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This study uses remote sensing images combined with Geographic Information Systems statistical approach - spatial autocorrelation analysis to identify traffic incident hotspot locations. It evaluates the statistical significance of hotspot clusters to support forecasting road traffic incidents applied for Thanh Hoa province of Vietnam with traffic accident data during four years from 2020 to 2023. Based on spatial analysis techniques, including severity index and Getis-Ord Gi* statistical analysis with inverse distance weighting interpolation, hotspot clusters are identified and sorted by rank. Applying spatial autocorrelation analysis has important implications in enumerating hotspots in sequence. The analysis results identified 64 hotspots, of which the 32 dangerous incident points are in Thanh Hoa province's transportation system. The results demonstrate the effectiveness of using Getis-Ord Gi* spatial statistical techniques to identify traffic incident hotspot locations and evaluate the statistical significance of hotspot clusters to support forecasting road traffic incidents in Thanh Hoa province. [ABSTRACT FROM AUTHOR]

In this study, Fe3O4 nanoparticle-loaded biochar derived from the pomelo peel (FO-PPB) was synthesized and applied as an affordable material for the adsorption of Reactive Red 21 (RR21) in an aqueous solution. The characteristics of FO-PPB were evaluated by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), X-ray diffraction (XRD), Raman spectra, Fourier transform infrared spectra (FTIR), and Brunauer–Emmett–Teller (BET) surface area. The adsorption process of FO-PPB with RR21 was evaluated through batch experiments to examine various parameters including solution pH, contact time, adsorbent dose, initial RR21 concentration, and solution temperature. Results show that FO-PPB produced by the impregnation ratio between iron (Fe) and pomelo peel biochar (PPB) of 5 : 1 (w/w) had the best adsorption performance. The adsorption capacities of PPB and FO-PPB at optimum experimental conditions (solution pH 3, contact time of 60 min, solution temperature of 40°C, initial RR21 concentration of 300 mg/L, and adsorbent dose of 2 g/L) were 18.59 and 26.25 mg/g, respectively. The adsorption isotherms of RR21 on PPB and FO5-PPB were described well by Langmuir and Sips models with high R2 values of 0.9826 and 0.9854 for FO5-PPB and 0.9701 and 0.9903 for PPB, respectively. The obtained data also well matched the pseudo-first-order and pseudo-second-order models with R2 values ≥ 0.96. Chemisorption through sharing or electronic exchange was determined as the main adsorption mechanism. [ABSTRACT FROM AUTHOR]

The sonochemical synthesis of a chitosan-ZnO/Fe 3 O 4 nanocomposite yielded a highly porous structure and large surface area for enhancing the photocatalytic degradation of cationic (rhodamine B, RhB) and anionic (methyl orange, MO) dyes in aqueous solution. Chitosan-ZnO/Fe 3 O 4 demonstrated a significant enhancement in photodegradation efficiency 99.49% for MO ( C = 5.32 mg L 0 = 5.32 mg L -1 , t = 5.03 mg L C 0 = 5.03 mg L -1 , t = 150 min) under visible light due to its narrow bandgap of 2.84 eV. The photocatalytic performance was investigated by varying the pH, dye concentration, reaction time, and catalyst dose. The photocatalytic reaction obeyed the Langmuir-Hinshelwood kinetic model owing to a high rate constant of 0.031 (min -1 ) and 0.013 (min -1 ) for the degradation of MO and RhB, respectively. The photocatalytic activity of the chitosan-ZnO/Fe 3 O 4 nanocomposite lost 18.37% (MO degradation) and 11.08% (RhB degradation) of its performance after the first four cycles. The presented results highlight the degradation efficiency of the chitosan-ZnO/Fe 3 O 4 nanocomposite under visible light irradiation with reusable and magnetically retrievable abilities., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

The roles of Mn 2+ ions in the MnCO 3 compound, leading to the formation of an Mn 2+ -Yb 3+ dimer and affecting the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions and near-infrared (NIR) emission bandwidth flatness of Er 3+ /Tm 3+ /Yb 3+ co-doped in SiO 2 -ZnO-BaO (SZB) barium zinc silicate glasses, were investigated in this work. The composition of all elements from the original raw materials that exist in the host glasses was determined using energy-dispersive X-ray spectroscopy (EDS). Under the excitation of a 980 nm laser diode (LD), the NIR emission of Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses produced a bandwidth of about 430 nm covering the O, E, and C bands. The effects of Mn 2+ ions and the Mn 2+ -Yb 3+ dimer on the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions and bandwidth flatness of NIR emission of Er 3+ /Tm 3+ -co-doped and Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses were also assigned. The optimal molar concentration of Mn 2+ ions was determined such that the NIR bandwidth flatness of Er 3+ /Tm 3+ /Yb 3+ -co-doped SZB glasses was the flattest. In addition, the role of Mn 2+ ions in reducing the gain coefficient for the 4 I 13/2 → 4 I 15/2 transition of Er 3+ ions was also calculated and discussed., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

In this study, the indirect/direct optical band gaps and spectroscopy properties of Bi m + /Eu n + /Yb 3+ co-doped ( m = 0, 2, 3; and n = 2, 3) zinc calcium silicate glasses under different excitation wavelengths were investigated. Zinc calcium silicate glasses with the main compositions of SiO 2 -ZnO-CaF 2 -LaF 3 -TiO 2 were prepared by the conventional melting method. EDS analysis was performed to determine the elemental composition existing in the zinc calcium silicate glasses. Visible (VIS)-, upconversion (UC)-, and near-infrared (NIR)-emission spectra of Bi m + /Eu n + /Yb 3+ co-doped glasses were also investigated. Indirect optical band gaps and direct optical band gaps of Bi m + -, Eu n + - single-doped, and Bi m + -Eu n + co-doped SiO 2 -ZnO-CaF 2 -LaF 3 -TiO 2 -Bi 2 O 3 -EuF 3 -YbF 3 zinc calcium silicate glasses were calculated and analyzed. CIE 1931( x , y ) color coordinates for VIS and UC emission spectra of Bi m + /Eu n + /Yb 3+ co-doped glasses were determined. Besides, the mechanism of VIS-, UC-, NIR-emissions, and energy transfer (ET) processes between Bi m + and Eu n + ions were also proposed and discussed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The health care system in Vietnam has long been cited as an example of primary health care that has worked well. The achievements of the system during the past decades have indeed been impressive, but the changing economic situation in Vietnam has consequences for all public sector activities, including health care. Liberalization of economic policies has encouraged private medical practice and free trade in medicines and drugs, while financial support for the state health system is decreasing. Equity has always been an important goal for the vietnamese health system, but it becomes harder and harder to realize under the new conditions of financing. The restrictions in centralized planning and funding brought about by recent changes also reveal weak points in the system, from planning to training to management at the different levels. This situation is discussed and issues concerning policy, legislation and human resources are highlighted in terms of their effect on equity.

Calcium activated proteolysis of brain spectrin produces characteristic breakdown products (BDPs), the concentrations of which increase markedly in many instances of brain pathology. Results reported here indicate that levels of the BDPs rise with age (3-30 months) in the telencephalon but not in the hindbrain of Balb/c mice. These observations suggest that spectrin breakdown is a pathologic biochemical marker which increases with age in some but not all brain regions.

Pharmacokinetics of theophylline elimination were studied in a 54-child population. Subjects' ages ranged from three months to six years. The mean half life was 4.92 hours, with S.D. +/- 1.88 hours. This is at variance with previous reports. Ages and half lives were compared and there were no correlations in this young age group.