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Microwave hybrid heating (MHH) process is a unique and novel approach of joint materials. Several lightweight materials (medium and high melting point) such as nickel, copper and aluminum have been successfully joined in the past research. However, small dimensions and low melting point of light weight materials such as zinc (Zn) metal or zinc (Zn) powder were always being a challenging mere for creating bond via any joining techniques. The sheets of stainless steel SS304 (17 mm×7.9 mm×0.2 mm) have been fabricated and joined at lap joint by using novel Microwave hybrid heating technique with mini heat chamber of 2.45 GHz of frequency and 200 W–360 W of microwave power, using pure zinc powder (99.9 %) as an interface material. Epoxy rate and exposure time have been varied from 10 % to 20 % and 2 min to 4 min, respectively. A developed heat chamber has been set in domestic microwave oven properly as proposed. To evaluate the microstructure correlation and microhardness at joint interface, the field emission scanning electron microscopy (FESEM – EDS), x‐ray diffraction (XRD) and Vickers hardness were used. For the experimental studies, it had found an excellent bonding was produced at interface layer between the upper and lower sections with good penetration rate of 360 W of microwave power, 4 min of exposure time and 20 % of epoxy rate as the 183.1 HV 0.05 of excellent microhardness and the intermetallic phase of iron‐zinc (FeZn11), nickel‐zinc (NiZn) and nickel‐zinc (NiZn3) were observed at interface layer. [ABSTRACT FROM AUTHOR]

Metal bonding via joints of low melting point materials such as zinc and tin has been technically challenging. This paper presents a unique technique for bonding small dimensions and the low melting point of materials through the microwave hybrid heating (MHH) process. Joint of stainless steel SS304 was applied to the joint with the tin (Sn) powder with the application of microwave radiation by using domestic microwave oven at 2.45 GHz of constant frequency, 200–360 W of microwave power, 120–180 s of exposure time, and 10–20 % of the epoxy rate. A developed heat chamber was used as a susceptor and insulator in the microwave hybrid heating (MHH) process. The tin powder and parent metals were strongly bonded as lap position by the microwave hybrid heating (MHH) process at 360 W of microwave power, 180 s of constant exposure time, and 20 % of the constant epoxy rate. Characterization of the joint was evaluated through microhardness and x‐ray diffraction (XRD) analysis techniques. It was found that the intermetallic compounds (phase) of nickel tin (NiSn), iron tin (Fe1.84Sn), sulfur tin (SSn), chromium tin (Cr2Sn3), chromium tin (CrSn2), and tin phosphorus (SnP) at the joint surface with highest microhardness obtained at 498.4 HV 0.05 at 360 W of microwave power. [ABSTRACT FROM AUTHOR]

Background The standard treatment for localized osteosarcoma is neoadjuvant chemotherapy before surgery, followed by adjuvant chemotherapy. Our aim was to report the rate of histopathological response to neoadjuvant chemotherapy for the treatment of extremity osteosarcoma in Vietnam. Methods We performed a retrospective study of stage II conventional osteosarcoma patients under 40 years-old who received MAP regimen as neoadjuvant chemotherapy at the Vietnam National Cancer Hospital between June 2019 and June 2022. Histopathological response was evaluated using the Huvos grading system, in which a good histopathological response was defined as a necrotic rate of 90% or more. Results Thirty-five eligible patients were included in the study. Male patients accounted for 65.7%, with a median age of 16 years (range, 8-38 years). Of the 35 cases, 31 were reported as stage IIB (88.6%). The femur and tibia were the most common sites in our study, accounting for 51.4% and 34.3%, respectively. The most common pathologic subtype was osteoblastic osteosarcoma (68.6%), followed by chondroblastic subtype (20%). After two cycles of MAP-regimen neoadjuvant chemotherapy, 28 of 35 patients (80%) underwent limb-sparing surgery. A good histopathological response was observed in 18 of 35 patients (51.4%). There were significant correlations between the duration of symptoms ( P = 0.016), LDH ( P = 0.001) serum levels at initial presentation, and ALP ( P = 0.043) serum levels at initial presentation with histopathological response. Conclusion This retrospective study suggests a possible association between symptom duration, pre-treatment LDH levels, and pre-treatment ALP levels with histopathological response rates. Additional clinical investigations with long-term follow-up are needed to investigate survival outcomes in the Asian population.

Nutritional, physicochemical, functional, antioxidative and digestion properties of brown and white rice flours from four Thai rice varieties (Luangpatue, upland rice, RD43, and Hommali) were investigated and compared. Due to differences in grain color, the color parameters of flours varied significantly. Protein, fat, ash, carbohydrate, and moisture content, total dietary fiber, and calories of these rice flours were 6.94–10.21%, 1.68–3.16%. 0.554–1.442%, 71.20–79.68%, 9.79–10.53%, 1.07–3.64%, and 350.82–362.73 kcal/100g, respectively. RD43 brown rice (18.4%) and Luangpatue white rice (26.5%) respectively exhibited the lowest and highest amylose content. Luangpatue rice flours also showed higher swelling power, setback value, final viscosity, and thermal properties than other varieties. The variations in hydration properties and oil absorption index were noticeable among these rice flours. In addition, the highest level of total phenolic content and antioxidant activity led to the lowest estimated glycemic index (eGI = 62.92) found in upland brown rice. It was confirmed by the multivariate analysis results. This study reported the diverse physicochemical properties and composition-property relationships of two kinds of flours from four rice varieties collected from Thailand for the first time. It exhibited possible capabilities for the development of various rice-based products that promote health based on their characteristics on industrial scale.

This study proposes the model for interpolating time series to use them to forecast effectively for future. This model is established based on the improved fuzzy clustering analysis problem, which is implemented by the Matlab procedure. The proposed model is illustrated by a data set and tested for many other datasets, especially for 3003 series in M3- Competition data. Comparing to the existing models, the proposed model always gives the best result. We also apply the proposed model in forecasting the salt peak for a coastal province of Vietnam. Examples and applications show the potential of the studied problem. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the ability to improve the capacity of cold swelling and cold-water solubility of rice starch by ultrasonic-assisted alcohol-alkaline and alcohol-alkaline methods. To achieve this, ultrasound powers (U) were varied (30%, 70%, 100%) under the granular cold-water swelling starch (GCWSS) preparation (GCWSS + 30 %U, GCWSS + 70 %U, and GCWSS + 100 %U). The effects of these methods on morphological, pasting properties, amylose content, ratio of 1047/1022 spectra by FTIR, turbidity, freeze–thaw stability, and gel texture were also studied and compared. The results showed that the surface of GCWSS granules presented a honeycomb especially GCWSS + U treatments exhibited more porous on the surface of starch granules. The cold swelling power and solubility of GCWSS + U samples were increased which confirmed by reducing ratio of ordered structure to amorphous structure of starch, and turbidity was also decreased. Moreover, pasting temperature, breakdown, final viscosity, and setback decreased while peak viscosity increased as measured using a Rapid Visco Analyzer. The freeze–thaw stability of GCWSS + U was more resistant to syneresis than GCWSS under repeated freeze–thaw cycles. The reduction of gel hardness and springiness was observed using Texture Analyzer. These changes were enhanced with increasing ultrasound powers. Thus, the results indicate that the different ultrasound-assisted alcohol-alkaline treatments for preparing GCWSS show an effective use in the preparation of GCWSS with improved cold-water swelling and reduced retrogradation of rice starch.

Abstract T263P mutation is one of the rare EGFR mutations located on chromosome 7p11.2, which is a change in amino acid residue at position 263 of the epidermal growth factor receptor protein, where L‐threonine has been replaced by L‐proline. This missense mutation in the extracellular EGFR domain is not well‐known in lung cancer. In this study, we first report a patient with advanced lung adenocarcinoma harbouring only a rare T263P EGFR mutation who benefited from first‐line afatinib therapy in Vietnam. The patient achieved a partial response with a time‐to‐treatment failure of 5 months. The patient subsequently received several chemotherapy regimens as the disease progressed, with overall survival of 17 months. Non‐small cell lung cancer with a rare T263P EGFR mutation responds to afatinib but has a poor prognosis. Further studies are needed to determine the efficacy of targeted therapies in this specific population.

Abstract BRAF mutations are uncommon in non‐small cell lung cancer (NSCLC), accounting for less than 5% of all NSCLC cases. The utilization of targeted therapies in non‐V600E BRAF mutant NSCLC is considered controversial, although non‐V600E genotype is reported in ~50% of all BRAF mutant patients. We document the case of a 63‐year‐old patient with NSCLC harbouring a rare BRAF E501Q mutation, who had prolonged response to immunotherapy combined with chemotherapy in Vietnam. The patient was diagnosed with metastatic PD‐L1‐negative lung adenocarcinoma and received pembrolizumab plus chemotherapy as first‐line treatment. After completing 35 cycles of pembrolizumab and pemetrexed, his disease has remained stable during the treatment‐free follow‐up period, and he is alive 38 months after treatment initiation at the latest follow‐up. Immune‐based therapy is an appropriate option for lung adenocarcinoma with rare non‐V600E BRAF mutation. Further clinical studies are necessary to determine the effectiveness of using immune‐based therapy in this specific population.

The objective of this study was to analyze the effects of different single or dual physical treatments, including pre-gelatinization (PBF), annealing (ANN), PBF+ANN, and ANN+PBF, on banana flour’s characteristics and its application in gluten-free chip production. The study involved determining the color, swelling capacity, solubility, oil absorption index, and pasting properties of both the native and modified banana flour samples. The results showed a significant change in color, particularly in the pre-gelatinized samples. There was a noticeable decrease in the values of the pasting parameters in the modified samples. PBF samples exhibited a remarkable reduction in the breakdown value compared to the native and ANN treated samples. Furthermore, PBF-treated banana flour displayed higher oil absorption and swelling power than the other samples, along with lower solubility in the PBF-treated sample. These characteristics appear to be responsible for enabling the pre-gelatinized sample to form the dough required for producing banana chips, resulting in distinct texture profiles. Finally, our research emphasizes the useful application of modified banana flour in the food industry and emphasizes how crucial it is to choose the right modification method to achieve the desired effects on the product.

Abstract Background Most recent laboratory studies have suggested a promising role of vitamin D and its analogs as novel chemotherapeutic agents for cancer treatment. However, epidemiological evidence, especially regarding the effects of vitamin D on gastric cancer is still inconsistent. Objectives Our research aimed to evaluate the associations between vitamin D intake and the risk of developing gastric cancer through a case-control study in North Vietnam. Methods We accessed databases of the previous completed case-control studies to derive 1182 incident gastric cancer cases and 2995 hospital controls selected from hospitals in Hanoi from 2003 to 2019. Vitamin D intake was computed by multiplying the food frequency intake with nutrient content based on the Viet Nam Food Composition Tables. Data were collected through face-to-face interviews by trained interviewers using the validated semi-quantitative food frequency and demographic lifestyle questionnaires. The odds ratio and 95% confidence interval (OR and 95%CI) were estimated using unconditional logistic regression analysis. Results We observed a continual decline in gastric cancer risk according to the level-up of vitamin D intake in both genders, men, and women [Fifth vs. bottom quintile, OR, 95%CI: 0.68 (0.53, 0.86), OR, 95%CI: 0.72 (0.53, 0.97), OR, 95%CI: 0.58 (0.38, 0.89), respectively. Per increment quintile, the statistically significant decreased risk was seen by 7% in men and 13% in women. The significant inverse association between vitamin D intake remained in the subgroups of ever and never tobacco smoking; negative and positive H. pylori infection. Conclusion The findings suggested that sufficient vitamin D intake was associated with a lower risk of Gastric Cancer in the Vietnamese population.

Objectives This study aims to investigate the anti-hypertensive effects of aqueous extract of Callisia fragrans and their underlying mechanism using a two-kidney one-clip (2K1C) model of reno-vascular hypertension in rats. Methods The reno-vascular hypertensive rats were treated with C. fragrans leaf extract (100 and 500 mg/kg; p.o.) and a reference drug, captopril (20 mg/kg; p.o.), for 4 weeks. The blood pressure and heart rate were recorded using a tail-cuff. The heart weight, left ventricular wall thickness, and serum creatinine and urea levels were measured. A spectrophotometric assay was used to analyze the angiotensin-converting enzyme (ACE) inhibition activity of the extract and the reference drug. The total volume and the concentration of sodium, potassium, and chloride in urine samples were evaluated. Results C. fragrans extract significantly reduced both systolic and diastolic blood pressures in the reno-vascular hypertensive rats. No significant difference in the heart rate was observed between each animal group. C. fragrans extract reduced the 2K1C-induced increase in the heart and body weight ratio and the left ventricular wall thickness. Moreover, the extract also attenuated the increase in serum urea induced by the 2K1C treatment. C. fragrans extract inhibited ACE activity in vitro with an IC50 of 20.97 ± 3.94 µg/ml. The urine output and urinary electrolyte excretion significantly increased in C. fragrans extract-treated rats. Conclusions These findings demonstrated that C. fragrans extract can mitigate hypertension and alleviate ventricular hypertrophy and renal dysfunction in reno-vascular hypertensive rats, at least in part via ACE activity inhibition and diuretic property.

Abstract A complex of G719X and S768I mutations is infrequently observed, constituting less than 0.3% of all EGFR‐positive non‐small cell lung cancer (NSCLC), and the response to first‐line TKIs is inconsistent in the literature. In this study, we report a patient with metastatic non‐small cell lung cancer carrying rare EGFR compound mutations of G719X and S768I who benefited from first‐line treatment with gefitinib in Vietnam. This patient had a prolonged response lasting over 44 months with first‐generation TKI. He continued to take gefitinib without experiencing serious adverse events. NSCLC with a rare complex of G719X and S768I mutation revealed a good response to gefitinib.

Rice is a staple food and energy source for half the world’s population. Due to its quick digestion and absorption in the gastrointestinal tract, rice is typically regarded as having a high or medium–high glycemic index (GI); however, this can vary depending on the variety, nutrient compositions, processing, and accompanying factors. This report included a table of the glycemic index for rice and rice products in different countries, which could give an overview and fundamental information on the recent GI of different rice varieties. In addition, latest updates about the mechanism effects of rice nutritional profiles and processing techniques on GI were also provided and discussed. The influence of state-of-the-art GI regulation methods was also evaluated. Furthermore, the effectiveness and efficiency of applied technologies were also given. Furthermore, this review offered some aspects about the potential nutraceutical application of rice that food scientists, producers, or consumers might consider. Diverse types of rice are grown under various conditions that could affect the GI of the product. The instinct nutrients in rice could show different effects on the digestion rate of its product. It also revealed that the rice product’s digestibility is process-dependent. The postprandial glucose response of the rice products could be changed by modifying processing techniques, which might produce the new less-digestive compound or the inhibition factor in the starch hydrolysis process. Because of the significant importance of rice, this paper also concluded the challenges, as well as some important aspects for future research.

White rice samples, Chai-Nat1 (CN1) and Jasmin rice (KDML105), were treated with the ultrasound-chilling (UC) and combined with annealing treatments (UC + ANN 45, UC + ANN50, and UC + ANN55). Their physicochemical properties and in vitro glycemic index of rice samples were analyzed. UC + ANN treatments presented pasting temperature, gelatinization temperature and crystallinity increased whereas the glycemic index of both rice samples was decreased as compared to its native. Especially, UC + ANN55 treated rice produced the lowest glycemic index and starch hydrolysis. Moreover, UC + ANN treated CN1 rice exhibited delayed gelatinization temperature, increased gelatinization enthalpy, and decreased glycemic index than KDML105 rice. In addition, Pearson’s correlation presented that UC + ANN and amylose content had a highly negative correlation with the glycemic index at p

Objectives: The aim was to describe the characteristics and outcomes of treatments for coronavirus infection in cancer survivors in Viet Nam from 23 January to 6 May 2020. Methods: We accessed data registration and publication of cases tested positive with COVID-19 by the Ministry of Health in Viet Nam. Characteristics of reported positive cases included age, sex, sources of infection, nationality, the onset of symptoms, and history of chronic diseases. The outcomes included incubation, suspected, clinical course, and clearance time by the subgroup of patients having a history of cancer and non-cancer. T-test was used to compare two means of these groups. Results: Three men patients were cancer survivors (1.1% of 271 cases),a Chinese business aged 66 having lung cancer (ICD-10: C34), a Sweden tourism aged 64 having blood cancer (ICD-10: C81-C96), and a Vietnamese aged 71 having liver cancer (ICD-10: C22). The remaining 268 patients were free-cancer. The clinical course of three cancer survivors was 17.3 days that were shorter 3.2 days when compared to non-cancer, p=0.2068. The estimated suspected time was longer in cancer survivors (5.3 days) than non-cancer (1.5 days), p =0.0394. The mean age was older in cancer survivors (67-year-old) than non-cancer (35.5-year-old), p =0.0003. Conclusions: Cancer survivors might be at high risk of COVID-19 infection due to their underlying vulnerable health condition related to cancer disease and they need extra care to minimize the risk of infection from coronavirus.

Aims: This study aimed to describe the characteristics of the workplace-related clusters of COVID-19 and its transmissions into communities in Vietnam. Methods and Material: We accessed the database of COVID-19 by the Ministry of Health, Vietnam. Variables included sources of infection, age, sex, nationality, the dates of onset of symptoms and discharge from hospitals, and ID of each patient tested positive with COVID-19. Information from each patient was linked to the sources of infection to identify workplace-related clusters. Among 314 patients, we excluded 43 cases related to two charter flights, the remaining 271 cases were eligible for the study. Results: The biggest cluster of hospital canteen included 26 workers and their 31 family members or hospital’s patients. The second biggest cluster included a pilot of the Vietnam airlines and other 16 patients who have close contact with him at the Bar Buddha at Ho Chi Minh City. A total of 87 patients (32.1% of 271 cases) were related to these workplace-related clusters. The suspected time and the clinical course was significantly longer in the workplace-related clusters than other patients (mean 6.52 vs. 4.05 days, p=0.0191) and (mean 28.71 vs. 20.52 days, p=0.0005), respectively. Conclusions: Because COVID-19 infection at workplaces was responsible for nearly one-third of the total patients, there was a novel emerged occupational risk factor at work due to coronavirus infection. Safety at the workplace in preventing COVID-19 transmission is highly needed.

Geosmin is a naturally occurring compound released when soil-present microbes die. Communities can periodically experience episodes of unpleasant-tasting water when a sharp drop in this microbe population releases geosmin into [...]