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In this work, a current and magnetic field sensor is proposed and experimentally demonstrated utilizing a fiber-optic Mach–Zehnder interferometer (MZI) structure. In our setup, one of the interferometer arms is coated with magnetic nanoparticles. The MZI comprises a laser source emitting an optical signal, split by a coupler into two signals propagated by a reference fiber and a sensor fiber. The sensing fiber is encased in cobalt ferrite (CoFe2O4). Upon exposure to a magnetic field, CoFe2O4 induces vibration in the fiber, modifying the sensor's transmission and causing an imbalance between the optical signals of the interferometer arms. This enables us to evaluate the sensor performance regarding sensitivity, accuracy, and saturation. The nanoparticles were synthesized using the protein sol–gel method, resulting in an average crystallite size of 8, 27, and 67 nm for 623, 773, and 1073 K, respectively. Sample characterizations were conducted through X-ray fluorescence, X-ray diffraction, VSM magnetic measurements, and Mössbauer spectroscopy for further analysis of the performance. The sensor exhibited a linear response, achieving a maximum regression between 93.0% and 98.6% across all sample points in the 0 to 150 Oe range, with an output power of approximately 20 dBm, correlated with the applied magnetic field. Sensitivity was measured at 1.15, 0.93, and 1.41 dB/Oe. Previous studies have correlated the horizontal width of the hysteresis loop with sensor saturation. However, by employing a different coating in this work, we complement these findings by demonstrating that the sensor does not saturate if the maximum applied field is smaller than the hysteresis loop width. [ABSTRACT FROM AUTHOR]

The industrial sector plays a significant role in global economic growth. However, it also produces polluting effluents that must be treated to prevent environmental damage and ensure the quality of life for future generations is not compromised. Various physical, chemical, and biological methods have been employed to treat industrial effluents. Filamentous fungi, in particular, have garnered attention as effective bioremediation agents due to their ability to produce enzymes capable of degrading recalcitrant compounds, and adsorb different pollutant molecules. The novelty of the work reported herein lies in its comprehensive assessment of the research surrounding the use of white- and brown-rot fungi for removing phenolic compounds from industrial effluents. This study employs a systematic review coupled with scientometric analysis to provide insights into the evolution of this technology over time. It scrutinizes geographical distribution, identifies research gaps and trends, and highlights the most studied fungal species and their applications. A systematic review of 464 publications from 1945 to 2023 assessed the use of these fungi in removing phenolic compounds from industrial effluents. White-rot fungi were predominant (96.3%), notably Phanerochaete chrysosporium, Pleurotus ostreatus, Trametes versicolor, and Lentinula edodes. The cultures employing free cells (64.15%) stand out over those using immobilized cells, just like cultures with isolated fungi regarding systems with microbial consortia. Geographically, Italy, Spain, Greece, India, and Brazil emerged as the most prominent countries in publications related to this area during the evaluated period. [ABSTRACT FROM AUTHOR]

Considering the high level of heat and flame exposure firefighters encounter while performing their work activities, personal protective equipment (PPE) is of the utmost importance to enhance their safety. Phase change materials (PCMs) are known as advanced materials able to absorb high amounts of thermal energy, with the potential to increase the thermal performance of protective clothing. In this work, a PCM-vest was developed for the first time, and its thermal performance was evaluated. A three-stage approach was followed: (1) at a small scale in the laboratory, the effect of different encapsulated PCMs on a multilayer assembly performance was evaluated; (2) in the laboratory, the essential requirements of heat and flame tests were assessed; and (3) in a simulated urban fire, the thermal performance of three different PCM-vests (different textiles and designs) was studied. As the main conclusions, the PCMs significantly affected the heating rate of the multilayer assembly, particularly when a PCM with higher latent heat was used. In some cases, the heat transfer index (HTI) doubled by comparison with the sample without PCMs. As a drawback and as expected, the cooling time was increased. The PCM-vest sample ensured the requirements of the heat and flame tests. Through this study, the positive impact of using PCMs to enhance the heat protection of conventional PPE can be highlighted. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) are becoming increasingly popular due to their low emissions, energy efficiency, and reduced reliance on fossil fuels. One of the most critical components in an EV is the energy storage and management system, which requires compactness, lightweight, high efficiency, and superior build quality. Active cell equalization circuits such as those used in battery management systems (BMS) have been developed to balance the voltage and state of charge (SoC) of individual cells, ensuring the safety and reliability of the energy storage system. The use of these types of equalization circuits offers several benefits including improved battery performance, extended battery life, and enhanced safety, which are essential for the successful adoption of EVs. This paper provides a comprehensive overview of the research works related to active cell equalization circuits. This review highlights the important aspects, advantages and disadvantages, and specifications. [ABSTRACT FROM AUTHOR]

The separation of red blood cells (RBCs) from blood plasma and the analysis of individual RBCs are of great importance, as they provide valuable information regarding the health of their donor. Recent developments in microfluidics and microfabrication have contributed to the fabrication of microsystems with complex features to promote the separation and analysis of RBCs. In this work, the separation capacity of a multi-step crossflow microfluidic device was evaluated by using a blood analogue fluid made by Brij L4 micelles and human RBCs separated from whole blood, suspended in a solution with hematocrits (Ht) of 0.5 and 1%. All the samples collected at the outlets of the device were experimentally analyzed and compared. The absorbance spectrum was also measured for the prepared blood samples. The results indicate that the tested blood analogue fluid has exhibited a flow behavior similar to that of blood. In addition, the optical absorbance spectrophotometry revealed that it was possible to evaluate the separation efficiency of the microfluidic device, concluding that the concentration of cells was lower at the most lateral outside outlets of the microchannel due to the cumulative effect of the multiple cross-flow filters. [ABSTRACT FROM AUTHOR]

Plant-derived (poly)phenolic compounds have been undoubtedly shown to promote endocrine homeostasis through the improvement of diverse metabolic outcomes. Amongst diverse potential mechanisms, the prebiotic modulatory effects exerted by these compounds on the gut microbiota have supported their nutraceutical application in both experimental and clinical approaches. However, the comprehension of the microbiota modulatory patterns observed upon (poly)phenol-based dietary interventions is still in its infancy, which makes the standardization of the metabolic outcomes in response to a given (poly)phenol a herculean task. Thus, this narrative review sought to gather up-to-date information on the relationship among (poly)phenols intake, their modulatory effect on the gut microbiota diversity, and consequent metabolic outcomes as a supportive tool for the future design of experimental approaches and even clinical trials. [ABSTRACT FROM AUTHOR]

The continuous research and development regarding firefighters' personal protective equipment (PPE) has led to significant improvements in recent decades. Despite the evolution of firefighters' PPE, every year an undesirable number of firefighters are seriously burned during firefighting operations, with some of them eventually losing their lives. The protection given by firefighters' PPE can be further increased with the incorporation of smart textiles in the personal protective equipment, namely, wearable electronics (i.e., integrated sensors to monitor diverse parameters: heart rate, oxygen saturation, carbon dioxide detector, and setting real-time communication with a command post) and advanced materials such as phase change materials (PCMs). The evolution of firefighters' PPE has been followed by an evolution and update in the international and national standards that specify performance requirements for firefighters' protective clothing for structural and wildland firefighting as well as technical rescue. This study will focus on the analysis of firefighters protective clothing evolution regarding the use and integration of advanced smart materials, namely, phase change materials, taking into consideration the evolution and requirements of international and European standards as well as national legislation for firefighters' protective clothing. [ABSTRACT FROM AUTHOR]

Simple Summary: Heat stress in cattle is broadly defined as a physiological condition in which body temperature rises, and the animals are no longer able to adequately dissipate body heat to maintain thermal equilibrium due to environmental factors. Dairy cattle are particularly sensitive to heat stress because of the higher metabolic rate needed for milk production. Due to global warming and the expected growth of milk production in warmer regions, an increase in the occurrence of heat stress can only be avoided with the use of environmental control systems. However, most available systems were developed to take corrective measures or are not accurate enough to effectively prevent heat stress, as there is not yet an automated technological solution that considers all the environmental and animal variables that determine the occurrence of this condition. Further, these systems must be connected in time to prevent this condition in cattle but also disconnected when they are no longer needed, as their use raises major economic and environmental concerns regarding energy and water consumption. This review describes and discusses three types of predictive models that can make these systems more effective in preventing heat stress and more efficient in the use of energy and water. Dairy cattle are particularly sensitive to heat stress due to the higher metabolic rate needed for milk production. In recent decades, global warming and the increase in dairy production in warmer countries have stimulated the development of a wide range of environmental control systems for dairy farms. Despite their proven effectiveness, the associated energy and water consumption can compromise the viability of dairy farms in many regions, due to the cost and scarcity of these resources. To make these systems more efficient, they should be activated in time to prevent thermal stress and switched off when that risk no longer exists, which must consider environmental variables as well as the variables of the animals themselves. Nowadays, there is a wide range of sensors and equipment that support farm routine procedures, and it is possible to measure several variables that, with the aid of algorithms based on predictive models, would allow anticipating animals' thermal states. This review summarizes three types of approaches as predictive models: bioclimatic indexes, machine learning, and mechanistic models. It also focuses on the application of the current knowledge as algorithms to be used in the management of diverse types of environmental control systems. [ABSTRACT FROM AUTHOR]

In recent years, the nanofluids (NFs) have become the main candidates for improving or even replacing traditional heat transfer fluids. The possibility of NFs to be used in various technological applications, from renewable energies to nanomedicine, has made NFs and their thermal conductivity one of the most studied topics nowadays. Hence, this review presents an overview of the most important advances and controversial results related to the NFs thermal conductivity. The different techniques used to measure the thermal conductivity of NFs are discussed. Moreover, the fundamental parameters that affect the NFs thermal conductivity are analyzed, and possible improvements are addressed, such as the increase of long-term stability of the nanoparticles (NPs).The most representative prediction classical models based on fluid mechanics, thermodynamics, and experimental fittings are presented. Also, the recent statistical machine learning-based prediction models are comprehensively addressed, and the comparison with the classical empirical ones is made, whenever possible. [ABSTRACT FROM AUTHOR]

In this study, a numerical approach was carried out to analyze the effects of different geometries of microchannel heat sinks on the forced convective heat transfer in single-phase flow. The simulations were performed using the commercially available software COMSOLMultiphysics 5.6® (Burlington, MA, USA) and its results were compared with those obtained from experimental tests performed in microchannel heat sinks of polydimethylsiloxane (PDMS). Distilled water was used as the working fluid under the laminar fluid flow regime, with a maximum Reynolds number of 293. Three sets of geometries were investigated: rectangular, triangular and circular. The different configurations were characterized based on the flow orientation, type of collector and number of parallel channels. The main results show that the rectangular shaped collector was the one that led to a greater uniformity in the distribution of the heat transfer in the microchannels. Similar results were also obtained for the circular shape. For the triangular geometry, however, a disturbance in the jet impingement was observed, leading to the least uniformity. The increase in the number of channels also enhanced the uniformity of the flow distribution and, consequently, improved the heat transfer performance, which must be considered to optimize new microchannel heat sink designs. The achieved optimized design for a heat sink, with microchannels for nanofluid flow and a higher heat dissipation rate, comprised a rectangular collector with eight microchannels and vertical placement of the inlet and outlet. [ABSTRACT FROM AUTHOR]

35208307 2 Zhao X., Guo Z., Zhou Y., Guo J., Liu Z., Li Y., Luo M., Wu X. Optical whispering-gallery-mode microbubble sensors. Liu et al. [[5]] developed a platform for sonoporation of cell membranes that uses ultrasounds combined with a microbubble attached to the cell membrane wall. 35457896 3 Chen X., Song Q., Zhang B., Gao Y., Lou K., Liu Y., Wen W. A rapid digital pcr system with a pressurized thermal cycler. [Extracted from the article]

A deep knowledge of the hydrodynamics of two-phase flow in millichannels and microchannels is relevant to the design and control of micro structured equipment. While there is plenty of work published in this area, there is a lack of studies over a wide range of dimensionless numbers and some factors have not been properly addressed, such as the role of the Reynolds number, the features of recirculation regions in the liquid slug and the liquid film development length. Therefore, a wide range parametric study of isolated gas Taylor bubbles flowing in co-current with liquid in circular milli- and microchannels is presented, in a wide range of Capillary (CaB) (0.01-2) and Reynolds numbers (ReB) (0.01-700). The shape and velocity of the bubbles are, together with the flow patterns in the flowing liquid, analyzed and compared with numerical and experimental correlations available in the literature. For low values of CaB, the streamlines (moving reference frame (MRF)) in the liquid slug show semi-infinite recirculations occupying a large portion of the cross-section of the channel. The mean velocity of the fluid moving inside the external envelope of the semi-infinite streamlines is equal to the bubble velocity. For high values of CaB, there are no recirculations and the bubble is moving faster or at least at the velocity of the liquid in the center of the tube; this flow pattern is often called bypass flow. The results also indicate that the liquid film surrounding the bubbles is for low CaB and ReB numbers almost stagnant, and its thickness accurately estimated with existing correlations. The stagnant film hypothesis developed provides an accurate approach to estimate the velocity of the bubble, in particular for low values of CaB. The asymptotic behavior of the studied parameters enables the extrapolation of data for CaB lower than 0.01. In addition to the simulations of isolated bubbles, simulations with two consecutive bubbles were also carried out; coalescence was only observed in very specific conditions. The results obtained in this study are directly applicable to co-current slug flow in milli- and microchannels for 0.1 < ReB < 1000 and 0.02 < CaB < 2. [ABSTRACT FROM AUTHOR]

Cell therapy is a promising approach to improve cartilage healing. Adipose tissue is an abundant and readily accessible cell source. Previous studies have demonstrated good cartilage repair results with adipose tissue mesenchymal stem cells in small animal experiments. This study aimed to examine these cells in a large animal model. Thirty knees of adult sheep were randomly allocated to three treatment groups: CELLS (scaffold seeded with human adipose tissue mesenchymal stem cells), SCAFFOLD (scaffold without cells), or EMPTY (untreated lesions). A partial thickness defect was created in the medial femoral condyle. After six months, the knees were examined according to an adaptation of the International Cartilage Repair Society (ICRS 1) score, in addition to a new Partial Thickness Model scale and the ICRS macroscopic score. All of the animals completed the follow-up period. The CELLS group presented with the highest ICRS 1 score (8.3 ± 3.1), followed by the SCAFFOLD group (5.6 ± 2.2) and the EMPTY group (5.2 ± 2.4) (p = 0.033). Other scores were not significantly different. These results suggest that human adipose tissue mesenchymal stem cells promoted satisfactory cartilage repair in the ovine model. [ABSTRACT FROM AUTHOR]

Microfluidic devices are electrical/mechanical systems that offer the ability to work with minimal sample volumes, short reactions times, and have the possibility to perform massive parallel operations. An important application of microfluidics is blood rheology in microdevices, which has played a key role in recent developments of lab-on-chip devices for blood sampling and analysis. The most popular and traditional method to fabricate these types of devices is the polydimethylsiloxane (PDMS) soft lithography technique, which requires molds, usually produced by photolithography. Although the research results are extremely encouraging, the high costs and time involved in the production of molds by photolithography is currently slowing down the development cycle of these types of devices. Here we present a simple, rapid, and low-cost nonlithographic technique to create microfluidic systems for biomedical applications. The results demonstrate the ability of the proposed method to perform cell free layer (CFL) measurements and the formation of microbubbles in continuous blood flow. [ABSTRACT FROM AUTHOR]

This paper reports the numerical and experimental analysis of the acoustic streaming effect in a fluidic domain. The actuation of a piezoelectric transducer generates acoustic waves that propagate to the fluids, generating pressure gradients that induce the flow. The number and positioning of the transducers affect the pressure gradients and, consequently, the resultant flow profile. Two actuation conditions were considered: (1) acoustic streaming generated by a 28 μm thick β-poly(vinylidene fluoride) (β-PVDF) piezoelectric transducer placed asymmetrically relative to the fluidic domain and (2) acoustic streaming generated by two 28 μm thick β-PVDF piezoelectric transducers placed perpendicularly to each other. The transducers were fixed to the lower left corner of a poly(methyl methacrylate) (PMMA)cuvette and were actuated with a 24 Vpp and 34.2 MHz sinusoidal voltage. The results show that the number of transducers and their positioning affects the shape and number of recirculation areas in the acoustic streaming flows. The obtained global flows show great potential for mixing and pumping, being an alternative to the previous geometries studied by the authors, namely, a single transducer placed symmetrically under a fluidic domain. [ABSTRACT FROM AUTHOR]

A linear electromagnetic energy harvesting device for underwater applications, fabricated with a simple manufacturing process, was developed to operate with movement frequencies from 0.1 to 0.4 Hz. The generator has two coils, and the effect of the combination of the two coils was investigated. The experimental study has shown that the energy capture system was able to supply energy to several ocean sensors, producing 7.77 mJ per second with wave movements at 0.4 Hz. This study shows that this energy is enough to restore the energy used by the battery or the capacitor and continue supplying energy to the sensors used in the experimental work. For an ocean wave frequency of 0.4 Hz, the generator can supply power to 8 sensors or 48 sensors, depending on the energy consumed and its optimization. [ABSTRACT FROM AUTHOR]

This study addresses the combination of customized surface modification with the use of nanofluids, to infer on its potential to enhance pool-boiling heat transfer. Hydrophilic surfaces patterned with superhydrophobic regions were developed and used as surface interfaces with different nanofluids (water with gold, silver, aluminum and alumina nanoparticles), in order to evaluate the effect of the nature and concentration of the nanoparticles in bubble dynamics and consequently in heat transfer processes. The main qualitative and quantitative analysis was based on extensive post-processing of synchronized high-speed and thermographic images. To study the nucleation of a single bubble in pool boiling condition, a numerical model was also implemented. The results show an evident benefit of using biphilic patterns with well-established distances between the superhydrophobic regions. This can be observed in the resulting plot of the dissipated heat flux for a biphilic pattern with seven superhydrophobic spots, δ = 1/d and an imposed heat flux of 2132 w/m2. In this case, the dissipated heat flux is almost constant (except in the instant t* ≈ 0.9 when it reaches a peak of 2400 W/m2), whilst when using only a single superhydrophobic spot, where the heat flux dissipation reaches the maximum shortly after the detachment of the bubble, dropping continuously until a new necking phase starts. The biphilic patterns also allow a controlled bubble coalescence, which promotes fluid convection at the hydrophilic spacing between the superhydrophobic regions, which clearly contributes to cool down the surface. This effect is noticeable in the case of employing the Ag 1 wt% nanofluid, with an imposed heat flux of 2132 W/m2, where the coalescence of the drops promotes a surface cooling, identified by a temperature drop of 0.7 °C in the hydrophilic areas. Those areas have an average temperature of 101.8 °C, whilst the average temperature of the superhydrophobic spots at coalescence time is of 102.9 °C. For low concentrations as the ones used in this work, the effect of the nanofluids was observed to play a minor role. This can be observed on the slight discrepancy of the heat dissipation decay that occurred in the necking stage of the bubbles for nanofluids with the same kind of nanoparticles and different concentration. For the Au 0.1 wt% nanofluid, a heat dissipation decay of 350 W/m2 was reported, whilst for the Au 0.5 wt% nanofluid, the same decay was only of 280 W/m2. The results of the numerical model concerning velocity fields indicated a sudden acceleration at the bubble detachment, as can be qualitatively analyzed in the thermographic images obtained in this work. Additionally, the temperature fields of the analyzed region present the same tendency as the experimental results. [ABSTRACT FROM AUTHOR]

A Computation Fluid Dynamics (CFD) study for micro-scale gas–liquid flow was performed by using two different software packages: OpenFOAM® and ANSYS Fluent®. The numerical results were compared to assess the capability of both options to accurately predict the hydrodynamics of this kind of system. The focus was to test different methods to solve the gas–liquid interface, namely the Volume of Fluid (VOF) + Piecewise Linear Interface Calculation (PLIC) (ANSYS Fluent®) and MULES/isoAdvector (OpenFOAM®). For that, a single Taylor bubble flowing in a circular tube was studied for different co-current flow conditions (0.01 < CaB < 2.0 and 0.01 < ReB < 700), creating representative cases that exemplify the different sub-patterns already identified in micro-scale slug flow. The results show that for systems with high Capillary numbers (CaB > 0.8) each software correctly predicts the main characteristics of the flow. However, for small Capillary numbers (CaB < 0.03), spurious currents appear along the interface for the cases solved using OpenFOAM®. The results of this work suggest that ANSYS Fluent® VOF+PLIC is indeed a good option to solve biphasic flows at a micro-scale for a wide range of scenarios becoming more relevant for cases with low Capillary numbers where the use of the solvers from OpenFoam® are not the best option. Alternatively, improvements and/or extra functionalities should be implemented in the OpenFOAM® solvers available in the installation package. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the initial events of Escherichia coli adhesion to polydimethylsiloxane, which is critical for the development of antifouling surfaces. A parallel plate flow cell was used to perform the initial adhesion experiments under controlled hydrodynamic conditions (shear rates ranging between 8 and 100/s), mimicking biomedical scenarios. Initial adhesion studies capture more accurately the cell-surface interactions as in later stages, incoming cells may interact with the surface but also with already adhered cells. Adhesion rates were calculated and results shown that after some time (between 5 and 9 min), these rates decreased (by 55% on average), from the initial values for all tested conditions. The common explanation for this decrease is the occurrence of hydrodynamic blocking, where the area behind each adhered cell is screened from incoming cells. This was investigated using a pair correlation map from which two-dimensional histograms showing the density probability function were constructed. The results highlighted a lower density probability (below 4.0 × 10−4) of the presence of cells around a given cell under different shear rates irrespectively of the radial direction. A shadowing area behind the already adhered cells was not observed, indicating that hydrodynamic blocking was not occurring and therefore it could not be the cause for the decreases in cell adhesion rates. Afterward, cell transport rates from the bulk solution to the surface were estimated using the Smoluchowski-Levich approximation and values in the range of 80–170 cells/cm2.s were obtained. The drag forces that adhered cells have to withstand were also estimated and values in the range of 3–50 × 10−14 N were determined. Although mass transport increases with the flow rate, drag forces also increase and the relative importance of these factors may change in different conditions. This work demonstrates that adjustment of operational parameters in initial adhesion experiments may be required to avoid hydrodynamic blocking, in order to obtain reliable data about cell-surface interactions that can be used in the development of more efficient antifouling surfaces. [ABSTRACT FROM AUTHOR]

Intestinal mucositis, characterized by inflammatory and/or ulcerative processes in the gastrointestinal tract, occurs due to cellular and tissue damage following treatment with 5-fluorouracil (5-FU). Rutin (RUT), a natural flavonoid extracted from Dimorphandra gardneriana, exhibits antioxidant, anti-inflammatory, cytoprotective, and gastroprotective properties. However, the effect of RUT on inflammatory processes in the intestine, especially on mucositis promoted by antineoplastic agents, has not yet been reported. In this study, we investigated the role of RUT on 5-FU-induced experimental intestinal mucositis. Swiss mice were randomly divided into seven groups: Saline, 5-FU, RUT-50, RUT-100, RUT-200, Celecoxib (CLX), and CLX + RUT-200 groups. The mice were weighed daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis); malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH) concentrations; mast and goblet cell counts; and cyclooxygenase-2 (COX-2) activity, as well as to perform immunohistochemical analyses. RUT treatment (200 mg/kg) prevented 5-FU-induced histopathological changes and reduced oxidative stress by decreasing MDA concentrations and increasing GSH concentrations. RUT attenuated the inflammatory response by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. These results suggest that the COX-2 pathway is one of the underlying protective mechanisms of RUT against 5-FU-induced intestinal mucositis. [ABSTRACT FROM AUTHOR]

Air inside of blood vessels is a phenomenon known as gas embolism. During the past years, studies have been performed to assess the influence of air bubbles in microcirculation. In this study, we investigated the flow of bubbles in a microchannel network with several bifurcations, mimicking part of a capillary system. Thus, two working fluids were used, composed by sheep red blood cells (RBCs) suspended in a Dextran 40 solution with different hematocrits (5% and 10%). The experiments were carried out in a polydimethylsiloxane (PDMS) microchannel network fabricated by a soft lithography. A high-speed video microscopy system was used to obtain the results for a blood flow rate of 10 µL/min. This system enables the visualization of bubble formation and flow along the network. The results showed that the passage of air bubbles strongly influences the cell's local concentration, since a higher concentration of cells was observed upstream of the bubble, whereas a lower local hematocrit was visualized at the region downstream of the bubble. In bifurcations, bubbles may split asymmetrically, leading to an uneven distribution of RBCs between the outflow branches. [ABSTRACT FROM AUTHOR]

Slug flow is a multiphase flow pattern characterized by the occurrence of long gas bubbles (Taylor bubbles) separated by liquid slugs. This multiphase flow regime is present in many and diversified natural and industrial processes, at macro and microscales, such as in eruption of volcanic magmas, oil recovery from pre-salt regions, micro heat exchangers, and small-sized refrigerating systems. Previous studies in the literature have been mostly focused on tubular gas bubbles flowing in Newtonian liquids. In this work, results from several numerical simulations of tubular gas bubbles flowing in a shear thinning liquid in microchannels are reported. To simulate the shear thinning behavior, carboxymethylcellulose (CMC) solutions with different concentrations were considered. The results are compared with data from bubbles flowing in Newtonian liquids in identical geometric and dynamic conditions. The numerical work was carried out in computational fluid dynamics (CFD) package Ansys Fluent (release 16.2.0) employing the volume of fluid (VOF) methodology to track the volume fraction of each phase and the continuum surface force (CSF) model to insert the surface tension effects. The flow patterns, the viscosity distribution in the liquid, the liquid film thickness between the bubble and the wall, and the bubbles shape are analyzed for a wide range of shear rates. In general, the flow patterns are similar to those in Newtonian liquids, but in the film, where a high viscosity region is observed, the thickness is smaller. Bubble velocities are smaller for the non-Newtonian cases. [ABSTRACT FROM AUTHOR]

Two-phase flows are found in several industrial systems/applications, including boilers and condensers, which are used in power generation or refrigeration, steam generators, oil/gas extraction wells and refineries, flame stabilizers, safety valves, among many others. The structure of these flows is complex, and it is largely governed by the extent of interphase interactions. In the last two decades, due to a large development of microfabrication technologies, many microstructured devices involving several elements (constrictions, contractions, expansions, obstacles, or T-junctions) have been designed and manufactured. The pursuit for innovation in two-phase flows in these elements require an understanding and control of the behaviour of bubble/droplet flow. The need to systematize the most relevant studies that involve these issues constitutes the motivation for this review. In the present work, literature addressing gas-liquid and liquid-liquid flows, with Newtonian and non-Newtonian fluids, and covering theoretical, experimental, and numerical approaches, is reviewed. Particular focus is given to the deformation, coalescence, and breakup mechanisms when bubbles and droplets pass through the aforementioned microfluidic elements. [ABSTRACT FROM AUTHOR]

Intestinal mucositis is a common complication associated with 5-fluorouracil (5-FU), a chemotherapeutic agent used for cancer treatment. Troxerutin (TRX), a semi-synthetic flavonoid extracted from Dimorphandra gardneriana, has been reported as a potent antioxidant and anti-inflammatory agent. In the present study, we aimed to evaluate the effect of TRX on 5-FU-induced intestinal mucositis. Swiss mice were randomly divided into seven groups: Saline, 5-FU, TRX-50, TRX-100, TRX-150, Celecoxib (CLX), and CLX + TRX-100. The weight of mice was measured daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis), levels of malondialdehyde (MDA), myeloperoxidase (MPO), glutathione (GSH), mast and goblet cell counts, immunohistochemical analysis, and cyclooxygenase-2 (COX-2) activity. Compared to the saline treatment, the 5-FU treatment induced intense weight loss and reduction in villus height. TRX treatment (100 mg/kg) prevented the 5-FU-induced histopathological changes and decreased oxidative stress by decreasing the MDA levels and increasing GSH concentration. TRX attenuated inflammatory process by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. TRX also reversed the depletion of goblet cells. Our findings suggest that TRX at a concentration of 100 mg/kg had chemopreventive effects on 5-FU-induced intestinal mucositis via COX-2 pathway. [ABSTRACT FROM AUTHOR]

Since the first microfluidic device was developed more than three decades ago, microfluidics is seen as a technology that exhibits unique features to provide a significant change in the way that modern biology is performed. Blood and blood cells are recognized as important biomarkers of many diseases. Taken advantage of microfluidics assets, changes on blood cell physicochemical properties can be used for fast and accurate clinical diagnosis. In this review, an overview of the microfabrication techniques is given, especially for biomedical applications, as well as a synopsis of some design considerations regarding microfluidic devices. The blood cells separation and sorting techniques were also reviewed, highlighting the main achievements and breakthroughs in the last decades. [ABSTRACT FROM AUTHOR]

Intestinal mucositis is a common complication associated with 5-fluorouracil (5-FU), a chemotherapeutic agent used for cancer treatment. Cashew gum (CG) has been reported as a potent anti-inflammatory agent. In the present study, we aimed to evaluate the effect of CG extracted from the exudate of Anacardium occidentale L. on experimental intestinal mucositis induced by 5-FU. Swiss mice were randomly divided into seven groups: Saline, 5-FU, CG 30, CG 60, CG 90, Celecoxib (CLX), and CLX + CG 90 groups. The weight of mice was measured daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis), levels of malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH), and immunohistochemical analysis of interleukin 1 beta (IL-1β) and cyclooxygenase-2 (COX-2). 5-FU induced intense weight loss and reduction in villus height compared to the saline group. CG 90 prevented 5-FU-induced histopathological changes and decreased oxidative stress through decrease of MDA levels and increase of GSH concentration. CG attenuated inflammatory process by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. Our findings suggest that CG at a concentration of 90 mg/kg reverses the effects of 5-FU-induced intestinal mucositis. [ABSTRACT FROM AUTHOR]

Malaria is one of the leading causes of death in underdeveloped regions. Thus, the development of rapid, efficient, and competitive diagnostic techniques is essential. This work reports a study of the deformability and velocity assessment of healthy and artificially impaired red blood cells (RBCs), with the purpose of potentially mimicking malaria effects, in narrow polydimethylsiloxane microchannels. To obtain impaired RBCs, their properties were modified by adding, to the RBCs, different concentrations of glucose, glutaraldehyde, or diamide, in order to increase the cells' rigidity. The effects of the RBCs' artificial stiffening were evaluated by combining image analysis techniques with microchannels with a contraction width of 8 µm, making it possible to measure the cells' deformability and velocity of both healthy and modified RBCs. The results showed that healthy RBCs naturally deform when they cross the contractions and rapidly recover their original shape. In contrast, for the modified samples with high concentration of chemicals, the same did not occur. Additionally, for all the tested modification methods, the results have shown a decrease in the RBCs' deformability and velocity as the cells' rigidity increases, when compared to the behavior of healthy RBCs samples. These results show the ability of the image analysis tools combined with microchannel contractions to obtain crucial information on the pathological blood phenomena in microcirculation. Particularly, it was possible to measure the deformability of the RBCs and their velocity, resulting in a velocity/deformability relation in the microchannel. This correlation shows great potential to relate the RBCs' behavior with the various stages of malaria, helping to establish the development of new diagnostic systems towards point-of-care devices. [ABSTRACT FROM AUTHOR]

Techniques, such as micropipette aspiration and optical tweezers, are widely used to measure cell mechanical properties, but are generally labor-intensive and time-consuming, typically involving a difficult process of manipulation. In the past two decades, a large number of microfluidic devices have been developed due to the advantages they offer over other techniques, including transparency for direct optical access, lower cost, reduced space and labor, precise control, and easy manipulation of a small volume of blood samples. This review presents recent advances in the development of microfluidic devices to evaluate the mechanical response of individual red blood cells (RBCs) and microbubbles flowing in constriction microchannels. Visualizations and measurements of the deformation of RBCs flowing through hyperbolic, smooth, and sudden-contraction microchannels were evaluated and compared. In particular, we show the potential of using hyperbolic-shaped microchannels to precisely control and assess small changes in RBC deformability in both physiological and pathological situations. Moreover, deformations of air microbubbles and droplets flowing through a microfluidic constriction were also compared with RBCs deformability. [ABSTRACT FROM AUTHOR]

With a broad ethnopharmacological tradition in Brazil, Montrichardia linifera has been reported as a potent antirheumatic, antimicrobial, and antiprotozoan agent. However, there is a lack of studies on its effect on bacterial biofilm formation and Schistosoma mansoni worms. This study reports the effects of antibacterial, antibiofilm, and antischistosomal properties of leaf extracts of M. linifera. Phytochemical screening and identification of the main compounds of the extracts were performed. All the extracts evaluated showed antibacterial activity at the concentrations tested. We checked for the presence of flavonoids and derivatives of phenolic acids by the presence of spectra with bands characteristic of these classes in the sample analyzed. The antibacterial assays showed that the best MICs corresponded to 125 μg/mL against Enterococcus faecalis ATCC 29212 in all fractions. The ethanolic and methanolic extracts showed the ability to inhibit biofilm of Staphylococcus aureus ATCC 25123. For the antischistosomal activity, only the acetone and ethyl acetate extracts had a significant effect against helminths, with potent activity at a concentration of 50 μg/mL, killing 100% of the worms after 72 h of incubation. The M. linifera leaf extracts showed antibacterial activity, biofilm inhibition capacity, and anthelmintic activity against S. mansoni. [ABSTRACT FROM AUTHOR]

Intestinal mucositis is a common complication associated with 5-fluorouracil (5-FU), a chemotherapeutic agent used for cancer treatment. Cashew gum (CG) has been reported as a potent anti-inflammatory agent. In the present study, we aimed to evaluate the effect of CG extracted from the exudate of Anacardium occidentale L. on experimental intestinal mucositis induced by 5-FU. Swiss mice were randomly divided into seven groups: Saline, 5-FU, CG 30, CG 60, CG 90, Celecoxib (CLX), and CLX + CG 90 groups. The weight of mice was measured daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis), levels of malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH), and immunohistochemical analysis of interleukin 1 beta (IL-1β) and cyclooxygenase-2 (COX-2). 5-FU induced intense weight loss and reduction in villus height compared to the saline group. CG 90 prevented 5-FU-induced histopathological changes and decreased oxidative stress through decrease of MDA levels and increase of GSH concentration. CG attenuated inflammatory process by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. Our findings suggest that CG at a concentration of 90 mg/kg reverses the effects of 5-FU-induced intestinal mucositis., Competing Interests: The authors declare no conflict of interest.

Techniques, such as micropipette aspiration and optical tweezers, are widely used to measure cell mechanical properties, but are generally labor-intensive and time-consuming, typically involving a difficult process of manipulation. In the past two decades, a large number of microfluidic devices have been developed due to the advantages they offer over other techniques, including transparency for direct optical access, lower cost, reduced space and labor, precise control, and easy manipulation of a small volume of blood samples. This review presents recent advances in the development of microfluidic devices to evaluate the mechanical response of individual red blood cells (RBCs) and microbubbles flowing in constriction microchannels. Visualizations and measurements of the deformation of RBCs flowing through hyperbolic, smooth, and sudden-contraction microchannels were evaluated and compared. In particular, we show the potential of using hyperbolic-shaped microchannels to precisely control and assess small changes in RBC deformability in both physiological and pathological situations. Moreover, deformations of air microbubbles and droplets flowing through a microfluidic constriction were also compared with RBCs deformability., Competing Interests: The authors declare no conflict of interest.