Red Plates Research Articles

Production and analysis of synthesized bacterial cellulose by Enterococcus faecalis strain AEF using Phoenix dactylifera and Musa acuminata fruit extracts.

Bacterial cellulose (BC) is a highly versatile biopolymer renowned for its exceptional mechanical strength, water retention, and biocompatibility. These properties make it a valuable material for various industrial and biomedical applications. In this study, Enterococcus faecalis synthesized extracellular BC, utilizing Phoenix dactylifera and Musa acuminata fruit extracts as sustainable carbon sources. LC-MS analysis identified glucose as the primary carbohydrate in these extracts, providing a suitable substrate for BC production. Scanning Electron Microscopy (SEM) revealed a network of BC nanofibers on Congo red agar plates. ATR-FTIR spectroscopy confirmed the presence of characteristic cellulose functional groups, further supporting BC synthesis. X-ray diffraction (XRD) analysis indicated a high crystallinity index of 71%, consistent with the cellulose I structure, as evidenced by peaks at 16.22°, 21.46°, 22.52°, and 34.70°. Whole-genome sequencing of E. faecalis identified vital genes involved in BC biosynthesis, including bcsA, bcsB, diguanylate cyclase (DGC), and 6-phosphofructokinase (pfkA). Antibiotic susceptibility tests revealed resistance to cefotaxime, ceftazidime, and ceftriaxone, while susceptibility to imipenem was observed. Quantitative assessment demonstrated that higher concentrations of fruit extracts (5.0-20mg/mL) significantly enhanced BC production. Cytotoxicity testing via the MTT assay confirmed excellent biocompatibility with NIH/3T3 fibroblast cells, showing high cell viability (97-105%). Unlike commonly studied Gram-negative bacteria like Acetobacter xylinum for BC production, this research focuses on Gram-positive Enterococcus faecalis and utilizes Phoenix dactylifera and Musa acuminata fruit extracts as carbon sources. This approach offers a sustainable and promising avenue for BC production.

Espérance Bridge

Espérance Bridge is one of the final infrastructure elements to be delivered on the King’s Cross estate in central London. The 25 metre footbridge spans over the Regent’s Canal to connect the major railway stations and Pancras Square in the south with shopping and eating hotspots, Granary Square and Coal Drops Yard in the north. As part of the original King’s Cross master plan, the bridge strengthens the link between the two halves of the site, enabling visitor flow and giving residents better access to public transport. The bridge also enlivens the canal corridor, providing a platform to observe Camley Street Natural Park to the west and the Ghat Steps to the east. Designed and constructed during a global pandemic and opening in the summer of 2021, the bridge is an innovative take on a traditional warren truss bridge that uses tapering and folded steel plates to create an elegant and sculptural form. The bold pomegranate red carbon steel plates set against the diagonal stainless steel tension ties illustrate the structural behaviour of the warren truss. Re-use of existing foundations to support the bridge ensured a seamless integration of the abutments into the setting, whilst also providing cost and carbon benefits.

Impact of a random TN5 mutation on endoglucanase secretion in ruminal cellulolytic Escherichia coli

ObjectiveMost protein secretion systems are found in gram-negative bacteria, but the mechanism of endoglucanase (BcsZ) secretion in Escherichia coli (E. coli) remains unclear. MethodsIn this study, we used JBZ-DH5α (which overexpresses BcsZ on the E. coli DH5α genome) as the initial strain. A mutant library was created by randomly inserting the TN5 transposon into the genome, and mutants with reduced transparent circles were identified on Congo red plates. The insertion sites of transposons in the genome were determined through whole-genome sequencing. ResultsThe results revealed that the genes rnc, lon, and suhB, which encode RNC-ribonuclease III (RNC), LON-protease (LON), and SuhB-inositol phosphatase (SuhB), respectively, were disrupted. BcsZ secretion decreased in E. coli DH5α when the lon, rnc, or suhB genes were deleted, but the overexpression of these genes restored their secretion levels. ConclusionThese findings suggest that the lon, rnc, and suhB genes play a role in BcsZ secretion in E. coli, potentially enhancing our knowledge of BcsZ secretion and offering a strategy to increase protein secretion in E. coli as a cell factory.

Bioproduction of exopolysaccharides by lactic acid bacteria using agave by-products

The capacity to produce exopolysaccharides (EPS) is well known among several microorganisms, especially lactic acid bacteria (LAB). However, the physiological role of these polymers has yet to be elucidated. Nevertheless, it has been observed that LAB growth conditions and adaptation to external environments and substrates are directly related to EPS biosynthesis. This study aimed to evaluate alternative carbon sources from agave by-products to synthesize EPS with LAB. Native LAB from the genera Lactococcus and Lactiplantibacillus were evaluated for their ability to produce EPS from simple carbon sources; they showed potential to produce EPS, presenting positive results on Congo red plates using glucose and fructose as carbon sources. In addition, native LAB could synthesize EPS from agave leaves and bagasse. L. plantarum ITD-ZC-107 stand out in the production of EPS, especially from bagasse. Thermostability of EPS from the evaluated carbon sources was analyzed. EPS from agave leaves and bagasse showed a higher degradation temperature than the ones obtained from glucose and sucrose, indicating better thermo-resistance.

Effect of Shape, Size, and Color of the Food Plate on Consumer Perception of Energy Value, Portion Size, Attractiveness, and Expected Price of Dessert.

The development of new dishes in the catering services market requires an understanding of consumers' needs, expectations, and motivations for their choices. The effect of the serving method of a dessert on customers' perceptions of its visual appeal, portion size, energy value, and expected price was evaluated. The study involved the presentation of desserts on plates of various sizes, shapes, and colors. The study was carried out among 1005 respondents using the CAWI method. Our findings revealed that along with an increasing plate size from a diameter of ϕ24-27 cm to ϕ31 cm, the ratings of the dish's perceived appearance (p ≤ 0.001), portion size (p ≤ 0.001), and energy value (p ≤ 0.01) decreased. Plate shape influenced the perceived appearance of the dessert. When placed on a square platter, round desserts were considerably (p ≤ 0.05) less appealing. The color of the plate had a significant influence (p ≤ 0.001) on the dish's perceived appearance and estimated monetary value, and it evoked more sensory-hedonic impressions. Red-plate and white-plate desserts were liked less than black-plate desserts, but color-plated desserts were perceived as more expensive than those served on white dishes. Consumers perceived bright desserts on white plates as traditional, natural, and boring; those on black plates as modern, appetizing, and aesthetic; and those served on red plates as artificial, unsightly, and unappetizing. Higher consumer food neophobia led to a lower rating related to appearance and price perceptions, but elevated perceptions of portion size and energy value appraisal. Our results may be used in the marketing of gastronomic dishes.

Phenotypic and Genotypic Study of Staphylococcus Haemolyticus and Staphylococcus Warneri Clinically Isolated from the Bloodstream

Background: The Staphylococcus haemolyticus and Staphylococcus warneri are coagulase-negative staphylococci (CoNS) as part of human skin’s natural flora. In recent years, CoNS has increased its visibility as opportunistic pathogens acquired in hospital patients. This study aims to isolate S. haemolyticus and S. warneri strains from patients with bloodstream infections and to analyze the antimicrobial profile of these bacteria by molecular detection of the mecA gene. Materials and Methods: Four hundred and twenty-three clinical blood samples were collected from patients admitted to general three hospitals in Hilla city, Iraq, during the period from September 2021 to July 2022. Blood samples were inoculated immediately into blood bottles containing 70 ml of Brain-Heart Infusion Broth. All isolates were identified by morphology, biochemical tests, and VITEK 2 automated system (bioMerieux, France). The Congo red agar plate test was used to detect biofilm production. The mecA gene was detected by conventional polymerase chain reaction. Results: S. haem olyticus (nine isolates) and S. warneri (six isolates) were detected out of 423 clinical blood samples. Molecular detection of the mecA gene was detected in all 15 isolates. As well 11 (73.3%) isolates were β-lactam resistant and biofilm production. The results of oxacillin-resistance minimum inhibitory concentration (MIC) (≥4 mg/ml) showed that 11 (73.3%) of the 15 isolates were oxacillin and methicillin-resistant CoNS (MR-CoNS). Susceptibility to various isolates (MICs µg/ml) using VITEK 2 system showed erythromycin (≥8 µg/ml), rifampin (≥4 µg/ml), clindamycin (≥4 µg/ml), and trimethoprim-sulfamethoxazole (≥4 µg/ml) resistance were (80%), (13.3%), (20%), and (53.3%), respectively. All isolates were (100%) sensitive to linezolid (≥8 µg/ml) and teicoplanin (≥32 µg/ml). Conclusions: The S. haemolyticus and S. warneri are serious infections associated with bacteremia and septicemia infections. Linezolid, teicoplanin, and rifampin are the drug of choice for the treatment of infections caused by MR-CoNS isolates. A high rate of the mecA gene and biofilm production is present in these bacteria.

Ultrasonic-assisted extraction, anti-biofilm activity, and mechanism of action of Ku Shen (Sophorae Flavescentis Radix) extracts against Vibrio parahaemolyticus.

The objective of this study is to optimize the ultrasonic-assisted extraction process of Ku Shen (Sophorae Flavescentis Radix) extracts (KSE) against Vibrio parahaemolyticus and explore their anti-biofilm activity and mechanism of action. The ultrasonic-assisted extraction process of KSE optimized by single factor experiment, Box-Behnken design and response surface methodology was as follows: 93% ethanol as solvent, liquid/material ratio of 30 mL/g, ultrasonic power of 500 W, extraction temperature of 80°C and time of 30 min. Under these conditions, the diameter of inhibition circle of KSE was 15.60 ± 0.17 mm, which had no significant difference with the predicted value. The yield of dried KSE is 32.32 ± 0.57% and the content of total flavonoids in KSE was 57.02 ± 5.54%. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of KSE against V. parahaemolyticus were 0.25 and 0.5 mg/mL, respectively. Crystal violet staining, Congo red plate, spectrophotometry, CCK-8 and scanning electron microscopy were used to investigate the activity and mechanism of action of KSE against V. parahaemolyticus biofilm. The results showed that the sub-MIC of KSE could significantly inhibit biofilm formation, reduce the synthesis of polysaccharide intercellular adhesin (PIA) and the secretion of extracellular DNA. In addition, the inhibition rate of biofilm formation and clearance rate of mature biofilm of 1.0 mg/mL KSE were 85.32 and 74.04%, and the reduction rate of metabolic activity of developing and mature biofilm were 77.98 and 74.46%, respectively. These results were confirmed by visual images obtained by scanning electron microscopy. Therefore, KSE has the potential to further isolate the anti-biofilm agent and evaluate it for the preservation process of aquatic products.

In vitro ANALYSIS OF BIOFILM FORMATION AND ANTIBIOTIC RESISTANCE OF UROPATHOGENIC Escherichia coli

Urinary tract infections are an exceedingly common worldwide problem, caused mostly by Gram-negative bacteria, especially Escherichia coli. Microbial biofilms are considered a serious public health problem. The potential of uropathogenic E. coli (UPEC) to produce biofilm was explored in the present study. The Congo red agar, tube- and tissue culture plate methods were used to evaluate the formation of biofilm by E. coli isolates. Of the 155 isolates, 101, 106 and 90 isolates were positive for these three methods, respectively. Subsequently, the sensitivity of E. coli isolates to antimicrobial agents (amikacin, cefepime, cefixime, cefotaxime, cefpodoxime, ceftazidime, ceftriaxone, ciprofloxacin, nitrofurantoin, gentamycin, nalidixic acid, ofloxacin and pefloxacin) was tested. There was no difference in the rate of biofilm detection between Congo red agar method and tube method. The antibiotic sensitivity test revealed that the biofilm producing isolates were multi-drug resistant. The study emphasized the necessity for developing alternative therapeutic approaches to overcome multi drug resistance arising from biofilm formation of UPEC.

Grewia tenax bark extract mediated silver nanoparticles as an antibacterial, antibiofilm and antifungal agent

Grewia tenax plant possesses many medicinal qualities that can be harnessed for bio-applications via nanotechnology in a cost-effective and environment-friendly manner. The synthesised silver nanoparticles (GTB-AgNPs) from Grewia tenax bark extract were first detected by observing the change in colour from yellowish brown to dark brown and confirmed by UV–vis spectroscopy. UV–vis spectral analysis recorded the surface plasmon resonance at 420 nm. In the current research, several process parameters (time, temperature, concentration of AgNO3 and the ratio of extract to AgNO3) were adjusted by using one variable at a time (OVAT) approach. Spectroscopy accompanied by dynamic light scattering (DLS), x-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive x-ray (EDX) determines the size, nature, morphological variations and chemical constituents of GTB-AgNPs. The size range was found within 35−45 nm and the image clearly showed that the GTB-AgNPs were spherical in shape and well dispersed in nature. Zeta potential and Fourier-transform infrared spectroscopy (FTIR) were done to analyse GTB-AgNPs stability, dispersion and the biomolecules in aqueous bark extract liable for the bioreduction of silver particles. These GTB-AgNPs showed excellent antibacterial action against Gram-positive (S. aureus and B. subtilis) and Gram-negative bacteria (P. aeruginosa and E. coli) which was observed by disc diffusion assay. Congo red agar plate (CRA) assay effectively unveiled the antibiofilm proficiency of the particles. These studies displayed a reduction in bacterial sustainability and the formation of exopolysaccharides. Disc diffusion assay confirmed the antifungal competency against A. niger and C. albicans. SEM was performed to elucidate the intracellular breakage and morphological transformations in cells of Gram-positive bacteria and fungi after treatment with GTB-AgNPs. The current study, therefore, enlightened applications of GTB-AgNPs as an efficient antimicrobial agent and applicable substitute in the pharmaceutical area.

Epithelial Cell Infection Analyses with Shigella.

The human-adapted enteric bacterial pathogen Shigella causes millions of infections each year, creates long-term growth effects among pediatric patients, and is a leading cause of diarrheal deaths worldwide. Infection induces watery or bloody diarrhea as a result of the pathogen transiting the gastrointestinal tract and infecting the epithelial cells lining the colon. With staggering increases in antibiotic resistance and the current lack of approved vaccines, standardized research protocols are critical to studying this formidable pathogen. Here, methodologies are presented to examine the molecular pathogenesis of Shigella using in vitro analyses of bacterial adherence, invasion, and intracellular replication in colonic epithelial cells. Prior to infection analyses, the virulence phenotype of Shigella colonies was verified by the uptake of the Congo red dye on agar plates. Supplemented laboratory media can also be considered during bacterial culturing to mimic in vivo conditions. Bacterial cells are then used in a standardized protocol to infect colonic epithelial cells in tissue culture plates at an established multiplicity of infection with adaptations to analyze each stage of infection. For adherence assays, Shigella cells are incubated with reduced media levels to promote bacterial contact with epithelial cells. For both invasion and intracellular replication assays, gentamicin is applied for various time intervals to eliminate extracellular bacteria and enable assessment of invasion and/or the quantification of intracellular replication rates. All infection protocols enumerate adherent, invaded, and/or intracellular bacteria by serially diluting infected epithelial cell lysates and plating bacterial colony forming units relative to infecting titers on Congo red agar plates. Together, these protocols enable independent characterization and comparisons for each stage of Shigella infection of epithelial cells to study this pathogen successfully.

Reinvestigation of the 1978 Gilf El Kebir earthquake, Egypt

ABSTRACT Four significant earthquakes located in the southern portion of the Western Desert were investigated to better understand the area tectonics. The retrieved solution of 9 December 1978, indicates a pure strike solution by using FOCMEC software, which our solution differs from the solution established in an earlier study. The focal mechanism solutions of the four events in the southern part of the Western Desert demonstrate a strike-slip faulting regime along E-W oriented faults, in contrast to the solutions for earthquakes in Northern Egypt, which exhibited normal faulting mechanisms with small strike-slip components. Forces exerted as a result of differences in the divergent spreading rates along the Red Sea plate boundary North and South of the zone between 22° and 24° N may lead to second-order stress fields. This, in turn causes an E-W shear couple that is directed towards the southern part of the Western Desert and rejuvenation of the E-W trending faults. The 1984 Abu Dabbab earthquake, which occurred near the Red Sea coast South of 24° N, provides support to this argument and exhibited a mechanism similar to the four events that took place in the southern part of the Western Desert.

Antibiotic Resistance Profile of Biofilm Producing Staphylococci Isolated from Different Clinical Samples

Biofilm mediated infections by Staphylococci have a significant negative impact on patient health and necessitate reliable method for detecting biofilm producers. The ability of isolates to produce biofilm makes them resistant to host immune response as well as available antibiotics. This study aims to detect biofilm producing ability among clinical staphylococci by phenotypic methods and presence of icaAD genes and determine their antibiotic profile. A total of 350 different clinical specimens received in the KIST Medical hospital, Gwarko, Nepal was examined from July 2018 to January 2019 and Staphylococci were identified following standard microbiological procedure. The antibiotic resistivity pattern was detected by Kirby Bauer disc diffusion method whereas biofilm formation was detected by three phenotypic methods viz. congo red agar (CRA), tube method (TM) and tissue culture plate (TCP) method. Furthermore, icaAD genes were detected by PCR method. Chi-square test and independent sample t-test were employed to calculate the significance. A total of 161 Staphylococci were isolated comprising S. aureus (63, 39.1%) and coagulase negative staphylococci (CNS) (98, 60.9%). Most isolates were found to be resistant to penicillin and erythromycin. Strong biofilm formation was detected among 6 (3.7%), 22 (13.7%) and 35 (21.7%) by CRA, TM and TCP method respectively. Similarly, icaAD genes were detected among 24 (14.9%) isolates. Staphylococci isolated from clinical sample showed biofilm forming ability by both phenotypic and genotypic method. The biofilm producing isolates were found to be more resistant to antibiotics than their planktonic counterparts with 56 (89%) and 65 (66%) S. aureus and CNS observed as methicillin resistant respectively. Regular surveillance of biofilm formation by Staphylococci and their antimicrobial resistance profile may lead to early treatment of Staphylococcal infection.

Investigation and analysis of occupational hazard factors in different industries in Tongliao City

Objective: To investigate the occupational hazard factors of different industries in Tongliao City, and to provide scientific basis for the prevention and control of occupational disease in Tongliao City. Methods: In July 2021, the detection data of coal dust, silica dust, cement dust, benzene, noise and other occupational hazard factors, as well as the occupational health examination data of workers in various positions of 104 enterprises in different industries in Tongliao City were cllected and anylazed. χ(2) test was used to analyze the results of chest radiography of workers in different age groups. Results: A total of 104 enterprises were investigated, and the median time-weighted average concentration (C(TWA)) of coal dust, silic a dust, cement dust and benzene in contact with test posts were 0.94, 0.30, 0.70 and 0.95 mg/m(3), respectively. The median 8 h equivalent sound level (L(EX, 8 h)) of noise was 74.1 dB (A) . The over standard rates of silica dust, cement dust and noise contact positions were 10.83% (16/240) , 7.14% (2/28) and 0.48% (3/628) , respectively. The differences of chest X-ray examination of coal dust and silica dust workers in different working ages were statistically significant (χ(2)=218.50, 531.80, P<0.001) . The difference of hearing threshold of noise workers with different working age was statistically significant (χ(2)=1290.00, P<0.001) . The rates of leukopenia and neutropenia were 41.90% (44/105) and 20.95% (22/105) in benzene exposed workers. The positive rate of brucella exposure workers was 1.33% (1/75) for tiger red plate agglutination test and 3.23% (3/93) for tube agglutination test. Conclusion: Silica dust, cement dust and noise exceed the standard in some posts and places in the Tongliao City, and some workers are infected with Brucella. In the future, we can focus on monitoring noise-generating posts, strengthen supervision and implement prevention and control measures to reduce the incidence of occupational diseases.

Process optimization of malachite green degradation by mixed biofilm positive bacteria: Application of Box–Behnken designs, RSM and whole genome sequences analysis

Bacterial biofilm positive strains recovered from engine oil polluted-soil was investigated for its capacity to remove malachite green (MG) in mineral salt solution. Box–Behnken designs combining four factors (glucose, yeast extract, temperature and agitation) with three levels (−1, 0, +1) was used to found the best biotic and abiotic conditions for MG removal. The biodegradation potential of the selected microbial consortium was also confirmed using analytical techniques. Then, whole genome sequencing (WGS) analysis were performed to detect genes related to biofilm formation and chemicals biodegradation. Our results showed that the selected strains (G5, G13 and G15) were able to form biofilm on congo red agar plates developing almost black, very black and almost black colonies respectively. Experimental results using Box-Behnken designs showed that decolorization rate of MG reach 89.35% in these optimized conditions: glucose (2%), yeast extract (1%), temperature (40 °C), and agitation (150 rpm). Molecular investigation revealed that the isolated strains were identified as Cronobacter sakazakii G5, Enterobacter hormaechei G13, and Klebsiella pneumoniae G15 based on the whole genome sequences . Whole genome sequences analysis demonstrated the presence of genes involved in biofilm formation as well as dyes and chemical detoxification. The findings presented here provide useful information for development an efficient microbial consortium, formed by adherent bacteria, able to remove dye from coloured wastewater.

Antimicrobial Resistance Profiles, Virulence Determinants, and Biofilm Formation in Enterococci Isolated from Rhesus Macaques (Macaca mulatta): A Potential Threat for Wildlife in Bangladesh?

Enterococci are commensal bacteria that inhabit the digestive tracts of animals and humans. The transmission of antibiotic-resistant genes through human-animal contact poses a potential public health risk worldwide, as zoonoses from wildlife reservoirs can occur on every continent. The purpose of this study was to detect Enterococcus spp. in rhesus macaques (Macaca mulatta) and to investigate their resistance patterns, virulence profiles, and biofilm-forming ability. Conventional screening of rectal swabs (n = 67) from macaques was followed by polymerase chain reaction (PCR). The biofilm-forming enterococci were determined using the Congo red agar plate assay. Using the disk diffusion test (DDT), antibiogram profiles were determined, followed by resistance and virulence genes identification by PCR. PCR for bacterial species confirmation revealed that 65.7% (44/67) and 22.4% (15/67) of the samples tested positive for E. faecalis and E. faecium, respectively. All the isolated enterococci were biofilm formers. In the DDT, enterococcal isolates exhibited high to moderate resistance to penicillin, rifampin, ampicillin, erythromycin, vancomycin, and linezolid. In the PCR assays, the resistance gene blaTEM was detected in 61.4% (27/44) of E. faecalis and 60% (9/15) of E. faecium isolates. Interestingly, 88.63 % (39/44) of E. faecalis and 100% (15/15) of E. faecium isolates were phenotypically multidrug-resistant. Virulence genes (agg, fsrA, fsrB, fsrC, gelE, sprE, pil, and ace) were more frequent in E. faecalis compared to E. faecium; however, isolates of both Enterococcus spp. were found negative for the cyl gene. As far as we know, the present study has detected, for the first time in Bangladesh, the presence of virulence genes in MDR biofilm-forming enterococci isolated from rhesus macaques. The findings of this study suggest employing epidemiological surveillance along with the one-health approach to monitor these pathogens in wild animals in Bangladesh, which will aid in preventing their potential transmission to humans.

Effects of Food Plate Size and Color on Visual Perception of Satiety in Adolescents; a New Strategy toward Weight Management.

Adolescence obesity and its health consequent on adulthood is affected by various environmental factors. Recently, dishware size or color is considered as a probable critical point to manage intake and weight. We investigated visual perception effects of plate size and color on fullness sensation regarding the Body Mass Index (BMI) for age percentiles in Tehran, Iran in 2019. A cross sectional study conducted on 408 students aged 13-18 year from both sexes with different socioeconomic status through convenience sampling method. Anthropometric characteristics were measured to determine BMI for Age categories based on the WHO protocol. Visual analog scale (VAS) was used to assess participants' perceived satiety when faced to images of different plate's size and color with the same food volume. SPSS 21 was used to statistical analyze. 41.2% of student were on >85th percentile of BMI for age. Mean of score of VAS for medium red plate was significantly lower than medium and large white plates in both sexes (P<0.001), while mean of score of VAS for small white plate was significantly lower than large white plates only in girls (P<0.001). The adolescents who were on >85th percentile of BMI for age, gave higher score to large white plate than medium white plate and to medium white plate than medium red plate, significantly (P<0.001), while the scores given by the adolescent on 5th percentile of BMI, were not significant. Considering dramatic trend of obesity in adolescents in Iran, there is an urgent need to make supportive policies. Manipulating food containers seems to be an effective and simple approach to control feeling satiety. It may be a cost-effective approach to prevent obesity in adolescents before progressing to adulthood.

The outer membrane proteins based seroprevalence strategy for Brucella ovis natural infection in sheep.

The diagnosis of brucellosis largely relies on tiger red plate agglutination test (RBPT). However, it is difficult to distinguish between natural infection antibody positive and vaccination antibody positive, nevertheless, the identification of specific Brucella species natural infection. Here, we analyzed the structure of main outer membrane proteins (OMPs), OMP25 and OMP31 from Brucella ovis (B. ovis) and Brucella melitensis (B. melitensis), which are the main pathogens of sheep brucellosis, and found the OMP25 and OMP31 could be used as the differential antigens for B. ovis and B. melitensis antibody. Then we expressed the OMP25 from B. ovis (OMP25o) and OMP31 from B. melitensis (OMP31m). They have equally efficiency in antibody detection of vaccinated sheep serum, consistent with the RBPT results. However, through epidemiological investigations, we found some RBPT positive samples were negative by the OMP31m based serum antibody detection, but these samples gave positive results by the OMP25o. We verified these OMP31m negative but OMP25o positive samples by B. ovis and B. melitensis specific primers based PCR detection, and all these samples were B. melitensis negative. However, four out of six samples are B. ovis positive. These results showed that we could use the OMP25o and OMP31m to diagnose sheep brucellosis antibody, especially to discriminate the infection of the B. ovis. Currently, China has not yet approved a vaccine based on B. ovis and B. ovis positive samples should be naturally infected. There should be some implicit transmission of B. ovis in Jilin province. Further epidemiological investigation should be conducted to monitor the B. ovis natural infection.

Characterisation of key genotypic and phenotypic traits of clinical cystic fibrosis Staphylococcus aureus isolates.

Introduction. One third of people with CF in the UK are co-infected by both Staphylococcus aureus and Pseudomonas aeruginosa. Chronic bacterial infection in CF contributes to the gradual destruction of lung tissue, and eventually respiratory failure in this group.Gap Statement. The contribution of S. aureus to cystic fibrosis (CF) lung decline in the presence or absence of P. aeruginosa is unclear. Defining the molecular and phenotypic characteristics of a range of S. aureus clinical isolates will help further understand its pathogenic capabilities.Aim. Our objective was to use molecular and phenotypic tools to characterise twenty-five clinical S. aureus isolates collected from mono- and coinfection with P. aeruginosa from people with CF at the Royal Victoria Infirmary, Newcastle upon Tyne.Methodology. Genomic DNA was extracted and sequenced. Multilocus sequence typing was used to construct phylogeny from the seven housekeeping genes. A pangenome was calculated using Roary, and cluster of Orthologous groups were assigned using eggNOG-mapper which were used to determine differences within core, accessory, and unique genomes. Characterisation of sequence type, clonal complex, agr and spa types was carried out using PubMLST, eBURST, AgrVATE and spaTyper, respectively. Antibiotic resistance was determined using Kirby-Bauer disc diffusion tests. Phenotypic testing of haemolysis was carried out using ovine red blood cell agar plates and mucoid phenotypes visualised using Congo red agar.Results. Clinical strains clustered closely based on agr type, sequence type and clonal complex. COG analysis revealed statistically significant enrichment of COG families between core, accessory and unique pangenome groups. The unique genome was significantly enriched for replication, recombination and repair, and defence mechanisms. The presence of known virulence genes and toxins were high within this group, and unique genes were identified in 11 strains. Strains which were isolated from the same patient all surpassed average nucleotide identity thresholds, however, differed in phenotypic traits. Antimicrobial resistance to macrolides was significantly higher in the coinfection group.Conclusion. There is huge variation in genetic and phenotypic capabilities of S. aureus strains. Further studies on how these may differ in relation to other species in the CF lung may give insight into inter-species interactions.

The Dynamic of Red Plate Bank's Financial Performance Before and During the Pandemic

The COVID-19 pandemic has disrupted business activities, including the banking industry. The Indonesian State Bank (BNI) might face the same challenges as other banks. However, as a well-established red plate bank, the dynamic of this bank needs to be further investigated to show how the pandemic affects its financial performance. The main objective of this study is to provide empirical evidence on whether the COVID-19 pandemic affects the financial performance of the red plate bank. In doing so, the current researchers conducted a comparative analysis using paired sample t-tests. Time series data based on BNI's quarterly financial reports from the first quarter of 2017 to the fourth quarter of 2022 were collected through documentation. The data were partitioned into two groups, which were data before the pandemic and during the pandemic. The paired sample t-test results show that, in general, there is no statistical difference in BNI's financial performance before and during the pandemic. The finding confirmed that, as a red plate bank, BNI is a well-established bank with a sound financial state regardless of the pandemic.

Study of spatter net forming mechanism and penetration mode under flexible ring mode laser welding

Flexible ring mode (FRM) laser technology can generate different powers by adjusting the power ratio of the inner and outer rings, and has great potential for welding copper and its alloys with high reflectivity. This paper used a high-speed photographic camera to monitor the behavior and spatter-forming process of molten pool on the front of red copper plate. The spattering behavior in different penetration modes and net forming mechanisms under FRM are revealed. The results show that full penetration causes the high-temperature vapor to escape from the upper and lower openings. More energy is absorbed by the molten pool and keyhole in the semi-penetration mode, forming an expansion zone and increasing the pool's instability. The outer ring laser of FRM reduces the temperature gradient, which can lower the surface tension gradient, making the flow of the molten pool smoother and the height and formation times of the liquid column lower and less, thereby reducing the spatter. Moreover, FRM laser produces a larger and more stable keyhole, making the escape of metal vapor easier and minimizing the kinetic energy. The reasons above bring the sound result of high yield rate, improved by 75%, comparing with pure Gaussian laser. This paper provides theoretical guidance for engineering researchers to understand the role of shaping laser beams in the welding of highly reflective materials.