ABSTRACT
The escalating presence of per- and polyfluoroalkyl substances (PFAS) in drinking water poses urgent public health concerns, necessitating effective removal. This study presents a groundbreaking approach, using viologen to synthesize covalent organic framework nanospheres: MELEM-COF and MEL-COF. Characterized by highly crystalline features, these nanospheres exhibit exceptional affinity for diverse anionic PFAS compounds, achieving simultaneous removal of multiple contaminants within 30 min. Investigating six anionic PFAS compounds, MEL- and MELEM-COFs achieved 90.0-99.0% removal efficiency. The integrated analysis unveils the synergistic contributions of COF morphology and functional properties to PFAS adsorption. Notably, MELEM-COF, with cationic surfaces, exploits electrostatic and dipole interactions, with a 2500 mg g-1 adsorption capacity-surpassing all reported COFs to date. MELEM-COF exhibits rapid exchange kinetics, reaching equilibrium within 30 min. These findings deepen the understanding of COF materials and promise avenues for refining COF-based adsorption strategies.
ABSTRACT
Clear emulsions are used as flavor carriers by the beverage industry because of their favorable optical properties. A transparent microemulsion with small droplets requires a high concentration of surfactants, and is often non-dilutable, posing a significant challenge to their application in the food industry. The formation of dilutable microemulsions by modulating the compatibility of oil composition and co-solvents was studied. While single-fold lemon oil exhibited poor loading capacity overall, no precipitation occurred due to the stronger interaction between monoterpenes and sucrose monopalmitate (SMP). Conversely, emulsification of five-fold lemon oil with 20 % ethanol demonstrated a higher loading capacity and a stronger dilution stability than other lemon oils. This is likely due to the balanced composition of surface-active monoterpenes and other components in five-fold lemon oil which facilitated the effective use of micellar space and aided in the retention of both surfactants and co-solvents post-dilution. The emulsification of higher-folded lemon oil, however, was favored by the use of propylene glycol as a surfactant exhibiting stronger dilution stability than ethanol, though it required twice as much co-solvent. The high concentration of surface-active monoterpene in the lower-folded lemon oils competes with propylene glycol for interfacial incorporation. This study demonstrated that co-solvents and oil composition play interactive roles in producing dilutable optically clear emulsions, and it provides a blueprint for the food industry to design colloidal systems using a minimum of surfactants.
Subject(s)
Emulsions , Plant Oils , Solvents , Surface-Active Agents , Emulsions/chemistry , Plant Oils/chemistry , Solvents/chemistry , Surface-Active Agents/chemistry , Particle Size , Citrus/chemistry , Ethanol/chemistryABSTRACT
The idea of building large structures from small building blocks has had a long history in the human imagination, from the beautifully intricate shells assembled from silica by unicellular algae to the Egyptian pyramids built from stone. Carrying this idea into the food industry has important implications. Here, we introduce a Pickering emulsion platform for building superstructures like hollow cages and sheets using starch granules as building blocks. In food, these superstructures occupy up to six times more space than their constituent parts, thereby delivering a viscosity greater by an order of magnitude than unstructured starch. To achieve this higher viscosity, they use an alternative superstructure mechanism as opposed to the classic swelling mechanism of individual particles. These super-thickeners may reduce calories, cut production costs, and stretch the global food supply, demonstrating how we can design the future by playing with our food.
Subject(s)
Food , Starch , Humans , Starch/chemistry , EmulsionsABSTRACT
Solid phase adsorbents with high removal affinity for per- and polyfluoroalkyl substances (PFAS) in aqueous environments are sought. We report the synthesis and investigation of COF-I, a new covalent organic framework (COF) with a good affinity for PFAS adsorption. COF-I was synthesized by the condensation reaction between 2,4,6-trimethyl-1,3,5-triazine and 2,3-dimethoxyterephthaldehyde and fully characterized. In addition to the high crystallinity and surface area, COF-I showed high hydrolytic and thermal stability. Further, we converted its hydrophobic surface to a hydrophilic surface by converting the ortho-methoxy groups to hydroxyl derivatives and produced a new hydrophilic olefin-linked two-dimensional (2D) COF. We experimentally measured the crystallinity of both COFs by X-ray diffraction and used atomistic simulations coupled with cross-polarization/magic angle spinning solid-state nuclear magnetic resonance (CP/MAS ssNMR) to determine the relative amounts of AA-stacking and AB-stacking present. COF-I, with its hydrophobic surface and methoxy groups in the ortho positions, showed the best PFAS adsorption. COF-I reduced the concentration of perfluorooctanoic acid from 20 to 0.069 µg L-1 and to 0.052 µg L-1 for perfluorooctanesulfonic acid. These amounts are lower than the U.S. Environmental Protection Agency advisory level (0.070 µg L-1). High efficiency, fast kinetic adsorption, and reusability of COF-I are advantages of COF-I for PFAS removal from water.
ABSTRACT
PURPOSE: The aim of this study was development and evaluation of a fully automated tool for the detection and segmentation of mPCa lesions in whole-body [68Ga]Ga-PSMA-11 PET scans by using a nnU-Net framework. METHODS: In this multicenter study, a cohort of 412 patients from three different center with all indication of PCa who underwent [68Ga]Ga-PSMA-11 PET/CT were enrolled. Two hundred cases of center 1 dataset were used for training the model. A fully 3D convolutional neural network (CNN) is proposed which is based on the self-configuring nnU-Net framework. A subset of center 1 dataset and cases of center 2 and center 3 were used for testing of model. The performance of the segmentation pipeline that was developed was evaluated by comparing the fully automatic segmentation mask with the manual segmentation of the corresponding internal and external test sets in three levels including patient-level scan classification, lesion-level detection, and voxel-level segmentation. In addition, for comparison of PET-derived quantitative biomarkers between automated and manual segmentation, whole-body PSMA tumor volume (PSMA-TV) and total lesions PSMA uptake (TL-PSMA) were calculated. RESULTS: In terms of patient-level classification, the model achieved an accuracy of 83%, sensitivity of 92%, PPV of 77%, and NPV of 91% for the internal testing set. For lesion-level detection, the model achieved an accuracy of 87-94%, sensitivity of 88-95%, PPV of 98-100%, and F1-score of 93-97% for all testing sets. For voxel-level segmentation, the automated method achieved average values of 65-70% for DSC, 72-79% for PPV, 53-58% for IoU, and 62-73% for sensitivity in all testing sets. In the evaluation of volumetric parameters, there was a strong correlation between the manual and automated measurements of PSMA-TV and TL-PSMA for all centers. CONCLUSIONS: The deep learning networks presented here offer promising solutions for automatically segmenting malignant lesions in prostate cancer patients using [68Ga]Ga-PSMA PET. These networks achieve a high level of accuracy in whole-body segmentation, as measured by the DSC and PPV at the voxel level. The resulting segmentations can be used for extraction of PET-derived quantitative biomarkers and utilized for treatment response assessment and radiomic studies.
Subject(s)
Gallium Isotopes , Gallium Radioisotopes , Prostatic Neoplasms , Male , Humans , Positron Emission Tomography Computed Tomography/methods , Prostatic Neoplasms/pathology , Neural Networks, Computer , BiomarkersABSTRACT
There have been inconsistent reports regarding the association between dietary acid load and Metabolic Syndrome (MetS). We aimed to investigate the association between dietary acid load and MetS in an Iranian adult population. In this cross-sectional study, 1945 participants aged 35-65 years were recruited from MASHAD cohort study. Dietary intakes were assessed using a 24-h dietary recall. Diet-based acidity was assessed as the net endogenous acid production (NEAP), potential renal acid load (PRAL), and dietary acid load (DAL). To define MetS, the International Diabetes Federation (IDF) criteria were used. Multivariable logistic regression models were applied to determine the association between diet-based acid load scores and MetS. Participants' mean age and BMI were 47.13 ± 7.78 years and 27.57 ± 4.48 kg/m2, respectively. Around 57% of the population was female. Overall, 31.9% had MetS. According to the full-adjusted model, there was a significant association between higher quartiles of PRAL, NEAP, and DAL and MetS (Q4 PRAL; OR (95%CI) 1.42(1.05-1.91), Q4 NEAP; OR (95%CI) 1.48(1.11-1.98), Q4 DAL; OR (95%CI) 1.44(1.05-1.91)). This study showed a significant positive association between different dietary acid load indicators (PRAL, NEAP, and DAL) and odds of MetS among Iranian adults.
Subject(s)
Metabolic Syndrome , Adult , Humans , Female , Metabolic Syndrome/epidemiology , Metabolic Syndrome/etiology , Risk Factors , Cross-Sectional Studies , Cohort Studies , Iran/epidemiology , Diet/adverse effects , Acids/metabolismABSTRACT
Lactoferrin (LF), the main iron-binding protein of milk, has important nutritional, biological, and pharmaceutical properties. It is an essential nutritional component of newborn diets and also for adult health. Small amounts of lactoferrin can be found in whey, a nutritionally and biologically useful byproduct of the dairy industry. Although the amount of lactoferrin in whey is less than that in other sources like milk and bovine colostrum, the extraction of LF from this underused source has many economic and environmental benefits. The most common technique for the isolation of LF from dairy products is the use of cation-exchange resins. Here, we present the synthesis of a strong cation-exchange resin for the extraction of high-purity lactoferrin from whey. This resin was synthesized by inverse suspension copolymerization of aqueous solutions of sodium 2-acrylamido-2-methyl-1-propanesulfonate and N,N-methylenebisacrylamide in corn oil. The adsorption efficiency of this resin showed selective extraction of lactoferrin from four different whey sources. The adsorption efficiency of lactoferrin from these whey samples ranged from 93.8 to 97.4%.
ABSTRACT
The present work was carried out to remove phenol from aqueous medium using a photocatalytic process with superparamagnetic iron oxide nanoparticles (Fe3O4) called SPIONs. The photocatalytic process was optimized using a central composite design based on the response surface methodology. The effects of pH (3-7), UV/SPION nanoparticles ratio (1-3), contact time (30-90 minutes), and initial phenol concentration (20-80 mg L-1) on the photocatalytic process were investigated. The interaction of the process parameters and their optimal conditions were determined using CCD. The statistical data were analyzed using a one-way analysis of variance. We developed a quadratic model using a central composite design to indicate the photocatalyst impact on the decomposition of phenol. There was a close similarity between the empirical values gained for the phenol content and the predicted response values. Considering the design, optimum values of pH, phenol concentration, UV/SPION ratio, and contact time were determined to be 3, 80 mg L-1, 3, and 60 min, respectively; 94.9% of phenol was eliminated under the mentioned conditions. Since high values were obtained for the adjusted R2 (0.9786) and determination coefficient (R2 = 0.9875), the response surface methodology can describe the phenol removal by the use of the photocatalytic process. According to the one-way analysis of variance results, the quadratic model obtained by RSM is statistically significant for removing phenol. The recyclability of 92% after four consecutive cycles indicates the excellent stability of the photocatalyst for practical applications. Our research findings indicate that it is possible to employ response surface methodology as a helpful tool to optimize and modify process parameters for maximizing phenol removal from aqueous solutions and photocatalytic processes using SPIONs.
ABSTRACT
The existence of potentially toxic elements (PTEs) in water bodies has posed a menace to human health. Thus, water resources should be protected from PTEs, and their effect on the exposed population should be investigated. In the present investigation, the concentrations of PTEs such as lead (Pb), mercury (Hg), manganese (Mn), and iron(Fe) in the drinking water of Shiraz, Iran, were determined for the first time. In addition, hazard quotient, hazard index, cancer risk, and sensitivity analysis were applied to estimate the noncarcinogenic and carcinogenic impacts of Pb, Hg, Mn, and Fe on exposed children and adults through ingestion. The mean concentrations (µg/L) of Pb, Hg, Mn, and Fe were 0.36, 0.32, 2.28, and 8.72, respectively, in winter and 0.50, 0.20, 0.55, and 10.36, respectively, in summer. The results displayed that Fe concentration was more than the other PTEs. PTE concentrations were lower than the standard values of the Environment Protection Agency and World Health Organization. Values of the degree of contamination and heavy metal pollution index for lead, mercury, manganese, and iron were significantly low (< 1) and excellent (< 50), respectively. Based on the Spearman rank correlation analysis, positive and negative relationships were observed in the present study. The observations of the health risk assessment demonstrated that mercury, lead, iron, and manganese had an acceptable level of noncarcinogenic harmful health risk in exposed children and adults (hazard quotients < 1 and hazard index < 1). The carcinogenic risk of lead was low (< E - 06), which can be neglected. Monte Carlo simulation showed that water intake rate and mercury concentration were the most critical parameters in the hazard index for children and adults. Lead concentration was also the most crucial factor in the cancer risk analysis. The results of the present study proved that the drinking water of Shiraz is safe and healthy and can be confidently consumed by people.
Subject(s)
Drinking Water , Mercury , Metals, Heavy , Neoplasms , Soil Pollutants , Adult , Child , Humans , Lead/analysis , Drinking Water/analysis , Manganese/analysis , Iran , Environmental Monitoring/methods , Metals, Heavy/analysis , Mercury/analysis , Iron/analysis , Risk Assessment/methods , Carcinogens/analysis , Carcinogenesis , Soil Pollutants/analysisABSTRACT
Catechin is a flavonoid naturally present in numerous dietary products and fruits (e.g., apples, berries, grape seeds, kiwis, green tea, red wine, etc.) and has previously been shown to be an antioxidant and beneficial for the gut microbiome. To further enhance the health benefits, bioavailability, and stability of catechin, we synthesized and characterized catechin pentaacetate and catechin pentabutanoate as two new ester derivatives of catechin. Catechin and its derivatives were assessed in vivo via intra-amniotic administration (Gallus gallus), with the following treatment groups: (1) non-injected (control); (2) deionized H2O (control); (3) Tween (0.004 mg/mL dose); (4) inulin (50 mg/mL dose); (5) Catechin (6.2 mg/mL dose); (6) Catechin pentaacetate (10 mg/mL dose); and (7) Catechin pentabutanoate (12.8 mg/mL dose). The effects on physiological markers associated with brush border membrane morphology, intestinal bacterial populations, and duodenal gene expression of key proteins were investigated. Compared to the controls, our results demonstrated a significant (p < 0.05) decrease in Clostridium genera and E. coli species density with catechin and its synthetic derivative exposure. Furthermore, catechin and its derivatives decreased iron and zinc transporter (Ferroportin and ZnT1, respectively) gene expression in the duodenum compared to the controls. In conclusion, catechin and its synthetic derivatives have the potential to improve intestinal morphology and functionality and positively modulate the microbiome.
Subject(s)
Catechin , Chickens , Animals , Antioxidants/metabolism , Antioxidants/pharmacology , Bacteria/metabolism , Catechin/metabolism , Catechin/pharmacology , Chickens/metabolism , Escherichia coli/metabolism , Esters/metabolism , Esters/pharmacology , Inulin/metabolism , Inulin/pharmacology , Iron/metabolism , Microvilli , Polysorbates/pharmacology , Tea/metabolismABSTRACT
This study aims at investigating the quality of drinking water and evaluating the non-carcinogenic risk of fluoride and nitrate ions in drinking water, and fluoride in tea in Zarrin Dasht, Iran. We focus on tea since it is the most popular drink among Iranian people and in the study region. We collected and analyzed 23 drinking water samples and 23 tea samples from different locations in the study region. Based on the water quality index, the consumed drinking water does not have a good quality in most Zarrin Dasht areas. Accordingly, the water quality index (WQI) is poor and very poor in 70% and 13% of the water samples, respectively. The average fluoride concentration of the tea samples is 2.71 mg/L. The mean values of Fluoride Hazard Index (HIfluoride) are 3.77, 2.77, and 2.33 for children, teenagers, and adults, respectively, which are higher than the safe limit of 1. The Nitrate Hazard Index (HInitrate) is higher than the safe limit of 1 in 8.7% of the samples. The results of the Monte Carlo simulation demonstrate that HIfluoride and HInitrate are higher than 1 in all the groups, except for adults. According to the results of the sensitivity analysis, ingestion rate and body weight have a large effect on HIfluoride and HInitrate, but body weight is inversely associated with sensitivity. According to the Piper diagram, saline water is the predominant type in Zarrin Dasht. Besides, the results of the principal component analysis (PCA) show a high correlation between fluoride and pH, which could be related to the effect of pH on fluoride dissolution and ion exchange. Therefore, appropriate measures are recommended to be taken in order to reduce the amount of fluoride in the drinking water resources of this region. Reduction of tea consumption can also be considered an important factor in decreasing the amount of fluoride intake.
Subject(s)
Drinking Water , Groundwater , Water Pollutants, Chemical , Adolescent , Adult , Body Weight , Child , Drinking Water/analysis , Environmental Monitoring/methods , Fluorides/analysis , Groundwater/analysis , Humans , Iran , Nitrates , Risk Assessment , Tea , Water Pollutants, Chemical/analysis , Water QualityABSTRACT
Nicotinamide riboside (NR) acts as a nicotinamide adenine dinucleotide (NAD+) precursor where NR supplementation has previously been shown to be beneficial. Thus, we synthesized and characterized nicotinamide riboside tributyrate chloride (NRTBCl, water-soluble) and nicotinamide riboside trioleate chloride (NRTOCl, oil-soluble) as two new ester derivatives of nicotinamide riboside chloride (NRCl). NRCl and its derivatives were assessed in vivo, via intra-amniotic administration (Gallus gallus), with the following treatment groups: (1) non-injected (control); and injection of (2) deionized H2O (control); (3) NRCl (30 mg/mL dose); (4) NRTBCl (30 mg/mL dose); and (5) NRTOCl (30 mg/mL dose). Post-intervention, the effects on physiological markers associated with brush border membrane morphology, intestinal bacterial populations, and duodenal gene expression of key proteins were investigated. Although no significant changes were observed in average body weights, NRTBCl exposure increased average cecum weight. NR treatment significantly increased Clostridium and NRCl treatment resulted in increased populations of Bifidobacterium, Lactobacillus, and E. coli. Duodenal gene expression analysis revealed that NRCl, NRTBCl, and NRTOCl treatments upregulated the expression of ZnT1, MUC2, and IL6 compared to the controls, suggesting alterations in brush border membrane functionality. The administration of NRCl and its derivatives appears to trigger increased expression of brush border membrane digestive proteins, with added effects on the composition and function of cecal microbial populations. Additional research is now warranted to further elucidate the effects on inflammatory biomarkers and observe changes in the specific intestinal bacterial populations post introduction of NR and its derivatives.
Subject(s)
Chickens , Escherichia coli , Animals , Bacteria/metabolism , Chickens/metabolism , Chlorides/metabolism , Escherichia coli/metabolism , Microvilli , NAD , Niacinamide/analogs & derivatives , Pyridinium CompoundsABSTRACT
This paper proposes an adaptive fractional-order nonsingular terminal sliding mode (AFNTSMC) control scheme combined with the independent joint control approach for trajectory tracking of three-axis gimbal platforms (GPs) mounted on a moving vehicle subjected to external disturbances. To achieve accurate images taken by the camera mounted on the GP, the motions and vibrations of the vehicle must be isolated from the camera. Thus, precise mathematical modeling of a three-axis GP with considering the external disturbances is studied, such that the GP tracks the target accurately and holds the line of sight stationary. Various tests with different vehicle conditions are performed to collect the movement data to be considered as the desired input for the GP. Thanks to the utilization of AFNTSMC, fast convergence together with simultaneous accurate trajectory tracking and strong robustness can be ensured. Corresponding comparative simulation results validate the effectiveness of the theoretical design results and superiorities of the proposed method over the existing methods.
ABSTRACT
In the present work, we describe an efficient method for scalable synthesis and purification of 1,4-dihydronicotinamide riboside (NRH) from commercially available nicotinamide riboside chloride (NRCl) and in the presence of sodium dithionate as a reducing agent. NRH is industrially relevant as the most effective, synthetic NAD+ precursor. We demonstrated that solid phase synthesis cannot be used for the reduction of NRCl to NRH in high yield, whereas a reduction reaction in water at room temperature under anaerobic conditions is shown to be very effective, reaching a 55% isolation yield. For the first time, by using common column chromatography, we were able to highly purify this sensitive bio-compound with good yield. A series of identifications and analyses including HPLC, NMR, LC-MS, FTIR, and UV-vis spectroscopy were performed on the purified sample, confirming the structure of NRH as well as its purity to be 96%. Thermal analysis of NRH showed higher thermal stability compared to NRCl, and with two major weight losses, one at 218 °C and another at 805 °C. We also investigated the long term stability effects of temperature, pH, light, and oxygen (as air) on the NRH in aqueous solutions. Our results show that NRH can be oxidized in the presence of oxygen, and it hydrolyzed quickly in acidic conditions. It was also found that the degradation rate is lower under a N2 atmosphere, at lower temperatures, and under basic pH conditions.
ABSTRACT
Nicotinamide riboside chloride (NRCl) is an effective form of vitamin B3. However, it cannot be used in ready-to-drink (RTD) beverages or high-water activity foods because of its intrinsic instability in water. To address this issue, we synthesized nicotinamide riboside trioleate chloride (NRTOCl) as a new hydrophobic nicotinamide riboside (NR) derivative. Contrary to NRCl, NRTOCl is soluble in an oil phase. The results of stability studies showed that NRTOCl was much more stable than NRCl both in water and in oil-in-water emulsions at 25 °C and 35 °C. Finally, we evaluated the bioavailability of NRTOCl by studying its digestibility in simulated intestinal fluid. The results demonstrated that NRTOCl was partially digestible and released NR in the presence of porcine pancreatin in a simulated intestinal fluid. This study showed that NRTOCl has the potential to be used as an NR derivative in ready-to-drink (RTD) beverages and other foods and supplement applications.
Subject(s)
Niacinamide/analogs & derivatives , Niacinamide/chemical synthesis , Biological Availability , Body Fluids , Hydrolysis , Models, Biological , Molecular Structure , Niacinamide/chemistry , Niacinamide/pharmacokineticsABSTRACT
Carwash wastewater (CWW) is considered as an important source of either water pollution or water consumption. Therefore, its treatment is critical not only from the prevention of environmental contamination but also from the recycling of such high-volume water source. Unfortunately, the effective treatment of CWW is almost unknown, complex, and expensive. To overcome the former challenge, this study aimed to systematically review different technologies for CWW treatment. For this, a comprehensive literature survey was conducted and 48 research articles were found suitable to be included in the investigation. The included studies were of coagulation and adsorption (n = 5), membrane-based technologies (n = 15), and electrochemical (n = 11) and combined (n = 17) systems. This comprehensive review showed that the treatment methods of advanced filtration membrane techniques, electrical and chemical coagulation, and advanced oxidation processes can be effective in the removal of pollutants from carwash wastewater (CWW). The mining of different studies, however, showed that the combined methods are the most promising option in the remediation of such wastewater.
Subject(s)
Water Pollutants, Chemical , Water Purification , Adsorption , Oxidation-Reduction , Wastewater/analysisABSTRACT
BACKGROUND: Dust exposure at quarry mines is inevitable and can result in poor air quality. This research aimed to assess pulmonary symptoms and lung functions of dust-exposed workers at an iron-ore mine in eastern Iran. METHODS: An environmental cross-sectional study sampled 174 dust-exposed mine workers and 93 unexposed administrative employees as the reference group. A standardized questionnaire on respiratory symptoms was completed in accordance with recommendations of the American Thoracic Society(ATS). Calibrated spirometer measured Pulmonary Function Tests (PFTs). Data were analyzed via SPSS-21, integrating independent samples t-test, Chi-square and linear or logistic-regression models. RESULTS: There was no significant variation between dust-exposed and reference groups in terms of age, weight, height, work experience and the number of smokers (P>0.05). Mean levels of exposure to inhalable and respirable mineral-dust were 15.09±2.34 and 3.45±2.57 mg/m3 respectively. Pulmonary capacities of dust-exposed group were considerably decreased as compared to others (Forced Vital Capacity [FVC] 86.55±13.77 vs. 105.05±21.5; Forced Expiratory Volume in 1 second [FEV1] 88.06±16.8 vs. 105.81±21.55; FEV1/FVC 103.03±18.17 vs. 93.3±12.49; and Peak Expiratory Flow [PEF] 89.82±22.58 vs. 98.09±20.60) (P<0.001); with a higher prevalence of cough (P=0.041), wheezing (P=0.032), and dyspnea (P=0.035) among formers. Age along with exposure to respirable-dust significantly reduced FVC, FEV1 and FEV1/FVC. Cigarette consumption attenuated FVC and FEV1 on an average of 5 to 9 units. CONCLUSION: Controlled occupational dust-exposure is a definitive pre-requisite to reduce respiratory problems among quarry workers, with an explicit consideration towards mineral- mine workers. Modifiable accomplices like smoking and non-compliance of PPEs usage should be amicably resolved.
ABSTRACT
The aim of this study was to fabricate and characterize biodegradable polycaprolactone fumarate(PCLF)/gelatin-based nanocomposite incorporated with the 0, 5 and 10â¯wt% silicon and magnesium co-doped fluorapatite nanoparticles (Si-Mg-FA) membranes using electrospinning process for guided bone regeneration (GBR) and guided tissue regeneration (GTR) applications. Results demonstrated the formation of randomly-oriented and defect-free fibers with various fiber sizes depending on the Si-Mg-FA content. Moreover, incorporation of 5â¯wt% Si-Mg-FA significantly improved the mechanical strength (1.5times) compared to the mechanical strength of PCLF/gelatin membrane and nanocomposite with 10â¯wt% nanoparticles. There was no clear difference between degradation rate of PCLF/gelatin and PCLF/gelatin with 5â¯wt% nanoparticles at 7, 14 and 28â¯days of immersion in phosphate buffer saline while 10â¯wt% nanoparticles significantly increased biodegradation of PCLF/gelatin, and no cytotoxic effect of membranes was seen. Finally, scanning electron microscopy (SEM) micrographs of fibroblast cells cultured on the samples demonstrated that the cells were completely attached and spread on the surface of nanocomposites. In summary, PCLF/gelatin membranes consisting of 5â¯wt% Si-Mg-FA nanoparticles could provide appropriate mechanical and biological properties and fairly good degradation rate, making it appropriate for GTR/GBR applications.
Subject(s)
Apatites/chemistry , Gelatin/chemistry , Magnesium/chemistry , Nanocomposites/chemistry , Nanoparticles/chemistry , Polyesters/chemistry , Silicon/chemistryABSTRACT
Signal peptide (SP) is an important factor and biobrick in the production and secretion of recombinant proteins. The aim of this study was in silico and in vivo analysis of SPs effect on the production of recombinant glucose oxidase (GOX) in Yarrowia lipolytica. Several in silico softwares, namely SignalP4, Signal-CF, Phobius, WolfPsort 0.2, SOLpro and ProtParam, were used to analyse the potential of 15 endogenous and exogenous SPs for the secretion of recombinant GOX in Y. lipolytica. According to in silico results, the SP of GOX was predicted as suitable in terms of high secretory potential and of protein solubility and stability which is chosen for in vivo analysis. The recombinant Y. lipolytica strain produced 280 U/L of extracellular GOX after 7 days in YPD medium. The results show that the SP of GOX can be applied to efficient production of extracellular heterologous proteins and metabolic engineering in Y. lipolytica.
Subject(s)
Glucose Oxidase/biosynthesis , Glucose Oxidase/genetics , Protein Sorting Signals/physiology , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Yarrowia/genetics , Yarrowia/metabolism , Amino Acid Sequence , Aspergillus niger/genetics , Computer Simulation , Fungal Proteins/biosynthesis , Fungal Proteins/genetics , Fungal Proteins/metabolism , Glucose Oxidase/metabolism , Metabolic Engineering/methods , Recombinant Proteins/metabolism , Software , Yarrowia/growth & developmentABSTRACT
Trajectory tracking control for helicopters, which are widely used in severe situations such as military and rescue missions, is a challenging field of research. In helicopter system, the stability problem and predefined trajectories tracking are main challenges, especially in the presence of external disturbances and dynamic model uncertainties. Hence, a robust control design is needed for tracking the desired references. There has been a lot of motivation for solving these problems with simpler methods and also reducing the couplings in the helicopter system to achieve better performance, as the presented paper attempts to fill these gaps. This paper focuses on designing control laws for two-degree of freedom helicopter system while assuring the closed-loop stability. A nonlinear disturbance observer-based control (NDOBC) is designed for attenuating the effects of exogenous disturbances. Trajectory tracking controller and nonlinear disturbance observer are formulated in the form of two linear matrix inequality (LMI) problems. The closed-loop system stability, including controller and observer, is investigated by Lyapunov theorem. The effectiveness of the proposed design for tracking the trajectories (vertical flight and pitch angle rotor blade) and disturbance estimation is verified by simulation results.