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The mesoporous gamma-alumina (γ-Al2O3) synthesized via evaporation-induced self-assembly method (EISA) using inorganic salt, Al(NO3)3·9H2O precursor and water-ethanol solvent mixture was implemented as a support for Co catalyst in methane dry reforming at 973–1073 K under 1 atm. The γ-Al2O3 support possessed filament-shaped morphology with surface area of 173.4 m2 g−1 and cobalt nanoparticles were successfully dispersed on support with small crystallite size of 7.8 nm. The stability of 10%Co/Al2O3 was evident for CH4 and CO2 conversions at 1023 and 1073 K. CH4 conversion could reach to 76.2% while 81.6% was observed for CO2 conversion at 1073 K. Although graphitic and amorphous carbons were unavoidably formed on used catalyst, 10%Co/Al2O3 exhibited an outstanding performance comparable to noble metals with the desired ratio of H2/CO for downstream Fischer-Tropsch process.

The promotional La2O3 effect on the physicochemical features of mesoporous alumina (MA) supported cobalt catalyst and its catalytic performance for methane dry reforming (MDR) was examined at varied temperature and stoichiometry feedstock. The Co3O4 nanoparticles were evidently scattered on fibrous mesoporous alumina with small crystal size of 8–10 nm. The promotion behavior of La2O3 facilitated H2-reduction by providing higher electron density and enhanced oxygen vacancy in 10%Co/MA. The addition of La2O3 could reduce the apparent activation energy of CH4 consumption; hence, increasing CH4 conversion up to 93.7% at 1073 K. The enhancement of catalytic activity with La2O3 addition was also due to smaller crystallite size, alleviated H2-reduction and the basic character of La2O3. Lanthanum dioxycarbonate transitional phase formed in situ during MDR was accountable for mitigating deposited carbon via redox cycle for 17–30% relying on reaction temperature. Additionally, the oxygen vacancy degree increased to 73.3% with La2O3 promotion. The variation of H2/CO ratios within 0.63–0.99 was preferred for downstream generation of long-chain olefinic hydrocarbons.

International audience; In the Mekong Delta region of Vietnam, small-scale chicken farming is common. However, high levels of disease or mortality in such flocks impair eco- nomic development and challenge the livelihoods of many rural households. We investigated 61 diseased small-scale flocks (122 chickens) for evidence of infec- tion with 5 bacteria, 4 viruses, and helminths. Sero- logical profiles (ELISA) were also determined against 6 of these pathogens. The aims of this study were the following: (1) to investigate the prevalence of different pathogens and to compare the probability of detection of bacterial pathogens using PCR and culture; (2) to investigate the relationship between detection of or- ganisms in birds’ tissues and the observed morbidity and mortality, as well as their antibody profile; and (3) to characterize risk factors for infection with specific viral or bacterial pathogens. We used PCR to test for viral (viruses causing infectious bronchitis [IB], highly pathogenic avian influenza [HPAI], Newcastle disease, and infectious bursal disease [IBD]) and bacterial pathogens (Mycoplasma gallisepticum, Pas- teurella multocida, Avibacterium paragallinarum, and Ornithobacterium rhinotracheale [ORT]). The latter two were also investigated in respiratory tissues by conventional culture. Colisepticemic Escherichia coli was investigated by liver or spleen culture. In 49 of 61 (80.3%) flocks, at least one bacterial or viral pathogen was detected, and in 29 (47.5%) flocks, more than one pathogen was detected. A. paragallinarum was detected in 62.3% flocks, followed by M. gallisepticum (26.2%), viruses causing IBD (24.6%) and IB (21.3%), septicemic E. coli (14.8%), ORT (13.1%), and HPAI viruses (4.9%). Of all flocks, 67.2% flocks were colonized by helminths. Mortality was highest among flocks infected with HPAI (100%, interquartile range [IQR]: 81.6– 100%) and lowest with flocks infected with ORT (5.3%, IQR: 1.1–9.0%). The results indicated slight agreement (kappa 0.167) between detection by PCR and culture for both A. paragallinarum and ORT, as well as be- tween the presence of cestodes and ORT infection (kappa 5 0.317). Control of A. paragallinarum, viruses causing HPAI, IBD, and IB, M. gallisepticum, and gastrointestinal helminths should be a priority in small- scale flocks.

The unpromoted and B-promoted 10%Ni/SBA-15 catalysts synthesized via sequential incipient wetness impregnation approach were assessed for combined steam and CO2 reforming of methane (CSCRM) at various reaction temperatures of 973–1073 K and stoichiometric feed composition. An expected and noteworthy drop in mean NiO crystallite size and BET surface area with boron promotion from 1% to 5%B loading could be due to the agglomeration of B2O3 particles and deboration reaction during calcination and hence blocking mesopores of SBA-15 support at elevated B composition. The complete NiO reduction to metallic Ni0 form was achieved during H2 activation and the reduction temperature of NiO phase was shifted towards higher temperature with B-addition owing to enhancing interaction between the acidic B2O3 and basic NiO phases. For all reaction temperature employed, 3%B appeared to be the optimal promoter loading in terms of reactant conversions and 3%B-10%Ni/SBA-15 catalyst revealed the greatest H2 yield (69.4%) at 1073 K. In addition, CH4 and CO2 conversions were enhanced about 23.2% and 32.4%, correspondingly with rising reaction temperature from 973 to 1073 K. Ratio of H2 to CO varied from 1.26 to 2.71 and the desired H2/CO ratio of about 2 favored for Fischer-Tropsch synthesis was achieved on 3%B-10%Ni/SBA-15 sample at 973 K. Boron promoter suppressed graphitic carbon formation and the amount of carbonaceous deposition was reduced about 4 times. Noticeably, 3%B-10%Ni/SBA-15 was also resilient to metallic Ni0 re-oxidation throughout CSCRM.

Excessive antimicrobial usage and deficiencies in hygiene in meat production systems may result in undesirable human health hazards, such as the presence of antimicrobial drug residues and non-typhoidal Salmonella (NTS), including antimicrobial resistant (AMR) NTS. Recently, Vietnam has witnessed the emergence of integrated intensive animal production systems, coexisting with more traditional, locally-sourced wet markets. To date no systematic studies have been carried out to compare health hazards in beef, pork and chicken in different production systems. We aimed to: (1) estimate the prevalence of antimicrobial residues in beef, pork and chicken meat; (2) investigate the prevalence and levels of NTS contamination; and (3) investigate serovar distribution and AMR against critically important antimicrobials by animal species and type of retail (wet market vs. supermarket) in Vietnam. Fresh pork, beef and chicken meat samples (N = 357) sourced from wet markets and supermarkets in Ho Chi Minh City (HCMC), Hanoi and Dong Thap were screened for antimicrobial residues by PremiTest, and were further investigated by Charm II. Samples from HCMC (N = 113) were cultured using ISO 6579:2002/Amd 1:2007. NTS bacteria were quantified using a minimum probable number (MPN) technique. NTS isolates were assigned to serovar by Multilocus Sequence Typing (MLST), and were investigated for their phenotypic susceptibility against 32 antimicrobials. A total of 26 (7.3%) samples tested positive by PremiTest (9.5% beef, 4.1% pork and 8.4% chicken meat). Sulfonamides, tetracyclines and macrolides were detected by Charm in 3.1%, 2.8% and 2.0% samples, respectively. Overall, meat samples from wet markets had a higher prevalence of residues than those from supermarkets (9.6% vs. 2.6%) (p = 0.016). NTS were isolated from 68.4% samples from HCMC. Chicken samples from wet markets had by far the highest NTS counts (median 3.2 log MPN/g). NTS isolates displayed high levels of resistance against quinolones (52.2%) and β-lactams (49.6%), but low levels against 3rd generation cephalosporins (4.4%) and aminoglycosides (0.8%). The highest adjusted prevalence of multidrug resistance (MDR) corresponded to isolates from chicken meat and pork (OR 8.3 and 1.8, respectively) (baseline = beef). S. Kentucky was the most common serovar identified (11 from chicken, 1 from beef) and 91.7% isolates was MDR. 11/12 isolates corresponded to ST198, a worldwide-disseminated multi-resistant NTS clone. We recommend stepping up policy measures to promote responsible antimicrobial use in animal production, as well as awareness about withdrawal periods to limit the hazard of residues in animal products, and improving slaughtering/hygiene procedures to limit cross-contamination with NTS, particularly in poultry wet markets., Highlights • Antimicrobial residues were found in 7.3% meat samples (9.6% in meat from wet markets and 2.6% in meat from supermarkets). • Over two thirds (68.4%) of meat samples were contaminated with non-typhoidal Salmonella; 52.2% of isolates were multidrug resistant. • Chicken meat from wet markets had the highest loads of contamination with non-typhoidal Salmonella (median 3.2 log MPN/g in positive samples). • Multidrug resistance was highest in Salmonella from chicken meat, and lowest in beef; the type of retail was not linked to increased resistance. • The most commonly identified serovar was multidrug resistant Salmonella Kentucky ST198, with high levels resistance against β-lactams and quinolones.

Highlights • Vietnam's EPI has caused sharp decreases in vaccine-preventable disease incidence. • EPI may have saved over 370,000 lives. • EPI represents good value for money., Introduction Countries like Vietnam transitioning to middle-income status increasingly bear the cost of both existing and new vaccines. However, the impact and cost-effectiveness of the Expanded Programme on Immunization (EPI) as a whole has never been assessed on a country level. Methods Data on vaccine-preventable disease incidence and mortality from Vietnam's national surveillance was analysed to estimate the likely impact that vaccination in 1980–2010 may have had. Adjustment for under-reporting was made by examining trends in reported mumps incidence and in case-fatality risks for each disease. The same data were separately analysed using the Lives Saved Tool (LiST) to give an alternative estimate of impact. The financial cost of EPI in 1996–2010 was also estimated from the perspective of service provider. Results National surveillance data suggests that up to 5.7 million diseases cases and 26,000 deaths may have been prevented by EPI. Analysis using LiST suggests that even more deaths (370,000) may have been prevented by measles and pertussis vaccination alone. The cost-effectiveness of EPI is estimated to be around $1000–$27,000 per death prevented. Conclusion Two separate approaches to assessing EPI impact in Vietnam give different quantitative results but a common conclusion: that EPI has made a substantial impact on mortality and represents good value for money.

Direct competitive enzyme-linked immunosorbent assay (ELISA) for 2,4-dichlorophenoxyacetic acid (2,4-D) was developed. Varying the concentrations of monoclonal anti-2,4-D-antibody and the conjugate of soybean peroxidase and 2,4-D the conditions of ELISA performance were optimised. The chemiluminescent method based on peroxidase-catalysed oxidation of luminol was applied to measure the enzyme activity of the conjugate. A mixture of 3-(10′-phenothiazinyl)propane-1-sulfonate and 4-morpholinopyridine was used as potent enhancer of chemiluminescence signal. It was shown that the values of the lower detection limit, IC 50 and the working range were 1.5, 64.0, and 6.5–545 ng/mL, respectively. The recovery values of CL-ELISA from 10 spiked samples of oranges ( n = 5) and mandarins ( n = 5) cultivated in green house without use of 2,4-D and containing different 2,4-D concentrations (10–300 ng/mL) were ranged from 92% to 104% that indicated on the absence of matrix effect for the fruit extracts of interest. Determination of 2,4-D in peel of five oranges and five mandarins purchased from stores in Vietnam showed that 2,4-D content in oranges fruits (79–104 μg/kg) was significantly higher than that in mandarins (1.66–2.82 μg/kg).

This Article analyzes the current provisions on cartels in Vietnamese Competition Law of 2004 and provides some comments about the approaches of this Law in dealing with cartels.

This paper discusses how principle of contractual freedom in Vietnam should be modified to better protect consumers in its developing market economy.

This paper is conducted in order to contribute my part to answering questions which are encountering Vietnamese law-makers in designing the country's first competition law. This paper is concerned with the issue of designing criteria to determine whether a cartel (an agreement among competitors to fix price, limit output, divide market or rig bids) is legal or illegal for Vietnam based on some lessons from the experiences in designing and enforcing those criteria in the 3 most influential jurisdictions of competition law in the world, i.e. the U.S, EC and Japan.This paper shows that all criteria used to assess the illegality of a cartel in the U.S., EC and Japan are closely related to requirements about efficiency, market power or administrative ability.Loyal to the conviction that only enterprise that possesses substantial market power can harm competition process in the market and responding to the request of a less stringent competition law by the business community, the Japanese competition law requires that all illegal cartels must meet the two requirements, namely causing "substantial restraint of competition" and "contrary to the public interest". The existence of the cartel itself is therefore not enough for its illegality. In all cartel cases, the existence of market power must be proved by taking complicate steps such as defining relevant product market, relevant geographic market, identifying entry and exit barriers, etc. This approach makes the process of enforcement of anti-cartel rules lengthy and expensive.The U.S. antitrust law and EC competition law employ a simpler approach to assess the illegality of cartels. By expressly adopting ancillary restraint doctrine and per se rule, the U.S. anti-cartel rule is that all naked cartels are per se illegal. The existence of such cartel itself is sufficient for its illegality. No further inquiry is needed and no defense is allowed. By expressly adopting ancillary restraint doctrine and regarding naked cartels as agreements which have as their object the "restriction of competition", the EC anti-cartel rule is also quite simple: all naked cartels are generally illegal. The existence of naked cartels is sufficient for their illegality. No further inquiry is needed and almost no defense is allowed. Clearly, the enforcement of anti-cartel rules in the U.S. and EC is less expensive and less complicate than that of Japanese counterpart. Not expressly recognizing the ancillary restraint doctrine, the Drafting Committee of Competition Law of Vietnam proposes an anti-cartel rule that only cartel with the combined market share of not less than 30% (except for bid-rigging) can be considered as illegal. This paper shows that the approach of the Drafting Committee would create unnecessary steps in the application of anti-cartel rule. This paper proposes that the Competition Law of Vietnam should expressly adopt the ancillary restraint doctrine and per se rule in determining whether a cartel is illegal or not. The illegality of ancillary restraint should be analyzed by its necessity for the smooth implementation of the main efficiency-enhancing transaction or activity. Naked cartels should be treated as per se illegal. This approach is especially appropriate in the context it is the first time Vietnam adopts a competition law.