Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 122
Filtrar
Más filtros

Base de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-39177492

RESUMEN

In this study, pigs from 3 supply chains were slaughtered in an Australian summer and winter (n = 20 for each supply chain). The pigs were from 2 sexes (female and castrated male) and 2 carcass weight groups (high: 95.0 to 100.0 kg and low: 75.0 to 80.0 kg). From each carcass, the Biceps femoris (BF), Longissimus thoracis et lumborum (LTL), and Triceps brachii (TB) were excised at 24 h postmortem, vacuum packed, frozen at 24-48 h and transported to the lab. Cooking loss, Warner-Bratzler shear force (WBSF) and texture profile analysis (adhesiveness, chewiness, cohesiveness, hardness, resilience, and springiness) were measured in LTL and BF. pH, collagen content, and solubility and intramuscular fat (IMF) content were determined for all muscles. Results showed that BF was tougher than LTL, and winter samples were tougher than summer ones (P < 0.05). The TB had higher pH, collagen, and IMF content than BF and LTL (P < 0.05). Collagen solubility was higher in castrated male and winter samples. pH, collagen solubility, and IMF content were significantly (P < 0.05) related to chewiness and hardness in pork BF and LTL. pH and IMF were also related to cooking loss, while collagen solubility and IMF were related to WBSF (P < 0.05). The relationships of pH and IMF with pork texture were predominantly driven by the LTL, while the relationships between collagen solubility and texture were predominantly driven by the BF. Collagen solubility and IMF of pork BF and TB were related to those of LTL, but the correlations were not strong enough for prediction. Pork texture and chemical components were affected by muscle, seasons, sex and carcass weight. pH, collagen solubility, and IMF-affected pork texture.


Pork quality was affected by the season, sex, and weight of the pigs and muscle type. In this study, we determined how season, sex, weight, and muscle affected pork chemical components and texture and, how pH, collagen and intramuscular fat affected pork texture. The results showed that pork silverside was tougher than the loin, while pork collected during winter was tougher than that collected during summer. The pork shoulder had higher pH, intramuscular fat, and collagen content than silverside and loin. Pork with higher pH, collagen solubility, and intramuscular fat content would be the tenderest.


Asunto(s)
Tejido Adiposo , Colágeno , Músculo Esquelético , Estaciones del Año , Animales , Masculino , Femenino , Colágeno/química , Colágeno/metabolismo , Músculo Esquelético/química , Músculo Esquelético/fisiología , Porcinos/fisiología , Peso Corporal , Factores Sexuales , Carne/análisis , Carne/normas , Culinaria
2.
Meat Sci ; 218: 109631, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39167994

RESUMEN

Pork eating quality is affected by various factors. In this study, Longissimus thoracis et lumborum (LTL) and Semimembranosus (SM) muscles from seven genetic lines (PM-LR - Pure maternal, Landrace-type; PM-LW - Pure maternal, Large White-type; PM-D - Pure maternal, Duroc-type; PT-D - Pure terminal, Duroc-type; PT-LW - Pure terminal, Large White-type; PT-LR - Pure Terminal, Landrace-type; Comp-P × LW × D - Composite Terminal - Pietran × Large white × Duroc) were analyzed for pH, intramuscular fat (IMF) content, and collagen content and solubility. A consumer sensory test using check-all-that-apply (CATA) and biometric approaches was also conducted. The results showed that the IMF content of line PM-D was the highest (P = 0.004), while line PT-LW received the highest score in tenderness, liking of flavor, purchase intent, and quality grading (P < 0.05). Line PM-LR and PT-LR showed the lowest IMF content and were least preferred by consumers. Compared to LTL, SM showed higher pH, collagen solubility, and sensory scores in tenderness, juiciness, liking of flavor, and overall liking (P < 0.05). Different muscles and lines were associated with different CATA terms but not with differences in consumer emotional responses. pH positively influenced tenderness, juiciness, and overall liking (P < 0.05), but IMF and collagen had little effect. The flavor was the most important sensory attribute contributing to overall liking, followed by tenderness. Genetic line and muscle affected pork chemical properties and eating quality. The findings are important for the Australian pork industry to improve the eating quality of their products.

3.
Sci Total Environ ; 950: 175276, 2024 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-39102948

RESUMEN

The pervasive presence of microplastics has emerged as a pressing global environmental concern, posing threats to food security and human health upon infiltrating agricultural soils. These microplastics primarily originate from agricultural activities, including fertilizer inputs, compost-based soil remediation, irrigation, and atmospheric deposition. Their remarkable durability and resistance to biodegradation contribute to their persistent presence in the environment. Microplastics within agricultural soils have prompted concerns regarding their potential impacts on agricultural practices. Functioning as significant pollutants and carriers of microcontaminants within agricultural ecosystems, microplastics and their accompanying contaminants represent ongoing challenges. Within these soil ecosystems, the fate and transportation of microplastics can detrimentally affect plant growth, microbial communities, and, subsequently, human health via the food chain. Specifically, microplastics interact with soil factors, impacting soil health and functionality. Their high adsorption capacity for hazardous microcontaminants exacerbates soil contamination, leading to increased adverse effects on organisms and human health. Due to their tiny size, microplastic debris is easily ingested by soil organisms and can transfer through the food chain, causing physiological and/or mechanical damage. Additionally, microplastics can affect plant growth and have the potential to accumulate and be transported within plants. Efforts to mitigate these impacts are crucial to safeguarding agricultural sustainability and environmental health. Future research should delve into the long-term impacts of environmental aging processes on microplastic debris within agricultural soil ecosystems from various sources, primarily focusing on food security and human beings.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Microplásticos , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Microplásticos/análisis , Agricultura/métodos , Suelo/química
4.
J Anal Methods Chem ; 2024: 5652559, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39045342

RESUMEN

Vodka constitutes a significant sector of Vietnam's alcohol industry, including both domestic and imported varieties. However, this diversity faces challenges from illegal imports and adulterated products, threatening consumer health and brand integrity. This study employs Fourier transform infrared spectroscopy (FTIR) and inductively coupled plasma mass spectrometry (ICP-MS) to analyze 300 vodka samples from five brands collected across Hanoi. Significant variations were found in elemental compositions, with sodium concentrations ranging from 205.67 µg/L to 1269.24 µg/L and magnesium levels from 65.57 µg/L to 1453.34 µg/L. Principal Component Analysis (PCA) of the FTIR and ICP-MS data effectively differentiated the samples, with the first two principal components explaining 84.78% and 73.02% of the total variance, respectively. The PCA plots revealed distinct chemical profiles, notably isolating Rocket Vodka. These findings enhance food safety enforcement, protect consumer rights, and preserve brand reputations. The study underscores the importance of advanced analytical tools in combating beverage adulteration, ensuring public health, and maintaining market integrity, offering a replicable model for similar research in other regions.

5.
Food Chem ; 460(Pt 1): 140506, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39053267

RESUMEN

The taste of beef is caused by taste-active compounds detected in the mouth during mastication. We hypothesised that the concentration of taste-active compounds in beef is influenced by muscle-fibre-type and postmortem ageing. To test this, and unravel the underlying mechanisms, we investigated the taste-active compounds, and proteomic profiles, in beef masseter [oxidative muscle, all type I fibres) and cutaneous trunci (glycolytic muscle, mostly type II fibres) before and after 14-days postmortem ageing. Our results showed that nucleotides were initially higher and degraded slower in cutaneous trunci (P < 0.05 for both), which could be explained by the profile of nucleotide metabolism enzymes. In contrast, free amino acids were initially higher and increased more in masseter compared to cutaneous trunci (P < 0.05 for all), which might be explained by the profile and activity of proteases in these two muscles. Our results indicate the taste of beef is affected by the muscle-fibre-type and postmortem ageing.


Asunto(s)
Proteómica , Gusto , Bovinos/metabolismo , Animales , Fibras Musculares Esqueléticas/metabolismo , Metabolómica , Carne Roja/análisis , Humanos , Cambios Post Mortem , Aromatizantes/metabolismo , Aromatizantes/química
6.
Molecules ; 29(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38792114

RESUMEN

Flavonoids and stilbenoids, crucial secondary metabolites abundant in plants and fungi, display diverse biological and pharmaceutical activities, including potent antioxidant, anti-inflammatory, and antimicrobial effects. However, conventional production methods, such as chemical synthesis and plant extraction, face challenges in sustainability and yield. Hence, there is a notable shift towards biological production using microorganisms like Escherichia coli and yeast. Yet, the drawbacks of using E. coli and yeast as hosts for these compounds persist. For instance, yeast's complex glycosylation profile can lead to intricate protein production scenarios, including hyperglycosylation issues. Consequently, Corynebacterium glutamicum emerges as a promising alternative, given its adaptability and recent advances in metabolic engineering. Although extensively used in biotechnological applications, the potential production of flavonoid and stilbenoid in engineered C. glutamicum remains largely untapped compared to E. coli. This review explores the potential of metabolic engineering in C. glutamicum for biosynthesis, highlighting its versatility as a cell factory and assessing optimization strategies for these pathways. Additionally, various metabolic engineering methods, including genomic editing and biosensors, and cofactor regeneration are evaluated, with a focus on C. glutamicum. Through comprehensive discussion, the review offers insights into future perspectives in production, aiding researchers and industry professionals in the field.


Asunto(s)
Corynebacterium glutamicum , Flavonoides , Ingeniería Metabólica , Estilbenos , Corynebacterium glutamicum/metabolismo , Corynebacterium glutamicum/genética , Ingeniería Metabólica/métodos , Flavonoides/biosíntesis , Flavonoides/metabolismo , Estilbenos/metabolismo
7.
Microb Genom ; 10(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38739115

RESUMEN

Aeromonas spp. are commonly found in the aquatic environment and have been responsible for motile Aeromonas septicemia (MAS) in striped catfish, resulting in significant economic loss. These organisms also cause a range of opportunistic infections in humans with compromised immune systems. Here, we conducted a genomic investigation of 87 Aeromonas isolates derived from diseased catfish, healthy catfish and environmental water in catfish farms affected by MAS outbreaks in eight provinces in Mekong Delta (years: 2012-2022), together with 25 isolates from humans with bloodstream infections (years: 2010-2020). Genomics-based typing method precisely delineated Aeromonas species while traditional methods such as aerA PCR and MALDI-TOF were unable identify A. dhakensis. A. dhakensis was found to be more prevalent than A. hydrophila in both diseased catfish and human infections. A. dhakensis sequence type (ST) 656 followed by A. hydrophila ST251 were the predominant virulent species-lineages in diseased catfish (43.7 and 20.7 %, respectively), while diverse STs were found in humans with bloodstream infections. There was evidence of widespread transmission of ST656 and ST251 on striped catfish in the Mekong Delta region. ST656 and ST251 isolates carried a significantly higher number of acquired antimicrobial resistance (AMR) genes and virulence factors in comparison to other STs. They, however, exhibited several distinctions in key virulence factors (i.e. lack of type IV pili and enterotoxin ast in A. dhakensis), AMR genes (i.e. presence of imiH carbapenemase in A. dhakensis), and accessory gene content. To uncover potential conserved proteins of Aeromonas spp. for vaccine development, pangenome analysis has unveiled 2202 core genes between ST656 and ST251, of which 78 proteins were in either outer membrane or extracellular proteins. Our study represents one of the first genomic investigations of the species distribution, genetic landscape, and epidemiology of Aeromonas in diseased catfish and human infections in Vietnam. The emergence of antimicrobial resistant and virulent A. dhakensis strains underscores the needs of enhanced genomic surveillance and strengthening vaccine research and development in preventing Aeromonas diseases in catfish and humans, and the search for potential vaccine candidates could focus on Aeromonas core genes encoded for membrane and secreted proteins.


Asunto(s)
Aeromonas , Bagres , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Sepsis , Animales , Bagres/microbiología , Vietnam/epidemiología , Aeromonas/genética , Aeromonas/aislamiento & purificación , Aeromonas/clasificación , Aeromonas/patogenicidad , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/epidemiología , Humanos , Sepsis/microbiología , Sepsis/veterinaria , Sepsis/epidemiología , Enfermedades de los Peces/microbiología , Filogenia , Genómica , Genoma Bacteriano , Factores de Virulencia/genética , Antibacterianos/farmacología
8.
Foods ; 13(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38611414

RESUMEN

The colour of seafood flesh is often not homogenous, hence measurement of colour requires repeat measurements to obtain a representative average. The aim of this study was to determine the optimal number of repeat colour measurements required for three different devices [machine vision (digital image using camera, and computer processing); Nix Pro; Minolta CR400 colorimeter] when measuring three species of seafood (Atlantic salmon, Salmo salar, n = 8; rockling, Genypterus tigerinus, n = 8; banana prawns, Penaeus merguiensis, n = 105) for raw and cooked samples. Two methods of analysis for number of repeat measurements required were compared. Method 1 was based on minimising the standard error of the mean and Method 2 was based on minimising the difference in colour over repeat measurements. Across species, using Method 1, machine vision required an average of four repeat measurements, whereas Nix Pro and Minolta required 13 and 12, respectively. For Method 2, machine vision required an average of one repeat measurement compared to nine for Nix Pro and Minolta. Machine vision required fewer repeat measurements due to its lower residual variance: 0.51 compared to 3.2 and 2.5 for Nix Pro and Minolta, respectively. In conclusion, machine vision requires fewer repeat measurements than colorimeters to precisely measure the colour of salmon, prawns, and rockling.

9.
J Am Chem Soc ; 146(13): 9181-9190, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38528433

RESUMEN

Many unique adsorption properties of metal-organic frameworks (MOFs) have been revealed by diffraction crystallography, visualizing their vacant and guest-loaded crystal structures at the molecular scale. However, it has been challenging to see the spatial distribution of the adsorption behaviors throughout a single MOF particle in a transient equilibrium state. Here, we report three-dimensional (3D) visualization of molecular adsorption behaviors in a single crystalline particle of a MOF by in situ X-ray absorption fine structure spectroscopy combined with computed tomography for the first time. The 3D maps of water-coordinated Co sites in a 100 µm-scale MOF-74-Co crystal were obtained with 1 µm spatial resolution under several water vapor pressures. Through the visualization of the water vapor adsorption process, 3D spectroimaging revealed the mechanism and spatial heterogeneity of guest adsorption inside a single particle of a crystalline MOF.

10.
J Anal Methods Chem ; 2024: 1329212, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505133

RESUMEN

Sausage is a convenient food that is widely consumed in the world and in Vietnam. Due to the rapid development of this product, the authenticity of many famous brands has faded by the rise of adulteration. Therefore, in this study, principal component analysis (PCA) was combined with chemical analysis to identify 6 sausage brands. Sausage samples were dried and then ground to a fine powder for both instrumental analyses of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and inductively coupled plasma-mass spectrometry (ICP-MS). Dried measurements of ATR-FTIR was performed directly on the ZnSe crystal, while elemental data were obtained through microwave digestion before the ICP-MS analysis. Principal component analysis (PCA) within the framework software of XLSTAT and STATISTICA 12 was performed on the spectroscopy and elemental dataset of sausage samples. PCA visualized the distinction of 6 sausage brands on both datasets of ATR-FTIR and ICP-MS. The classification on the spectroscopy profile showed that although more than 90% variation of the dataset was explained on the first two PCs, the difference between several brands was not detected as the distribution of data overlapped with one another. The PCA observation of the elemental composition on PC1 and PC3 has separated the sausage brands into 6 distinctive groups. Besides, several key elements contributed to the brands' identification have been detected, and the most distinctive elements are Na, K, Ca, and Ba. PCA visualization showed the feasibility of the classification of sausage samples from different brands when combined with the results of FT-IR and ICP-MS methods. The experiment was able to differentiate the sausages from the 5 brands using multivariate statistics.

11.
Protein Expr Purif ; 217: 106444, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38365166

RESUMEN

The matrix of the stationary phase is a crucial element in affinity chromatography for protein purification. Various materials, including polymer or magnetic materials, have been employed as the matrix in the purification of His-tagged protein. Here, for the first time, we utilized a combination of melanin and alginate, both natural polymer materials, to synthesize Ni-melanin/alginate (Ni-M/A) beads for His-tagged protein purification. We investigated the binding of His-tagged Mpro on the Ni-M/A beads, referred to as Ni-M/A-Mpro, and assessed the elution efficiency of Mpro from the beads. Our examination involved FTIR, EDS, XRD, SDS-PAGE, and Western blotting methods. FTIR spectra revealed notable changes in the stretching patterns and intensities of hydroxyl, amine, carbonyl, imine and amide chemical groups, when Mpro protein was present in the Ni-M/A sample. XRD spectra demonstrated the occurrence of two Nickel peaks at 35-40 deg and 40-45 deg in Ni-M/A, but only one nickel peak at 35-40 deg in Ni-M/A-Mpro, indicating the binding of Mpro on the Nickel ions. EDS analysis reported a decrease in the concentration of Nickel on the surface of Ni-M/A from 16% to 7% when Mpro protein was loaded into the stationary phase. Importantly, our data indicated that the purity of the His-tagged protein Mpro after purification reached 97% after just one-step purification using the Ni-M/A stationary phase. Moreover, the binding capacity of Ni-M/A for Mpro was approximately 5.2 mg/g with recovery efficiency of 40%. Our results suggested Ni-M/A as a highly potential solid phase for affinity chromatography in the purification of His-tagged protein.


Asunto(s)
Melaninas , Níquel , Níquel/química , Histidina/química , Cromatografía de Afinidad/métodos , Iones , Polímeros , Alginatos
12.
Plant Sci ; 339: 111935, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38049038

RESUMEN

Manganese (Mn), an indispensable plant micronutrient, functions as a vital enzyme co-factor in numerous biochemical reactions. In rice, the Golgi-localized PHOTOSYNTHESIS-AFFECTED MUTANT 71-LIKE 3 (OsPML3), a member of the UNCHARACTERIZED PROTEIN FAMILY (UPF0016), plays a pivotal role in Mn homeostasis, particularly in rapidly developing tissues. This study focused on the functional characterization of another UPF0016 family member in rice, OsPML4, to elucidate its involvement in Mn homeostasis. OsPML4 had a 73% sequence identity with OsPML3 and exhibited expression in both shoots and roots, albeit at a lower transcriptional level than OsPML3. Furthermore, subcellular localization studies confirmed that OsPML4 localizes in the Golgi apparatus. Notably, heterologous expression of OsPML4 restored growth in the Mn uptake-deficient yeast strain Δsmf1 under Mn-limited conditions. Under Mn-deficient conditions, OsPML4 knockout exacerbated the decline in shoot dry weight and intensified necrosis in young leaves of OsPML3 knockout lines, which displayed stunted growth. The Mn concentration in OsPML3PML4 double knockout lines was lower than in wild-type (WT) and OsPML3 knockout lines. At the reproductive phase, OsPML3PML4 double knockout lines exhibited reduced fertility and grain yield compared to WT and OsPML3 knockout lines. Notably, reductions were observed in the deposition of cell wall polysaccharides and the content of Lea (Lewis A structure)-containing N-glycans in the young leaves of OsPML3PML4 double knockout lines, surpassing the reductions in WT and OsPML3 knockout lines. These findings underscore the significance of OsPML4 in Mn homeostasis in the Golgi apparatus, where it co-functions with OsPML3 to regulate cell wall polysaccharide deposition and late-stage Golgi N-glycosylation.


Asunto(s)
Proteínas de Transporte de Catión , Oryza , Manganeso/metabolismo , Oryza/genética , Oryza/metabolismo , Aparato de Golgi/metabolismo , Homeostasis , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte de Catión/metabolismo
13.
Meat Sci ; 209: 109395, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38141536

RESUMEN

Variations in pork quality impact consumer acceptance, and fibre type differences between muscles contribute to this variation. The aim was to investigate the influence of variations in muscle fibre types and protein denaturation peaks across four pork muscles and the influence of ageing and cooking temperature on longissimus quality traits. The longissimus, masseter, cutaneous trunci, and psoas major from 13 carcases were removed 1-day postmortem and subjected to 0- or 14-days ageing (d0, d14). Quality traits, protein denaturation peak temperature (DSC), fibre diameter and fibre type proportions were measured. Cook loss for longissimus was similar on d0 and d14, but was higher on d14 for masseter, cutaneous trunci, and psoas major. Warner-Bratzler shear force was highest, and ultimate pH was lowest, for longissimus, and similar among cutaneous trunci, masseter, and psoas major. Masseter had lowest L* and highest a* and longissimus and cutaneous trunci had highest L* and lowest a*. The DSC temperature peaks for longissimus occurred at lower temperatures relative to the other muscles. Fibre diameter was largest for type-IIb fibres relative to type-IIa and type-I. Longissimus and cutaneous trunci had predominantly type-IIb glycolytic (71%, 51% respectively), masseter had predominantly type-IIa intermediate (50%) and psoas major had predominantly type-I oxidative (48%) fibres. The glycolytic longissimus had the lowest DSC temperature peaks and the lowest quality meat. Masseter had the highest proportion of type-I fibres but was generally similar in quality traits to psoas major, and also similar to cutaneous trunci which had more glycolytic fibres than masseter.


Asunto(s)
Carne de Cerdo , Carne Roja , Animales , Porcinos , Músculo Esquelético/metabolismo , Temperatura , Desnaturalización Proteica , Fibras Musculares Esqueléticas/metabolismo , Culinaria , Músculos Psoas
14.
J Anal Methods Chem ; 2023: 1465773, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37928250

RESUMEN

Fingerprinting techniques, which utilize the unique chemical and physical properties of food samples, have emerged as a promising approach for food authentication and traceability. Recent studies have demonstrated significant advancements in food authentication through the use of fingerprinting methods, such as multivariate statistical analysis techniques applied to trace elements and isotope ratios. However, further research is required to optimize these methods and ensure their validity and reliability in real-world applications. In this study, the inductively coupled plasma mass spectrometry (ICP-MS) analytical method was employed to determine the content of 21 elements in 300 cashew nut (Anacardium occidentale L.) samples from 5 brands. Multivariate statistical methods, such as principal components analysis (PCA), were employed to analyze the data obtained and establish the provenance of the cashew nuts. While cashew nuts are widely marketed in many countries, no universal method has been utilized to differentiate the origin of these nuts. Our study represents the initial step in identifying the geographical origin of commercial cashew nuts marketed in Vietnam. The analysis showed significant differences in the means of 21 of the 40 analyzed elements among the cashew nut samples from the 5 brands, including 7Li, 11B, 24Mg, 27Al, 44Ca, 48Ti, 51V, 52Cr, 55Mn, 57Fe, 60Ni, 63Cu, 66Zn, 93Nb, 98Mo, 111Cd, 115In, 121Sb, 138Ba, 208Pb, and 209Bi. The PCA analysis indicated that the cashew nut samples can be accurately classified according to their original locations. This research serves as a prerequisite for future studies involving the combination of elemental composition analysis with statistical classification methods for the accurate establishment of cashew nut provenance, which involves the identification of key markers for the original discrimination of cashew nuts.

15.
Sensors (Basel) ; 23(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37960447

RESUMEN

Artificial intelligence (AI) radar technology offers several advantages over other technologies, including low cost, privacy assurance, high accuracy, and environmental resilience. One challenge faced by AI radar technology is the high cost of equipment and the lack of radar datasets for deep-learning model training. Moreover, conventional radar signal processing methods have the obstacles of poor resolution or complex computation. Therefore, this paper discusses an innovative approach in the integration of radar technology and machine learning for effective surveillance systems that can surpass the aforementioned limitations. This approach is detailed into three steps: signal acquisition, signal processing, and feature-based classification. A hardware prototype of the signal acquisition circuitry was designed for a Continuous Wave (CW) K-24 GHz frequency band radar sensor. The collected radar motion data was categorized into non-human motion, human walking, and human walking without arm swing. Three signal processing techniques, namely short-time Fourier transform (STFT), mel spectrogram, and mel frequency cepstral coefficients (MFCCs), were employed. The latter two are typically used for audio processing, but in this study, they were proposed to obtain micro-Doppler spectrograms for all motion data. The obtained micro-Doppler spectrograms were then fed to a simplified 2D convolutional neural networks (CNNs) architecture for feature extraction and classification. Additionally, artificial neural networks (ANNs) and 1D CNN models were implemented for comparative analysis on various aspects. The experimental results demonstrated that the 2D CNN model trained on the MFCC feature outperformed the other two methods. The accuracy rate of the object classification models trained on micro-Doppler features was 97.93%, indicating the effectiveness of the proposed approach.


Asunto(s)
Inteligencia Artificial , Radar , Humanos , Procesamiento de Señales Asistido por Computador , Caminata , Análisis de Fourier
16.
BMJ Glob Health ; 8(11)2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37935520

RESUMEN

INTRODUCTION: It is well known that influenza and other respiratory viruses are wintertime-seasonal in temperate regions. However, respiratory disease seasonality in the tropics is less well understood. In this study, we aimed to characterise the seasonality of influenza-like illness (ILI) and influenza virus in Ho Chi Minh City, Vietnam. METHODS: We monitored the daily number of ILI patients in 89 outpatient clinics from January 2010 to December 2019. We collected nasal swabs and tested for influenza from a subset of clinics from May 2012 to December 2019. We used spectral analysis to describe the periodic signals in the system. We evaluated the contribution of these periodic signals to predicting ILI and influenza patterns through lognormal and gamma hurdle models. RESULTS: During 10 years of community surveillance, 66 799 ILI reports were collected covering 2.9 million patient visits; 2604 nasal swabs were collected, 559 of which were PCR-positive for influenza virus. Both annual and nonannual cycles were detected in the ILI time series, with the annual cycle showing 8.9% lower ILI activity (95% CI 8.8% to 9.0%) from February 24 to May 15. Nonannual cycles had substantial explanatory power for ILI trends (ΔAIC=183) compared with all annual covariates (ΔAIC=263) in lognormal regression. Near-annual signals were observed for PCR-confirmed influenza but were not consistent over time or across influenza (sub)types. The explanatory power of climate factors for ILI and influenza virus trends was weak. CONCLUSION: Our study reveals a unique pattern of respiratory disease dynamics in a tropical setting influenced by both annual and nonannual drivers, with influenza dynamics showing near-annual periodicities. Timing of vaccination campaigns and hospital capacity planning may require a complex forecasting approach.


Asunto(s)
Gripe Humana , Virosis , Humanos , Gripe Humana/epidemiología , Estaciones del Año , Factores de Tiempo , Vietnam/epidemiología
17.
Mol Genet Genomic Med ; 11(12): e2263, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37547970

RESUMEN

BACKGROUND: Brugada syndrome (BrS) is a rare genetic disease that causes sudden cardiac death (SCD) and arrhythmia. SCN5A pathogenic variants (about 30% of diagnosed patients) are responsible for BrS. AIMS: Lack of knowledge regarding molecular characteristics and the correlation between genotype and phenotype interfere with the risk stratification and finding the optimal treatment in Vietnam. Therefore, we identified SCN5A variants and evaluated the genotype-phenotype correlation of BrS on 117 Vietnamese probands. MATERIALS AND METHODS: The clinical characteristics and blood samples of BrS patients were collected. To determine SCN5A variants, Sanger sequencing was conducted, and subsequently, these variants were analyzed by bioinformatic tools. RESULTS: In this cohort, the overall rate of detected variants in SCN5A was 25.6%, which could include both pathogenic and benign variants. In genetic testing, 21 SCN5A variants were identified, including eight novels and 15 published variants. Multiple bioinformatic tools were used to predict variant effect with c.551A>G, c.1890+14G>A, c.3338C>T, c.3578G>A, and c.5484C>T as benign, while other variants were predicted as disease-causing. The family history of SCD (risk ratio [RR] = 4.324, 95% CI: 2.290-8.269, p < 0.001), syncope (RR = 3.147, 95% CI: 1.668-5.982, p = 0.0004), and ventricular tachycardia/ventricular fibrillation (RR = 3.406, 95% CI: 1.722-5.400, p = 0.0035) presented a significantly higher risk in the SCN5A (+) group, consisting of individuals carrying any variant in the SCN5A gene, compared to SCN5A (-) individuals. CONCLUSION: The results contribute to clarifying the impact of SCN5A variants on these phenotypes. Further follow-up studies need to be carried out to understand the functional effects of these SCN5A variants on the severity of BrS.


Asunto(s)
Síndrome de Brugada , Humanos , Síndrome de Brugada/genética , Síndrome de Brugada/complicaciones , Mutación , Genotipo , Pruebas Genéticas , Estudios de Asociación Genética , Fibrilación Ventricular , Muerte Súbita Cardíaca/etiología , Canal de Sodio Activado por Voltaje NAV1.5/genética
18.
Front Plant Sci ; 14: 1194887, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37426979

RESUMEN

Elimination of chemically synthesized pesticides, such as fungicides and nematicides, in agricultural products is a key to successful practice of the Vietnamese agriculture. We describe here the route for developing successful biostimulants based on members of the Bacillus subtilis species complex. A number of endospore-forming Gram-positive bacterial strains with antagonistic action against plant pathogens were isolated from Vietnamese crop plants. Based on their draft genome sequence, thirty of them were assigned to the Bacillus subtilis species complex. Most of them were assigned to the species Bacillus velezensis. Whole genome sequencing of strains BT2.4 and BP1.2A corroborated their close relatedness to B. velezensis FZB42, the model strain for Gram-positive plant growth-promoting bacteria. Genome mining revealed that at least 15 natural product biosynthesis gene clusters (BGCs) are well conserved in all B. velezensis strains. In total, 36 different BGCs were identified in the genomes of the strains representing B. velezensis, B. subtilis, Bacillus tequilensis, and Bacillus. altitudinis. In vitro and in vivo assays demonstrated the potential of the B. velezensis strains to enhance plant growth and to suppress phytopathogenic fungi and nematodes. Due to their promising potential to stimulate plant growth and to support plant health, the B. velezensis strains TL7 and S1 were selected as starting material for the development of novel biostimulants, and biocontrol agents efficient in protecting the important Vietnamese crop plants black pepper and coffee against phytopathogens. The results of the large-scale field trials performed in the Central Highlands in Vietnam corroborated that TL7 and S1 are efficient in stimulating plant growth and protecting plant health in large-scale applications. It was shown that treatment with both bioformulations resulted in prevention of the pathogenic pressure exerted by nematodes, fungi, and oomycetes, and increased harvest yield in coffee, and pepper.

19.
Humanit Soc Sci Commun ; 10(1): 329, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37361101

RESUMEN

The present study examines the roles of internal communication (IC), job engagement (JE), organisation engagement (OE) and job satisfaction (JS) in producing employee loyalty (EL) based on the social exchange theory. This study employed an online questionnaire-based survey design to collect data from 255 respondents from higher education institutions (HEIs) in Binh Duong province using convenience and snowball sampling techniques. Data analyses and hypothesis testing were carried out using the partial least squares structural equation modelling (PLS-SEM). The findings show that all relationships are significantly validated, except for the JE-JS relationship. Our work is the first to investigate employee loyalty in the HEI context of an emerging economy such as Vietnam by incorporating internal communication, employee engagement (including job and organisation engagement) and job satisfaction to develop and validate a research model for the study. This study is expected to contribute to the theory and advance our understanding of different mechanisms that job engagement, organisation engagement and job satisfaction can play in the relationship between internal communication and employee loyalty.

20.
Heliyon ; 9(4): e15008, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37123914

RESUMEN

Clematis armandii has been used in many Chinese traditional patent medicines all over the world as a form of Caulis Clematidis Armandii. However, it has often been adulterated by Aristolochia manshuriensis, and Iodes vitiginea. A. manshuriensis must not be part of any herbal medicines because it contains aristolochic acid I, a nephrotoxin and potential carcinogen. The current pharmacopoeial methods have had limitation for differentiation of C. armandii from its adulterants. Thus, a specific, comprehensive, sensitive, and reproducible HPTLC/HPLC for quality control of C. armandii was proposed. Oleanolic acid from C. armandii has been isolated by vacuum liquid chromatography and column chromatography. The purified compound has been identified using Ultra Violet spectrophotometry (UV-Vis), Fourier Transform Infrared (FTIR), mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy. Therefore, oleanolic acid should be detected for positive identification of Caulis Clematis Armandii. Minimum content of oleanolic acid can be evaluated by the validated HPTLC procedure proposed as well.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA