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In this study, we examine a modified heat equation with memory and nonlinear source. The source function is considered under two different conditions, the global Lipschitz and the exponential growth functions. For the first condition, a special weighted Banach space is applied to deduce a desired result without any assumption on sufficiently small time and initial data. For the second condition of exponential growth, we apply the Moser–Trudinger inequality to cope with the source function, and a special time-space norm to deduce the unique existence of a global solution in regard to sufficiently small data. The main objective of this work is to prove the global existence and uniqueness of mild solutions. Besides the solution techniques, our main arguments are also based on the Banach fixed point theorem and linear estimates for the mild solution. The highlight of this study is that it is the first work on the global well-posedness for the mild solution of the fractional heat conduction with memory and nonlinear sources.

In this article, we considered the pseudo-parabolic equation with Caputo-Fabrizio fractional derivative. This equation has many applications in different fields, such as science, technology, and so on. In this article, we gave the formula of mild solution, which is represented in the form of Fourier series by some operators . In the linear case, we investigated the continuity of the mild solution with respect to the fractional order. For the nonlinear case, we investigated the existence and uniqueness of a global solution. The main proof technique is based on the Banach fixed point theorem combined with some Sobolev embeddings. For more detailed, we obtained two other interesting results: the continuity of mild solution with respect to the derivative order and the convergence of solution as the coefficient k approaches to zero.

The objective of this study was to determine the semen cryopreservation capacity of BBB bulls in Hanoi-Vietnam. Research conducted on the fresh semen collected from 05 BBB bulls. Results showed that semen color was normal (milky white, ivory white, ivory yellow), semen volume ranged from 6.35 mL to 7.48 mL (P

The objective of this study was to determine the right conditions for the separation of Blanc-Blue-Belge bovine sperm (BBB) by swim-up mothed; determine the maturity of hybrid Zebu bovine eggs; and culture of embryos after in vitro fertilization. After 60-80 minutes of swim-up in CAP-05, BBB bovine sperms were healthy, straight movement and separated with a concentration of 106 sperm/ml. Hybrid Zebu bovine eggs developed and matured in the maturation medium with the basic medium TCM-199 supplemented with 10% calf serum, FSH (0.75 µg / ml), LH (0.15 µg / ml) and Estradiol (2.5 µg / ml), the results showed that the IVM-08 medium had significantly higher maturation rates than IVM-03, the proportion of mature eggs reached 71,11% compared to 51.69%, respectively (P

Synthesis of reduced graphene oxide/TiO₂ nanotubes (rGO/TNTs) composite is being attended. However, the synthesis of rGO/TNTs composite directly from graphite oxide with a greener approach is still challenging. In this study, we directly synthesized rGO/TNTs composite by a simple method from graphite oxide and titanium dioxide nanotube (TNTs) powder without involving any assistant agents. The formation of the graphene oxide (GO) was confirmed by X-ray diffraction (XRD) pattern, transmission electron microscope (TEM) image, Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Besides, photoluminescence analysis (PL) was conducted to determine the defects of materials. The methylene blue (MB) photodegradation efficiency under visible light of rGO/TNTs composite achieved 80% after 180 min. In addition, the key of the photocatalytic mechanism of rGO/TNTs under visible light was systematically investigated via trapping experiments.

Literacy overview shows that almost all of valuation researches for heritages have built demand curves as that of private goods. We argue that heritages are high-end purity public goods. A heritage valuation research would yield more accurate results if the demand curve could be built as that of a public good. This paper presents arguments of the superiority of the public good demand curve over that of private good in the scope of heritage valuation, and initially apply for Zonal Travel Cost Method (ZTCM) in valuating Hoi An, a World Heritage in Central of Vietnam, to look for evidences of such superiority. Evidences show that: (i) the relationship between visits and travel cost could be represented more accurately by the public good’s demand curve rather than the private good’s one; (ii) To build the demand curve for such a World Heritage (tourists are inhomogeneous) it requires additional technique to minimize potential distortions, in which the purchasing power parity ratio (PPP ratio) has been used to adjust inconsistence of actual traveling costs; (iii) The values of Hoi An has been valuated at US $ 4,255,724,958 USD in accordance with its public good’s demand curve, shows 206.6% higher than the value computed according to the private goods’ demand curve.

Synthesis of reduced graphene oxide/TiO₂ nanotubes (rGO/TNTs) composite is being attended. However, the synthesis of rGO/TNTs composite directly from graphite oxide with a greener approach is still challenging. In this study, we directly synthesized rGO/TNTs composite by a simple method from graphite oxide and titanium dioxide nanotube (TNTs) powder without involving any assistant agents. The formation of the graphene oxide (GO) was confirmed by X-ray diffraction (XRD) pattern, transmission electron microscope (TEM) image, Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Besides, photoluminescence analysis (PL) was conducted to determine the defects of materials. The methylene blue (MB) photodegradation efficiency under visible light of rGO/TNTs composite achieved 80% after 180 min. In addition, the key of the photocatalytic mechanism of rGO/TNTs under visible light was systematically investigated via trapping experiments.

In this study, TiO2 nanotubes (TNTs) were synthesized via a hydrothermal process and characterized by high-resolution transmission electron microscopy (HR-TEM) images, selected area electron diffraction (SAED) pattern, and photoluminescence (PL) analysis. The NO removal photocatalytic activity of the hydrothermally synthesizedTNTs was surveyed systematically. The hydrothermally synthesizedTNTs have shown an efficient NO photodegradation which is approximately 4 times higher than that of P25 and an excellent photostability under visible light after 5 cycles. Furthermore, reactive radicals mainly involved in the photocatalytic reaction were identified by electron spin resonance (ESR) study, leading to a better understanding of the photocatalytic mechanism of the hydrothermally synthesized TNTs.

In this paper, we show that health insurance and health-care services have been expanded in Viet Nam over the past decade and had the potential to reach various groups of older persons (defined as those aged 60 or more). Yet, a number of challenges still remain that greatly influence the current health-care system as regards affordability and adequate service provision. The most critical of these issues is that the most vulnerable groups among older persons have lower access rates and a greater financial burden (that is, out-of-pocket expenses). To deal with those issues, we suggest certain policy directions, including developing communal health systems and guaranteeing the financial sustainability of the health insurance fund by monitoring both service providers and users.

Visible-light-driven graphite-like carbon nitride/TiO2 nanotubes (g-C3N4/TNTs) heterostructures were synthesized by hydrothermal and calcination processes. The g-C3N4/TNTs heterostructures with the different weight ratios of g-C3N4 to TNTs, from 0.5 wt% to 5 wt%, were characterized by modern methods of physical-chemical analysis. The photocatalytic activity of materials was evaluated by the degradation of methylene blue (MB) dye in aqueous under the visible light. Results showed that the MB photocatalytic degradation performance of the g-C3N4/TNTs heterostructures was enhanced, and that of the 2% g-C3N4/TNTs witnessed the highest efficiency (81%, 180 min). The photocatalytic activity was improved, thanks to the extended optical absorption range and enhanced separation of the photoinduced electron-hole pairs. Furthermore, the band alignment of the g-C3N4/TNTs heterostructures was determined by the preliminary calculation.

We evaluated whether sex affects the steady-state pharmacokinetics of the antimalarial drugs, primaquine and doxycycline, in healthy subjects. Seventeen male and 17 female healthy Vietnamese subjects were administered 30 mg (base) of primaquine daily for 14 days. After a 2-week washout period, 14 male and 14 female subjects were administered 100 mg (base) of doxycycline daily for 14 days. Women had significantly higher median values of C(max) (212 versus 122 ng/mL, P< 0.001) and AUC(0-24) (1,909 versus 917 ng . h/mL, P < 0.001) of primaquine compared with men. Other than a longer t(max) in women, no sex-related differences were seen in the pharmacokinetics of doxycycline. The primaquine pharmacokinetic data suggest that women have increased exposure to primaquine, which may put them at increased risk for toxicity when administered the same maintenance dose as men. The similar pharmacokinetics of doxycycline between the two sexes justifies the same maintenance dose.

We present a sampling method called, CacheDiff, that has both time and space complexity of O(k) to randomly select k items from a pool of N items, in which N is known.

Aims To evaluate the effects of gender, food and grapefruit juice on the pharmacokinetics of primaquine in healthy subjects. Methods In a randomized, two-phase cross-over study, 10 male and 10 female healthy Vietnamese subjects were administered 30 mg primaquine in the fasting state or with food, followed by administration of primaquine with grapefruit juice. Results The pharmacokinetics of primaquine were comparable between male and female subjects, with geometric mean ratios of Cmax = 0.89 [95% confidence interval (CI) 0.65, 1.22] and AUC = 0.80 (95% CI 0.56, 1.15). The mean CL/F of primaquine was slightly higher in males than in females [0.52 l h−1 kg−1vs. 0.43 l h−1 kg−1, mean difference of 0.09 (95% CI –0.10, 0.28), P = 0.32]. When compared with fasting state values, food increased the geometric mean Cmax of primaquine by 26% (95% CI 12, 40) and the AUC by 14% (95% CI 3, 27). Similarly, grapefruit juice increased the geometric mean Cmax by 23% (95% CI 4, 45) and the AUC by 19% (95% CI 4, 37). Conclusions The disposition of primaquine was comparable between genders, suggesting no need to modify the dose of primaquine for malaria treatment or prophylaxis. Food increased the oral bioavailability of primaquine, which may lead to higher antimalarial efficacy. Grapefruit juice increased the bioavailability of primaquine, with marked interindividual differences suggesting that people should not take primaquine with grapefruit juice.

Food has been reported to increase the bioavailability of mefloquine in healthy volunteers, but its role in increasing blood mefloquine concentrations in malaria patients treated with mefloquine is unclear. In this study, we compared blood mefloquine concentrations after the administration of artesunate (8 mg/kg) and mefloquine (15 mg/kg) over 12h with either a low-fat (approximately 3g of fat) or high-fat (approximately 30 g of fat) meal for the treatment of Plasmodium falciparum malaria in 12 Vietnamese patients. No statistical differences were detected in the following kinetic parameters between the low-fat (n=6) and high-fat (n=6) groups, respectively: maximum blood mefloquine concentrations (2838+/-531 ng/ml and 2556+/-657 ng/ml, 95% CI -486 to 1050 ng/ml, P=0.43) and the area under the blood mefloquine concentration versus time curves (246.8+/-58.3 microg.h/ml and 238.3+/-28.4 microg.h/ml, 95% CI -50.5 to 67.5 microg.h/ml, P=0.75). A fatty meal does not appear to increase the bioavailability of mefloquine in malaria patients and should not affect the response of malaria infections to treatment.

Background In Vietnam, the artemisinin-based combination therapy (ACT) of dihydroartemisinin-piperaquine is currently used for first-line treatment of uncomplicated Plasmodium falciparum malaria. However, limited efficacy and tolerability data are available on alternative forms of ACT in Vietnam in case there is a reduction in the susceptibility of dihydroartemisinin-piperaquine. A study was conducted to compare the efficacy and tolerability of two fixed-dose formulations of ACT, artemisinin–piperaquine (Artequick®, ARPQ) and artesunate-amodiaquine (Coarsucam™, ASAQ) for the treatment of P. falciparum malaria in south-central Vietnam. Methods A randomized, open-label trial was conducted comparing the efficacy of a two-day regimen of ARPQ (~2.8 mg/kg artemisinin plus ~17.1 mg/kg of piperaquine per day) and a three-day regimen of ASAQ (~4.7 mg/kg of artesunate plus ~12.6 mg/kg of amodiaquine per day) for the treatment of children and adults with uncomplicated falciparum malaria. Primary efficacy endpoint was day 42, PCR-corrected, parasitological cure rate. Secondary endpoints were parasite and fever clearance times and tolerability. Results Of 128 patients enrolled, 63 were administered ARPQ and 65 ASAQ. Of the patients who completed the 42 days follow-up period or had a recurrence of malaria, 55 were on ARPQ (30 children, 25 adults) and 59 were on ASAQ (31 children, 28 adults). Recrudescent parasitaemia was PCR-confirmed for one patient in each treatment group, with cure rates at day 42 of 98% (95% CI: 88–100) for both forms of ACT. The median parasite clearance time was significantly slower in the ARPQ group compared with the ASAQ group (48 h vs. 36 h, Pvs. 24 h, P = 0.07). The two forms of ACT were well tolerated with no serious adverse events. Conclusion Both forms of ACT were highly efficacious in the treatment of uncomplicated P. falciparum malaria. Although the two-day course of ARPQ was equally as effective as the three-day course of ASAQ, parasite and fever clearance times were shorter with ASAQ. Further studies are warranted in different regions of Vietnam to determine the nationwide efficacy of ASAQ. Trial registration Australian New Zealand Clinical Trials Registry Number, ACTRN12609000816257

Artesunate-amodiaquine (AAQ) is efficacious for the treatment of uncomplicated Plasmodium falciparum malaria in Africa, but little is known about its efficacy in Southeast Asia. We compared the efficacy of dihydroartemisinin-piperaquine (DHP) and AAQ against falciparum malaria in central Vietnam.Open, randomized clinical trial of 116 patients (36 children aged 6-14 years, 80 adults aged 15-60 years) were randomly allocated a 3-day course of either DHP (approximately 2.3 mg/kg dihydroartemisinin plus approximately 18.5 mg/kg of piperaquine per day) or AAQ (approximately 4.4 mg/kg of artesunate plus approximately 10.6 mg/kg of amodiaquine per day). The follow-up period was 42 days.The two drug combinations were well tolerated by all age groups with no obvious drug associated adverse events. Of the patients who completed 42 days of follow-up, 49 were on DHP (15 children, 34 adults) and 49 were on AAQ (14 children, 35 adults). The 42 day cure rates adjusted for reinfection identified by PCR genotyping for the two groups were similar [100% (49/49) and 98% (48/49) for DHP and AAQ, respectively]. With fewer reinfections, DHP appears to possess greater post-treatment prophylactic activity than AAQ.AAQ, an inexpensive artemisinin-based combination, could be an additional option to DHP for the treatment of multidrug-resistant falciparum malaria in Vietnam.

The two fixed-dose combinations of dihydroartemisinin and piperaquine (Artekin and Arterakine) were found to be bioinequivalent in healthy Vietnamese subjects. However, because the peak plasma concentrations and areas under the concentration-time curves of dihydroartemisinin and piperaquine were only marginally different between the two formulations, similar therapeutic efficacies are expected in the treatment of malaria infections.

We compared plasma maximum concentration (Cmax) and area under the concentration-time curve (AUC) of the antimalarial drug piperaquine in 26 healthy Vietnamese subjects after treatment with either a single oral dose of 500 mg (n = 6) or 1,000 mg (n = 6) of piperaquine phosphate and a three-day course of 500 mg of piperaquine/ day in the fasting state (n = 7) or with food (approximately 17 g fat) (n = 7). The geometric mean plasma Cmax and AUC((0-28)) was 2.8-fold (200 ng/mL versus 70 ng/mL) and 1.9-fold (5,736 ng x h/mL versus 2,999 ng x h/mL), respectively, and higher in subjects receiving the 1,000-mg dose than in those receiving the 500-mg dose. The geometric mean Cmax and AUC((0-28)) was 1.7-fold (198 ng/mL versus 119 ng/mL) and 1.4-fold (11,187 ng x h/mL versus 7,954 ng x h/mL) higher in the fed state than in the fasting state. Piperaquine AUC was proportional to the two doses tested and a moderate-fat meal enhanced the bioavailability of piperaquine by 41%, which should improve the therapeutic efficacy of this drug.

Summary The standard adult treatment regimen for Plasmodium vivax malaria is chloroquine (1500 mg over 3 d) plus primaquine (15 or 30 mg daily for 14 d), but patient compliance tends to be poor with the lengthy course. Preliminary observations are reported on the efficacy of a shorter treatment course – artesunate (200 mg twice a day for 2 d) plus primaquine (22.5 mg base twice a day for 7 d) – given to 28 adult patients infected with P. vivax in Viet Nam. All patients responded quickly to treatment with mean (SD) parasite and fever clearance times of 14.2 (4.0) and 18.6 (8.4) h, respectively. The high dose of primaquine was generally well tolerated, and only one patient (3.6%) had a recurrence of parasitaemia during 28 d of follow-up. As most patients infected with Southeast Asian strains of P. vivax have their first relapse within 28 d after treatment with rapidly eliminated blood schizonticides, the absence of parasitaemia in the remaining 27 patients suggests that this drug regimen was active against both blood and liver stages. Further studies are needed to confirm that this rapidly acting, short artesunate–primaquine regimen can result in better patient compliance and treatment outcomes than the chloroquine–primaquine regimen.

Micronutrient deficiencies remain common in preschool children in developing countries. Interventions focus on single micronutrients and often lack effectiveness. Weekly instead of daily supplementation may improve effectiveness.The efficacy of weekly and daily supplementation in reducing anemia prevalence and in improving the zinc, vitamin A, and growth status of 6-24-mo-old Vietnamese children was investigated.In this double-blind, placebo-controlled trial, the daily group (n = 55) received 8 mg elemental Fe (as iron sulfate), 5 mg elemental Zn (as zinc sulfate), 333 microg retinol, and 20 mg vitamin C 5 d/wk for 3 mo. The weekly group (n = 54) received 20 mg Fe, 17 mg Zn, 1700 microg retinol, and 20 mg vitamin C once a week. A third group (n = 54) received a placebo only. Venous blood samples were collected at the start and end of the supplementation period and anthropometric measurements were taken at the start and 3 mo after the end of supplementation.At baseline, 45.6% of subjects had hemoglobin concentrations110 g/L, 36.3% had zinc concentrations10.71 micromol/L, and 45.6% had retinol concentrations0.70 micromol/L. Hemoglobin, retinol, and zinc concentrations of both the weekly and daily groups increased similarly compared with the placebo group (P0.001). There was no significant difference in growth between the supplemented groups and the placebo group. However, the height-for-age of subjects stunted at baseline increased with z scores of 0.48 (P0.001) and 0.37 (P0.001) for the daily and weekly groups, respectively.Weekly and daily supplementation improved hemoglobin, zinc, and retinol concentrations similarly. Neither intervention affected growth of the overall population, but growth of children stunted at baseline was improved through both types of supplementation.

Polypyrrole nanowires were electrochemically synthesised on platinum electrode at ambient temperature. The potentiostatic potential was set at 0.75 V in the presence of gelatin as soft mould. The whole process only took few hundred seconds. The morphologies, chemical composition and conductivity of nanowires were evaluated by means of Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and cyclic voltammetry (CV). The obtained nano-wire is around 50 nm in diameter with large surface, good conductivity. By surface enhanced Raman spectroscopy, the amine groups of polypyrrole were thought to be orientated upwards into the analyte which may facilitate the direct binding with DNA in DNA sensor.