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Nanopore protein (α-hemolysin) was used to detect sub-nanosized plastic particles leached from a PE-coated paper cup. These sub-nanosized plastic particles can increase the inflammation response of macrophages. [Display omitted] • Nanopore sensing detects sub-nanosized plastics in PE-coated paper cups. • Sub-nanosized plastic particles in paper cups were 1.8 times more detected in boiled water than in room temperature water. • Sub-nanosized and microplastic particles alter cell membrane dynamics. • Sub-nanosized plastic particles can induce inflammatory cell responses. In recent years, there has been growing global concern about environmental pollution, and the increasing use of plastic products has made microplastics a serious environmental pollutant worldwide. Accordingly, the development of microplastic detection methods and research on the harmful effects of microplastics on human health are being actively pursued. In this study, we detected particle leaching from PE-coated paper cups using label-free nanopore sensing to identify and quantify the presence of sub-nanosized plastic particles. Plastic particles leached from the paper cups were classified as < 1 nm and > 1 nm, and their interactions with artificial cell membranes and inflammatory responses in the cells were evaluated. The results demonstrated that in a commonly used paper cup, particles < 1.4 nm were present at a concentration of approximately 1.13 mM in hot water and 0.62 mM in room-temperature water. It was demonstrated that plastic particles < 1 nm could condense the artificial cell membrane, whereas particles > 1 nm could thicken the artificial cell membrane. Furthermore, both size ranges of particles leached from the paper cups triggered an inflammatory response in the cells, with the inflammatory response increasing in proportion to the concentration and treatment time. The detection and analysis revealed the presence of sub-nanosized plastic particles in PE-coated paper cups, which are commonly used in daily life. These particles pose health threats and contribute to environmental pollution. [ABSTRACT FROM AUTHOR]

Magnesium oxide nanoparticles (MgO NPs) have attracted considerable interest as antimicrobial agents in a wide variety of applications. We report a simple synthetic route towards MgO NPs (average diameter 10 nm) possessing potent antibacterial activity against both Gram-negative and Gram-positive bacteria. Detailed electron microscopy studies show how these particles induce oxidative stress, cell membrane leakage and cell death in bacteria at low NP concentrations, but remain non-toxic to eukaryotic cells. Applying a homogeneous dispersion of these nanoparticles on 18th century paper proved to be a highly effective means of preventing bacterial colonisation without altering the appearance of the paper samples, thus opening the doors to the use of these colourless, low-cost, and scalable nanoparticles for preventing biodeterioration in a range of paper-based objects and surfaces. • Nano-magnesium oxide particles (MgO NPs) of average size of around 10 nm have been synthesised using a simple one-pot synthesis. • The MgO NPs offer potent bactericidal activity but are non-toxic to mammalian cells at the same concentrations. • A combination of electron microscopy techniques shows how these nanoparticles produce oxidative stress, followed by cell membrane leakage and death. • The MgO NPs prevented bacterial colonisation of 18th century papers from the Archives of the Spanish Royal Botanic Garden. [ABSTRACT FROM AUTHOR]

A novel colorimetric/fluorescence bimodal lab-on-paper cyto-device was fabricated based on concanavalin A (Con A)-integrating multibranched hybridization chain reaction (mHCR). The product of mHCR was modified PtCu nanochains (colorimetric signal label) and graphene quantum dot (fluorescence signal label) for in situ and dynamically evaluating cell surface N-glycan expression. In this strategy, preliminary detection was carried out through colorimetric method, if needed, then the fluorescence method was applied for a precise determination. Au-Ag-paper devices increased the surface areas and active sites for immobilizing larger amount of aptamers, and then specifically and efficiently captured more cancer cells. Moreover, it could effectively reduce the paper background fluorescence. Due to the specific recognition of Con A with mannose and the effective signal amplification of mHCR, the proposed strategy exhibited excellent high sensitivity for the cytosensing of MCF-7 cells ranging from 100 to 1.0×10 7 and 80-5.0×10 7 cells mL −1 with the detection limit of 33 and 26 cells mL −1 for colorimetric and fluorescence, respectively. More importantly, this strategy was successfully applied to dynamically monitor cell-surface multi-glycans expression on living cells under external stimuli of inhibitors as well as for N-glycan expression inhibitor screening. These results implied that this biosensor has potential in studying complex native glycan-related biological processes and elucidating the N-glycan-related diseases in biological and physiological processes. [ABSTRACT FROM AUTHOR]

A number of life-saving drugs require therapeutic drug monitoring (TDM) for safe and effective use. Currently, however, TDM is performed using sophisticated analytical techniques relegated to central labs, increasing the cost per test and time to answer. Here, using a novel vertical flow membrane system with inkjet-printed surface enhanced Raman sensors, along with a portable spectrometer, we demonstrate a low cost and easy to use device to quantify levels of flucytosine, an antifungal that requires TDM for effective patient care, from undiluted human serum. To our knowledge, this work represents the first report of a passive vertical flow sample cleanup method with surface enhanced Raman detection. We first investigated and optimized the parameters of the vertical flow system for the detection of flucytosine in spiked serum samples. Then, using an optimized vertical-flow system utilizing nitrocellulose membranes and a paper SERS sensor, we achieved detection of down to 10 μg mL −1 flucytosine in undiluted serum, with quantitative detection across the entire therapeutic range. This system reduces the assay time to about 15 min, far quicker than the current gold standards. We anticipate that this novel system will enable near-patient therapeutic drug monitoring, leading to the safe and effective administration of a number of life-saving drugs. Furthermore, it will spawn the development of SERS detection systems capable of separating target analytes from real-world biological matrices. [ABSTRACT FROM AUTHOR]

For the diabetes diagnosis, noninvasive methods are preferred to invasive methods; urine glucose measurement is an example of a noninvasive method. However, conventional noninvasive methods for urine glucose measurement are not intuitive. Furthermore, such methods exhibit low selectivity because they can detect interfering molecules in addition to glucose. Herein, we fabricate a noninvasive, intuitive, and highly selective paper sensor consisting of polyaniline nanoparticles (PAni-NPs) and red blood cell membranes (RBCMs). The PAni-NPs (adsorbed on the paper) are highly sensitive to hydrogen ions and change color from emeraldine blue to emeraldine green within a few seconds. The RBCM (coated on the PAni-NP-adsorbed paper) having the glucose transporter-1 protein plays the role of a smart filter that transports glucose but rejects other interfering molecules. In particular, the selectivity of the RBCM-coated PAni-NP-based paper sensor was approximately improved ∼85%, compared to the uncoated paper sensors. The paper sensor could detect urine glucose over the range of 0–10 mg/mL (0–56 mM), with a limit of detection of 0.54 mM. The proposed paper sensor will facilitate the development of a highly selective and colorimetric urine glucose monitoring system. [Display omitted] • A highly selective paper-based sensor was fabricated for noninvasive urine glucose detection. • PAni-NP-functionalized cellulose paper was coated with a cell membrane to enhance selectivity. • RBCM prevents interfering molecules from approaching GOx, whereas GLUT-1 in RBCM selectively transports glucose to GOx. • PAni and RPAni paper sensors can be a useful technique for early detection of diabetes and rapid screening of glucose. [ABSTRACT FROM AUTHOR]

Abstract: Rapid signaling of estrogen involves membrane estrogen receptors (ERs), including membrane subpopulations of ERα and ERβ. In the mid-1990s, several laboratories independently reported the cloning of an orphan G protein-coupled receptor from vascular and cancer cells that was named GPR30. Research published between 2000 and 2005 provided evidence that GPR30 binds and signals via estrogen indicating that this intracellular receptor is involved in rapid, non-genomic estrogen signaling. The receptor has since been designated as the G protein-coupled estrogen receptor (GPER) by the International Union of Pharmacology. The availability of genetic tools such as different lines of GPER knock-out mice, as well as GPER-selective agonists and antagonists has advanced our understanding, but also added some confusion about the new function of this receptor. GPER not only binds estrogens but also other substances, including SERMs, SERDs, and environmental ER activators (endocrine disruptors; xenoestrogens) and also interacts with other proteins. This article represents a summary of a lecture given at the 7th International Meeting on Rapid Responses to Steroid Hormones in September 2011 in Axos, Crete, and reviews the current knowledge and questions about GPER-dependent signaling and function. Controversies that have complicated our understanding of GPER, including interactions with human ERα-36 and aldosterone as a potential ligand, will also be discussed. [Copyright &y& Elsevier]

The present work describes a unique method for the purification and concentration of catechins from Camellia sinensis. The extracted plant products after using hot waterwere filtered and fed into a membrane separation process to separate catechins. Samples collected at various stages of processing were filtered through an ordinary filter paper and used for HPLC analysis. The permeate flux increased from 9.23 x 10-6 to 17.8 x 10-6 m³ m-2 s-1 when cross flow velocity increased from 2 to 6 LPM at 30 Psi pressure. Aqueous permeate obtained from the membrane cell was concentrated and decaffeinated to get purified catechins. Combining all the catechin compounds a final product containing 72% of catechins was obtained. The catechins thus extracted were utilized in the preparation of a pharmaceutical supplement comprising an effective amount of 30-80% (w/w) catechin component mixture and 5-50% (w/w) starch as filler along with/without the inert materials as additives. [ABSTRACT FROM AUTHOR]

Cholesterol is an essential component of cell membranes and serves as an important precursor of steroidal hormones and bile acids, but elevated levels of cholesterol and its oxidation products have been accepted as a risk factor for maintenance of health. The free and ester forms of cholesterol and fatty acids are the two major biological lipids. The aim of this hypothesis paper is to address the long-standing dogma that cholesterol is less susceptible to free radical peroxidation than polyunsaturated fatty acids (PUFAs). It has been observed that cholesterol is peroxidized much slower than PUFAs in plasma but that, contrary to expectations from chemical reactivity toward peroxyl radicals, cholesterol appears to be more readily autoxidized than linoleates in cell membranes. The levels of oxidation products of cholesterol and linoleates observed in humans support this notion. It is speculated that this discrepancy is ascribed to the fact that cholesterol and phospholipids bearing PUFAs are localized apart in raft and non-raft domains of cell membranes respectively and that the antioxidant vitamin E distributed predominantly in the non-raft domains cannot suppress the oxidation of cholesterol lying in raft domains which are relatively deficient in antioxidant. [Display omitted] • Cholesterol and phospholipid linoleates, the two major lipids, are oxidized by enzymatic and non-enzymatic mechanisms. • Cholesterol hydroperoxides are produced exclusively by free radical and singlet oxygen oxidation. • Different from plasma, cholesterol is more readily oxidized than linoleates in cell membranes. • Cholesterol lying in lipid rafts might not be well protected by a-tocopherol compared with PUFAs which lie in non-raft domains. [ABSTRACT FROM AUTHOR]

We have previously shown that exposure to TiO 2 nanoparticles (NPs) reduces the resistance of HeLa cells to bacterial infection. Here we demonstrate that the increased infectivity is associated with enhanced asymmetry in the cholesterol distribution. We applied a live cell imaging method which uses tunable orthogonal cholesterol sensors to visualize and quantify in-situ cholesterol distribution between the two leaflets of the plasma membrane (PM). In the control culture, we found marked transbilayer asymmetry of cholesterol, with the concentration in the outer plasma membrane (OPM) being 13 ± 2-fold higher than that in the inner plasma membrane (IPM). Exposure of the culture to 0.1 mg/mL of rutile TiO 2 NPs increased the asymmetry such that the concentration in the OPM was 51 ± 10 times higher, while the total cholesterol content increased only 21 ± 2%. This change in cholesterol gradient may explain the increase in bacterial infectivity in HeLa cells exposed to TiO 2 NPs since many pathogens, including Staphylococcus aureus used in the present study, require cholesterol for proper membrane attachment and virulence. RT-PCR indicated that exposure to TiO 2 was responsible for upregulation of the ABCA1 and ABCG1 mRNAs, which are responsible for the production of the cholesterol transporter proteins that facilitate cholesterol transport across cellular membranes. This was confirmed by the observation of an overall decrease in bacterial infection in ABCA1 knockout or methyl-β-cyclodextrin-treated HeLa cells, as regardless of TiO 2 NP exposure. Hence rather than preventing bacterial infection, TiO 2 nanoparticles upregulate genes associated with membrane cholesterol production and distribution, hence increasing infectivity. A great deal of work has been done regarding the toxicology of the particles, especially focusing on detrimental outcomes associated with reactive oxygen species (ROS) production. In this paper we show unambiguously a very surprising result, namely the ability of these particles to enhance bacterial infection even at very small exposure levels, where none of the deleterious effects of ROS products can yet be detected. Using a new imaging technique, we are able to demonstrate, in operando, the effect of the particles on cholesterol generation and distribution in live HeLa cells. This paper also represents the first in a series where we explore other consequences of increased membrane cholesterol, due to particle exposure, which are known to have multiple other consequences on human tissue function and development. [Display omitted] [ABSTRACT FROM AUTHOR]

A fast and safe dynamic process is a key issue during the start-stop and adjustment of high temperature proton exchange membrane electrolyzer cells (HT-PEMECs). In the paper, a 2D multi-physics model is developed to investigate the dynamic process in an HT-PEMEC. First, the dynamic responses of step scheme, multistep scheme and diagonal scheme are compared. It is found that the step scheme has the fastest dynamic response, but it may cause the problem of reactant starvation. The dynamic response speed of diagonal scheme is slower than the step scheme, but it can prevent the problem of reactant starvation. Subsequently, the dynamic process is optimized with a fast dynamic response without reactant starvation. This paper proposes a fast and safe dynamic process adjustment scheme and forms a basis for subsequent control of the HT-PEMEC stack and system. • 2D dynamic model for high temperature proton exchange membrane electrolyzer cells. • Transient response of different switching schemes are discussed. • Thermal safety and reactant starvation are considered. • The dynamic response process is optimized. [ABSTRACT FROM AUTHOR]

Exosomes are considered as biomarkers reflecting the physiological state of the human body. Studies have revealed that the expression levels of specific exosomal RNAs are closely associated with certain cancers. Thus, detection of exosomal RNA offers a new avenue for liquid biopsy of cancers. Many exosomal RNA detection methods based on various principles have been developed, and most of the methods detect the extracted RNAs after lysing exosomes. Besides complex and time-consuming extraction steps, a major drawback of this approach is the degradation of the extracted RNAs in the absence of plasma membrane and cytosol. In addition, there is considerable loss of RNAs during their extraction. In situ detection of exosomal RNAs can avoid these drawbacks, thus allowing higher diagnostic reliability. In this paper, in situ detection of exosomal RNAs was systematically reviewed from the perspectives of detection methods, transport methods of the probe systems, probe structures, signal amplification strategies, and involved functional materials. Furthermore, the limitations and possible improvements of the current in situ detection methods for exosomal RNAs towards the clinical diagnostic application are discussed. This review aims to provide a valuable reference for the development of in situ exosomal RNA detection strategies for non-invasive diagnosis of cancers. Certain RNAs have been identified as valuable biomarkers for some cancers, and sensitive detection of cancer-related RNAs is expected to achieve better diagnostic efficacy. Currently, the detection of exosomal RNAs is receiving increasing attention due to their high stability and significant concentration differences between patients and healthy individuals. In situ detection of exosomal RNAs has greater diagnostic reliability due to the avoidance of RNA degradation and loss. However, this mode is still limited by some factors such as detection methods, transport methods of the probe systems, probe structures, signal amplification strategies, etc. This review focuses on the progress of in situ detection of exosomal RNAs and aims to promote the development of this field. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper presents an experimental study about the proton exchange membrane fuel cell (PEMFC) behavior on linearly increasing loads. The study mainly based on the effect of the linear load slope on hydrogen consumption for 0–600 W range and 0–100 Watt/s slope. Experimental results are processed by Artificial Neural Networks (ANN) and Multiple Linear Regression (MLR). The relationship between total consumed energy, peak power, slope and hydrogen consumption are discussed and novel equations are presented. The average error rates of ANN and MLR are 0.3189%, and 0.1124% while the average R2 values are 0.9965 for ANN simulation and 0.9545 MLR simulation. We presented that the energy and exergy efficiency are decreased 6%, cost of the energy is increased 13% with the increasing slope of the power. We also performed the sensitivity and uncertainty analysis. The results give information to hydrogen system designers about an effective way to reach hydrogen consumption by performing both of the modelling processes successfully. • The paper discusses the hydrogen consumption calculation of proton exchange membrane fuel cell for linearly increasing loads. • Artificial neural networks and multiple linear regression are used for modelling the hydrogen consumption. • A new formula is proposed for hydrogen consumption calculation. • Energy, exergy, cost, sensitivity and uncertainty analysis are presented for different power slopes. [ABSTRACT FROM AUTHOR]

Nucleolin or C23, is one of the most abundant non-ribosomal phosphoproteins of nucleolus. However, in several cancers, nucleolin is highly expressed both intracellularly and on the cell surface. So, it is considered as a potential target for the diagnosis and cancer therapy. Targeting nucleolin by compounds such as AS1411 aptamer can reduce tumor cell growth. In this regard, interest has increased in nucleolin as a molecular target for overcoming cancer therapy challenges. This review paper addressed recent progresses in nucleolin targeting by the G-rich AS1411 aptamer in the field of cancer therapy mainly over the past three years. • Nucleolin is highly expressed both intracellularly and on the cell surface. • It is considered as a potential target for the cancer diagnosis and therapy. • AS1411 a 26-mer DNA aptamer that binds nucleolin. • This review paper addressed recent progresses in nucleolin targeting by the AS1411. [ABSTRACT FROM AUTHOR]

In this paper, a novel syngas-fed combined cogeneration plant, integrating a biomass gasifier, a molten carbonate fuel cell (MCFC), a heat recovery steam generator (HRSG) unit, a Stirling engine, and an organic Rankine cycle (ORC), is introduced and thermodynamically analyzed to recognize its potentials compared to the previous solo/combined systems. For the proposed system, energetic, exergetic as well as environmental evaluations are performed. Based on the results, the gasifier and the fuel cell have a significant contribution to the exergy destruction of the system. Through a parametric study, the current density and the stack temperature difference are known as the main effective factors on the plant performance. Meanwhile, dividing the whole system into three sub-models, i.e., model (1): power production plant including the gasifier and MCFC without including Stirling engine, HRSG, and ORC unit, model (2): the cogeneration system without ORC unit, and model (3): the whole cogeneration system, an environmental impact assessment is carried out regarding CO 2 emission. Considering paper as biomass revealed that maximum value of exergy efficiency is 50.18% with CO 2 emissions of 28.9 × 10−2 t.MWh−1 which compared to the solo MCFC system indicates 28.40% increase and 13.3 × 10−2 t.MWh−1 decrease in exergy efficiency and CO 2 emission, respectively. Image 1 • The 3E analyses of a CHP plant based on biomass gasifier and MCFC are performed. • The waste heat of the biomass-fueled MCFC system is recovered by HRSG, Stirling engine, and ORC. • The system yields an exergy efficiency of 50.18% with a CO 2 emission of 0.289 t/MWh. • The gasifier and fuel cell have the highest rates of exergy destruction. [ABSTRACT FROM AUTHOR]

TRPP2 (PC2, PKD2 or Polycytin-2), encoded by PKD2 gene, belongs to the nonselective cation channel TRP family. Recently, the three-dimensional structure of TRPP2 was constructed. TRPP2 mainly functions in three subcellular compartments: endoplasmic reticulum, plasma membrane and primary cilia. TRPP2 can act as a calcium-activated intracellular calcium release channel on the endoplasmic reticulum. TRPP2 also interacts with other Ca2+ release channels to regulate calcium release, like IP3R and RyR2. TRPP2 acts as an ion channel regulated by epidermal growth factor through activation of downstream factors in the plasma membrane. TRPP2 binding to TRPC1 in the plasma membrane or endoplasmic reticulum is associated with mechanosensitivity. In cilium, TRPP2 was found to combine with PKD1 and TRPV4 to form a complex related to mechanosensitivity. Because TRPP2 is involved in regulating intracellular ion concentration, TRPP2 mutations often lead to autosomal dominant polycystic kidney disease, which may also be associated with cardiovascular disease. In this paper, we review the molecular structure of TRPP2, the subcellular localization of TRPP2, the related functions and mechanisms of TRPP2 at different sites, and the diseases related to TRPP2. • The Structure of TRPP2: the voltage-sensing domain, the pore structural domain, and the TOP domain. • The main subcellular localization and function of TRPP2 in the endoplasmic reticulum, plasma membrane and cilia. • Mutations in TRPP2 have been reported to be associated with a variety of diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microporous Ti surface with aligned pores was synthesized successfully by electrochemical method. • Microporous Ti with aligned pore structure was controlled by electrochemical currents. • Microporous Ti promoted cell attachment and preferential growth on the aligned pores. This paper reports the synthesis of microporous Ti surfaces with aligned pores by applying a different current during electrochemical process for application in cell-surface interaction study and biomedical implants. As the microporous Ti surfaces were synthesized by current from (0.5–4)A, the microstructure of the Ti surfaces was shifted from a relative smooth to microporous one that was observed to have an aligned pore surface. Optical images showed that the micropore sizes in ∼(85.4–224.4)µm. The roughness of the microporous Ti was significantly higher than that of the Ti by a factor of approximately 5 to 7. Confocal laser scanning microscope showed excellent cell attachment and preferential growth on the microporous Ti with aligned channels after 72 h of culturing which could be important for cell-surface interactions study and biomedical implants. [ABSTRACT FROM AUTHOR]

[Display omitted] With the rapid increase in multidrug-resistance against antibiotics, higher doses of antibiotics or more effective antibiotics are needed to treat diseases, which ultimately leads to a decrease in the body's immunity and seriously threatens human health worldwide. The efficiency of antibiotics has been a large challenge for years. To overcome this problem, many carriers are utilized for anti-bacteria, attempting to optimize the delivery of such drugs and transport them safely and directly to the site of disease. Blood cell-based drug delivery systems present several advantages as compared to polymeric delivery system. These blood cells including red blood cells (RBCs), leukocytes, platelets. The blood cells and their membranes can both be used as drug carriers to deliver antibacterial drugs. In addition, blood cells can overcome many physiological/pathological obstacles faced by nanoparticles in vivo and effectively deliver drugs to the site of the disease. In this paper, we review studies on blood cell-based delivery systems used in antibacterial therapy, and analyze different roles in antibacterial therapy, which provide basis for further study in this field. [ABSTRACT FROM AUTHOR]

In our work, low potential and sensitive electrochemiluminescence (ECL) detection for CA153 on MCF-7 cell surface was firstly achieved based on a microfluidic paper-based analytical device. Au nanoflowers were grown in paper working electrode (PWE) to construct the ECL platform for primary antibodies immobilizing. After MCF-7 cells were captured in the modified PWE, and subsequently recognized with ECL signal substance labeled secondary antibodies, the sandwich-type cell sensor was fabricated. Graphene quantum dots (GQDs) loaded surface villous Au nanocages were synthesized as the ECL signal substance, and characterized by scanning electron microscope. The specific villous surface structure for Au nanocage permitted more GQDs being carried and electrons transporting, which largely benefited for the ECL performance. As the un-negligible impendence for MCF-7 cell would definitely influence the ECL signal, CA153 labeled HMEpic cell was used as the control cell to obtain more accurate determination result. This low-cost and fast strategy showed acceptable biocompatibility and stability, and will be promising for cellular immunochemistry. [ABSTRACT FROM AUTHOR]

Abstract Background Myriads of signaling pathways in a single cell function to achieve the highest spatio-temporal integration. Data are accumulating on the role of electromechanical soliton-like waves in signal transduction processes. Theoretical studies strongly suggest feasibility of both classical and quantum computing involving microtubules. Aim A theoretical study of the role of the complex composed of the plasma membrane and the microtubule-based cytoskeleton as a system that transmits, stores and processes information. Methods Theoretical analysis presented here refers to (i) the Penrose–Hameroff theory of consciousness (Orchestrated Objective Reduction; Orch OR), (ii) the description of the centrosome as a reference system for construction of the 3D map of the cell proposed by Regolini, (iii) the Heimburg–Jackson model of the nerve pulse propagation along axons' lipid bilayer as soliton-like electro-mechanical waves. Results and conclusion The ideas presented in this paper provide a qualitative model for the decision-making processes in a living cell undergoing a differentiation process. Outlook This paper paves the way for the real-time live-cell observation of information processing by microtubule-based cytoskeleton and cell fate decision making. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multidrug/multixenobiotic resistance (MDR/MXR) involves plasma membrane ABC and MFS efflux pumps. • Engineering of these transporters is a promising strategy for the development of superior yeasts. • Transcriptional regulation prediction provides clues for MDR/MXR efflux pumps expression engineering. • Understanding their physiological role is instrumental for increasing yeast robustness and bioproduct titers. Among the mechanisms used by yeasts to overcome the deleterious effects of chemical and other environmental stresses is the activity of plasma membrane efflux pumps involved in multidrug resistance (MDR), a role on the focus of intensive research for years in pathogenic yeasts. More recently, these active transporters belonging to the MFS (Drug: H+ antiporters) or the ABC superfamily have been involved in resistance to xenobiotic compounds and in the transport of substrates with a clear physiological role. This review paper focuses on these putative efflux pumps concerning their tolerance phenotypes towards bioprocess-specific multiple stress factors, expression levels, physiological roles, and mechanisms by which they may lead to multistress resistance. Their association with the increased secretion of metabolites and other bioproducts and in the development of more robust superior strains for Yeast Chemical Biotechnology is highlighted. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) cause more than 100,000 deaths each year, which need efficient and non-resistant antibacterial agents. SAR analysis of 162 flavonoids from the plant in this paper suggested that lipophilic group at C-3 was crucial, and then 63 novel flavonoid derivatives were designed and total synthesized. Among them, the most promising K15 displayed potent bactericidal activity against clinically isolated MRSA and VRE (MICs = 0.25–1.00 μg/mL) with low toxicity and high membrane selectivity. Moreover, mechanism insights revealed that K15 avoided resistance by disrupting biofilm and targeting the membrane, while vancomycin caused 256 times resistance against MRSA, and ampicillin caused 16 times resistance against VRE by the same 20 generations inducing. K15 eliminated residual bacteria in mice skin MRSA-infected model (>99 %) and abdominal VRE-infected model (>92 %), which was superior to vancomycin and ampicillin. [Display omitted] • Guided synthesis of flavonoid derivatives from 162 natural flavonoids. • Amphiphilic flavonoid derivatives displayed broad-spectrum antibacterial activity. • K15 avoided resistance by damaging biofilm and targeting cell membranes. • K15 exhibited excellent therapeutic effect in vivo , superior to vancomycin and ampicillin. [ABSTRACT FROM AUTHOR]

We describe in this paper the morphology of the male reproductive system, the spermiogenesis and the sperm ultrastructure of the drugstore beetle S. paniceum (L) (Coleoptera, Ptinidae). The male reproductive apparatus has a pair of long testes with six follicles, filled with cysts, each containing 128 germ cells. The sperm is about 480 μm long and is endowed of an apical spiral cylindrical acrosome, 1.7 μm long. The nucleus, 25 μm long, is also cylindrical at maturity. During spermiogenesis the nuclear envelope gives rise to two ovoid membranous structures flanking the nucleus for its whole length. The centriole adjunct material is configurated as concentric electron-dense rings. The flagellar components have a helical array; the axoneme has the typical 9 + 9+2 pattern for most of its length, but in the posterior flagellar region it modifies greatly its ultrastructure and is embedded in an electron-dense material. The two accessory bodies have a crescent-moon shape in the mature sperm, but at the beginning of spermiogenesis they are small structures lateral to the axoneme, later assuming a crescent-moon structure. A flattened cistern located between the axoneme and the plasma membrane is present in the early spermatids, but soon it fuses with the plasma membrane. Two symmetrical, largely crystallized mitochondrial derivatives are present for most of the flagellar length. S. paniceum and Lasioderma serricorne share several sperm structures. Ultrastructural results and molecular data confirm a close relationship between these two species and support their positioning within Ptinidae. • Males of Stegobium paniceum have long testes with six follicles each; • During spermiogenesis the nuclear envelope forms cytoplasmic ovoidal structures; • The spermatid shows a cistern further fusing with the dorsal plasma membrane: • The sperm posterior region has a modified and immotile flagellar axoneme. [ABSTRACT FROM AUTHOR]

A new design of multi-cell devices was proposed in this paper, and evaluated in terms of crashworthiness capability under quasi-static axial and oblique (9°, 18° and 27°) loading. The structures studied in the present paper were single and multi-cell members made up of two straight columns with the same shape of cross-section connected together by several ribs. They included several sectional configurations such as triangle, square, hexagon and circle with different scales (i.e. 0, 0.25, 0.5, 0.75 and 1). Finite element code LS-DYNA was used to simulate the crashworthiness behavior of the proposed members under quasi-static loads. Several crashworthiness indicators including SEA, F max and CFE were obtained at different crushing angles for all the columns, and a powerful decision making method known as COPRAS was then implemented to choose the best energy absorber with the criteria of having higher specific energy absorption and lower initial peak force. From the COPRAS calculations, the multi-cell members with inner tube and scale number of 0.5 were selected as the better energy absorbers, and the column with circular cross-section was also found to be the best energy absorbing device. [ABSTRACT FROM AUTHOR]

In a sequel of papers we have investigated effects of different physical contributions to the water holding capacity of foods by considering the common white button mushroom ( Agaricus bisporus ). In the current paper of our sequel, we consider individual contributions of the cellular phase to water holding. The water holding capacity of hydrated mushroom is studied in relation to cell membrane integrity loss and change of state of structural polymers of the cell wall. We show that the loss in water holding capacity after heat treatment is closely correlated with cell membrane integrity loss. The intrinsic water holding capacity of the cell wall components, mostly chitin and proteins also play a role. The contribution of protein manifests largely via a significant response of WHC towards change in pH. [ABSTRACT FROM AUTHOR]

The development of an effective delivery system for peptides targeting the tumor microenvironment has always been a hot topic of research in the field of cancer diagnosis and therapy. In this study, superparamagnetic iron oxide nanoparticles (SPIO NPs) were encapsulated with H460 lung cancer cell membranes (SPIO NP@M), and two peptides, namely PD-L1 inhibitory peptide (TPP1) and MMP2 substrate peptide (PLGLLG), were conjugated to the H460 membrane (SPIO NP@M-P). Homologous targeting, cytotoxicity, and pharmacokinetics of SPIO NP@M-P were evaluated. The TPP1 peptide was delivered and released to the tumor microenvironment through the homotypic effect of tumor cell membrane and specific digestion by the tumor-specific enzyme MMP2. The newly developed delivery system (SPIO NP@M-P) for the PD-L1 inhibitory peptide could effectively extend the half-life of the peptides (60 times longer than that for peptides alone) and could maintain the ability to reactivate T cells and inhibit the tumor growth both in vitro and in vivo. Furthermore, SPIO NPs in the system could be used as a tumor imaging agent and thus show the effect of peptide treatment. The SPIO NP@M might serve as a promising theranostic platform for therapeutic application of peptides in cancer therapy. A multifunctional delivery system (SPIO NP@M) was constructed for effectively delivering therapeutic peptides into the tumor microenvironment for cancer diagnosis and therapy. In this paper, the TPP-1 peptide inhibiting the binding of PD-L1 and PD-1 was delivered and released into the tumor microenvironment by the homotypic targeting of H460 cell membrane and specific digestion by the MMP2 enzyme. SPIO NPs in this system were aggregated effectively at the tumor sites and were used for magnetic resonance imaging of tumors. The SPIO NP@M-P delivery system could effectively extend the half-life of the TPP-1 peptide (60 times longer than that of the free peptide) and could maintain the ability to re-activate T cells and inhibit tumor growth in vitro and in vivo. In conclusion, the SPIO NP@M system coated with lung cancer cell membrane and loaded with the PD-L1-blocking TPP-1 peptide could be a promising integrated platform for tumor diagnosis and treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

The operating and designing parameters have significant influences on the performance of an air-cooled proton exchange membrane fuel cell. Figuring out the parameter sensitivity helps select the appropriate operating point and the geometry size for a fuel cell. In this paper, parameter sensitivity analysis is conducted for the performance and the internal transport phenomena of an air-cooled proton exchange membrane fuel cell based on different air stoichiometries, air relative humidities and air flow field designs. The numerical results show that large air stoichiometry helps lower the single cell temperature, keeps the membrane better hydrated, and improves cell performance. Especially, the fluctuation of water content always exists periodically for the case of different air stoichiometry, where the minimum value of water content appears underneath the cathode channel in contrast to the maximum value appearing underneath the cathode rib. Furthermore, the maximum periodic fluctuation amplitude of water content is even more than 8 for the case of air stoichiometry of 150. The water flooding phenomenon becomes severe with the increase of air stoichiometry. Air with larger relative humidity also increases the single cell performance by improving the hydration of the membrane. However, water flooding becomes worse with the increment of air relative humidity. The narrower channel design for the cathode flow field not only leads to a more uniform current density distribution but also keeps the membrane better hydrated and thus enhances the cell performance. • A full map of the internal transport phenomena of an AC PEMFC is presented. • The water content always oscillated periodically in the hydrogen flow direction. • Liquid water is easier to appear at larger air stoichiometry. • Single cell with narrower channel shows more uniform current and water content. • Lowering the temperature is a key point in the design of an AC PEMFC. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell (PEMFC) as a promising green power source, can be applied to vehicles, ships, and buildings. However, the lifetime of the fuel cell needs to be prolonged in order to achieve a wide range of applications. Consequently, the prediction of the health state draws attention lately and is critical to improving the reliability of the fuel cell. Since the degradation mechanism of the fuel cell is not fully understood, the data-driven method is very suitable for designing degradation prediction models. However, the data-driven method usually requires a lot of data, which is difficult to be obtained. To solve the issues, we propose a degradation prediction model for PEMFC based on long short-term memory neural network (LSTM) and Savitzky-Golay filter in this paper. First, we select the monitoring parameters for building the degradation prediction model by analyzing the degradation phenomenon of the fuel cell. Then, Savitzky-Golay filter is utilized to smooth out the selected data, and the sliding time window is used to generate training samples. Finally, the LSTM is applied to establish the degradation prediction model. Moreover, the dropout layer and mini-batch method are adopted to improve the model generalization ability. We use an actual aging data of the fuel cell to verified the proposed degradation prediction model. The results demonstrate that the proposed model can precisely predict the fuel cell degradation. It is worth mentioning that the determination coefficient (R2) of the test set based on the model trained by 25% of data is 0.9065. • The dimensions of the raw data are reduced by analyzing the degradation process of PEMFC. • Long short-term memory neural network is applied for degradation prediction. • The proposed model can precisely predict the degradation even when using less data. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cells (PEMFCs) employ a proton conductive membrane as the separator to transport a hydrogen proton from the anode to the cathode. The membrane's proton conductivity depends on the water content in the membrane, which is affected by the operating conditions. A membrane electrode assembly (MEA) that can self-sustain water is the key component for developing a light-weight and compact PEMFC system without humidifiers. Hence, zeolite is employed to the anode catalyst layer in this study. The effect of the gas diffusion layer (GDL) materials, catalyst loading, binder loading, and zeolite loading on the MEA performance is investigated. The MEA durability is also investigated through the electrochemical impedance spectroscopy (EIS) method. The results suggest that the MEA with the SGL28BCE carbon paper, Pt loadings of 0.1 and 0.7 mg cm−2 in the anode and cathode, respectively, Nafion-to-carbon weight ratio of 0.5, and zeolite-to-carbon weight ratio of 0.3 showed the best performance when the cell temperature is 60 °C and supplies with dry hydrogen and air from the environment. According to the impedance variation measured by EIS, the MEA with zeolite in the anode catalyst layer shows higher and more stable performance than those without zeolite. [Display omitted] • Optimum catalyst composition for dry hydrogen operation is obtained. • Pt loadings are 0.1 and 0.7 mg cm−2 for the anode and cathode, respectively. • Nation-to-carbon ratio of 0.5 presents best cell performance. • Zeolite-to-carbon ratio of 0.3 in the anode presents stable cell performance. • Mass transport Impedance of the cell with zeolite is reduced. [ABSTRACT FROM AUTHOR]

Pancreatic β-cells are equipped with the molecular machinery allowing them to respond to high glucose levels in the form of electrical activity and Ca2+ oscillations. These oscillations drive insulin secretion. Two key ionic mechanisms involved in this response are the Store-Operated Current and the current through ATP-dependent K+ channels. Both currents have been shown to be regulated by the protein STIM1, but this dual regulation by STIM1 has not been studied before. In this paper, we use mathematical modelling to gain insight into the role of STIM1 in the β-cell response. We extended a previous β-cell model to include the dynamics of STIM1 and described the dependence of the ATP-dependent K+ current on STIM1. Our simulations suggest that the total concentration of STIM1 modifies the bursting frequency, the burst duration and the intracellular Ca2+ levels. These results are in good agreement with experimental reports, and the contribution of the studied currents to electrical activity and Ca2+ dynamics is discussed. The model predicts that in the absence of STIM1 the excitability of the plasma membrane increases and that the glucose threshold for electrical activity is shifted to lower concentrations. These computational predictions may be related to impaired insulin secretion under conditions of reduced STIM1 in the diabetic state. [ABSTRACT FROM AUTHOR]

We outline the interaction of two-dimensional nanomaterial and cell barriers and their potential applications in major diseases. This paper aims to provide insights into the subsequent development of new smart nanomaterials capable of transport within cells. [Display omitted] The cell membrane serves as a barrier against the free entry of foreign substances into the cell. Limited by factors such as solubility and targeting, it is difficult for some drugs to pass through the cell membrane barrier and exert the expected therapeutic effect. Two-dimensional nanomaterial (2D NM) has the advantages of high drug loading capacity, flexible modification, and multimodal combination therapy, making them a novel drug delivery vehicle for drug membrane attachment and intracellular transport. By modulating the surface properties of nanocarriers, it is capable of carrying drugs to break through the cell membrane barrier and achieve precise treatment. In this review, we review the classification of various common 2D NMs, the primary parameters affecting their adhesion to cell membranes, and the uptake mechanisms of intracellular transport. Furthermore, we discuss the therapeutic potential of 2D NMs for several major disorders. We anticipate this review will deepen researchers' understanding of the interaction of 2D NM drug carriers with cell membrane barriers, and provide insights for the subsequent development of novel intelligent nanomaterials capable of intracellular transport. [ABSTRACT FROM AUTHOR]

Understanding the interaction of 2D materials including graphene, boron nitride and MoS 2 with biological systems is a growing topic of interest to many applications such as biosensors, drug delivery, gene therapy and nano-toxicity. In this paper, we show that the interaction of 2D materials with cellular membranes at its early stage of approaching is dominantly controlled by entropic forces. Recent experiments indicate that graphene sheets, depending on their size, can either undergo a near-orthogonal cutting or a parallel attachment mode of interaction with cell membranes. Here, we perform a set of integrated theoretical statistical mechanics analysis and coarse-grained molecular dynamics simulations to quantify the entropic energy barrier for these modes of interactions. Our results indicate that micro-sized graphene sheets prefer approaching a fluctuating membrane through a sharp corner, while nano-sized sheets are more likely to adhere to the cell membrane surface due to relatively low entropic energy cost that is comparable with thermal energy from random Brownian motions. • The interaction of 2D nanomaterials with biological systems is studied in this paper. • This interaction is dominantly controlled by entropic forces. • The entropic forces and energetic costs are calculated for two modes of interactions. • We show that micro-sized sheets always approach a cell membrane in perpendicular mode. [ABSTRACT FROM AUTHOR]

• We first described the S.maltophilia immunosuppressive effect on T cells and it is meaningful for immunosuppressed patients or co-infections. • T cells stimulated by S.maltophilia with CD4 and CD8 degraded via PD-1/PD-L1 pathway, which led to the massive apoptosis of T cells. • T cells were stimulated by S. maltophilia to secrete IFN-γ. Blocking the PD-1/PD-L1 pathway, apoptosis was suppressed. • S.maltophilia down-regulates host immunity by inhibiting immune cells. Smalotrophomonas maltophilia (S. maltophilia) is common in nosocomial infections. However, few studies have revealed the effect of S. maltophilia on cellular immunity in the host's immune system up to now. In clinical work, we accidentally discovered that S. maltophilia directly stimulated T cells to secrete IFN-γ. S. maltophilia was co-cultured with PBMCs to detect secretion of cytokines (IFN-γ, TNF-α and IL-2) and expression of cell surface molecules (CD3, CD4, CD8, CD69, CD147 and CD152) of T cells. We used light microscopy and electron microscopy to observe the cell morphology and subcellular structure of S. maltophilia co-cultured with lymphocytes. Flow cytometry and Western Blot were used to detect the expression of PD-1/PD-L1 and annexin V in cells. T cells stimulated by S. maltophilia secreted a large amount of IL-2, IFN-γ, and TNF-α. The expression of CD4 and CD8 on the cell surface were declined, accompanied by the activation of the PD-1/PD-L1 pathway, which eventually led to the massive apoptosis of T cells. Electron microscopy showed that cells showed significant apoptotic morphology. Blocking the PD-1/PD-L1 pathway can inhibit the apoptosis-inducing effect of S. maltophilia on T cells. These indicates that T cells are inhibited after being stimulated by S. maltophilia , and then accelerated to induce death without the initiation of an immunologic cascade. This paper demonstrates for the first time the inhibitory effect of S. maltophilia on cellular immunity, and the immunosuppressive effect induced by infection of S. maltophilia should be considered. [ABSTRACT FROM AUTHOR]

• MR1, a non-polymorphic ubiquitous antigen presenting molecule presents small metabolites to T cells. • MR1T cells recognize small drugs and microbial metabolites presented by MR1. • MR1T cells also recognize self-metabolites accumulating in tumor cells. • MR1T cells are multi-functional and express polyclonal TCR heterodimers. MR1 is an MHC class I-like molecule with unique structural and biological features that make it an important member among the molecules involved in antigen presentation to T cells. Distinctive features include ubiquitous expression of the MR1 gene and its monomorphism. Another relevant property is that the MR1 protein appears at very low levels on the plasma membrane and its surface expression is regulated by antigen binding. Finally, the nature of presented antigens differs from those that bind other presenting molecules and includes small metabolites of microbial and self-origin, small drugs and tumor-associated antigens. This opinion paper describes in detail some of those features and discusses recent literature in the field. [ABSTRACT FROM AUTHOR]

The biocompatibility of silicon nitride ceramics was proven by several studies however this study is apart from the literature in the manner of production routes that are tape casting and partial sintering. We report the tape casting route was chosen and a porous structure was obtained by partial sintering technique. Tape casting brought a smooth surface to the samples. Density and pore size distribution analysis showed that the scaffolds have low density because of the porous structure. XRD and SEM analyses were carried out to reveal the phase and microstructural characteristics of porous ceramic samples. Static contact angle measurement was done for the characterization of the wettability of the scaffolds. It revealed that the surface of the scaffolds was highly hydrophilic which is a desirable characteristic for the protein and cell adhesion. The mechanical characteristics of the scaffolds were analyzed by compression tests. Human osteosarcoma cells were used for in vitro studies. Cell-proliferation and cytotoxicity were analyzed by WST-1 and LDH, respectively. The osteoblastic behavior of the cells on the surface of the scaffolds was identified by alkaline phosphatase activity. BCA analysis was used for total protein content. The BCA and ALP results showed an increasing trend which is directly correlated with cell proliferation. Cells on the surface of the silicon nitride scaffolds were visualized by SEM and fluorescence microscopy where the images supported the in vitro analysis. Therefore, porous silicon nitride scaffolds fabricated via tape casting and partial sintering were biocompatible and they are possible candidates as bone substitute elements. Image 1 [ABSTRACT FROM AUTHOR]

Flow field (FF) directly influences many functions of proton-exchange membrane fuel cell (PEMFC), namely, the even distribution and isolation of reaction gas, and electrical connection between cells. However, the influence depends heavily on FF structure and external factors. This paper explores the effects of gas diffusion layer (GDL) porosity, inlet speed, temperature, length, width, and depth on the performance of PEMFC with serpentine FF (SFF) through mathematical modelling and statistical analysis, with the aim to disclose the change law of cell performance under the combined effects of structural parameters and those of external factors. The combination of structural parameters and external factors were optimized, and proved valid by the electrochemical performance of SFF PEMFC. The results show that 8-channel complex SFF is the best channel pattern; the optimal width-depth combination is 1.2 mm wide and 0.8 mm deep; GDL porosity is the primary factor affecting water distribution, current density distribution and oxygen distribution of SFF PEMFC compare with the aspects of inlet speed and temperature. The research results provide a good reference for optimizing the FF for better PEMFC performance. [ABSTRACT FROM AUTHOR]

SFAs play the leading role in 1 of the greatest controversies in nutrition science. Relative to PUFAs, SFAs generally increase circulating concentrations of LDL cholesterol, a risk factor for atherosclerotic cardiovascular disease (ASCVD). However, the purpose of regulatory mechanisms that control the diet-induced lipoprotein cholesterol dynamics is rarely discussed in the context of human adaptive biology. We argue that better mechanistic explanations can help resolve lingering controversies, with the potential to redefine aspects of research, clinical practice, dietary advice, public health management, and food policy. In this paper we propose a novel model, the homeoviscous adaptation to dietary lipids (HADL) model, which explains changes in lipoprotein cholesterol as adaptive homeostatic adjustments that serve to maintain cell membrane fluidity and hence optimal cell function. Due to the highly variable intake of fatty acids in humans and other omnivore species, we propose that circulating lipoproteins serve as a buffer to enable the rapid redistribution of cholesterol molecules between specific cells and tissues that is necessary with changes in dietary fatty acid supply. Hence, circulating levels of LDL cholesterol may change for nonpathological reasons. Accordingly, an SFA-induced raise in LDL cholesterol in healthy individuals could represent a normal rather than a pathologic response. These regulatory mechanisms may become disrupted secondarily to pathogenic processes in association with insulin resistance and the presence of other ASCVD risk factors, as supported by evidence showing diverging lipoprotein responses in healthy individuals as opposed to those with metabolic disorders such as insulin resistance and obesity. Corresponding with the model, we suggest alternative contributing factors to the association between elevated LDL cholesterol concentrations and ASCVD, involving dietary factors beyond SFAs, such as an increased endotoxin load from diet–gut microbiome interactions and subsequent chronic low-grade inflammation that interferes with fine-tuned signaling pathways. [ABSTRACT FROM AUTHOR]

It is necessary to have an energy management system based on one or more control strategies to sense, monitor, and control the behavior of the hybrid energy sources. In renewable hybrid power systems containing fuel cells and batteries, the hydrogen consumption reduction and battery state of charge (SOC) utilizing are the main objectives. These parameters are essential to get the maximum befits of cost reduction as well as battery and hydrogen storage lifetime increasing. In this paper, a novel hybrid energy management system (HEMS) was designed to achieve these objectives. A renewable hybrid power system combines: PV, PEMFC, SC, and Battery was designed to supply a predetermined load with its needed power. This (REHPS) depends on the PV power as a master source during the daylight. It uses the FC to support as a secondary source in the night or shading time. The battery is helping the FC when the load power is high. The supercapacitor (SC) is working at the load transient or load fast change. The proposed energy management system uses fuzzy logic and frequency decoupling and state machine control strategies working together as a hybrid strategy where the switching over between both strategies done automatically based on predetermined values to obtain the minimum value of hydrogen consumption and the maximum value of SOC at the same time. The proposed HEMS achieves 19.6% Hydrogen consumption saving and 5.4% increase in SOC value compared to the results of the same two strategies when working as a stand-alone. The load is designed to show a surplus power when the PV power is at its maximum value. This surplus power is used to charge the battery. To validate the system, the results were compared with the results of each strategy if working separately. The comparison confirms the achievement of the hybrid energy management system goal. • Hybrid energy management system designed to minimize hydrogen consumption in FC. • Hybrid energy management system designed to optimize the battery state of charge. • A battery is helping the FC when the load power is high. • A supercapacitor (SC) is working at the load transient or load fast change. • The proposed management systems decreased hydrogen consumption by 20%. [ABSTRACT FROM AUTHOR]

This paper reports on a sizing procedure for integrated Anaerobic Reactor/Solid Oxide Fuel Cell cogeneration energy system powered by livestock waste, in order to meet the provisions of Industry 4.0, connected to the new paradigm of Agriculture 4.0. The algorithm accounts on two main computational blocks, associated to the biogas production plant and to the SOFC energy unit respectively. A numerical modeling is performed to dimension the anaerobic digester and the biogas production deriving, as well as to dimension the energy unit and determine its techno-energy performance when it is fed by the previous biogas. An application of the algorithm is made to a mid-size livestock farm, in order to valorize the biomass waste produced in situ. [ABSTRACT FROM AUTHOR]

Voltage support is one of the most important issues for operating grid-connected inverters under grid faults. Many control strategies have been addressed in literature, but most of them focus on the voltage support control without considering issues of power quality due to voltage harmonics. In order to sort out the drawback, a novel advanced control strategy is presented in this paper. It is able to provide the voltage support function. Meanwhile, the power quality is improved by regulating the control coefficients. The time-domain simulation and experimental results are provided to evaluate the conventional and proposed control strategies. The results show that the total harmonic distortion of PCC voltage can be reduced from 9.35% to 2.88% with the proposed solution. Meanwhile, the voltage support is also achieved, which verify the effectiveness of the proposed solution. • An control of inverter is proposed for proton exchange membrane fuel cell system. • Both the voltage support and power quality improvement can be achieved. • The THD of PCC voltage is reduced from 9.35% to 2.88% with the proposed solution. • Experimental investigation of the proposed solution is provided. [ABSTRACT FROM AUTHOR]

In this paper a novel strategy using type-3 (T3) fuzzy logic systems (FLSs) is designed for voltage management in the hybrid systems that include photovoltaic, battery and hydrogen fuel cells (FC). The stability and robustness are proved in the versus of time-variable irradiation, temperature and output load. The suggested T3-FLS is learned by tuning laws that are concluded form robustness analysis. The effects of perturbations and estimation errors are compensated by the schemed controller such that a good regulation performance to be achieved. The performance of the suggested technique is examined under challenging conditions such as time-variable and unknown dynamics, variable irradiation, variable temperature and abruptly changes in output load. Comparison with classic management methods show that the suggested approach results in better regulation performance, in the circumstances that, unlike to the compared methods, the mathematical dynamics of all units are assumed to be unknown. • A novel voltage management technique is presented on basis of T3-FLSs. • The effects of challenging conditions are compensated by the suggested algorithm. • The robustness and stability of the suggested algorithm is ensured. • The suggested method is adaptive and it is online optimized. [ABSTRACT FROM AUTHOR]

In this paper, the hydrogen and nitrogen crossover through the membrane in proton exchange membrane fuel cells, are investigated by developing a semi-empirical analytical model. Different factors that affect the gas crossover rates were considered including pressure drop in gas diffusion layer (GDL) and catalyst layer (CL), operating temperature, relative humidity (RH) of the reactants, GDL compression, and the current density effect on the membrane temperature. The model is validated by published experimental data. It is found that RH is the most important parameter, followed by temperature. The hydrogen pressure drop through GDL and CL greatly depends on the GDL substrate properties, microporous layer (MPL) and CL. When permeability is low, an increase in current density reduces gas crossover. GDL compression, when MPL is used, was found to have a low impact on gas crossover. Gas crossover is improved with current density due to an increase in membrane temperature. • Hydrogen crossover is PEM fuel cells is investigated. • Relative humidity is the most important parameter in gas crossover. • Operating temperature also plays an important role in gas crossover. • Membrane temperature increase with current density can increase the gas crossover. • Assembly pressure have small effect on hydrogen crossover. [ABSTRACT FROM AUTHOR]

The proton exchange membrane fuel cell has been widely used for industrial systems; however, its performance gradually degrades during use. Therefore, the study on the performance degradation prediction of fuel cells is helpful to extend its lifespan. In this paper, a novel hybrid approach using a combination of model-based adaptive Kalman filter and data-driven NARX neural network is proposed to predict the degradation of fuel cells. The overall degradation trend (i.e., irreversible degradation process) is captured by an empirical aging model and adaptive Kalman filter. Meanwhile, the detail degradation information (i.e., reversible degradation process) is depicted by the NARX neural network. Moreover, the correlation analysis of the reversible voltage time series is carried out to obtain the number of delays of the NARX neural network based on the autocorrelation function and the partial autocorrelation function. Then, the total degradation prediction is the sum of the overall degradation prediction and the detail degradation prediction. Finally, the prognostic capability of the proposed method is verified by two aging datasets, and the results show the effectiveness and superiority of the proposed method which can provide accurate degradation forecasting and remaining useful life. • Overall degradation trend of fuel cell is captured by an empirical aging model. • The adaptive extended Kalman filter is used to track the overall degradation trend. • The NARX neural network is used to predict the detail degradation information. • The correlation analysis is used to obtain the number of delays of NARX model. • The hybrid approach with different prediction horizon is verified by experiments. [ABSTRACT FROM AUTHOR]

Electrophysiologists routinely use simple voltage steps to evaluate cell membrane capacitance derived from corresponding current responses. Frequently, the resting membrane voltage V rest is employed as holding potential for the subsequent command voltage step and more or less accurate methods are utilised to analyse the transient current. Another choice as holding potential is the peak of the "quasi steady-state" current to voltage relationship, V peak. The aim of this study is the systematic evaluation of capacitance estimation accuracy from voltage step experiments depending on the choice of holding potential and analysis method. In this paper, a simulation approach is employed to analyse the current response of a model patch-clamp circuit. Four commonly accepted methods are implemented, utilizing different aspects of the transient current (charge, membrane time constant, and influence of the series resistance) in various combinations and with various degrees of refinement. This simulation study indicates an acceptable accuracy of the elaborated methods for capacitance estimation at holding potentials V rest and V peak over a broad range of capacitance as well as series resistance values. Simple integration of the current transient provides sufficient accuracy at holding potentials, which effectively minimizes changes in resistive membrane current flow during command voltage steps (particularly around V peak). However, biphasic command protocols performed at V peak activate voltage dependent sodium channels, thereby possibly leading to the threshold voltage for an action potential. Compared to V rest , all methods utilizing monophasic step protocols, gain additional accuracy, when applied at V peak as holding potential. [ABSTRACT FROM AUTHOR]

The durability of fuel cells is significantly impaired by chemical and mechanical degradations of perfluorosulfonic-acid membranes. However, how the mechanical degradation, especially the fatigue crack propagation behavior, is impacted by chemical degradation is not clear. In this paper, the fatigue crack propagation behavior of Nafion 212 and Nafion XL composite membranes after chemical degradation are investigated. The fluoride release rates of Nafion 212 and Nafion XL membrane are 0.335 and 0.095 μmol cm−2 h−1, respectively. Likewise, the fatigue crack propagation rate of Nafion 212 membrane is also larger, which is attributed to two fatigue crack propagation mechanisms induced by chemical degradation, including bubble collapsing and pore interconnecting. By contrast, the fatigue crack propagation mechanism of Nafion XL membrane is not significantly changed where chemical degradation only accelerates crack growth in exterior surface layers. These findings provide new insights into the failure mechanisms under combined chemical and mechanical degradations. Image 1 • Fatigue crack propagation behavior after chemical degradation are investigated. • Fluoride release and fatigue crack propagation rate of two membranes are compared. • Two new fatigue crack propagation mechanisms are identified for Nafion 212 membrane. • Chemical degradation does not change crack growth mechanism of Nafion XL membrane. • The role of reinforcement layer is more important with increasing degradation level. [ABSTRACT FROM AUTHOR]

The α-adrenergic agents are known to influence erection and ejaculation, and ejaculatory reflex is a primarily α-adrenergically mediated event. This paper aims to describe the urethral catheterization technique after pharmacological induction for semen collection in domestic dogs. For dose determination, semen collection was performed using increasing doses of dexmedetomidine (5 μg/kg, n = 2; 10 μg/kg, n = 2 and 15 μg/kg, n = 2) associated to 3 mg/kg ketamine in six animals. Once the dose was established, additional semen collection using association of 15 μg/kg dexmedetomidine and 3 mg/kg ketamine was carried out in eight dogs. After the procedure, sperm volume (0.092 ± 0.03 mL), total motility (58.33 ± 8.7%), vigor (1.89 ± 0.309), sperm concentration (1186.67 ± 304.667 × 106 sperm/mL), sperm plasma membrane integrity (83.22 ± 4.82%), acrosomal integrity (73 ± 6.187%) and normal sperm morphology (53.22 ± 5.6%) were assessed. Thus, this study demonstrates that urethral catheterization after pharmacological ejaculation using dexmedetomidine-ketamine association can be performed in dogs and it may be possible to obtain good semen quality, despite urine contamination. • Semen release and ejaculatory reflex are events mediated by α-adrenergic stimuli. • Administration of dexmedetomidine intramuscular leads to release of semen into the urethra in dogs. • Dexmedetomidine dose correlates with semen release effect. • The semen sample had low volume, high concentration, high viability, and low urine contamination. [ABSTRACT FROM AUTHOR]

The fuel cell reliability and durability are still the main factors limiting the large scale commercialization. To a certain degree, water content, transportation, distribution and state in the fuel cell influence the fuel cell State of Health (SOH). However, it's very difficult to measure water content inside fuel cell directly. The PEMFC system voltage fluctuate during hydrogen purging process, due to the removal of liquid water will affect the reactants transformation. Different internal water content will cause different voltage fluctuations. For this characteristic, The Energy Intensity of Reconstructed Vibrating Voltage (EIV) based on wavelet transformation is proposed and validated in this paper. The boundary value of EIV is determined to be 0.1 through experiments. The results show that the fuel cell voltage drop is reduced to 0.32 V/h from 1.39 V/h by using this method to avoid anode flooding. By several PEMFC system experiment results in test bench, this method can diagnosis the water content in PEMFC properly. • A PEMFC system voltage fluctuation model during hydrogen purge process is established. • A water content diagnosis algorithm is designed based on wavelet transformation. • The water content in PEMFC can be diagnosed properly without any other hardware. [ABSTRACT FROM AUTHOR]

Biomimetic nanotechnology through camouflaging synthetic nanoparticles (NPs) with natural cell membranes, which bestows with immune evasion and superior targeting capacity, has been extensively used in drug delivery systems (DDS) over the last decades. These biomimetic NPs not only retain the physicochemical features of the synthetic vehicles but also inherit the cell membranes' intrinsic functionalities. Combined with these benefits, optimized nano-biomimetic DDS allow maximum delivery efficacy. Compared to erythrocyte/cancer single cell membrane, the hybrid cell membrane expressing CD47 membrane protein and self-recognition molecules, from erythrocytes and cancer cells, provides remarkable features to the synthetic vehicles, such as immune evasion, long-term circulation, and homotypic targeting. In this review, we describe the preparation strategies, the camouflaging mechanism, and the antitumor applications of hybrid cell membrane-camouflaged NPs. Moreover, we discuss further modification of the hybrid cell membrane and the surface properties of fusion cellular membranes. Finally, we summarize the primary challenges and opportunities associated with these NPs. Camouflaging synthetic nanoparticles with hybrid cell membrane has been extensively highlighted in recent years. The resultant biomimetic nanoparticles not only reserve the physicochemical properties of the synthetic nanoparticles but also inherit the biological functions of source cells. Compared with single cell membrane, hybrid cell membrane can endow synthetic nanoparticles with multiple biofunctions derived from the original source cells. To provide a timely review of this rapidly developing subject of research, this paper summarized recent progress on the hybrid cell membrane-camouflaged nanoparticles as drug delivery systems for cancer diagnosis and treatment. In this review, we focused primarily on five different types of hybrid cell membrane-camouflaged nanoparticles with the preparation strategies, the camouflaging mechanism, and the antitumor applications. Moreover, further modification of the hybrid cell membrane was also discussed for isolating effectively circulating tumor cells. Image, graphical abstract [ABSTRACT FROM AUTHOR]

In spite of significant achievements in alkaline exchange membrane fuel cells (AEMFCs) in recent years, they are still lagging behind proton exchange membrane fuel cells (PEMFCs) due to performance instability. Among the relevant operational parameters of AEMFC, the researchers have found that poor water management within the cell was the main reason for failure of the system. In the past five years, numerous modeling and experimental works were reported proposing different strategies to improve water management of AEMFC. With proper water management, the achievable power output in AEMFCs is comparable with that of PEMFCs or even more. Efforts have to be continued, but AEMFCs can become a strong competitor in the market place. This review paper discusses the strategies and developments impacting water management of AEMFCs providing knowledge source for upcoming studies. • Water dynamics are more complex in AEMFC than PEMFC. • PTFE in GDL plays crucial role in water management. • Pt and ionomer loading in the electrode strongly impacts water management. • AEM with low diffusion resistance mitigates anode flooding. • Operating conditions (RH, T) should be optimized for stable AEMFC performance. [ABSTRACT FROM AUTHOR]

The machine vision based methods for micro-cracks detection of solar cells surface have become one of the main research directions with its efficiency and convenience. The existed methods are roughly classified into two categories: current viewing information based methods, prior knowledge based methods, however, the former usually adopt hand-designed features with poor generality and lacks the guidance of prior knowledge, the latter are usually implemented through the machine learning, and the generalization ability is also limited since the large-scale annotation dataset is scarce. To resolve above problems, a novel micro-cracks detection method via combining short-term and long-term deep features is proposed in this paper. The short-term deep features which represent the current viewing information are learned from the input image itself through stacked denoising auto encoder (SDAE), the long-term deep features which represent the prior knowledge are learned from a large number of natural scene images that people often see through convolutional neural networks (CNNs). The subjective and objective evaluations demonstrate that: 1) the performance of combining the short-term and long-term deep features is better than any of them alone, 2) the performance of proposed method is superior to the shallow learning based methods, 3) the proposed method can effectively detect various kinds of micro-cracks. [ABSTRACT FROM AUTHOR]