Enrofloxacin (ENR) has been widely used to treat bacterial infections in catfish aquaculture. However, little is known about the elimination of ENR in fish following treatment in aquaculture ponds. ...The aim of this study was through on-farm trials to establish the withdrawal period for ENR following treatment of striped catfish (Pangasianodon hypophthalmus).
Three catfish ponds were treated daily for five consecutive days with medicated pelleted feed containing ENR (10mg/kg body weight) following normal farmer procedures. Sampling of catfish muscle/skin for residue analysis was done one day before the first feeding with medicated feed as well as three times during and five times after (7, 15, 30, 45, and 200days) application of medicated feed. ENR and its metabolite ciprofloxacin (CIP) residues were analyzed by Liquid Chromatography coupled to Mass Spectrometry (LC-MS/MS).
As expected, ENR and CIP residues initially accumulated in mixed muscle/skin and the concentrations were subsequently reduced during the sampling period. After 45days (D45), the concentration of total ENR and CIP was 30.8±4.1μg/kg. Our results show that a withdrawal time of 45days is sufficient for striped catfish treated with ENR, i.e. below the Maximum Residue Limit (MRL) assigned by the Commission of the European Communities (100μg/kg) in fish for human consumption but above the action level proposed by the US Food and Drug Administration (FDA) (5μg/kg). Further, the 30-days withdraw period declared on the ENR products sold to catfish farmers is inadequate. The ENR and CIP residues found in skin about 200days after treatment warrants follow-up studies, e.g. of possible food safety risks.
•An on-farm trial with striped catfish in Vietnam to establish the withdrawal period for enrofloxacin showed that 45days after treatment fish muscle contained a total of 30.8±4.1μg/kg ENR and CIP.•A withdraw time of 45days meets the Maximum Residue Limit (MRL) assigned by the Commission of the European Communities (100μg/kg) in fish for human consumption, but is above the action level proposed by the Food and Drug Administration (FDA) (5μg/kg) in the United States.•The 30-days withdraw period declared by the manufacturers of ENR products sold to catfish farmers is inadequate.•At harvest, skin samples still contained high levels of ENR and CIP metabolites which may constitute a food safety risk when catfish skin-derivate products are sold for human consumption.
Semi-automated patient transfer devices are essential in health facilities. Especially for patients with limited mobility. Improper patient transfer or poorly designed transfer equipment will cause ...unnecessary injury to both the patient and the medical staff. In this paper, we choose to solve the problem of working conditions of one of the current patient transfer devices with the aim of ensuring the safety of the device. Three problems are posed including: Center of gravity distribution to avoid overturning - Simulation of natural frequencies - Durability for critical locations. The results show that the structure of the product ensures safe working conditions for users.
Information on the relationship between rainfall intensity, duration and accumulation frequency or return period (IDF) is commonly utilized in the design and management of urban drainage systems. Can ...Tho City, located in the Vietnamese Mekong Delta, is a city which has recently invested heavily in upgrading its stormwater drainage systems in the hope of preventing reoccurring flood events. Yet, much of these works were designed based on obsolete and outdated IDF rainfall curves. This paper presents an updated IDF curve for design rainfall for Can Tho City. For each duration and designated return period, a cumulative distribution function (CDF) was developed using the Pearson III, Log-Pearson III, and Log-Normal distribution functions. In order to choose the best IDF rainfall curve for Can Tho City, the CDF rainfall curve and empirical formulas used in Vietnam and Asia (Vietnamese standard 7957:2008, Department of Hydrology, Ministry of Transportation, Talbot, Kimijima, and Bermard) were compared. The goodness of fit between the IDF relationship generated by the frequency analysis (CDF curve), and that predicted by the IDF empirical formulas was assessed using the efficiency index (EI), and the root mean squared error (RMSE). The IDF built from Vietnam’s standard TCVN 7957:2008 with new parameters (A = 9594, C = 0.5, b = 26, n = 0.96) showed the best performance, with the highest values of EI (0.84 ≤EI≤ 0.93) and the lowest values of RMSE (2.5 ≤RMSE≤ 3.2), when compared to the other remnants.
Using cloud services from mobile devices has become a growing trend because of its mobility and convenience. However, mobile devices join and leave cloud services more frequently than traditional ...computers, which causes energy inefficiency in a cloud data center. Waste, in the form of energy and cooling requirements, particularly occurs when a mobile device disconnects from a service, but the cloud servers, known as virtual machines (VMs), continue running. The VMs should transition to lower-power states instead remaining active. However, transition to a lower-power state causes a service delay when users reconnect to the service because VMs in a lower-power state are not ready to serve. Therefore, an efficient energy policy must not only maximize energy savings but also minimize service delays. In this paper, we propose two approaches to energy efficiency: an Instant Energy Policy (IEP) that can quickly find an appropriate low-power state based on a predicted disconnection time and a Prediction-based Energy Policy (PrEP) that determines when to transition VMs to a low-power state and when to return them to the active state based on each users activity history. IEP predicts the unknown disconnection time using the multisize sliding windows workload estimation technique, which supports a non-stationary environment. This method can quickly obtain an energy policy, but it is limited when disconnection time fluctuates widely. PrEP presents an improved approach to achieve an optimal global result with respect to both energy consumption and service delay. Through simulations with a real-world dataset collected by the MIT Human Dynamics Lab, we show that PrEP provides approximately 20% power saving over the benchmark policies while guaranteeing minimal service delay.
In this study, selenium microparticles (SeMPs) were green-synthesized by utilizing the Terminalia catappa leaves extract as an effective reducing agent. SeMPs were then decorated onto graphene oxide ...(GO) with the assistance of ultrasound using the ex-situ technique to obtain the SeMPs-GO composite. SeMPs and SeMPs-GO were thoroughly characterized with modern analytical methods, whereas the antibacterial performance of the composites was evaluated via the optical density method. Particularly, SeMPs-GO held up an inhibition of 99 % against both Gram-positive and Gram-negative bacteria strains as well as restrained 50 % of fungal activity. SeMPs-GO was additionally incorporated onto chitosan (CTS) to collect the SeMPs-GO/CTS membrane which was characterized by similar advanced analysis methods. The antibacterial property of the membrane was determined by the inhibition zone diameter. Furthermore, the membrane exhibited good thermal and mechanical characteristics, showing no sign of degradation at a temperature below 260 °C, and a tensile strength of 38 N/mm2. The swelling degree reached 148 % after 6 h of immersion in water, which was stable after 72 h (153 %). The obtained membrane can potentially be utilized for medical and food applications.
We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was ...confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions.
The SPOT-MAS assay "Screening for the Presence Of Tumor by Methylation And Size" detects the five most common cancers in Vietnam by evaluating circulating tumor DNA in the blood. Here, we validated ...its performance in a prospective multi-center clinical trial, K-DETEK. Our analysis of 2795 participants from 14 sites across Vietnam demonstrates its ability to detect cancers in asymptomatic individuals with a positive predictive value of 60%, with 83.3% accuracy in detecting tumor location. We present a case report to support further using SPOT-MAS as a complementary method to achieve early cancer detection and provide the opportunity for early treatment.
Climate and rainfall are extremely non-linear and complicated phenomena, which require numerical modelling to simulate for accurate prediction. We obtained local historical rainfall data for 12 ...meteorological stations in the Vietnamese Mekong Delta (VMD) for the 45-year period 1978–2022, to predict annual rainfall trends. A statistical time series predicting technique was used based on the autoregressive integrated moving average (ARIMA) model. We utilized the seasonal ARIMA process of the form (p,1,q)(P,1,Q) for our study area. The best seasonal autoregressive integrated moving average (SARIMA) models were then selected based on the autocorrelation function (ACF) and partial autocorrelation function (PACF), the minimum values of Akaike Information Criterion (AIC) and the Schwarz Bayesian Information (SBC). The seasonal autoregressive integrated moving average model with external regressors (SARIMAX) was discovered, and a series of SARIMA models of various orders were estimated and diagnosed. To evaluate model fitting, we used the Nash–Sutcliffe coefficient (Nash) and the root-mean-square error (RMSE). The study has shown that the SARIMA (1, 1, 1)(2, 1, 1)
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and SARIMA (1, 1, 1)(2, 1, 1)
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model were appropriate for analyzing and forecasting future rainfall patterns at particular meteorological station in the VMD. The results showed the SARIMA model is more reliable and provides more accurate projections than other commonly used statistical methods, notably interval forecasts. We found that interpretable and reliable near-term location-specific rainfall predicts can be provided by the SARIMA-based statistical predicting model.
In remote display protocols, screen image compression plays an important role to improve quality of experience (QoE) of users and reduce the bandwidth consumption. Not all image elements on the ...display have the same type, so it is wise to apply a screen image classification for compression decision. In this paper, we propose a novel efficient approach for screen image classification that separate the captured screen into 2 types of blocks: text and non-text block. Our method is a 2-stage process that is different from other works because of the appearance of text localization in the screen image as the first stage. This text localization is mainly based on edge feature and morphological operation in which we experiment with many kinds of edge detection methods. Then block-based classification categorizes the screen image blocks based on the positions of the detected text regions. The experimental results of high accuracy rate and low time consumption state our method is efficient in remote display protocol.
