bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on magnetic transition behavior for (Pr1－yNdy)2/3Sr1/3MnO3 system under superposed fields
Authors: Kang Bao-Juan  , Cao Shi-Xun  , Wang Xin-Yan  , Li Ling-Wei  , Li Wen-Feng  , Liu Fen  , Cao Gui-Xin  , Yu Li-Ming  , Jing Chao  , Zhang Jin-Cang  ,   上海大学物理系，上海  200436
Published: December 2020

The magnetic transition behaviors of (Pr1-yNdy)2/3Sr 1/3MnO3(y=2/8,4/8,6/8) polycrystalline samples under superposed ma gnetic fields (i.e., the superposed ac and dc magnetic field) were systematicall y studied at temperatures ranging from 42 to 300K. The results showed that the magnetization increases with the increase of magnetic field, and the real part of the ac susceptibility decreases as the superposed dc magnetic field increases . Under the superposed magnetic field, a characteristic sharp peak of the real p art of the susceptibility appears near the magnetic transition temperature (Curi e temperature). For the (Pr1-yNdy)2/3Sr1/3MnO 3 system, as the Nd content increases, the peak temperature of the relative variation of the real part of susceptibility (Eχ′=Δχ′/χ′ dc) decreases, in consistent with that of the magnetoresistivity of this sys tem. The magnetic transition behaviors under superposed magnetic fields for the manganite systems are discussed.
The light pulses and the spectra of conical bubbles sonoluminescence
Authors: He Shou-Jie  , Chen Qi-Dai  , Li Xue-Chen  , Ai Xi-Cheng  , Zhang Jian-Ping  , Wang Long  ,   (1)河北大学物理科学技术学院, 保定  071002; (2)河北大学物理科学技术学院, 保定  071002;中国科学院物理研究所,       北京  100080; (3)中国科学院化学研究所,       北京  100080; (4)中国科学院物理研究所,       北京  100080
Published: December 2020

Based on the original design of T.G.Leighton's conical bubble U_tube，an improve d apparatus is set up. The light pulses and spectra of air bubbles in water are detected. Results show that the width of a light pulse ranges from a few of hun dred picoseconds to a few nanoseconds. The vibrational spectra of water molecule s in the near_infrared have been obtained，and its intensity increases toward th e infrared. The spectra of conical bubble in NaCl solution is also detected.
Fabrication and structure studies of Co：BaTiO3 nano composite thin films
Authors: Zhang Chao  , Wu Wei-Dong  , Chen Zheng-Hao  , Zhou Yue-Liang  , Cheng Xin-Lu  , Yang Xiang-Dong  , He Ying-Jie  , Sun Wei-Guo  , Tang Yong-Jian  ,   (1)四川大学原子与分子物理研究所，成都  610064; (2)中国工程物理研究院激光聚变研究中心，绵阳  621900; (3)中国工程物理研究院激光聚变研究中心，绵阳  621900;四川大学原子与分子物理研究所，成都  610064; (4)中国科学院物理研究所，北京  100080
Published: December 2020

Co:BaTiO3 nano_composite thin films on single_crystal magnesia(100) were successfully fabricated by pulsed laser deposition. The morphology and microstructure of the thin films were investigated via atomic force microscope, x_ray diffractometer and Raman spectroscopy. The results show that the thin films consisted o f a highly c_axis oriented tetragonal phase. The surfaces of the thin films were uniform, compact and of atomic smoothness (RMS=015nm). The co particles, of monodisperse distribution, were found to be well dispersed in the matrix Co: BaTiO3. With increasing Co grain size, the intensities of Raman peaks were wea kened and their width broadened.
Mary Kaasiku ja Gustav Kallasto rahvaluulekogu ning kirjavahetus
Authors:   Estonian Literary Museum, Estonia, Goršič Ave
Published: December 2020

The broader source material for this article is the Soviet-era correspondence of the Folklore Department (FD) of the Fr. R. Kreutzwald State Literary Museum, today the Estonian Folklore Archive of the Estonian Literary Museum. This collection consists of letters and postcards of nearly 400 people, as well as transcripts of the FD staff letters to their contributors. The total volume amounts to roughly 4,000 pages and mainly covers the period from the 1950s to the first half of the 1990s. The article also discusses the contributions of Virumaa correspondents Mary Kaasik and Gustav Kallasto to the department, more specifically the folk medicine material collected by them, and focuses on Kaasik and Kallasto’s correspondence with the department, with the main emphasis on the personal health issues in their letters. Mary Kaasik and Gustav Kallasto were among those who collected folk medicine material according to the 1959 survey plan, assembled in co-operation with the folklorists and medical doctors. Assessing the total amount of material collected by Kaasik and Kallasto (over 3300 pages), the folk medicine material is not very large (over 200 pages), but it is one of the topics in which Mary Kaasik and Gustav Kallasto wrote down personal knowledge or experiences. The correspondence shows that their health problems were constantly reflected both in their letters and as short comments among traditional folk medicine material. Mary Kaasik was more inclined towards sharing her problems and personal knowledge and was the one who wrote to the department on behalf of both collectors. In general, it is concluded that personal health has been an important topic in the letters of the contributors to the folklore department. Health problems were a major obstacle to commuting and attending seminars; so messages about the health of oneself, one’s relatives or other collectors or informants are part of the content of the letters. On the other hand, health also comes to the fore in the letters of folklorists, who in turn informed their contributors about their own or their colleagues’ health, if deemed necessary. At the same time, writing about health issues creates an interesting dialogue thread between the correspondents and the folklorists, with mutual encouragement and pleas to take care of one’s health. Thus, a rather personal life goes hand in hand with the practical requirements stated in letters on collecting and archiving. Thus, much data on health can be found in the department’s correspondence. Health-related messages are personal and trusting, the majority of correspondents did not have internal obstacles to share their health worries and to enquire for folklorists’ health. It meant sharing problems and probably provided some well-deserved mental relief. On the other hand, these kinds of letters also show the correspondents’ sense of mission – even when they were off sick, they were eager to get back to the field again.
Marketing Capabilities of Early Internationalising Firms
Authors: Mitić Sanja , Rakita Branko
Published: December 2020

Research Question: The topic of this study is marketing capabilities of early internationalising firms from Serbia. Motivation: As marketing perspective was found to be important for understanding the early internationalisation phenomenon, the aim of this study is to shed light on the marketing capabilities of early internationalising firms from Serbia. This topic was widely examined in the developed countries, but there is an evident lack of research in developing countries, especially in the Western Balkans. Understanding the specifics of early internationalising firms can provide valuable policy and managerial implications for stimulating export activities of small and medium-sized firms. Idea: The idea of the paper is to identify the main marketing capabilities of early internationalising firms from Serbia.  Data: Primary data were collected through semi-structured interviews with the founders or managers of four firms from Serbia, over the period from August 2018 to January 2019. Tools: As this topic is not widely investigated in Serbia and other Western Balkan countries, a case study method was found to be appropriate. Primary data were completed with secondary data sources. Findings: The results show that in terms of marketing capabilities, early internationalising firms from Serbia express similar features as the ones already recognized in the literature. They develop differentiated, high quality and innovative products, specialized for a particular market niche or segment. Contribution: This study provides the results of the first primary research on the marketing capabilities of early internationalising firms from Serbia and offers valuable implications for managers, for developing an effective international marketing strategy, as well as policy implications for export support programmes and small and medium-sized firms’ policy.
Service Quality of the Higher Vocational Education
Authors: Jovičić Vuković Ana , Damnjanović Jelena , Papić-Blagojević Nataša
Published: December 2020

Research Question: The paper will investigate the service quality of the higher education provided by the higher schools of vocational studies using SERVQUAL methodology. Motivation:  The paper will show the characteristics of higher education of vocational studies, and it will point out the significance of creating and maintaining a quality management system in higher education institutions. The new reform of higher education in Serbia and establishment of academies of vocational studies are the main reasons why the question of service quality becomes one of the most important issues for higher education institutions and basis for competitive advantage, better image and reputation. Also, a growing competition on the higher education market and a smaller number of prospective students are also problems which higher vocational schools are faced with. Idea: The goal of this research is to find the differences between expected and perceived service quality. Furthermore, the paper will show if there are differences between perceived service quality among the students of different study years, as well as differences between the students with State scholarship and the self-funded students. Data: The research included 244 students of the first, second, and third years of bachelor studies from higher schools of vocational studies in Novi Sad, significant and the second-largest educational centre in the Republic of Serbia. Tools: Statistical methods used in this paper are frequency analysis, descriptive statistics, while the hypotheses are tested using the paired sample t-test, the independent t-test, and the one-factor variance analysis – ANOVA. Findings: The results of the research show that service quality of higher vocational education does not meet students' expectations (sig.<0,001)  and that the gap is negative for all dimensions of service quality (Tangibles (-.32), Reliability (-.52), Responsiveness (-.49), Assurance (-.33), and Empathy(-.26)). It is also shown by this research that there are no differences in higher education service quality based on the status of students (sig.>0.05) and the year of studying (sig.>0.05). Contribution: The results can be used as basis for introducing further measures to improve the quality of service provided by higher vocational institutions.
Drivers Affecting Online Banking Usage of Private Commercial Banks in Sri Lanka
Authors: Hapuarachchi Chathura , Samarakoon Ajantha
Published: December 2020

Online banking is the compulsory condition to develop e-business within the world. The key objective of the study is to examine drivers affecting online banking facility usage of the private commercial banks in Sri Lanka. The researcher has selected five factors namely perceived risk, customers’ concern for privacy, customers’ value for online personalization, e-trust, and e-loyalty after considering previous studies and expert idea in the field. Five hundred questionnaires were distributed among the customers who attached to the seven main private commercial banks and living selected three prominent provinces of three prominent cities namely Kandy, Colombo & Galle in Sri Lanka. Although only two hundred fifteen questionnaires received from the online customers. One hundred ninety-six complete questionnaires used to the final data analysis. Descriptive statistics, correlation analysis and Multiple regression analysis utilized to analysis the data.

Data analysis result of the study shows that perceived risk, customers’ concern for privacy and entrust show the significant positive effect on online bank usage in Sri Lanka. E-loyalty and customers’ value for privacy also positively influence on online bank usage, however these two factors didn’t show the significant influence on online bank usage. Sri Lankan commercial banks should promote online bank usage by considering risk, customers’ concern for privacy and entrust. Moreover, online program designers should concern innovations and significant factors when they develop online bank platforms. Further, the researchers should conduct further research base on different cultures to identify the issues and significant factors that may influence on online banking usage.
Characteristic Variation of Ground Heat Flux and Net Radiation at Tropical Station in Ile-Ife, Osun State, Nigeria
Authors: Usman A. , Ibrahim B. B. , Sunmonu L. A.
Published: December 2020

Characteristic variation of ground heat flux and net radiation enhances the understanding of the significance of indicated trends of variability to everyday life and factors that might be responsible for such variations. This research work critically analyses some specific days with field data over grass-covered surface at Ile-Ife, Nigeria between ground heat flux and net radiation. For the field observations, an instrumented meteorological mast was set up at an experimental site (7°33’N, 4°35’E) located at Obafemi Awolowo University campus, Ile-Ife, Nigeria for a period of two weeks (31st May-14th June, 2013). The soil heat flux, net radiation and soil temperature from the soil heat flux plate; an all-wave net radiometer, and soil thermometer were recorded every 10 seconds and averaged over 2 minutes interval. The sampled data was stored in the data logger (Campbell Scientific, Model CR10X) storage module. After the removal of spurious measurement values (Quality Assurance and Quality Control), the data stored was further reduced to 30 minutes averages using the Microcal Origin (version 7.0) data analysis software. The results showed that the measured ground heat flux, HGM during the daytime increases until 1400 hrs with maximum value of about 136.86 Wm-2 and minimum value of about -72.87 Wm-2 at 0830 hrs (DOY 156). The measured net radiation, Rn value of 649.65 Wm-2 observed at 1400 hrs (DOY 156), represented the maximum value for the entire period of the study. -10.75 Wm-2 value observed at1800 hrs (DOY 154), represented the minimum value for the entire period of the study due to the cloudy condition of the sky which reduces the amount of incoming solar radiation reaching the earth surface.
Technical Efficiency Analysis of Pineapple Production at Madhupur Upazila of Tangail District, Bangladesh
Authors: Akter Khadija , Majumder Shankar , Islam Mohammad Amirul , Sarker Bishwajit
Published: December 2020

The main objective of this study is to analyse the technical efficiency and its determinants of pineapple production at Madhupur upazila of Tangail district in Bangladesh. Cross-section data from a sample of 100 pineapple producers during the 2016-17 cropping season were collected by applying multistage random sampling technique. Farm specific technical efficiency scores were estimated using the Cobb-Douglas stochastic frontier production function approach. Empirical findings show that the estimated technical efficiencies of the sampled farmers’ range from 61.61% to 99.95% with the mean technical efficiency of 91.14%. The result suggests that, on an average, farmers in the study area can potentially increase their productivity by 8.86% through more efficient use of inputs. The estimated stochastic production frontier model indicates that input variables such as area, tillage cost, seedling cost and human labour cost were statistically significant variables to increase the quantity of pineapple production. Technical inefficiency effect model identifies that age of farmers had significant positive, but years of schooling and extension contact had significant negative effect on farmers’ inefficiency. The study therefore recommends that government should focus on the ways of attracting and encouraging the youths as they are more efficient and are likely to be able to properly allocate resources and are willing to adopt new technical innovations. Besides, policies and strategies should be directed towards increasing farmers’ formal as well as informal education through the implementation of effective training programmes by the well-trained extension workers.
Evaluation of Genetic Divergence among Barley Genotypes Based on Agro-Morphological Characters
Authors: Jalata Zerihun , Garoma Belay , Nandeshwar B. C.
Published: December 2020

The knowledge of nature and the magnitude of divergence existing in the breeding materials are useful to identify suitable parents or populations to combine favorable genes. Thus, 28 barley genotypes were evaluated at Gitilo site in RCB design with three replications during the 2018/19 season. The aim of the study was to investigate the magnitude of genetic divergence among the existing breeding materials. The result revealed that the barley genotypes were grouped into four clusters. The inter-cluster distance was greater between clusters I and II, followed by cluster II and III and then between clusters II and IV, I and IV, III and IV, between I and III so that crossing among parents from distant clusters result in wide array populations with desirable alleles. Besides this, cluster mean analysis showed clusters IV and III contained desirable characters for high yield potential including net blotch and scald resistance indicating their suitability for direct variety development. The variation studied through principal component analysis revealed four principal components (PC1:32.7%, PC2:22.4%, PC3:16.7% and PC4:11.6%) accounting for about 83.4% of the total variation. Furthermore, the biplot graph identified barley genotypes or populations 21, 20, 24 and 12 as desirable parents mainly for grain yield, biomass yield per plant and thousand kernel weights.
Design of Solar Blind Photodetectors for Communication with Green Signal (λ= 0.532µm) in Space. Part II
Authors: Shtein Samson Mil’ , Asthana Dhawal
Published: December 2020

The areas of Free Space Optical (FSO) communication and high-speed Visible Light Communication (VLC) offer potential for very high-speed data transmission. Favorable attributes including high frequency and wider bandwidths that can enable transmission speeds of the order 100Gb/s, associated with the visible region of the electromagnetic spectrum make it preferable for allowing communication among satellites and ground stations, under-water communication, etc. However, limitations associated with spectral absorption characteristics of the propagating media have stymied further development of such technologies.

Aims: Commercial lasers operating in red, green and blue lights combined with three photodetectors, each sensitive to selected wavelengths (colors) present basics of long-distance optical communication system. The current study (Part II) depicts the design and operation of a solar-blind photodetector capable to work explicitly with green wavelength of 532nm.

Study Design and Results: The structure of the solar-blind photodetector consists of two sections made of InxGa1-xN (Indium Gallium Nitride) heterostructure, (where x denotes the mole fraction)-a filter and a double barrier tunneling diode. The topmost approximately 1µm thick section acts as a filter and as a p-i-n solar cell providing the required voltage bias to the photodiode. The filter with Eg (Energy Band Gap)=2.33eV absorbs all photons having wavelengths shorter than 532nm. The double barrier tunneling photodiode which comprises the lower section operates with Eg=2.28eV. It consists of an n-type lightly doped quantum well having a width of 2.5nm housed between two lightly doped barriers of 10nm thickness. The 0.12µm topmost and bottom regions of the photodiode are doped with p and n (2×105cm-3) type impurities, respectively. The illuminated cross-section area of the device is finalized at 1mm2.
Digital Tourism Marketing 4.0 Collaborative Strategy for Banggai Brothers Area, Central Sulawesi, Indonesia
Authors: Akbar Rully Anggi , Priyambodo Tri Kuntoro , Kusworo Hendrie Adji , Fandeli Chafid
Published: December 2020

Aims: This study aims to analyze the obstacles in digital tourism marketing in The Banggai brothers area (Banggai Luwuk, Banggai Islands, Banggai Laut), Central Sulawesi, to analyze the digital marketing strategies that have been applied and to formulate an effective collaborative digital tourism marketing strategy that can be used, and applied to the Banggai brothers in the future.

Study Design: This research study design is a qualitative study

Place and Duration of Study: This research was conducted in the Banggai brothers (Banggai Luwuk, Banggai Islands, Banggai Laut) Central Sulawesi, Indonesia, in February - June 2020. Methodology: This qualitative research method uses a case study. Collecting data through interviews and direct observation with regional tourism offices, destination management, local communities, and visitors to tourism objects in the Banggai brothers. Data analysis using Grounded Analysis (Reduction, Display, and Drawing Conclusion / Verification).

Results: The result of this research is The dominant problem is the limited human resources in tourism.

Conclusion: The marketing strategy plan aimed at the Banggai Brothers area is Digital collaboration tourism, namely; Planning phase using a collaborative market system. The implication of this research can help create a collaborative tourism marketing strategy 4.0 based on internet use, especially social media, for the Banggai area and destinations throughout Indonesia.
Cleaning the dose falloff in lung SBRT plan
Authors: Desai Dharmin , Narayanasamy Ganesh , Bimali Milan , Cordrey Ivan , Elasmar Hisham , Srinivasan Senthamizhchelvan , Johnson Ellis Lee
Published: December 2020

Purpose

To investigate a planning technique that can possibly reduce low‐to‐intermediate dose spillage (measured by R50%, D2cm values) in lung SBRT plans.

Materials and Methods

Dose falloff outside the target was studied retrospectively in 102 SBRT VMAT plans of lung tumor. Plans having R50% and/or D2cm higher than recommended tolerances in RTOG protocols 0813 and 0915 were replanned with new optimization constraints using novel shell structures and novel constraints. Violations in the RTOG R50% value can be rectified with a dose constraint to a novel shell structure (“OptiForR50”). The construction of structure OptiForR50% and the novel optimization criteria translate the RTOG goals for R50% into direct inputs for the optimizer. Violations in the D2cm can be rectified using constraints on a 0.5 cm thick shell structure with inner surface 2cm from the PTV surface. Wilcoxon signed‐rank test was used to compare differences in dose conformity, volume of hot spots, R50%, D2cm of the target in addition to the OAR doses. A two‐sided P‐value of 0.05 was used to assess statistical significance.

Results

Among 102 lung SBRT plans with PTV sizes ranging from 5 to 179 cc, 32 plans with violations in R50% or D2cm were reoptimized. The mean reduction in R50% (4.68 vs 3.89) and D2cm (56.49 vs 52.51) was statistically significant both having P < 0.01. Target conformity index, volume of 105% isodose contour outside PTV, normal lung V20, and mean dose to heart and aorta were significantly lowered with P < 0.05.

Conclusion

The novel planning methodology using multiple shells including the novel OptiForR50 shell with precisely calculated dimensions and optimizer constraints lead to significantly lower values of R50% and D2cm and lower dose spillage in lung SBRT plans. All plans were successfully brought into the zone of no RTOG violations.
Development and clinical validation of a robust knowledge‐based planning model for stereotactic body radiotherapy treatment of centrally located lung tumors
Authors: Visak Justin , McGarry Ronald C. , Randall Marcus E. , Pokhrel Damodar
Published: December 2020

Purpose

To develop a robust and adaptable knowledge‐based planning (KBP) model with commercially available RapidPlanTM for early stage, centrally located non‐small‐cell lung tumors (NSCLC) treated with stereotactic body radiotherapy (SBRT) and improve a patient's“simulation to treatment” time.

Methods

The KBP model was trained using 86 clinically treated high‐quality non‐coplanar volumetric modulated arc therapy (n‐VMAT) lung SBRT plans with delivered prescriptions of 50 or 55 Gy in 5 fractions. Another 20 independent clinical n‐VMAT plans were used for validation of the model. KBP and n‐VMAT plans were compared via Radiation Therapy Oncology Group (RTOG)–0813 protocol compliance criteria for conformity (CI), gradient index (GI), maximal dose 2 cm away from the target in any direction (D2cm), dose to organs‐at‐risk (OAR), treatment delivery efficiency, and accuracy. KBP plans were re‐optimized with larger calculation grid size (CGS) of 2.5 mm to assess feasibility of rapid adaptive re‐planning.

Results

Knowledge‐based plans were similar or better than n‐VMAT plans based on a range of target coverage and OAR metrics. Planning target volume (PTV) for validation cases was 30.5 ± 19.1 cc (range 7.0–71.7 cc). KBPs provided an average CI of 1.04 ± 0.04 (0.97–1.11) vs. n‐VMAT plan'saverage CI of 1.01 ± 0.04 (0.97–1.17) (P < 0.05) with slightly improved GI with KBPs (P < 0.05). D2cm was similar between the KBPs and n‐VMAT plans. KBPs provided lower lung V10Gy (P = 0.003), V20Gy (P = 0.007), and mean lung dose (P < 0.001). KBPs had overall better sparing of OAR at the minimal increased of average total monitor units and beam‐on time by 460 (P < 0.05) and 19.2 s, respectively. Quality assurance phantom measurement showed similar treatment delivery accuracy. Utilizing a CGS of 2.5 mm in the final optimization improved planning time (mean, 5 min) with minimal or no cost to the plan quality.

Conclusion

The RTOG‐compliant adaptable RapidPlan model for early stage SBRT treatment of centrally located lung tumors was developed. All plans met RTOG dosimetric requirements in less than 30 min of planning time, potentially offering shorter “simulation to treatment” times. OAR sparing via KBPs may permit tumorcidal dose escalation with minimal penalties. Same day adaptive re‐planning is plausible with a 2.5‐mm CGS optimizer setting.
Design of 2D Layered Catalyst by Coherent Heteroepitaxial Conversion for Robust Hydrogen Generation
Authors: Sim Yeoseon , Yoon Aram , Kang Hee Seong , Kwak Jinsung , Kim Se‐Yang , Jo Yongsu , Choe Daeseong , Na Woongki , Lee Min Hee , Park Soon‐Dong , Song Seunguk , Kim Daeyong , Yoo Jung‐Woo , Kim Sung Youb , Cheong Hyeonsik , Lee Jae Sung , Lee Chul‐Ho , Lee Zonghoon , Kwon Soon‐Yong
Published: December 2020

The structural engineering of 2D layered materials is emerging as a powerful strategy to design catalysts for high‐performance hydrogen evolution reaction (HER). However, the ultimate test of this technology under typical operating settings lies in the reduced performance and the shortened lifespan of these catalysts. Here, a novel approach is proposed to design efficient and robust HER catalysts through out‐of‐plane deformation of 2D heterojunction using metal‐organic chemical vapor deposition. High‐yield, single‐crystalline WTe2 nanobelts are used as an epitaxial template for their coherent conversion to WS2. During the conversion process, the WTe2/WS2 heterostructure containing both lateral and vertical junctions are achieved by coherent heteroepitaxial stacking despite differences in symmetry. The lattice coherency drives out‐of‐plane deformation of heteroepitaxially grown WS2. The increase in the effective surface area and decrease in the electron‐transfer resistance across the 2D heterojunctions in turn enhances the HER performance as well as the long‐term durability of these electrocatalysts.
Metal Halide Scintillators with Fast and Self‐Absorption‐Free Defect‐Bound Excitonic Radioluminescence for Dynamic X‐Ray Imaging
Authors: Zhang Muyi , Wang Xiaoming , Yang Bo , Zhu Jinsong , Niu Guangda , Wu Haodi , Yin Lixiao , Du Xinyuan , Niu Ming , Ge Yongshuai , Xie Qingguo , Yan Yanfa , Tang Jiang
Published: December 2020

Scintillators for radiation detection are of great significance in medical imaging, security, and nondestructive inspection. The current challenge for scintillators is to simultaneously achieve high scintillation light yield, fast radioluminescence, simple film fabrication, large X‐ray attenuation efficiency as well as stable and nontoxic compositions; no previous scintillators fulfill all the above requirements. Here, metal halide Rb2AgBr3, possessing defect‐bound excitonic radioluminescence, is shown as efficient and fast scintillators. This nontoxic and stable scintillator emits from excitons bound to neutral bromine vacancies, enjoying an efficient and spin‐allowed fast emission with minimized self‐absorption. Rb2AgBr3 thus has a high light yield (25 600 photons MeV−1), fast scintillation decay time (5.31 ns), and a record value of light yield versus decay time (4821 photons MeV−1 ns−1). The close‐space sublimation method is developed for fast and scalable fabrication of oriented Rb2AgBr3 films. The scintillator film is further integrated with commercial flat‐panel imagers, and the spatial resolution reaches 10.2 line pairs per millimeter at the modulation transfer function of 0.2, doubling the resolution of conventional CsI:Tl flat‐panel detectors. The dynamic X‐ray imaging and its use to real‐time monitoring of bone movement without ghosting effect is also demonstrated.
Recent Progress of Vacancy Engineering for Electrochemical Energy Conversion Related Applications
Authors: Wu Zexing , Zhao Ying , Jin Wei , Jia Baohua , Wang Jie , Ma Tianyi
Published: December 2020

Efficient electrocatalysts are key requirements for the development of ecofriendly electrochemical energy‐related technologies and devices. It is widely recognized that the introduction of vacancies is becoming an important and valid strategy to promote the electrocatalytic performances of the designed nanomaterials. In this review, the significance of vacancies (i.e., cationic vacancies, anionic vacancies, and mixed vacancies) on the improvement of electrocatalytic performances via three main functionalities, including tuning the electronic structure, regulating the active sites, and improving electrical conductivity, is systematically discussed. Recent achievements in vacancy engineering on various hotspot electrocatalytic processes are comprehensively summarized, with focus on the oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), nitrogen reduction reaction (NRR), CO2 reduction reaction (CO2RR), and their further applications in overall water‐splitting and zinc–air battery devices. The recent development of vacancy engineering for other energy‐related applications is also summarized. Finally, the challenges and prospects of vacancy engineering to regulate the electrocatalytic performances of different electrochemical reactions are discussed.
Hammett Relationship in Oxidase‐Mimicking Metal–Organic Frameworks Revealed through a Protein‐Engineering‐Inspired Strategy
Authors: Wu Jiangjiexing , Wang Zhenzhen , Jin Xin , Zhang Shuo , Li Tong , Zhang Yihong , Xing Hang , Yu Yang , Zhang Huigang , Gao Xingfa , Wei Hui
Published: December 2020

While the unique physicochemical properties of nanomaterials that enable regulation of nanozyme activities are demonstrated in many systems, quantitative relationships between the nanomaterials structure and their enzymatic activities remain poorly understood, due to the heterogeneity of compositions and active sites in these nanomaterials. Here, inspired by metalloenzymes with well‐defined metal–ligand coordination, a set of substituted metal–organic frameworks (MOFs) with similar coordination is employed to investigate the relationship between structure and oxidase‐mimicking activity. Both experimental results and density functional theory calculations reveal a Hammett‐type structure–activity linear free energy relationship (H‐SALR) of MIL‐53(Fe) (MIL = Materials of Institute Lavoisier) nanozymes, in which increasing the Hammett σm value with electron‐withdrawing ligands increases the oxidase‐mimicking activity. As a result, MIL‐53(Fe) NO2 with the strongest electron‐withdrawing NO2 substituent shows a tenfold higher activity than the unsubstituted MIL‐53(Fe). Furthermore, the generality of H‐SALR is demonstrated for a range of substrates, one other metal (Cr), and even one other MOF type (MIL‐101). Such biologically inspired quantitative studies demonstrate that it is possible to identify quantitative structure–activity relationships of nanozymes, and to provide detailed insight into the catalytic mechanisms as those in native enzymes, making it possible to use these relationships to develop high‐performance nanomaterials.
Activatable NIR‐II Plasmonic Nanotheranostics for Efficient Photoacoustic Imaging and Photothermal Cancer Therapy
Authors: Zhou Chunyu , Zhang Liang , Sun Tao , Zhang Yang , Liu Yiding , Gong Mingfu , Xu Zhongsheng , Du Mengmeng , Liu Yun , Liu Gang , Zhang Dong
Published: December 2020

Precise manipulation of optical properties through the structure‐evolution of plasmonic nanoparticles is of great interest in biomedical fields including bioimaging and phototherapy. However, previous success has been limited to fixed assembled structures or visible–NIR‐I absorption. Here, an activatable NIR‐II plasmonic theranostics system based on silica‐encapsulated self‐assembled gold nanochains (AuNCs@SiO2) for accurate tumor diagnosis and effective treatment is reported. This transformable chain structure breaks through the traditional molecular imaging window, whose absorption can be redshifted from the visible to the NIR‐II region owing to the fusion between adjacent gold nanoparticles in the restricted local space of AuNCs@SiO2 triggered by the high H2O2 level in the tumor microenvironment (TME), leading to the generation of a new string‐like structure with strong NIR‐II absorption, which is further confirmed by finite‐difference‐time‐domain (FDTD) simulation. With the TME‐activated characteristics, AuNCs@SiO2 exhibits excellent properties for photoacoustic imaging and a high photothermal conversion efficiency of 82.2% at 1064 nm leading to severe cell death and remarkable tumor growth inhibition in vivo. These prominent intelligent TME‐responsive features of AuNCs@SiO2 may open up a new avenue to explore optical regulated nano‐platform for intelligent, accurate, and noninvasive theranostics in NIR‐II window.
Cathodoluminescence of Ultrathin Twisted Ge1–xSnxS van der Waals Nanoribbon Waveguides
Authors: Sutter Peter , Khorashad Larousse Khosravi , Argyropoulos Christos , Sutter Eli
Published: December 2020

Ultrathin van der Waals semiconductors have shown extraordinary optoelectronic and photonic properties. Propagating photonic modes make layered crystal waveguides attractive for photonic circuitry and for studying hybrid light–matter states. Accessing guided modes by conventional optics is challenging due to the limited spatial resolution and poor out‐of‐plane far‐field coupling. Scanning near‐field optical microscopy can overcome these issues and can characterize waveguide modes down to a resolution of tens of nanometers, albeit for planar samples or nanostructures with moderate height variations. Electron microscopy provides atomic‐scale localization also for more complex geometries, and recent advances have extended the accessible excitations from interband transitions to phonons. Here, bottom‐up synthesized layered semiconductor (Ge1–xSnxS) nanoribbons with an axial twist and deep subwavelength thickness are demonstrated as a platform for realizing waveguide modes, and cathodoluminescence spectroscopy is introduced as a tool to characterize them. Combined experiments and simulations show the excitation of guided modes by the electron beam and their efficient detection via photons emitted in the ribbon plane, which enables the measurement of key properties such as the evanescent field into the vacuum cladding with nanometer resolution. The results identify van der Waals waveguides operating in the infrared and highlight an electron‐microscopy‐based approach for probing complex‐shaped nanophotonic structures.
New Insight into the Doped Strontium Titanate Cathode with In Situ Exsolved Nickel Nanoparticles for Electrolysis of Carbon Dioxide
Authors: Bai Lu , Li Haibin , Yan Zhen , Hao Xiaohan , Ke Minghui , Xie Kui , Li Baoguang
Published: December 2020

One way to avoid CO2 pollution is changing it into CO by solid oxide electrolyzers, in which doped SrTiO3 can be used as cathode materials. It is found that in situ exsolved Ni nanoparticles in doped SrTiO3 cathode can further improve the electrolysis performance. In this work, (La0.2Sr0.8)0.85Ti0.8Cr0.1Ni0.1O3−δ cathode with in situ exsolved Ni particles is investigated. A new model proposed explains the influence of exsolution process on crystal structure. Based on thermogravimetric analysis, it is estimated that about 13.6% to 37.4% Ni atoms exsolve out of original cathode. With the new cathode containing Ni nanoparticles, the yield of CO from electrolysis is improved at about 50% and the current efficiency is increased at about 10%.
Trends in growth and developmental tempo in boys aged 7 to 18 years between 1966 and 2012 in Poland
Authors: Gomula Aleksandra , Nowak‐Szczepanska Natalia , Hermanussen Michael , Scheffler Christiane , Koziel Slawomir
Published: December 2020

Objectives

To assess trends in growth in different developmental periods and trends in developmental tempo in Polish boys between 1966 and 2012.

Methods

Data on 34 828 boys aged 7 to 18 years were collected during Polish Anthropological Surveys conducted in 1966, 1978, 1988, and 2012. Biological parameters, related to onset of adolescent growth spurt (OGS) and peak height velocity (PHV), were derived from a Preece‐Baines 1 model (PB1). Childhood (height at 7 years of age), pre‐adolescent (height at OGS) and adolescent growth (adult height minus height at OGS) were identified.

Results

Positive secular trend between 1966 and 2012 in adult height accounted for, on average, 1.5 cm/decade, with varying intensity between the Surveys. Decline in both age at OGS and APHV between 1966 and 2012 (1.5 and 1.4 years, respectively) indicated an acceleration in developmental tempo, on average, by 0.3 year/decade. Increases in the contribution to the trend in adult height gained during growth in particular developmental periods between 1966 and 2012 were as followed—childhood: 0.6%, pre‐adolescent growth: −3.1%, adolescent growth: 3.1%.

Conclusions

Secular trend in developmental tempo and growth among boys reflects changes in living conditions and socio‐political aspirations in Poland during nearly 50 years. Acceleration in tempo is already visible at age at OGS, whereas the trend in adult height occurs largely during adolescence, pointing to different regulation of developmental tempo and growth in body height. This finding emphasizes the importance of extending public health intervention into children's growth up until adolescence.
Qualitative analysis on needs of family caregivers for people with dementia
Authors: Ho‐yin Lai Frank
Published: December 2020

Background

Dementia is a public health challenge worldwide. Caring for a person with dementia affects different caregivers in different ways. The objective of this study was to explore the role caregivers (FCGs) for people with dementia play, along with their needs and the stress they experience, as a means of understanding their overall experience of caring. Second, to identify coping strategies employed by FCGs and to explore positive aspects of the caring relationship in relation to their quality of life, information needs, day care and respite care, and emotional support. Third, to develop a medical‐social collaboration model from socio‐ecological perspectives to provide support services to older adults with mild to moderate dementia and their FCGs at the community level.

Method

Different support groups for older adults with dementia include hospital caregivers’ support groups, district‐based dementia care networks, and community non‐government organizations participating in this project. Through four focus groups for FCGs, qualitative data were collected.

Result

From December 2018 to March 2019, 80 FCGs were recruited through purposeful sampling. They shared similar demographic and socio‐demographic backgrounds. Addressing the first two objectives involves exploring the role, needs, and stress of FCGs and identifying their coping strategies. Five major themes relating to FCGs’ experiences were identified through the focus groups on caregiving for older adults with dementia: a) seeking understanding, b) stabilization, c) preparation, d) implementation, and e) adaptation. In addressing the third objective, with reference to Bronfenbrenner’s Ecological Systems theory (Bronfenbrenner, 1977, Bronfenbrenner and Ceci, 1994), a medical‐social model was developed and to provide support services to FCGs at the community level. The facilitators and barriers identified by thematic analysis.

Conclusion

Many of the barriers and facilitators identified are echoed by findings from previous studies. Individuals’ needs must be integrated into future service planning and decision‐making processes.
Early candidate urine biomarkers for detecting Alzheimer’s disease before amyloid‐plaque deposition in an APP (swe)/PSEN1dE9 transgenic mouse model for effective early intervention
Authors: Zhang Fanshuang , Wei Jing , Li Xundou , Huan Yuhang , Ma Chao , Gao Youhe
Published: December 2020

Background

The identification of candidate biomarkers before amyloid‐ plaque deposition occurs is therefore of great importance for the early intervention of AD. Urine, which is not regulated by homeostatic mechanisms, theoretically accumulates changes associated with AD earlier than cerebrospinal fluid and blood. In this study, an APP (swe)/PSEN1dE9 transgenic mouse model was used to identify candidate biomarkers for early AD.

Method

Urine samples were collected from 4‐, 6‐, and 8‐month‐old transgenic mouse models, and the urinary proteomes were profiled using liquid chromatography coupled with tandem mass spectrometry (LC‐MS/MS). The pathways related to differential urinary proteins were analyzed. Early intervention was tested based on the pathway analysis.

Result

The levels of 29 proteins differed significantly between wild type and 4‐month‐old mice, which had not started to accumulate amyloid‐ plaques. Among these proteins, 13 have been associated with the mechanisms of AD, while 9 have been suggested as AD biomarkers. The result of intervention is promising. The details will be available before the meeting.

Conclusion

Our results indicated that urine proteins enable detection of AD before amyloid‐ plaque deposition, which may present an opportunity for effective intervention.
Serum 25‐hydroxyvitamin D, folate and cobalamin and their association with brain volumes and white matter integrity in a sample of urban adults
Authors: Beydoun May A , Shaked Danielle , Hossain Sharmin A , Beydoun Hind A , Katzel Leslie , Davatzikos Christos , Gullapalli Rao , Seliger Stephen , Erus Guray , Evans Michele K , Zonderman Alan , Waldstein Shari
Published: December 2020

Background

Lower vitamin D, folate and cobalamin status were linked to cognitive deficits, pending mechanistic elucidation. We explored whether serum 25‐hydroxyvitamin D [25(OH)D], folate and cobalamin are related to brain volumes and white matter (WM) integrity.

Method

Between 183 and 240 community‐dwelling participants [Baltimore city, Agev1: 30‐64y] had vitamin concentrations [at visit 1(v1)] and Magnetic Resonance Imaging (MRI) measures at follow‐up (vscan), after a mean±SD=5.70y±1.90. Multivariable‐adjusted linear regression analyses were conducted using structural and diffusion magnetic resonance imaging (sMRI/dMRI) with increasing segmentation specificity as outcomes and each vitamin as an exposure (v1 and annual rate of change (v2‐v1) over an average of 4.65y), stratifying by agev1 (>50y/≤50y), sex, race (Whites/African Americans) and poverty status group. Top 10 ranked adjusted associations were statistically significant if passing familywise Bonferroni (FWER) criteria at an α=0.05, while false discovery rates (FDR, q‐value)<0.10 and standardized effect size (b) criteria were used for trend findings.

Result

We found mostly significant (FWER<0.05) direct associations of 25(OH)D(v1) with WM volumes (overall/males), with occipital and parietal WM [overall, males and Agev1>50y], and with the left occipital pole volume. Folate(v1), 25(OH)D(v1) and 25(OH)D(v2‐v1) trended towards better WM integrity in several regions, mainly the anterior limb of the internal capsule (ALIC) and the hippocampus [q<0.10 per vitamin, b≥0.20 for 25(OH)D(v1) and Folate(v1); FWER<0.05 for 25(OH)D(v2‐v1)], while folate trended towards lower right temporal pole volume (Whites/>50y) and longitudinal increase (v2‐v1) in cobalamin trended towards larger volumes within the inferior frontal gyrus.

Conclusion

Serum 25(OH)D was consistently linked to greater occipital and parietal WM volumes. WM integrity in ALIC was associated with higher 25(OH)D and folate status, while folate was inversely related to temporal GM volumes. Cobalamin increase over time trended towards larger inferior frontal gyrus volumes. Future interventions should test vitamin supplementation against regional volumetric and diffusion brain markers.
Supporting people with dementia and their caregivers’ everyday occupations through home hazard identification and virtual reality‐based training
Authors: Ho‐yin Lai Frank
Published: December 2020

Background

Falls are a common health hazard among older people and have become a major cause of disability. The risk of falling increases with age and many older people need extended hospital stays as a result of a fall, and some may be admitted to residential care after a fall. The interaction between the older adults with dementia, their living environment and fall is an area of concern from occupational therapy.

Method

This is a pioneer study composed of a home falls and accident screening and with two types of intervention in a 12‐month longitudinal randomized controlled trial. In the first month, participants received the psychoeducation program on home safety and fall prevention in their own home. Then for the following eleven months, participants were randomized to either control group which participants will receive bi‐weekly reviews of home safety and fall prevention. Experimental group will have regular training on the use of VR‐based home safety alertness for near miss.

Result

100 community dwelling moderate dementia subjects (CDR> 2) were recruited, 25 of them reported with five or more home hazards and labelled as high risk group. 32% of subjects reported with hazards which labelled as “Home Environment and Furniture”, 28% of recruited population reported with hazards in “Capability in Activities of Daily Living” and 32 % reported with hazards in “Use of devices”. In one‐year follow‐up, both experimental group showed significantly lower incidence of fall of 5 % when compared with 18% in general dementia population.

Conclusion

Results indicated home safety and fall prevention screening is effective to reduce home hazards. Application of VR can be a reinforcing strategy for people with dementia and can help alleviate stress of caregivers.