O2 CO2 Research Articles

Roadmap for Sustainable Mixed Ionic‐Electronic Conducting Membranes

AbstractMixed ionic‐electronic conducting (MIEC) membranes have gained growing interest recently for various promising environmental and energy applications, such as H2and O2production, CO2reduction, O2and H2separation, CO2separation, membrane reactors for production of chemicals, cathode development for solid oxide fuel cells, solar‐driven evaporation and energy‐saving regeneration as well as electrolyzer cells for power‐to‐X technologies. The purpose of this roadmap, written by international specialists in their fields, is to present a snapshot of the state‐of‐the‐art, and provide opinions on the future challenges and opportunities in this complex multidisciplinary research field. As the fundamentals of using MIEC membranes for various applications become increasingly challenging tasks, particularly in view of the growing interdisciplinary nature of this field, a better understanding of the underlying physical and chemical processes is also crucial to enable the career advancement of the next generation of researchers. As an integrated and combined article, it is hoped that this roadmap, covering all these aspects, will be informative to support further progress in academics as well as in the industry‐oriented research toward commercialization of MIEC membranes for different applications.

Impact of cervical spinal cord injury on the relationship between the metabolism and ventilation in rats.

Cervical spinal cord injury typically results in respiratory impairments. Clinical and animal studies have demonstrated that respiratory function can spontaneously and partially recover over time after injury. However, it remains unclear whether respiratory recovery is associated with alterations in metabolism. The present study was designed to comprehensively examine ventilation and metabolism in a rat model of spinal cord injury. Adult male rats received sham (i.e., laminectomy) or unilateral mid-cervical contusion injury (height of impact rod: 6.25 or 12.5 mm). Breathing patterns and whole body metabolism (O2 consumption and CO2 production) were measured using a whole body plethysmography system conjugated with flow controllers and gas analyzer at the acute (1 day postinjury), subchronic (2 wk postinjury), and chronic (8 wk postinjury) injury stages. The results demonstrated that mid-cervical contusion caused a significant reduction in the tidal volume. Although the tidal volume of contused animals can gradually recover, it remains lower than that of uninjured animals at the chronic injury stage. Although O2 consumption and CO2 production were similar between uninjured and contused animals at the acute injury stage, these two metabolic parameters were significantly reduced in contused animals at the subchronic to chronic injury stages. Additionally, the relationships between ventilation, metabolism, and body temperature were altered by cervical spinal cord injury. These results suggest that cervical spinal cord injury causes a complicated reconfiguration of ventilation and metabolism that may enable injured animals to maintain a suitable homeostasis for adapting to the pathophysiological consequences of injury.NEW & NOTEWORTHY Ventilation and metabolism are tightly coupled to maintain appropriate energy expenditure under physiological conditions. Our findings demonstrate that cervical spinal cord injury results in the differential reduction of ventilation and metabolism at the various injury stages and leads to alterations in the relationship between ventilation and metabolism. These results from an animal model provide fundamental knowledge for understanding how cervical spinal cord injury impacts energy homeostasis.

PSIX-10 Effect of different levels of DMI on O2 consumed, CO2 released, growth and carcass characteristic in feedlot cattle

Abstract Our objective was to determine the effect of different levels of dry matter intake (DMI) on O2 consumption, CO2 emission, growth, and carcass characteristic in feedlot cattle. The experiment used 60 individually fed backgrounded Angus × SimAngus-crossbred steers (n = 30) in a randomized complete block design. Steers (paired blocked by body weight and gain to feed ratio (G:F) were randomly allocated to one of the following treatments: ad-libitum (AI) or restricted intake (RI; the same diet fed at 85% of the AI) finishing diet. The diet contained 61% cracked corn, 9% corn silage, 15% DDGS, 5% soyhulls, and 10% of a protein-mineral-vitamin premix. Measurement of CO2 emission, and consumption of O2, were taken using the Greenfeed system (n = 15/treatment) once the steers were fed for 140 days. Plasma and gas samples were collected 10 d before slaughter, 1 h before and 2 h after feeding. Plasma glucose and insulin concentration and gasses (O2 and CO2) were analyzed using the MIXED procedure of SAS evaluating the fixed effect of treatment, time (repeated measurement) and their interaction. Growth and carcass characteristics were analyzed with a similar model, without the time statement and its interaction. Compared with RI, AI steers had greater (P < 0.01) DMI and average daily gain (ADG). Steers on AI tended to have greater final body-weight (BW) (P = 0.07) and ribeye area (P = 0.09) (Table 1). There was no effect of treatment (P ≥ 0.11) on G:F, subcutaneous (BF) and intramuscular (IM) fat, O2 consumption and CO2 emission. Plasma glucose concentration of AI steers were greater before and after feeding than RI (P < 0.05; Table 2). In conclusion, feeding steers ad-libitum increased DMI, ADG, and plasma glucose concentration, but does not affect G:F, BF, IM fat, CO2 emission, and consumption of O2.

Membrane Oxygenator for Extracorporeal Blood Oxygenation

Extracorporeal blood oxygenation has become an alternative to supply O2 and remove CO2 from the bloodstream, especially when mechanical ventilation provides insufficient oxygenation. The use of a membrane oxygenator offers the advantage of lower airway pressure than a mechanical ventilator to deliver oxygen to the patient’s blood. However, research and development are still needed to find appropriate membrane materials, module configuration, and to optimize hydrodynamic conditions for achieving high efficient gas transfer and excellent biocompatibility of the membrane oxygenator. This review aims to provide a comprehensive description of the basic principle of the membrane oxygenator and its development. It also discusses the role and challenges in the use of membrane oxygenators for extracorporeal oxygenation on respiratory and cardiac failure patients.

Neuromodulatory Support for Breathing and Cardiovascular Action During Development.

Neonatal survival requires precise control of breathing and cardiovascular action, with fatal consequences or severe injury without support. Prematurity presents multiple opportunities to disrupt cardiorespiratory regulation, leading to expressions of apnea of prematurity, periodic breathing, and inappropriate cardiovascular responses to apnea. Failed breathing control can result from altered breathing drives, typically arising from untimely development of sensory or motor coordination processes. Some drives, such as temperature, are a special concern in neonates with low body mass, enhancing susceptibility to rapid body cooling. Chemical drives, such as pH or CO2 or O2, may be inadequately developed; in some conditions, such as congenital central hypoventilation syndrome (CCHS), breathing responses to CO2 or low O2 may be reduced or absent, and coupling of cardiovascular responses to breathing changes are abolished. Sleep states exert profound influences on both chemical and temperature drives, with rapid eye movement (REM) sleep potentially modifying descending temperature influences, and state transitions significantly altering respiratory responses to chemical stimuli. In addition, neonates spend the majority of time in REM sleep, a state which induces a generalized inhibition of skeletal muscle activity that abolishes muscle tone to upper airway and thoracic wall muscles, enhancing the likelihood for obstructive sleep apnea. Although disrupted regulatory drives can often be replaced by positive (or negative) pressure ventilation, such as continuous positive airway pressure or enhanced by manipulating neurotransmitter action via caffeine, those approaches may exert negative consequences in the long term; the lungs of neonates, especially premature infants, are fragile, and easily injured by positive pressure. The consequences of caffeine use, acting directly on neural receptors, although seemingly innocuous in the near-term, may have long-term concerns and disrupts the integrity of sleep. The developmental breathing field needs improved means to support ventilation when one or more drives to respiration fail, and when the cardiovascular system, depending heavily on interactions with breathing, is compromised. Neuromodulatory procedures which manipulate the vestibular system to stabilize breathing or use tactile or proprioceptive stimuli to activate long-established reflexive mechanisms coupling limb movement with respiratory efforts can provide support for central and obstructive apnea, as well as for periodic breathing and cardiovascular action, particularly during sleep.

Modelamiento matemático para el monitoreo y control de las condiciones de degradación aerobia de la fracción orgánica de los residuos sólidos urbanos

Compost has applications in agriculture and environmental restoration. Therefore, it is important to evaluate control parameters that help accelerate and improve the aerobic degradation and stabilization processes of organic waste. A mixture of pruning waste, organic fraction of municipal solid waste, paper, and sawdust was subjected to an aerobic degradation process using mature and stabilized compost from the Bordo Poniente composting plant in Mexico City at different aeration rates (0.064, 0.125, 0.201 and 0.392 L air min-1 kg-1 dry matter) in laboratory-scale bioreactors for 140 h. On-line monitoring of CO2 production and O2 consumption and their setting to mathematical models allowed to select the conditions to obtain a stable compost, as well as to analyze the concentration of trehalose, citric acid, glucose, xylose, erythritol, acetic acid, fructose, and the production of oxalic acid during the degradation process. Germination rates higher than 80% were obtained in the growth of Lactuca sativa seeds in organic waste extracts after aerobic degradation. A vkgm of 0.392 L air kg-1 min-1 DM is suggested as a strategy to obtain a compost free of phytotoxic compounds for the application of compost in agriculture or environmental restoration and a null maintenance coefficient.

Effect of Temperature and Time on Oxygen Consumption by Olive Fruit: Empirical Study and Simulation in a Non-Ventilated Container

Fermentation processes within olive fruit jeopardize the quality of the extracted oil. Aeration, temperature, and time play a crucial role in attaining the critical threshold at which an aerobic respiration shifts towards anaerobic. In this work, the O2 consumption and CO2 production of olive fruit kept in a closed container at different temperatures (5–45 °C) were measured over 7 h. The data allowed us to describe the relationship between the temperature and the respiration rate as an Arrhenius function and simulate the oxygen consumption in the inner part of a container full of fruit with low aeration, considering the generated respiration heat over time. The simulation revealed that olives risk shifting to anaerobic respiration after 3 h at 25 °C and less than 2 h at 35 °C when kept in a non-ventilated environment. The results underline the irreversible damage that high day temperatures can produce during the time before fruit processing, especially during transport. Lowering, as soon as possible, the field temperature thus comes to the fore as a necessary strategy to guarantee the quality of the olives before their processing, like most of the fruit that is harvested at excessive temperatures.

HUBUNGAN PARTUS LAMA DENGAN KEJADIAN ASFIKSIA PADA BAYI BARU LAHIR DI UPT PUSKESMAS WATAMPONE

Abstract. Newborn asphyxia can be associated with several conditions of pregnancy and birth. The baby is in a high-risk state and the mother is in a high-risk pregnancy. At the age of 30 weeks of gestation, the fetal lungs have shown maturation both anatomically and functionally, although the fetus does not carry out respiratory movements unless there is a disturbance that can cause hypoxia / anoxia. In the asphyxia state, the baby is deficient in O2 and excess CO2 which can lead to acidosis. This condition is the cause of failure to adapt and often progresses to respiratory distress syndrome and in the first days of birth.To know the relationship between old labor and the incidence of asphyxia in newborns at the UPT Puskesmas Watampone.The type of research used in this study was an analytic survey with a cross sectional study design. So that the number of samples that meet the criteria is determined as many as 20 people.The results showed that there was a relationship between prolonged labor and the incidence of asphyxia in newborns, with the chi square test value obtained p-value = 0.001 p <0.05. Of the 20 respondents, the highest was found in the category of non-labor for a long time and did not experience asphyxia as many as 13 respondents (65%). While the lowest was in the category of prolonged labor and not experiencing asphyxia as many as 2 respondents (10%). Conclusion: There is a relationship between prolonged labor and the incidence of asphyxia in newborns at the UPT Puskesmas Watampone

Carbon and Oxygen Gas Exchange in Woody Debris: The Process and Climate-Related Drivers

The carbon-to-oxygen relationship and gas exchange balance, organic carbon to CO2 conversion intensity and efficiency, and their relevance to climate parameters and wood decay fungi were investigated for birch woody debris (WD) in the Mid-Urals mixed pine and birch forests. It was shown that, within the range of temperatures from 10 to 40 °C and relative moisture (RM) of wood of 40% and 70%, aerobic gas exchange was observed in the WD, encompassing the physiologically entwined processes of CO2 emission and O2 uptake. Their volumetric ratio (0.9) confirmed that (1) the WD represents a globally significant CO2 source and appropriate O2 consumer and (2) the oxidative conversion of organic carbon is highly efficient in the WD, with an average ratio of CO2 released to O2 consumed equal to 90%. The balance of carbon-to-oxygen gas exchange and oxidizing conversion efficiency in the WD were not affected by either fungal species tested or by moisture or temperature. However, the intensity of gas exchange was unique for each wood decay fungi, and it could be treated as a climate-reliant parameter driven by temperature (Q10 = 2.0–2.1) and moisture (the latter induced a corresponding trend and value changes in CO2 emission and O2 uptake). Depending on the direction and degree of the change in temperature and moisture, their combined effect on the intensity of gas exchange led to its strengthening or weakening; otherwise, it was stabilized. Aerobic respiration of wood decay Basidiomycetes is an essential prerequisite and the major biotic factor in the WD gas exchange, while moisture and temperature are its climatic controllers only.

Preparation of high-precision CO2 with known triple oxygen isotope for oxygen isotope analysis

ABSTRACT The objective of this work is to propose a more effective way to prepare an in-house CO2 with known triple oxygen isotope compositions. The major experimental steps include: (1) the O2 is combusted to CO2 on a graphite rod at 750 °C with Pt-catalyst for 3–4 min; and (2) converted CO2 is subsequently purified by two cryogenic traps. The results show high reproducibility of δ 13C and δ 18O values of the converted CO2 within 0.010–0.020 ‰ and 0.006–0.010 ‰ (1σ, SD), and the identical δ 18O value within error with that of the original O2. Additionally, we have measured the triple oxygen isotope compositions of converted CO2 using an O2–CO2 Pt-catalyzed oxygen-isotope equilibration method. The measured δ 17O values of CO2 show high reproducibility within 0.006 ‰ (1σ, SD), and are identical within error with the original O2 as well. Notably, our experiments also found that the O2 with heavier oxygen isotope ratios (δ 18O > 40 ‰, VSMOW) might have a lesser conversion efficiency, and this effect, combined with the lighter isotope preferential fractionations during the reaction processes of O2 to CO and CO to CO2, may explain the observed lower 17O/16O and 18O/16O ratios of the converted CO2 relative to the original O2.

Mixed ionic-electronic conducting composite-based ceramic-carbonate dense membranes for CO2/O2 counter-permeation and CO oxidation

Dense inorganic membranes made of the ionic conductor Ce0.80Sm0.15Sr0.05O2-δ and the electronic-ionic conductor Sm0.6Sr0.4Al0.3Fe0.7O3-γ were infiltrated with molten carbonates. One side of the membrane is supplied with CO, and the opposite side is fed with O2. The CO oxidation and CO2/O2 counter-permeation fluxes are studied as functions of temperature and weight percent of the mixed ionic-electronic conductor phase. The O2 counter-permeation was correlated to the oxygen ionic flux counter-permeation consumed for CO oxidation and CO32− formation for CO2 permeation. The Ce0.80Sm0.15Sr0.05O2-δ/Sm0.6Sr0.4Al0.3Fe0.7O3-molten carbonates system exhibits higher oxygen ionic flux counter-permeation than Ce0.80Sm0.15Sr0.05O2-δ-molten carbonates system, producing a larger amount of CO conversion in the first case. The limiting factor for the O2 counter-permeation and CO2 permeation in triple-phase membranes is the oxygen ionic conductivity. In dual-phase membranes, the redox reaction for oxygen dissociation becomes vital for oxygen ionic flux. However, the limiting factor for the O2 permeation flux is the oxygen ionic transport in the ceramic phase. On other hand, the limiting factor for the CO2 permeation is attributed to both the ionic transport in the molten carbonates and the ceramic phase. The weight percent of the perovskite Sm0.6Sr0.4Al0.3Fe0.7O3 was varied to study the effect of its electronic property on the CO2/O2 counter-permeation flux and CO oxidation, establishing that the electronic nature of Sm0.6Sr0.4Al0.3Fe0.7O3 enhances the formation of oxygen ions. This increases the carbonate ions concentration on the surface of the CO-supply membrane side, which raises the driving force for CO2 permeation. Also, the CO2 formation rate on the oxygen supply side is faster than on the CO-supply membrane side. The formation rate of molecular oxygen is lower than the CO2 formation rate.

B-PO05-020 REMODELING IMPROVES EXERCISE CAPACITY IN DOGS WITH AV BLOCK

Children with congenital complete atrioventricular block (AVB) do not often report exercise intolerance due to compensatory mechanisms. The effect of cardiac remodeling being absent and present after AV block on exercise capacity has not yet been reported. We studied the cardiorespiratory changes due to exercise at three different timepoints after inducing AV block in dogs. Mongrel dogs (n=8) were placed on a treadmill with a 10% incline in a custom-build closed chamber and performed a moderate exercise protocol (10 minutes at a speed of 6 km/h). Dogs ran at sinus rhythm (SR), at two days after AV block (AVB2d) lacking cardiac remodeling, and at three and six weeks of chronic AV block (CAVB) remodeling (CAVB3 and CAVB6, respectively). ECG tracings were recorded via electrodes on the back. Stroke volume and cardiac output were recorded via a thoracic electrical bioimpedance-based device (PhysioFlow®). pO2, pCO2, SpO2 and pH levels were determined from venous blood samples. O2 consumption (VO2) and CO2 production (VCO2) were measured within the chamber. All dogs completed the exercise protocol at SR, CAVB3 and CAVB6, but 5/8 dogs failed at AVB2d (average run duration: 7min23sec, SD: 2min38sec), due to ventricular tachycardia and/or staggering. Changes in heart rate, stroke volume and cardiac output upon exercise were not different between the timepoints after AV block. At AVB2d, pO2 was lower (3.3±1.1 vs. 5.2±0.7 kPa (SR), p<0.01), the SpO2 was decreased (31±16 vs. 67±7 % (SR), p<0.001), the pCO2 was higher (7.3±1.4 vs. 5.5±0.3 kPa (SR), p<0.01), and the pH was decreased (7.23±0.06 vs. 7.36±0.02 (SR), p<0.001) at 2min exercise. Similar values were found at 5min exercise e.g., for pCO2 (6.8±1.8 vs. 5.1±1.3 kPa (SR), p<0.05) and pH (7.22±0.08 vs. 7.37±0.03 (SR), p<0.001). Venous blood parameters were not different between SR, CAVB3 and CAVB6 at rest and during exercise. At the end of the run (at steady state), VO2 and VCO2 are lowest at AVB2d with a 10% and 5% decrease, respectively, compared to SR (p=0.05 and 0.33). Dogs without remodeling after AV block have a reduced exercise capacity, which seems to be reflected in changes in cardiorespiratory parameters. Remodeling after chronic AV block improves the exercise capacity in dogs.

A zero carbon emission CCGT power plant and an existing steam power station modernization scheme

CO2 emission reduction is one of the major challenges of the future. It is impossible to reject fossil fuels altogether, since renewable energy sources are insufficient to satisfy growing energy demands. Therefore, the creation of a fossil fuel power plant with zero carbon emission becomes an important task.In this work, а combined cycle gas turbine (CCGT) power plant with natural gas oxy-fuel combustion and pressurized heat recovery steam generator is presented. Flue gas water vapor condensation provides low-grade heat utilization and more than 97 % CO2 mass concentration in exhaust gases. The high purity of the captured CO2 simplifies further CO2 use. The evaluated efficiency is 51.6 % without considering the O2 production and CO2 compression costs and 43.5 % if they are included. This plant can compete with the existing CCGT power plants considering the carbon pricing and CO2 capture and storage.The existing power station modernization scheme is proposed in this study. The plant efficiency increases by 8–11 % after modernization. The unification and localization possibility, low capital costs and mass production allow for this scheme in developing countries. The study is based on common Russian power plants and turbines.

Corrosion behavior of 35CrMo steel in a CO2/O2 coexistent simulating environment of fire-drive tail gas

Fire-driven technology has triggered significant interest as an effective technology to improve oil recovery. However, corrosion can easily occur since fire-drive tail gas usually contains corrosive gases, such as CO2 and O2. In this work, the corrosion behavior of several 35CrMo steel samples in a fire-drive tail gas environment was studied using weightlessness measurements, surface characterization techniques, and high temperature-pressure electrochemical tests. The research results show that the average corrosion rate of 35CrMo steel in a CO2–O2 coexisting environment is much higher than the average corrosion rate in a CO2-containing environment or O2-containing environment. The localized corrosion rate of 35CrMo steel in an O2-containing environment is higher than the localized corrosion rate in both the case of a CO2-containing environment or a CO2–O2 one. The pitting factor shows that 35CrMo steel exhibits a localized corrosion in an O2-containing environment. The surface characterization results demonstrate that, in a typical fire-drive tail gas environment, the corrosion products are composed of Fe2O3, FeOOH, and Fe3O4. The high temperature-pressure electrochemistry test data shows that in a CO2–O2-oexisting environment, the membrane resistance decreases upon an increase in the O2 content.

Features of changes in the number and composition of the microbiome of the rhizosphere of winter wheat in the process of ontogeny

In agroecosystems, microorganisms are the main factor in the soil formation process, plant nutrition and phytosanitary condition of the soil. All measures aimed at restoring soil fertility and increasing productivity, environmental safety of agricultural production, are closely related to the activity of microorganisms. Increased local activity, biomass and diversity of microbiota are one of the most important characteristics that distinguish the rhizosphere from the total soil volume. The purpose of the research was to study the number and composition of the microbial complex of the rhizosphere of grain crops (winter wheat of different varieties of domestic selection) in the process of ontogenesis. To conduct a set of microbiological studies, soil samples (typical chernozem) were selected and prepared in compliance with standard requirements for sample preparation and storage in laboratory conditions. Analysis of rhizosphere soil samples was carried out on variants of different varieties of winter wheat of domestic selection. The number of soil microorganisms was determined by seeding suspensions on nutrient media according to generally accepted methods in microbiology. The determination of the total microbial biomass in the soil was carried out by the rehydration method, and the intensity of soil “breathing”, in terms of CO2 release and O2 absorption, was determined by the manometric method (Warburg apparatus). It was found that winter wheat varieties affected the formation of the microbiome of typical chernozem. The number and composition of the microbial complex of the rhizosphere of winter wheat in the process of ontogenesis changes significantly, especially in terms of the ratio of the number of spore-forming and non-spore forms of microorganisms under the same conditions of agricultural technology for growing crops. The rhizosphere's total pool of saprotrophic microorganisms shows biomass variability and changes in favour of ecoplastic bacilli. An increase in the number of spore-forming bacteria to 4.2 x 107 CFU/g was found in the variants of cultivation of certain varieties. Cultivation of different varieties of winter wheat demonstrates stable indicators of CO2 emission intensity – from 5.2 to 7.0. A similar trend can be traced in the absorption rate of O2 (no more than 5.3-6.8)

Effect of Pulsed Electromagnetic Field on Growth, Physiology and Postharvest Quality of Kale (Brassica oleracea), Wheat (Triticum durum) and Spinach (Spinacia oleracea) Microgreens

Microgreens’ popularity is increasing worldwide, and many efforts are focused on novel techniques that could increase fresh production without affecting the quality and the shelf life of the young plants. Three species of microgreens (kale, durum wheat, and spinach) were cultivated in a greenhouse experiment in November–December 2020. Pulsed electromagnetic field (PEMF) was applied at three different growth stages (seed, newly developed plant, and before harvest) and three different times of exposure at each stage, while untreated seeds were used as control. According to the results, certain PEMF treatments increased fresh weight for all three plant species, while dry weight was higher in the treated plants for wheat and spinach, compared to the control. As for the color parameters L*, a*, and b*, at the harvest and postharvest, PEMF treatments had no negative effects, either at harvest or at green color retention, during storage. Moreover, PEMF treatments improved green color in wheat, and restricted yellow color in spinach. An important finding regarding respiration was that PEMF treatments increased both O2 consumption and CO2 production for durum wheat and CO2 production for spinach.

Ultrathin CuNi Nanosheets for CO2 Reduction and O2 Reduction Reaction in Fuel Cells

Ultrathin CuNi Nanosheets for CO₂ Reduction and O₂ Reduction Reaction in Fuel Cells

Development of a kinetic model to describe six types of symbiotic interactions in a formate utilizing microalgae-bacteria cultivation system

This study investigated an algae/formate-utilizing-bacteria system that has been developed for carbon capture. This photomixotrophic consortium consumed formate to support bacterial growth so that the resulting respiration CO2 could be simultaneously used by algae to avoid CO2 gas-lipid mass transfer limitation. To understand biomass growth and population interactions in this unique system, a kinetic model has been developed to describe algae and bacteria multiplication, formate and nitrogen utilizations, CO2 mass transfer, O2 generation and consumption, lighting condition and shading effect. The simulation indicated that this ecosystem could form six types of interactions (mutualism, commensalism, parasitism, neutralism, amensalism, and competition) depending on the light intensity and nutrient availability. The simulation of both batch culture and chemostat, along with parameter sensitivity tests and experimental observations, offered insights into optimal applications of algae-bacteria consortium based photobiorefinery.

Anti-obesity effect and mechanism of mesenchymal stem cells influence on obese mice.

Mesenchymal stem cells (MSCs) can be obtained from almost all tissues and present promising therapeutic effects for metabolic diseases. Human adipose-derived MSCs (hASCs) have recently been widely studied due to their easy access and low immunity. Thus, we intended to figure out the effects and potential mechanism of hASCs on obesity in high-fat-diet (HFD)-induced obese mice. Following 16 weeks of being fed HFD, hASCs were intravenously injected. Two weeks later, body weight, body composition, and energy expenditure were evaluated. Additionally, the phenotypes of macrophages infiltrating adipose tissue were analyzed. The results revealed that hASCs administration significantly reduced adipose tissue weight, adipocyte size, and fat mass and exerted beneficial effects in serum lipid profile. This anti-obesity effect was mediated by the increased O2 consumption, CO2 production, and energy expenditure, which was further evidenced by the upregulation of uncoupling protein-1 (UCP-1) and metabolism-associated genes. Furthermore, hASCs infusion increased the amount of alternatively activated (M2) macrophages in adipose tissue, and the expression of pro-inflammatory cytokines-related genes was reduced. Taken together, these results indicated that hASCs suppressed obesity by increasing UCP-1 expression and enhancing energy expenditure, and this effect might be due to the increased M2 macrophages.

A combined mathematical model to represent transpiration, respiration, and water activity changes in fresh cape gooseberry (Physalis peruviana) fruits

In this work, a combined respiration and transpiration model is proposed for fresh cape gooseberry fruits, also considering changes in water activity (aw) and moisture content. Initially, a correlation of parameters was obtained from experimental data to determine the kinetics of O2 consumption and CO2 production for cape gooseberry fruits at different temperatures. From the data on the change in gas concentration, a parameter adjustment was made evaluating three kinetic models to represent respiration: 1) Power-Law Chemical kinetics (PL), 2) Simple Michaelis–Menten kinetics (MM), and 3) Michaelis–Menten with uncompetitive inhibition by CO2 (MMU). The temperature-dependence was considered in the three models by integrating an Arrhenius equation in the kinetic parameters. Afterward, a combined model was obtained to describe the fruit transpiration, coupling the moisture sorption isotherm (logistic model), and including the temperature-dependence and the most suitable respiration kinetics. It was determined that with the MMU kinetics it was possible to obtain a high goodness of fit with the experimental behaviour for the changes in the O2 and CO2 concentrations (R2adj. = 0.964 and 0.981). The MM kinetics had an acceptable fit (R2adj. = 0.940 and 0.941), while the PLK model could not explain the observed behaviour (R2adj. = 0.247 and 0.647). It was found that a logistic model appropriately described the relationship between the fruit moisture content and aw (R2adj. = 0.998). A close relationship was determined between the fruit's transpiration and its respiration rate, the change in the water activity, and the surrounding temperature and relative humidity (R2adj. = 0.998). As the temperature decreased, and as the relative humidity increased, the change in water activity and the transpiration rate decreased. Through the parameters established for each model, it is possible to predict the behaviour of processes such as respiration, transpiration, and changes in aw to configure a storage and packaging system by proposing the gas balance equations (O2, CO2, and water vapour) that allow obtaining favourable gas levels for the preservation of the fresh fruits.