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Strategies to encapsulate natural extracts in lipid-based nanocarriers

Numerous plant species possess bioactive properties, with algae emerging as particularly noteworthy due to their distinctive characteristics that pique the interest of diverse industries. For instance, the pharmaceutical industry is greatly interested in features like neuroprotective, anti-glycemic, and cytotoxic qualities found in some algal species. Nonetheless, it is imperative to devise efficient systems capable of effectively releasing bioactive compounds present in these extracts. In this regard, nanoparticles have garnered considerable attention across various fields, particularly in drug delivery applications.

Lipid-based nanoparticles have emerged as a promising solution, offering numerous advantages. These nanoparticles exhibit high biocompatibility and biodegradability, making them suitable for use in biological systems. Additionally, they possess the ability to encapsulate both hydrophilic and hydrophobic drugs, thereby expanding their versatility. One remarkable attribute of lipid-based nanoparticles is their capability to traverse the blood-brain barrier, a crucial physical barrier responsible for regulating the entry of chemicals into the brain and maintaining central nervous system homeostasis. Overcoming this barrier presents a significant challenge in the treatment of central nervous system disorders.

Therefore, this study aims to provide an overview of the latest advancements in the nanoencapsulation of natural extracts using lipid-based vesicular delivery systems. The investigation into lipid-based nanoparticles as carriers for bioactive substances holds great promise in developing effective therapies for various ailments, particularly those affecting the central nervous system.

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Current developments on friction stir welding (FSW) and friction stir spot welding (FSSW) of aluminium and titanium alloys

To fabricate joints of dissimilar materials such as alumnium and titanium with excellent joint properties with limited defects, there is a need to use effective joining techniques. Friction stir welding (FSW) and friction stir spot welding (FSSW) are solid-state welding techniques considered environmentally friendly joining techniques. The two techniques have been used to join numerous materials including aluminium, copper, and titanium. Joining dissimilar materials has seen a huge expansion worldwide due to the high demand for dissimilar joining exhibiting specific properties to be used for specific applications. This short review presents the resulting properties of joints made with aluminium and copper using friction stir welding and friction stir welding. Microstructure evolution, mechanical properties, and other properties are presented and critically reviewed. Many aluminium and titanium alloys have been welded using several process parameters and tool geometries. In FSW it has been seen that aluminium/titanium exhibited high strength when the rotational speed is well controlled. From the gathered information it was concluded that the tool rotational speed was associated with heat input and low speed resulting in low heat input. This produced fine recrystallized grains, especially at the joint interface. On the other hand, FSSW has also been utilized to weld Al to Ti. Results showed that parameters such as rotational speed and dwell time had an impact on the formation of intermetallics including Ti3Al and mechanical properties were achieved. It was observed that FSSW between aluminium and titanium has not been well researched, therefore there is a need to further study the behavior of the two materials when spot welded. It is expected that the augmentation of knowledge on the fabricated joint behavior will lead to the expansion of these techniques for specific applications and to the optimization of FSW and FSSW between alumnium and titanium alloys.

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Estimation of water potential in corn plants using machine learning techniques with UAV imagery and evaluating the effect of flight height

The use of unmanned aerial vehicles (UAVs) in precision agriculture has proven to be a useful tool for crop monitoring. The use of this technology in irrigation water management represents a significant improvement opportunity compared to the tools commonly used. This study aimed to estimate the water content in corn plants using images captured by a drone, evaluating the effect that the flight height has on the accuracy of the estimation of this indicator. For this purpose, the water potential (WP) was measured in corn plant leaves, which allows inferring the presence of water stress and indicating the need for irrigation in the plant. Aerial images of the crop were captured under three treatments based on irrigation levels (40%, 70%, and 100% water applied compensating for evapotranspiration) to induce gradients of moisture content in the plants. Seven drone flights were carried out at different dates at 30, 50 and 70 m high. The water potential of the leaves was correlated with radiometrically calibrated multispectral images (R, G, B, red-edge, and near-infrared). Three models were developed: a multiple linear regression (LM), neural networks (NN), and a random forest (RF). The LM and NN models showed similar error metrics, with the RF model showing the best results, with an average root mean square error (RMSE) and coefficient of determination (R2) of 2.45 and 0.94, respectively. The flight height, which affected the resolution of the images, was not significant in the estimation of WP in this height range.

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Improving the stability of an integrated power system with stochastic renewable source energies and Hybrid Power Flow Controller using a multi-Band power system stabilizer
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Ensuring the stability of the electrical system throughout its operation is becoming a major challenge, particularly with the increase in electricity demand, the change in the topology of electrical networks and the insertion of renewable energies. This can be ensured by the introduction of flexible AC transmission systems (FACTS), such as hybrid power flow controllers (HPFC) which alternate unified power flow controllers (UPFC). The HPFC controller, with its more economical aspect, must control the real power and regulate the voltage in the electrical networks. It can also separately control the total reactive power exchanged with the transmitting and receiving ends of the line. Several HPFC topologies are used in electrical engineering. It can consist of two synchronous static compressors (SSSC) connected in series, and in shunt with a static voltage compensator (SVC). As it can consist of two shunt static compensators (STATCOM), connected by a thyristor controlled series compensator (TCSC) through a coupling transformer in a common DC link. This manuscript presents the efficiency of inserting the multiband power system stabilizer (MB-PSS) into a power grid integrated by wind and solar sources, and controlled by a hybrid power flow controller (HPFC). The analysis is established on a kundur multi-machine system with 4 generators and 11 nodes. The curves of the voltages at the nodes between the two zones and the curves of the active and reactive powers transmitted from one zone to the other are produced using the Matlab/simulink software.

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Comparative analysis of the approach of different countries to the standards of the bridge structures condition management system

The work examines the control systems of bridge structures, which are used to assess the condition, forecast repair works and optimize costs. Bridge management is a key element of infrastructure systems in many countries, as it ensures safety, efficiency and economic development. Examples of such systems as Pontis, Bridgit, Danbro and etc. are presented, which are used in different countries to assess the condition of bridges and plan repair works. The importance of safety and optimal operation of bridge structures is highlighted. It is highlighted that bridge management systems are necessary tools for countries with different operation and maintenance strategies. The importance of rational management of bridges to ensure safety and sustainable development of transport networks is brought to the fore.

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Determination of the dynamic behaviour of thin-walled hollow-box sandwich beams

Sandwich geometries, mainly panels and beams are widely used in several transportation industries, namely aerospace, aeronautic and automotive. They are known for some advantages in structural applications: high specific stiffness, low weight, and possibility of design optimization prior to manufacturing. This study aims to discover the dynamic behaviour of simply supported at its ends Finite Element Method (FEM) models, representing a novel type of sandwich beams. There are 24 examples of geometries discussed with the same base configuration. The models were previously subjected to a design optimization routine. Dynamic behaviour of the initial models in relation to their final versions is considered. Influence of the geometry on the characteristic frequencies is discussed, as well as its improvement in relation to the initial models. It is shown that the statically optimized models represent a significant improvement over the initial ones, as some improvement of the characteristic frequencies is obtained for most cases. By improvement here it is understood their values for the optimized model are higher than those for the corresponding initial one. In fact, the frequencies are more energetic the lower they are. As such, lower values represent higher probability of disturbance of the correct operation of the beams in applications comprising mobile parts. Some example of such application can be laser cutting machines or industrial printers.

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Predicting the NACA0012-IK30 Airfoil Propulsive Capabilities with a Panel Method

Studying flapping airfoils' aerodynamics is essential to examine several engineering problems such as rotor blade design and bioinspired solutions for flight. However, the study of oscillating airfoils is a complex topic governed by several parameters that create a massive domain space, requiring considerable computational resources. Therefore it is necessary to develop and use Reduced Order Models (ROMs) which can still provide good results while maintaining the computational burden low. With this objective in mind, the present work uses a panel code to study the aerodynamics of an oscillating airfoil. Its geometry is based on an innovative geometry which is a modified version of the traditional NACA0012 airfoil. We call it the NACA0012-IK30 airfoil, and its main feature is the capability of dynamically deflecting the leading-edge part independently from the rest of the airfoil body. The panel code is implemented in MATLAB and is based on the Hess-Smith Panel Method (HSPM). Additionally, to verify the panel code efficacy, we compare its results with some conditions simulated using high-fidelity CFD computations. Results present a comparison between the panel code and CFD computations of the propulsive power and required power coefficients. While the propulsive power is overestimated by the panel method, the required power which is linked to lift production, is not. In fact, the panel code offers a good approximation of CFD data, despite massive flow separation that is not captured by the potential flow. The pressure distribution on the airfoil is also used to compare the efficacy of the panel code, which ignoring the commonly known artifacts of potential flow, can capture some of the pressure distribution features. More research should be conducted to further improve the panel code by modifying it or adding some features that emulate flow separation. Such an approach will offer a great starting point for flapping wings while maintaining the computation effort at a low level.

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Static Stability Analysis of Bamboo Grid-reinforced Slopes

The limit equilibrium method (LEM) is an analytical technique presented in this study to examine the stability of bamboo grid-reinforced slopes. The so-called Horizontal Slice Method (HSM) is used to replicate horizontal bamboo grid layers. Each bamboo grid layer functions as a beam, offering axial strength and resistance to bending and shear. A formula is created by selecting pertinent governing equilibrium equations that are fitted to the novel notion used only for the study of bamboo grid-reinforced slopes. For slopes with varying features, parametric tests are carried out to assess the impacts of raising the bamboo grid height and substituting geogrids with bamboo grids of different heights. As a result, the stability condition is enhanced, and a less extensive reinforcement system is created, according to the results, which revealed that doing such steps would reasonably lower the needed tension and length of the reinforcement layers. The dependence of the output values on the slope angle and the material characteristics.

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Title: Electrical Characterization of Cu-Doped PEDOT: PSS Polymeric Thin Films

Abstract: This study investigates the electrical properties of Cu-doped PEDOT:PSS samples using electrical methods, including Hall measurements. Cu doping enhances the conductivity of PEDOT:PSS, making it promising for organic electronics. Different samples were prepared by spin coating method and characterized for Hall mobility, carrier concentration, and electrical conductivity using the Hall measurements. The sheet resistance was measured to determine electrical conductivity, aided by knowledge of the thin film thickness. Temperature dependency was also evaluated using a closed cycle cryostat, covering temperatures ranging from 4 K to 300 K. These comprehensive measurements provide valuable insights into the electrical behavior and temperature characteristics of Cu-doped PEDOT:PSS, facilitating the development of high-performance organic electronic devices.

Figure 1 illustrates the results for the temperature dependence of DMSO-doped PEDOT:PSS using temperature-dependent Hall measurements. The figure demonstrates an increase in electrical conductivity with increasing temperature.

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Energy Optimized Edge Computing Framework for the Sustainable Development of Modern Agriculture

The effects of climate change has a direct impact on the crop production as the environmental conditions become unsatisfactory to support the proper growth of crops, this can lead to severe economic loss and create a backlog in the food production. Smart agriculture has proven to be an effective solution in maximising the crop yield while ensuring sustainable farming by alleviating the consequences of traditional agricultural practices. As effective as it may be, implementation of this is confronted with various challenges such as lack of infrastructure and isolation from networking facilities that are required for the smooth operation of the Wireless Sensor Network established. The sensors and imaging systems present in the cropland generate large amounts of data that need to be processed in an affordable and scalable manner even when the internet connection is limited. Edge computing is an emerging technology that is capable of processing data close to the user and can thus reduce the latency and provide functional capabilities even in the absence of sufficient internet bandwidth. This paper proposes an architecture that utilizes agricultural waste to power the edge devices being deployed in a given crop land. In order to ensure efficient energy usage and processing we implement the DBSCAN clustering algorithm integrated with the FPKM algorithm to efficiently denoise the collected data and an offloading mechanism that ensures efficient usage of computational resources by enabling parallel computation to minimize errors and delays in actuator instructions that could potentially increase the crop productivity and significantly diminish the possibility of crop loss.

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