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Purpose: In an MRI system, the static magnetic field homogeneity is strictly required especially in ultrahigh field situations. However, owing to the engineering tolerances and system errors, the magnetic field homogeneity of a magnet usually cannot meet the imaging requirement; thus, a shimming operation is always needed. Methods: Existing passive shimming methods commonly minimize the peak‐peak variations of the magnetic fields over the diameter of spherical volume (DSV), targeting the field quality of 10–20 parts per million (ppm). However, these conventional passive shimming methods can sometimes lead to sub‐optimal field quality and iron consumption solutions. Notably, the RMS error (RMSE) value of the field uniformity is inherently unoptimized. This work proposed a novel passive shimming method that can deliver a significantly improved shimming solution by actively controlling the central magnetic field and specific magnetic field deviations in the region of interest. A detailed comparison between the conventional and proposed methods was conducted on a 9.4T human MRI superconducting magnet. Results: The results showed that the new solution had a significant advantage in searching for superior magnetic field homogeneity with less iron piece consumption. Significantly, the RMSE value of the magnetic field over the DSV can be substantially reduced >10 times. The proposed algorithms are also very efficient, taking only several seconds to find the shimming solution. Conclusion: The potential of the magnetic field homogeneity improvement methods will promote the development of high‐end MRI systems. [ABSTRACT FROM AUTHOR]

This article describes a method for detecting hidden nitrogen-containing substances. A description is given of a mobile complex based on a linear electron accelerator (LAE) capable of solving problems of detecting nitrogen-containing substances. The block diagram of the mobile complex is given and the accelerating system used for particle acceleration is described. The rotation of the electron beam is carried out using a special electromagnet located on the beam flight path. A drawing of such an electromagnet is given. The linear accelerator is placed in a container 6 m in length. The results of this work are of undoubted interest in solving problems related to detecting nitrogen-containing substances. [ABSTRACT FROM AUTHOR]

ND-GAr is one of three detector systems in the design of the DUNE Near Detector complex, which will be located on the Fermilab campus, sixty meters underground and 570 m from the source of an intense neutrino beam. ND-GAr will consist of a cylindrical 10-bar gaseous Argon Time Projection Chamber (TPC) and a surrounding sampling electromagnetic calorimeter embedded within a superconducting solenoid, the cryostat and yoke for which together serve as the pressure vessel. While various options for the specific configuration of ND-GAr are being explored, essential design work for the detector has moved forward in recent months. This document describes basic mechanical, electrostatic, and gas flow design features of the ND-GAr TPC and presents results of electrostatic simulations of the interior of the pressure vessel for both single and dual-anode arrangements. Simulations are implemented with the Elmer finite-element software suite and related programs.

Artikel ini bertujuan untuk mendiskusikan tentang magnet barium ferit dan potensi penggunaannya sebagai material anti radar dalam teknologi siluman di Indonesia. Studi ini menggunakan berbagai macam literatur dan hasil penelitian terbaru. Teknologi siluman dikembangkan melalui penciptaan zat anti radar yang mampu menyerap sinyal radar yang dikenal dengan radar absorbing material. Berdasarkan hasil studi literatur didapatkan informasi bahwa magnet berbasis barium ferit berpotensi menjadi bahan baku penyerap gelombang radar karena dapat menyerap gelombang mikro, termasuk frekuensi gelombang yang digunakan pada radar. Karakteristik magnet dan kemampuan magnet barium ferit untuk menyerap gelombang radar dipengaruhi oleh berbagai kondisi, termasuk bahan kimia dan komponen organik. Magnet barium ferit telah digunakan sebagai bahan anti radar di militer, di kapal, pesawat, kendaraan darat, dan pakaian. Potensi barium ferit sebagai penggerak teknologi militer modern di Indonesia cukup besar namun masih terbatas dalam penelitian laboratorium. Sebagai usaha dalam penguasaan teknologi siluman, pemerintah Indonesia dapat menerapkan strategi dual-use technology dan model inovasi triple helix.

. “Sticking” and vibrations of the stator of permanent magnet generators cause their increased wear, noise; also, their operation efficiency decreases. The article theoretically considers the possibility of eliminating the starting torque and oscillation of the rotation torque of the generator with permanent magnets without load due to mutual compensation of the interaction of coils with the field of permanent magnets at a certain symmetry of this field. The mentioned pheno-menon is called pi-resonance. For the specified class of model interaction potentials of the field of permanent magnets and coils, it has been shown that full compensation occurs with a certain number of coils (Ns) and magnets (Nr), while for other combinations of {Ns, Nr} the interaction is in the nature of oscillations. The corresponding tables for various classes of potentials are given which can serve as a basis for making design decisions when developing generators. Pi-resonance more probably takes place in the case of even number of stator coils and odd number of magnets, as well as with an increase in the number of stator coils. The cases of both one-sided and two-sided arrangement of the stator relative to the rotor are considered. Numerical modelling has shown that the pi-resonance is easily destroyed if the placement of magnets or coils is inaccurate, as well as by the magnet field potential symmetry breaking. An error in the angular arrangement of the coils of 1° can result in the appearance of a significant “cogging” of the rotor with energy of the order of the interaction energy of an isolated magnet – coil pair. A distortion of the symmetry of the potential yields a result similar in scale which is equivalent to the adding of a rump function with the amplitude of 10 % of the amplitude of the symmetric periodic potential. The patterns that have been discovered can be used in the design of efficient generators with reduced level of noise and vibration.

BackgroundThe incidence of magnet ingestion by children has recently increased in China. Magnet ingestion is associated with an extremely high risk of gastrointestinal damage because loops of bowel can become trapped and squeezed between multiple magnets in different locations. However, the lack of imaging sensitivity makes clinical decision-making difficult.ObjectiveThis study was conducted to investigate the performance of ultrasound in diagnosing gastrointestinal magnet ingestion in children.MethodsFrom April 2017 to February 2021, all children with a history of magnet ingestion or a diagnosis of gastrointestinal magnet as shown by x-ray or ultrasound in our hospital were included as study candidates. Patients who were lost to follow-up or had known malformations of the gastrointestinal tract were excluded. Eligible patients were those with surgical or endoscopic confirmation of gastrointestinal magnet, those who passed the magnet out of the alimentary tract without assistance, and those with confirmed absence of the magnet on abdominal x-ray examination after 1 month of conservative treatment. All eligible patients' ultrasound and x-ray examination data were evaluated. The sensitivity, specificity, and area under the curve (AUC) of ultrasound was calculated for diagnosing magnet ingestion, locating the magnet (stomach, small intestine, or colon), and confirming the phenomenon of wall entrapment.ResultsOf 112 patients, 107 had a magnetic foreign body and 5 did not. Magnets were correctly detected by ultrasound in 97 patients, with an observed sensitivity of 90.65% and specificity of 100%. Satisfactory sensitivity was obtained for ultrasound localization of gastric magnets (96.30%) and small intestinal magnets (100.00%), but sensitivity for ultrasound localization of colonic magnets was relatively poor (73.33%). The discrimination of wall entrapment by ultrasound was good (AUC = 0.93), with an observed sensitivity and specificity of 92.00% and 93.62%, respectively.ConclusionsUltrasound can be used to locate gastrointestinal magnets (in the stomach, small intestine, or colon) with good clinical efficacy in identifying wall entrapment.

In this work, we develop a compact, low-power and partially 3D-printed magnetorheological fluid clutch that operates by variably and reversibly altering the shear stress of the fluid through the local activation of an array of electropermanent magnets (EPMs). By toggling the magnetization of each EPM independently on the order of a few milliseconds, we allow for rapid response times and variable torque transmission without further power input. Selectively polarizing the EPMs for different lengths of time results in repeatable and variable magnetic flux, in turn enabling further control precision. We present the design, modeling, and measured performance of this clutch with various control strategies, and demonstrate its utility as a low-power alternative to more traditional clutch designs.

The accuracy and enrichment rate of targeted drugs largely determine the clinical diagnosis and treatment effect. Therefore, the accuracy and enrichment rate of targeted drugs should be improved. We designed a visual diagnosis and treatment system based on hierarchical targeting. It consists of multifunctional magnetic nanoparticles and a bio magnetic material. Bio-magnet mediated primary targeting can effectively improve the drug enrichment rate in the target tissue. SNF peptide/epithelial cell adhesion molecule antibody mediated targeting liver cancer stem cells (LCSCs) (secondary target) can improve the accuracy of the treatment and its outcomes. Low intensity focused ultrasound irradiation can explode nanoparticles around LCSCs, which can cause physical damage to cells. The combination of released interferon gamma and its receptor (tertiary target) can be used to initiate chemotherapy and immunotherapy. Using the optical properties of Fe3O4 and the phase transformation ability of perfluoropentane, the system can enhance photoacoustic and ultrasonic molecular imaging enabling diagnosis and treatment visualization. Targeting LCSCs can accurately provide physical, chemical, and immune treatment of Hepatocellular carcinoma, making the therapeutic effect more effective and thorough. This system may provide a new method for a more accurate visual diagnosis and treatment of tumors.

Objective: Due to evidence for proton beam therapy (PBT) in pediatric central nervous system (CNS) tumors, compact proton therapy systems became commercially available to allow better integration in a hospital setting. However, these systems have a non-zero magnetic field at the level of the patient. Often, these patients have a cerebrospinal fluid shunt, and most of them are adjustable through a magnet. Whether the induced magnetic fields could interfere with adjustable shunts is unknown. Methods: In the first five CNS tumor patients with adjustable shunts who underwent PBT, the shunt setting was controlled before, during, and after treatment with PBT. Additionally, we used an ex vivo adjustable shunt to check if the settings could be altered by the magnetic field. Results: We did not observe unintentional changes in shunt settings in vivo during treatment. In ex vivo testing, the shunt settings were altered directly cranial to the exit window of PBT due to the magnetic field. Conclusion: Although we did not observe any shunt setting alteration during PBT in this small cohort, caution is warranted. Given the lack of high-volume data, there should be a low threshold for checking the shunt setting at the end of PBT therapy or in a symptomatic patient. [ABSTRACT FROM AUTHOR]

We developed an articulated mobile robot that can move on the magnetic curved walls and traverse through obstacles for wall surface inspections of a large tank. This robot is equipped with magnetic wheels and is able to stick to and move on steel wall. We add passive roll joints and turn off the torque of the pitch joints to ensure the wheels keep in contact with the curved surface. The developed robot is tested through experiments in the laboratory and also in a field test at the World Robot Summit 2020. The experiments are conducted to confirm the movements of the robot on the curved wall surface and when the units are lifted for obstacle traversal. As the results, the robot is not able to overcome an obstacle near the wall such as a handrail but is able to move freely on the curved wall surface and traverse some obstacles on the corner. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study is to synthesize available literature describing the development, implementation and evaluation of a Professional Practice Model. Background: A Professional Practice Model is an overarching theory‐based framework that depicts nursing values and defines the structure and process of nursing care. No research has synthesized available literature on this topic in recent times. Evaluation: A review of English language papers was published from 2015 to 2022. Fourteen studies met the inclusion criteria. Key Issues: All studies highlighted the importance of having a Professional Practice Model that reflects nursing care activities and resonates with nurses across an organization. This is achieved through strong leadership and clinical nurse involvement during the development, implementation and evaluation phases. In addition, a model should be adapted to keep up to date with scientific changes relevant to nursing. Conclusions: This review adds to the body of knowledge on the development, implementation and evaluation of a Professional Practice Model. Future research exploring the benefit of a Professional Practice Model on patient outcomes would be useful. Implications for nursing management: The key elements of a Professional Practice Model including six components and theoretical foundation have been summarized in this review. Nurse leaders should consider these key elements in the creation of a Professional Practice Model. For successful enculturation, a Professional Practice Model needs to be relevant to all nurses and easy for them to articulate. [ABSTRACT FROM AUTHOR]

Linear switched-flux machines are a kind of permanent magnet machine with a passive ferromagnetic secondary. Therefore, they can achieve both a good performance and a low cost in long stroke applications. However, due to the end effect, these machines generate high detent force and on load thrust force ripples. There are several solutions in the literature that aim to minimise the thrust ripple. One of those solutions is the placement of additional poles in the ends of the machine. These can be passive, i. e. simple ferromagnetic teeth, or active, with additional magnets. The former is the most common solution in the literature. In this article, the optimal configuration of the additional poles is discussed via 4 additional pole sizing strategies, and the influence of the design variables and optimisation objectives is analysed. Then, a generic additional pole configuration is proposed, which combines a high effectiveness and a simple design. Finally, an experimental validation is carried out, and the measurements confirm the results from the optimisation. [ABSTRACT FROM AUTHOR]

This article presents the main data on the grouting activities and trial research works for the optimization of the collar columns during the repeated grouting operations, which employ the collar technology in noncohesive soils when leveling the Zagorskaya PSP-2. [ABSTRACT FROM AUTHOR]

In the pediatric surgical environment, we can enrich our knowledge and improve our skills through interdisciplinary knowledge transfer in exchange with other surgical or even non-surgical disciplines. To demonstrate this, we present in this article three patient cases of method transfer enabling new techniques in minimally invasive pediatric surgery. 1. The somewhat modified application of the AeroStat rigid tip laparoscopic cholangiography catheter during the single-step laparoscopic cholecystectomy facilitates the safe intraoperative cholangiography with common bile duct flushing. 2. A magnetic rod is used during laparoscopic enterotomy to locate and retrieve ingested magnets. 3. Using a patient-specific MRI 3D model representing a syndromic high anorectal malformation improves surgical planning and parental education. [ABSTRACT FROM AUTHOR]

The formalism of composite and intertwined orders has been remarkably successful in discussing the complex phase diagrams of strongly correlated materials and high- T c superconductors. Here, we propose that composite orders are also realized in ferroelectric and ferromagnetic materials when lattice anisotropy is taken into account. This composite order emerges above the ferroic phase transition, and its type is determined by the easy axis of magnetization or polarization, respectively. In multiferroic materials, where polarization and magnetization are coupled, composites of both orders are possible. This formalism of composite orders naturally accounts for magnetoelectric monopole, toroidal, and quadrupole orders. More broadly, composite orders may explain precursor phenomena in incipient ferroic materials, arising at temperatures above the ferroic phase transition and potentially contributing to the characterization of currently hidden orders., (Creative Commons Attribution license.)

Background: Removal of orbital foreign bodies is a surgical challenge. The purpose of this study is to report our experience in the removal of orbital foreign bodies and to evaluate the usefulness of various technological aids in their removal., Materials and Methods: We conducted a single-center retrospective study at Nice University Hospital (France) from January 2017 to December 2023. All patients undergoing surgery for an orbital foreign body during the study period were included. Data recorded included the nature of the orbital foreign body, its size, location, surgical route, outcome (success, partial success, failure), and technological aids used (intraoperative navigation, intraoperative imaging scope, orbital magnet). Concurrently, we designed a dedicated orbital magnet, which was tested in the anatomy laboratory and in two of our patients., Results: Six patients, all young men, were included during the study period. Removal was successful, partially successful, or unsuccessful in one-third of cases, respectively. Failure was associated with orbital foreign bodies located in the intraconal or posterior orbital space. Preoperatively, the use of a "low-artifact" scanner allowed us to better determine the exact size and shape of the orbital foreign body. Intraoperative navigation was not accurate enough, due to the mobility of the orbital bodies within the orbital fat. In our experience, intraoperative scope imaging was more accurate. The use of a dedicated orbital magnet was successfully tested in the anatomy laboratory and allowed the removal of a small orbital foreign body in one of our patients. Intraoperative surgical videos are provided., Conclusion: Vegetal orbital foreign bodies must be systematically removed. Removal of non-vegetal orbital foreign bodies should be considered on a case-by-case basis based on their size, best assessed using a "low artifact" scanner, their location, and their intrinsic ferromagnetism. Intraoperative navigation does not appear useful, while intraoperative scope imaging does. A dedicated orbital magnet might be helpful in removing ferromagnetic orbital foreign bodies. However, an orbital magnet may be ineffective in removing intraorbital bullets, since they are made primarily of an alloy of copper and lead., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

We present a case where ingestion of multiple bead magnets caused multiple perforations of small bowel and required surgical intervention. Pressure necrosis of intervening loops of small intestine led to tiny perforations at multiple sites without contamination of the abdomen. All of those magnets were retrieved by performing enterotomy and resection & anastomosis done at few sites. If unattended or missed out they can even lead to death. [ABSTRACT FROM AUTHOR]

The current study uses the finite element technique to investigate a single-phase induction motor with non-uniform stator slots. A 0.5 hp, four poles, 36 stator slots, and 48 rotor slots have non-uniform stator slots was analyzed based on magnet Finite Element Method software with using AutoCAD in modeling stator due to its unsymmetrical slots, The suggested study attempts to evaluate all motor design modifications. The values of currents and torque received from the FEM analysis for test motor were compared with motor nameplate data with a good agreement. [ABSTRACT FROM AUTHOR]

ND-GAr is one of three detector systems in the design of the DUNE Near Detector complex, which will be located on the Fermilab campus, sixty meters underground and 570 m from the source of an intense neutrino beam. ND-GAr will consist of a cylindrical 10-bar gaseous Argon Time Projection Chamber (TPC) and a surrounding sampling electromagnetic calorimeter embedded within a superconducting solenoid, the cryostat and yoke for which together serve as the pressure vessel. While various options for the specific configuration of ND-GAr are being explored, essential design work for the detector has moved forward in recent months. This document describes basic mechanical, electrostatic, and gas flow design features of the ND-GAr TPC and presents results of electrostatic simulations of the interior of the pressure vessel for both single and dual-anode arrangements. Simulations are implemented with the Elmer finite-element software suite and related programs. [ABSTRACT FROM AUTHOR]

This project is the implementation of a hybrid configuration of wind mill for power generation purpose. Uses the effects of magnetic repulsion, unique shaped blades have been introduced with magnets attached to it providing an additional force to assist the wind turbines to generate electricity even without the need of wind energy. These wind turbines have advantage over conventional wind turbines because of factors such as contours of the land; often face either inadequate wind or turbulent winds. Moreover it can also be incorporated as a conventional windmill which will operate under sufficient wind energy and when the wind speed falls below the threshold level it can tap into self-revolving and would generate electricity using magnetic attraction and repulsion between the magnets placed on the blades and the electromagnet present on the pole of the wind mill. [ABSTRACT FROM AUTHOR]

The experiment was conducted to evaluate the production performance and egg quality of laying hens supplemented with phytobiotics and magnetized drinking water. This experiment used 2700 gauss level in Magnetized Drinking Water (MDW). The phytobiotics had two form: the non-encapsulated phytobiotics (PTO) and encapsulated phytobiotics (EPTO). There were untreated water (control) and the treated water (MDW, PTO, PTO+MDW, EPTO, EPTO+MDW). The treatments were presented by 0.6% for each treatment. The result showed highly significant (p

PurposeThe Magnetic Mini-Mover Procedure (3MP) is a minimally invasive treatment for prepubertal patients with pectus excavatum. This multicenter trial sought to supplement safety and efficacy data from an earlier pilot trial.MethodsFifteen patients with pectus excavatum had a titanium-enclosed magnet implanted on the sternum. Externally, patients wore a custom-fitted magnetic brace. Patients were monitored closely for safety. Efficacy was determined by the Haller Index (HI) and satisfaction surveys. After 2 years, the implant was removed.ResultsMean patient age was 12 years (range 8-14), and mean pretreatment HI was 4.7 (range 3.6-7.4). The device was successfully implanted in all patients. Mean treatment duration was 25 months (range 18-33). Posttreatment chest imaging in 13 patients indicated that HI decreased in 5, remained stable in 2, and increased in 6. Seven out of 15 patients had breakage of the implant's titanium cables because of fatigue fracture. Eight out of 13 patients were satisfied with their chest after treatment.ConclusionThe 3MP is a safe, minimally invasive, outpatient treatment for prepubertal patients with pectus excavatum. However, the magnetic implant design led to frequent device breakage, confounding analysis. The HI indicated mixed efficacy, although surveys indicated most patients perceived a benefit.Study type/level of evidenceCase series, treatment study. Level IV.

A four-layer canted-cosine-theta 16-T dipole has been designed as a possible candidate for future hadron colliders. The design maintains part of the future-circular-collider magnet requirements, i.e., a 50 mm clear bore and 16 T operating at 1.9 K. The magnet intercepts Lorentz forces with an internal structure of ribs and spars, minimizes conductor, and reduces the number of layers and magnet size by using wide cables. The role of iron and its impact on field and magnet size is discussed. A three-dimensional magnetic analysis was carried out for 1-in-1 and 2-in-1 designs including a structural analysis for the 1-in-1 case. Thoughts on future improvements during winding are also discussed.

Mechanical energy from vibrations is widespread in the ambient environment. It may be harvested efficiently using triboelectric generators. Nevertheless, a harvester’s effectiveness is restricted because of the limited bandwidth. To this end, this paper presents a comprehensive theoretical and experimental investigation of a variable frequency energy harvester, which integrates a vibro-impact triboelectric-based harvester and magnetic nonlinearity to increase the operation bandwidth and improve the efficiency of conventional triboelectric harvesters. A cantilever beam with a tip magnet was aligned with another fixed magnet at the same polarity to induce a nonlinear magnetic repulsive force. A triboelectric harvester was integrated into the system by utilizing the lower surface of the tip magnet to serve as the top electrode of the harvester, while the bottom electrode with an attached polydimethylsiloxane insulator was placed underneath. Numerical simulations were performed to examine the impact of the potential wells formed by the magnets. The structure’s static and dynamic behaviors at varying excitation levels, separation distance, and surface charge density are all discussed. In order to develop a variable frequency system with a wide bandwidth, the system’s natural frequency varies by changing the distance between the two magnets to reduce or magnify the magnetic force to achieve monostable or bistable oscillations. When the system is excited by vibrations, the beams vibrate, which causes an impact between the triboelectric layers. An alternating electrical signal is generated from a periodic contact-separation motion between the harvester’s electrodes. Our theoretical findings were experimentally validated. The findings of this study have the potential to pave the way for the development of an effective energy harvester that is capable of scavenging energy from ambient vibrations across a broad range of excitation frequencies. The frequency bandwidth was found to increase by 120% at threshold distance compared to the conventional energy harvester. Nonlinear impact-driven triboelectric energy harvesters can effectively broaden the operational frequency bandwidth and enhance the harvested energy.

Energy harvesting effectively powers micro-sensors and wireless applications. However, higher frequency oscillations do not overlap with ambient vibrations, and low power can be harvested. This paper utilizes vibro-impact triboelectric energy harvesting for frequency up-conversion. Two magnetically coupled cantilever beams with low and high natural frequencies are used. The two beams have identical tip magnets at the same polarity. A triboelectric energy harvester is integrated with the high-frequency beam to generate an electrical signal via contact-separation impact motion between the triboelectric layers. An electrical signal is generated at the low-frequency beam range achieving frequency up-converter. The two degrees of freedom (2DOF) lumped-parameter model system is used to investigate the system’s dynamic behavior and the corresponding voltage signal. The static analysis of the system revealed a threshold distance of 15 mm that divides the system into monostable and bistable regimes. In the monostable and bistable regimes, softening and hardening behaviors were observed at low frequencies. Additionally, the threshold voltage generated was increased by 1117% in comparison with the monostable regime. The simulation findings were experimentally validated. The study demonstrates the potential of using triboelectric energy harvesting in frequency up-converting applications.

• End-of-life audio products are potential recycling sources for NdFEB magnets. • HPMS recycles audio products in a commercially viable time frame. • Hydrogen interactions with extracted magnets were fully analysed by IGA. • Recycled magnets, blended with NdH 3 , showed similar properties to the originals. The transition towards green and sustainable technologies has significantly increased the demand for a subset of raw materials known as critical elements. Rare earth elements with their main use in Neodymium-Iron-Boron magnets (NdFeB) play a key role in clean energy technologies including electric vehicles and wind turbine generators. They are also a key component in electronic devices including mobile phones, hard disk drives, and loudspeakers. Here, we build on previous knowledge of the recycling of NdFeB magnets from hard disk drives, using a hydrogen process called HPMS (Hydrogen Processing of Magnet Scrap). This study investigates a new scrap stream from loudspeakers, specifically from vehicles and flat-screen TVs. The extracted magnets from loudspeakers typically had grades of N30/N33 with relatively low coercivity values. The interactions of the extracted magnets with hydrogen were monitored by gravimetric and thermal analyses. The thermodynamics and kinetics of the hydrogenation reaction appear to differ significantly based on their chemical composition, chemical homogeneity, coating state, and surface condition of the magnets. Overall, the HPMS process was demonstrated to successfully produce demagnetised hydrogen decrepitated powder at room temperature under 2 bar of hydrogen, in a commercially viable timeframe (approx. 4 h). Zinc was found to be the dominant coating material which peeled away during the HPMS process. The zinc content of the NdFeB alloy powder could be reduced after the hydrogen decrepitation by sieving. The remaining level of zinc had no noticeable impact on the magnetic properties of the recycled magnets. The particle size of the recycled alloy powder could be reduced to below 7 µm by ball milling and knife milling but with an increase in the oxygen level, limiting its sintering ability. Sintered magnet from the recycled alloy powder demonstrated similar magnetic properties (Br: 1.06 T, H cJ : 1240 kA/m, and (BH) max : 220 kJ/m3) after blending with 5 wt% of NdH 3 , making vehicles and flat-screen TV speakers ideal sources for a recycled magnet. [ABSTRACT FROM AUTHOR]

The novel use of magnetic force to optimize modern surgical techniques originated in the 1970s. Since then, magnets have been utilized as an adjunct or alternative to a wide array of existing surgical procedures, ranging from gastrointestinal to vascular surgery. As the use of magnets in surgery continues to grow, the body of knowledge on magnetic surgical devices from preclinical development to clinical implementation has expanded significantly; however, the current magnetic surgical devices can be organized based on their core function: serving as a guidance system, creating a new connection, recreating a physiologic function, or utilization of an internal–external paired magnet system. The purpose of this article is to discuss the biomedical considerations during magnetic device development and review the current surgical applications of magnetic devices.

Recently, high-speed motors are receiving a lot of attention in the industrial field. When driving a motor at high speed, the advantages include high power density, high efficiency, and miniaturization. However, the disadvantages of the high-speed operation of motors are mechanical and structural safety. This is because the bearings used in high-speed motors require characteristics such as precision and low friction. There are two prominent types of bearings mainly used in high-speed motors: rolling bearings and magnetic bearings. A feature of rolling bearings is that they reduce frictional resistance by contacting points or lines between the shaft and the bearing. However, the disadvantages of rolling bearings are high mechanical friction losses due to the need for contact with the lubrication system. Maintenance costs are high. For this reason, a lot of research on bearings is being conducted to reduce the frictional loss of bearings and increase their efficiency and reliability. Bearings that are advantageous for high-speed operation are magnetic bearings that do not require lubricants, have no friction loss, and have low maintenance. However, magnetic bearings have disadvantages such as high cost and difficulty in miniaturization. In this paper, a stator with a separated teeth structure was used to compensate for these disadvantages. Using this, a model with miniaturization, light weight, and high manufacturability was proposed. The model name proposed in this study is called the STMB (separated teeth magnetic bearing). There are also disadvantages of the STMB model proposed in this paper. A model that compensates for this drawback is called the HSTMB (hybrid separated teeth magnetic bearing). The HSTMB reduces the weight by removing the back yoke of the stator and has advantages of a high filling rate and high productivity in the form of a module. As a result, high productivity, light weight, and high performance are possible when the HSTMB is applied, which was proven through FEA (finite element analysis).

In a large-area electron beam (EB) irradiation method, high energy density of EB with about 60 mm in diameter can be used for melting metal surface instantly. Surface roughness of mold steels with planar shape decreases in a short time by the large-area EB irradiation. However, it is difficult to smooth a bottom surface of high aspect ratio hole, since the EB tends to concentrate on the entrance edge and/or upper inside wall of hole, and the energy density of the EB may decrease on the bottom surface of hole. Then, the method for guiding the EB to the bottom surface of high aspect ratio hole is required. The EB may concentrate on the bottom surface by control of magnetic field near the workpiece with the magnet, since the EB tends to move spirally along the magnetic force lines. In this study, guiding the large-area EB on the bottom surface of high aspect ratio hole is proposed by setting the magnet under the workpiece in order to smooth the bottom surface. Magnetic force lines near the workpiece are calculated by using the electromagnetic field analysis, and the possibility of guiding the EB to the bottom surface of high aspect ratio hole is investigated. Experimental and analytical results clarified that the bottom surface of high aspect ratio hole can be smoothed by multi-step EB irradiation with moving the horizontal offset distance of magnet. [ABSTRACT FROM AUTHOR]

Purpose of Review: The risk of cardiac implantable electronic device (CIED) interference from cell phones was previously thought to be low based on older studies. Current generation of smartphones have incorporated more magnets for optimization of wireless charging, attachment of accessories, and convenience functionalities. These magnets have the potential to cause CIEDs to inadvertently revert into magnet mode. The purpose of this review is to summarize recent findings on smartphones and their accessories causing interference on CIEDs. Recent Findings: Recent reports have demonstrated that the iPhone 12 series and accessories have the capability to cause CIED magnetic interference. Summary: Current generation of smartphones, smartwatches, wireless headphones, and accessories have the potential to cause CIEDs to revert into magnet mode in both in vivo and ex vivo experiments. The risk of a clinically significant event is unlikely as long as the Food and Drug Administration (FDA) recommendations are followed; keeping smartphones and accessories at least six inches away from CIEDs. [ABSTRACT FROM AUTHOR]

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Long-term loss of teeth due to aging can cause loss of muscle tonicity of the face. This results in unesthetic appearance, functional impairment, and disturbed psychosocial life. Sunken cheek is one among the main findings of long-term edentulous patients. It can be managed with a conventional denture prosthesis. However, in some cases, additional support could also be required. Cheek plumper prosthesis manages the slumped appearance of cheeks by providing extra support. It restores the facial esthetics; thereby enhancing the self-esteem of the patient. This case report describes the management of patients with sunken cheeks and their esthetic rehabilitation by using maxillary cheek plumpers attached with stainless steel coated neodymium magnet and push-button attachments to the conventional complete denture.

This paper presents a research conducted as part of development of the graduation thesis entitled: "Hydraulic numerical analysis of groundwater in the left hinterland of the Mostar hydroelectric power plant dam", which was developed and successfully defended at the Faculty of Civil Engineering, University of Mostar in 2020. The Mostar hydroelectric power plant, in tandem with the Salakovac HPP, levels the flows in the downstream course of the Neretva River. In the area around the embankment and the diaphragm wall, there are indications of filtration deformations of soil, and development of dominant directions of groundwater flows. The paper examines the area of the left hinterland of the Mostar hydroelectric power plant dam in the MAGNET 4 WATER program, and compares the obtained results with the existing verified results from the DHI WASY FEFLOW program as well as the field results. It was concluded that the spatial model is suitable for further research and analyses, e.g. for monitoring groundwater flows in the area, and for the analysis of risks of contaminant transport underground the left hinterland of HPP Mostar.

In this paper we summarize the evolution and contributions of superconducting magnets to particle accelerators as chronicled over the last 50 years of Particle Accelerator Conferences (PAC, NA-PAC and IPAC). We begin with an historical overview based primarily on PAC Proceedings augmented with references to key milestones in the development of superconducting magnets for particle accelerators. We then provide some illustrative examples of applications that have occurred over the past 50 years, focusing on those that have either been realized in practice or provided technical development for other projects, with discussion of possible future applications.