGeI3, where the chemical substitution plays a similar role as external pressure. The compression of a fully substituted sample of CsGe I3further tunes the distortion to the optimal value at 0.7 GPa, which maximizes the emission with a10-fold enhancement. This work not only demonstrates a quantitative relationship between structural distortion and PL property of the halide perovskites but also illustrates the use of knowledge gained from high-pressure research to achieve the desired properties by ambient methods.

关键词： halide perovskites high pressure off-centering distortion optical properties lone-pair electrons quantitative relationship

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Genome-wide SnP Genotyping Resolves Signatures of Selection and Tetrasomic Recombination in Peanut

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Molecular Plant 2017年第2期10卷 309-322页

作者： Josh Clevenger Ye Chu Carolina Chavarro Gaurav Agarwal David J. Bertioli Soraya C.M. LeaI-Bertioli Manish K. Pandey justin Vaughn Brian Abernathy noelle A. Barkley Ran Hovav Mark Burow Spurthi n. nayak Annapurna Chitikineni Thomas G. Isleib C. Corley Holbrook Scott A. Jackson Rajeev K. Varshney Peggy Ozias-Akins Department of Horticulture and Institute of Plant Breeding Genetics & Genomics The University of Georgia 2356 Rainwater Road Tifton GA 31793 USA Center for Applied Genetic Technologies and Institute of Plant Breeding Genetics & Genomics The University of Georgia Athens GA 30602 USA International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) Hyderabad 502324 India University of Brasilia Institute of Biological Sciences Campus Darcy Ribeiro 70910-900 Brasilia DF Brazil Embrapa Genetic Resources and Biotechnology 70770-917 Brasflia DF Brazil eUSDA-ARS PGRCU Griffin GA 30223 USA Agricultural Research Organization Plant Sciences Institute 7528809 Rishon LeZion Israel Department of Plant and Soil Science Texas Tech University Lubbock TX 79409-2122 USA Department of Crop and Soil Sciences North Carolina State University Box 7629 Raleigh NC 28695-7629 USA USDA-ARS Tifton GA 31793. USA

Peanut （Arachis hypogaea; 2n = 4x = 40） is a nutritious food and a good source of vitamins, minerals, and healthy fats. Expansion of genetic and genomic resources for genetic enhancement of cultivated peanut has gained momentum from the sequenced genomes of the diploid ancestors of cultivated peanut. To facil- itate high-throughput genotyping of Arachis species, 20 genotypes were re-sequenced and genome-wide single nucleotide poiymorphisms （SnPs） were selected to develop a large-scale SnP genotyping array. For flexibility in genotyping applications, SnPs polymorphic between tetraploid and diploid species were included for use in cultivated and interspecific populations. A set of 384 accessions was used to test the array resulting in 54 564 markers that produced high-quality polymorphic clusters between diploid species, 47 116 polymorphic markers between cultivated and interspecific hybrids, and 15 897 polymorphic markers within A. hypogaea germplasm. An additional 1193 markers were identified that illuminated genomic re- gions exhibiting tetrasomic recombination. Furthermore, a set of elite cultivars that make up the pedigree of US runner germplasm were genotyped and used to identify genomic regions that have undergone pos- itive selection. These observations provide key insights on the inclusion of new genetic diversity in culti- vated peanut and will inform the development of high-resolution mapping populations. Due to its efficiency, scope, and flexibility, the newly developed SnP array will be very useful for further genetic and breeding applications in Arachis.

关键词： single nucleotide polymorphism groundnut Arachis hypogaea

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Correlates of subjectively and objectively measured physical activity in young adolescents

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Journal of Sport and Health Science 2015年第3期4卷 222-227页

作者： Kelly Kavanaugh justin B. Moore Leisha Johnson Hibbett Andrew T. Kaczynski Office of Practice and Community Engagement University of South Carolina Columbia SC 29208 USA Department of Health Promotion Education and Behavior University of South Carolina Columbia SC 29208 USA Coastal Community Action Newport NC 28570 USA

Background： Many studies examining individual-level correlates in youth utilize self-report rather than objective measures of physical activity （PA）. This utilization of self-report may result in associations that are not present when examining objectively measured PA. The present study investigates the relationship between hypothesized correlates of PA with objectively and subjectively measured PA. Methods： Participating children （n 232, 101 males, mean age - 12.3 years） provided a minimum of four monitored days of PA （via accelerometer） and completed a survey assessing moderate-to-vigorous physical activity （MVPA）, sport competence, appearance, enjoyment, and self-efficacy. Height and weight were measured and body mass index （BMI） was calculated. Results： Hierarchical regression models controlling for sex, race, and BMI Z-score showed that only sex and BMI Z-score were significant correlates of objective MVPA while only sex was a significant correlate of objective total PA. However, in a separate model examining the relationship with subjective MVPA, enjoyment of PA and self-efficacy for PA were the only significant correlates of self-reported PA. Conclusion： Measuring MVPA via self-report versus accelerometry produces considerably different results in a sample of young adolescents. Future studies should use caution when selecting outcome measures if the intent is to identify modifiable correlates of MVPA in youth.

关键词： Accelerometry Enjoyment Self-efficacy Youth

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Anionic nanochanneled Silver-Deficient Oxalatochromate(III) Complex with Hydroxonium as Counter Ion: Synthesis, Characterization and Crystal Structure

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Open Journal of Inorganic Chemistry 2017年第3期7卷 75-87页

作者： Clémence T. Eboga Gouet Bebga Yves A. Mbiangué Emmanuel n. nfor Patrick L. Djonwouo Michel M. Bélombé justin nenwa Inorganic Chemistry Department University of Yaounde Yaounde Cameroon Chemistry Department Higher Teacher Training College University of Yaounde 1 Yaounde Cameroon Chemistry Department Higher Teacher Training College University of Maroua Maroua Cameroon Department of Chemistry University of Buea Buea Cameroon

Reaction of Ba0.50[Ag2Cr(C2O4)3]·5H2O with Ag2SO4 in an aqueous solution of sulfuric acid (pH ≈ 3) yielded the silver(I)/chromium(III) oxalate salt H0.50[Ag2.50Cr(C2O4)3]·5H2O (1). Compound 1 can be best described as an anionic silver-deficient oxalatochromate(III) complex [Ag2.50Cr(C2O4)3]0.5- with nanochannels containing hydrogen-bonded water molecules and protons. Thermal analyses show significant weight losses corresponding to the elimination of water molecules of crystallization followed by the decomposition of the network.

关键词： Silver-Deficient Oxalatochromate(III) Water-Filled nanochannels Protons Thermal Analysis Crystal Structure

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Epidemiology and Histology Aspects of Breast Cancers of Women in Ivory Coast

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Journal of Cancer Therapy 2012年第5期3卷 782-786页

作者： justin n’Dah Kouame Emile Troh Emmanuel Koffi Kouakou Brahima Doukouré Arthur Didier Kouame Alain Didier Abouna Benjamin Ahoua Effi Mohenou I Diomandé Department of Gynecology of the University Teaching of Cocody Abidjan Ivory Coast Department of Pathology of the University Teaching of Bouake Abidjan Ivory Coast Department of Pathology of the University Teaching of Cocody Abidjan Ivory Coast Department of Pathology of the University Teaching of Treichville Abidjan Ivory Coast

Breast cancer is a major public health problem both in developed countries, where it represents the first female cancer, and in developing countries, where its incidence is increasing. Purpose: The authors report the results of a study whose objective was to describe the epidemiological and pathological features of women’s breast cancers in Ivory Coast. Material and Methods: This is a retrospective descriptive study on breast cancer histologically confirmed and made from the records of pathology laboratories of the University Hospital in Abidjan. The study period was 24 years (1984-2007). The parameters studied were: frequency, age, risk factors, the macroscopic and histological aspects. Results: Women’s breast cancer was the second cancer among women (13.69%) after cervical cancer and represented 6.51% of cancers. The average age was 45.21 years ranging from 10 years to 85 years. Subjects from 35 to 44 years were the most affected (30.7%) and 8% of patients were under 30 years (n=61). Multiparity (53.55%) and lower socioeconomic level (79.63%) were associated. At the macroscopic level nodular aspects represented 47.62% of cases (n=301). Carcinomas were 92% (n=710) of histological types with 94.36% (n=692) of invasive carcinomas. Sarcomas (5.7%), lymphoma (2.1%) and Paget’s disease (0.3%) were also observed. With regard to prognostic, the grading of Scarff-Bloom and Richardson showed 26.75% (n=156) grade I, 60.64% (n=354) grade II and 12.52% (n=73%) grade III. Conclusion: In consideration of prognosis of advanced forms, an effort should be made for diagnosis and early treatment of women’s breast cancer in Ivory Coast.

关键词： Cancer Breast Epidemiology Pathology Ivory Coast

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Kinetics of Sorption of Pendimethalin on Soil Samples Obtained from the Banks of Rivers Katsina-Ala and Benue, Central nigeria

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Journal of Geoscience and Environment Protection 2016年第1期4卷 37-42页

作者： justin Kpagh Rufus Sha’Ato Raymond A. Wuana Terrumun A. Tor-Anyiin Department of Chemistry University of Agriculture Makurdi Nigeria

Kinetics of the sorption of the herbicide, pendimethalin (3,4-Dimethyl-2,6-dinitro-n-pentan-3-yl-aniline) on four soil samples obtained from the banks of Rivers Benue and Katsina-Ala, in Central nigeria was studied by contacting 5.0 g soil samples with 100 mL 7 × 10-6 M herbicide solution. The sorption was monitored by following the herbicide concentration in the aqueous phase spectrophotometrically at one hour intervals for 5 hours (at 25°C, 35°C, 45°C, 55°C and 65°C, respectively). Pseudo-first order kinetics treatment of the data showed that sorption rates as well as the accompanying activation energies were low, indicating that physical adsorption is the operative mechanism for its retention in the soils and that the herbicide tended to reside more in the aqueous phase, which raised its potential to contaminate natural water systems, when applied on the field.

关键词： Kinetics Sorption Pendimethalin Soil nigeria

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Epidemiological and Histological Aspects of Women Genital Cancers in Cote d’Ivoire

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Open Journal of Obstetrics and Gynecology 2014年第9期4卷 516-523页

作者： Kouamé justin n’Dah Brahima Doukoure Emile Troh n’Guessan Alphonse Aman Kouakou Emmanuel Koffi Arthur Didier Kouamé Ahoua Benjamin Effi Ahoua Francois de Salès D’Horpock Mohénou Isidore Jean-Marie Diomande Laboratory of Pathology University Hospital of CocodyAbidjanCôte d’Ivoire Department of Pathology Saint-Louis HospitalParisFrance Laboratory of Pathology University Hospital of BouakeBouakeCôte d’Ivoire Laboratory of Pathology University Hospital of TreichvilleAbidjanCôte d’Ivoire Department of Obstetrical Gynecology University Hospital of CocodyAbidjanCôte d’Ivoire

Genital cancers in women play an important role in cancer pathology in the developing countries. Objectives: This study aimed at clarifying the epidemiological and histopathological aspects of woman genital cancers in C?te d’Ivoire. Materials and Methods: This was a retrospective and descriptive study conducted in the anatomical pathology laboratories of the university hospitals in Abidjan. The study was carried out over a period of twenty-four years (1984-2007). The variables studied were: frequency, age, histological type and prognosis. Results: Genital cancers in women accounted for 41.28% (n = 2491) of cancer in women and 21% of cancers. The average age of patients was 46.65 years (range 2 - 88 years). The cervix (82.85%) was the main location followed by the ovary (8.6%). Histologically, carcinomas (92.93%) were the most common types of sarcomas. Cervical cancers were diagnosed at an average age of 47.36 years (range 2 to 88 years). Carcinomas were the predominant histological type (92.88%) with 57.4% (n = 450) diagnosed at pT2n0M0 stage. The average age of patients bearing ovarian cancer was 39.13 years (range 8 to 82 years).Common malignant epithelial tumours were the most common histological type (57.48%) (n = 123) followed by non-Hodgkin lymphoma (14.95%). Conclusion: Genital cancers in women are common and poorly prognosed in Cote d’Ivoire. The adoption of a policy of routine screening is needed to improve the prognosis of these tumours.

关键词： Cancer Genital Women Epidemiology-Histology-C?te d’Ivoire

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Evolution of a Disseminated Peritoneal Leiomyomatosis: About a Case

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Open Journal of Obstetrics and Gynecology 2017年第7期7卷 742-747页

作者： Kouamé Arthur Didier Adjoby Cassou Roland Koffi Achille Konan K. Joachin Alla Christian Hervé Kouamé n’Da justin I. S. Baldé Kouakou Firmin Obstetrics and Gynecology Department University Hospital of Cocody Abidjan C&ocirc te D’Ivoire Laboratory of Pathology University Hospital of Cocody Abidjan C&ocirc te d’Ivoire Obstetrics and Gynecology Department of Ignace Deen Hospital of Conakry Conakry Guinea

Disseminated peritoneal leiomyomatosis (DPL) is a benign tumor of smooth muscle tissue. It is rare and is characterized by the development of multiple peritoneal nodules simulating peritoneal carcinosis. Less than 200 cases have been reported in the literature so far. We are reporting a case of DPL detected during a Caesarean section 6 years ago in a 41-year-old female patient, G5P2. The patient underwent an elective iterative caesarean section at 38 weeks of amenorrhea for a fetus in breech presentation. During laparotomy, there was a marked regression of the peritoneal nodules varying in size from 0.1 to 0.5 cm. Histological examination showed a proliferation of smooth muscle fibers without mitosis, atypia or necrosis. DPL is a benign, confusing condition that simulates peritoneal carcinomatosis, which must be recognized as such in order to avoid a dilapidated and unnecessary surgical procedure.

关键词： Disseminated Peritoneal Leiomyomatosis Uterine Leiomyoma Caesarean Section

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The Stigma of Epilepsy among Outpatients in a Tertiary Hospital in South-East nigeria

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Open Journal of Psychiatry 2017年第4期7卷 344-364页

作者： justin U. Achor Birinus A. Ezeala-Adikaibe Okwudili n. Obayi Chinwe F. S. Ezeruigbo Oluchi S. Ekenze Obinna D. Onodugo Federal neuropsychiatric Hospital Enugu New Haven Nigeria Department of Medicine University of Nigeria Teaching Hospital Ituku/Ozalla Nigeria Department of Psychological Medicine Ebonyi State University Abakaliki Nigeria Department of nursing Sciences Faculty of Health Science Ebonyi State University Abakaliki Nigeria

Background: The stigma of epilepsy is pervasive in developing country contexts and negatively affects the psychological and social wellbeing of its sufferers. The experience of stigma varies across settings and probably relate to disease severity and social characteristics. This study sought to describe the extent and correlates of perceived and enacted stigma among outpatients with epilepsy. Methods: The participants were consecutively presenting epilepsy outpatients in a tertiary facility that attended clinic regularly and had no overt medical or psychiatric co-morbidities. The patients were interviewed with a semi-structured questionnaire. Results: There were 93 participants with a mean age of 30.2 ± 10.3 years and 57.0% were males. The experience of stigma was reported by 46.2% and 67.7% of the participants for perceived and enacted stigma, respectively. Over one-third of the patients had suffered burns or a similar injury in the past. The correlates of perceived stigma were rural residence, lower levels of education, and longer duration of illness. Gender, age and frequency of seizures were not statistically significant determinants. The correlates of enacted stigma were being single, older age, rural residence, and longer duration of epilepsy. A past history of burns and disclosure of epilepsy to individuals outside the family added to the likelihood of experiencing stigma. Conclusion: The burden of epilepsy related social stigma is high in nigeria. Cultural stereotypes and misconception add to this. There is need for appropriate culture-congruent educational interventions to provide the right information about epilepsy and debunk the misconceptions and myths associated with the condition. This will need to be coupled with astute clinical management of cases and active case finding. Both qualitative and longitudinal quantitative studies would be required to deepen our understanding of the lived reality of grappling with stigma in our setting.

关键词： Epilepsy Stigma Perceived/Enacted nigeria

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Single hepatocellular carcinoma ≤ 3 cm in left lateral segment:Liver resection or radiofrequency ablation?

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World Journal of Gastroenterology 2014年第14期20卷 4059-4065页

作者： Jong Man Kim Tae Wook Kang Choon Hyuck David Kwon Jae-Won Joh justin Sangwook Ko Jae Berm Park Hyunchul Rhim Joon Hyeok Lee Sung Joo Kim Seung Woon Paik Department of Surgery Samsung Medical CenterSungkyunkwan University School of Medicine Department of Radiology and Center for Imaging Science Samsung Medical CenterSungkyunkwan University School of Medicine Department of Anesthesiology and Pain Medicine Samsung Medical CenterSungkyunkwan University School of Medicine Division of Gastroenterology Department of MedicineSamsung Medical CenterSungkyunkwan University School of Medicine

AIM: To evaluate the long-term results of radiofrequency ablation (RFA) compared to left lateral sectionectomy (LLS) in patients with Child-Pugh class A disease for the treatment of single and small hepatocellular car... 详细信息

关键词： Small hepatocellular carcinoma Left lateral segment Radiofrequency ablation Liver resection Tumor recurrence Survival

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