Types Of Suspensions Research Articles

Enhanced three-dimensional particle detection in microcirculation experiments with defocus particle tracking and ghost red blood cells

AbstractExperimental investigations on the motion of rigid particles in microcirculation environments are still scarce owing to the three-dimensional (3D) motion of the particles and to the particle image masking due to the presence of the red blood cells (RBCs). Despite the recent progress on the 3D tracking of rigid particles in RBC flows with defocus particle tracking (DPT) methods, the problem of particle image masking remains to be solved. Here, we propose, test, and evaluate the use hemoglobin-free RBCs, also known as ghost RBCs, as a replacement for normal RBCs in experiments with rigid particles in microcirculation environments. We performed DPT measurements of a pressure-driven flow of normal and ghost RBC suspensions seeded with rigid particles at three different flow rates. We show that the quasi-transparent appearance of ghost RBCs, as a result of the lack of hemoglobin, eliminates the RBC-induced masking of the defocused particle images and allows to achieve the particle matching standards found in cell-free experiments. In fact, ghost RBC suspensions enable the tracking of the rigid particles across the entire height of the microchannel, which was not possible in normal RBC flows. On a fluid dynamic level, we show that ghost RBC suspensions provide similar conditions to normal RBCs in terms of the velocity of the rigid particles and the rigid particles exhibit similar lateral dynamics in both types of cell suspensions. In essence, the findings from this work demonstrate that ghost RBCs are a well-suited replacement for normal RBCs in experiments aiming at deciphering the motion of rigid particles in microcirculation environments. Graphical abstract

Effect of catalyst and oxidant concentrations in a TEMPO oxidation system on the production of cellulose nanofibers.

In traditional TEMPO oxidation systems, the high cost of TEMPO catalysts has been a significant barrier to the industrialization of oxidized CNF. From an economic perspective, presenting the characteristics of various CNFs produced with the oxidation systems with reduced catalyst usage could facilitate the industrial application of CNF across a wide range of fields. In this study, it was demonstrated that reducing the amount of TEMPO catalyst used (from 0.1 to 0.05 mmol g-1) in a conventional oxidation system increased the carboxylate content by approximately 6.3%. Furthermore, the activation of hydroxyl amine TEMPO, which is generated after the oxidation reaction of cellulose, was enhanced by adjusting the dosage of the inexpensive oxidant NaClO, leading to a 20% improvement in carboxylate content. This suggests that controlling the amount of NaClO as an oxidant can be a key parameter in adjusting the dosage of TEMPO to achieve the targeted degree of surface substitution. Results from the dispersion stability, UV-transmittance, and morphological properties of TEMPO-oxidized CNF using microfluidizing treatment showed that high carboxylate content plays a crucial role in producing high-purity CNF suspensions, which are small, uniform, and free from microfibers. Additionally, by varying the number of mechanical treatments applied to the oxidized cellulose, various types of CNF suspensions with different mean widths were obtained. We expect that these findings offer meaningful insights to end-users seeking a breakthrough in the performance limitations of final applications using cellulose nanomaterials.

Journey of frontalis muscle advancement in severe blepharoptosis: Review of the techniques, modifications, and outcomes.

We aimed to review the degree of standardization of frontalis muscle (FM)-orbicularis muscle advancement techniques in the management of severe congenital blepharoptosis and also study the evidence which supports the procedure correcting blepharoptosis. The undisputed rationale of all types of brow suspension in the management of severe blepharoptosis is based on the concept that slings are the conventional way to simultaneously suspend a ptotic eyelid and transmit the contractile action of the FM to the tarsal plate. Traditionally, frontalis suspension using sling has been used to treat patients with severe congenital blepharoptosis with poor levator function; however, postoperative lagophthalmos, forehead scarring, and recurrence remain major concerns. Since the early 80s, a significant number of consecutive articles have suggested that the eyelid can be effectively suspended by directly suturing FM to the tarsal plate. This review article intends to evaluate the level of standardization of FM advancement techniques in the management of severe blepharoptosis. 'In addition, to determine if the procedure should be performed in a standard manner, and is there enough evidence available to recommend FM advancement as a useful surgical technique.

Magnetodielectric and Rheological Effects in Magnetorheological Suspensions Based on Lard, Gelatin and Carbonyl Iron Microparticles.

This study aims to develop low-cost, eco-friendly, and circular economy-compliant composite materials by creating three types of magnetorheological suspensions (MRSs) utilizing lard, carbonyl iron (CI) microparticles, and varying quantities of gelatin particles (GP). These MRSs serve as dielectric materials in cylindrical cells used to fabricate electric capacitors. The equivalent electrical capacitance (C) of these capacitors is measured under different magnetic flux densities (B≤160 mT) superimposed on a medium-frequency electric field (f = 1 kHz) over a period of 120 s. The results indicate that at high values of B, increasing the GP content to 20 vol.% decreases the capacitance C up to about one order of magnitude compared to MRS without GP. From the measured data, the average values of capacitance Cm are derived, enabling the calculation of relative dielectric permittivities (ϵr') and the dynamic viscosities (η) of the MRSs. It is demonstrated that ϵr' and η can be adjusted by modifying the MRS composition and fine-tuned through the magnetic flux density B. A theoretical model based on the theory of dipolar approximations is used to show that ϵr', η, and the magnetodielectric effect can be coarsely adjusted through the composition of MRSs and finely adjusted through the values B of the magnetic flux density. The ability to fine-tune these properties highlights the versatility of these materials, making them suitable for applications in various industries, including electronics, automotive, and aerospace.

Integration of bio-inspired limb-like structure damping into motor suspension of high-speed trains to enhance bogie hunting stability

Hunting stability is an important performance criterion in railway vehicles. This study proposes an incorporation of a bio-inspired limb-like structure (LLS)-based nonlinear damping into the motor suspension system for traction units to improve the nonlinear critical speed and hunting stability of high-speed trains (HSTs). Initially, a vibration transmission analysis is conducted on a HST vehicle and a metro vehicle that suffered from hunting motion to explore the effect of different motor suspension systems from on-track tests. Subsequently, a simplified lateral dynamics model of an HST bogie is established to investigate the influence of the motor suspension on the bogie hunting behavior. The bifurcation analysis is applied to optimize the motor suspension parameters for high critical speed. Then, the nonlinear damping of the bio-inspired LLS, which has a positive correlation with the relative displacement, can further improve the modal damping of hunting motion and nonlinear critical speed compared with the linear motor suspension system. Furthermore, a comprehensive numerical model of a high-speed train, considering all nonlinearities, is established to investigate the influence of different types of motor suspension. The simulation results are well consistent with the theoretical analysis. The benefits of employing nonlinear damping of the bio-inspired LLS into the motor suspension of HSTs to enhance bogie hunting stability are thoroughly validated.

Wearable, Biocompatible, and Dual-Emission Ocular Multisensor Patch for Continuous Profiling of Fluoroquinolone Antibiotics in Tears.

The abuse or misuse of antibiotics in clinical and agricultural settings severely endangers human health and ecosystems, which has raised profound concerns for public health worldwide. Trace detection and reliable discrimination of commonly used fluoroquinolone (FQ) antibiotics and their analogues have consequently become urgent to guide the rational use of antibiotic medicines and deliver efficient treatments for associated diseases. Herein, we report a wearable eye patch integrated with a quadruplex nanosensor chip for noninvasive detection and discrimination of primary FQ antibiotics in tears during routine eyedrop treatment. A set of dual-mode fluorescent nanoprobes of red- or green-emitting CdTe quantum dots integrated with lanthanide ions and a sensitizer, adenosine monophosphate, were constructed to provide an enhanced fluorescence up to 45-fold and nanomolar sensitivity toward major FQs owing to the aggregation-regulated antenna effect. The aggregation-driven, CdTe-Ln(III)-based microfluidic sensor chip is highly specific to FQ antibiotics against other non-FQ counterparts or biomolecular interfering species and is able to accurately discriminate nine types of FQ or non-FQ eyedrop suspensions using linear discriminant analysis. The prototyped wearable sensing detector has proven to be biocompatible and nontoxic to human tissues, which integrates the entire optical imaging modules into a miniaturized, smartphone-based platform for field use and reduces the overall assay time to ∼5 min. The practicability of the wearable eye patch was demonstrated through accurate quantification of antibiotics in a bactericidal event and the continuous profiling of FQ residues in tears after using a typical prescription antibiotic eyedrop. This technology provides a useful supplement to the toolbox for on-site and real-time examination and regulation of inappropriate daily drug use that might potentially lead to long-term antibiotic abuse and has great implications in advancing personal healthcare techniques for the regulation of daily medication therapy.

A Review on Controlling Methods for Semi-Active Suspension Systems

Abstract: In recent years the need of vehicle safety and ride comfort has led to develop effective modeling and control methods of suspension system. There are many methods already found to develop and control this kind of suspension systems. Mainly there are three types ofsuspension systems, Active, Semi-Active and Passive suspensions. This research paper presents a comprehensive review of controlling methods employed in semi-active suspension systems, a critical component in modern vehicle dynamics. Out of these three, semi-active suspension has the ability to adapt with the technical changes in the system model. In this paper some of the control methods for the semi-active suspension system have been discussed and a quick review is done on their way of operation. Moreover, the paper addresses recent advancements in semi-active suspension control, such as the integration of machine learning and optimization techniques.

Calculation Model for Evaluating Suspensions during Maneuvers of a 4WD Vehicle with a 6x6 Wheels

The article describes the purpose, scope, main parameters of the flowchart of the procedure used to calculate control devices when comparing vehicle suspension structures with a 6x6 wheel arrangement. Methods for comparing suspensions during maneuvers are described. A description of the cab suspension system, a block diagram of the simulation program is presented. The visualization of the process of rebuilding the studied model of a 6*6 vehicle with two different types of front suspension is shown. An estimate of the load on the front and rear axles during the rebuilding for a period of time t = 5 s, their energy output and inertia is given. The distribution of the load along the axes of the investigated 6*6 vehicle model is presented when rebuilding with the front suspension of the first and second types. The coordinates of the base points of the front axle allow you to evaluate the numerical values for specific coordinates at a given point in time.

School Leadership, Race, and School Discipline: Examining the Relationship Between School Leader-Student Racial Congruence and the Likelihood of Exclusionary Discipline

Racial disparities in disciplinary outcomes are a salient educational policy and equity issue. Most of the research on school discipline focuses on teachers rather than school leaders and prior studies have largely examined principals’ attitudes. This study uses data from a mid-sized urban district to examine how student-school leader race interactions influence the likelihood of receiving suspensions conditional on receiving an infraction, with specific focus on Black, Latinx and White students and both principals and assistant principals (APs). The results indicate that the prevalence of exclusionary discipline is similar for schools with Black and White principals, but slightly higher in schools with White principals (this is the case for both elementary and high schools, but not middle schools). Black-White discipline disparities are higher in schools with White principals and APs, compared to schools with Black principals and APs. But there are no clear patterns for Latinx-White disparities. The probability of students receiving suspensions varies substantially across infraction type, principal race, AP race, and schooling level. The findings illustrate the nuances between the overall and discriminatory use of suspensions and highlight the need for closer attention to the types of suspensions and infractions. States and districts should also invest in initiatives that diversify school leadership given the importance of diversity for students’ disciplinary experiences.

Investigation of Ionic Polymers' Stabilizing and Flocculating Properties in Dispersed Activated Carbons Systems.

Activated carbons obtained via the thermochemical treatment of lemon balm and mint herbs were applied for ionic polymers adsorption, which directly affects the stability of these types of aqueous suspensions. The examined carbonaceous materials were characterized by well-developed specific surface area (approximately 1000 m2/g) and mesoporous structure. The adsorbed amounts of anionic poly(acrylic acid) and cationic polyethyleneimine from one-component solutions reached significant levels, but the efficiency of adsorption of these compounds from binary solutions slightly decreased. Moreover, the ionic polymers showed stabilizing properties towards the activated carbons suspensions. For both adsorbents, the most stable suspensions were systems containing both types of polymeric macromolecules with different ionic characters. This was due to the occurrence of electrosteric and depletion stabilization mechanisms. Furthermore, the zeta potential and size of particle aggregates were also influenced by the presence of polymers in the aqueous suspensions of activated carbons.

Measurements of rotational stiffness for precast concrete girder transport vehicles, part 2

This paper presents field measurements of the rotational stiffness of three transport vehicles equipped with different types of suspensions: leaf, combined air and leaf, and hydraulic suspensions. The rotational stiffness was determined by measuring the tilts of the vehicles when a girder or known weights were placed on them at various eccentricities. One of the tested vehicles, which featured transversely expandable wheel spacings varying from 6 to 18 ft (1.8 to 5.5 m), exhibited an increase in rotational stiffness from 78,181 to 134,584 kip-in./radian (8833 to 15,206 kN-m/radian). This paper summarizes the rotational stiffness for all the vehicles tested by the authors. The field measurements conducted have enriched the existing database on vehicle rotational stiffness in the United States.

Design and Finite Element Analysis of an Automatic Electromechanical Overload Detecting System for Trucks

This paper presents a simple design, low‐cost, electromechanical overloading system, which is easy to use and install and suitable for all types of truck chassis and suspension. This design can detect an overload, signal the driver, and also interrupt ignition when the truck is overloaded. The system was modelled using CAD software, and FEA was performed on the spring component to verify analytical solutions. Components of the overload detection system include a load carrying springs, an electrical relay, ignition system, an LED for signaling overload, and an electrical circuit. Results showed that, for a 3‐axle trucks, the allowable pay load was 15.125 tonnes, and each spring in the design supports a minimum weight of 74.183 kN. A spring index of 4.009 was achieved in line with safe design conforming to 4 ≤ C ≤ 12 with a spring rate of 1464305.5 N/m. The spring displacement needed to actuate the overloading system was 51 mm. FEA which was performed validated analytical solutions in that the induced von Mises stress which was 69.92 MPa was below the yield strength of the material (200 MPa) and the factor of safety obtained was 1.24 signifying safe design. The designed electromechanical system is capable of detecting an overloadand also interrupting the truck ignition. Installation can be installed on new trucks or by retrofitting onto old trucks.

Umbilical cord-derived mesenchymal stem cell sheets transplanted subcutaneously enhance cell retention and survival more than dissociated stem cell injections

BackgroundHuman umbilical cord-derived mesenchymal stem cell (hUC-MSC) sheets have recently attracted attention as an alternative approach to injected cell suspensions for stem cell therapy. However, cell engraftment and cytokine expression levels between hUC-MSC sheets and their cell suspensions in vivo have not yet been compared. This study compares hUC-MSC in vivo engraftment efficacy and cytokine expression for both hUC-MSC sheets and cell suspensions.MethodshUC-MSC sheets were prepared using temperature-responsive cell culture; two types of hUC-MSC suspensions were prepared, either by enzymatic treatment (trypsin) or by enzyme-free temperature reduction using temperature-responsive cell cultureware. hUC-MSC sheets and suspensions were transplanted subcutaneously into ICR mice through subcutaneous surgical placement and intravenous injection, respectively. hUC-MSC sheet engraftment after subcutaneous surgical transplantation was investigated by in vivo imaging while intravenously injected cell suspensions were analyzing using in vitro organ imaging. Cytokine levels in both transplant site tissues and blood were quantified by enzyme-linked immunosorbent assay.ResultsAfter subcutaneous transplant, hUC-MSC sheets exhibited longer engraftment duration than hUC-MSC suspensions. This was attributed to extracellular matrix (ECM) and cell–cell junctions retained in sheets but enzymatically altered in suspensions. hUC-MSC suspensions harvested using enzyme-free temperature reduction exhibited relatively long engraftment duration after intravenous injection compared to suspensions prepared using trypsin, as enzyme-free harvest preserved cellular ECM. High HGF and TGF-β1 levels were observed in sheet-transplanted sites compared to hUC-MSC suspension sites. However, no differences in human cytokine levels in murine blood were detected, indicating that hUC-MSC sheets might exert local paracrine rather than endocrine effects.ConclusionshUC-MSC sheet transplantation could be a more effective cell therapeutic approach due to enhanced engraftment and secretion of therapeutic cytokines over injected hUC-MSC suspensions.

The protective nature of the institution of suspending a policeman in official duties

The aim of the work is to verify the hypothesis that the institution of suspending a police officer from official duties is a very important element of administrative and legal protection of all Police officers in Poland. The service relationship under which a Police officer performs activities entrusted to him by the state is an administrative legal relationship. Performing official duties resulting from the content of the administrative and legal relationship between a police officer and the state is the duty of every officer. However, the Police Act provides for the institution of suspending a policeman from official duties, which makes it possible to prohibit a policeman from performing official duties for a specified period of time. The paper discusses two types of suspension in official duties, i.e. obligatory and optional suspension. Attention was also paid to the effects of suspension in official duties on the policeman's service relationship. The dual nature of the institution in question was emphasized. This institution serves to quickly deprive a policeman of the opportunity to perform his official duties until the criminal or disciplinary charges against him are clarified. First of all, however, it has a protective nature for the officer, as it allows him to remain in service despite such allegations being made against him

TESTING THE BREAKING FORCE OF ROCKET PROJECTILE SUSPENSIONS TO PARACHUTE

Design of a recovering system is one of crucial tasks in development work over the rocket projectiles. Properly designed recovering system secures the recovery of testing projectile after firing in undamaged state, what significantly reduces the time and cost of conducted tests. A parachute with its fixation to a projectile which has to be recovered are key components of the recovering system providing its proper operation. Due to the presence of high values of forces acting at the parachute opening and deacceleration of the object the proper selection of suspension is important factor for its efficient recovery. The paper present tests of breaking force for various types of suspensions connecting the object and the parachute.

The Evolution of Vehicle Pneumatic Vibration Isolation: A Systematic Review

Whole-body vibration (WBV) is a significant concern for vehicle users as it can negatively impact their health and comfort. As such, effective vibration isolation is critical in vehicle suspension design. The ability of a vehicle suspension to isolate vibrations depends primarily on the suspension design and the type of springs used. One type of spring that has proven advantageous for vibration isolation is the air spring. Air springs can vary frequencies and adjust their stiffness in response to different loading conditions, making them ideal for meeting both suspension load-carrying and occupants’ comfort requirements. Pneumatic (air) suspension has been in use in the automotive industry for several decades and has undergone significant advancements during this period. This paper presents a systematic review of pneumatic suspension since its inception. The review highlights different air spring modeling techniques, types of pneumatic suspension, and control methods. The study also discusses the functional flexibility of pneumatic suspension, its ability to offer a wide range of control options to drivers, and its broad application in almost all ranges of vehicles, including chassis, cabin, and seat suspension systems. In addition, this paper presents a summary of the pros and cons of pneumatic suspension and suggests future research directions. The advantages of pneumatic suspension include effective vibration isolation, improved ride comfort, and the ability to adjust suspension stiffness and ride height. On the other hand, the disadvantages include higher cost and complexity compared to other types of suspension. Overall, the findings of this review demonstrate that pneumatic suspension is a viable solution for vehicle suspension design, particularly in situations where vibration isolation and ride comfort are critical.

Response of Cucumber Pants to the Addition of Animal Waste and Dry Yeast Suspension

A factorial experiment was carried out during the year 2021 in one of the villages in the Abu Ghraib district – Baghdad, to evaluate the effect of adding animal waste and dry bread yeast suspension on some vegetative growth characteristics of cucumber plants (Hadeel hybrid) grown under a protected environment. Three types of animal wastes (cattle, sheep and poultry) and dry bread yeast suspension were selected and the control treatment without adding any organic waste. The results indicated that poultry manure showed the best effects in the studied traits, which included leaf area ) of 31.69 cm2 (, dry weight of shoot )40.0 g(, number of leaves )32.73 leaf plant-1 ), stem diameter (11.48 mm), plant length (224.3 cm) and number of nodes 33.73 node plant-1 ).On the other hand, adding dry yeast suspension to plants improved in all studies of vegetative growth characteristics compared to the control treatment. Keywords: Cucumber, fertilize, organic manure, biofertilizer, vegetative growth.

Study of the rheological properties of clayey suspensions: an interest in the field of landfills

In the landfill bottom liners design process, geotechnical tests of long duration time are often conducted to ensure the presence of reactive clays and to assess their hydromechanical properties. This study aims to show the interest of the rheometry of clayey suspensions as an alternative tool for identifying clays and determining the shear strength of bottom liners. An experimental protocol, using a six-speed rotary viscometer, was first implemented on bentonite suspensions on the one hand and kaolinite suspensions on the other. The results show that to have similar shear strengths (between 1.0 and 25.4 Pa), the concentration ranges used for these two types of suspensions must be totally different: between 600 to 1200 g/L for kaolinite and 30 to 90 g/L for bentonite, confirming the usefulness of rheometry as a tool for identifying clays. Furthermore, results from rheometry tests also show an increase in the shear stress of kaolinite suspensions when there are made with leachate; such results are in agreement with geotechnical shear tests conducted on compacted samples. This study is of practical use for environmental geotechnics professionals because it offers an alternative to traditional geotechnical tests.

酸化スズナノ粒子サスペンションを用いたマイクロスケールのパターニング

This review focuses on our results on the fabrication of large-area patterning of tin oxide suspensions by the “micromolding in capillary” (MIMIC) method, one of the soft lithography techniques. Usually, suspensions with high solid loadings have been experimented, but since the filling mechanism of the MIMIC method is capillary action, the viscosity increases during the process, resulting in a smaller patterning area. We have confirmed that a low solids ethanol suspension of tin oxide nanoparticle can be used to achieve large-area patterning, forming a stripe pattern with a thickness of almost 1/3 the depth of the mold channel, resulting in a dense structure. Confirming the patterning mechanism, we found that controlling solvent evaporation during the process was very effective. It is expected that this MIMIC process for low solids loading suspensions of nanoparticles will be widely deployed for other types of ceramic suspensions.

Experimental Study on Electrical Conductivity of Several [C4mim][BF4] Ionic-Liquid-Based Nanocolloids.

Nanocolloids are receiving considerable attention in regard to their properties and future applications, especially as heat transfer fluids and phase change materials for energy storage. Additionally, studies on ionic liquids and ionic-liquid-based nanocolloids are at the forefront of research preoccupations. This study aims to shed light on applications of nanocolloids based on [C4mim][BF4] ionic liquid, giving insight into the electrical conductivity of [C4mim][BF4] ionic liquid, as well as three types of nanoparticles suspended in this particular ionic liquid, namely Al2O3 (alumina), ZnO (zinc oxide) and MWCNT (multi-walled carbon nanotubes). In this experimental research, three types of suspensions were carefully prepared and the electrical conductivity was measured both at ambient temperature and during heating. The results are discussed in the context of the state of the art. The electrical conductivity variation with temperature was found to be linear, and nanoparticle loading significantly influenced the electrical conductivity of the suspensions. A complex analysis in terms of temperature and nanoparticle type and loading was performed. In conclusion, the electrical properties are relevant for many applications and further experimental work needs to be devoted to their study.