•The ferrocene group decorated nano-organo SiO2–Al2O3 as a novel adsorbent.•The application of nano-adsorbent was studied to remove methyl orange.•It effectively removes 85% methyl orange from ...contaminated water under 25min.•The novel nano-adsorbent was very stable and easily separated from the purified water.
In this study, the application of a functional ferrocene (ferrocenecarboxaldehyde) firmly heterogenized over a modified nano-size SiO2–Al2O3 mixed-oxides was reported as a novel adsorbent for the removal of methyl orange from aqueous solution. SiO2–Al2O3 mixed-oxides was functionalized with 3-aminopropyl-triethoxysilane (3-APTES) group and ferrocenecarboxaldehyde covalently linked on this organo-functionalized SiO2–Al2O3 mixed-oxides support. The synthesized materials were characterized by FT-IR spectroscopy, UV–vis, CHN elemental analysis, BET, TGA, ICP-MS, TEM, and XPS. The contact time to obtain equilibrium for maximum adsorption was 50min. XPS of Fe ions evidenced that most of the active sites of the nano-adsorbent is in the form of Fe3+ ions at the surface. The heterogeneous Fe3+ ions were found to be effective adsorbent for the removal of dyes from solution. The adsorption of methyl orange ions has been studied in terms of pseudo-first-order and pseudo-second-order kinetics, and the Freundlich, Langmuir, and Langmuir–Freundlich isotherm models have also been applied to the equilibrium adsorption data. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model.
Road traffic emissions are often considered the main source of ultrafine particles (UFP, diameter smaller than 100 nm) in urban environments. However, recent studies worldwide have shown that - in ...high-insolation urban regions at least - new particle formation events can also contribute to UFP. In order to quantify such events we systematically studied three cities located in predominantly sunny environments: Barcelona (Spain), Madrid (Spain) and Brisbane (Australia). Three long-term data sets (1-2 years) of fine and ultrafine particle number size distributions (measured by SMPS, Scanning Mobility Particle Sizer) were analysed. Compared to total particle number concentrations, aerosol size distributions offer far more information on the type, origin and atmospheric evolution of the particles. By applying k-means clustering analysis, we categorized the collected aerosol size distributions into three main categories: "Traffic" (prevailing 44-63% of the time), "Nucleation" (14-19%) and "Background pollution and Specific cases" (7-22%). Measurements from Rome (Italy) and Los Angeles (USA) were also included to complement the study. The daily variation of the average UFP concentrations for a typical nucleation day at each site revealed a similar pattern for all cities, with three distinct particle bursts. A morning and an evening spike reflected traffic rush hours, whereas a third one at midday showed nucleation events. The photochemically nucleated particles' burst lasted 1-4 h, reaching sizes of 30-40 nm. On average, the occurrence of particle size spectra dominated by nucleation events was 16% of the time, showing the importance of this process as a source of UFP in urban environments exposed to high solar radiation. Nucleation events lasting for 2 h or more occurred on 55% of the days, this extending to > 4 h in 28% of the days, demonstrating that atmospheric conditions in urban environments are not favourable to the growth of photochemically nucleated particles. In summary, although traffic remains the main source of UFP in urban areas, in developed countries with high insolation urban nucleation events are also a main source of UFP. If traffic-related particle concentrations are reduced in the future, nucleation events will likely increase in urban areas, due to the reduced urban condensation sinks.
•Considering reliability of connecting links between facilities.•Calculating the failure probability of connecting links by using a spatial statistical model.•Assuming failure of ...bio-refineries.•Considering the effect of risk-pooling under supply disruptions.•Presenting encoding and decoding procedures for representing solutions.
Bio-fuel is one of the most important alternatives to fossil fuels due to energy shortages. The bio-fuel is derived from biomass that is obtained from agricultural products such as plant debris. In addition, the supply chain is affected by risks which are due to several reasons such as economic, natural phenomena, political and etc. The occurrence of such events can cause disruption in supply chain which can significantly increase the total supply chain costs and also prevent serve to customers. Reliability is involved the capability of a network to achieve an anticipated process such as ``communication". Analysis of network reliability has acknowledged significant consideration and is consequently broadly studied to forecast and avoid any network failure. In order to distribute bio-fuel to the customers, designing a reliable and sustainable bio-fuel supply chain is very importance. Thus a growth in bio-fuel production demonstrates the requirement for establishing an effective and reliable network of chain that not only accomplishes sound under regular circumstances nevertheless restricted risk under various unanticipated disruption situations. This paper presents mathematical model to design an efficient bio-fuel supply chain network at pre-disaster stage that considering failure in the connecting links between the facilities. In which the probability of failure of the links is forecasted by a spatial statistic approach and also due to the fact that disasters can cause disruptions in bio-refineries, leads to use the risk-pooling effect in order to reduce total costs. In order to solve the proposed mathematical model, two meta-heuristic algorithms containing genetic algorithm (GA) and bat algorithm (BA) are utilized. The results show that by increasing the reliability and improvement of connecting links between facilities and considering the risk-pooling effect on disrupted bio-refineries, the total costs of supply chain can be considerably reduced.
German chamomile is an important essential oil plant that has adaptability to a wide range of climates and soils. Methyl jasmonate (MJ) is a plant growth regulator that involves in many morphological ...and physiological processes and has a role in defense systems of plants under stress conditions. Here, a pot-culture study was undertaken to investigate the possible role of MJ treatment on the growth and different chemical constituents of German chamomile plants subjected to salinity stress. The aim was to determine whether MJ could protect chamomile production against salinity and whether this protection was associated with regulation of antioxidant enzymes. Our results show that treatment of chamomile plants with 75 µM MJ leads to increases in plant growth in terms of flower, straw and root dry weights. The photosynthetic rate concomitantly with membrane stability index, potassium content, as well as free proline content was markedly increased. In addition, the quercetin content was increased significantly in flowers. Moreover, the application of the investigated 75 μM MJ significantly improved enzyme activities in terms of catalase, peroxidase and ascorbate peroxidase activities. Sodium and proline contents were also measured and finally, effects of MJ and salinity interactions on all characteristics as well as relationship of antioxidant enzymes activity with proline content were investigated. As a conclusion, treating chamomile plants with 75 μM MJ could alleviate the harmful effects of salinity stress.
This study was done to find exopolysaccharide (EPS)‐producing lactic acid bacteria (LAB) against foodborne pathogens. Isolated LAB were screened to find the ones with the ability to produce ...antibacterial EPS against foodborne pathogens. Among tested EPSs, EPS of AS20(1) isolate showed inhibitory effects on the growth of Listeria monocytogenes (MIC = 0·935 mg ml−1, MBC = 0·935 mg ml−1), Yersinia enterocolitica (MIC = 12·5 mg ml−1, MBC = 50 mg ml−1) and Bacillus cereus (MIC = 6·25 mg ml−1, MBC = 12·5 mg ml−1). According to 16S rRNA sequencing, AS20(1) showed the closest similarity to Lacticaseibacillus paracasei (100%). This antibacterial EPS showed negligible toxicity (4·4%–5·2%) against red blood cells. Lacticaseibacillus paracasei AS20(1) showed probiotic properties, including high acid resistance, hydrophobicity (47·5%), autoaggregation and coaggregation with foodborne pathogens. Also, L. paracasei AS20(1) showed no haemolysis activity and antibiotic resistance. Characterization of antibacterial EPS revealed that it is a heteropolysaccharide with various functional groups, amorphous structure, and smooth surface, sheet and compact structure, which can be suitable for food packaging. L. paracasei AS20(1) and its antimicrobial EPS can be used to make functional food.
Significance and Impact of the Study: In the current study, Lacticaseibacillus paracasei AS20(1) was introduced as an antibacterial EPS‐producing lactic acid bacterium with probiotic potential. Lacticaseibacillus paracasei AS20(1) and its EPS with specific bactericidal activity towards pathogens have potential in the food industry.
In recent years, due to the controllable mechanical properties and degradation rate, calcium silicates such as akermanite (Ca
MgSi
O
) with Ca-Mg and Si- containing bio-ceramics have received much ...more attention. In addition, the piezoelectric effect plays an important role in bone growth, remodeling and defect healing. To achieve our objective, the porous bioactive nano-composite with a suitable piezoelectric coefficient was fabricated by the freeze-casting technique from the barium titanate and nano-akermanite (BT/nAK) suspension. The highest d
of 4pC/N was obtained for BT90/nAK10. The compressive strength and porosity were for BT75/nAK25 and BT60/nAK40 at the highest level, respectively. The average pore channel diameter was 41 for BT75/nAK25. Interestingly enough, the inter-connected pore channel was observed in the SEM images. There was no detectable transformation phase in the XRD pattern for the BT/nAK composites. The manipulation flexibility of this method indicated the potential for the customized needs in the application of bone substitutes. An ((3-4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide)) MTT assay indicated that the obtained scaffolds have no cytotoxic effects on the human bone marrow mesenchymal stem cells.
Aim
Vascular calcification (VC) is a significant pathological process in some life‐threatening diseases. Several pathological mechanisms, including transdifferentiation of vascular smooth muscle ...cells to osteoblast‐like cells and apoptosis are involved in VC. Compounds with an inhibitory effect on these processes are potentially efficient medications. In consideration of the multiple biological activities of Actinobacteria, this research was aimed at finding anti‐VC metabolite‐producing Actinobacteria.
Methods and Results
After the isolation and identification of Actinobacteria, the effect of their fermentation broth extracts on the apoptosis rate was measured using various methods, for example, ethidium bromide/acridine orange staining, DNA laddering and diphenylamine assays. The effect of the most effective fermentation broth extract of Actinobacteria (FBEA) on the mRNA expression of runt‐related transcription factor 2 (Runx2) and osteopontin (OPN) was examined. Finally, the most effective FBEA was fractionated and the chemical composition of anti‐VC fractions was analysed using GC‐MS. Various VC inhibition rates were observed in the tested FBEA (20 μg ml−1; 17·9–60·15%). The inhibition of DNA fragmentation was 7–48%. The FBE with the greatest anticalcification activity belonged to Kribbella sp. UTMC 267 and, according to 16S rRNA analysis, Kribbella sancticallisti with a similarity of 98·53% is its nearest neighbour. The FBE of Kribbella sp. UTMC 267 reduced Runx2 mRNA expression by 2·95‐fold and OPN mRNA expression by 28·57‐fold, both of which are considered significant (P < 0·05). Finally, GC‐MS analysis showed the existence of potent anti‐oxidative and anti‐inflammation agents in FBE of Kribbella sp. UTMC 267.
Conclusions
Actinobacterial metabolites can provide a new strategy for treating VC diseases by reducing the expression of osteogenic genes, the apoptosis rate and oxidative stress.
Significance and Impact of the Study
This study highlights the therapeutic potential of Kribbella sp. metabolites and Actinobacteria as a new natural source for drug discovery programs in the nonantibiotic bioactivity field.
All roads can lead to surgery Motter, D.; Salimi, F.
Annals of medicine and surgery,
01/2022, Letnik:
73
Journal Article
Recenzirano
Odprti dostop
Pursuing a career in surgery is a rigorous process that demands commitment and hard work. Surgeons in the United Kingdom must go overcome a myriad of competitive stages prior to becoming a ...consultant. In the United Kingdom, the most common pathway to become a surgeon is via the ‘direct route’ which encompasses completing multiple training programs, namely, the Foundation Program, followed by Core Surgical Training, and then onto Higher Speciality Training, with the aim of obtaining the Certificate of Completion of Training (CCT). More recently, certain specialities have introduced the ‘Improving Surgical Training’ (IST) pathway. IST is a competence-based, run through surgical program that was introduced by the Royal College of Surgeons of England (RCS) and Health Education England (HEE). “The pilot trials improvements in the quality of training, a better balance between service and training for trainees, and professionalisation of the role of the surgical trainers” 1. However, there are alternative pathways that have been designed for those who prefer a different route to training or have been unsuccessful during the selection stages. These pathways are not well-advertised, but with the competitive rates now higher than before, it is becoming a more attractive pathway for junior doctors, hence the increasing the demand for clearer instructions on potential routes for aspiring surgeons.
•Core surgical training in the UK has become more competitive over the last few years.•There are different pathways to becoming a surgeon.•We look at different routes available to junior trainees.•We encourage trainees who want flexibility at work to consider the alternative core training pathway.
COVID-19 pandemic and restrictive public health measures due to it can have many effects on physical activity. Our study aimed to compare the levels of physical activity levels (expressed as ...MET–minute/week), among Qom city (Iran) adults in pre and during the COVID-19 pandemic (January 2020 and 20 to 29 May 2020, respectively). 670 adults were included in this study and grouped based on age and gender. The short-form International physical activity questionnaire (IPAQ, SF) was distributed to the participants through an online survey. The Wilcoxon signed-rank test was used for statistical analyses. The present study showed that the level of physical activity decreased significantly during COVID-19 compared to pre-COVID-19 in both sexes and age groups (p < 0.001). Also, this study found that a total of 78% of the participants did not meet the physical activity guidelines during COVID-19 in Iran. Our results indicate the necessity to consider an integrated and comprehensive approach to reduce the inactivity caused by COVID-19.
Infectious disease; Occupational health; Physical activity; Physiology; Public health; Quality of life; COVID-19; Lifestyle.
Long-term measurements of particle number size distribution (PNSD) produce a very large number of observations and their analysis requires an efficient approach in order to produce results in the ...least possible time and with maximum accuracy. Clustering techniques are a family of sophisticated methods that have been recently employed to analyse PNSD data; however, very little information is available comparing the performance of different clustering techniques on PNSD data. This study aims to apply several clustering techniques (i.e. K means, PAM, CLARA and SOM) to PNSD data, in order to identify and apply the optimum technique to PNSD data measured at 25 sites across Brisbane, Australia. A new method, based on the Generalised Additive Model (GAM) with a basis of penalised B-splines, was proposed to parameterise the PNSD data and the temporal weight of each cluster was also estimated using the GAM. In addition, each cluster was associated with its possible source based on the results of this parameterisation, together with the characteristics of each cluster. The performances of four clustering techniques were compared using the Dunn index and Silhouette width validation values and the K means technique was found to have the highest performance, with five clusters being the optimum. Therefore, five clusters were found within the data using the K means technique. The diurnal occurrence of each cluster was used together with other air quality parameters, temporal trends and the physical properties of each cluster, in order to attribute each cluster to its source and origin. The five clusters were attributed to three major sources and origins, including regional background particles, photochemically induced nucleated particles and vehicle generated particles. Overall, clustering was found to be an effective technique for attributing each particle size spectrum to its source and the GAM was suitable to parameterise the PNSD data. These two techniques can help researchers immensely in analysing PNSD data for characterisation and source apportionment purposes.
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