Facile Fabrication of SERS Substrates by the Electrodeposition Method to Detect Pesticides with High Enhancement Effect and Long-Term Stability.

In this study, surface-enhanced Raman scattering substrates were investigated by the electrodeposition method to detect low concentrations of pesticides via the electrodeposition method with different agents from silver and gold precursors on APTES-modified ITO glass. A dual-potential method supplied three electrodes and was performed with a nucleation potential of 0.7 V for 2 s and a growth potential of -0.2 V for 500 s. The Ag film produced by the electrodeposition approach has great surface uniformity and good SERS signal amplification for the thiram insecticide at low concentrations. Interestingly, the ITO/APTES/Ag substrate extensively increased the sensitivity than the other investigated ones, thanks to the adequate assistance of amino groups of APTES in the denser and hierarchical deposition of Ag NPs. These observations were additionally elucidated via finite-difference time-domain (FDTD) calculation. For thiram, the detection was set at 10-8 M with an enhancement factor of up to 3.6 × 107 times. Comparing the SERS spectra of thiram at concentrations of 10-3, 10-4, and 10-5 M with a relative standard deviation (RSD) of less than 7.0% demonstrates excellent reproducibility of the ITO/APTES/Ag substrate. In addition, the special selectivity of the ITO/APTES/Ag substrate for thiram demonstrates that these nanostructures can identify pesticides with extreme sensitivity.

Equilibria of semi-volatile isothiazolinones between air and glass surfaces measured by gas chromatography and Raman spectroscopy.

Trace amounts of semi-volatile organic compounds (SVOCs) of the two isothiazolinones of 2-methylisothiazol-3(2H)-one (MIT) and 2-octyl-4-isothiazolin-3-one (OIT) were detected both in the air and on glass surfaces. Equilibria of SVOCs between air and glass were examined by solid phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS). Surface to air distribution ratios of Ksa for MIT and OIT were determined to be 5.10 m and 281.74 m, respectively, suggesting more abundant MIT in the gas phase by a factor of ∼55. In addition, a facile method of silver nanocube (AgNC)-assisted surface-enhanced Raman scattering (SERS) has been developed for the rapid and sensitive detection of MIT and OIT on glass surfaces. According to MIT and OIT concentration-correlated SERS intensities of Raman peaks at ∼1585 cm-1 and ∼1125 cm-1, respectively. Their calibration curves have been obtained in the concentration ranges between 10-3 to 10-10 M and 10-3 to 10-11 M with their linearity of 0.9986 and 0.9989 for MIT and OIT, respectively. The limits of detection (LODs) of the two isothiazolinones were estimated at 10-10 M, and 10-11 M for MIT and OIT, respectively. Our results indicate that AgNC-assisted SERS spectra are a rapid and high-ultrasensitive method for the quantification of MIT and OIT in practical applications. The development of analytical methods and determination of the Ksa value obtained in this study can be applied to the prediction of the exposure to MIT and OIT from various chemical products and dynamic behaviors to assess human health risks in indoor environments.

Microalgae-enhanced bioremediation of Cr(VI) ions using spent coffee ground-derived magnetic biochar MoS2-Ag composites.

Composites of magnetic biochar derived from spent coffee grounds were prepared using MoS2 decorated by plasmonic silver nanoparticles (MoS2-Ag), which were used for the bioremediation Cr6+ ions. The composites were characterized by electron microscopy, X-ray diffraction, Raman, and UV-VIS spectroscopy. The bioremediation of Cr6+ ions was enhanced almost two times compared to microalgae, Spirulina maxima. Such an increased activity is attributed to heterojunction formation of Biochar@MoS2-Ag composite due to the synergetic effects of surface plasmon resonance of AgNPs inducing amplified local electric field, thus simultaneously increasing the absorption of MoS2 under visible or near-infrared light. The combination of Biochar@MoS2-Ag and Spirulina maxima powder was effective for the separation (microalga-based absorption and accumulation of Cr6+ ions) of photo-induced carriers (composite-assisted to breakdown Cr6+ ions). This study offers efficient eco-friendly treatment of Cr6+ ions by reporting the first enhanced bioremediation of Cr(VI) ions by microalgae using MoS2-Ag-modified biochar obtained from consumed coffee grounds.

Plans for Nationwide Serosurveillance Network in Vietnam.

In recent years, serosurveillance has gained momentum as a way of determining disease transmission and immunity in populations, particularly with respect to vaccine-preventable diseases. At the end of 2017, the Oxford University Clinical Research Unit and the National Institute of Hygiene and Epidemiology held a meeting in Vietnam with national policy makers, researchers, and international experts to discuss current seroepidemiologic projects in Vietnam and future needs and plans for nationwide serosurveillance. This report summarizes the meeting and the plans that were discussed to set up nationwide serosurveillance in Vietnam.

Bimetallic Thin-Film Combination of Surface Plasmon Resonance-Based Optical Fiber Cladding with the Polarizing Homodyne Balanced Detection Method and Biomedical Assay Application.

In this work, we present the optical birefringence properties of the optical fiber cladding that exists as an evanescent field where the refractive index (RI) of the analysis solution is applied for optical sensor aspiration. To enhance the performance of the sensor, we have investigated the sensor with different thicknesses of TiO2 coating and bimetallic (Ag-Al) film alloy combinations by thermal evaporation coating. We described a special balanced homodyne detection method for the intensity difference change between the p- and s-polarization lights in the surface plasmon resonance sensing systems, which is strongly determined by the RI of the test medium. The plasmonic optical fiber can measure a very small change of the RI of a glycerol solution, which is a resolution of 4.37 × 10-8 RI unit (RIU). This method has great advantages of a small-sized optical setup, high stability, high selectivity, easy chemical modification, and low cost. Furthermore, because of the experiment results, we observe that our approach can also eliminate the surrounding noise in the Mach-Zehnder interferometer, which shows the feasibility of this proposed technique. We demonstrate the fluorescence enhancement in detecting the C-reactive protein antibody conjugated with fluorescein isothiocyanate by means of near-field coupling between surface plasmons and fluorophores at spectral channels of emission. This technique can also be extended for application in a biomedical assay and in biochemical science, including molecular diagnostics relying on multichannels that require a small volume of the analyte at each channel which would suffer from the weakness of fluorescence if it were not for the enhancement technology.

A Systematic Review and Meta-analysis of Ventilator-associated Pneumonia in Adults in Asia: An Analysis of National Income Level on Incidence and Etiology.

Background: Ventilator-associated pneumonia (VAP) is the commonest hospital-acquired infection (HAI) in intensive care. In Asia, VAP is increasingly caused by resistant gram-negative organisms. Despite the global antimicrobial resistance crisis, the epidemiology of VAP is poorly documented in Asia. Methods: We systematically reviewed literature published on Ovid Medline, Embase Classic, and Embase from 1 January 1990 to 17 August 2017 to estimate incidence, prevalence, and etiology of VAP. We performed a meta-analysis to give pooled rates and rates by country income level. Results: Pooled incidence density of VAP was high in lower- and upper-middle-income countries and lower in high-income countries (18.5, 15.2, and 9.0 per 1000 ventilator-days, respectively). Acinetobacter baumannii (n = 3687 [26%]) and Pseudomonas aeruginosa (n = 3176 [22%]) were leading causes of VAP; Staphylococcus aureus caused 14% (n = 1999). Carbapenem resistance was common (57.1%). Conclusions: VAP remains a common cause of HAI, especially in low- and middle-income countries, and antibiotic resistance is high.

Plasma cell-free DNA: a potential biomarker for early prediction of severe dengue.

BACKGROUND: Considerable progress has been made in dengue management, however the lack of appropriate predictors of severity has led to huge number of unwanted admissions mostly decided on the grounds of warning signs. Apoptosis related mediators, among others, are known to correlate with severe dengue (SD) although no predictive validity is established. The objective of this study was to investigate the association of plasma cell-free DNA (cfDNA) with SD, and evaluate its prognostic value in SD prediction at acute phase. METHODS: This was a hospital-based prospective cohort study conducted in Vietnam. All the recruited patients were required to be admitted to the hospital and were strictly monitored for various laboratory and clinical parameters (including progression to SD) until discharged. Plasma samples collected during acute phase (6-48 h before defervescence) were used to estimate the level of cfDNA. RESULTS: Of the 61 dengue patients, SD patients (n = 8) developed shock syndrome in 4.8 days (95% CI 3.7-5.4) after the fever onset. Plasma cfDNA levels before the defervescence of SD patients were significantly higher than the non-SD group (p = 0.0493). From the receiver operating characteristic (ROC) curve analysis, a cut-off of > 36.9 ng/mL was able to predict SD with a good sensitivity (87.5%), specificity (54.7%), and area under the curve (AUC) (0.72, 95% CI 0.55-0.88; p = 0.0493). CONCLUSIONS: Taken together, these findings suggest that cfDNA could serve as a potential prognostic biomarker of SD. Studies with cfDNA kinetics and its combination with other biomarkers and clinical parameters would further improve the diagnostic ability for SD.

Association between dengue severity and plasma levels of dengue-specific IgE and chymase.

There is no definitive predictor of dengue severity, and this has led to a very large number of unnecessary hospitalizations worldwide. Although mast cell mediators are believed to a play role in dengue severity, the lack of precise kinetic data demands further research on early predictors. We enrolled 111 patients with confirmed dengue and 85 with "other febrile illness" (OFI) in a hospital-based prospective study in Vietnam. Dengue patients were classified as level 1, 2, or 3 based on the clinical intervention received. Blood samples were collected from each patient every day (pre- and post-defervescence) and after discharge. Plasma chymase, total IgE, and dengue-specific IgE were measured. Dengue-specific IgE levels showed an increasing trend during the course of illness and remained high even at post-discharge, although no significant difference was observed among severity levels. Total IgE showed no such trend. The specific IgE/total IgE ratio (S/T ratio) remained constantly higher in level 3 patients compared to other levels, with a significant difference at some time points. The S/T ratio of acute phase samples (before defervescence) tended to increase with increasing severity (level 1 < 2 < 3), and was significantly higher in level 3 patients than in level 1 and OFI patients. As an early predictor of severity allowing level 3 patients to be distinguished from other dengue patients, the S/T ratio achieved a sensitivity of 75% and specificity of 68%. We describe the kinetic profiles of IgEs, their ratio, and chymase levels at different severity levels. The S/T ratio was found to be associated with dengue severity, suggesting that it could potentially be used as an early predictor of severity.

Evolution and Spatiotemporal Dynamics of Enterovirus A71 Subgenogroups in Vietnam.

Background: Enterovirus A71 (EV-A71) is the major cause of severe hand, foot, and mouth disease and viral encephalitis in children across the Asia-Pacific region, including in Vietnam, which has experienced a high burden of disease in recent years. Multiple subgenogroups (C1, C4, C5, and B5) concurrently circulate in the region with a large variation in epidemic severity. The relative differences in their evolution and epidemiology were examined within Vietnam and globally. Methods: A total of 752 VP1 gene sequences were analyzed (413 generated in this study combined with 339 obtained from GenBank), collected from patients in 36 provinces in Vietnam during 2003-2013, along with epidemiological metadata. Globally representative VP1 gene datasets of subgenogroups were used to coestimate time-resolved phylogenies and relative genetic diversity to infer virus origins and regional transmission network. Results: Despite frequent virus migration between countries, the highest genetic diversity of individual subgenogroups was maintained independently for several years in specific Asian countries representing genogroup-specific sources of EV-A71 diversity. Conclusion: This study highlights a persistent transmission network of EV-A71, with specific Asian countries seeding other countries in the region and beyond, emphasizing the need for improved EV-A71 surveillance and detailed genetic and antigenic characterization.

A theoretical study on charge transport of dithiolene nickel complexes.

Organic semiconducting materials play an important role in the fabrication of high performance organic electronic devices. In the present work, we theoretically designed a series of organic semiconductors based on nickel complexes. Their characteristics of charge transport were investigated using DFT computational approaches. Based on the computed results, all compounds designed are found to be excellent candidates for ambipolar organic semiconductors with low reorganization energies for both holes and electrons. The (I-V) characteristics and transmission spectra of materials show that the replacement of benzene rings by thiophene rings results in an increase of their HOMO and LUMO energy levels. HOMOs of compounds containing thiophene end-groups are likely dominant for their conductance, while LUMOs of compounds containing benzene end-groups mainly affect their conductance. The electron distribution in these frontier MOs is identified as the main reason which makes the conductance of the compounds in the first series higher than those in the later series.

Raw pig blood consumption and potential risk for Streptococcus suis infection, Vietnam.

We assessed consumption of raw pig blood, which is a risk factor for Streptococcus suis infection in Vietnam, by using a mix-method design. Factors associated with consumption included rural residency, age, sex, occupation, income, and marital status. We identified risk groups and practices and perceptions that should be targeted by communication programs.

Epidemiology, clinical manifestations, and outcomes of Streptococcus suis infection in humans.

Streptococcus suis, a bacterium that affects pigs, is a neglected pathogen that causes systemic disease in humans. We conducted a systematic review and meta-analysis to summarize global estimates of the epidemiology, clinical characteristics, and outcomes of this zoonosis. We searched main literature databases for all studies through December 2012 using the search term "streptococcus suis." The prevalence of S. suis infection is highest in Asia; the primary risk factors are occupational exposure and eating of contaminated food. The pooled proportions of case-patients with pig-related occupations and history of eating high-risk food were 38.1% and 37.3%, respectively. The main clinical syndrome was meningitis (pooled rate 68.0%), followed by sepsis, arthritis, endocarditis, and endophthalmitis. The pooled case-fatality rate was 12.8%. Sequelae included hearing loss (39.1%) and vestibular dysfunction (22.7%). Our analysis identified gaps in the literature, particularly in assessing risk factors and sequelae of this infection.

Theoretical design of n-type organic semiconducting materials containing thiazole and oxazole frameworks.

The characteristics of molecular structure and charge transport of some new n-type organic semiconductors containing thiazole 1a-6a and oxazole 1b-6b frameworks and trifluoromethylphenyl as terminal groups were predicted using density functional theory (DFT) methods. The energy levels of HOMO and LUMO of these compounds are decreased when thiophene and furan units are replaced by thiazole and oxazole units, respectively. The same trend was observed when benzo[1,2-d:4,5-d']bisthiazole groups were replaced with benzo[1,2-d:4,5-d']bisthiazole-4,8-diones. The reorganization energies for electron of compounds are computed in a range of 0.21-0.37 eV, which is comparable to the value of 0.25 eV of well-known n-type semiconductors such as perfluoropentacene. Some important trends can be pointed out as follows: (i) replacing the core thiazolothiazole unit of compounds 1a and 2a by the larger core benzo[1,2-d:4,5-d']bisthiazole units of 3a and 4a decreases both reorganization energies for electron (λ(e)); (ii) the λ(e) values of compounds containing thiazole 2a, 4a, and 6a are smaller than those of compounds containing thiophene 1a, 3a, and 5a, respectively; (iii) there is no clear trend when replacing benzene rings of compounds 3a and 4a by quinone rings of 5a and 6a. The λ(e) values of 5 and 6 are only somewhat larger. The same trend is also found for compounds containing oxazole 1b-6b. The intermolecular charge transports in solid state of these compounds mainly occur among molecules in the same molecular layer, whereas intermolecular interactions between molecules in different molecular layers are very small. Generally, beside some experimentally reported molecules 1a-4a, the remaining molecules designed here are good candidates for n-type organic semiconducting materials with small reorganization energies for electron and low energy levels of LUMO.

A dataset on analysis of school-based management research from 1984 TO 2023.

The dataset aims to map scientific publications in the field of school-based management visually at the global level indexed by Scopus using Bibliometric analysis. It focuses on articles on School-Based Management at the international level. Research data were obtained from the Scopus database from 1984 to 2023 through the publish or perish software. Then the paper will be analyzed using the VOS viewer application for viewing and creating the desired Bibliometric maps. There is a sharp increase in the number of studies on this topic, especially from 2018 to 2022 and mainly from research in the US, Hong Kong, Australia, and developed countries. Moreover, the issues of most interest are SBM in terms of student achievement, schools, Hongkong, leadership, autonomy, school autonomy, governance, school effectiveness, school improvement, school reform, decentralization, education reform, education policy, decision-making, adolescent, article, human, humans, school health services, primary education. Policymakers and scholars can find great authors, research centers, influential studies and frequently published journals on this topic to read and research. Further studies based on the combination of bibliometric analysis with other methods may help paint a more profound picture of research findings on this topic.

Optimization of donor cell production for somatic cell nuclear transfer in the critically endangered Vietnamese I pig.

We aimed to establish efficient donor cells to produce piglets by somatic cell nuclear transfer (SCNT) of the endangered Vietnamese I pig. In Experiment 1, we assessed the effects of cell passages on the in vitro development of SCNT embryos. Cells with five and six passages showed significantly cleaved and blastocyst formation rates (86.72 and 86.64; 35.68 and 35.51, respectively, P < 0.05). The highest average total cell number per blastocyst was observed in groups of cells with five and six passages (50.45 and 50.18, respectively). Experiment 2 was performed to assess the sex of donor cells on the subsequent development of SCNT embryos. There was no significant difference in the cleaved and blastocyst formation rates, and the average total cell between female and male groups (86.51 % vs 86.94 % and 35.31 % vs 35.08 %, 50.29 % vs 50.67 %, respectively, P > 0.05). Experiment 3 was performed to assess the effect of cell lines on the development of SCNT embryos. Our results showed no significant difference in the success rate of fibroblast nuclear transfer into recipient oocytes, the cleaved and blastocyst formation rates, and the average total cell number per blastocyst among the cell lines 6004, 9154, 9155, 9156 and 9157 (P > 0.05). Experiment 4 was performed to assess the ability of SCNT embryos to induce pregnancy and to develop term. SCNT embryos were produced from I fibroblast cells established based on the results of Experiments 1, 2 and 3. Transfer of blastocyst stage embryos into 19 recipients (100-120 embryos in each) resulted in 14 pregnancies, in which 8 pregnant females terminated on Day 22-42 and 6 others produced 20 cloned piglets from donor cells of a female pig but 5 piglets died before birth and 15 healthy cloned piglets. However, 3 out of 15 healthy piglets died of unknown causes within 24h of birth and 3 out of 15 healthy piglets died at 3-5 days of age due to diarrhoea, 9 out of 15 healthy piglets are now 3 months of age. Finally, we established a protocol for the donor cell production which enabled the production of the endangered I pig embryos by SCNT and maximized blastocyst production rate by more than 35 % and pregnant rate after the transfer of cloned I pig embryos to recipients at 73.68 % for the first time in Vietnam.

Development of clinical decision rules to predict recurrent shock in dengue.

INTRODUCTION: Mortality from dengue infection is mostly due to shock. Among dengue patients with shock, approximately 30% have recurrent shock that requires a treatment change. Here, we report development of a clinical rule for use during a patient's first shock episode to predict a recurrent shock episode. METHODS: The study was conducted in Center for Preventive Medicine in Vinh Long province and the Children's Hospital No. 2 in Ho Chi Minh City, Vietnam. We included 444 dengue patients with shock, 126 of whom had recurrent shock (28%). Univariate and multivariate analyses and a preprocessing method were used to evaluate and select 14 clinical and laboratory signs recorded at shock onset. Five variables (admission day, purpura/ecchymosis, ascites/pleural effusion, blood platelet count and pulse pressure) were finally trained and validated by a 10-fold validation strategy with 10 times of repetition, using a logistic regression model. RESULTS: The results showed that shorter admission day (fewer days prior to admission), purpura/ecchymosis, ascites/pleural effusion, low platelet count and narrow pulse pressure were independently associated with recurrent shock. Our logistic prediction model was capable of predicting recurrent shock when compared to the null method (P < 0.05) and was not outperformed by other prediction models. Our final scoring rule provided relatively good accuracy (AUC, 0.73; sensitivity and specificity, 68%). Score points derived from the logistic prediction model revealed identical accuracy with AUCs at 0.73. Using a cutoff value greater than -154.5, our simple scoring rule showed a sensitivity of 68.3% and a specificity of 68.2%. CONCLUSIONS: Our simple clinical rule is not to replace clinical judgment, but to help clinicians predict recurrent shock during a patient's first dengue shock episode.

Polyaromatic hydrocarbon thin film layers on glass, dust, and polyurethane foam surfaces.

An investigation was conducted into the dynamic behavior of two polyaromatic hydrocarbon (PAH) semi-volatile organic compound (SVOC) naphthalene (NAP) and benzo [ghi]perylene (BghiP) in air and on various surfaces including glass, dust, and polyurethane foam (PUF) to understand their interaction with different media. A confocal fluorescence microscope and an infrared microscope were employed to detect and monitor the concentration-, time-, and temperature-dependent changes of the aromatic NAP and BghiP species on the surfaces. Infrared two-dimensional mapping of the vibrational characteristic peaks was used to track the two PAHs on the surfaces. Gas chromatography-mass spectrometry (GC-MS) was employed to measure the gaseous concentrations. The sorption of NAP and BghiP on the surfaces was estimated using Arizona desert sand fine (ISO 12103-1 A2) dust and organic contaminant household (SRM 2585) dust. The surface-to-air partition coefficients of NAP and BghiP were estimated on the different surfaces of glass, dust, and PUF. Molecular dynamic simulations were performed on dust surfaces based on the Hatcher model to understand the behavior of NAP and BghiP on dust surfaces. The Weschler-Nazaroff model was introduced to predictPAH film accumulation on the surfaces, providing a better understanding of PAH interaction with different environmental media. These findings could contribute to developing effective strategies to mitigate the adverse impact of PAHs on the environment and human health.

Spatial and phylogenetic patterns reveal hidden infection sources of Bacillus anthracis in an anthrax outbreak in Son La province, Vietnam.

Bacillus anthracis, the bacterial cause of anthrax, is a zoonosis affecting livestock and wildlife often spilling over into humans. In Vietnam, anthrax has been nationally reportable since 2015 with cases occurring annually, mostly in the northern provinces. In April 2022, an outbreak was reported in Son La province following the butchering of a water buffalo, Bubalus bubalis. A total of 137 humans from three villages were likely exposed to contaminated meat from the animal. Early epidemiological investigations suggested a single animal was involved in all exposures. Five B. anthracis isolates were recovered from human clinical cases along with one from the buffalo hide, another from associated maggots, and one from soil at the carcass site. The isolates were whole genome sequenced, allowing global, regional, and local molecular epidemiological analyses of the outbreak strains. All recovered B. anthracis belong to the A.Br.001/002 lineage based on canonical single nucleotide polymorphism analysis (canSNP). Although not previously identified in Vietnam, this lineage has been identified in the nearby countries of China, India, Indonesia, Thailand, as well as Australia. A twenty-five marker multi-locus variable number tandem repeat analysis (MLVA-25) was used to investigate the relationship between human, soil, and buffalo strains. Locally, four MLVA-25 genotypes were identified from the eight isolates. This level of genetic diversity is unusual for the limited geography and timing of cases and differs from past literature using MLVA-25. The coupled spatial and phylogenetic data suggest this outbreak originated from multiple, likely undetected, animal sources. These findings were further supported by local news reports that identified at least two additional buffalo deaths beyond the initial animal sampled in response to the human cases. Future outbreak response should include intensive surveillance for additional animal cases and additional molecular epidemiological traceback to identify pathogen sources.

Review of antibiotic prescriptions as part of antimicrobial stewardship programmes: results from a pilot implementation at two provincial-level hospitals in Viet Nam.

Objectives: To investigate the feasibility of retrospective prescription-based review and to describe the antibiotic prescribing patterns to provide information for an antimicrobial stewardship programme in Viet Nam. Methods: This study was conducted in two provincial-level hospitals between February and April 2020. Reviews were done by a clinical team consisting of leaders/senior doctors of each ward to assess the optimal level (optimal/adequate/suboptimal/inadequate/not assessable) of antibiotic prescriptions. Mixed-effect logistic regression at prescription level was used to explore factors associated with optimal antibiotic use. Results: The retrospective prescription-based review was accepted by study clinical wards with varied levels of participants. One hundred and eighty-three patients (326 prescriptions) in Hospital 1 and 200 patients (344 prescriptions) in Hospital 2 were included. One hundred and nineteen of the 326 (36.5%) antibiotic prescriptions in Hospital 1 and 51/344 (14.8%) antibiotic prescriptions in Hospital 2 were determined to be optimal by the review teams. The number of adequate antibiotic prescriptions were 179/326 (54.9%) and 178 (51.7%) in Hospital 1 and Hospital 2, respectively. The optimal level was lower for surgical prophylaxis antibiotics than for empirical therapy (OR = 0.06; 95% CI 0.01-0.45), higher in prescriptions in the ICU (OR = 12.00; 95% CI 3.52-40.92), higher in definitive antibiotic therapy (OR = 48.12; 95% CI 7.17-322.57) and higher in those with an indication recorded in medical records (OR = 3.46; 95% CI 1.13-10.62). Conclusions: This study provides evidence on the feasibility of retrospective prescription-based review, with adaption to the local situation. High and varying levels of optimal antibiotic prescriptions in clinical wards in hospitals were observed in Viet Nam.

The π-conjugated P-flowers C16(PH)8 and C16(PF)8 are potential materials for organic n-type semiconductors.

Following the theme of this special issue, two new compounds, the P-flowers C(16)(PH)(8) and C(16)(PF)(8), are designed by us and subsequently characterized by quantum chemical computations. Their geometries and infrared signatures are analyzed and compared to those of the well-known sulflower C(16)S(8). Their electronic structure and aromaticity are examined using the electron localization function (ELF) and also by the total and partial densities of state (DOS). Both C(16)(PF)(6) and C(16)(PH)(8) molecules exhibit small energy barrier of electron injection (Φ(e) = 0.33 eV for the gold electrode for the former, and Φ(e) = 0.1 eV for the calcium electrode for the latter), remarkably low reorganization energy and high rate of electron hopping. Thus, both theoretically designed P-flower molecules are predicted to be excellent candidates for organic n-type semiconductors.