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A large number of studies on organophosphate esters (tri-OPEs) in marine organisms have not assessed the simultaneous occurrence of tri-OPEs and their metabolites (di-OPEs) in these species. This research investigated the concentration and geographical distribution of 15 tri-OPEs and 7 di-OPEs in 172 samples of Pampus argenteus that were collected annually from 2021 to 2023 at three distinct locations along the Vietnamese coast. As a result, tri-OPEs and di-OPEs were detected in numerous fish samples, indicating their widespread spatial and temporal occurrence in marine fish and pointing out the importance of monitoring their levels. The tri-OPEs and di-OPEs ranged within 2.1-38.9 ng g-1 dry weight (dw) and 3.2-263.4 ng g-1 dw, respectively. The mean concentrations of tri-OPEs ranged from 0.4 (TIPrP) to 5.4 ng g-1 dw (TBOEP), with TBOEP and TEHP having the highest mean values. In addition, the profiles of tri-OPEs in fish exhibited a descending order: Σalkyl OPEs > ΣCl-alkyl OPEs > Σaryl OPEs. The di-OPEs, namely BEHP and DMP, had the highest mean levels, measuring 33.4 ng g-1 dw and 23.8 ng g-1 dw, respectively. Furthermore, there have been significant findings of strong positive correlations between di-OPEs and tri-OPE pairs (p < 0.05). It is worth noting that there is a noticeable difference in the composition of tri-OPEs between the North and other regions. Despite these findings, the presence of OPE-contaminated fish did not pose any health risks to Vietnam's coastal population.
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Monitoramento Ambiental , Ésteres , Organofosfatos , Perciformes , Poluentes Químicos da Água , Animais , Vietnã , Organofosfatos/análise , Organofosfatos/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Ésteres/análise , Ésteres/metabolismo , Perciformes/metabolismo , Análise Espaço-Temporal , Peixes/metabolismo , População do Sudeste AsiáticoRESUMO
This paper studies the security and reliability of the power splitting (PS)-based relaying in the Internet of Things (IoT) networks with the help of a jammer. Based on the considered system model, we derive outage probability (OP) and intercept probability (IP) under two distinguished schemes, namely, the static PS relaying (SPSR) scheme and the dynamic PS relaying (DPSR) scheme. More precisely, the PS ratio of the former is a constant number, while the latter is optimally adjusted in order to minimize the OP and counts only on the channel gain of the second hop. Numerical results are provided to not only verify the accuracy of the proposed mathematical framework but also identify the trends of both OP and IP with respect to several important parameters. Our findings unveil that the OP and IP have contradictory behavior with respect to the transmit power and number of sources. Moreover, the performance of the DPSR scheme is superior to that of the SPSR scheme.
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Parabens (p-hydroxybenzoic acid esters) commonly used preservatives (in cosmetics, pharmaceuticals, and foods) can pose potential effects on environmental health. In this study, seven parabens were quantified in marine fish samples using an ultra-high performance liquid chromatography triple quadrupole mass spectrometer (UHPLC-MS/MS) system. Parabens in the fish samples were extracted and purified by a rapid, simple, and effective procedure comprising sample homogenization with solvent, solid-phase extraction clean-up, and solvent evaporation. Results demonstrated that the recoveries of seven compounds (with relative standard deviation < 15%) were 88-103% in matrix-spike samples and 86-105% in surrogate standards. The method detection limits and method quantification limits of seven parabens were 0.015-0.030 and 0.045-0.090 ng/g-ww (wet weight), respectively. The optimized method was applied to measure the concentration of parabens in the 37 marine fish samples collected from Vietnam coastal waters. The concentration ranges of seven parabens found in round scad and greater lizardfish samples were 6.82-25.3 ng/g ww and 6.21-17.2 ng/g-ww, respectively. Among parabens, methylparaben accounted for the highest contribution in both fish species (43.2 and 44.9%, respectively). Based on the measured concentrations of parabens in marine fish samples, the estimated daily intake was calculated for children and adults with the corresponding values of 0.0477 µg/kg/day and 0.0119 µg/kg/day, respectively. However, the presence of parabens in Vietnamese marine fish may not pose a significant risk to human health.
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Parabenos , Espectrometria de Massas em Tandem , Adulto , Criança , Animais , Humanos , Parabenos/análise , Peixes , Conservantes Farmacêuticos , Cromatografia Líquida de Alta Pressão/métodos , SolventesRESUMO
Many patients in Switzerland wish to die at home. Nevertheless, end-of-life home care requests specific considerations such as basic palliative care knowledge among health care professionals and a well-organized and coordinated health care network which needs to be put in place as early as possible. Beforehand, an open discussion with the patient and the caregiver about their expectations and wishes is mandatory. Furthermore, anticipation about the evolution of the disease, potential symptoms, material requests, psychological and social barriers is the key element to provide home palliative care until the end of life. Most "cantons from the Romandie" have a large offer in health care services allowing for home end-of-life care.
Une fin de vie à domicile est souhaitée par beaucoup de patients en Suisse, mais sa mise en place nécessite entre autres des connaissances en matière de soins palliatifs et l'organisation précoce d'un réseau de soins interprofessionnel bien organisé et coordonné. Un prérequis est également une discussion ouverte avec le patient et son entourage quant aux attentes et souhaits de soins. L'anticipation par rapport à différents sujets tels que l'évolution de la maladie, les symptômes potentiels, les besoins en matériel, les difficultés psychiques et les problématiques sociales est l'élément clé pour une réussite d'une fin de vie à domicile. Plusieurs cantons romands offrent une large gamme de soins permettant un maintien au domicile jusqu'au décès.
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Serviços de Assistência Domiciliar , Assistência Terminal , Humanos , Cuidados Paliativos , Morte , Cuidadores/psicologiaRESUMO
Parabens have emerged as the primary preservative of choice in numerous consumer goods, prompting growing apprehension regarding their potential for human exposure. The study employed the optimized QuEChERs sample extraction method and the UHPLC-Q-Orbitrap HRMS system to generate the initial contamination profiles of seven parabens and their four metabolites in a total of 114 fish samples found along the coastline of Vietnam. The findings of the study indicated that methylparaben was the predominant substance detected, exhibiting the highest concentration in the largehead hairtail (Trichiurus lepturus) species at 32.8 ng g-1 dry weight (dw). Additionally, the metabolites with the highest detectable concentrations in the largehead hairtail were found to be 4-HB and 3,4-DHB, with levels of 8822.0 ng g-1 dw and 3490.8 ng g-1 dw, respectively. Besides, the study reveals notable variations in paraben concentrations across three distinct regions in Vietnam, namely the Central, North, and South (Mann-Whitney U test, p < 0.05). The trophic magnification factors (TMF) for methylparaben, ethylparaben, ethyl protocatechuate, and 4-hydroxybenzoic acid exhibited values exceeding 1, indicating substantial biomagnification of these substances within the marine food web of Vietnam. Additionally, noteworthy positive associations have been observed between methylparaben and ethylparaben, as well as their respective metabolites. Based on the findings of the study, it can be concluded that there is no direct impact of seafood consumption on human health in Vietnam.
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Peixes , Parabenos , Animais , Humanos , Parabenos/análise , Vietnã , Bioacumulação , Peixes/metabolismo , Medição de RiscoRESUMO
Background: Chicken infectious anemia (CIA) caused by the CIA virus (CIAV) is considered one of the most important immunosuppressive diseases affecting chickens and recently poses a great economic burden to the poultry industry worldwide. Aim: This study aims to identify the presence of CIAV in the Mekong Delta (MD), Vietnam, and to determine genotypes of CIAVs that are currently circulating in this area. Methods: Organ samples (spleen, liver, and thymus) of 144 chickens suspected with CIA from 47 poultry farms were collected. A total of 47 pooled samples, each containing 2-4 chickens from each farm, were tested for the presence of CIAV. Results: Twenty out of 47 pooled organ samples (pool of 2-4 chickens per farm) were positive for CIAV using polymerase chain reaction targeting the viral VP1 gene. The VP1 amplicons of eight representative CIAVs were subjected to sequencing and genetic characterization. Phylogenetic analysis based on partial VP1 gene sequence revealed that the CIAVs detected in the MD grouped into different genotypes of II, IIIa, and IIIc together with CIAVs previously detected in the northern Vietnam and other Asian countries. The phylogenetic analysis also confirmed that detected CIAVs genetically differed from vaccine strains. In addition, deduced amino acids of the VP1 identified several critical amino acid substitutions in the VP1 protein that are likely associated with the virulence of CIAV. Conclusion: This is the first report to detect and determine the genetic characterization of the circulating CIAVs in the MD. Therefore, this study provides an important understanding of the evolution of CIAVs and highlights the importance of implementing prompt control measures against CIAVs in the MD and Vietnam.
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Vírus da Anemia da Galinha , Infecções por Circoviridae , Doenças das Aves Domésticas , Animais , Galinhas , Vírus da Anemia da Galinha/genética , Vietnã/epidemiologia , Filogenia , Infecções por Circoviridae/veterinária , Doenças das Aves Domésticas/epidemiologiaRESUMO
BACKGROUND: Deep brain stimulation (DBS) surgery for Parkinson's Disease (PD) has become more and more popular in Vietnam. However, the accuracy of implantation and affecting factors are under investigation. The objective of this study is to evaluate the accuracy of the subthalamic nucleus (STN)-DBS electrode implantation technique for treatment PD at Nguyen Tri Phuong Hospital and University Medical Center. To investigate factors related to accuracy. METHODS: We carried out a retrospective analysis of 58 patients with advanced PD who underwent STN-DBS surgery at Nguyen Tri Phuong Hospital and University Medical Center in Ho Chi Minh City, Viet Nam between June 2014 and July 2021 (115 leads total). All patients underwent the procedure with standard frame-based techniques under local anesthesia with microelectrode recording and macrostimuation test. RESULTS: Twenty-six female (44.8%) and thirty-two male (55.2%) patients with a mean age of 60.4 ± 8.3 years old (40-76 years) were included. Of total of 115 electrodes implanted, the mean target error (ΔT), radial error (ΔR), angle error (Δθ) were 1.94 ± 0.73 mm; 1.16 ± 0.69 mm; 2.22 ± 4.24 degrees, respectively. Vector error on each coordinate axis ΔX, ΔY, ΔZ were -0.35 ± 1.02 mm, +0.99 ± 0.82 mm, +0.73 ± 0.99 mm, respectively. There was a statistically significant correlation between subdural air volume, cortical shift, intracranial electrode bending, and accuracy. CONCLUSIONS: The current STN-DBS electrode implantation technique applied in our centers was quite accurate with acceptable error. More clinical trials are necessary to directly compare affecting factors to the accuracy of electrode implantation.
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Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Doença de Parkinson/cirurgia , Núcleo Subtalâmico/cirurgia , Núcleo Subtalâmico/fisiologia , Vietnã , Estimulação Encefálica Profunda/métodos , Estudos Retrospectivos , Eletrodos Implantados , Resultado do TratamentoRESUMO
Halogenated organic pollutants (HOPs), including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and chlorophenols (CPs), were identified in three marine fish species in Vietnam. Total PCBs, OCPs, and CPs concentrations ranged from 4.5 to 711.6 ng g-1 lipid weight (lw), 69.9-2360 ng g-1 lw, and 208.1-3941.2 ng g-1 lw, respectively. CPs were the most frequently detected pollutants in the marine environment of Vietnam of the three HOPs studied, followed by OCPs and PCBs. There are significant differences in HOPs between three types of seafood in Vietnam, including yellowstripe scad, Indian mackerel, and silver pomfret in this study. Notably, the types and amounts of HOPs found in the fish were differently influenced by the economic and industrial activities of the sampled areas. Despite these findings, the consumption of HOP-contaminated fish from the study areas was found not to pose any significant health risks to Vietnam's coastal population.
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Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Bifenilos Policlorados/análise , Poluentes Ambientais/análise , Vietnã , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Hidrocarbonetos Clorados/análise , Peixes , Praguicidas/análise , Músculos/química , Medição de Risco , Éteres Difenil Halogenados/análiseRESUMO
Synchronous bilateral breast cancer (sBBC) occurs after both breasts have been affected by the same germline genetics and environmental exposures. Little evidence exists regarding immune infiltration and response to treatment in sBBCs. Here we show that the impact of the subtype of breast cancer on levels of tumor infiltrating lymphocytes (TILs, n = 277) and on pathologic complete response (pCR) rates (n = 140) differed according to the concordant or discordant subtype of breast cancer of the contralateral tumor: luminal breast tumors with a discordant contralateral tumor had higher TIL levels and higher pCR rates than those with a concordant contralateral tumor. Tumor sequencing revealed that left and right tumors (n = 20) were independent regarding somatic mutations, copy number alterations and clonal phylogeny, whereas primary tumor and residual disease were closely related both from the somatic mutation and from the transcriptomic point of view. Our study indicates that tumor-intrinsic characteristics may have a role in the association of tumor immunity and pCR and demonstrates that the characteristics of the contralateral tumor are also associated with immune infiltration and response to treatment.
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Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/patologia , Mama/patologia , Linfócitos do Interstício Tumoral , Terapia Neoadjuvante , Perfilação da Expressão GênicaRESUMO
The H9 and H6 subtypes of low pathogenicity avian influenza viruses (LPAIVs) cause substantial economic losses in poultry worldwide, including Vietnam. Herein, we characterized Vietnamese H9 and H6 LPAIVs to facilitate the control of avian influenza. The space-time representative viruses of each subtype were selected based on active surveillance from 2014 to 2018 in Vietnam. Phylogenetic analysis using hemagglutinin genes revealed that 54 H9 and 48 H6 Vietnamese LPAIVs were classified into the sublineages Y280/BJ94 and Group II, respectively. Gene constellation analysis indicated that 6 and 19 genotypes of the H9 and H6 subtypes, respectively, belonged to the representative viruses. The Vietnamese viruses are genetically related to the previous isolates and those in neighboring countries, indicating their circulation in poultry after being introduced into Vietnam. The antigenicity of these subtypes was different from that of viruses isolated from wild birds. Antigenicity was more conserved in the H9 viruses than in the H6 viruses. Furthermore, a representative H9 LPAIV exhibited systemic replication in chickens, which was enhanced by coinfection with avian pathogenic Escherichia coli O2. Although H9 and H6 were classified as LPAIVs, their characterization indicated that their silent spread might significantly affect the poultry industry.
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Background: Drug outlets are a vital first point of healthcare contact in low- and middle-income countries (LMICs), but they are often poorly regulated and counter staff may be unqualified to provide advice. This introduces the risk of easy access to potentially harmful products, including unnecessary antimicrobials. Over-the-counter antimicrobial sales are a major driver of antimicrobial resistance (AMR) in LMICs. We aimed to investigate the distribution of different types of drug outlets and their association with socio-economic factors. Methods: We mapped the location of drug outlets in 40 randomly selected geographic clusters, covering a population of 1.96 million people. Data including type of drug outlet, context, operating hours, chief pharmacist name and qualification, and business registration identification were collected from mandatory public signage. We describe the density of drug outlets and levels of staff qualifications in relation to population density, urban vs rural areas, and poverty indices. Findings: We characterised 1972 drug outlets. In the study area, there was an average of 102 outlets/per 100,000 population, compared to the global average of 25. Predictably, population density was correlated with the density of drug outlets. We found that drug outlets were less accessible in rural vs urban areas, and for the poor. Furthermore, for these populations, degree-qualified pharmacists were less accessible and public signage frequently lacked mandatory registration information. Interpretation: Drug outlets appear over-supplied in Vietnam compared to other countries. Unregistered outlets and outlets without degree-qualified pharmacists are prevalent, especially in poor and rural areas, posing a risk for inappropriate supply of antimicrobials, which may contribute to AMR, and raises questions of equitable healthcare access. Funding: This study was funded by a grant from the Australian Department of Foreign Affairs and Trade.
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Outage probability (OP) and potential throughput (PT) of multihop full-duplex (FD) nonorthogonal multiple access (NOMA) systems are addressed in the present paper. More precisely, two metrics are derived in the closed-form expressions under the impact of both imperfect successive interference cancellation (SIC) and imperfect self-interference cancellation. Moreover, to model short transmission distance from the transmit and receive antennae at relays, the near-field path-loss is taken into consideration. Additionally, the impact of the total transmit power on the performance of these metrics is rigorously derived. Furthermore, the mathematical framework of the baseline systems is provided too. Computer-based simulations via the Monte Carlo method are given to verify the accuracy of the proposed framework, confirm our findings, and highlight the benefits of the proposed systems compared with the baseline one.
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The objectives of this study were to describe the epidemiology of African swine fever (ASF) and to identify factors that increased commune-level risk for ASF in Can Tho, a province in the Mekong River Delta of Vietnam. In 2019, a total of 2377 of the 5220 pig farms in Can Tho were ASF positive, an incidence risk of 46 (95% CI 44-47) ASF positive farms for every 100 farms at risk. Throughout the outbreak ASF resulted in either the death or culling of 59,529 pigs out of a total population size of 124,516 (just under half of the total pig population, 48%). After the first detection in Can Tho in May 2019, ASF spread quickly across all districts with an estimated dissemination ratio (EDR) of greater than one up until the end of July 2019. A mixed-effects Poisson regression model was developed to identify risk factors for ASF. One hundred unit increases in the number of pigs per square kilometre was associated with a 1.28 (95% CrI 1.05-1.55) fold increase in commune-level ASF incidence rate. One unit increases in the number of pig farms per square kilometre was associated with a 0.91 (95% CrI 0.84-0.99) decrease in commune-level ASF incidence rate. Mapping spatially contiguous communes with elevated (unaccounted-for) ASF risk provide a means for generating hypotheses for continued disease transmission. We propose that the analyses described in this paper might be run on an ongoing basis during an outbreak and disease control efforts modified in light of the information provided.
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Vírus da Febre Suína Africana , Febre Suína Africana , Epidemias , Doenças dos Suínos , Suínos , Animais , Febre Suína Africana/prevenção & controle , Vietnã/epidemiologia , Surtos de Doenças/veterinária , Surtos de Doenças/prevenção & controle , Análise Espacial , Epidemias/veterinária , Sus scrofa , Doenças dos Suínos/epidemiologiaRESUMO
The objective of this study is to report the complete-genome sequence of a field African swine fever (ASF) virus (ASFV), namely ASF/VN/CanTho-OM/2021, which caused a fatal outbreak in domestic pigs in the Mekong Delta. Complete-genome sequencing detected an 18 bp nucleotide deletion in the EP402R gene (encoding for serotype-specific proteins CD2v) of ASF/VN/CanTho-OM/2021, which was determined to belong to genotype 2 and serotype 8. This mutation pattern was confirmed as unique in GenBank; thus, ASF/VN/CanTho-OM/2021 can be considered a novel variant, with a potential change of sero-characteristics within genotype 2. An additional unique mutation of 78 bp nucleotide insertion was also observed in the B475L gene. Additionally, four copies of tandem repeat sequences were found in the intergenic region (IGR) located between I73R and I329L, previously assigned as the IGR III variant. This study is the first to report the complete genome of ASFV in the Mekong Delta, and it highlights the necessity of strengthening molecular surveillance to provide further knowledge on the evolution and incursion of ASFV in the Mekong Delta and Vietnam.
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Multi-element analysis combined with chemometric method has been used to investigate the distinguish between Sengcu rice and other types of rice origins in Vietnam. In Sengcu rice, As, Ba Sr, Pb, Ca, Se were confirmed as the key elements for geographical traceability among three fields of Lao Cai, whereas Al, Ca, Fe, Mg, Ag, As were major factors to distinguish between Sengcu and other types of rice. Based on linear discriminant analysis and partial least squares-discriminant analysis model, overall correct identification rates distinguishing between Sengcu and other types of rice were approximately 100% in both training and validation test. Moreover, to distinguish geographical origin of Sengcu rice samples, these rates vary from 80% to 99%. These results suggest the presence of food adulteration illustrated in the latter.
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Oryza , Análise Discriminante , Contaminação de Alimentos , Geografia , Análise MultivariadaRESUMO
The impact of low pathogenicity avian influenza (LPAI) has been confirmed mainly in farms. Unlike apparent losses caused by the high pathogenicity avian influenza (HPAI), the LPAI impact has been hardly evaluated due to underestimating its spread and damage. In 2019, a questionnaire study was conducted in southern Vietnam to identify the specific risk factors of LPAI virus (LPAIV) circulation and to find associations between husbandry activities and LPAI prevalence. A multilevel regression analysis indicated that keeping Muscovy ducks during farming contributed to LPAIV positivity [Odds ratio=208.2 (95% confidence interval: 13.4-1.1 × 104)]. In cluster analysis, farmers willing to report avian influenza (AI) events and who agreed with the local AI control policy had a slightly lower risk for LPAIV infection although there was no significance in the correlation between farmer characteristics and LPAI occurrence. These findings indicated that keeping Muscovy ducks without appropriate countermeasures might increase the risk of LPAIV infection. Furthermore, specific control measures at the local level are effective for LPAIV circulation, and the improvement of knowledge about biosecurity and attitude contributes to reducing LPAI damage.
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Vírus da Influenza A , Influenza Aviária , Doenças das Aves Domésticas , Animais , Galinhas , Patos , Fazendas , Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Vietnã/epidemiologia , VirulênciaRESUMO
This paper comprehensively investigates the performance of the D2D underlaying cellular networks where D2D communications are operated concurrently with cellular networks provided that the aggregate interference measured on licensed users is strictly guaranteed. In particular, we derive the outage probability (OP), the average rate, and the amount of fading (AoF) of the D2D networks in closed-form expressions under three distinct power allocation schemes, i.e., the path-loss-based, equal, and random allocation schemes. It is noted that the considered networks take into consideration the impact of the intra-D2D networks, the inter-interference from the cellular networks and background noise, thus involving many random variables and leading to a complicated mathematical framework. Moreover, we also reveal the behavior of the OP with respect to the transmit power based on the rigorous mathematical frameworks rather than the computer-based simulation results. The derived framework shows that increasing the transmit power is beneficial for the OP of the D2D users. Regarding the cellular networks, the coverage probability (Pcov) of the cellular users is computed in closed-form expression too. Monte Carlo simulations are given to verify the accuracy of the proposed mathematical frameworks. Our findings illustrate that the power allocation method based on prior path-loss information outperforms the other methods in the average sum rate.
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Algoritmos , Redes de Comunicação de Computadores , Simulação por Computador , Método de Monte Carlo , ProbabilidadeRESUMO
The present work aimed to study the effect of ozonation on the organic sum parameters linked to enhanced biodegradability. Laboratory experiments were conducted with the effluent of four Austrian urban wastewater treatment plants with low food to microorganism ratios and different matrix characteristics. Biochemical oxygen demand over 5 days (BOD5) was measured before ozonation and after application of different specific ozone doses (Dspec) (0.4, 0.6 and 0.8 g O3/g DOC). Other investigated organic parameters comprised chemical oxygen demand (COD), dissolved organic carbon (DOC), UV absorption at 254 nm (UV254), which are parameters that are applied in routine wastewater analysis. Carbamazepine and benzotriazole were measured as reference micropollutants. The results showed a dose-dependent increase in biological activity after ozonation; this increase was linked to the enhanced biodegradability of substances that are recalcitrant to biodegradation in conventional activated sludge treatment. The highest relative change was determined for BOD5, which already occurred between 0 and 0.4 g O3/g DOC for all samples. Increasing the Dspec to 0.6 and 0.8 g O3/g DOC resulted in a less pronounced increase. DOC was not substantially decreased after ozonation, which was consistent with a low reported degree of mineralization, while partial oxidation led to a quantifiable decrease in COD (7 to 17%). Delta UV254 and the decline in specific UV absorption after ozonation clearly correlated with Dspec. In contrast, for COD and biodegradable DOC (BDOC), a clear dose-response pattern was identified only after exposure to BOD5 measurement. Indications for improved biodegradability were further supported by the rise in the BOD5/COD ratio. The results indicated that subsequent biological processes have a higher degradation potential after ozonation. The further reduction in biodegradable organic carbon emission by the combination of ozonation and biological post treatment represents another step towards sustainable water resource management in addition to micropollutant abatement.
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Ozônio , Poluentes Químicos da Água , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Oxirredução , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Poluentes Químicos da Água/análiseRESUMO
In South Vietnam, live bird markets (LBMs) are key in the value chain of poultry products and spread of avian influenza virus (AIV) although they may not be the sole determinant of AIV prevalence. For this reason, a risk analysis of AIV prevalence was conducted accounting for all value chain factors. A cross-sectional study of poultry flock managers and poultry on backyard farms, commercial (high biosecurity) farms, LBMs and poultry delivery stations (PDSs) in four districts of Vinh Long province was conducted between December 2016 and August 2017. A total of 3597 swab samples were collected from birds from 101 backyard farms, 50 commercial farms, 58 sellers in LBMs and 19 traders in PDSs. Swab samples were submitted for AIV isolation. At the same time a questionnaire was administered to flock managers asking them to provide details of their knowledge, attitude and practices related to avian influenza. Multiple correspondence analysis and a mixed-effects multivariable logistic regression model were developed to identify enterprise and flock manager characteristics that increased the risk of AIV positivity. A total of 274 birds were positive for AIV isolation, returning an estimated true prevalence of 7.6% [95% confidence interval (CI): 6.8%-8.5%]. The odds of a bird being AIV positive if it was from an LBM or PDS were 45 (95% CI: 3.4-590) and 25 (95% CI: 1.4-460), respectively, times higher to the odds of a bird from a commercial poultry farm being AIV positive. The odds of birds being AIV positive for respondents with a mixed (uncertain or inconsistent) level and a low level of knowledge about AI were 5.0 (95% CI: 0.20-130) and 3.5 (95% CI: 0.2-62), respectively, times higher to the odd of birds being positive for respondents with a good knowledge of AI. LBMs and PDSs should receive specific emphasis in AI control programs in Vietnam. Our findings provide evidence to support the hypothesis that incomplete respondent knowledge of AI and AIV spread mechanism were associated with an increased risk of AIV positivity. Delivery of education programs specifically designed for those in each enterprise will assist in this regard. The timing and frequency of delivery of education programs are likely to be important if the turnover of those working in LBMs and PDSs is high.
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Vírus da Influenza A , Influenza Aviária , Animais , Estudos Transversais , Influenza Aviária/epidemiologia , Aves Domésticas , Vietnã/epidemiologiaRESUMO
Avian pathogenic Escherichia coli (APEC) is the main causative agent of avian colibacillosis, which is an important systemic disease of profound economic and clinical consequences for the poultry industry worldwide. In this study, 975 E. coli strains were isolated from 2,169 samples collected from cloacal swabs of chickens, in-farm wild animals (ants, geckos, flies, and rats), and environment. The highest proportion of E. coli isolation was obtained from chicken cloacal swabs with 71.05% (95% confidence interval (CI) 66.69-75.05%) followed by the proportions of 38.15% (95% CI 35.41-40.97%) and 38.11% (95% CI 34.15-42.24%) from wild animals or environment, respectively. Distribution of O-antigen serotypes of the E. coli isolates, including O1, O2, O18, and O78, was determined by PCR. The most predominant serotype was O18 (10.56%) followed by O2 (9.44%), O1 (7.79%), and O78 (6.56%). Of note, serotype O18 was more likely distributed in the examined wild animals, especially in geckos. Polymorphic DNA fingerprints, generated by ERIC-PCR, of representative E. coli strains of each serotype revealed genetic heterogeneity of the examined E. coli, and O18 was more divergent with 63 clusters formed from 66 isolates. Furthermore, several E. coli strains from different sample sources shared high DNA fingerprint relatedness, suggesting that there exists complex transmission of E. coli from chickens to wild animals and environment and vice versa in poultry husbandry settings. Although pathotypes of the examined E. coli were not determined in this study, our results provided important findings of epidemiological and genetic characteristics of E. coli in the Mekong Delta and highlighted the prerequisite of stricter biocontainment to reduce the prevalence and consequences of APEC in poultry production.