Z-number based fuzzy MCDM models for analyzing non-traditional security threats to finance supply chains: A case study from Vietnam.

Non-traditional security (NTS) threats have a vast and profound impact on many aspects of economic, political, social, and many other areas, especially supply chain finance (SCF), particularly in countries like Vietnam, which potentially affects the economic efficiency of businesses' supply chain financial, thereby affecting the general economy of the country and the world. In order to prevent and minimize the negative impacts caused by NTS threats to SCF, this study was conducted to identify NTS threats affecting SCF in Vietnam, at the same time calculate the weight of the impact level and find out the cause and effect relationship between them. Solution strategies are also proposed and ranked, thereby serving as a reference basis for relevant parties to choose appropriate response solutions. Due to the multi-criteria nature of NTS threats, the multiple criteria decision-making (MCDM) method is used in combination with the Z-number concept and Fuzzy set theory to approach the problem of certainty and increase the accuracy of study. The NTS threats are first identified through a literature review and then validated for suitability using the DELPHI technique (DELPHI). Suitable threats will be determined by relationship, weighted by Decision Making Trial And Evaluation Laboratory (DEMATEL) method. Proposed strategies are ranked using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method. The results indicate that there are 19 NTS factors affecting SCF in Vietnam, and the global economic downturn, pandemic and health crisis, financial crisis and cybersecurity risk are the four root cause factors with the most decisive influence. Businesses and concerns need to prioritize addressing these four threats because they not only have a strong impact but also entail many other threats. The two strategies considered to be the most effective are a sustainable practice and a risk-hedging strategy. Businesses, governments, and stakeholders also should pay attention to the macroeconomic environment, technology, and environment and build sustainable businesses, regularly monitoring economic fluctuations and creating plans to prevent risks.

Molecular identification of sparganum of Spirometra mansoni isolated from the abdominal cavity of a domestic cat in Vietnam.

Cats normally play a role of the definitive host in which the plerocercoid (sparganum), the second larval form of Spirometra spp., develops into an adult in the intestines. However, some cases of cats with visceral or subcutaneous sparganosis were sporadically reported worldwide. We herein documented the discovery of a sparganum in abdominal cavity of a domestic cat during a surgery of dystocia. The larva was molecularly identified as Spirometra mansoni, belonging to Type I, that was recently misidentified to be S. erinaceieuropaei in several Asian countries. This is the first report for sparganum of S. mansoni in the cat. The future study is necessary to provide further insights into the species of Spirometra causing sparganosis and spirometrosis in humans and other animals.

Synthesis of MAPbBr3 -Polymer Composite Films by Photolysis of DMF: Toward Transparent and Flexible Optical Physical Unclonable Functions (PUFs) with Hierarchical Multilevel Complexity.

Physical entities with inherent randomness have been investigated as anti-counterfeiting labels based on physical unclonable functions (PUFs). Herein, a transparent and flexible optical PUF label associated with multilevel complexity is demonstrated by taking advantage of the optical properties of hierarchical morphologies of the composite film composed of metal halide perovskite nanoparticles (MAPbBr3 NPs) and the intrinsic spinodal-decomposition-like phase separation of polymer blend (PMMA/PS blend). Due to the combinatorial effects of the photolysis synthesis of MAPbBr3 and the thermodynamic instability of the PMMA/PS blend, randomized patterns emerge at two-level scales. These patterns are intrinsically non-deterministic, and therefore, the PUF labels from the multilevel random patterns are challenging to replicate. This is mainly attributed to random spot patterns (higher-level patterns) confined within intricate bicontinuous patterns (lower-level patterns).

Association of envelope-specific B-cell differentiation and viral selective pressure signatures in HIV-1 CRF01_AE infection.

OBJECTIVE: In HIV type 1 (HIV-1) infection, virus-specific B-cell and neutralizing antibody (NAb) responses are impaired but exert selective pressure on target viral Envelope (Env) resulting in prominent sequence diversification among geographical areas. The basal induction patterns of HIV Env-specific B cells and their interaction with HIV Env awaits clarification. DESIGN: We investigated the relationship of Env polymorphisms and Env-specific B-cell responses in treatment-naive HIV-1 CRF01_AE-infected Vietnamese. METHODS: Samples of 43 HIV-1 CRF01_AE infection-identified individuals were divided into acute-phase ( n  = 12) and chronic-phase ( n  = 31) by combined criteria of serological recent-infection assay and clinical parameters. We quantified subcloning-based polymorphic residue site numbers in plasma-derived Env variable region 1-5 (V1-V5)-coding regions within each individual, designating their summation within each region as variant index. Peripheral blood Env gp 140-specific B-cell responses and plasma neutralizing activity of Env pseudoviruses were examined to analyze their relationship with variant index. RESULTS: HIV-1 CRF01_AE Env gp140-specific total B-cell and plasma cell (CD19 + IgD - CD27 + CD38 + CD138 + ) responses were determined. In chronic-phase samples, significant correlation of variant index in all Env V1-V5 regions with Env-specific plasma cell responses was shown, and V1-V5 total variant index correlated stronger with Env-specific plasma cell as compared with total Env-specific B-cell responses. Env V5 variant index was significantly higher in chronic-phase cross-neutralizers of V5-polymorphic/VRC01-insensitive CRF01_AE Env. CONCLUSION: Results revealed the association between circulating Env-specific plasma cell responses and Env polymorphisms, implicating selective pressure on Env by plasma cell-derived antibodies and conversely suggests that Env-specific B-cell induction alone is insufficient for exerting Env selective pressure in HIV infection.

Pressure-induced fluorescence enhancement of FAαPbBr2+α composite perovskites.

FAαPbBr2+α composite perovskites consisting of 0D FA4PbBr6 and 3D FAPbBr3 have been synthesized by a solid state reaction. Due to the endotaxy passivation of FAPbBr3 by FA4PbBr6, FAPbBr3 crystals were stably deformed without agglomeration from the cubic to the orthorhombic structure by compression, which led to a significant PL enhancement.

Perovskite Nanoparticle Composite Films by Size Exclusion Lithography.

Perovskite nanoparticle composite films with capability of high-resolution patterning (≥2 µm) and excellent resistance to various aqueous and organic solvents are prepared by in situ photosynthesis of acrylate polymers and formamidinium lead halide (FAPbX3 ) nanoparticles. Both positive- and negative-tone patterns of FAPbX3 nanoparticles are created by controlling the size exclusive flow of nanoparticles in polymer networks. The position of nanoparticles is spatially controlled in both lateral and vertical directions. The composite films show high photoluminescence quantum yield (up to 44%) and broad color tunability in visible region (λpeak = 465-630 nm).

An Alarmingly High Proportion of HIV-1 Isolates Carrying Mutations Corresponding to Resistance to Antiretroviral Drugs among HIV-Positive High-Risk Groups in Central Vietnam: a Substudy of the National Sentinel Survey.

We studied the prevalence of HIV drug resistance among high-risk groups such as injecting drug users (IDUs), female sex workers (FSWs), and men having sex with men (MSM) in central Vietnam. We used HIV-positive blood samples from 2012-2013 sentinel surveillance surveys. Study subjects were screened for HIV infection by standardized screening assays, and the HIV-positive samples were further tested for HIV viral load and drug-resistance mutations (DRMs) by in-house assays. DRMs were identified using the Stanford University online sequence analysis tool. Their risk behaviors were also investigated. During the study period, 6,016 (high-risk) subjects were screened, and 97 tested positive for HIV infection (IDUs: n = 63, 3.0%; FSWs: n = 24, 0.9%; and MSM: n = 10, 1.0%). Ninety-two of the 97 samples (45 from 2012 and 47 from 2013) were available for further testing. HIV RNA was detected in 56 (60.9%) of the 92 samples, and drug resistance genotyping was successfully performed on 40 (71.4%) samples. All these isolates were subtype CRF01_AE, except for 1 (2.5%) IDU whose HIV belongs to subtype B. Thirteen individuals (32.5%) were carrying HIV with at least 1 DRM: 9 IDUs, 1 FSW, and 3 MSM. Thus, HIV seroprevalence among high-risk individuals in central Vietnam is low, but a high proportion of drug resistant HIV-1 isolates is observed in the high-risk group.

High proportion of HIV serodiscordance among HIV-affected married couples in northern Vietnam.

INTRODUCTION: Little is known about the state of HIV transmission among married couples in Vietnam. This study aims to clarify HIV serostatus in this group and elucidate risk factors for intra-marital HIV transmission. METHODS: In 2012, we enrolled a group of HIV-positive married men registered at the HIV outpatient clinic of a referral hospital in northern Vietnam, along with their wives. Sociodemographic, behavioural and clinical data were collected from men and wives. HIV serodiscordant couples were followed until March 2014 to determine seroconversion rate. A phylogenetic analysis was performed based on env V3 sequence to detail cluster formation among men. RESULTS: Of the 163 HIV-positive men enrolled in the study, 101 (62.0%) had wives testing HIV-negative. Half of men reported injecting drug use (IDU) as a likely transmission route. Couples reported a high incidence of unprotected sexual intercourse prior to diagnosis; the median (inter quartile range) was 4 (4-8) times per month. Only 17 couples (10.4%) reported using condoms during at least half these instances. Multivariable analysis revealed IDU history among men was independently associated with HIV-negative wives (adjusted OR 0.31; 95% CI 0.10-0.95, p=0.041). Phylogenetic analysis of 80 samples indicated CRF01_AE. Of these, 69 (86.3%) clustered with IDU-associated viruses from Vietnam. No HIV seroconversion was identified during a follow-up of 61 serodiscordant couples, with 126.5 person-years of observation during which HIV-infected men were on antiretroviral drug therapy (ART). CONCLUSION: High HIV serodiscordance was observed among HIV-affected married couples in northern Vietnam. A large number of at-risk wives therefore remain HIV-negative and can be protected with measures including proper use of ART if couples are made aware of the serodiscordance through screening.

Reinfection of dogs with fish-borne zoonotic trematodes in northern Vietnam following a single treatment with praziquantel.

BACKGROUND: Fish-borne zoonotic trematodes (FZT) infections including liver- and minute intestinal flukes are common in Southeast Asia in both humans and domestic animals eating raw fish and since 2010, the liver flukes are recognised as neglected tropical diseases by WHO. Mass drug treatment with praziquantel is advised for humans, but no recommendations for control of the FZT in the reservoir hosts exist. METHODOLOGY/PRINCIPAL FINDINGS: A study was conducted to assess the ability of praziquantel treatment for control of FZT in farm dogs in an endemic area in Northern Vietnam. Initially, 101 dogs from 73 households were examined for small trematode eggs in their faeces. Forty seven copro-positive dogs were included in the study. Thirty eight dogs received treatment with a single dose of 40 mg/kg of praziquantel. A group of nine dogs were left untreated. Coprological examination for small trematode eggs was performed on day 0, 3, 10, 30, 60, 90 and 120 post treatment. Farmers were questioned about dog keeping practises. All dogs were copro-negative for small trematode eggs on both day 3 and 10 post treatment. From day 30 onwards previously negative dogs became positive again. The reinfection rates were 26.3% (day 30), 45.5% (day 60), 53.1% (day 90), 61.3% (day 120).The nine untreated dogs remained positive throughout the study period. There was no difference in the intensity of infection at day 0 and 120 neither in the treated or untreated group. CONCLUSION: Dogs had easy access to raw fish and did not receive treatment against flukes by their owner. More than 50% of the dogs were reinfected 3 months post treatment. We do not recommend controlling FZT infections in dogs by anthelmintic treatment alone since reinfection occurs fast under the existing farm management systems.

Experimental infection with the small intestinal trematode, Haplorchis pumilio, in young dogs.

Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on the role of domestic animals in the transmission of FZT in Northern Vietnam found that dogs, mainly infected with Haplorchis pumilio, contributed widely to the transmission of FZT. On this background, we conducted an experimental infection with H. pumilio to elucidate population dynamics and host reactions in dogs. Eight household-reared dogs (3-6 months old), were each orally infected with 500 H. pumilio metacercariae obtained by artificial digestion of naturally infected fish. Another eight dogs were included as uninfected controls. Faecal examination for eggs was performed twice weekly using a sieving and sedimentation technique. Body temperature and weight of the dogs were measured as was total white blood cells, blood eosinophils and packed cell volume. Subsets of dogs were examined post-mortem for presence of adult FZT at three different time points post infection by sectioning of the small intestine and caecum into four parts. Patent infections established in all eight infected dogs. The worm establishment ranged from 15 to 121 flukes (3-24%, mean 12%). Faecal egg excretion was measured in all eight infected dogs but no more than two eggs per g faeces (epg) were found at any time. Infections lasted for at least two months as documented by the presence of adult flukes in all three dogs necropsied on day 58 post infection. The predilection site of the flukes was identified as the lower part of jejunum (93% of total worm burden). The results of the haematological tests did not differ between the infected and uninfected group. Further, no clinical symptoms were observed in the infected group and no macroscopic pathological changes could be assigned to the trematode infections, neither did histopathological examination of the intestine reveal any differences between the infected and the control dogs. This study provides the first basic knowledge on the establishment, duration and location of H. pumilio infection in dogs. However, before any control measures can be recommended, knowledge regarding infection dynamics, epidemiology, health impact and control is needed.

Evaluation of the role of rats as reservoir hosts for fishborne zoonotic trematodes in two endemic northern Vietnam fish farms.

Fishborne zoonotic trematodes (FZTs) pose a food safety risk for the aquaculture industry in Vietnam. The risk of being infected from eating raw fish applies not only to humans but also to domestic animals which can serve as reservoir hosts in fish farms. The role of rodents, commonly found in fish farms, as reservoir hosts has not been adequately evaluated. To study this question, commensal and rice field rats were collected from fish farms in Nghia Lac and Nghia Phu communes, Nam Dinh province, Vietnam and examined for FZT infection. A total of 250 rats (Rattus norvegicus, Rattus argentiventer, and Bandicota indica) were collected and examined; the rats were trapped in the farm households (commensal) and in rice fields adjoining the fish ponds (field). The total prevalence of all parasites was 52.8 %: nematodes, 42.4 %; trematodes 18.0 %; and cestodes, (3.6 %), including two zoonotic cestode species, Raillietina celebenisis and Hymenolepis diminuta. Although overall prevalence and intensity of parasite infection did not differ significantly among rat species or between the two communes, the intensity of nematode infection was significantly higher in commensal rats (p < 0.05). The only FZTs recovered were the intestinal flukes Echinostoma cinetorchis and Centrocestus formosanus, both at low prevalence. Because the most common FZTs found in fish from these communes are Haplorchis pumilio and Haplorchis taichui, neither of which were found in the rats, we conclude that rats are not significant reservoir hosts for FZT in these Vietnamese fish farms.