Cell System Research Articles

Cell-cell contact-dependent secretion of large-extracellular vesicles from EFNBhigh cancer cells accelerates peritoneal dissemination.

Large non-apoptotic vesicles released from the plasma membrane protrusions are classified as large-EVs (LEVs). However, the triggers of LEV secretion and their functions in tumors remain unknown. Coculture system of cancer cells, peritoneal mesothelial cells (PMCs), and macrophages (MΦs) was conducted to observe cell-cell contact-mediated LEV secretion. Lineage tracing of PMCs was performed using Wt1CreERT2-tdTnu mice to explore the effects of LEVs on PMCs in vivo, and lymphangiogenesis was assessed by qRT-PCR and flow-cytometry. In peritoneal dissemination, cancer cells expressing Ephrin-B (EFNB) secreted LEVs upon the contact with PMCs expressing ephrin type-B (EphB) receptors, which degraded mesothelial barrier by augmenting mesothelial-mesenchymal transition. LEVs were incorporated in subpleural MΦs, and these MΦs transdifferentiated into lymphatic endothelial cells (LEC) and integrated into the lymphatic vessels. LEC differentiation was also induced in PMCs by interacting with LEV-treated MΦs, which promoted lymphangiogenesis. Mechanistically, activation of RhoA-ROCK pathway through EFNB reverse signaling induced LEV secretion. EFNBs on LEVs activated EphB forward signaling in PMC and MΦs, activating Akt, ERK and TGF-β1 pathway, which were indispensable for causing MMT and LEC differentiation. LEVs accelerated peritoneal dissemination and lymphatic invasions by cancer cells. Blocking of EFNBs on LEVs using EphB-Fc-fusion protein attenuated these events. EFNBhigh cancer cells scattered LEVs when they attached to PMCs, which augmented the local reactions of PMC and MΦ (MMT and lymphangiogenesis) and exaggerated peritoneal dissemination.

Genome-Wide Identification of APX Gene Family in Citrus maxima and Expression Analysis at Different Postharvest Preservation Times.

Ascorbate peroxidase (APX) is a crucial enzyme involved in cellular antioxidant defense and plays a pivotal role in modulating reactive oxygen species (ROS) levels under various environmental stresses in plants. This study utilized bioinformatics methods to identify and analyze the APX gene family of pomelo, while quantitative real-time PCR (qRT-PCR) was employed to validate and analyze the expression of CmAPXs at different stages of fruit postharvest. This study identified 96 members of the CmAPX family in the entire pomelo genome, with uneven distribution across nine chromosomes and occurrences of gene fragment replication. The subcellular localization includes peroxisome, cytoplasm, chloroplasts, and mitochondria. The CmAPX family exhibits a similar gene structure, predominantly consisting of two exons. An analysis of the upstream promoter regions revealed a significant presence of cis-acting elements associated with light (Box 4, G-Box), hormones (ABRE, TCA-element), and stress-related (MBS, LTR, ARE) responses. Phylogenetic and collinearity analyses revealed that the CmAPX gene family can be classified into three subclasses, with seven collinear gene pairs. Furthermore, CmAPXs are closely related to citrus, pomelo, and lemon, followed by Arabidopsis, and exhibit low homology with rice. Additionally, the transcriptomic heat map and qPCR results revealed that the expression levels of CmAPX57, CmAPX34, CmAPX50, CmAPX4, CmAPX5, and CmAPX81 were positively correlated with granulation degree, indicating the activation of the endogenous stress resistance system in pomelo cells by these genes, thereby conferring resistance to ROS. This finding is consistent with the results of GO enrichment analysis. Furthermore, 38 miRNAs were identified as potential regulators targeting the CmAPX family for post-transcriptional regulation. Thus, this study has preliminarily characterized members of the APX gene family in pomelo and provided valuable insights for further research on their antioxidant function and molecular mechanism.

Salinity-driven nitrogen removal and bacteria community compositions in microbial fuel cell-integrated constructed wetlands.

The effects of salinity gradients (500-4000mg·L-1 NaCl) on electricity generation, nitrogen removal, and microbial community were investigated in a constructed wetland-microbial fuel cell (CW-MFC) system. The result showed that power density significantly increased from 7.77 mW m-2 to a peak of 34.27 mW m-2 as salinity rose, indicating enhanced electron transfer capabilities under saline conditions. At a moderate salinity level of 2000mg·L-1 NaCl, the removal efficiencies of NH4+-N and TN reached their maximum at 77.34 ± 7.61% and 48.45 ± 8.14%, respectively. This could be attributed to increased microbial activity and the presence of critical nitrogen-removal organisms, such as Nitrospira and unclassified Betaproteobacteria at the anode, as well as Bacillus, unclassified Rhizobiales, Sphingobium, and Simplicispira at the cathode. Additionally, this salinity corresponded with the highest abundance of Exiguobacterium(3.92%), a potential electrogenic bacterium, particularly at the cathode. Other microorganisms, including Geobacter, unclassified Planctomycetaceae, and Thauera, adapted well to elevated salinity, thereby enhancing both electricity generation and nitrogen removal.

Pasteurized form of a potential probiotic lactobacillus brevis IBRC-M10790 exerts anti-inflammatory effects on inflammatory bowel disease in vitro

BackgroundInflammatory bowel disease (IBD) is a chronic, relapsing inflammatory disorder of the gastrointestinal system. So far, no treatment has been identified that can completely cure IBD. Lactobacillus brevis is hypothesized to be beneficial in preventing inflammation. This study aimed to evaluate the potential probiotic effects of live and pasteurized L. brevis IBRC-M10790 on the in vitro cell co-culture model of IBD.MethodsAn in vitro intestinal model was established using a transwell co-culture system of Caco-2 intestinal epithelial cells and RAW264.7 macrophages. Inflammatory conditions were induced in RAW264.7 cells using lipopolysaccharide. The effects of live and pasteurized L. brevis IBRC-M10790 on inflammatory mediators and epithelial barrier markers were investigated.ResultsL. brevis IBRC-M10790 was able to significantly decrease the proinflammatory cytokines (IL-6, IL-1β, and TNF-α) and increase the anti-inflammatory cytokine (IL-10) in the in vitro co-culture system. In addition, L. brevis increased adherens and tight junction (TJ) markers (ZO-1, E-cadherin, and Occludin) in Caco-2 intestinal epithelial cells. Based on the results, pasteurized L. brevis showed a higher protective effect than live L. brevis.ConclusionsOur findings suggest that live and pasteurized forms of L. brevis possess probiotic properties and can mitigate inflammatory conditions in IBD.

Pasteurized form of a potential probiotic lactobacillus brevis IBRC-M10790 exerts anti-inflammatory effects on inflammatory bowel disease in vitro

BackgroundInflammatory bowel disease (IBD) is a chronic, relapsing inflammatory disorder of the gastrointestinal system. So far, no treatment has been identified that can completely cure IBD. Lactobacillus brevis is hypothesized to be beneficial in preventing inflammation. This study aimed to evaluate the potential probiotic effects of live and pasteurized L. brevis IBRC-M10790 on the in vitro cell co-culture model of IBD.MethodsAn in vitro intestinal model was established using a transwell co-culture system of Caco-2 intestinal epithelial cells and RAW264.7 macrophages. Inflammatory conditions were induced in RAW264.7 cells using lipopolysaccharide. The effects of live and pasteurized L. brevis IBRC-M10790 on inflammatory mediators and epithelial barrier markers were investigated.ResultsL. brevis IBRC-M10790 was able to significantly decrease the proinflammatory cytokines (IL-6, IL-1β, and TNF-α) and increase the anti-inflammatory cytokine (IL-10) in the in vitro co-culture system. In addition, L. brevis increased adherens and tight junction (TJ) markers (ZO-1, E-cadherin, and Occludin) in Caco-2 intestinal epithelial cells. Based on the results, pasteurized L. brevis showed a higher protective effect than live L. brevis.ConclusionsOur findings suggest that live and pasteurized forms of L. brevis possess probiotic properties and can mitigate inflammatory conditions in IBD.

Self-Aerated Osmotic Microbial Fuel Cell System Based on Siphon Principle: Performance Investigation and Application Significance

Self-Aerated Osmotic Microbial Fuel Cell System Based on Siphon Principle: Performance Investigation and Application Significance

A cell-based fluorescent system and statistical framework to detect meiosis-like induction in plants.

Genetic gains made by plant breeders are limited by generational cycling rates and flowering time. Several efforts have been made to reduce the time to switch from vegetative to reproductive stages in plants, but these solutions are usually species-specific and require flowering. The concept of in vitro nurseries is that somatic plant cells can be induced to form haploid cells that have undergone recombination (creating artificial gametes), which can then be used for cell fusion to enable breeding in a Petri dish. The induction of in vitro meiosis, however, is the largest current bottleneck to in vitro nurseries. To help overcome this, we previously described a high-throughput, bi-fluorescent, single cell system in Arabidopsis thaliana, which can be used to test the meiosis-like induction capabilities of candidate factors. In this present work, we validated the system using robust datasets (>4M datapoints) from extensive simulated meiosis induction tests. Additionally, we determined false-detection rates of the fluorescent cells used in this system as well as the ideal tissue source for factor testing.

Long-Term Continuous Gas Diagnostics For Fuel Cell Systems: Development Of An Automatized Raman Metrology

Long-Term Continuous Gas Diagnostics For Fuel Cell Systems: Development Of An Automatized Raman Metrology

Rotordynamics of a rotor supported by foil bearings under various housing excitation

Proton Exchange Membrane (PEM) Fuel cell Systems(FCS) are rapid-growing technology in transportation systems. In such applications, a motor-driven oil-free air compressor is one of the critical auxiliary subsystems. Foil bearings are the perfect choice as oil-free bearings for the compressors due to high rotordynamics stability and shock-resistance. The platform of a motor-driven oil-free compressor can also be used as an electric turbocharger for traditional internal combustion engines. All electromechanical subsystems for electric vehicles must satisfy vibration endurance requirements following ISO 16750–3:2012, characterized by certain g-loading at specific frequencies. For the compressor to satisfy ISO 16750 requirement, detailed rotordynamics simulations with externally excited compressor housing under certain g-loading are essential to design the foil bearings considering the static and dynamic loads to the bearing and rotordynamics stability. The main objectives of the current research are 1) to develop a four degree of freedom (4-DOF) dynamic model of the rotor supported by foil bearings under external excitation to the compressor, 2) to simulate linear and non-linear rotordynamics of the compressor rotor supported by two radial foil bearings, and 3) to provide appropriate design guideline such as bump stiffness and axial length of the foil bearings. The simulations show that the rotor is stable for both under single frequency excitation and simultaneous excitations of all the frequencies in ISO 17650 standard. 4-DOF modal analyses were applied to identify natural mode of the system under the housing excitation.

PROTAC<sup>®</sup> technology and potential for its application in infection control

Objectives. To describe the pharmaceutical technology of controlled degradation of protein molecules (PROTAC®, Proteolysis Targeting Chimera), approaches to the design of the PROTAC® molecule, methods of ligand and linker selection and synthesis, as well as the application of this technology in dealing with a variety of diseases and the possible limitations of its use.Results. The review covers 77 sources, mostly from 2020–2023. The review outlines the principle of PROTAC® technology: the construction of a chimeric molecule consisting of three fragments. One fragment specifically binds to the biotarget, another recruits the proteolytic system of the host cell, and the third binds them together. The main areas of the current development of the technology are described herein, as well as the opportunities and limitations of chimeric molecules in the fight against different types of infectious diseases.Conclusion. The potential to use PROTAC® technology to combat cancer as well as neurodegenerative, autoimmune, and infectious diseases is shown.

Comprehensive characterization of the neurogenic and neuroprotective action of a novel TrkB agonist using mouse and human stem cell models of Alzheimer’s disease

BackgroundNeural stem cell (NSC) proliferation and differentiation in the mammalian brain decreases to minimal levels postnatally. Nevertheless, neurogenic niches persist in the adult cortex and hippocampus in rodents, primates and humans, with adult NSC differentiation sharing key regulatory mechanisms with development. Adult neurogenesis impairments have been linked to Alzheimer’s disease (AD) pathology. Addressing these impairments by using neurotrophic factors is a promising new avenue for therapeutic intervention based on neurogenesis. However, this possibility has been hindered by technical difficulties of using in-vivo models to conduct screens, including working with scarce NSCs in the adult brain and differences between human and mouse models or ethical limitations.MethodsHere, we use a combination of mouse and human stem cell models for comprehensive in-vitro characterization of a novel neurogenic compound, focusing on the brain-derived neurotrophic factor (BDNF) pathway. The ability of ENT-A011, a steroidal dehydroepiandrosterone derivative, to activate the tyrosine receptor kinase B (TrkB) receptor was tested through western blotting in NIH-3T3 cells and its neurogenic and neuroprotective action were assessed through proliferation, cell death and Amyloid-β (Aβ) toxicity assays in mouse primary adult hippocampal NSCs, mouse embryonic cortical NSCs and neural progenitor cells (NPCs) differentiated from three human induced pluripotent stem cell lines from healthy and AD donors. RNA-seq profiling was used to assess if the compound acts through the same gene network as BDNF in human NPCs.ResultsENT-A011 was able to increase proliferation of mouse primary adult hippocampal NSCs and embryonic cortical NSCs, in the absence of EGF/FGF, while reducing Aβ-induced cell death, acting selectively through TrkB activation. The compound was able to increase astrocytic gene markers involved in NSC maintenance, protect hippocampal neurons from Αβ toxicity and prevent synapse loss after Aβ treatment. ENT-A011 successfully induces proliferation and prevents cell death after Aβ toxicity in human NPCs, acting through a core gene network shared with BDNF as shown through RNA-seq.ConclusionsOur work characterizes a novel BDNF mimetic with preferable pharmacological properties and neurogenic and neuroprotective actions in Alzheimer’s disease via stem cell-based screening, demonstrating the promise of stem cell systems for short-listing competitive candidates for further testing.

Hydroxytyrosol permeability comparisons and strategies to improve hydroxytyrosol stability in formulations

There has been a growing interest in hydroxytyrosol (HT) due to its powerful antioxidant and free-radical scavenging properties when added to formulations such as pharmaceuticals and cosmetics. To study the stability and transdermal properties of hydrogels and creams (HT-based formulations), a high-performance liquid chromatography method was developed for determining HT. In the Franz diffusion cell system, both hydrogel and cream show a rapid and similar penetration profile through the Bama miniature pig skin. However, the Strat-M® membrane exhibits slightly lower permeability and is selective to different formulations; that is, the cream has a permeability value of 10.69%, while the hydrogel has a value of 5.27%. The dynamics parameters from the permeation assays indicate that the model using the Strat-M® membrane can be used as a screening tool to evaluate the skin uptake and permeation efficacy of different formulations. Adding 3-O-ethyl-L-ascorbic acid to HT-based formulations can effectively prevent discoloration under prolonged high-temperature storage, while combining multiple antioxidants delays degradation most effectively. This study provides novel ideas for functional formulation optimization to enhance the realism and reproducibility of cosmetic products containing HT and provides scientific evidence for the production, packaging, shelf life, storage, and transportation of products.

An Indirect Ammonia Fuelled Solid-Oxide Fuel Cell System with free cracking from Waste Heat

An Indirect Ammonia Fuelled Solid-Oxide Fuel Cell System with free cracking from Waste Heat

Des-acyl ghrelin reduces alcohol intake and alcohol-induced reward in rodents

The mechanisms contributing to alcohol use disorder (AUD) are complex and the orexigenic peptide ghrelin, which enhances alcohol reward, is implied as a crucial modulator. The major proportion of circulating ghrelin is however the non-octanoylated form of ghrelin, des-acyl ghrelin (DAG), whose role in reward processes is unknown. As recent studies show that DAG decreases food intake, we hypothesize that DAG attenuates alcohol-related responses in animal models. Acute and repeated DAG treatment dose-dependently decreased alcohol drinking in male and female rats. In these alcohol-consuming male rats, repeated DAG treatment causes higher levels of dopamine metabolites in the ventral tegmental area, an area central to reward processing. The role of DAG in reward processing is further supported as DAG prevents alcohol-induced locomotor stimulation, reward in the conditioned place preference paradigm, and dopamine release in the nucleus accumbens in male rodents. On the contrary, DAG does not alter the memory of alcohol reward or affect neurotransmission in the hippocampus, an area central to memory. Further, circulating DAG levels are positively correlated with alcohol drinking in female but not male rats. Studies were conducted in attempts to identify tentative targets of DAG, which currently are unknown. Data from these recombinant cell system revealed that DAG does not bind to either of the monoamine transporters, 5HT2A, CB1, or µ-opioid receptors. Collectively, our data show that DAG attenuates alcohol-related responses in rodents, an effect opposite to that of ghrelin, and contributes towards a deeper insight into behaviors regulated by the ghrelinergic signaling pathway.

High Ammonia Yield Rate from Dilute Nitrate Solutions Using a Cu(100)-Rich Foil: A Step Closer to Large-Scale Production.

The electrochemical reduction of nitrate (NO3-) ions to ammonia (NH3) provides an alternative method to eliminate harmful NO3- pollutants in water as well as to produce highly valuable NH3 chemicals. The NH3 yield rate however is still limited to the μmol h-1 cm-2 range when dealing with dilute NO3- concentrations found in waste streams. Copper (Cu) has attracted much attention because of its unique ability to effectively convert NO3- to NH3. We have reported a simple and scalable electrochemical method to produce a Cu foil having its surface covered with a porous Cu nanostructure enriched with (100) facets, which efficiently catalyzes NO3- to NH3. The Cu(100)-rich electrocatalyst showed a very high NH3 production rate of 1.1 mmol h-1 cm-2 in NO3- concentration as low as 14 mM NO3-, which is 4-5 times higher than the best-reported values. Increasing the NO3- concentration (140 mM) resulted in an NH3 production yield rate of 3.34 mmol h-1 cm-2. The durability test conducted for this catalyst foil in a flow cell system showed greater than 100 h stability with a Faradaic efficiency greater than 98%, demonstrating its potential to be used on an industrially relevant scale. Further, density functional theory (DFT) calculations have been performed to understand the better catalytic activity of Cu(100) compared to Cu(111) facets toward NO3-RR.

P-678 Cabergoline has inhibitory effects on FSH-induced cell differentiation and estrogen secretion in a primary culture system of rat ovarian granulosa cells

Abstract Study question How does cabergoline have effects on cell differentiation and hormone secretion induced by FSH stimulation in ovarian granulosa cells? Summary answer Cabergoline suppresses LH receptor expression and Estradiol (E2) secretion in primary cultures of rat ovarian granulosa cells by inhibiting cAMP production induced by FSH stimulation. What is known already Cabergoline is a dopamine receptor 2 agonist that has been used to treat hyperprolactinemia and, more recently, to prevent ovarian hyperstimulation syndrome. Although it has been previously reported that cabergoline suppresses E2 and Progesterone secretion induced by FSH stimulation in a primary culture system of rat ovarian granulosa cells, but the effect on LH receptor expression has not been investigated. It has also been reported that the activation of dopamine receptor 2 suppresses VEGF secretion and reduces the incidence of early-onset OHSS by inhibiting the VEGF/VEGFR2 pathway in research using human luteinized granulosa cells. Study design, size, duration We used a primary culture system of ovarian granulosa cells obtained from immature female rats treated with diethylstilbestrol to examine the effect of cabergoline addition on the changes in ovarian granulosa cells induced by FSH stimulation. Participants/materials, setting, methods FSH and cabergoline were added alone or co-added to a primary culture system of rat ovarian granulosa cells, and the changes induced by them were measured and compared. (1) mRNA expression of Lhcgr, Cyp19a1, and Fshr by RT-qPCR (2) E2 concentration in the culture medium (3) Measurement of hCG binding on the cell surface (4) cAMP concentration Main results and the role of chance Co-addition of cabergoline suppressed each of the changes induced by FSH stimulation as follows. (1) The mRNA expression levels of Lhcgr, Cyp19a1, and Fshr decreased in a concentration-dependent manner (0.01-10 µM) of co-added cabergoline compared to FSH alone. In the 10 µM of co-added cabergoline group, they decreased to 14%, 9%, and 49% of FSH alone, respectively. (2) E2 concentration in the culture media also decreased in a concentration-dependent manner (1-10 µM) of co-added cabergoline compared to FSH alone. In the 10 µM of co-added cabergoline group, it decreased to 49% of FSH alone. (3) The amount of hCG binding on the cell surface also decreased in a concentration-dependent manner (0.1-10 µM) of co-added cabergoline compared to FSH alone. In the 10 µM of co-added cabergoline group, it decreased to 7% of FSH alone. (4) FSH-stimulated cAMP production decreased in a concentration-dependent manner (0.01-1µM) of co-added cabergoline compared to FSH alone. In the 1µM of co-added cabergoline group, it decreased to 50% of FSH alone. These results suggest that cabergoline suppresses LH receptor and aromatase expression and E2 production by inhibiting cAMP production induced by FSH stimulation. Limitations, reasons for caution Since this is an in vitro experiment using a rat primary culture system, the results of this research cannot be considered directly applicable to humans. Wider implications of the findings Our findings imply that cabergoline administration during the follicular phase may inhibit ovarian granulosa cell differentiation and estrogen secretion. In women taking relatively high doses of cabergoline, attention may need to be paid regarding the effects of cabergoline on follicular development and estrogen secretion. Trial registration number not applicable

O-070 Cas9-based chromosome labelling reveals large-scale age-dependent centromere reorganisation in human oocytes

Abstract Study question Can centromeres be labelled in live human oocytes using Cas9 system and is the labelling efficiency affected by advancing female age? Summary answer Centromeres in human oocytes can be labelled using Cas9 system. Signal intensity decreases in oocytes from older patients, suggesting centromeric DNA unravelling as oocytes age. What is known already Aneuploidy in human oocytes is associated with infertility, pregnancy loss or genetic diseases in offspring. It arises due to abnormal chromosome segregation during meiosis, with the risk increasing with advancing female age. This is attributed to age-dependent loss of pericentromere-localised cohesion which holds sister chromatids together. Our work revealed that shugoshin-2 (Sgo2), a protein involved in protection of sister chromatid cohesion is also lost with age. This can exacerbate the effects of maternal age by rendering residual cohesin at pericentromeres vulnerable to loss in anaphase I. This hints at more extensive alterations to centromere organisation with advanced maternal age. Study design, size, duration This study uses human oocytes deselected from fertility treatment donated for research purposes with informed consent (HFEA RO155). The oocytes were collected fresh at germinal vesicle (GV), metaphase I (MI) or metaphase II (MII) stage, injected with Cas9 labelling system and live imaged or fixed. Participants/materials, setting, methods Centromeres were labelled in human oocytes using a dead (nuclease-deficient) (d)Cas9-EGFP protein and alpha satellite-specific small guide RNAs (sgRNA). Human oocytes were injected with dCas9-EGFP:sgAlphaSat and live-imaged using dual colour confocal microscopy with SPY555-DNA dye to also visualise chromosomes. High resolution imaging results were analysed with in-house automated kinetochore tracking software. Additional oocytes were fixed and processed for immunofluorescence to determine the high resolution localisation of dCas9-EGFP:sgAlphaSat and Sgo2 molecules. Main results and the role of chance We found that centromeres in human oocytes are efficiently labelled when using Cas9 system. During both meiosis I and II the dCas9-EGFP:sgAlphaSat probe co-localised with pericentromeric bridge and subcentromeric pools of Sgo2. We observed that the dCas9-EGFP:sgAlphaSat signal fades with advancing female age. Quantification reveals that in meiosis II the loss is abrupt at around 35 years of age, resembling Sgo2 behaviour. Initial live imaging indicates that already compromised signal in older oocytes is completely lost about 4hrs after germinal vesicle breakdown, suggesting that advancing age renders centromeres more vulnerable as meiosis I progresses. We have successfully tracked the centromeres in high resolution imaging using the automated software, which allows for detailed investigation of human meiosis chromosome dynamics. This method has been previously validated and successfully used for other cell systems. Limitations, reasons for caution Availability of human oocytes for research purposes is low, limiting our sample size. Moreover, most oocytes used for this study were deselected from treatment of patients diagnosed with infertility, potentially affecting their quality. Wider implications of the findings Our results reveal a large-scale change in centromeric DNA structure in human oocytes with increasing age. Live centromere labelling is a first successful attempt to bivalent tracking in human meiosis with potential to provide insight into age-related loss of fertility in women. Trial registration number n/a

Enhancing the efficiency of photovoltaic cells through the usage of dye concentrators

Over the past few years, there has been a growing interest in renewable energy sources. Among them, photovoltaic (PV) technology is advancing rapidly. Solar insolation is the most crucial factor for PV installations. Various solutions, such as tracking mechanisms, hybrid systems, and new materials, can enhance the efficiency of PV systems. Concentrators focus solar light onto the surface of solar modules, increasing production of electricity. Implementing such solutions can reduce the number of silicon cells in installations, leading to a decrease in waste generated during production. Dye concentrators have a positive impact on the performance of silicon systems. A two-stage study on the effect of dye concentrator application on PV cell efficiency is carried out. In the first stage, specific types of dye concentrators are tested for their interaction with the silicon system. Tinted and luminescent acrylic glass (polymethyl methacrylate, PMMA) in yellow and red are used as dye concentrators. The experiment included multiple measurement calibrations, such as the temperature of the tested silicon cell and the intensity of illuminance. Results showed absolute increase of efficiency in solar cells ranging from 0.05% to 1.42%, depending on the type of concentrator used. The most significant improvements were observed with luminescent red PMMA, averaging at 1.21%. The potential of this concentrator was further explored in the second stage of the study, investigating the relationship between the surface involvement of the silicon cell and the dye concentrator. Test results indicated the potential of dye concentrators for integrating luminescent dye concentrator technology into PV systems. The effect of this integration is increase in the efficiency of the PV cell. On the other hand, it should be noted that replacing the PV cell with a dye concentrator reduces the efficiency of the entire photovoltaic system. Hence, the use of a PV cell and concentrator system is recommended especially for photovoltaic systems with a large area. As dye concentrators have the ability to operate without direct irradiance, they are also recommended for regions where natural light is dispersed.

Energy Consumption and Saved Emissions of a Hydrogen Power System for Ultralight Aviation: A Case Study

The growing concern about climate change and the contemporary increase in mobility requirements call for faster, cheaper, safer, and cleaner means of transportation. The retrofitting of fossil-fueled piston engine ultralight aerial vehicles to hydrogen power systems is an option recently proposed in this direction. The goal of this investigation is a comparative analysis of the environmental impact of conventional and hydrogen-based propulsive systems. As a case study, a hybrid electric configuration consisting of a fuel cell with a nominal power of about 30 kW, a 6 kWh LFP battery, and a pressurized hydrogen vessel is proposed to replace a piston prop configuration for an ultralight aerial vehicle. Both power systems are modeled with a backward approach that allows the efficiency of the main components to be evaluated based on the load and altitude at every moment of the flight with a time step of 1 s. A typical 90 min flight mission is considered for the comparative analysis, which is performed in terms of direct and indirect emissions of carbon dioxide, water, and pollutant substances. For the hydrogen-based configuration, two possible strategies are adopted for the use of the battery: charge sustaining and charge depleting. Moreover, the effect of the altitude on the parasitic power of the fuel cell compressor and, consequently, on the net efficiency of the fuel cell system is taken into account. The results showed that even if the use of hydrogen confines the direct environmental impact to the emission of water (in a similar quantity to the fossil fuel case), the indirect emissions associated with the production, transportation, and delivery of hydrogen and electricity compromise the desired achievement of pollutant-free propulsion in terms of equivalent emissions of CO2 and VOCs if hydrogen is obtained from natural gas reforming. However, in the case of green hydrogen from electrolysis with wind energy, the total (direct and indirect) emissions of CO2 can be reduced up to 1/5 of the fossil fuel case. The proposed configuration has the additional advantage of eliminating the problem of lead, which is used as an additive in the AVGAS 100LL.

Stable Production of a Recombinant Single-Chain Eel Follicle-Stimulating Hormone Analog in CHO DG44 Cells.

This study aimed to produce single-chain recombinant Anguillid eel follicle-stimulating hormone (rec-eel FSH) analogs with high activity in Cricetulus griseus ovary DG44 (CHO DG44) cells. We recently reported that an O-linked glycosylated carboxyl-terminal peptide (CTP) of the equine chorionic gonadotropin (eCG) β-subunit contributes to high activity and time-dependent secretion in mammalian cells. We constructed a mutant (FSH-M), in which a linker including the eCG β-subunit CTP region (amino acids 115-149) was inserted between the β-subunit and α-subunit of wild-type single-chain eel FSH (FSH-wt). Plasmids containing eel FSH-wt and eel FSH-M were transfected into CHO DG44 cells, and single cells expressing each protein were isolated from 10 and 7 clones. Secretion increased gradually during the cultivation period and peaked at 4000-5000 ng/mL on day 9. The molecular weight of eel FSH-wt was 34-40 kDa, whereas that of eel FSH-M increased substantially, with two bands at 39-46 kDa. Treatment with PNGase F to remove the N glycosylation sites decreased the molecular weight remarkably to approximately 8 kDa. The EC50 value and maximal responsiveness of eel FSH-M were approximately 1.23- and 1.06-fold higher than those of eel FSH-wt, indicating that the mutant showed slightly higher biological activity. Phosphorylated extracellular-regulated kinase (pERK1/2) activation exhibited a sharp peak at 5 min, followed by a rapid decline. These findings indicate that the new rec-eel FSH molecule with the eCG β-subunit CTP linker shows potent activity and could be produced in massive quantities using the stable CHO DG44 cell system.