Model of implementing proficiency testing in Vietnam, a developing country.

Backgrounds and aims: The aim of this study is to provide a good approach for a quantitative EQA scheme assigned value with limited resources. Materials and methods: Twelve lyophilized EQA items were distributed to participants in 2021 from North to Southeast Vietnam to measure the concentration of nine parameters, including glucose, urea, creatinine, cholesterol, triglyceride, uric acid, AST, ALT, and GGT. The consensus value of the expert group and all participants were calculated and statistically compared to choose the most appropriate consensus value. Results: Fifty-nine laboratories attended the EQA scheme, including an expert group using automatic biochemistry analyzers (AAs) and all participants with auto and semi-auto biochemistry (SAA) analyzers. Consensus values of six per nine parameters were different between the two groups for at least two EQA items, including glucose, creatinine, cholesterol, uric acid, AST, and ALT. The coefficients of variation of glucose, urea, creatinine, triglycerides, uric acid, and GGT in the expert group were significantly lower than those in all the participants. Conclusion: Using the consensus values of expert groups as the assigned values of the EQA program is a relevant strategy to increase testing quality in developing countries with limited resources, such as Vietnam.

Ultra-thin light-weight laser-induced-graphene (LIG) diffractive optics.

The realization of hybrid optics could be one of the best ways to fulfill the technological requirements of compact, light-weight, and multi-functional optical systems for modern industries. Planar diffractive lens (PDL) such as diffractive lenses, photonsieves, and metasurfaces can be patterned on ultra-thin flexible and stretchable substrates and be conformally attached on top of arbitrarily shaped surfaces. In this review, we introduce recent research works addressed to the design and manufacturing of ultra-thin graphene optics, which will open new markets in compact and light-weight optics for next-generation endoscopic brain imaging, space internet, real-time surface profilometry, and multi-functional mobile phones. To provide higher design flexibility, lower process complexity, and chemical-free process with reasonable investment cost, direct laser writing (DLW) of laser-induced-graphene (LIG) is actively being applied to the patterning of PDL. For realizing the best optical performances in DLW, photon-material interactions have been studied in detail with respect to different laser parameters; the resulting optical characteristics have been evaluated in terms of amplitude and phase. A series of exemplary laser-written 1D and 2D PDL structures have been actively demonstrated with different base materials, and then, the cases are being expanded to plasmonic and holographic structures. The combination of these ultra-thin and light-weight PDL with conventional bulk refractive or reflective optical elements could bring together the advantages of each optical element. By integrating these suggestions, we suggest a way to realize the hybrid PDL to be used in the future micro-electronics surface inspection, biomedical, outer space, and extended reality (XR) industries.

Development of a robust blood smear preparation procedure for external quality assessment.

INTRODUCTION: The external quality assessment (EQA) scheme is particularly important for laboratory performance evaluation. Peripheral blood smears are necessary to identify morphological features, and the procedure for preparing such smears must be robust to meet the ISO 15189 standard. Although blood smear preparation is a routine activity in medical laboratories, an appropriate procedure for preparing a series of blood smears with high homogeneity and durable stability for EQA purposes has not yet been published elsewhere. For this reason, a robust procedure was developed and validated in this study. METHODS: Various factors affecting blood smear preparation, such as the amount of time collected blood samples are stored before fixation, suitable reagents, and specification parameters for each step, including fixation, staining, and timing of the staining steps, were studied. Each experiment was evaluated based on homogeneity and stability characteristics. RESULTS: Whole blood mixed with EDTA anticoagulant was used to make the blood smears. Samples were fixed with pure anhydrous alcohol and stained in Coplin jars using the Wright-Giemsa method. CONCLUSION: The homogeneity and stability of two lots of smears suitable for EQA purposes was confirmed based on intact morphology of the smears for more than 8 months at room temperature.

Establishment of an Experimental Procedure for Preparing Trial Serum Samples for the Specific Serodiagnosis of Toxocara canis for External Quality Assessment Schemes.

BACKGROUND: External quality assessment (EQA) provides evidence of reliable, accurate, and precise results for customers using the diagnostic test for Toxocara canis. Objective. To establish a procedure for producing standard Toxocara canis serum samples for serodiagnostic testing in EQA. METHODS: The collected serum samples to contain anti-Toxocara canis serum samples for serodiagnostic testing in EQA. F-test and a T-test were applied to evaluate their homogeneity and stability. RESULTS: Among eleven samples positive by ELISA, ten of them were confirmed via Western blotting by positive reaction with 5 specific Toxocara canis serum samples for serodiagnostic testing in EQA. Toxocara canis serum samples for serodiagnostic testing in EQA. p > 0.05). Samples produced by both methods were stable for 7 days at 30°C (p > 0.05). Samples produced by both methods were stable for 7 days at 30°C (. CONCLUSION: Specific serodiagnosis samples of anti-Toxocara canis antibodies for EQA could be produced that possessed homogeneity and stability lasting for 3 months and 6 months by the freeze-drying and freezing methods, respectively. At 30°C, the samples produced by both methods were stable for 7 days, suitable for delivery to remote laboratories.Toxocara canis serum samples for serodiagnostic testing in EQA.

Finding optimal surface sites on heterogeneous catalysts by counting nearest neighbors.

A good heterogeneous catalyst for a given chemical reaction very often has only one specific type of surface site that is catalytically active. Widespread methodologies such as Sabatier-type activity plots determine optimal adsorption energies to maximize catalytic activity, but these are difficult to use as guidelines to devise new catalysts. We introduce "coordination-activity plots" that predict the geometric structure of optimal active sites. The method is illustrated on the oxygen reduction reaction catalyzed by platinum. Sites with the same number of first-nearest neighbors as (111) terraces but with an increased number of second-nearest neighbors are predicted to have superior catalytic activity. We used this rationale to create highly active sites on platinum (111), without alloying and using three different affordable experimental methods.

Clinical description of a completed outbreak of SARS in Vietnam, February-May 2003.

We investigated the clinical manifestations and course of all probable severe acute respiratory syndrome (SARS) patients in the Vietnam outbreak. Probable SARS cases were defined by using the revised World Health Organization criteria. We systematically reviewed medical records and undertook descriptive statistical analyses. All 62 patients were hospitalized. On admission, the most prominent symptoms were malaise (82.3%) and fever (79.0%). Cough, chest pain, and shortness of breath were present in approximately one quarter of the patients; 79.0% had lymphopenia; 40.3% had thrombocytopenia; 19.4% had leukopenia; and 75.8% showed changes on chest radiograph. Fever developed on the first day of illness onset, and both respiratory symptoms and radiographic changes occurred on day 4. On average, maximal radiographic changes were observed on day 10, and fevers subsided by day 13. Symptoms on admission were nonspecific, although fever, malaise, and lymphopenia were common. The complications of SARS included invasive intubation and ventilation (11.3%) and death (9.7%).