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The effectiveness of impulsive jet fans ventilation on CO concentration in closed car park

ABSTRACT As there is a risk of CO contamination by vehicles running inside the car park. This research was initiated with the objective of assessing jet fans' impulsive ventilation “IV” performance and studying its effect on CO contamination in such garages, where a 1350 m2 UG (2.65 m high) was considered as a case study. 39 scenarios were proposed; visualized in a matrix, and simulated by a Computational Fluid Dynamics “CFD” model (ANSYS FLUENT 2019 R3), natural ventilation, and impulsive ventilation were studied. The proposed scenarios considered the jet fans “JFs” arrangement, in terms of number and interspacing and location within the garage, flow of JFs, and load capacity, in terms of the number of cars in operation. A code notation was made to describe each case's properties. The results highlighted valuable insights into the optimal arrangement of jet fans in UG. It flagged the importance of adjusting the number of fans, spacing, and location to attain reasonable ventilation performance. The research suggested implementing an inverter variable speed drive in the ventilation system to provide 6 or 10 ACH and adjusting them based on UG occupancy whether at normal load or peak load, Additionally, the On-Off system allows for the utilization of different arrangements according to the load requirements. A collective correlation was attempted to identify the values of CO in PPM according to load percentage and ACH.

Fabrication of a Superhydrophobic RGO Coated-Polyurethan Sponge for Removing Oil, Organic Solvent, and Gasoline from Water

In recent years, the issue of oil and organic spillage caused by human population growth has become increasingly urgent, not only in Vietnam but also worldwide. Researchers are showing great interest in the research and development of materials capable of selectively absorbing oils and organic solvents while repelling water. In this project, an oil-absorbing material was developed using reduced graphene oxide particles incorporated into a polyurethane (PU) foam base. Utilizing PU sponge as the base material enhances the oil absorption capacity of the material. Graphene oxide was initially synthesized using the Hummers method and then reduced with ascorbic acid to form reduced graphene oxide (RGO). RGO was applied to the sponge with varying loading amounts, ranging from 0 to 254%. Subsequently, the porous material was coated with high-density polyethylene (HDPE) to assess its hydrophobicity and its ability to adsorb oil and organic solvents. The results indicate that the oil and organic solvent absorption capacity of RGO and HDPE coating materials is highest at RGO loading percentages exceeding 64%, yielding absorption rates ranging from 35 to 63 times the weight of the material. Additionally, the contact angle of RGO and HDPE coating materials is approximately 150°, demonstrating the high hydrophobicity of the material.

Flexible Phase Change Materials with High Energy Storage Density Based on Porous Carbon Fibers.

Phase change fibers (PCFs) can effectively store and release heat, improve energy efficiency, and provide a basis for a wide range of energy applications. Improving energy storage density and preserving flexibility are the primary issues in the efficient manufacture and application development of PCFs. Herein, we have successfully fabricated a suite of flexible PCFs with high energy storage density, which use hollow carbon fibers (HCFs) encapsulated phase change materials (PCMs) to provide efficient heat storage and release, thereby enhancing energy efficiency and underpinning a broad range of energy applications. The flexible HCF/LA PCFs with high energy density were made by impregnating a small molecule LA solution, whereas the precursor of the PAN/ZIF-67 composite fibers was created by electrospinning. These PCFs have a high loading capacity for lauric acid (LA), demonstrating a 92% load percentage and a 153 J g-1 phase change enthalpy value. The effects of doping quantity (ZIF-67), fiber orientation, pre-oxidation treatment, and particle size on the morphological and structural characteristics of HCFs, as well as the impact of HCFs' pore structure on PCM encapsulation, were investigated. It was found that the oriented fiber structure serves to reduce the likelihood of fracture and breakage of precursor fibers after carbonization, whilst the gradient pre-oxidation can maintain the original fiber morphology of the fibers after carbonization. These findings establish a solid theoretical foundation for the design and production of high-performance flexible porous carbon nanofiber wiping phase change composites.

Optimization of Noise Emission Level in Diesel Engine with Biodiesel Application Using Response Surface Methodology

This study used biodiesel to run a single-cylinder direct-injection diesel engine. The palm oil methyl ester is blended in different ratios of up to 20% and tested with different engine speeds and loads for noise level measurement. Mathematical modeling was then developed to correlate responses obtained by the noise levels of the engine components to the factors, including engine speed, engine load, and biodiesel blending percentage. Finally, using the developed models, all the numeric factors were optimized. Modeling results indicated that the significance of factors could vary for the engine components, whereas in this study, the intake phase-related factors showed the significance of all factors. Meanwhile, the optimization results highlighted that the best solution with the highest desirability number to satisfy all the responses was the B20 fuel blend (20% biodiesel fuel and 80% diesel fuel blend by volume) with 1200 rpm of engine speed. In conclusion, the study's outcomes revealed that optimization should be considered in developing a new policy for using biofuel in internal combustion engines.

Preparation and in-vitro characterization of triamcinolone acetonide-loaded lipid liquid crystal nanocarriers for ocular delivery

Purpose: This study aimed to develop sustained-release Triamcinolone acetonide (TA) formulations using lipid liquid crystals (LLC) for ocular drug delivery and to characterize the designed formulations. Method: Eighteen dispersed LLC formulations were prepared through a top-down approach, incorporating varying concentrations of TA and different proportions of glyceryl monooleate, deionized water, and Pluronic F127. An additional formulation comprising TA: HPβCD complex was also developed to investigate the influence of hydroxypropyl beta-cyclodextrin (HPβCD) on the properties of the formulations. The formulations were evaluated for their rheological properties in room temperature using a rheometer, syringeability by passing them through a 27G needle, size measurements via dynamic light scattering, and morphology through polarized light microscopy (PLM). Furthermore, the prepared formulations were injected into a dialysis tube and placed in a phosphate buffer at pH 7.4 and 37°C for in vitro release evaluation. Samples were taken at predetermined intervals and stored in a refrigerator until HPLC analysis. The percentage of Encapsulation efficacy and drug loading were evaluated using an indirect method. A reversed-phase HPLC method was employed to quantify the drug concentrations in the samples. Results: All selected formulations demonstrated acceptable parameters, including particle size (less than 200 nm), polydispersity index ranging from 0.202 to 0.355, and zeta potential values between -14.3 and -32.8 mV. Additionally, the formulations showed good syringeability and achieved 100% drug release within 48 hours (except for the formulation containing HPβCD). PLM analysis revealed the presence of hexosomes and cubosomes, indicating that an increase in hexosomes contributed to a more uniform drug release from the formulations. Conclusion: Overall, the study findings suggest that liquid crystalline carriers can be a promising formulation for sustained ocular drug delivery of TA.

Novel Synthesis, and Application of Carboxymethylated Cassia fistula‐Based Hydrogel for Extended‐Release of Dinotefuran

AbstractThe agricultural industry prioritizes minimizing crop yield losses caused by pests, making it essential to develop effective, safe and sustainable pesticide formulations. Hydrogels are promising carriers for pesticide delivery, due to their high surface area, large pore volume, and pore size. In this study, we synthesized Cassia fistula (CA‐g‐AA) and its derivative carboxymethylated Cassia fistula‐grafted polysodium acrylate hydrogel (CMCA‐g‐AA) using free radical polymerization, with N, N'‐methylene bisacrylamide (MBA) as a crosslinker, for the ex‐situ encapsulation of dinotefuran. Characterization was performed using FTIR, 13C CPMAS‐NMR, SEM, TGA, rheology, and XRD. The maximum swelling capacity of hydrogels was investigated in distilled water. CA‐g‐AA and CMCA‐g‐AA hydrogels exhibited a dinotefuran loading percentage of 37 and 39% and released dinotefuran for 26 and 29 h, respectively. The dinotefuran release kinetics was analyzed by using the Korsmeyer‐Peppas and Higuchi models. Under drought like conditions, CMCA‐g‐AA‐treated soil sustained plant growth for 7 days, compared to CA‐g‐AA (5 days) and untreated soil (3 days). The novel hydrogel CMCA‐g‐AA enhanced soil water absorption and retention along with highlighting its potential for extended pesticide release. Thus, the developed CMCA‐g‐AA hydrogel is an efficient strategy for sustainable agriculture.

Analisis Kapasitas Produksi Menggunakan Metode Rough Cut Capacity Planning Pada CV Tahaki Multi Kreasi

CV Tahaki Multi Kreasi is a company engaged in interior, exterior and advertising. The number of requests for cabinet room products tends to fluctuate every month. In 2023, from January to December, CV Tahaki Multi Kreasi received 143 cabinet room order projects. To estimate the amount of demand, effective forecasting is needed. Forecasting uses methods namely Moving Average, Exponential Smoothing, and Trend Analysis. The most effective forecasting uses the Trend Analysis method which has the smallest forecasting error. The MAD value is 1.9005, MSE is 4.5343, and MAPE is 19.2362. The production schedule at CV Tahaki Multi Kreasi is carried out every two weeks for optimal results. Production capacity requirements are calculated using the Rough Cut Capacity Planning (RCCP) method. The RCCP method is used to determine the possibility of insufficient capacity or overload in determining production capacity.. The total capacity required in all work centers is 962 hours, while the total available capacity is 2016 hours. The analysis shows that there is no capacity shortage at each work station because the variance shows negative and the load percentage is 54.2%.

Polyethylene glycol/carboxymethyl cellulose/montmorillonite composite phase change materials for thermal management

The fabrication of composite phase change materials (CPCMs) with excellent shape stability, reasonable thermal conductivity and good mechanical properties using simple process to obtain an effective energy storage and conversion maintains an issue of the utmost importance. In this work, carboxymethylcellulose sodium (CMC)/montmorillonite (MMT) aerogels with various MMT loading is initially prepared by gelation and freeze-drying technique. The prepared CMC/MMT aerogels have a uniformly distributed pore structure, of which the compressive strength can reach 26.4 kPa when the MMT loading content is 40 wt%. When the MMT loading content is 40 wt%, the thermal conductivity of the PEG/CMC/40MMT CPCM can reach up to 0.78 W/m·K, which is 225 % higher than that of pure PEG. In particular, the rigid CMC/MMT composite aerogel is conducive to the storage of PEG, obtaining a maximum loading percentage of 96.8 %, phase change enthalpy of 179.2 J/g, and high enthalpy efficiency of 98.6 % for CMC/40MMT aerogel. The rigid supporting matrix and adsorption capacity of the CMC/MMT framework meliorate the shape stability and cyclic stability during the phase transition, which can also cool the surface temperature of a simulated central processing unit (CPU) from 90 °C to 54.7 °C. In summary, the as-prepared novel PEG/CMC/40MMT CPCM offers a novel strategy for thermal management of next-generation electronic devices.

Prediction of frictional behaviour through regression equations: A statistical modelling approach validated with machine learning

Friction in machinery and transportation has played a significant energy challenge, with the reducing friction and wear can improve the performance of engines, motors and vehicles.Therefore, this study involves fabrication, characterization, mechanical and tribological analysis of metal matrix composites (MMCs). Further, this study has developed of a statistical model to predict the frictional behaviour of Zinc-Aluminium in-situ composites reinforced with Zirconium diboride (ZrB2) particles. The alloy and composite were fabricated using liquid metallurgy, resulting in altered physical and morphological properties. Reinforcement with ZrB2 led to significant improvements in mechanical and tribological properties, resulting in a notably low coefficient of friction (COF) with lubrication, even under higher loads, signifying reduced energy losses. Response Surface Methodology (RSM) using Design Expert 13 software was used to analyze the relation between input parameters which included applied normal load, sliding distance, and ZrB2 percentage and output parameter (COF). A quadratic model was recommended as the best fit for the present material system and a regression equation was developed which predicts the frictional behaviour with more than 94% accuracy at given input variables. Moreover, ANOVA highlighted load as the primary influencer on COF characteristics. An Artificial Neural Network (ANN) in PYTHON validated RSM-recommended optimized COF parameters, enabling reliable COF predictions. A comparison of experimental and statistical outcomes from RSM and ANN confirms the model's strength in anticipating the tribological traits of alloys and composites.

Engineered Carbon Supports for Heavy-Duty Fuel Cell Vehicle Applications

Proton Exchange Membrane (PEM) fuel cells are a suitable electrochemical power source for heavy duty vehicle (HDV) applications due to their high performance, efficiency, and durability. The cathode of the fuel cell uses a higher geometric loading of platinum (~0.2 to 0.4 mgPt/cm2) for the electrocatalysis of the kinetically sluggish Oxygen Reduction Reaction (ORR), which requires higher weight percent loading of the metal (~50%) on the carbon support to decrease the catalyst layer thickness and hence, the reactant transport losses. Conventional supports for platinum catalysts, such as the KetjenBlackTM type high surface area carbon (HSC), feature limited mesopore area for the dispersion of Pt nanoparticles leading to increased aggregation and poor durability. Here, we show a new class of carbon materials developed by Pajarito Powder known as the Engineered Catalyst Support (ECS) with higher mesopore fraction for the dispersion of higher weight percentage of Pt nanoparticles. ECS materials can disperse up to 50% Pt by weight of the catalyst, thereby enabling lower catalyst layer thickness with higher performance retained after durability test. ECS materials are tunable in terms of their mesopore structure, graphitization levels and the use of metal-based additives as dopants on the carbon support to anchor catalyst nanoparticles. A comprehensive set of physico-chemical and electrochemical studies in membrane electrode assembly (MEA) are reported to understand the performance and durability of Pt/ECS catalysts. Acknowledgements: This work is partially supported by U.S Department of Energy, Hydrogen and Fuel Cell Technologies Office under grant DE-EE0008821 and DE-EE0010749.

(Invited) Independent Control of Visible and NIR Transmission through Electrochromic Windows with Green Solid Electrolyte

Energy efficiency in glass buildings is pivotal for achieving sustainable energy. Energy consumption is crucial in areas with diverse climatic conditions, including tropical and cold regions. In these environments, there is a notable demand for electricity due to the necessity of conditioning and heating systems to maintain resident comfort. Therefore, residents can address high energy consumption in buildings by regulating visible light and heat transmission through electrochromic windows. These windows modify their optical properties through adjustments in applied voltage. This work discussed the development of key components of electrochromic windows, including the electrochromic layer, ion-conductive layer, and electrolyte. The outstanding optical modulation of the electrochromic layer was achieved by coating a WO3 film onto NiO film. The presentation covered the synthesis of an ion-conductive layer with a reduced band gap, a high level of oxygen vacancy, and a reduction of resistance achieved through optimization of preparation parameters, such as annealing temperature and percentage loading of Cu. The architectural configuration comprised a bi-layer film containing WO3 coated on NiO as the electrochromic layer and a 5%Cu-doped NiO layer as the ion-conductive layer, with LiClO4 as the electrolyte. This configuration achieved a quadlet dual-band functionality, providing clear, cool, dark, and warm modes for resident comfort. In the clear mode, with no bias voltage applied, the window transmitted visible (630nm) and near-infrared light (930nm) at approximately 79.03% and 79.33%, respectively. The cool mode, regulated by a bias voltage of -2.5V, reduced NIR transmission to 41% while maintaining visible light transmission at 74%. The dark mode, with a bias voltage of -3V, blocked visible and NIR light to 0.09% and 0.02%, respectively. These phenomena resulted from the change of optical properties in the electrochromic layer. Conversely, the ion-conductive layer enabled the warm mode with a 2V bias, reducing visible light transmission to 50.31% while maintaining overall window transparency at 69.86%. Furthermore, the electrochromic window demonstrated excellent cycle stability, sustaining functionality up to 30,000 cycles while maintaining an optical modulation of 95% compared with the first cycle.Additionally, abundant silk waste from textile industries was transformed into a green solid electrolyte used in assembling electrochromic windows. An optimal configuration was found with a 10-micron thickness and 14.5 wt% of LiClO4 in the solid electrolyte, resulting in an excellent electrochromic window. In clear mode, the assembled window achieved a transmission of 74.67% in both visible and near-infrared regions. In the dark mode, the optical modulation difference (630 nm and 930 nm) between a solid electrolyte-assembled electrochromic window and a liquid electrolyte-assembled electrochromic window was less than 10%. Conversely, in cool mode, the solid electrolyte-assembled electrochromic window exhibited optical modulations of 75% and 39% at wavelengths of 630 nm and 930 nm, respectively, compared to a liquid electrolyte-assembled electrochromic window. Additionally, in warm mode, the optical modulation of the solid electrolyte-assembled electrochromic window at 630 nm and 930 nm was 60% and 91%, respectively, compared to that of a liquid electrolyte-assembled electrochromic window. Implementing these electrochromic windows for residential comfort can cause a decrease in electricity demand, which is currently the main issue of carbon dioxide emission from the conventional combustion of fossil fuels.

Superior EMI shielding behavior of multi-layer structure of PVDF based laminated nanocomposite material by controlling the size and distribution of W-type hexaferrite magnetic nanofillers therein

The effects of size and distribution of magnetic filler materials with different loading percentages inside PVDF matrix having mono-layer and multi-layer structures for the modulation of EMI shielding behavior are discussed in the present report. W-type hexaferrites are prepared using the sol-gel method, followed by the manually mortared and ball-milled techniques and embedded inside the PVDF matrix separately. Phase analysis and morphological studies are performed and discussed herein to understand the effect of ball mill technique, over the manually mortared process of W-type hexaferrites. Magnetic and dielectric studies are performed and the influence of the ball mill technique on magnetic and dielectric behavior of nanofillers as well as nanocomposite systems are discussed. Various physical properties of the nanocomposite films are performed within the range of 8-12 GHz. Significant modulations of complex permeability and the complex permittivity with size, distribution and loading percentage of the W-type hexaferrite inside PVDF matrix are found and the effect of impedance matching on EMI shielding behavior are also discussed. EMI shielding behavior of the resultant W-type hexaferrite-PVDF films in the 8-12 GHz frequency region shows the modulations of their absorption and/or reflection effectiveness due to the variation of the size, distribution and loading percentage of magnetic filler materials inside PVDF matrix. Both mono-layer and multi-layer structures of W-type hexaferrite-PVDF films are considered and the effect of thickness on the various parts of EMI shielding behavior is also reported.

Response Surface Optimization of Vibration Level in Diesel Engine with Biodiesel Usage: A Performance Enhancement Study

In this study, a single-cylinder direct-injection (DI) diesel engine was fueled by biodiesel. The Palm Oil Methyl Ester (POME), blended in amounts up to 20%, is tested at various engine speeds and loads to measure vibration level. Then, mathematical modeling was developed to relate the engine vibration level's responses to variables, including engine speed, load, and biodiesel blending percentage. Finally, all the numerical factors were calibrated using the proposed models. The significance of all factors in this study was demonstrated by the second peak of the engine's vibration, which contains a wealth of information about the excitations. Modeling results had previously shown that the significance of factors could vary according to the corresponding peaks of vibration in the engine. Meanwhile, the adjusted R2 of the developed model for vibration responses were 0.98, 0.87, 0.76, and 0.79, respectively. Further, the optimization results highlighted that utilizing a B20 fuel blend—a mixture of 20% biodiesel and 80% diesel fuel by volume—run at 2160 rpm with no load condition produced the best solution with the highest desirability value to satisfy all the responses. In summary, the study's findings showed that optimization should be considered while developing a new policy for using biofuel in internal combustion engines.

Preparation of hemp‐based biocomposites and their potential industrial application

AbstractBiocomposites are an emerging field in plastic industry. The incorporation of agri‐food waste in conventional or biobased polymer matrices allows the industry to lessen its carbon footprint, while producing recyclable plastic products. In this work, hemp hurd, a byproduct of hemp fiber production process, was used as a filler to prepare novel compostable composites in two different loadings (22% and 32% w/w respectively). Waste hemp hurds were selected due to their abundance and the lack of derived high‐value products. Three different polymers were used, namely poly[(tetramethyleneadipate)‐co‐(tetramethyleneterephthalate)] (PBAT) and poly(tetramethylene succinate) (PBS) as compostable polymers and a polyethylene elastomer for comparison. The bare polymers and prepared blends were then characterized for their structure and morphology by XRD and FESEM, as well as for their wettability, thermal and mechanical properties (namely energy absorbed on impact and flexural modulus). Structural and morphological characterization unveiled the different interactions occurring between hemp and the polymer matrices, suggesting the major impact of the type of used polymer when compared with biomass loading percentages. Mechanical tests showed that both PBAT and PBS blends properties are comparable to those of the pure polymers (i.e., in the case of PBAT the flexural modulus of the pure polymer was 82.2 MPa while the hemp‐loaded blends stood at around 50 MPa, whereas all PBS polymers and blends were 220 MPa, with no statistical difference between samples). These biomaterials have also similar thermal properties with respect to the bare polymers, underlining the promising potential as sustainable alternative to pure polymers.Highlights Waste hemp hurds were used to load biodegradable polymers at different percentages. Hemp hurd‐based biomaterials with excellent properties were prepared. Polymer flexural behavior was maintained even after hemp addition. Polymer‐hemp interactions for each polymeric matrix were elucidated. Hemp substitutes up to 32% w/w of polymer without affecting its properties.

Behavior of Concrete Beam Encasing Castellated Steel Section with Different Opening Size

This research aims to investigate the behavior of castellated steel sections with varying hole sizes enclosed in a concrete beam. Should two different opening size types (depth 140mm and depth 280mm) be used? When we use two types of shear connectors with full and partial interaction, stud connections integrate the steel and concrete parts. This research demonstrates We examined five simply-supported composite beams under two-point loading conditions. We constructed four examples using castellated steel beams and produced one specimen using standard steel beams as a control. We examine the maximum load support capacity. Examined are the specimens of composite beams' deformations. Among the many characteristics assessed are the castellated beam size of the aperture and the whole and partial composite interactions. According to test results, the sample had a 140mm hexagonal hole. The sample experienced an increase in final load percentages of approximately 11.11%. Compared to the sample featuring a 280mm hexagonal opening size, the mid-deflection and horizontal displacement showed a significant increase. The figures indicate a final load of approximately 18.82% and 16.7%, respectively. Full interaction also revealed a higher ultimate load for the sample with the same aperture. When the sample was fitted with a 140mm hexagonal hole, the percentages increased by approximately 6%. Additionally, the percentage of deflection at midspan and the percentage of horizontal displacement decreased by approximately 16.7% and 26.8%, respectively, compared to the sample with a hexagonal opening size of 280 mm.

In vitro Analysis of XLAsp-P2 Peptide Loaded Cellulose Acetate Nanofiber for Wound Healing

Recently, nanofiber-based wound dressings are currently a viable strategy to expedite the healing of wounds by providing a suitable microenvironment for tissue growth with active ingredients. This research study subjects the development of electrospun cellulose acetate (CA) nanofibers loaded with the XLAsp-P2, an antimicrobial peptide (AMP) that holds great potential for enhanced wound healing as a therapeutic agent. The synthesized XLAsp-P2-loaded CA nanofibers were fabricated via three loading percentages, 0.1 %, 0.2 %, and 0.3 % w/w, and characterized and evaluated their antimicrobial potential with MTT assay and Agar overlay methods as an alternative strategy. FT-IR analysis confirmed the compatibility of the peptide loaded CA nanocomposite, showing distinct peaks corresponding to the constituent materials. Scanning electron microscopy (SEM) analysis was employed to characterize the morphology of electrospun peptide CA nanocomposites and illustrate the fiber's size at the nanoscale. The in vitro release study during the 24 hrs, 87 % of the peptide was released which was approximately 5.2 mg; which was closer matched to the square root model of Higuchi at room temperature. MTT assay presented sensitive results towards Gram-positive bacteria compared to Gram Negative bacteria; which corresponded to the inhibition zones of the Agar overlay method proving that Escherichia coli (ATCC 25922) 17.66 ± 0.38 mm and Pseudomonas aeruginosa (ATCC 27853) 17.44 ± 0.38 mm exhibited moderate susceptibility, while Staphylococcus aureus (ATCC 25923)19.89 ± 0.69 mm and Bacillus cereus (ATCC 11778) 23.00 ± 0.33 mm showed promising responses. Collectively, The study's findings indicate that the XLAsp-P2 incorporated CA mat possesses an opportunity to function as an efficient platform for delivering therapeutic peptides.

Anisotropy and lateral compressive strength of large-size cement-stabilized macadam for bulging deformation resistance: A numerical analysis

Large-size cement-stabilized macadam (LCSM) base effectively hinders bulging deformation in asphalt pavements. Under vibratory compaction, the embedded skeleton structure and anisotropy of large-size aggregates (LSA) impact the mechanical properties of LCSM mixes. To reveal the mesostructure and anisotropy of LSA and determine the optimal volume percentage of LSA in LCSM mixes against bulging deformation, this study first characterized the bulging deformation resistance of LCSM mixes using lateral compressive strength (LCS). Next, the evolution of coordination number (CN) and distributions of contact force and contact normal for LSAs at different volume percentages under dynamic cyclic loading were investigated using the discrete element method (DEM). In particular, the induced anisotropic behavior was explored. Then, indoor tests and numerical simulations were conducted to assess the mixes’ LCS and vertical compressive strength (VCS); additionally, the compressive damage characteristics were analyzed. The results indicate that increasing the volume percentage of LSA and dynamic cyclic loading enhanced the CN, strong contact force, and contact normal density. LSAs at varying volume percentages exhibited pronounced anisotropic characteristics before and after loading, and the anisotropy factor of the LSA dropped after loading at a volume percentage of 65 %. Furthermore, the mixes’ VCS values exceeded LCS ones at the same LSA volume percentage, and there was a consistent relationship between the LSA anisotropy and the VCS/LCS ratio, suggesting that the optimal LSA volume percentage in LCSM mixes ranged from 60 % to 65 %. Finally, as the LSA volume increased, the skeleton effect became more pronounced than the interface attenuation effect, leading to higher VCS and LCS values in the mixes, thus improving their resistance to bulging deformation.

Posture and vision: How different distances of viewing target affect postural stability and plantar pressure parameters in healthy population

BackgroundPostural stability is maintained by the Postural Control System (PCS), consisting of anatomical structures of Central Nervous System and peripheral receptors, interacting with each other, in order to keep whole-body balance by modulating the myofascial chains against gravity. The vision is one of the most important peripheral receptors for postural control. Previous studies analyzed the changes of body sway during viewing nearby (VNT) and distant (VDT) targets in healthy population without considering the feet adaptations related to the body weight distribution. Aim of this study was to investigate how different distances of viewing target affect the variability of postural stability and plantar pressure parameters in healthy subjects. Methods31 stabilometric and plantar pressure parameters were acquired in 20 young healthy subjects by baropodometry performed in bipedal standing during VNT and VDT (0.70 m and 3 m from the heels, respectively). Variability and statistical differences between VDT and VNT were implemented. ResultsResults showed the highest repeatability for plantar pressure parameters, a slightly high for CP speed and a lowest for CoPsa and Length Surface Function during both VNT and VDT. Moreover, a significant increase of load percentage on left-foot and right-Forefoot, of mean and maximum pressures on left-Forefoot, of CoPsa and CPspeed and a decrease of LSF were found during VDT. DiscussionThis study revealed how a greater distance of viewing target affects body-weight distribution and increases body oscillations. These findings highlighted the importance of visual target distance for the correct interpretation of postural stability and plantar pressure parameters, and the need to standardize target distance during stabilometric exam.

Development of a selective COX-2 inhibitor: from synthesis to enhanced efficacy via nano-formulation.

Non-steroidal anti-inflammatory drugs NSAIDs are widely used for managing various conditions including pain, inflammation, arthritis and many musculoskeletal disorders. NSAIDs exert their biological effects by inhibiting the cyclooxygenase (COX) enzyme, which has two main isoforms COX-1 and COX-2. The COX-2 isoform is believed to be directly related to inflammation. Based on structure-activity relationship (SAR) studies of known selective COX-2 inhibitors, our aim is to design and synthesize a novel series of 2-benzamido-N-(4-substituted phenyl)thiophene-3-carboxamide derivatives. These derivatives are intended to be selective COX-2 inhibitors through structural modification of diclofenac and celecoxib. The compound 2-benzamido-5-ethyl-N-(4-fluorophenyl)thiophene-3-carboxamide VIIa demonstrated selective COX-2 inhibition with an IC50 value of 0.29 μM and a selectivity index 67.24. This is compared to celecoxib, which has an IC50 value of 0.42 μM and a selectivity index 33.8. Molecular docking studies for compound VIIa displayed high binding affinity toward COX-2. Additionally, the suppression of protein denaturation with respect to albumin was performed as an indicative measure of the potential anti-inflammatory efficacy of the novel compounds. Compound VIIa showed potent anti-inflammatory activity with 93% inhibition and an IC50 value 0.54 μM. In comparison, celecoxib achieved 94% inhibition with an IC50 value 0.89 μM. Although molecule VIIa demonstrated significant in vitro anti-inflammatory activity, adhered to Lipinski's "five rules" (RO5) and exhibited promising drug-like properties, it showed indications of poor in vivo activity. This limitation is likely due to poor aqueous solubility, which impacts its bioavailability. This issue could be addressed by incorporating the drug in niosomal nanocarrier. Niosomes were prepared using the thin-film hydration technique. These niosomes exhibited a particle size of less than 200 nm, high entrapment efficiency, and an appropriate drug loading percentage. Transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) studies revealed that the niosomes were spherical and demonstrated compatibility of all of its components. The drug release study indicated that the pure drug had limited practicality for in vivo use. However, incorporating the drug into niosomes significantly improved its release profile, making it more suitable for practical use.

Enhancing Albendazole Delivery Using Mesoporous Santa Barbara Amorphous‐15: A Box‐Behnken Design Study

Over 70% of pharmaceutical compounds face the challenge of poor water solubility, which impacts on their bioavailability. This study focuses on the use of Santa Barbara Amorphous‐15 (SBA‐15) mesoporous silica material as carrier, which is synthesized and characterized to address this limitation. Albendazole (ABZ), an antiparasitic agent with low water solubility, serves as model drug. A Box‐Behnken design (BBD) is used to investigate the impact of immersion method loading factors (temperature: 25–50 °C, time: 24–72 h, and SBA‐15 amount: 83.2–252.0 mg) on drug loading percentage (DL%) and dissolution efficiency (DE%). The ABZ loading is confirmed by elemental analysis and Fourier transform infrared spectroscopy. Stability tests are performed, comparing drug dissolution profiles and X‐ray diffraction patterns immediately after loading and after 12 months of storage at 25 °C and 60% relative humidity (RH%). DL% varies between 18% and 36% (w/w), showing that the amount of SBA‐15 is the most significant factor on DL%. The lowest SBA‐15 amount yielded the highest DL%. Regarding DE%, all the design samples exhibit higher values than pure ABZ, with the amount of SBA‐15 being the primary influencing factor. Several samples from the BBD show high DE% (>70%) corresponding to high DL% values. After 12 months, most samples maintain similar dissolution profiles, demonstrating the good stability of the drug in the carrier over time. This study provides valuable insights into optimizing the loading process to enhance ABZ solubility and long‐term stability using mesoporous SBA‐15.