Product Concentration Research Articles

The growth factor content as an indicator of platelet counts in platelet-rich plasma

BackgroundPlatelet contains growth factors that enhance tissue repair mechanisms, including epidermal growth factor (EGF), platelet-derived growth factor (PDGF-AA and −AB), and transforming growth factor (TGF)-β. Autologous platelet-rich plasma (PRP) has been shown to significantly improve the treatment of tendon injuries compared with hyaluronic acid and placebo. The topic of agreement between platelet concentrations and growth factors has been covered in some previous studies, but growth factor levels did not correlate well with platelet concentrations. MethodIn this study, autologous PRP was prepared by concentrating platelets through a J6-MI centrifuge. The automatic hematology analyzer Sysmex XN-20 was used to analyze the platelet concentration in PRP, and the PRP growth factors were determined by ELISA, including PDGF, transforming growth factor- β1 (TGF-β1), and EGF. Statistical analysis was conducted on data from 107 patients who received autologous PRP using Pearson correlation analysis. ResultsPearson correlation analysis revealed PDGF, TGF, and EGF had a strong positive correlation with the platelet concentration of the final PRP product (r = 0.697, p < 0.0001; r = 0.488, p < 0.0001; r = 0.572, p < 0.0001, respectively) ConclusionsThere was a strong positive correlation between the concentration of platelets in the final PRP product and the levels of PDGF-AB, TGF-β, and EGF. These results suggested straightforward and cost-effective growth factor tests can provide valuable information about platelet content in PRP.

Understanding How Porous Transport Layer Features Affect Proton Exchange Membrane Electrolyzer Performance

PEM Water electrolysis has emerged as a promising technology for the production of green hydrogen. A key component of PEM electrolyzer is the porous transport layer (PTL). The porous transport layer has numerous important roles in water electrolysis. In addition to enabling electrical conduction and water and gas transport, the PTL is necessary for maintaining excellent contact with the cell components. Cell performance is anticipated to be affected by PTL properties such as structure, composition, and thickness.This study delves into the critical contribution of porous transport layer properties to mass transport resistance, activation losses, catalyst layer resistance, and ohmic losses. I will present our experimental framework to deconvolute the impact of PTL properties such as thickness, porosity, and microporous layer on various overpotentials. Voltage loss breakdown analysis was conducted to determine kinetic, ohmic, mass transport, and catalyst layer losses. Theoretical calculations of thermodynamic voltage typically rely on standard reaction potentials adjusted for reactant and product concentrations, operating temperature, and pressure via Nernst corrections. Ohmic voltage, which accounts for contact resistances, bulk resistances, and ohmic losses from the membrane, was determined using high-frequency impedance spectroscopy measurements. To calculate losses from OER kinetics, a Tafel fit is subsequently implemented on the HFR-free voltage. Typically, this process tends to result in residual voltage at elevated current densities, including losses arising from mass transport of water and oxygen, resistance within the catalyst layer, and impacts stemming from ionic impurities. Ionic contamination is omitted from our analysis as a result of the short duration of the experiment.Our detailed analysis reveals that the properties of PTL can have a substantial impact on the performance of the water electrolyzer, which is crucial for enhancing the performance and durability of PEMWE. This study presents a novel framework for forecasting the performance of diverse PTL materials, which may be effectively used to drive the development and optimization of PTL for water electrolyzers. Figure 1

Scaling Considerations for the Commercialization of the Electrochemical CO2 Reduction Reaction

The Electrochemical CO2 Reduction Reaction (ECO2RR) is an attractive method to produce CO2-based chemicals. Formate is an ideal target compound due to its high atom efficiency, low electrical demand, and potential as a building block for carbon-negative products. In recent years, low temperature ECO2RR electrocatalyst research has developed rapidly, reporting impressive efficiencies (>90 % FE) at industrial relevant current densities (>200 mA/cm2). While these are essential metrics, there is less focus on the commercialization of these systems, such as electrode stability and process scalability. For industrial feasibility, ECO2RR electrolyzers must be >1 meter high, stable for 5 years, and operate under elevated temperatures and fluctuating pressures. This presents challenges to typical gas diffusion electrodes used in ECO2RR, which rely on a fine pressure gradients for efficient gas transport to the catalyst layer. Furthermore, high product concentrations and high CO2 utilization are essential for achieving an overall, energy efficient process. At Avantium’s Volta group, we industrialize ECO2RR processes. This presentation will demonstrate the scaling potential of these processes with examples from our pre-pilot units. Overall, we believe that ECO2RR will be a key technology to de-fossilize the chemical industry and valorize CO2 as the feedstock of the future. Figure 1

Adaptive model predictive control scheme for partially internal thermally coupled air separation column

Partially Internal Thermally Coupled Air Separation Column (P-ITCASC) is a highly energy-efficient and cost-effective technology. However, its complex dynamics resulting from thermal coupling pose a challenge to the operating stability of this technology. This article, therefore, proposes an adaptive model predictive control (AMPC) scheme for the P-ITCASC process. The controller incorporates an auto-regressive and exogenous inputs (ARX) model, a linear time-varying Kalman filter, and a recursive polynomial model estimator (RPME) algorithm. Within RPME, ARX polynomial models are identified and utilized to estimate the time-varying parameters and update the prediction model of the process. The process states are observed through the Kalman filter, and the constrained receding horizon optimization problem is solved using quadratic programming. This control scheme ensures the closed-loop system's feasibility and stability in the presence of output/input constraints. An adaptive generic model control, model predictive control, and adaptive internal model control schemes were also designed for benchmarking study. Numerical simulations show that AMPC is more efficient in handling nonlinear dynamics and maintaining product concentration to desired set points compared to other control schemes.

Latvian municipal budget expenditures on transport infrastructure and production in the context of improving the local economy

The article aims to study Latvian municipal budget expenditures on transport infrastructure and production in the context of improving the local economy. The authors hypothesize that the comparative priority of municipal budget expenditures on two items is determined by the state of the local economy; in municipalities with a more developed economy it is ‘transport’ rather than ‘production’ budget expenses that are more likely to improve the local economy, and in municipalities with a less developed economy – vice versa. The authors tested the hypothesis based on data for 2021 and 2022 (the time after the reform of the territorial-administrative structure of Latvia) for 43 Latvian municipalities using various methods of statistical analysis. The results show that the comparative priorities in Latvian municipal budget expenditures are determined not by the state of the local economy, but rather by the geographical (or geopolitical/geoeconomical) location of the municipality. As a result of this, Latvian municipalities are grouped into territorial clusters, using the agglomeration effect from the concentration of transport infrastructure or production. Over the past year, there has been a tendency towards ‘transport-production’ economic restructuring of the territory of Latvia, the reasons for which may be geopolitical situation in the Eastern Europe.

The effect of farm size and farmland use on agricultural diversification: a spatial analysis of Brazilian municipalities

Brazilian agriculture is characterized by the prevalence of small farms and regions with a high degree of rurality and dominance of the agricultural sector in the economy. These two characteristics affect the diversity of agricultural production in the country. Specifically, the article aims to analyze the effects of size farm and farmland use on agricultural diversification and the effects of demand and technology adopted by farmers. The database encompasses 4298 Brazilian municipalities from 1996 to 2017 (the last three agricultural censuses). Empirically, we consider spillover effects by estimating spatial models at the municipal level using panel data, highlighting the importance of location and neighborhood. The study’s findings indicate a tendency toward local concentration of agricultural production in the country, despite the balance between municipalities with diversified and concentrated production. The results showed a significant effect of small farms and the municipalities’ rurality degree on the agricultural output diversification. The study provides insights into the discussion on measures to strengthen support for small properties and regions that diversify crops to ensure economic efficiency and food security.

A multi-ion transport model of Cu-Zn-Fe trimetallic couple in near-neutral NaCl solution

A numerical model was proposed to investigate the corrosion behavior of Cu-Zn-Fe couple in near-neutral 3.5 wt% NaCl. Evolution of current density, pH and soluble corrosion products were simulated in one-dimensional scale. The model predicted acidification on Zn surface and alkalization on Cu and Fe surfaces. pH evolution is related to corrosion products distribution. Zn2+ is the dominant specie formed on the middle of Zn surface. Zn hydrolytes are preferentially formed above the resin. Above the cathode surfaces distant from Zn, the concentration of corrosion products remains as zero.

Microbiota in Mild Inflammatory Bowel Disease (IBD) Can Be Modulated by Beta-Glucans and Mannanoligosaccharides: A Randomized, Double-Blinded Study in Dogs.

Inflammatory bowel disease (IBD) in dogs is the most common chronic gastrointestinal disease in dogs. Its etiology evolves an aberrant immunological response towards food antigens and indigenous bacteria in the gut bacteria and, consequently, dysbiosis. Prebiotics provide substrates for the growth of beneficial bacteria and promote the production of beneficial fermentation products. This study aimed to evaluate the effects of oral supplementations of beta-glucans and mannanoligosaccharides (MOSs) over 60 days in fecal microbiota and fecal concentrations of fermentation products in dogs with mild IBD. Eighteen dogs with mild IBD were divided into three experimental groups in a blinded and randomized manner: A-dogs received 0.1% of a beta-glucan-based prebiotic, B-dogs received 0.1% of a MOS + beta-glucan-based prebiotic, and C-dogs received 0.1% of a placebo. Fecal microbiota was analyzed using the latest generation 16S rRNA sequencing (Illumina®). Relative abundances of each taxon were analyzed using a generalized linear model, and fermentation products using a mixed model. A significance level of p was used. The prebiotics positively modulated the bacterial population of Firmicutes and Bacteroidetes. Treatment A improved alpha diversity and populations of beneficial bacteria. Beta-glucan supplementation for 60 days had beneficial effects on modulating intestinal microbiota in dogs with mild IBD.

Carbon-Monoxide Laser Absorption Spectroscopy Measurements over Ablating Graphite in a Shock Tunnel

Measurements of carbon monoxide (CO) during air–carbon ablation of graphite are performed in the Sandia Hypersonic Shock Tunnel. Resistive heating is used to bring graphite samples to wall temperatures (Tw=1250–1630 K) as measured by an imaging pyrometer. The heated models are subjected to a flow condition of H0=10.6 MJ/kg, Tr(∞)=630 K, P∞=300 Pa, and u∞=4240 m/s. Tunable diode laser absorption spectroscopy measures CO temperature and concentration within the boundary layer at 50 kHz. Ablation product concentrations from experiments are presented as a function of time, including the transient startup of the tunnel. The measured CO concentration increases by approximately a factor of 2 as surface temperatures increase from 1250 to 1630 K. Finally, the CO concentration is observed to be lower than that predicted by several air–carbon ablation models, with the best agreement occurring at the higher surface temperature.

Inhibiting salt precipitation on the gas diffusion electrode surface in gas-phase CO2 electroreduction to formate by using an acidic anolyte

The gas-phase CO2 electroreduction to formate represents one of the most promising CO2 conversion processes due to its scalability, as the product concentration surpasses 30 % wt. However, the use of alkaline media anolytes, intended to improve the efficiency and selectivity of formate production, causes the carbonate and bicarbonate salts to precipitate over the Gas Diffusion Electrode (GDE). This precipitation clogs the porous structure, leading to a rapid loss of electrode stability. In this work, we address this issue by proposing the use of acid anolytes, based on K2SO4, to mitigate the precipitation of insoluble salt on the GDE structure, thereby achieving longer and more stable GDE operation times. Various anolyte concentrations and pHs are evaluated, with 0.3 M K2SO4 at pH 1, adjusted using H2SO4, providing the best compromise. This condition inhibited potassium carbonate and bicarbonate precipitation, as observed through XRD, SEM, and EDS analysis, while maintaining high CO2 electroreduction to formate performance, with a concentration of 69 g L−1, and a Faradaic Efficiency of 33 %. Furthermore, the anolyte flowrate per geometric area is optimized to maximize the system performance. At a flowrate of 0.85 mL min−1 cm−2, enhanced concentration of 88 g L−1 and a Faradaic Efficiency of 42 % are reached. Besides, long-term experiments demonstrated that GDEs used with alkaline conditions exhibit a larger deactivation constant (0.7652) compared to the GDEs used with acid anolytes (0.3891). This indicates that salt precipitation more rapidly reduces GDE performance under alkaline conditions. These results represent a promising advance in obtaining longer-lasting GDEs, which are crucial to successfully scaling up the CO2 electroreduction to formate.

The Influence of Pomace Powder of Musky Squash on the Characteristics of Foamy Confectionery Products during Storage

This paper analyzes the possibility of using pomace powder of musky squash (PPMS, 10–30% of the formulation) for the manufacture of foamy confectionery products based on Jerusalem artichoke syrup, which is a natural substitute for sugar syrup used in the food industry. The content of biologically active compounds (polyphenols, carotenoids) as well as the antimicrobial and antioxidant properties of pumpkin powder were evaluated. Sensory analysis was applied to measure the degree of product acceptance and the analysis revealed that the optimal amount of PPMS accepted by the tasters was 15%. The addition of PPMS increased pH and free water retention, color, and lightness intensification. During the storage period (40 days), the hardness and gumminess showed an essential increase and the cohesion of the samples gradually decreased. The addition of PPMS led to the improvement of textural parameters, thus contributing to the extension of the shelf life of products by 10 days, compared to the control sample. Mutual information analysis was applied to determine the influence of PPMS concentration and storage time of foamy confectionery products on mean total score, mean sensory profile score, moisture content, water activity, antioxidant activity, hardness, cohesiveness, and gumminess. The results of this research indicate that the use of pumpkin pulp in the manufacture of foamy confectionery products can significantly increase their biological value and sensory characteristics and ensure an extension of the products’ shelf life.

Computer‐Aided Protein Surface Modification Strategy to Improve the Thermostability of α‐Amylase

AbstractStability under high‐temperature environments is crucial for amylase to function in starch‐based industries. This study develops a method of modifying protein surfaces by combining computer‐aided tools including FoldX, PoPMuSiC, Discovery Studio, and I‐Mutant 2.0 with conserved sequence analysis. A truncated α‐amylase ∆AmyPTG from Parageobacillus thermoglucosidasius DSMZ 2542 is rationally designed through this method to improve its thermostability. Seven single‐site variants are constructed and five of them displayed enhanced thermostability. Next, three double‐site variants are constructed with one particularly successful double‐site variant N31RT213R, exhibiting a 4.3‐fold longer half‐life at 80 °C. Notably, the specific activity of N31RT213R reaches 10 567.16 U mg−1, higher than ∆AmyPTG (6645.43 U mg−1). When applied to the corn starch liquefaction reaction, the mutant N31RT213R gets a higher yield of product concentration of about 255.70 µg mL−1, compared to 190.72 µg mL−1 for ∆AmyPTG. Intramolecular forces analysis and surface electrostatic charges analysis are conducted to determine possible causes for the improvement. Also, molecular dynamics simulation is used to analyze the flexibility shifts of the entire protein. This innovative rational engineering approach has proven to be a successful strategy for the selection of hot spots for protein thermostability evolution and has the potential to be applied to other enzymes.

Effect of surfactants on enzymatic hydrolysis of PET

Enzyme is difficult to adsorb on the surface of high-crystallinity poly(ethylene terephthalate) fibers (PET，crystallinity of 48.56 %) due to the high hydrophobicity of PET fibers. Surfactants can effectively reduce the PET/water interface tension and improve the adsorption of enzyme on PET fibers, increasing the degradation of PET fibers promoted by enzyme. In this paper, different nonionic surfactants (Triton X-100, Triton X-114, Triton X-405, PEG 200, PEG 400, PEG 600, Tween 20, Tween 80) were selected to investigate the effect of surfactant on the degradation of PET fibers by enzyme. It was found that the addition of Triton X-405 can improve the concentration of degradation products. However, other surfactants selected in this paper, such as Tween-80 caused the decrease of the degradation yields. The results indicated that the structure of surfactant plays a very important roll on the degradation of PET catalyzed by enzyme. This is probably due to the transformation of enzyme conformation induced by surfactant, and affects on the activity of enzyme. The hydrophilic surface is beneficial to the adsorption of enzyme onto the surface of PET fibers, and further improve the degradation of PET fibers.

Cryogenic-membrane separation process for helium extraction and ethane co-production from natural gas

In order to address the defects of high energy consumption and low efficiency in the single cryogenic separation process for helium extraction, this paper integrate post-expansion nitrogen cycle refrigeration with membrane separation to establish a novel natural gas cryogenic-membrane helium recovery process. Based on four mainstream processes for ethane recovery from natural gas, an optimal ethane recovery method is selected and incorporated into the proposed cryogenic-membrane helium recovery process. The process is then simulated using ASPEN HYSYS software. The effects of operating parameters on critical equipment energy consumption, helium product concentration and ethane recovery were evaluated. The simulation results indicate that in the proposed helium recovery process, the concentration of refined helium reaches 99.6 %, and the ethane recovery rate is 90.13 %. Compared to the single helium extraction process, the total compressor energy consumption in our process is reduced by 23.10 %, and the integrated energy consumption is reduced by 20.4 %.

Recycling potato waste for the production of blue pigments by Streptomyces lydicus PM7 through submerged fermentation

BackgroundDiscarded potato is the most abundant potato waste and represents a worldwide disposal problem to the potato industry. This agricultural waste contains valuable nutrients that could be used as substrate to obtain diverse high value-added microbial products, such as biopigments. The aim of this work was to evaluate the use of discarded potato as a sole substrate source for producing blue pigments by Streptomyces lydicus PM7 through submerged fermentation.ResultsInitially, the traditional culture medium ISP2 was established as suitable for inoculum preparation, as it allowed high growth rates and consumption of ~ 75% reducing sugar, leading to 1.3 g L−1 dry biomass at 72 h of incubation. The formulated discarded potato broth (DPB) medium was evaluated together with five other traditional liquid culture media (potato dextrose broth, ISP2, ISP3, ISP4, and ISP5) for producing blue pigments by S. lydicus PM7. The highest blue pigment production was obtained by using DPB medium, reaching ~ 0.97 g L−1, followed by ISP5 (~ 0.36 g L−1). In terms of evaluating the concentration of discarded potato powder, the highest concentration of blue pigments was obtained with 16 g L−1, compared to concentrations of 4, 8, and 32 g L−1. In general, a notable increase in total proteins (~ 14 g L−1 in biomass; ~ 8 g L−1 in medium) and reducing sugars (~ 5 g L−1) on the fifth day of DPB fermentation was observed, at which time the production of blue pigments began. These data proved that S. lydicus PM7 is able to degrade potato wastes during submerged fermentation and to direct metabolism towards the formation of biopigments. Chromatographic analysis revealed that the main blue pigment produced by new strain in this complex medium is actinorhodin.ConclusionsDiscarded potato favored the production of blue pigments by S. lydicus PM7 under submerged fermentation, leading to final product concentration almost three times higher than others traditional Streptomyces culture media. To the best of our knowledge, this is the first report on the production of actinorhodin by the specie S. lydicus, as well as on this pigment synthesis based on an agricultural waste as a sole nutrient source for fermentation process. The findings showed that potato waste could be a potential byproduct for replacement of commercial culture media using for this same purpose.Graphical

Enhancement of culled ewes’ meat quality: Effects of aging method and time

This study assesses the impact of wet and dry aging, over 35 days, on various physico-chemical, colorimetric, oxidative, volatolomic, and sensory attributes of meat from culled ewes. Water holding capacity of dry-aged (DA) meat increased from day 28 and was significantly higher than wet-aged (WA) meat. Cooking loss of DA meat decreased, and it was lower than that of WA meat. Warner Bratzler shear force increased in DA meat but decreased in WA meat during aging. Higher oxidation product concentration in DA meat likely results from oxygen exposure. Some aldehydes and ketones peaked at day 7 in DA meat, surpassing levels in WA meat. Overall liking scores favored DA meat at day 14 and 21 but declined from day 14 to 35, coinciding with increased pentanal content. Dry aging could improve the acceptability of culled ewes' meat more than wet aging, but in short aging time (14 days).

Response of photosynthetic characteristics and yield of grape to different CO2 concentrations in a greenhouse.

Due to the enclosed environment of greenhouse grape production, the supply of CO2 required for photosynthesis is often insufficient, leading to photosynthetic downregulation and reduced yield. Currently, the optimal CO2 concentration for grape production in greenhouses is unknown, and the precise control of actual CO2 levels remains a challenge. This study aims to investigate the effects of different CO2 concentrations on the photosynthetic characteristics and yield of grapes, to validate the feasibility of a CO2 gas irrigation system, and to identify the optimal CO2 concentration for greenhouse grape production. In this study, a CO2 gas irrigation system combining CO2 enrichment and gas irrigation techniques was used with a 5-year-old Eurasian grape variety (Vitis vinifera L.) 'Flame Seedless.' Four CO2 concentration treatments were applied: 500 ppm (500 ± 30 µmol·mol-1), 700 ppm (700 ± 30 µmol·mol-1), 850 ppm (850 ± 30 µmol·mol-1), and 1,000 ppm (1,000 ± 30 µmol·mol-1). As CO2 concentration increased, chlorophyll a, chlorophyll b, and carotenoids in grape leaves all reached maximum values at 700 ppm and 850 ppm during the same irrigation cycle, while the chlorophyll a/b ratio was lower than at other concentrations. The net photosynthetic rate (Pn) and water use efficiency (WUE) of grape leaves were the highest at 700 ppm. The transpiration rate and stomatal conductance at 700 ppm and 850 ppm were significantly lower than those at other concentrations. The light saturation point and apparent quantum efficiency reached their maximum at 850 ppm, followed by 700 ppm. Additionally, the maximum net photosynthetic rate, carboxylation efficiency, electron transport rate, and activities of SOD, CAT, POD, PPO, and RuBisCO at 700 ppm were significantly higher than at other concentrations, with the highest yield recorded at 14.54 t·hm-2. However, when the CO2 concentration reached 1,000 ppm, both photosynthesis and yield declined to varying degrees. Under the experimental conditions, the optimal CO2 concentration for greenhouse grape production was 700 ppm, with excessive CO2 levels gradually inhibiting photosynthesis and yield. The results provide a theoretical basis for the future application of CO2 fertilization and gas irrigation techniques in controlled greenhouse grape production.

Effect of biocatalysts β-galactosidase loading in their performance in the kinetically controlled synthesis of lactulose

β-galactosidase from Kluyveromyces lactis has been immobilized on chitosan-glutaraldehyde particles employing different enzyme loadings (in a range of 0.7–7 mg/g of support). The biocatalysts had been later utilized to produce lactulose by transglycosylation using milk whey supplemented with fructose. The amount of produced lactulose decreased when the enzyme loading increased, from around 18 mg/mL using the biocatalysts with only 0.7 mg/g to around 7 mg/mL using the biocatalyst with a loading of 7 mg/mL. The results showed in this paper shows the great effect of the substrates and product concentration gradients inside the biocatalyst particle, not only lactulose, but also glucose and galactose. That is, the use of a excessive enzyme loading can lead to a significant worsening of the β-galactosidase biocatalyst performance in kinetically controlled synthesis.

Effect of pullulan active packaging, incorporated with silver nanoparticles, on cholesterol oxidation product concentrations in boiler meat during storage

Effect of pullulan active packaging, incorporated with silver nanoparticles, on cholesterol oxidation product concentrations in boiler meat during storage

Effect of rabbit urine foliar spray on the yield and post-harvest quality of tomato (Solanum lycopersicum L.)

Of all vegetable crops, tomato occupies the second-largest cultivated land after potato. However, its production is often lamed by insufficient nutrient supply and invasion by insect pests. Unlike inorganic fertilizers and synthetic pesticides commonly used, rabbit urine supplies nutrients to the crops, controls insect pests and has low mammalian toxicity. However, the most suitable rabbit urine foliar spray concentration for tomato production is currently unknown. The experiment was conducted in a randomized complete block design with six treatments and four blocks to evaluate the effect of different concentrations of rabbit urine foliar spray on the yield and post-harvest quality of tomato. The six treatments used include: five concentrations of rabbit urine (100%, 40%, 25%, 18.2% and 0%) and 0.1% Duduthrin 1.75EC. Results indicated that treatment 18.2% rabbit urine registered the highest marketable yield (129.14 t/ha) in trial 1. In trial 2, treatment 25% rabbit urine recorded the highest marketable yield (165.08 t/ha). These two treatments gave the highest marketable yields due to their sufficient nutrient supply, optimal pest control and zero foliage scorching. Unlike fruit firmness and sugar acid ratio, total soluble solids and titratable acidity increased with increase in rabbit urine concentration. Therefore, a rabbit urine foliar spray concentration of 25% optimally improves yield and post-harvest quality of tomato. More research work can be done to determine the effect of spraying intervals of rabbit urine on the yield and post-harvest quality of tomato.