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18 pages, 674 KiB  
Article
Oil Extraction Systems Influence the Techno-Functional and Nutritional Properties of Pistachio Processing By-Products
by Rito J. Mendoza-Pérez, Elena Álvarez-Olmedo, Ainhoa Vicente, Felicidad Ronda and Pedro A. Caballero
Foods 2025, 14(15), 2722; https://doi.org/10.3390/foods14152722 - 4 Aug 2025
Viewed by 42
Abstract
Low-commercial-value natural pistachios (broken, closed, or immature) can be revalorised through oil extraction, obtaining a high-quality oil and partially defatted flour as by-product. This study evaluated the techno-functional and nutritional properties of the flours obtained by hydraulic press (HP) and single-screw press (SSP) [...] Read more.
Low-commercial-value natural pistachios (broken, closed, or immature) can be revalorised through oil extraction, obtaining a high-quality oil and partially defatted flour as by-product. This study evaluated the techno-functional and nutritional properties of the flours obtained by hydraulic press (HP) and single-screw press (SSP) systems, combined with pretreatment at 25 °C and 60 °C. The extraction method significantly influenced flour’s characteristics, underscoring the need to tailor processing conditions to the specific technological requirements of each food application. HP-derived flours presented lighter colour, greater tocopherol content, and higher water absorption capacity (up to 2.75 g/g), suggesting preservation of hydrophilic proteins. SSP-derived flours showed higher concentration of protein (44 g/100 g), fibre (12 g/100 g), and minerals, and improved emulsifying properties, enhancing their suitability for emulsified products. Pretreatment at 25 °C enhanced functional properties such as swelling power (~7.0 g/g) and water absorption index (~5.7 g/g). The SSP system achieved the highest oil extraction yield, with no significant effect of pretreatment temperature. The oils extracted showed high levels of unsaturated fatty acids, particularly oleic acid (~48% of ω-9), highlighting their nutritional and industrial value. The findings support the valorisation of pistachio oil extraction by-products as functional food ingredients, offering a promising strategy for reducing food waste and promoting circular economy approaches in the agri-food sector. Full article
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27 pages, 6819 KiB  
Article
Employing Polymer and Gel to Fabricate Scaffold-like Cancellous Orthopedic Screw: Polycaprolactone/Chitosan/Hydroxyapatite
by AmirHossein Badami, Javad Esmaeili and Hasan Mirtalaie
Gels 2025, 11(1), 28; https://doi.org/10.3390/gels11010028 - 2 Jan 2025
Viewed by 1184
Abstract
Using metallic/polymeric orthopedic screws causes cavities in bone trauma after the attachment of broken bones, which prolongs the healing. Yet, it remains unknown how to overcome such a challenge. The main aim of this research was to use both polymers and gels to [...] Read more.
Using metallic/polymeric orthopedic screws causes cavities in bone trauma after the attachment of broken bones, which prolongs the healing. Yet, it remains unknown how to overcome such a challenge. The main aim of this research was to use both polymers and gels to fabricate and study a new PCL/chitosan/hydroxyapatite scaffold-like orthopedic screw for cancellous bone trauma. This screw, because of its low stiffness and its scaffold-based matrix (due to the gel part), can facilitate bone healing. Different concentrations of PCL (60–95% w/v) and chitosan (0–5% w/v) were blended according to the Response Surface Methodology using the Central Composite Design. The screws were fabricated using the freeze-drying technique. The screws were assessed mechanically, physically, and biologically (cell viability, cell attachment, DAPI, ALP staining, and Alizarin Red staining), and in vivo (a rat subcutaneous implantation model). Based on the results, screws depending on the PCL and gel content depicted different but notable mechanical behavior (10–60 MPa of compressive strength and 100–600 N force). The gel part could affect the physical properties of screws including water uptake (120%), degradation (18% after 21 days), porosities (23%), and mechanical strength (elastic modulus = 59.47 Mpa). The results also demonstrated no cytotoxicity towards MC3T3 cells (>80% cell viability) with good cell attachment, cell concentration, and mineralization (>90%) that was justified by the gel content. The results also showed good in vivo biocompatibility. To sum up, fabricated scaffold-like screws with gel content can be a good candidate for cancellous-bone-based orthopedic purposes. However, more in vitro and in vivo studies are required to optimize the PCL:gel ratio. Full article
(This article belongs to the Special Issue Hydrogels for Bone Regeneration)
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11 pages, 2752 KiB  
Article
Encapsulation of ɣ-Aminobutyric Acid Compounds Extracted from Germinated Brown Rice by Freeze-Drying Technique
by Tarinee Nilkamheang, Chanikarn Thanaseelangkoon, Rawinan Sangsue, Sarunya Parisaka, Le Ke Nghiep, Pitchaporn Wanyo, Nitchara Toontom and Kukiat Tudpor
Molecules 2024, 29(21), 5119; https://doi.org/10.3390/molecules29215119 - 30 Oct 2024
Cited by 2 | Viewed by 1132
Abstract
Gamma-aminobutyric acid (GABA) from plants has several bioactivities, such as neurotransmission, anti-cancer cell proliferation, and blood pressure control. Its bioactivities vary when exposed to pH, heat, and ultraviolet. This study analyzed the protective effect of the GABA encapsulation technique using gum arabic (GA) [...] Read more.
Gamma-aminobutyric acid (GABA) from plants has several bioactivities, such as neurotransmission, anti-cancer cell proliferation, and blood pressure control. Its bioactivities vary when exposed to pH, heat, and ultraviolet. This study analyzed the protective effect of the GABA encapsulation technique using gum arabic (GA) and maltodextrin (MD) and the freeze-drying method. The impact of different ratios of the wall material GA and MD on morphology, GABA content, antioxidant activity, encapsulation efficiency, process yield, and physical properties were analyzed. Results showed that the structure of encapsulated GABA powder was similar to broken glass pieces of various sizes and irregular shapes. The highest GABA content and encapsulation efficiency were, respectively, 90.77 mg/g and 84.36% when using the wall material GA:MD ratio of 2:2. The encapsulated powder’s antioxidant activity was 1.09–1.80 g of encapsulation powder for each formula, which showed no significant difference. GA and MD as the wall material in a 2:2 (w/w) ratio showed the lowest bulk density. The high amount of MD showed the highest Hausner ratio (HR), and Carr’s index (CI) showed high encapsulation efficiency and process yield. The stability of encapsulated GABA powder can be kept in clear glass with a screw cap at 35 °C for 42 days compared to the non-encapsulated one, which can be preserved for only 18 days under the same condition. In conclusion, this study demonstrated that the freeze-drying process for GABA encapsulation preserved GABA component extracts from brown rice while increasing its potential beneficial properties. Using a wall material GA:MD ratio of 2:2 resulted in the maximum GABA content, solubility, and encapsulation efficiency while having the lowest bulk density. Full article
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15 pages, 8413 KiB  
Article
Dental Implant Abutment Screw Loss: Presentation of 10 Cases
by Maryam Soleimani, Jarosław Żmudzki, Wojciech Pakieła, Anna Jaśkowska and Kornel Krasny
J. Funct. Biomater. 2024, 15(4), 96; https://doi.org/10.3390/jfb15040096 - 9 Apr 2024
Cited by 1 | Viewed by 3214
Abstract
Re-tightening the loosened dental implant abutment screw is an accepted procedure, however the evidence that such screw will hold sufficiently is weak. The purpose of this study was material analysis of lost dental implant abutment screws made of the TiAlV alloy from various [...] Read more.
Re-tightening the loosened dental implant abutment screw is an accepted procedure, however the evidence that such screw will hold sufficiently is weak. The purpose of this study was material analysis of lost dental implant abutment screws made of the TiAlV alloy from various manufacturers, which became lost due to unscrewing or damaged when checking if unscrewed; undamaged screws could be safely re-tightened. Among 13 failed screws retrieved from 10 cases, 10 screws were removed due to untightening and 3 were broken but without mechanical damage at the threads. Advanced corrosion was found on nine screws after 2 years of working time on all surfaces, also not mechanically loaded. Sediments observed especially in the thread area did not affect the corrosion process because of no pit densification around sediments. Pitting corrosion visible in all long-used screws raises the question of whether the screws should be replaced after a certain period during service, even if they are well-tightened. This requires further research on the influence of the degree of corrosion on the loss of the load-bearing ability of the screw. Full article
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15 pages, 3460 KiB  
Article
Impact of Oat Supplementation on the Structure, Digestibility, and Sensory Properties of Extruded Instant Rice
by Junling Wu, Kai Zhu, Sijie Zhang, Meng Shi and Luyan Liao
Foods 2024, 13(2), 217; https://doi.org/10.3390/foods13020217 - 10 Jan 2024
Cited by 9 | Viewed by 1879
Abstract
The addition of oat at varying percentages (26%, 32%, 38%, 44% and 50%) was used to evaluate the structural, microstructural, and physicochemical changes in instant-extruded rice (IER). A mixture of broken rice and oat flour was extruded in a twin-screw extruder. It was [...] Read more.
The addition of oat at varying percentages (26%, 32%, 38%, 44% and 50%) was used to evaluate the structural, microstructural, and physicochemical changes in instant-extruded rice (IER). A mixture of broken rice and oat flour was extruded in a twin-screw extruder. It was found that when adding 44% oats, the gelatinization degree of the mixed powder was the lowest (89.086 ± 1.966%). The dietary fiber content increased correspondingly with the increase in oat addition. Analyses of texture properties revealed that the hardness, adhesive, and resilience values increased and then decreased with oat addition. Compared with other common instant rice (IR), the advantages of IER were evaluated in terms of microstructure, digestive performance, and flavor. IER with 44% oat addition obtained in this study had higher hardness, adhesiveness, rehydration time, and sensory score, and the content of resistant starch (RS) reached 6.06%. The electronic nose and electronic tongue analyses could distinguish the flavor of different IR efficiently. This study showed the feasibility of preparing fiber-enriched IER. The results demonstrated the potential for the development and utilization of broken rice, providing a reference for the development of IER. Full article
(This article belongs to the Special Issue Extrusion Technologies Applied in Food Industry)
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9 pages, 5915 KiB  
Article
Risk Factors of Proximal Screw Breakage of Locking Plate (ZPLP®) after MIPO for Distal Femur Fractures -Analysis of Patients with Plate Removal after Bony Union-
by Jehyun Yoo, Daekyung Kwak, Joongil Kim, Seungcheol Kwon, Junhyuk Kwon and Jihyo Hwang
J. Clin. Med. 2023, 12(19), 6345; https://doi.org/10.3390/jcm12196345 - 3 Oct 2023
Cited by 2 | Viewed by 1896
Abstract
Background: Locking a compression plate is a more favorable surgical technique than intramedullary nailing in the treatment of distal femur fractures. This study analyzed the risk factors of proximal screw breakage retrospectively, which was confirmed in the patients with plate removal after bony [...] Read more.
Background: Locking a compression plate is a more favorable surgical technique than intramedullary nailing in the treatment of distal femur fractures. This study analyzed the risk factors of proximal screw breakage retrospectively, which was confirmed in the patients with plate removal after bony union. Methods: A total of 140 patients who were fixed by MIPO using ZPLP from 2009 to 2019 were identified. A total of 42 patients met the inclusion criteria and were included. The screw breakage group (12 patients) and the non-breakage group (30 patients) were compared. Results: Approximately 12 (28.6%) of 42 plate-removal patients showed proximal screw breakage. The breakage of proximal screws developed at the junction of the screw head and neck. The number of broken proximal screws averaged 1.4 (1~4). The breakage of the proximal screw even after the bony union is more frequent in older patients (p = 0.023), the dominant side (p = 0.025), the use of the cortical screw as the proximal uppermost screw (p = 0.039), and the higher plate-screw density (p = 0.048). Conclusions: Advanced age, dominant side, use of the cortical screw as the uppermost screw, and higher plate-screw density were related to proximal screw breakage. When the plate is removed after bony union or delayed union is shown in these situations, the possibility of proximal screw breakage should be kept in mind. Full article
(This article belongs to the Special Issue Orthopaedic Trauma Surgery: Diagnosis, Treatment and Outcome)
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20 pages, 5858 KiB  
Article
Development and Process Optimization of a Ready-to-Eat Snack from Rice-Cowpea Composite by a Twin Extruder
by Abiodun Afolabi Okunola, Ewhoritsemogha Priscilla Dottie, Olumuyiwa Isaac Moses, Timothy Adesoye Adekanye, Clinton E. Okonkwo, Mohammad Kaveh, Mariusz Szymanek and Charity O. Aremu
Processes 2023, 11(7), 2159; https://doi.org/10.3390/pr11072159 - 19 Jul 2023
Cited by 5 | Viewed by 1950
Abstract
A central composite rotatable design with four independent variables viz. blend ratio (broken rice flour and cowpea flour): 90:10–70:30, moisture content (10–18% wet basis), barrel temperature (110–150 °C), and screw speed (280–360 rpm) were varied in the development of ready-to-eat snacks using a [...] Read more.
A central composite rotatable design with four independent variables viz. blend ratio (broken rice flour and cowpea flour): 90:10–70:30, moisture content (10–18% wet basis), barrel temperature (110–150 °C), and screw speed (280–360 rpm) were varied in the development of ready-to-eat snacks using a twin extruder for a broken rice–cowpea product. The effects of the independent variables on specific mechanical energy, water absorption index, water solubility index, total color, hardness, bulk density, expansion ratio, and overall acceptability of the extruded snack were investigated using regression analysis. The results showed that the physical qualities of the ready-to-eat snacks were significantly affected by the extrusion parameters (i.e., blend ratio, barrel temperature, moisture content, and screw speed). From the findings, it was observed that screw speed and moisture contents affected hardness, while water absorption index was affected by all the extrusion parameters. However, the water solubility index and overall acceptance were majorly affected by the moisture content; extrudate produced with barrel ratio of 85:15, 12% moisture content, barrel temperature of 140 °C, and screw speed of 300 rpm was the most acceptable, at 6.73 on a 9 point hedonic scales. The blend ratio and barrel temperature influenced the expansion. Furthermore, the combination of cowpea and broken rice to produce nutritious ready-to-eat snacks has high acceptability and is a promising panacea for food security. Full article
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17 pages, 10576 KiB  
Article
Design of Proposed Software System for Prediction of Iliosacral Screw Placement for Iliosacral Joint Injuries Based on X-ray and CT Images
by Vojtech Benda, Jan Kubicek, Roman Madeja, David Oczka, Martin Cerny and Kamila Dostalova
J. Clin. Med. 2023, 12(6), 2138; https://doi.org/10.3390/jcm12062138 - 9 Mar 2023
Viewed by 1629
Abstract
One of the crucial tasks for the planning of surgery of the iliosacral joint is placing an iliosacral screw with the goal of fixing broken parts of the pelvis. Tracking of proper screw trajectory is usually done in the preoperative phase by the [...] Read more.
One of the crucial tasks for the planning of surgery of the iliosacral joint is placing an iliosacral screw with the goal of fixing broken parts of the pelvis. Tracking of proper screw trajectory is usually done in the preoperative phase by the acquisition of X-ray images under different angles, which guide the surgeons to perform surgery. This approach is standardly complicated due to the investigation of 2D X-ray images not showing spatial perspective. Therefore, in this pilot study, we propose complex software tools which are aimed at making a simulation model of reconstructed CT (DDR) images with a virtual iliosacral screw to guide the surgery process. This pilot study presents the testing for two clinical cases to reveal the initial performance and usability of this software in clinical conditions. This model is consequently used for a multiregional registration with reference intraoperative X-ray images to select the slide from the 3D dataset which best fits with reference X-ray. The proposed software solution utilizes input CT slices of the pelvis area to create a segmentation model of individual bone components. Consequently, a model of an iliosacral screw is inserted into this model. In the next step, we propose the software CT2DDR which makes DDR projections with the iliosacral screw. In the last step, we propose a multimodal registration procedure, which performs registration of a selected number of slices with reference X-ray, and based on the Structural Similarity Index (SSIM) and index of correlation, the procedure finds the best match of DDR with X-ray images. In this pilot study, we also provide a comparative analysis of the computational costs of the multimodal registration upon various numbers of DDR slices to show the complex software performance. The proposed complex model has versatile usage for modeling and surgery planning of the pelvis area in fractures of iliosacral joints. Full article
(This article belongs to the Section Nuclear Medicine & Radiology)
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21 pages, 6877 KiB  
Article
Simulation and Experimental Validation on the Effect of Twin-Screw Pulping Technology upon Straw Pulping Performance Based on Tavares Mathematical Model
by Huiting Cheng, Yuanjuan Gong, Nan Zhao, Luji Zhang, Dongqing Lv and Dezhi Ren
Processes 2022, 10(11), 2336; https://doi.org/10.3390/pr10112336 - 9 Nov 2022
Cited by 8 | Viewed by 2145
Abstract
Rice straw is waste material from agriculture as a renewable biomass resource, but the black liquor produced by straw pulping causes serious pollution problems. The twin-screw pulping machine was designed by Solidworks software and the straw breakage model was created by the Discrete [...] Read more.
Rice straw is waste material from agriculture as a renewable biomass resource, but the black liquor produced by straw pulping causes serious pollution problems. The twin-screw pulping machine was designed by Solidworks software and the straw breakage model was created by the Discrete Element Method (DEM). The model of straw particles breakage process in the Twin-screw pulping machine was built by the Tavares model. The simulation results showed that the highest number of broken straw particles was achieved when the twin-screw spiral casing combination was negative-positive-negative-positive and the tooth groove angle arrangement of the negative spiral casing was 45°−30°−15°. The multi-factor simulation showed that the order of influence of each factor on the pulp yield was screw speed > straw moisture content > tooth groove angle. The Box-Behnken experiment showed that when screw speed was 550 r/min, tooth groove angle was 30°, straw moisture content was 65% and pulping yield achieved up to 92.5%. Twin-screw pulping performance verification experiments were conducted, and the results from the experimental measurements and simulation data from the model showed good agreement. Full article
(This article belongs to the Special Issue Biomass Conversion and Organic Waste Utilization)
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15 pages, 4448 KiB  
Article
Screw Analysis, Modeling and Experiment on the Mechanics of Tibia Orthopedic with the Ilizarov External Fixator
by Peng Su, Sikai Wang, Yuliang Lai, Qinran Zhang and Leiyu Zhang
Micromachines 2022, 13(6), 932; https://doi.org/10.3390/mi13060932 - 11 Jun 2022
Cited by 6 | Viewed by 5688
Abstract
The Ilizarov external fixator plays an important role in the correction of complex malformed limbs. Our purpose in this work was to reveal the transmission of adjustable forces between the external fixator and the broken bone, and express the stress distribution at the [...] Read more.
The Ilizarov external fixator plays an important role in the correction of complex malformed limbs. Our purpose in this work was to reveal the transmission of adjustable forces between the external fixator and the broken bone, and express the stress distribution at the end of the broken bone during the orthopedic treatment. Firstly, the screw model of the fixator was established and the theoretical relationship between the adjustable force and the stress was obtained. A sheep tibia was taken as a representative research object and its ediTable 3D entity was obtained by CT scanning. Then the mechanical model of the fixator and tibia was built using the ABAQUS software. Correction experiments were performed on the sheep tibia to measure the adjustable/support forces and tensions of the tibia. The measured results were imported to the screw and mechanical model, and the theoretical and simulation values were calculated. The theoretical tensions calculated by the screw model had a similar shape and doubled the value compared with that of the measured results. The transfer efficiency between the two results was improved and kept at about 50% after the initial 2~3 periods. The maximum stress occurring at the surface of the broken bone end was near the Kirschner wire pinhole. The simulation results for the tensions from the mechanical model showed a similar change trend, and the value was slightly higher. A biomechanical model of the Ilizarov external fixator was derived and verified through calculations, simulations and experiments. The change law of the adjustable forces and the tensions existing in the broken sheep tibias is presented herein, and offers a helpful contribution to orthopedic treatment. Full article
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12 pages, 3855 KiB  
Article
A Novel Distal Interlocking Screw Guidance System Using a Laser Pointer and a Mechanical Fine-Adjustment Device
by Binxiang Xu, Liming An and Seong Young Ko
Appl. Sci. 2021, 11(23), 11109; https://doi.org/10.3390/app112311109 - 23 Nov 2021
Viewed by 2607
Abstract
In minimally invasive bone fracture reduction surgery, broken femur bones are firmly fixed to a metallic intramedullary nail (IMN) after they are properly aligned. One of the greatest challenges of this process is that surgeons cannot directly see holes on the IMN, which [...] Read more.
In minimally invasive bone fracture reduction surgery, broken femur bones are firmly fixed to a metallic intramedullary nail (IMN) after they are properly aligned. One of the greatest challenges of this process is that surgeons cannot directly see holes on the IMN, which increases the difficulty of the procedure and results in the requirement of taking a large number of X-ray images to find the location and direction of holes. We propose a novel distal interlocking screw guidance system that consists of a parallel guidance system using a laser pointer (PGSLP) and a mechanical fine-adjustment device (FAD). The PGSLP is used to make the planes of the C-arm and FAD parallel. The FAD is used to concentrically align the IMN hole with the guiding hole. The performance of the proposed device was evaluated by a series of experiments. The tilted angle error between the C-arm and FAD was measured to be 1.24 ± 0.715°. The translational error between the IMN hole and guiding hole was measured to be 0.378 ± 0.120 mm. Since the proposed guiding system is simple, cost-effective, and accurate, we expect it will soon be used in real operations. Full article
(This article belongs to the Special Issue Frontiers in Medical Robotics)
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10 pages, 4118 KiB  
Article
Application of a Novel Attachable Magnetic Nerve Stimulating Probe in Intraoperative Lumbar Pedicle Screw Placement: A Porcine Model Study
by Tae Sik Goh, Sung-Chan Shin, Hyun-Keun Kwon, Eui-Suk Sung, Se Bin Jun, Byung-Joo Lee and Jung Sub Lee
Appl. Sci. 2021, 11(17), 7801; https://doi.org/10.3390/app11177801 - 25 Aug 2021
Viewed by 3102
Abstract
Pedicle screw instrumentation is a fundamental technique in lumbar spine surgery. However, several complications could occur when placing a pedicle screw, the most serious being damage to the neural structures. We developed an attachable magnetic nerve stimulating probe used for triggered electromyography (t-EMG) [...] Read more.
Pedicle screw instrumentation is a fundamental technique in lumbar spine surgery. However, several complications could occur when placing a pedicle screw, the most serious being damage to the neural structures. We developed an attachable magnetic nerve stimulating probe used for triggered electromyography (t-EMG) to avoid these. This study aimed to investigate the efficacy of this probe for intraoperative neuromonitoring (ION) during lumbar pedicle screw placement in a porcine model. Forty pedicle screws were inserted bilaterally into the pedicles of the fourth and fifth lumbar vertebrae of five pigs; 20 were inserted typically into the pedicle without nerve damage (Group A), and the other 20 were inserted through the broken medial wall of the pedicle to permit contact with the neural structures (Group B). We measured the triggered threshold for pedicle screw placement through the conventional nerve probe and our newly developed magnetic probe. There was no significant difference in the triggered threshold between the two instruments (p = 0.828). Our newly developed magnetic stimulating probe can be attached to a screwdriver, thus preventing real-time screw malpositioning and making it practical and equally safe. This probe could become indispensable in revision spine surgeries with severe adhesions or endoscopic spine surgeries. Full article
(This article belongs to the Special Issue Recent Developments and Emerging Trends in Biomechanics)
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20 pages, 960 KiB  
Review
Symmetry and Quantum Features in Optical Vortices
by David L. Andrews
Symmetry 2021, 13(8), 1368; https://doi.org/10.3390/sym13081368 - 28 Jul 2021
Cited by 25 | Viewed by 4359
Abstract
Optical vortices are beams of laser light with screw symmetry in their wavefront. With a corresponding azimuthal dependence in optical phase, they convey orbital angular momentum, and their methods of production and applications have become one of the most rapidly accelerating areas in [...] Read more.
Optical vortices are beams of laser light with screw symmetry in their wavefront. With a corresponding azimuthal dependence in optical phase, they convey orbital angular momentum, and their methods of production and applications have become one of the most rapidly accelerating areas in optical physics and technology. It has been established that the quantum nature of electromagnetic radiation extends to properties conveyed by each individual photon in such beams. It is therefore of interest to identify and characterize the symmetry aspects of the quantized fields of vortex radiation that relate to the beam and become manifest in its interactions with matter. Chirality is a prominent example of one such aspect; many other facets also invite attention. Fundamental CPT symmetry is satisfied throughout the field of optics, and it plays significantly into manifestations of chirality where spatial parity is broken; duality symmetry between electric and magnetic fields is also involved in the detailed representation. From more specific considerations of spatial inversion, amongst which it emerges that the topological charge has the character of a pseudoscalar, other elements of spatial symmetry, beyond simple parity inversion, prove to repay additional scrutiny. A photon-based perspective on these features enables regard to be given to the salient quantum operators, paying heed to quantum uncertainty limits of observables. The analysis supports a persistence in features of significance for the material interactions of vortex beams, which may indicate further scope for suitably tailored experimental design. Full article
(This article belongs to the Section Physics)
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16 pages, 17146 KiB  
Article
Fracture Analysis of High-Strength Screw for Highway Construction
by Andrej Dubec, Petra Kováčiková, Jan Krmela, Vladimíra Krmelová and Artem Artyukhov
Materials 2021, 14(7), 1599; https://doi.org/10.3390/ma14071599 - 25 Mar 2021
Cited by 4 | Viewed by 2608
Abstract
High-strength screws represent one of the main joining or fastening components which are commonly used in the process of installation of frame constructions for information boards or signposts, relating to the traffic roads. The control of the production process may not always be [...] Read more.
High-strength screws represent one of the main joining or fastening components which are commonly used in the process of installation of frame constructions for information boards or signposts, relating to the traffic roads. The control of the production process may not always be a sufficient method for ensuring road safety. The backward investigation and control of the screw material processing seems to be the one of the most important procedures when there is the occurrence of any failure during the operation of the screw. This paper is mainly focused on the analysis of the failure of the high-strength screw of 10.9 grade with M diameter of 27 × 3 and a shank length of 64 mm. The mentioned and investigated screw was used as a fastener in a highway frame construction. In the paper, there is mainly the analysis of the material for a broken screw in terms of the material micropurity, the material microstructure, the surface treatment as well as chemical composition. The evaluation was based on investigation by optical microscopy, scanning electron microscopy and energy dispersive spectroscopy. Important knowledge and results were also obtained due to information on micromorphology and material contrast of the fracture surface resulting from fractographic analysis, using the method of scanning electron microscopy. In the case of the production of the high-strength screws, the tempering stands for the decisive or crucial process of heat treatment because the given process can ensure a decrease in hardness, while the required ductile properties of the material are kept and this is also reflected in the increase of strength and micromorphology of the fracture surface. From the aspect of micropurity, inclusions of critical size or distribution were not identified in the material, referring to Czech standard ČSN ISO 4967 (420471). The microstructure corresponds to tempered martensite, but the fracture surface of the broken screw was based on an intercrystalline micromechanism, which is undesirable for the given type of component. Combined with the measurement of the HV1 (Vickers hardness at a load of 1 kg) from the edge to the central area of the screw, the analysis revealed the significant drawbacks in the heat treatment of the high-strength screw. Full article
(This article belongs to the Special Issue Manufacturing and Fatigue Properties of Materials)
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4 pages, 114 KiB  
Case Report
Retained Broken Implants in the Craniomaxillofacial Skeleton
by Vigneswaran Nallathamby, Hanjing Lee, Yap Yan Lin, Jane Lim, Wei Chen Ong and Thiam-Chye Lim
Craniomaxillofac. Trauma Reconstr. 2014, 7(2), 154-157; https://doi.org/10.1055/s-0034-1371551 - 11 Mar 2014
Viewed by 79
Abstract
Facial fracture patients are seen in a Level 1 trauma hospital. In our institution, we manage many patients with facial fractures and carry out more than 150 surgical procedures every year. Open reduction and internal fixation is our management of choice. All surgical [...] Read more.
Facial fracture patients are seen in a Level 1 trauma hospital. In our institution, we manage many patients with facial fractures and carry out more than 150 surgical procedures every year. Open reduction and internal fixation is our management of choice. All surgical procedures involve drilling of bone and implant insertion to keep the fractured bones in an anatomically reduced position to aid healing. Occasionally, drill bits used to create the pilot hole break and are embedded in the bone. We present a situation in which such an incident occurred and review the literature on retained broken implants and devices. Full article
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