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There has been growing interest in employing metal–organic frameworks (MOFs) incorporated with biomolecules, known as b-MOFs, in biomedical applications.

Ganoderma multipileum was initially discovered in Taiwan as a wood decay fungus on many host plants. However, the detailed taxonomy of this genus has suffered from a lack of in-depth investigation. In this study, the classification of these fungi was described based on their morphology, the phylogeny of three regions (ITS, RPB2, and TEF1 sequences), and the assessment of scanning electron microscope photographs of basidiospores. In addition, the similarities and differences in the characteristics of this mushroom in comparison to related species were analyzed and discussed from morphological and phylogenetic perspectives. The results indicate that G. multipileum was newly recorded in Vietnam, and its relation to ornamental plant die-back is noted.

The internal capital adequacy and assessment process (ICAAP) was first introduced in the second pillar of Basel II in 2004 to offset the deficiencies of Basel I and capital adequacy regulations in the first pillar of Basel II. This process is aimed at identifying and measuring risks generated in banks’ activities, and then provides the requirements for internal capital levels and methods to raise capital to deal with these risks. In fact, the implementation of Basel II and ICAAP in Vietnamese commercial banks has attained notable achievements, but it also revealed some major weaknesses. The purpose of this research is to evaluate the implementation of ICAAP in Vietnamese commercial banks in eight components of the ICAAP addressed by Basel II using the survey method and then to simulate the implementation of ICAAP in a Vietnamese commercial bank. From the facts and the simulation of the ICAAP framework in this study, the authors offer some suggestions for Vietnamese commercial banks to implement ICAAP effectively in their banking operations.

Antibacterial materials have been developed for a long time but bacteria adapt very quickly and become resistant to these materials. This study focuses on the synthesis of a hybrid material system from lignin and silver/silica nanoparticles (Lig@Ag/SiO

Background: Staphylococcus aureus is a nosocomial pathogen responsible for many serious infectious diseases in humans. Finding the anti- S. aureus agents is a time-consuming and costly process. Recently, computational methods have provided a better understanding of the interactions between herbal medicine drug targets to help clinical practitioners rationally design herbal formulae. Methods: In this study, molecular docking simulation was applied to screen a list of natural secondary metabolites from Ganoderma sp. on the protein target S. aureus sortase A. Molecular dynamics models were used to assess the stability of protein–ligand complexes during the first 100 ns. To validate the computational results, 2 Ganoderma species, G. multiplicatum VNKKK1901 and G. sinense VNKKK1902, were tested for antibacterial activity against S. aureus using the disk diffusion method. Results: The results showed that, among the selected compounds, ganosinensin B and ganosinoside A generated the highest binding energy on S. aureus sortase A, and demonstrated strong and stable binding capacity to proteins. In addition, the extracts of G. sinense VNKKK1902 and G. multiplicatum VNKKK1901 were bactericidal, with minimum bactericidal concentration (MBC)/minimum inhibitory concentration (MIC) ratios of 2. Conclusion: Our findings provide the first scientific report on the antibacterial activity of Ganoderma sp., which contain 2 promising compounds, ganosinensin B and ganosinoside A, as potential hits for developing novel drugs capable of supporting treatment of S. aureus infection.

International audience; Recently, treatment advances in direct-acting antivirals have radically changed the management of HCV patients. However, in resource-limited countries, identification of patients with active HCV infection is still challenging in remote settings due to the limited access to laboratories able to measure HCV viral load. This study evaluated whether dried blood spots (DBS) transferred to a central laboratory could overcome this challenge. A total of 315 HCV-infected patients, naïve to anti-HCV treatment, provided each three type of samples: plasma, DBS with calibrated quantities of venous blood and DBS with uncalibrated quantities of capillary blood. Qualitative comparison was conducted in terms of detection of HCV viral load on DBS as opposed to plasma to estimate sensitivity and specificity. Quantitative comparisons were conducted by means of correlation estimation. Of the 250 patients with detected plasma HCV viral load, 245 also had detectable DBS HCV viral load (capillary or venous) leading to a sensitivity of 98.0% (95% confidence interval (CI): 95.4%-99.3%); importantly, all measurements with a plasma HCV viral load >118 IU/mL were also detected in DBS. When HCV was not detected in plasma, it was also not detected in DBS resulting in 100% specificity (95% CI: 94.5%-100%). Quantitative HCV viral load results were very similar when utilizing plasma or DBS sample types as illustrated by correlations >0.99. In conclusion, DBS sample types, with either uncalibrated capillary blood or calibrated venous blood, performed well to distinguish patients with active HCV infection, and who therefore need treatment, from other patients.

The long stagnation of the photo-conversion efficiency of kesterites below 13% is a source of frustration in the scientific community. In this study, we investigated the effects of sodium on the passivation of grain boundaries and defects in Cu2ZnSnSe4 (CZTSe) grown on a soda-lime glass (SLG) and borosilicate (BS) glass. Because BS glass does not inherently contain sodium, we placed a thin layer of NaF between CZTSe and Mo. The composition of the samples is Cu-poor and Zn-rich. The distribution of sodium and its contributions to phase formation and defects were examined by cross-sectional energy-dispersive X-ray profiling, Raman scattering spectroscopy and imaging, surface potential and photoluminescence. From the experimental results, it can be strongly claimed that sodium ions segregate predominantly near the grain boundaries and reduce CuZn-related defects. These local surface imaging analyses provided the exact locations of the secondary phases. In particular, the photo-assisted scanning probe method enabled us to observe the changes in the optoelectrical properties of the thin films and the carrier behavior within the materials. Further studies with distinct alkali ions and optimal processing conditions will pave a way to improve the performance of kesterite solar cells.

In this study, chitosan and alginate were selected to prepare alginate/chitosan nanoparticles to load the drug lovastatin by the ionic gelation method. The synthesized nanoparticles loaded with drug were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), laser scattering and differential scanning calorimetry (DSC) methods. The FTIR spectrum of the alginate/chitosan/lovastatin nanoparticles showed that chitosan and alginate interacted with lovastatin through hydrogen bonding and dipolar-dipolar interactions between the C-O, C=O, and OH groups in lovastatin, the C-O, NH, and OH groups in chitosan and the C-O, C=O, and OH groups in alginate. The laser scattering results and SEM images indicated that the alginate/chitosan/lovastatin nanoparticles have a spherical shape with a particle size in the range of 50–80 nm. The DSC diagrams displayed that the melting temperature of the alginate/chitosan/lovastatin nanoparticles was higher than that of chitosan and lower than that of alginate. This result means that the alginate and chitosan interact together, so that the nanoparticles have a larger crystal degree when compared with alginate and chitosan individually. Investigations of the in vitro lovastatin release from the alginate/chitosan/lovastatin nanoparticles under different conditions, including different alginate/chitosan ratios, different solution pH values and different lovastatin contents, were carried out by ultraviolet-visible spectroscopy. The rate of drug release from the nanoparticles is proportional to the increase in the solution pH and inversely proportional to the content of the loaded lovastatin. The drug release process is divided into two stages: a rapid stage over the first 10 hr, then the release becomes gradual and stable. The Korsmeyer-Peppas model is most suitable for the lovastatin release process from the alginate/chitosan/lovastatin nanoparticles in the first stage, and then the drug release complies with other models depending on solution pH in the slow release stage. In addition, the toxicity of alginate/chitosan/lovastatin (abbreviated ACL) nanoparticles was sufficiently low in mice in the acute toxicity test. The LD50 of the drug was higher than 5000 mg/kg, while in the subchronic toxicity test with treatments of 100 mg/kg and 300 mg/kg ACL nanoparticles, there were no abnormal signs, mortality, or toxicity in general to the function or structure of the crucial organs. The results show that the ACL nanoparticles are safe in mice and that these composite nanoparticles might be useful as a new drug carrier.

The aim of this study was to investigate the adsorption of three commercial reactive dyes using extracellular polymeric substances (EPS) extracted from the waste sludge of a beer wastewater treatment plant in Hanoi, Vietnam. EPS was extracted from sludge by HCHO-NaOH method and characterized by the measurement of kaolin flocculation activity, dry weight, chemical composition and functional groups. Adsorption of dyes on EPS was conducted by Jartest at different pH, reaction time and EPS dosage. The EPS was composed of 25% of sludge weight. The FTIR analysis showed the present of amine and carboxyl group in the EPS structure. The removal efficiencies of reactive dyes were high at pH below 6, the contact time was from 30 to 60 min and EPS dosage of 200 – 250 mg/L. At optimum condition, the removal efficiency of 85%, 99% and 99% were obtained for Reactive Yellow 176 (RY 176), Reactive Blue 21 (RB 21) and Reactive Red 241 (RR 241), respectively. The adsorption process could be described by both Langmuir and Fruendlich isothermal equations. The maximum dye adsorption capacity for RY 176, RB 21 and RR 241 was 0.50 g/g, 0.72 g/g and 0.95 g/g, respectively. This study revealed that the EPS in wastewater sludge can be utilized as an effective adsorbent for dyes removal, thereby, enhancing the value of sludge in wastewater treatment.

Background Patient-prosthesis mismatch (PPM) is a major concern in aortic valve replacement (AVR) and leads to perioperative morbidity and rehospitalization. Predicting aortic annulus diameter pre-procedurally is crucial to managing patients with high-risk of PPM. Objectives To compare preoperative measurements of aortic annulus from echocardiography and CT scan with surgical sizing and develop an imaging-based algorithm to predict PPM. Methods From January 2017 to December 2020, patients underwent AVR at a teaching hospital were examined. The relationship between imaging measurements with operative values was assesed using scatter plots and Pearson’s correlation coefficient. Univariable linear regression was then used to build the predictive model. Results A total of 144 patients underwent AVR during the study period. Suture types and surgical approaches were not significantly associated with prosthesis size. CT scan-based measurements showed strong correlation with prosthesis size: mean diameter (R = 0.79), perimeter-derived diameter (R = 0.76), and area-derived diameter (R = 0.75). Mechanical valve and tissue valve shared similar correlation coefficients. Prosthesis size predictive models based on CT scan were 12.89 + 0.335 × d for mean diameter, 13.275 + 0.315 × d for perimeter-derived diameter and 13.626 + 0.309 × d for area-derived diameter. Conclusions Preoperative CT scan measurements are a reliable predictor of aortic prosthesis size. Transthoracic echocardiography is a possible alternative, though it is highly performer-dependent and unable to represent the aortic annulus fully. Together, these two imaging modalities can be used to quantitatively anticipate PPM preoperatively.

Lactate accumulates to a significant amount in glioblastomas (GBMs), the most common primary malignant brain tumor with an unfavorable prognosis. However, it remains unclear whether lactate is metabolized by GBMs. Here, we demonstrated that lactate rescued patient-derived xenograft (PDX) GBM cells from nutrient-deprivation-mediated cell death. Transcriptome analysis, ATAC-seq, and ChIP-seq showed that lactate entertained a signature of oxidative energy metabolism. LC/MS analysis demonstrated that U

While conducting rotavirus gastroenteritis surveillance in Vietnam, two G3P[8] rotavirus A specimens possessing an identical short RNA electropherotype were detected. They were RVA/Human-wt/VNM/0232/2016/G3P[8] and RVA/Human-wt/VNM/0248/2016/G3P[8], and recovered from 9 and 23 months old boys, respectively. The patients developed diarrhoea within one-week interval in March 2016 but in places >100 km apart in northern Vietnam. Whole genome sequencing of the two G3P[8] rotavirus A strains revealed that their genomic RNA sequences were identical across the 11 genome segments, suggesting that they derived from a single clone. The backbone gene constellation was I2-R2-C2-M2-A2-N2-T2-E2-H2. The backbone genes and the VP4 gene had a virtually identical nucleotide sequences with identities ranging from 99.2 to 100% to the corresponding genes of RVA/Human-wt/VNM/1149/2014/G8P[8]; the prototype of recently-emerging bovine-like G8P[8] reassortant strains in Vietnam. On the other hand, the VP7 gene was 98.8% identical with that of RVA/Human-wt/CHN/E2451/2011/G3P[9], and they were clustered together in the lineage represented by RVA/Cat-tc/JPN/FRV-1/1986/G3P[9]. The observations led us to hypothesise that one of the bovine-like G8P[8] strains bearing the DS-1-like backbone genes reassorted with a locally circulating FRV-1-like strain to gain the G3 VP7 gene and to emerge as a thus-far undescribed feline-like G3P[8] reassortant strain. The identification of feline-like G3P[8] strains bearing the DS-1-like backbone genes exemplifies the strength and necessity of the whole genome sequencing approach in monitoring, describing and understanding the evolutionary changes that are occurring in emerging strains and their interactions with co-circulating strains.

The perovskite layer is the most crucial factor for the high performance tin-based perovskite. Herein, we investigate the effect of solvent on the morphology of perovskite films systematically. Dimethyl sulfoxide (DMSO) has been adopted as a high boiling point combined with the commonly used N,N-dimethylformamide (DMF) to control the rapid nucleation and retarding crystal growth. A pinhole-free MASnI3 perovskite film with dense and large grains is obtained. By optimizing the solvent composition, multiple tin-based mixed iodine and bromine perovskite solar cells (MASn(I1−xBrx)3 0 ≤ x ≤ 1) were fabricated. The best photoconversion cell efficiency was obtained at x = 0.67, which yields to 3.20% compared to the original MASnI3 (1.17%) due to the benefit band level alignment. The conductivity and the stability of the MASn(I1−xBrx)3 perovskite device was carefully studied.

This research aims to evaluate the influence of different 3D metals (Fe, Co, and Ni) substituted to Mn on the electrochemical performance of P2-NaxMe1/3Mn2/3O2 material, which was synthesized by the coprecipitation process followed by calcination at high temperature. X-ray diffraction (XRD) results revealed that the synthesized Mn-rich materials possessed a P2-type structure with a negligible amount of oxide impurities. The materials possessed their typical cyclic voltammogram and charge-discharge profiles; indeed, a high reversible redox reaction was obtained by NaxCo1/3Mn2/3O2 sample. Both NaxCo1/3Mn2/3O2 and NaxFe1/3Mn2/3O2 provided a high specific capacity of above 140 mAh·g−1; however, the former showed better cycling performance with 83% capacity retention after 50 cycles at C/10 and high rate capability. Meanwhile, the Ni-sub NaxNi1/3Mn2/3O2 exhibited excellent cycling stability but a low specific capacity of 110 mAh·g−1 and inferior rate capability. The diffusion coefficient of Na+ ions into the structure tended to decrease with a depth of discharge; those values were in the range of 10−10–10−9 cm2·s−1 and 10−11–10−10 cm2·s−1 in the solid solution region and biphasic region, respectively.

Methylammonium lead trihalide perovskites CH

The long stagnation of the photo-conversion efficiency of kesterites below 13% is a source of frustration in the scientific community. In this study, we investigated the effects of sodium on the passivation of grain boundaries and defects in Cu

Dengue virus (DENV) replication between mosquito and human hosts is hypothesized to be associated with viral determinants that interact in a differential manner between hosts. However, the understanding of inter-host viral determinants that drive DENV replication and growth between hosts is limited. Through the use of clinical isolates, we identified an amino acid variation of Ala, Met and Val at position 116 of DENV-1 NS4B. While the proportion of virus with the NS4B-116V variant remained constantly high in serial passages in a mosquito cell line, populations of the NS4B-116M and NS4B-116A variants became dominant after serial passages in mammalian cell lines. Using recombinant DENV-1 viruses, the Val to Ala or Met alteration at position NS4B-116 (rDENV-1-NS4B-116A and rDENV-1-NS4B-116M) resulted in enhanced virus growth in human cells in comparison to the clone with Val at NS4B-116 (rDENV-1-NS4B-116V). However, the reverse phenomenon was observed in a mosquito cell line. Additionally, in a human cell line, differential levels of IFN-α/β and IFN-stimulated gene expressions (IFIT3, IFI44L, OAS1) suggested that the enhanced viral growth was dependent on the ability of the NS4B protein to hamper host IFN response during the early phase of infection. Overall, we identified a novel and critical viral determinant at the pTMD3 of NS4B region that displayed differential effects on DENV replication and fitness in human and mosquito cell lines. Taken together, the results suggest the importance of the NS4B protein in virus replication and adaptation between hosts.

According to the so-called upwelling paradigm, development of equatorial plasma bubbles (EPBs) involves (1) appearance of an upwelling (i.e., local uplift with a zonal width of ~ 400 km) in the bottomside of the equatorial F layer, (2) its growth via the F-region interchange instability during the post-sunset rise (PSSR) of the F layer, and (3) launching of EPBs, which starts near the end of PSSR, from within the confines of the upwelling. In this description, the PSSR is presumed to be the primary driver of the paradigm, with upwelling growth dependent on PSSR strength. As constructed, the paradigm describes EPB development when PSSR is strong (i.e., high solar activity), but not when it is weak. We, show, for the first time, that when PSSR is weak (e.g., low solar activity), upwelling growth can still be comparable in strength to what would be considered a strong PSSR, and that this growth drives EPB development. Given that EPBs do not develop outside of upwellings, regardless of solar activity, we are led to conclude, against mainstream thinking, that the controlling driver for EPB development is upwelling growth, not PSSR. For continued progress toward understanding EPB development, a crucial next step is to identify the source mechanism for upwelling growth, especially when PSSR is weak, and to better understand the complexities of the underlying physics.

Heterostructures enable the control of transport and recombination of charge carriers, which are either injected through electrodes, or created by light illumination. Instead of full 2D-material-heterostructures in device applications, using hybrid heterostructures consisting of 2D and 3D materials is an alternative approach to take advantage of the unique physical properties of 2D materials. In addition, 3D dielectric nanostructures exhibit useful optical properties such as broadband omnidirectional antireflection effects and strongly concentrated light near the surface. In this work, the optical properties of 2D MoS2 monolayers conformally coated on 3D Si-based nanocone (NC) arrays are investigated. Numerical calculations show that the absorption in MoS2 monolayers on SiO2 NC is significantly enhanced, compared with that for MoS2 monolayers on Si NC. The weak light confinement in low refractive index SiO2 NC leads to greater absorption in the MoS2 monolayers. The measured photoluminescence and Raman intensities of the MoS2 monolayers on SiO2 NC are much greater than those on Si NC, which supports the calculation results. This work demonstrates that 2D MoS2-3D Si nano-heterostructures are promising candidates for use in high-performance integrated optoelectronic device applications.

Organic–inorganic lead halide perovskites have drawbacks in applications due to insufficient and inadequate understanding of the materials. In particular, it is a priority to investigate CH3NH3PbI3 due to its suitable properties and its band gap energy of about 1.59 eV. In this work, we investigated the perovskite crystal with respect to structural, electronic, and optical properties because a single crystal is an ideal platform for examining essential characteristics. The spatial distribution of the perovskite structure was identified by transmission electron microscopy and Kelvin probe force microscopy. The built electronic structure is an important index for the carrier types depending on the surface potential distribution. In particular, a potential variation showed a mixture of the perovskite phase and a decomposed phase on the surface, which also implied the role of surface imperfections as initiation sites for degradation. Therefore, it is critical to verify the carrier types on the surface to enhance the possibilities of improvements for applications.

Hybrid lead halide perovskite possesses attractive properties and outstanding performance. The electronic structure of hybrid lead halide perovskite single crystal can be used to comprehend its intrinsic properties. In this study, the crystal structure of CH3NH3PbBr3 perovskite crystal was elucidated by transmission electron microscopy. Phonon modes and CH3NH3+ rocking modes were analyzed. Band gaps of the crystal were obtained by temperature-dependent Raman scattering spectroscopy and photoluminescence measurement. Surface potential measurement for a (001) plane exhibited a work function of the material and other phases of PbBr2 and CH3NH3Br. From experimentally determined values, an electronic structure of CH3NH3PbBr3 was built. It showed a p-type characteristic.

This paper aims to discuss the competitiveness of safe vegetables of Ho Chi Minh City (HCMC). We employed Exploratory Factors Analysis and Regression Analysis methods on data collected from a survey of 150 respondents in Binh Chanh and Cu Chi districts. The results indicate that factors affecting the competitiveness of HCMC’s safe vegetables are price, packing, quality, diversity, flexibility and distribution system. The paper also offers three policy suggestions, namely 1) expanding scale and reducing costs to decrease the price HCMC’s safe vegetables; 2) improving the quality of HCMC’s safe vegetables; 3) diversifying types of HCMC’s safe vegetables.

There has been growing research interest in realizing optoelectronic devices based on the two-dimensional atomically thin semiconductor MoS2 owing to its distinct physical properties that set it apart from conventional semiconductors. However, there is little optical absorption in these extremely thin MoS2 layers, which presents an obstacle toward applying them for use in high-efficiency light-absorbing devices. We synthesized trilayers of MoS2 directly on SiO2/Si nanocone (NC) arrays using chemical vapor deposition and investigated their photodetection characteristics. The photoresponsivity of the MoS2/NC structure was much higher than that of the flat counterpart across the whole visible wavelength range (for example, it was almost an order of magnitude higher at λ = 532 nm). Strongly concentrated light near the surface that originated from a Fabry–Perot interference in the SiO2 thin layers and a Mie-like resonance caused by the Si NCs boosted the optical absorption in MoS2. Our work demonstrates that M...

VO2 thin films were grown on a-, c-, m-, and r-plane sapphire and SiO2/Si substrates under identical conditions by using RF sputtering deposition from a VO2 target. The structural and the morphological properties of all VO2 films were investigated. The grain sizes of the VO2 films varied between 268 nm and 355 nm depending on the substrate’s orientation. The electrical and the optical properties of all VO2 thin films were examined in detail. The metal-insulator transition temperature (TMI) varied with the substrate’s orientation. The (200)/( $$\bar 211$$ )-oriented VO2 films on the a-plane sapphire showed the lowest TMI of about 329.3 K (56.3 °C) while the (020)/(002)-VO2 films on the c-plane sapphire displayed the highest TMI of about 339.6 K (66.6 °C). The VO2 films showed reversible changes in the resistivity as large as 1.19 × 105 and a hysteresis of ~2 K upon traversing the transition temperature. The variations observed in the TMI with respect to the substrate’s orientation were due to changes in the lattice strain and the grain size distribution. Raman spectroscopy showed that metal (rutile) - insulator (monoclinic) transitions occurred via the M2 phase for VO2 films on the c-plane substrate rather than the direct M1 to rutile transition. The shifts in the phonon frequencies of the VO2 film grown on various sapphire substrates were explained in terms of the strain along the V-V atomic bond direction (cR). Our work shows a possible correlation between the transition parameters (e.g., TMI, sharpness, and hysteresis width) and the width (σ) of the grain size distribution. It also shows a possible correlation between the TMI and the resistivities at the insulating and the metallic phases for VO2 films grown on various sapphire substrates.

While conducting sentinel surveillance of hand, foot, and mouth disease (HFMD) in Vietnam, we found a sudden increase in the prevalence of coxsackievirus A10 (CV-A10) in 2016 and CV-A2 and CV-A4 in 2017, the emergence of which has been reported recently to be associated with various clinical manifestations in other countries. However, there have been only a limited number of molecular studies on those serotypes, with none being conducted in Vietnam. Therefore, we sequenced the entire VP1 genes of CV-A10, CV-A4, and CV-A2 strains associated with HFMD in Vietnam between 2012 and 2017. Phylogenetic analysis revealed a trend of endemic circulation of Vietnamese CV-A10, CV-A4, and CV-A2 strains and the emergence of thus-far undescribed HFMD-causing lineages of CV-A4 and CV-A2. The Vietnamese CV-A10 strains belonged to a genotype comprising isolates from patients with HFMD from several other countries; however, most of the Vietnamese strains were grouped into a local lineage. Recently, emerging CV-A4 strains in Vietnam were grouped into a unique lineage within a genotype comprising strains isolated from patients with acute flaccid paralysis from various countries. New substitutions were detected in the putative BC and HI loops in the Vietnamese CV-A4 strains. Except for one strain, Vietnamese CV-A2 isolates were grouped into a unique lineage of a genotype that includes strains from various countries that are associated with other clinical manifestations. Enhanced surveillance is required to monitor their spread and to specify their roles as etiological agents of HFMD or "HFMD-like" diseases, especially for CV-A4 and CV-A2. Further studies including whole-genome sequencing should be conducted to fully understand the evolutionary changes occurring in these newly emerging strains.

CH3NH3PbCl3 (MAPbCl3) perovskite single crystal is attractive for the ultra-violet detector due to its wide bandgap and comparative stability over iodine or bromine systems. Single crystals of MAPbCl3 perovskite are also intriguing owing to its generic type of materials for fundamental photophysical properties and excitonic behaviors for its use in devices. Furthermore, recent progress using crystal-based device fabrication will shed light on semiconducting devices like III–V compounds. In this study, a structurally well-defined crystal is grown and examined to reveal free and bound excitonic behaviors depending on the structural phase transition. We classified the free and bound excitonic behaviors by temperature- and power density-dependent photoluminescence and optical transmission spectra. The single emission peak located at 3.1 eV and blueshift depending on decreasing the temperature is attributed to the radiative recombination of the free exciton at the cubic and the tetragonal phases, whereas the several peaks from the bound excitonic transition are just revealed under 120 K of the orthorhombic phase. We also determined the work function distribution and band structures with excitonic bound states via Kelvin probe force microscopy. The optoelectronic properties resulted in the excitonic behaviors can be a fundamental approach for the construction of perovskite-based optoelectronic and photonic applications.

An apparently single rotavirus A strain possessing a genotype constellation of G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2 abruptly emerged, caused diarrhoea in children requiring hospitalisation, and increased to reach 27 % of strains detected during the first half of 2015 in Vietnam.