Flat Seeking Bayesian Neural Networks

Bayesian Neural Networks (BNNs) provide a probabilistic interpretation for deep learning models by imposing a prior distribution over model parameters and inferring a posterior distribution based on observed data. The model sampled from the posterior distribution can be used for providing ensemble predictions and quantifying prediction uncertainty. It is well-known that deep learning models with lower sharpness have better generalization ability. However, existing posterior inferences are not aware of sharpness/flatness in terms of formulation, possibly leading to high sharpness for the models sampled from them. In this paper, we develop theories, the Bayesian setting, and the variational inference approach for the sharpness-aware posterior. Specifically, the models sampled from our sharpness-aware posterior, and the optimal approximate posterior estimating this sharpness-aware posterior, have better flatness, hence possibly possessing higher generalization ability. We conduct experiments by leveraging the sharpness-aware posterior with state-of-the-art Bayesian Neural Networks, showing that the flat-seeking counterparts outperform their baselines in all metrics of interest.Comment: Accepted at NeurIPS 202

TECHNICAL ASSESSMENT OF GAMMA-AMINO BUTYRIC ACID (GABA) PRODUCTION FROM RICE BRAN

This research focused on technical assessment of GABA production from rice bran through fermentation by Lactobacillus brevis. Influence of operating pressure on separation of GABA by nanofiltration membrane was investigated and 4 bar was suitable for the nanofiltration process. The purification of GABA by nanofiltration with constant feed volume was carried out and purity of GABA reached 4.8 folds, compared to feed, at 5 volumes of added water. At 40 of concentration factor in concentration of GABA solution by nanofiltration with full recycle of retentate, content of GABA reached 49.8 g/L. The production of GABA from defatted rice bran at pilot scale was carried out at 1,000 L/batch (equal to 200 kg of rice bran) of fermentation. Estimation of mass balance showed that, with 200 kg of defatted rice bran, 7.0 kg of GABA powder was obtained. Results indicated that, it is potential to produce GABA from rice bran through the fermentation by Lactobacillus brevis

Optimizing the ratios of standardized ileal digestible (SID) methionine plus SID cystine and SID threonine to SID lysine in low-protein diets for working boars

This study aimed to optimize the ratios of standardized ileal digestible (SID) methionine (Met) plus cystine (Cys), and threonine (Thr) to SID lysine (Lys) in low-protein diets for working boars. Forty-eight working Duroc boars were randomly allocated to one of 12 dietary treatments in a 3x4 factorial experimental design in which factor 1 was the ratios of SID Met plus Cys to SID Lys (50, 60, 70%), factor 2 was the ratios of SID Thr to SID Lys (40, 50, 60, 70%). Semen was collected at a 4 days interval for 6 weeks for 10 ejaculates. Semen volume (V), percentage of sperm with progressive motility (A), sperm concentration (C), and the total number of motile sperm per ejaculate (VAC) were measured. The results of the study revealed that the ratios of SID Met plus Cys to SID Lys in the diets affected the C and VAC. Values of C and VAC were highest at the ratios of SID Met plus Cys to SID Lys of 70% and lowest at 50% (P<0.05). Similarly, the ratios of SID Thr to SID Lys affected the C and VAC. Further, the values of C and VAC were highest at the ratio of SID Thr to SID Lys of 60% and lowest at 40% (P<0.05). There was no interaction effect between the two factors. In conclusion, the ratios of SID Met plus Cys to SID Lys of 70% and SID Thr to SID Lys of 60% in a 13.5% CP diet are optimal for working boars

A Multi-Center Randomised Controlled Trial of Gatifloxacin versus Azithromycin for the Treatment of Uncomplicated Typhoid Fever in Children and Adults in Vietnam

BACKGROUND: Drug resistant typhoid fever is a major clinical problem globally. Many of the first line antibiotics, including the older generation fluoroquinolones, ciprofloxacin and ofloxacin, are failing. OBJECTIVES: We performed a randomised controlled trial to compare the efficacy and safety of gatifloxacin (10 mg/kg/day) versus azithromycin (20 mg/kg/day) as a once daily oral dose for 7 days for the treatment of uncomplicated typhoid fever in children and adults in Vietnam. METHODS: An open-label multi-centre randomised trial with pre-specified per protocol analysis and intention to treat analysis was conducted. The primary outcome was fever clearance time, the secondary outcome was overall treatment failure (clinical or microbiological failure, development of typhoid fever-related complications, relapse or faecal carriage of S. typhi). PRINCIPAL FINDINGS: We enrolled 358 children and adults with suspected typhoid fever. There was no death in the study. 287 patients had blood culture confirmed typhoid fever, 145 patients received gatifloxacin and 142 patients received azithromycin. The median FCT was 106 hours in both treatment arms (95% Confidence Interval [CI]; 94-118 hours for gatifloxacin versus 88-112 hours for azithromycin), (logrank test p = 0.984, HR [95% CI] = 1.0 [0.80-1.26]). Overall treatment failure occurred in 13/145 (9%) patients in the gatifloxacin group and 13/140 (9.3%) patients in the azithromycin group, (logrank test p = 0.854, HR [95% CI] = 0.93 [0.43-2.0]). 96% (254/263) of the Salmonella enterica serovar Typhi isolates were resistant to nalidixic acid and 58% (153/263) were multidrug resistant. CONCLUSIONS: Both antibiotics showed an excellent efficacy and safety profile. Both gatifloxacin and azithromycin can be recommended for the treatment of typhoid fever particularly in regions with high rates of multidrug and nalidixic acid resistance. The cost of a 7-day treatment course of gatifloxacin is approximately one third of the cost of azithromycin in Vietnam. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN67946944

Numerical Computation of Hydrodynamic Characteristics of an Automated Hand-Washing System

The aim of this study is to develop a physical model and investigate the bactericidal effect of an automated hand-washing system through numerical computation, which is essential in areas affected by COVID-19 to ensure safety and limit the spread of the pandemic. The computational fluid dynamics approach is used to study the movement of the solution inside the hand-washing chamber. The finite element method with the k-ε model is applied to solve the incompressible Navier–Stokes equations. The numerical results provide insights into the solution’s hydrodynamic values, streamlines, and density in the two cases of with a hand and without a hand. The pressure and mean velocity of the fluid in the hand-washing chamber increases when the inlet flow rates increase. When the hand-washing chamber operates, it creates whirlpools around the hands, which remove bacteria. In addition, the liquid inlet flow affects the pressure in the hand-washing chamber. The ability to predict the hydraulic and cleaning performance efficiencies of the hand-washing chamber is crucial for evaluating its operability and improving its design in the future

Class Similarity Weighted Knowledge Distillation for Continual Semantic Segmentation

Deep learning models are known to suffer from the problem of catastrophic forgetting when they incrementally learn new classes. Continual learning for semantic segmentation (CSS) is an emerging field in computer vision. We identify a problem in CSS: A model tends to be confused between old and new classes that are visually similar, which makes it forget the old ones. To address this gap, we propose REMINDER - a new CSS framework and a novel class similarity knowledge distillation (CSW-KD) method. Our CSW-KD method distills the knowledge of a previous model on old classes that are similar to the new one. This provides two main benefits: (i) selectively revising old classes that are more likely to be forgotten, and (ii) better learning new classes by relating them with the previously seen classes. Extensive experiments on Pascal-Voc 2012 and ADE20k datasets show that our approach outperforms state-of-the-art methods on standard CSS settings by up to 7.07% and 8.49%, respectively

Class similarity weighted knowledge distillation for continual semantic segmentation

Deep learning models are known to suffer from the problem of catastrophic forgetting when they incrementally learn new classes. Continual learning for semantic segmentation (CSS) is an emerging field in computer vision. We identify a problem in CSS: A model tends to be confused between old and new classes that are visually similar, which makes it forget the old ones. To address this gap, we propose REMINDER - a new CSS framework and a novel class similarity knowledge distillation (CSW-KD) method. Our CSW-KD method distills the knowledge of a previous model on old classes that are similar to the new one. This provides two main benefits: (i) selectively revising old classes that are more likely to be forgotten, and (ii) better learning new classes by relating them with the previously seen classes. Extensive experiments on Pascal-VOC 2012 and ADE20k datasets show that our approach outperforms state-of-the-art methods on standard CSS settings by up to 7.07% and 8.49%, respectively

TẠO DÒNG VÀ BIỂU HIỆN GEN MÃ HÓA PROTEIN p65 TỪ MYCOPLASMA HYOPNEUMONIAE GÂY BỆNH SUYỄN LỢN TRONG VI KHUẨN ESCHERICHIA COLI BL21 (DE3)

In this study, we successfullycloned and expressed the p65 gene encoding for p65 proteinof Mycoplasma hyopneumonia (M. hyopneumonia) isolated from pig lungs collected in Thua Thien Hue province, Vietnam. The p65 gene was amplified and cloned into pET200/D-TOPO vector and then transformed into the E. coli BL21 (DE3) strain. The results showed that the p65 gene segment was 936 bp, identical to the published p65 gene on GenBank (accession number: CP003131.1), encoding a polypeptide chain of 311 amino acid residues, identical to anamino acid sequence of a protein on GenBank (accession number: AAB67173.1). The denatured SDS-PAGE analysis showed a protein band of 37 kDa which corresponded to 6×His-p65 fusion protein.Trong nghiên cứu này, chúng tôi đã tạo dòng và biểu hiện thành công gen p65mã hóa protein p65 của Mycoplasma hyopneumonia (M. hyopneumonia) được phân lập từ các mẫu phổi lợn ở Thừa Thiên Huế. Đoạn gen p65 được khuếch đại và gắn vào vector pET 200/D-TOPO và sau đó biến nạp vào chủng Echerichia coli BL21 (DE3). Kết quả cho thấy rằng gen p65 có kích thước khoảng 936 bp, mức tương đồng với trình tự gen được công bố trên GenBank (mã số: CP003131.1) là 100%, mã hóa chuỗi polypeptide dài 311 axitamin và có tương đồng với chuỗi polypeptide được công bố trên GenBank (mã số: AAB67173.1) là 100%. Phân tích điện di SDS-PAGE trong điều kiện biến tính cho thấy protein dung hợp 6xHis-p65 có khối lượng phân tử khoảng 37 kDa

Particulate air pollution in Ho Chi Minh city and risk of hospital admission for acute lower respiratory infection (ALRI) among young children

This study demonstrates that high level of PM increased the risk of admission for acute lower respiratory infection among Vietnamese children, especially for acute bronchiolitis and among males.High levels of air pollutants in Vietnam, especially particulate matters including PM, can be important risk factors for respiratory diseases among children of the country. However, few studies on the effects of ambient air pollution on human health have been conducted in Vietnam so far. The aim of this study is to examine the association between PM and hospital admission due to acute lower respiratory infection (ALRI) among children aged < 5 years old in Ho Chi Minh city, the largest city of Vietnam. Data relating PM and hospital admission were collected from February 2016–December 2017 and a time series regression analysis was performed to examine the relationship between PM and hospital admission including the delayed effect up to three days prior to the admission. We found that each 10 μg/m increase in PM was associated with an increase of 3.51 (95%CI: 0.96–6.12) risk of ALRI admission among children. According to the analysis, male children are more sensitive to exposure to PM than females, while children exposed to PM are more likely to be infected with acute bronchiolitis than with pneumonia. The study demonstrated that young children in HCMC are at increased risk of ALRI admissions due to the high level of PM concentration in the city's ambient air

High active and coke-resistant CeNiO3-based catalyst for methane bi-reforming

In this study, Ce1-xLaxNiO3 catalysts (x = 0.2, 0.4, 0.6, and 0.8) and Ce1-xLaxNiO3 on porous silica were prepared by co-precipitation. The effect of the La content on the catalytic activity in methane bi-reforming was investigated in the temperature range of 550 °C-750 °C. The physicochemical properties of the prepared catalysts were analysed by several methods, including X-ray diffraction, hydrogen temperature-programmed reduction, CO2 temperature-programmed desorption, N2 adsorption isotherm, energy-dispersive X-ray spectroscopy, Raman spectroscopy, scanning electron microscopy and high-resolution transmission electron microscopy. From the research results, the suitable substitution rate of La in Ce1-xLaxNiO3 was found to be x = 0.4; its conversions of CH4 of 94% and CO2 of 92% were achieved at 700 °C and GHSV 30000 mL/(g.h). However, the intense coke accumulation on Ce0.6La0.4NiO3 limited its development. The porous silica carrier improved the structure and properties of the Ce0.6La0.4NiO3 catalyst. The SiO2-supported catalyst (Ce0.6La0.4NiO3/SiO2) showed excellent stability and coke resistance, which had stable activity for 100 h of time on stream, structure stability and low coke accumulation; 2.37 mgC/gcat formed after 100 h (coke formation rate of 0.02 mmolC/(gcat.h)), which demonstrated that it was one of the best coke-resistant perovskite catalysts for the BRM reaction. The large surface area of silica and strong interaction of Ni with metal oxide reduced the metal Ni particle size to the threshold size (2−4 nm), where the strongly reduced coke accumulation, high basicity, and vacancy oxygen content of CeO2 and La2O3 were considered major contributors to the high activity and exceptional coke resistance. The high structural stability, anti-sintering performance and high coke resistance all contributed to the excellent durability of the Ce0.6La0.4NiO3/SiO2 catalyst. This work provides a new resolution for the development of coke-resistant perovskite catalysts for methane reforming