Extrusion Type Research Articles

Early and Late Surgery-Free Rates of Conservative Management Strategy for Thrombosed Type A Acute Aortic Dissection and Acute Intramural Hematoma.

Background: We have employed a conservative management approach, including intensive control of both blood pressure and heart rate, in patients with aortic intramural hematoma (AIMH) and retrograde thrombosed type A acute aortic dissection (RT-TAAAD), sharing common clinical and imaging characteristics. Methods: To evaluate the outcomes of our conservative management approach, we retrospectively reviewed the clinical records of 98 patients diagnosed with AIMH or RT-TAAAD from January 2008 to March 2023. A conservative management approach was applied, except for those patients with an aortic diameter ≥ 55 mm, false lumen expansion, or cardiac tamponade, who underwent emergency aortic repair. Results: Besides 2 patients, who declined surgery and subsequently died from aortic rupture, 18 patients underwent urgent aortic surgery, while 78 did not. Multivariable logistic regression analysis identified the extrusion type of ulcer-like projections (ULPs) on admission and a maximum aortic diameter ≥ 45 mm on Day 1 as risk factors for acute aortic surgery. Among the 78 patients who were discharged, 9 (12%) underwent aortic surgery, while 69 (88%) did not, with a median follow-up of 44 months. The overall actuarial aortic surgery-free rates were 78% at 1 year and 72% at 5 years, respectively. A Cox proportional hazards analysis identified ULPs and an aortic diameter ≥ 45 mm at discharge as risk factors for late aortic surgery. Conclusions: The early and late outcomes of our conservative strategy for AIMH and RT-TAAAD demonstrate favorable surgery-free rates. The extrusion type of ULPs on admission and an aortic diameter ≥ 45 mm on Day 1 are predictors of acute aortic surgery, while ULPs and an aortic diameter ≥ 45 mm at discharge are predictors of late surgery.

Fabrication of functional surfaces using layer height method in material extrusion type 3D printing

Various layer stacking methods have been employed in material extrusion type three-dimensional (3D) printing to utilize their potential for addressing the inherent technological limitation of reduced surface quality due to layer stacking. The process involved fabricating a material extrusion type 3D printed mold using diverse layer height-changing methods and subsequently replicating the surface pattern with the polymer. This approach is called the layer height method (LHM) and comprises three distinct variations. The first method involves altering the height of the individual layers to generate diverse surface morphologies and, consequently, varying the range of water contact angles. The second method focuses on rapid layer height changes to facilitate liquid deposition within regions with low contact angles. Finally, a layer height gradient was systematically established within the mold, resulting in a wettability gradient surface capable of controlling the movement of water droplets across the surface. The performance of these functional surfaces was successfully validated using various experimental methods. This study introduces a manufacturing technique based on changing layer heights within the framework of material extrusion-type 3D printing technology. A wide range of intricate and diverse functional surfaces can be produced by extending the manufacturing method proposed in this study to 3D printing technologies beyond the scope of material extrusion type 3D printing.

Feedrate-preserved motion planning for five-axis directed energy deposition of freeform metal parts

Laser-powder DED (LP-DED) has been investigated extensively for the rapid prototype of complex and customized metallic parts and in-situ repairing tasks. However, unlike the material extrusion type which allows a relatively large overhang angle, the conventional 2.5-axis LP-DED faces a severe overhang issue that deteriorates the printing stability and quality. While five-axis LP-DED is able to effectively resolve the overhang problem, it however introduces new kinematic issues and limited nozzle orientation range due to physical restrictions of DED. The existing computer numerical control systems are mainly designed for machining, where the above issues can be mostly solved by feedrate scheduling, which, however, is not applicable for LP-DED processes, as the feedrate must be preserved as programmed lest deposition height would be altered since in most cases it is not practical to vary the powder flow rate in real-time. In this paper, a feedrate-preserved motion planning method is proposed to optimize the rotational angles of the machine tool in the machine coordinate system (MCS) under the constraints of MCS and workpiece coordinate system (WCS). Given a five-axis DED path as well as its accompanying initial nozzle orientation in WCS, we first map them via inverse kinematics to MCS, which is represented by a cylindrical coordinate system. Then, the motion path in the cylindrical coordinate system is optimized to avoid the singularity. Finally, the physical constraint of nozzle orientation in WCS is introduced into the time-weighted constrained Laplacian smoothing in MCS with the axial speed limits upheld. The experimental results confirm that the actual feedrate is successfully preserved as the theoretical one under the constraints of the axial kinematic limits, while the singularity is avoided.

Hot Melt Extrusion Technique for Developing Pharmaceutical Co-crystals: A Review

Background: In the era of pharmaceutical research and development, the most challenging aspect is to enhance the physicochemical properties of drugs. Hot Melt Extrusion (HME) is a solvent-free, one-step, continuous, scalable, and industrially feasible method for developing pharmaceutical co-crystals. Co-crystallization, as a technique, has gained significant attention for its potential to modify various physicochemical properties of drugs like solubility, stability, compressibility, permeability, taste masking, and therapeutic efficacy Methods: We determine the characteristic features of HME and explore published literature using the keywords, HME, co-crystals, and PAT, in databases, such as PubMed, Google Scholar, ScienceDirect, and Research Gate. Result: The present review embarks on a detailed journey through the multifaceted domain of HME and its pivotal role in co-crystal development. The process parameters, such as temperature, extruder type, screw configuration, screw speed, and feed rate, are involved in determining the characteristics of the co-crystals produced. Additionally, the review explores the role of materials, including Active Pharmaceutical Ingredients (APIs), plasticizers, polymers, and other pharmaceutical aids, underlining their impact on co-crystal development. The existing literature on HME and its application for pharmaceutical co-crystal production is comprehensively surveyed. Conclusion: The review highlights the utility of Process Analytical Technology (PAT) in real-time process control. The role of HME in the future of pharmaceutical co-crystal development is discussed, making this review essential for researchers and industry professionals alike.

Effects of single and twin thermal screw extrusion on protein quality of grain-free pet foods formulated with predominantly animal- or plant-based protein ingredients

With the diversification of the pet food industry and increasing market demand, the inclusion of plant protein in companion animal diets has become of interest. Pulses, commonly seen in grain-free diets, are high in protein and could serve as an alternative source of animal-based protein. There has been research on the ingredient about nutrient profiles and effects on canine health. However, little is known about the amino acid availability when pulses are incorporated into diets. In addition, there is lacking in knowledge about the effect of extrusion processing on protein quality and the possible interaction between processing and ingredients. Therefore, the study was conducted to determine the effect of extrusion and pulses on amino acid digestibility and protein quality. Eight grain-free diet formulations were designed: chicken byproduct meal diet (CON), chicken slurry diet (SLR), chicken slurry + yellow pea diet (SLR+YP), yellow pea diet (YP), green lentil diet (GL), garbanzo bean diet (GB), chicken slurry + taurine diet (SLR+TAU), and chicken slurry + yellow pea + taurine diet (SLR+YP+TAU). Two types of extruders were used: single screw and twin screw extruder. Diet samples were taken at 3 processing time points: raw ingredients, at the end of the preconditioner, and at the end of the extruder. The resulting 48 diet samples were analyzed for chemical composition and fed to cecectomized roosters (n=4/treatment) to determine standardized ileal amino acid digestibility and Digestible Indispensable Amino Acid Score (DIAAS)-like values. Even though the diets were mostly similar in chemical composition, methionine content was lower in diets containing yellow pea and green lentil. Extrusion processing did not have negative effect on natural or synthetic taurine in the diets. Preconditioning and extrusion also increased amino acid digestibility and DIAAS-like values in most diets, as processed diets could be considered well-digested and of good protein quality. According to reference protein sources, tryptophan and methionine were the most limiting amino acids in all treatment diet samples. In conclusion, grain-free diet formulation could result in good protein quality in canine diets and extrusion processing increased amino acid digestibility and protein quality.

A review on fused deposition modeling (FDM)-based additive manufacturing (AM) methods, materials and applications for flexible fabric structures

Fused Deposition Modeling (FDM) is an extrusion type additive manufacturing (AM) method in which a molten polymer is selectively extruded in layer-by-layer manner. Although there are several other AM techniques, FDM is a suitable method to produce fabric structures as it is capable of processing polymers and is widely used in various engineering applications. This article summarizes the current research works in characterization of FDM parts, advancements in materials used in FDM and latest works related to making fabric samples using FDM. The results show that the mechanical properties and surface quality are compromised in FDM parts. Strength and flexibility with better surface finishing are essential parameters in fabric structures. There are mainly two techniques that are explored by researchers to enhance the quality of the parts. The first is optimizing process parameters and the second is improving material quality. FDM process parameters like extrusion temperature, layer height, print speed and built orientation can significantly influence the quality of the parts. Optimizing these parameters can significantly enhance the strength of the fabric produced. Moreover, a great amount of impetus is given to improve material by reinforcing it and making polymer blends with specific qualities. There has been studies related to the development of fabric structures and deposition of polymers on fabrics with FDM. It is concluded that the major concern with such structures is strength and processability. To address these issues, optimizing process parameters and developing new filaments for exclusively making fabrics can be the future work in this area.

Pengaruh Sudut Part Build Orientation Z-Direction Terhadap Kuat Tarik Spesimen Uji Standar Astm D638 Type IV Menggunakan Filamen Pla+

This study will try to investigate variations in the angle of the Z-direction build part by using a 3D Printer with Fused Deposition Modeling (FDM) technology made from PLA + Sugoi. This study uses a 0.4mm nozzle with a Bowden type extruder. This study uses a PLA+ filament from the Sugoi brand with a nozzle of 0.4 mm, diameter filament 1,75 mm, 3D Printer with Fused Deposition Modeling (FDM) technology used is Creality Ender 3 V2 with process parameter settings in slicing software using a layer thickness of 0.30 mm, Top solid Layer 5, Bottom Solid Layer 5, Fill density 100%, cooling speed 100%, and flowrate 100%, nozzle temperature 205°C, and bed temperature 60°C. Variation in angle Part build Z-direction is proven to have a significant difference in Tensile strength with a difference of 10° resulting in a difference in Tensile strength of 15 MPa, where the highest tensile strength is 67.50 MPa with part build Z-direction at an angle of 80°, and the lowest tensile strength of 52.50 MPa with a Z-direction part build angle at an angle of 70°.

Comparing the microstructural and mechanical improvements of AZ80/SiC nanocomposite using DECLE and MDF processes

The present study investigates the effects of two different severe plastic deformation (SPD) processes on an annealed AZ80/SiC nanocomposite. Specifically, the microstructure, texture, shear behavior, and hardness of the material were analyzed after being subjected to dual equal channel lateral extrusion (DECLE) for up to 5 passes, and multidirectional forging (MDF) for up to 8 passes, both carried out at a constant temperature of 300 °C. The effective strain was 1.44 and 0.5 in each DECLE and MDF pass. The annealed AZ80/SiC nanocomposite showed a reduction in average grain size from 68.4 μm to 2.7, 4.2, and 4.4 μm during 1, 3, and 5 passes of DECLE process, and to 8, 4.3, 2.3, and 5.4 μm during 2, 4, 6, and 8 passes of MDF process. Examination of the shear properties revealed that the ultimate shear strength (USS) of the nanocomposite increased after conducting both the DECLE and MDF processes. Specifically, the USS of the annealed nanocomposite increased by 23.1 MPa after 5 passes of the DECLE process and by 8.1 MPa after 8 passes of the MDF process. These results indicate that the DECLE process had a greater effect on the shear strength increase compared to the MDF process. The results of the hardness testing on the AZ80/SiC nanocomposite showed that the fifth pass of the DECLE process increased the hardness from 86.6 to 96.2 Hv, while the eighth pass of the MDF process increased this value to 90.1 Hv. The DECLE process was found to be more effective than the MDF process due to the simultaneous application of three types of shear deformation, pressing, and extrusion in each pass, as well as the higher effective strain.

Investigation of boiling heat transfer process in the barrel of a gravity heat pipe type extruder

Gravity heat pipe barrels produce gas films during the processing of thermoplastic materials, which affect the heat transfer, so there is an urgent need to study the nucleate boiling process and mechanism at different locations in the barrel. The results showed that the local heat flux at the vapor-liquid-solid three-phase contact was the largest, and different process conditions had different effects on the departure diameter and departure time of boiling bubbles. The tail vortex disturbance generated by bubble departure drives the merging and growth of bubbles to departure, which in turn improves the heat transfer. The rounded bottom of the barrel reduced the air film and increased the heat transfer efficiency compared to the horizontal bottom of the barrel. This study can deepen the understanding of the mechanism of bubble boiling heat exchange in gravity heat pipe-type barrels and provide theoretical support for more relevant application scenarios.

PERFORMANCE ANALYSIS OF BIO-BRIQUETTING MACHINE WITH SCREW EXTRUDER TYPE BASED ON QUALITY OF BIO-BRIQUETTES

he purpose of this study is to design a bio-briquetting machine with screw extruder type to convert biomass into higher density based on quality standard of charcoal briquette SNI 01-6235-2000 and SNI 19-4791-1998. The machine had production capacity of 30 kg/hour, equipped with the motor of 1 HP which transmitted to the machine through pulley and belt, and also has cutter which rotates continuously. The raw materials of the bio-briquette were using bagasse and coconut shells. There are 6 parameters that are used to test the quality of bio-briquette such as calorific value, inherent moisture, ash content, dependability pressure, volatile matter content, and fixed carbon content. The bio-briquette was made from the raw materials using amylum adhesives with ratio 30:70:30. With feed as 5 kg, the machine produced 50 pieces of bio-briquette. The machine could produce good bio-briquettes such as calorific value of 6,511.3 cal/g, inherent moisture of 1.97%, ash content of 5.88%, volatile matter of 27.71%, fixed carbon content of 64.99% and compressive strength was 16.98 kg/cm2.

Highly conductive and stretchable filament for flexible electronics

Conductive and stretchable filaments are crucial for advancing additive manufacturing, particularly in flexible electronics. However, existing conductive filaments suffer from limitations in conductivity and stretchability. To overcome these challenges, this study presents a highly conductive and stretchable filament for material extrusion type 3D printing. The developed filament achieves an initial electrical conductivity of 558 S/cm and maintains low resistance up to 60 % strain with 10 vol% silver loading. This significantly surpasses the performance of commercial filaments and previous literature reports. The addition of polyethylene glycol (PEG) as a plasticizer for the silver filled thermoplastic polyurethane (Ag-TPU) composite enhances extrusion and improves filament surface quality. The printability of the filament in material extrusion 3D printing was evaluated, and the electrical conductivity of the printed objects was assessed. Two demonstrator structures, an electrical interconnection and a capacitive strain sensor, were successfully prototyped, showcasing the potential applications of this filament in stretchable electronics. The developed filament paves the way for creating intricate and stretchable electronic devices using material extrusion printing techniques. These advancements contribute to the field of additive manufacturing and enable the fabrication of flexible electronic components with enhanced conductivity and stretchability.

Development of hybrid multi-head, multi-material paste and ink extrusion type 3D printer for biomedical applications

ABSTRACT Additive manufacturing is a fabrication technique where materials are built up layer-by-layer allowing the realization of complex designs. Ceramic additive manufacturing is steadily increasing in the market and industries are developing 3D printers that are economical and efficient to print single/multi-material. The development of free-form extrusion-type printers has been of great significance due to their wide range of materials used, availability of technology, low development cost, and design freedom in developing the structures. We have successfully developed a hybrid multi-head 3D printer with four print heads capable of operating individually or together to print multiple layers using different materials. The three mechanically actuated print heads are provided to print ceramic, metallic slurry, and polymeric materials, and one pneumatic actuated print head is for printing bio-ink. The developed hybrid multi-head 3D printer can be beneficial in printing a wide range of materials such as metals, ceramics, polymers, and composites due to its flexibility in printing materials of different viscosities at different pressure. The optimization of the printing of calcium silicate bio-ceramics and multi-material is also studied and reported.

Analisis Kekuatan Tarik dan Regangan Filamen Carbon Fiber Hasil 3D Print dengan Variasi Fill Density

Mechanical properties problems that are closely related to the strength of 3D printed products generally occur during the development of 3D printing machines, In which several components used are the results of additive manufacturing technology. The damages generally occur in the components that receive force and the damage is in the form of cracks and fractures. The focus of this study is to determine the effects of increasing the value of fill density on mechanical properties, especially tensile strength and strain with carbon fiber filament material. This study used an experimental method using two types of filament material: nylon carbon fiber and PLA carbon fiber with a diameter of 1.75 mm for each filament and a recommended printing temperature of 190-260°C. Both types of filaments were printed using a direct extruder type 3D printing machine with a build size of 180 mm x 180 mm x 180 mm and printing was carried out at atmospheric pressure and a horizontal printing area. The Universal Testing Machine carried out mechanical properties testing implementation related to tensile strength and strain. Based on the results of experiments and tests that have been carried out, the strain values ​​are 16.970 – 26.681% and the tensile strength is 19.244 – 23.899 MPa for nylon carbon fiber filament material. Whereas the PLA carbon fiber filament material, the strain value is 7.673 – 15.546%, and the tensile strength is 18.580 – 24.552 MPa. Therefore, based on the test results, it is known that the fill density parameter value has an influence on the strain value and tensile strength so that it can be used as a reference in setting machining parameters.

Modeling of mixing process of the polymer composition in the dynamic mixer of the worm extruder

Mixing processes play an important role in the processing of polymer materials, because the quality of the mixing of the polymer material depends on its level of homogeneity, which in turn affects the quality of the final product. It is another matter when the polymer material consists of two or more components, in this case, the issue of the process of obtaining a homogeneous polymer composition becomes extremely acute. In order to improve the quality of the final product and justify the design and technological parameters of the mixing zone, it is necessary to investigate the regularity of the quality of mixing in a dynamic mixer of the CTM worm extruder type.
 According to existing works on determining the quality of mixing of polymeric material, the difference in concentrations of one of the components in different cross-sections along the length of the channel can be used as a criterion for homogeneity of mixing.
 Numerical modeling of the process of mixing the polymer composition in the dynamic mixer installed in the dosing zone of the worm extruder, which is equipped with an additional injection device that supplies the additional component to the dynamic mixing zone through the injection channel located in the body of the worm extruder, was carried out. Calculations were carried out on the basis of the finite element method (FEM) using the ANSYS software complex.
 A mathematical model of the process of mixing the polymer composition in a dynamic mixer of the CTM type of a worm extruder with the addition of an additional component, which is identical in density and viscosity to the main polymer material and can differ only in a certain feature that does not affect the properties of the components, such as color, has been developed. Moreover, the properties were set in such a way that the temperature distribution of the mixture was completely determined by the convective component, that is, it resulted only from the conditions of the mechanical movement of the volumes of the components.
 The dependence of the homogeneity of the polymer composition as a result of mixing on the technological and design parameters of the dynamic mixer of the CTM type was obtained. The research was carried out at different speeds of rotation of the mixer rotor and at different speeds of supplying the additional component. The movement of the components of the mixture was determined by their flow rate at the entrance to the main channel and at the entrance to the additional injection channel.
 The most optimal technical characteristics were selected in order to achieve the best level of uniformity.

Was a 3D-printed firearm discharged? Study of traces produced by the use of six fully 3D-printed firearms

Since the blueprints of the Liberator were published and successfully tested, countless new designs for said 3D-printed firearms and 3D-printed firearm components have been created and made publicly available. These new 3D-printed firearms, which are praised by their designers as ever more reliable, can be found on the Internet with little effort. Press reports have shown that various models of 3D-printed firearms have already been confiscated by law enforcement services around the world. So far, forensic studies have addressed this set of problems relatively little, whereby for the most part only the Liberator has been examined in detail and three other designs were only included a few times. The rapid pace of this development poses new challenges for forensic investigations and unveils new spheres of investigation regarding 3D-printed firearms. This research initiative aims to determine whether the results from previous studies on Liberators, are also reproducible and observable when using other models of 3D-printed firearms. In this respect six fully 3D-printed firearms – PM422 Songbird, PM522 Washbear, TREVOR, TESSA, Marvel Revolver and Grizzly – were produced on a material extrusion type Prusa i3 MK3S using PLA as the material. Test firings of these 3D-printed firearms have shown that they are indeed functional, but that, depending on the model, they suffer different levels of damage when fired. However, they were all rendered inoperative after one discharge and could not be used for further discharges unless the broken pieces were replaced. As in other studies, the firing process and the resulting ruptures on the 3D-printed firearm, projected polymer parts and fragments of different sizes and in different quantities into the immediate environment. The parts could be physically matched, allowing the reconstruction and identification of the 3D-printed firearms. Elements of ammunition also showed traces of melted polymer on the surface and cartridge cases bore tears or swellings.

An Investigation of Printing Parameters of Independent Extrusion Type 3D Print Continuous Carbon Fiber-Reinforced PLA

Fused filament fabrication (FFF) technology is highly favored by various industries as the simplest and most commonly used technology in additive manufacturing. The embedding of continuous fiber-reinforced thermoplastic composites (CFRTC) is a great help to compensate for the mechanical properties of FFF-printed specimens. In this paper, the optimal printing parameters of printed specimens containing continuous carbon fiber-reinforced PLA were investigated by the Taguchi method, full factorial analysis, and the tensile test. Fiber printing layer thickness and fiber printing speed are significant factors. After excluding the influence of fiber overlap, the optimal printing parameters were obtained. When the thickness of the fiber printing layer is 0.05 mm, the speed of the fiber printing nozzle is 250 mm/min, and the temperature of the fiber printing nozzle is 210 °C, the maximum tensile stress of the sample is 189.52 MPa. In this paper, the maximum tensile stress of the specimen printed by different printing parameters can be doubled, which shows the influence of printing parameters on the mechanical properties of the specimen. Compared with the specimen using pure PLA printing, the increase was 703.5%. Then the failure mechanism of 3D-printed CFRTC specimens with different layer thicknesses was investigated by using microstructural morphology and tensile fracture interfacial property analysis. The influence of layer thickness parameters on the interfacial bonding force was revealed. Through analysis, it is found that the lower the thickness of the specimen printing layer, the better the interface bonding force of the specimen, and the minimum layer thickness suitable for FFF independent extrusion printer is found.

An investigation of preparation of continuous carbon fiber reinforced PLA prepreg filament

Continuous fiber reinforced thermoplastic composite (CFRTC) 3D printing technology has been a hot research topic in the field of additive manufacturing in recent years. This technology greatly improves the mechanical properties of printed parts by adding continuous reinforced fiber to the thermoplastic polymer. This paper investigates the production of prepreg filaments for “independent extrusion” type Fused Deposition Modeling (FDM) 3D printing. Firstly, suitable impregnation process and materials are selected, and not only the overall design of the prepreg equipment is carried out but also combined with the impregnation theory and simulation to determine the structure of each impregnation mould. Finally, based on the prepreg equipment, continuous carbon fiber reinforced PLA prepreg filament is made. And 3D printing test was conducted. The equipment successfully manufactured continuous carbon fiber reinforced PLA prepreg with a diameter of about 0.38 mm and a monofilament tensile strength of 1200 MPa. The tensile strength of the printed parts reached 620 MPa by printing through an independent extrusion type 3D printer.

Improved Extrusion Cooking Technology: A Mini Review Of Starch Modification

ABSTRACT In the literature, there are several articles that worked with what they called improved extrusion cooking technology (IECT), which is an innovative machine for the modification of starch, obtained from the traditional screw extruder. This review focused on the advances in the application of the IECT used in food processing, from the perspective of the results obtained in some physicochemical properties. Interesting results have been obtained, such as significant starch gelatinization at a moisture content of 70% and a screw speed of 37 rpm. In the index of water absorption and water solubility, a variety of results are obtained, depending on the process conditions. The IECT has potential applying it not only to the modification of starch, but also comparing it with other types of extruders, with the intention of increasing and diversify the results for their potential use in food.

Effects of pea protein content and extrusion types on physicochemical properties and texture characteristic of meat analogs

AbstractBackgroundWith the change in consumers' lifestyles, the global demand for meat analogs is growing rapidly. However, soy has many drawbacks as a raw material to produce meat analogs, such as its allergy potential (glycinin and β‐conglycinin) and some unpredictable alterations in genetic DNA, proteins, and biochemical processing due to genetic modification. This paper aims to study the physicochemical and textural properties of meat analogs obtained under different pea protein contents and extrusion types to explore the potential of applying pea protein to meat analogs.ResultsHigh‐moisture meat analog (HMMA) is superior to low‐moisture meat analog (LMMA) based on the physical properties (integrity index and nitrogen solubility index) and texture properties (texture profile analysis and cutting strength). The higher the amount of pea protein added, the higher the degree of sample texturization. At low‐moisture extrusion cooking (LMEC), higher isolated pea protein content is accompanied by lower water holding capacity and higher texturization. Hydrophobic interactions play a slightly greater role than disulfide bonds in stabilizing the protein structure of the extrudates. The type of extrusion significantly affected the free sulfhydryl and disulfide bond content of the extrudate, while the source of raw material has an important relationship with protein solubility and free sulfhydryl content. Dodecyl sulfated gel electrophoresis (SDS‐PAGE) showed that most of the protein subunits remained after extrusion.ConclusionsExtrusion types and isolated pea protein contents showed significant effects on the properties of meat analogs, and isolated pea protein has great potential for application in the production of meat analogs.

WEIGHT BEARING 3-D JOINT SPACE WIDTH DISTRIBUTION AT THE KNEE VARIES ACCORDING TO LOCATION AND EXTENT OF MENISCAL EXTRUSION: A MOST INVESTIGATION

Quantitative 3-D measurement of joint space width (JSW) from weight bearing computed tomography (WBCT) allows analysis of knee tibiofemoral compartments in a loaded stance without subregional constraints on analysis. The relationship between 3-D JSW distribution and meniscal extrusion is yet to be established. To demonstrate topographic variations in 3-D JSW distribution at the knee derived from WBCT imaging data according to meniscal extrusion location and extent. WBCT knee imaging was acquired at the 144-month visit of the Multicenter Osteoarthritis Study (MOST). A subset of individuals had medial and lateral meniscal extrusion grading according to the MRI Osteoarthritis Knee Score to identify medial extrusion of the medial meniscus (MMmed), anterior extrusion of the medial meniscus (MMant), anterior extrusion of the lateral meniscus (LMant), and lateral extrusion of the lateral meniscus (LMlat). The extent of extrusion was graded as 0: <2 mm; 1: 2 to 2.9 mm, 2: 3 to 4.9 mm; and 3: >5 mm. After semi-automatic segmentation of 663 baseline knees, joint space mapping was performed to create 3-D JSW maps for each knee registered to a template surface. Statistical parametric mapping (SPM) was performed using a general linear model to test the dependence of 3-D JSW distribution on each of meniscal extrusion type in turn. SPM results were plotted on the canonical joint surface, with unmasked regions demonstrating the topographic difference in JSW for each increment in extrusion score. 568 knees from 330 participants had meniscal extrusion grading available. Participants (178 female) had mean ± SD age 62.0 ± 9.3 years, body mass 82.2 ± 17.4 kg, height 170 ± 9.5 cm, and BMI 28.3 ± 4.8 kg/m2. Analysed knees were bilateral for 238 participants and unilateral for 92 participants. For MMmed (cohort score range 0-3), the central-to-posterior medial compartment had significantly lower JSW by up to 0.4 mm for each increment in meniscal extrusion grade. Both MMmed and MMant (score range 0-3) were associated with a small region of similarly significantly lower JSW along the medial margin of the lateral compartment, but also with significantly greater JSW at the anterior medial compartment of up to 0.6 mm per grade. The posterior medial joint space was significantly narrower (up to 3 mm) comparing knees with LMant scores of 0 vs 1. This same magnitude of narrowed JSW was detected along the periphery of the lateral joint space comparing grades in the lateral tibiofemoral compartment, but this was not statistically significant. LMlat (score range 0-2) was associated with a trend for greater reduction in JSW in the central lateral compartment of up to 0.5 mm per grade, but this was not statistically significant. Direction of meniscal extrusion is represented by the black arrowhead in the figure. Both medial and anterior extrusion of the medial meniscus are associated with significant reduction in JSW at the medial margin of the lateral joint space and widening of the anterior margin, likely from a posteromedial shift of the femoral condyles with respect to the tibia. Medial extrusion of the medial meniscus is also associated with narrowed JSW in the central to posterior medial joint space, likely as a direct effect of the loss of meniscal hoop tension. Anterior (but not lateral) extrusion of the lateral meniscus is associated with significantly lower JSW in the posterior medial joint space. These findings confirm that the extent and location of meniscal extrusion are key factors in weight bearing 3-D JSW distribution.