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ObjectivesTo evaluate the effectiveness of triamcinolone injections in treating external magnet displacement in cochlear implant (CI) patients with adhesions problems of their processor.PatientsWe present seven CI patients with magnet adhesion issues who presented to our tertiary care neurotology clinic. None of the patients had a history of head trauma, postimplant MRI, or surgery in the head and neck other than the cochlear implantation.InterventionTriamcinolone 40 mg/mL injected subcutaneously at the CI magnet site.Main outcome measureReduction of scalp thickness and successful magnet retention.ResultsOur cohort consisted of seven patients (eight implant sites) of which five were overweight or obese. The temporoparietal scalp thickness measured on preoperative CT scans varied between 8.4 and 15.9 mm. Initial conservative measures such as hair shaving at the magnet site, using a headband, and increasing magnet strength failed in all patients. After receiving triamcinolone injections at the CI receiver site, six out of seven patients (seven out of eight CI sites) were able to use their processor again without the need for a headband for an average of 9.55 hours/day. The average number of injections required for each patient was 2.57 (SD = 2.18), median (range) = 1 (1-7). One patient required a flap thinning surgery but showed no improvement even after flap thinning. None of the patients showed skin irritation, breakdown, ulceration, necrosis, or magnet exposure during follow-up period.ConclusionsThe significant improvement in CI retention shows that triamcinolone injections are effective in making the subcutaneous tissue thinner and allowing magnet retention.

Mandibular dentures are considered dubious in terms of retention in resorbed ridges. Implant bearing overdentures can be a solution to the abovesaid issue. Various attachments in use offer variations in retention and maintenance. The aim was to assess long term durability and retention of implant supported overdenture attachments. Two implant bearing overdentures were placed in 20 patients. Magnet and ball attachment were used and dentures were evaluated over a period of three years at different time intervals. Difference of attachments’ performance between intervals was assessed with ANOVA test and Tukey HSD post hoc test and the level of significance was set at p˂0.05. There was a decline in retention throughout research period in both categories; the ball and socket batch showed statistically significant (P˂0.05) better retention force compared to that of magnet group. There was lesser decline in mean retention force of 10.97N±0.82 to 7.24N±0.903 from one month to three years in magnet attachment retained overdentures. Ball attachments offer better retentive forces than magnet category. Magnet bearing overdentures offer more durability in terms of retention. [ABSTRACT FROM AUTHOR]

Integrating magnetic materials into dentistry has emerged as a promising advance for addressing diverse dental conditions. Magnetic particles comprising a magnetic core encapsulated within a biocompatible coating offer precise manipulation through external magnetic fields, rendering them invaluable in targeted drug delivery, magnetic resonance imaging, hyperthermia therapy, and diagnostic assays. Their tunable properties allow optimization for specific applications, enhancing therapeutic efficacy while minimizing off-target effects. Additionally, pre-adjust magnets showcase exceptional magnetic field strength and energy density. Their utilization in dental implants and orthodontic treatments facilitates tissue engineering and tooth movement, augmenting clinical outcomes and patient comfort. This review synthesizes current research directions and clinical applications of magnetic materials in dentistry, offering insights into their potential to transform dental healthcare and enhance patient well-being. [ABSTRACT FROM AUTHOR]

Despite the spread of novel-generation cochlear-implant (CI) magnetic systems, access to magnetic resonance imaging (MRI) for CI recipients is still limited due to safety concerns. The aim of this study is to assess and record the experiences of Hires Ultra 3D (Advanced Bionics) recipients who underwent an MRI examination. A multicentric European survey about this topic was conducted focusing on safety issues, and the results were compared with the current literature. We collected a total of 65 MRI scans performed in 9 otologic referral centers for a total of 47 Hires Ultra 3D recipients, including, for the first time, 2 children and 3 teenagers. Preventive measures were represented by scanning time and sedation for children. Head wrapping was used in eight cases, and six of the eight cases received local anesthesia, even if both measures were not needed. Only three patients complained of pain (3/65 examinations, 4.6%) due to the tight head bandage, and one of the three cases required MRI scan interruption. No other adverse events were reported. We believe that these results should encourage MRI execution in accordance with manufacturer recommendations for Ultra 3D recipients. [ABSTRACT FROM AUTHOR]

This paper presents a study on a push-down electromagnetic levitation system designed for suspending an object, counteracting gravity. The object is embedded with a magnet that allows its support using the electromagnetic levitation system. It involves a coupled electromagnetic field problem with a mechanical problem. Improving the levitation force and increasing the distance between the emitter and reflector are necessary for the correct positioning of the object. This paper proposes the use of a standing wave levitator to suspend and maintain a certain distance for an object using the electromagnetic levitation state.

Abstract Obstructions encountered in biliary, gastrointestinal, and urinary tracts are increasing in number due to successful percutaneous and endoscopic organ-saving procedures. Although functional recovery is established to an extent, failure of traversing an obstruction may end up necessitating invasive surgical procedures. Multidisciplinary collaboration may traverse the limitations of each individual approach, therefore creating the perfect intervention for the patient. Magnetic compression anastomosis is a minimally invasive procedure that can provide a great outcome in select cases with biliary, gastrointestinal, or urinary tract obstructions. Critical relevance statement In this article, various applications of magnetic compression anastomosis are reviewed with illustrative cases of esophageal, biliary, colonic, and urinary obstructions that cannot be traversed with a wire. This method will expand the spectrum of interventions performed in the IR unit. Key Points Magnets can enable wire access beyond an impassable obstruction. Magnets can create anatomical and non-anatomical anastomosis at an occlusion. Magnetic compression anastomosis is a minimally invasive procedure that can provide great outcomes. Graphical Abstract

Despite the spread of novel-generation cochlear-implant (CI) magnetic systems, access to magnetic resonance imaging (MRI) for CI recipients is still limited due to safety concerns. The aim of this study is to assess and record the experiences of Hires Ultra 3D (Advanced Bionics) recipients who underwent an MRI examination. A multicentric European survey about this topic was conducted focusing on safety issues, and the results were compared with the current literature. We collected a total of 65 MRI scans performed in 9 otologic referral centers for a total of 47 Hires Ultra 3D recipients, including, for the first time, 2 children and 3 teenagers. Preventive measures were represented by scanning time and sedation for children. Head wrapping was used in eight cases, and six of the eight cases received local anesthesia, even if both measures were not needed. Only three patients complained of pain (3/65 examinations, 4.6%) due to the tight head bandage, and one of the three cases required MRI scan interruption. No other adverse events were reported. We believe that these results should encourage MRI execution in accordance with manufacturer recommendations for Ultra 3D recipients.

Pada generator magnet permanen, semakin besar flux magnet akan semakin besar back-emf. Namun semakin tinggi flux magnet akan semakin tinggi rugi daya pada inti stator dan inti sehingga akan meningkatkan suhu kerja generator. Pada inti rotor, salah satu cara mengurangi rugi daya adalah dengan mengurangi volume rotor yang dialiri flux magnet. Studi ini membahas pengaruh penambahan lubang pada inti rotor terhadap flux magnet pada celah udara. Metode yang digunakan adalah simulasi magnetic menggunakan software FEMM 4.2. Simulasi diawali dengan kombinasi ketebalan magnet 1-5 mm dengan jarak antar magnet pada rotor 1 mm dan celah udara 3 mm untuk membuktikan relasi antara ketebalan magnet dan flux magnet di celah udara. Ketebalan magnet 5 mm dengan rapat fluks tertinggi kemudian dikombinasikan dengan penambahan lubang identik pada rotor sebanyak 1-8 buah. Flux magnet di celah udara diamati. Hasilnya : (i) semakin besar tebal magnet semakin tinggi flux magnet pada celah udara, (ii) penambahan lubang pada inti rotor tidak menurunkan flux magnet di celah udara, bahkan semakin banyak lubang identik pada inti stator cenderung meningkatkan nilai flux magnet di celah udara.

Abstract Background Budget constraints, staff shortages and high workloads pose challenges for German hospitals. Magnet® and Pathway® are concepts for implementing organization-wide change and redesigning work environments. There is limited research on the key elements that characterize nurse leaders driving the implementation of Magnet®/Pathway® principles outside the U.S. We explored the key attributes of nurse leaders driving organization-wide change through Magnet®/Pathway® principles in German hospitals. Methods Using a qualitative study design, semi-structured interviews (n = 18) were conducted with nurse leaders, managers, and clinicians, in five German hospitals known as having started implementing Magnet® or Pathway® principles. The interviews were recorded and transcribed verbatim. Data were analyzed in Atlas.ti using content analysis. For the analysis, a category system was created using a deductive-inductive approach. Results Five leadership attributes and eleven sub-attributes were identified as main themes and sub-themes: Visionary leaders who possess and communicate a strong vision and serve as role models to inspire change. Strategic leaders who focus on strategic planning and securing top management support. Supportive leaders who empower, emphasizing employee motivation, individualized support, and team collaboration. Stamina highlights courage, assertiveness, and resilience in the face of challenges. Finally, agility which addresses a leader’s presence, accessibility, and rapid responsiveness, fostering adaptability. Conclusions The study demonstrates leadership attributes explicitly focusing on instigating and driving organization-wide change through Magnet®/Pathway® principles in five German hospitals. The findings suggest a need for comprehensive preparation and ongoing development of nurse leaders aimed at establishing and sustaining a positive hospital work environment.

A dipole magnet generating 20 T and beyond will require high-temperature superconductors such as Bi2Sr2CaCu2O 8 − x and REBa2Cu3O 7 − x (RE = rare earth, rebco). Symmetric tape round (star®) wires based on rebco tapes are emerging as a potential conductor for such a magnet, demonstrating a whole-conductor current density of 580 A mm−2 at 20 T, 4.2 K, and at a bend radius of 15 mm. There are, however, few magnet developments using star® wires. Here we report a subscale canted cos θ dipole magnet as an initial experiment for two purposes: to evaluate the conductor performance in a magnet configuration and to start developing the magnet technology, leveraging the small bend radius afforded by star® wires. The magnet was wound with two star® wires, electrically in parallel and without transposition. We tested the magnet at 77 and 4.2 K. The magnet reached a peak current of 8.9 kA, 78% of the short-sample prediction at 4.2 K, and a whole-conductor current density of 1500 A mm−2. The experiment demonstrated a minimum viable concept for dipole magnet applications using star® wires. The results also allowed us to identify further development needs for star® conductors and associated magnet technology to enable high-field rebco magnets.

Obstructions encountered in biliary, gastrointestinal, and urinary tracts are increasing in number due to successful percutaneous and endoscopic organ-saving procedures. Although functional recovery is established to an extent, failure of traversing an obstruction may end up necessitating invasive surgical procedures. Multidisciplinary collaboration may traverse the limitations of each individual approach, therefore creating the perfect intervention for the patient. Magnetic compression anastomosis is a minimally invasive procedure that can provide a great outcome in select cases with biliary, gastrointestinal, or urinary tract obstructions. Critical relevance statement: In this article, various applications of magnetic compression anastomosis are reviewed with illustrative cases of esophageal, biliary, colonic, and urinary obstructions that cannot be traversed with a wire. This method will expand the spectrum of interventions performed in the IR unit. Key Points: Magnets can enable wire access beyond an impassable obstruction. Magnets can create anatomical and non-anatomical anastomosis at an occlusion. Magnetic compression anastomosis is a minimally invasive procedure that can provide great outcomes. [ABSTRACT FROM AUTHOR]

Background: Budget constraints, staff shortages and high workloads pose challenges for German hospitals. Magnet® and Pathway® are concepts for implementing organization-wide change and redesigning work environments. There is limited research on the key elements that characterize nurse leaders driving the implementation of Magnet®/Pathway® principles outside the U.S. We explored the key attributes of nurse leaders driving organization-wide change through Magnet®/Pathway® principles in German hospitals. Methods: Using a qualitative study design, semi-structured interviews (n = 18) were conducted with nurse leaders, managers, and clinicians, in five German hospitals known as having started implementing Magnet® or Pathway® principles. The interviews were recorded and transcribed verbatim. Data were analyzed in Atlas.ti using content analysis. For the analysis, a category system was created using a deductive-inductive approach. Results: Five leadership attributes and eleven sub-attributes were identified as main themes and sub-themes: Visionary leaders who possess and communicate a strong vision and serve as role models to inspire change. Strategic leaders who focus on strategic planning and securing top management support. Supportive leaders who empower, emphasizing employee motivation, individualized support, and team collaboration. Stamina highlights courage, assertiveness, and resilience in the face of challenges. Finally, agility which addresses a leader's presence, accessibility, and rapid responsiveness, fostering adaptability. Conclusions: The study demonstrates leadership attributes explicitly focusing on instigating and driving organization-wide change through Magnet®/Pathway® principles in five German hospitals. The findings suggest a need for comprehensive preparation and ongoing development of nurse leaders aimed at establishing and sustaining a positive hospital work environment. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate changes in owner-reported pain, interference of pain on function, and quality of life (QOL) in dogs with clinically suspected osteoarthritis when wearing a collar containing a static magnet. ANIMALS: 16 dogs over 5 years old weighing between 10 and 40 kg with a clinical diagnosis of osteoarthritis and on stable treatment. METHODS: A prospective, blinded crossover study in which dogs wore a collar containing a static magnet or placebo for two 4-week study arms separated by a 2-week washout period. Clients completed the Canine Brief Pain Inventory prior to collar placement and then weekly throughout each arm. Changes in QOL, pain severity, and pain interference scores from the beginning to the end of these arms and changes between the arms were calculated and analyzed using Wilcoxon signed rank tests. RESULTS: 40% of included dogs were on stable doses of NSAIDs. The pain severity scores (PSS), pain interference scores (PIS), and QOL scores were not significantly different at the start of the arms. There was no significant change in PSS or PIS from the start to end of the placebo arms (median changes, 0 and -0.1). Both PSS and PIS reduced significantly during the magnet arms (median changes, -1.0 and -1.2, respectively). The QOL scores did not change significantly in either arm (median changes, 0 and 0). CLINICAL RELEVANCE: This preliminary study suggests that magnetic collars reduce owner-reported pain severity and pain interference on function in dogs with clinically suspected osteoarthritis, and further, larger investigations are now warranted. [ABSTRACT FROM AUTHOR]

Mandibular dentures are considered dubious in terms of retention in resorbed ridges. Implant bearing overdentures can be a solution to the abovesaid issue. Various attachments in use offer variations in retention and maintenance. The aim was to assess long term durability and retention of implant supported overdenture attachments. Two implant bearing overdentures were placed in 20 patients. Magnet and ball attachment were used and dentures were evaluated over a period of three years at different time intervals. Difference of attachments’ performance between intervals was assessed with ANOVA test and Tukey HSD post hoc test and the level of significance was set at p

Salah satu alat pemanen energi alternatif adalah generator Winbelt. Winbelt adalah alat konversi energi yang mengubah gerakan angin menjadi energi listrik. Dalam generator Winbelt terdapat suatu alat induksi eletromagnetik yang terdiri dari magnet dan kumparan. Karena gerakan angin yang mengenai belt, sehingga menggerakan magnet secara bolak balik terhadap kumparan, maka terjadilah induksi elektromangnetis yang dapat menghasilkan listrik. Penelitian ini membahas pengaruh lebar Pita Winbelt terhadap energi listrik yang dihasilkan dengan variasi kecepatan angin yang diberikan. Metodologi penelitian melibatkan pembuatan beberapa prototipe Windbelt dengan panjang pita yang sama namun berbeda dalam hal tingkat kelebaran. Selanjutnya, prototipe tersebut ditempatkan dalam lingkungan yang dapat mensimulasikan angin atau aliran udara yang cukup untuk menghasilkan getaran pada pita. Tegangan listrik yang dihasilkan oleh setiap prototipe diamati dan diukur menggunakan perangkat pengukur yang sesuai. Setelah dilakukan pengukuran, didapatkan nilai tengangan listrik tertinggi dihasilkan pada variasi lebar Pita 18 mm dan dengan kecepatan angin 3.0 m/s sebesar 2,62 volt.

The machining of extremely hard material in conventional machining requires high energy. Therefore stress-free, burr-free, and high-accuracy machining technique like Electro Chemical Micro Machining (ECMM) with extra features is recommended. To improve efficiency, various electrolytes such as Magnet Associated Electrolytes (MGAE), Metal Particle Mixed Electrolytes (MPME), and Carbon Pellets Mixed Electrolytes (CPME) are employed. The micro-holes were drilled over the work material MONEL 400 alloy. The parameters for the studies are electrolyte type, concentration (g/l), machining voltage (V), and duty cycle (%). The responses of ECMM are estimated through material removal rate (MRR) in μm/sec and overcut in μm. The results are optimized using Multi-objective optimization based on ratio analysis (MOORA) and VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). Both techniques produce the same optimal parameter, 18th experiment CPME, 50% duty cycle, 11 V machining voltage, and 28 g/l electrolyte concentration. It is the best optimal parameter solution for machining. According to the ANOVA table of both, the type of electrolyte plays a 62.6% and 60.37% contribution, respectively, to machining performance. Furthermore, the scanning electron microscope (SEM) image analysis perused on the micro holes to extend the effect of different electrolytes on machining surfaces.

This article discusses the fabrication of a 25.2 T NMR magnet for an extreme condition user facility in China. The magnet is made using a combination of low-temperature superconducting (LTS) and high-temperature superconducting (HTS) materials. The use of HTS materials allows for higher field strengths and better signal-to-noise ratios in NMR experiments. The article also describes the challenges in winding solenoid coils with HTS materials and proposes a novel random ordering method to minimize inconsistencies. The fabricated magnet demonstrates excellent field stability and homogeneity, making it a useful tool for material science research and potentially expanding its application in medical imaging. [Extracted from the article]

AbstractThe authors carried out 1.5 T MRI examination without removing the CI magnet in two children with a cochlear implant (CI). In the first child, a conventional MRI scanning technique was used, which produced an image that was not clinically useful due to artifact size. He/she was scanned again using the ‘propeller technique’. This scan had a reduced artifact and was clinically useful. The second child was scanned using the propeller technique while asleep. The image was clinically useful. The authors conclude that the propeller technique is safe and of benefit to clinical diagnosis because it enables clinically useful images to be generated in a 1.5 T MRI without necessitating CI magnet removal and reimplantation surgeries.

In electrochemical machining, acids are extensively used as electrolytes to machine components. The use of acids to machine SS304 pollutes the environment and has a lot of safety issues. Hence, the use of environmentally friendly electrolytes is in high demand. NaCl is an eco-friendly electrolyte and is abundantly available at a lower price. The aim of this research is to propose a method to effectively use NaCl electrolyte to machine SS304. In this research, a novel method of machining using a dual fluid system has been adopted to machine SS304. A dual fluid system uses two fluids during the machining process. The anodic dissolution of the workpiece is done by the primary fluid system that uses NaCl, while the secondary system is used to supply fluids that prevent the removal of material from unwanted regions in the machining zone and also aid in the removal of by-products formed in the machining zone. The purpose of the secondary fluid system is to act as a resistance towards the removal of material from unwanted regions. In all the experimental conditions, NaCl was used as fluid in the primary fluid system. In the secondary fluid system, aqueous solution of NaCl, NaNO3, NaHCO3, C12H22O11, and distilled water was used. Moreover, the influence of magnet is also studied. It was observed that when machining was done under the influence of a magnet, a reduction of stray current intensity was observed when using NaCl in secondary fluid system, thereby contributing to less severe attach in the workpiece. The output responses were evaluated based on taper angle, radial overcut, MRR, surface roughness, and radial-stray current affected zone. The combination of the primary and secondary fluid systems in dual fluid system-assisted ECM (DF-ECM) is an advanced electrochemical machining (ECM) process, which offers several advantages, including better control over the machining process, improved surface finish, and reduced chances of pit formation at the entry side of the hole. [ABSTRACT FROM AUTHOR]

Damage to the central nervous system causes severe consequences for patients and increases medical costs. In spinal cord injuries, due to sensitive nerves, there is a need for a high-precision and non-invasive method to transfer macromolecules to the damaged area of the spinal cord for nerve repair. The main objective of this study is a high-impact strategy for optimal delivery of macromolecules to spinal cord injuries using ultrasound and magnetic fields. Several permanent magnets and transducers of ultrasound waves with different arrangements, sizes, and angles are used. Their effect on the efficiency of delivering macromolecules to the target area is analyzed. The results determined that utilizing three or four magnets along with the transducer of ultrasound waves could have a precise performance in the delivery of macromolecules. Advances in combining ultrasound and magnetic fields in delivering macromolecules to the target area are associated with increased efficiency and accuracy. The interaction between ultrasound and magnetic forces balances the rotation of macromolecules and their useful movement toward the destination. [ABSTRACT FROM AUTHOR]

The authors carried out 1.5 T MRI examination without removing the CI magnet in two children with a cochlear implant (CI). In the first child, a conventional MRI scanning technique was used, which produced an image that was not clinically useful due to artifact size. He/she was scanned again using the 'propeller technique'. This scan had a reduced artifact and was clinically useful. The second child was scanned using the propeller technique while asleep. The image was clinically useful. The authors conclude that the propeller technique is safe and of benefit to clinical diagnosis because it enables clinically useful images to be generated in a 1.5 T MRI without necessitating CI magnet removal and reimplantation surgeries. [ABSTRACT FROM AUTHOR]

The use of magnet compression to endoscopically create an esophageal anastomosis is an intriguing approach to esophageal atresia repair, but published cases with an existing available device have demonstrated mixed success. One major shortcoming has been the formation of subsequent severe, recalcitrant strictures after primary repair. To address the limitations of the existing device, we recently introduced and reported success with specially designed bi-radial magnets that exhibit a novel geometry and unique tissue compression profile. The aim of this study is to compare the outcomes using our novel device (novel group, NG) with those of previous reports which utilized the historical device (historic group, HG) in a PRISMA-compliant systematic review. Seven studies were eligible for further analysis. Additionally, one of our previously unreported cases was included in the analysis. Esophageal pouch approximation prior to primary repair was performed more frequently in the NG than in the HG (100% NG vs. 21% HG; p = 0.003). There was no difference in the overall postoperative appearance of postoperative stricture (95% HG vs. 100% NG; p = 0.64). The number of postoperative dilatations trended lower in the NG (mean 4.25 NG vs. 9.5 HG; p = 0.051). In summary, magnetic compression anastomosis adds a new promising treatment option for patients with complex esophageal atresia. Prior approximation of pouches and a novel magnet design have the potential to lower the rate of stricture formation.

Integrating magnetic materials into dentistry has emerged as a promising advance for addressing diverse dental conditions. Magnetic particles comprising a magnetic core encapsulated within a biocompatible coating offer precise manipulation through external magnetic fields, rendering them invaluable in targeted drug delivery, magnetic resonance imaging, hyperthermia therapy, and diagnostic assays. Their tunable properties allow optimization for specific applications, enhancing therapeutic efficacy while minimizing off-target effects. Additionally, pre-adjust magnets showcase exceptional magnetic field strength and energy density. Their utilization in dental implants and orthodontic treatments facilitates tissue engineering and tooth movement, augmenting clinical outcomes and patient comfort. This review synthesizes current research directions and clinical applications of magnetic materials in dentistry, offering insights into their potential to transform dental healthcare and enhance patient well-being.

A prototype of a type A quadrupole magnet has been designed and manufactured for the 3 GeV storage ring of Siam Photon Source II, the second synchrotron light source in Thailand. The required quadrupole gradient is 51 T/m with the magnet effective length being 162 mm. Magnet modeling and magnetic field calculation were performed using Radia and Opera-3D. The bore radius of the magnet is 16 mm. The magnet will be operated at the excitation of 5544 A-turns. A mechanical analysis of the magnet structure was performed in SOLIDWORKS and ANSYS, where the maximum deformation of 0.003 mm was found at the magnet poles, and the first-mode natural frequency was higher than 100 Hz. The magnet yoke is made of AISI 1006 low-carbon steel with a fabrication tolerance of ±0.020 mm. Magnet coils are water-cooled and made of high-purity copper. The temperature rise of the coils was below 3.0 °C at the maximum excitation of 6664 A-turns, which is 20% above the operating point. Magnetic field measurement was carried out using the Hall probe technique. The measured magnetic field and coil temperature of the prototype show good agreement with the calculations.

An electric dipole magnet quite similar to that of the IRANCYC10 cyclotron was designed and constructed to conduct the initial tests on the internal Penning ion source to be installed in the cyclotron. This magnet which was designed and constructed in the department of physics, University of Tehran, is capable of producing a magnetic field of 7000 G in the location of the source, a region in the center of the magnet with the radial extent of 15 mm, with no need for cooling. Magnetic fields as high as 1.1 T are also accessible for a few minutes. The ion source in IRANCYC10 is expected to be exposed by a magnetic field of 1100 G. The measurements show that the magnetic field in the location of the source is homogeneous with the maximum deviation value of 1.1% with respect to the magnetic field strength at the center. The magnet is H type with 100 mm pole diameter and 60 mm gap size. Comsol, Ansys Maxwell and SolidWorks codes were employed in the design and construction of the electric dipole magnet.

Esophageal atresia (EA) repair can be complicated by associated malformations such as a tracheobronchial remnant in the distal esophagus. We describe our experience with a patient found to have long-gap EA with a distal cartilaginous ring who was managed using a combination of esophageal lengthening and magnetic compression anastomosis. A 5-month-old girl was referred to us from an outside hospital with type C EA including a very high upper pouch. She had undergone a prior thoracotomy with fistula ligation during which a clip was placed on the lower esophagus, leaving a 2-cm diverticulum on the trachea and a short lower esophageal pouch. Upon endoscopic evaluation at our center, we found a tracheobronchial remnant in the lower esophagus between the clip and the carina. An open thoracotomy was performed to approximate the esophageal pouches and a magnet anchor (Connect EA, Myka Laboratories, San Francisco, California, United States) was placed retrograde through the distal esophageal cartilaginous ring into the lower pouch. On postoperative day 8, after adequate growth and decreased pouch tension, a second magnetic anchor was placed endoscopically to the upper pouch to mate with the previously placed lower pouch anchor. The anastomosis formed within 14 days. Due to the tracheobronchial remnant, the device did not pass distally and was removed endoscopically. On postoperative day 8, balloon dilation of the anastomosis and tracheobronchial remnant was performed. Subsequently, the patient required a total of 6 dilations in an 18-month follow-up. This case report illustrates the utility of using magnets to create an esophageal anastomosis in complex cases of EA with concomitant esophageal malformations. The parents of the patient gave their written consent to publish this technical report.

Adverse reactions in tattooed skin during magnetic resonance imaging (MRI) are rare but well known. Previous reports describe sudden burning pain in tattooed skin, sometimes accompanied by mild erythema and oedema when entering MRI scanners. The pathophysiology remains unclear, but simple direct thermal heating can be excluded. It has been hypothesized that MRI-triggered torque and traction create neural sensations from magnetic pigment particles. However, this case enlightens yet another possible mechanism. We present a 35-year-old woman experiencing reoccurring stinging sensations in three decorative black tattoos just seconds after the initiation of the MRI. Single-blind tests with handheld power magnets or a dummy could reproduce painful subjective feelings in her tattooed skin. Similar events were provoked during re-evaluation with MRI. Surprisingly, chemical analyses and electron microscopy of skin samples revealed carbon black as the colouring agent – no iron-based solids were detected. Our case demonstrates that MRI tattoo reactions are not limited to magnetic contaminants alone. More distinct subgroups of MRI-induced reactions may occur. We hypothesize that radiofrequency induction of surface currents in black carbon particles adjacent to sensory axons in the dermis may lead to neurosensations.

L’any 2022, a Manresa s’ha realitzat la primera edició de la Mobile Week amb l’objectiu d’apropar les tecnologies digitals a la ciutat. Des de l’Institut Guillem Catà, a partir del projecte «Magnet-UPC», vam proposar de participar-hi fent la projecció d’un mapping a la façana del centre cultural més gran de la ciutat, el Casino, situat al passeig de Pere III. Així, el dia 6 de maig es va poder dur a la pràctica fruit d’un treball amb l’alumnat de segon d’ESO des de les optatives de robòtica, de visual i plàstica i també de música. Per als nostres alumnes de segon d’ESO l’objectiu era fomentar la creativitat mitjançant tecnologies digitals. Metodològicament, vam seguir el treball conjunt STEAM (science, technology, engineering, arts and mathematics), que implica un treball cooperatiu des de diferents disciplines. El resultat ha estat un exercici rodó que ens ha permès explorar nous terrenys de la creativitat i l’aplicació tecnològica, i que ha repercutit clarament no només en l’entorn immediat de l’Institut sinó a tota la ciutat de Manresa. En conclusió, l’exercici ha esdevingut un veritable estímul a la creació i la recerca entre nois i noies que no en tenien pas experiències prèvies. I és per aquest motiu que ja estem pensant de repetir-lo milloradament el proper curs.

Key Clinical Message Multiple neodymium magnets can pinch tissue and cause barotrauma. Be careful if the tissue of the penis or foreskin is pinched, as this may cause foreskin necrosis or damage to the urethra.

Background and objectivesA totally implantable venous access port (TIVAP) is a commonly used intravenous infusion device for patients receiving chemotherapy or long-term infusion therapy. To improve the success rate of one-time insertion of the Huber needle, we developed a novel Y-Z magnetic TIVAP (Y-Z MTIVAP), which we produced using three-dimensional printing technology.Materials and methodsThe Y-Z MTIVAP includes a magnetic port body and a magnetic positioning device. For testing, we established four venous port implantation models using the two types of TIVAPs and two implantation depth ranges (≤5 mm and >5 mm). Twenty nurses performed Huber needle puncture with the four models, and we recorded the number of attempts required for successful needle insertion, the operation time, and the operator's satisfaction.ResultsThe success rate for one-time needle insertion with the Y-Z MTIVAP was significantly higher than that with the traditional TIVAP at either depth range (100% vs. 75% at ≤5 mm, p = 0.047; 95% vs. 35% at >5 mm, p 5 mm, p = 0.025), but the success rate with the Y-Z MTIVAP was not significantly affected (100% vs. 95%, p = 1.000). The operation time with the Y-Z MTIVAP was significantly shorter than that with the traditional TIVAP at either depth range (both p

In this paper, we present the development of a high-efficiency electronic commutated (EC) motor using nonoriented electrical steel produced by China Steel Corporation for window-type air-conditioning system applications. The EC motor combines the highly efficient brushless DC electric motor, Hall-effect sensor, driver, and AC/DC converter, but it has similar volume and equivalent performance to the traditional AC motor. By analyzing the material properties and using simulation tools, an EC motor with a high efficiency of about 82–86.4% is demonstrated in this study. A system manufacturer can replace the AC motor with an EC motor directly in the air-conditioning system for higher performance and save more energy, without altering the mechanical design. [ABSTRACT FROM AUTHOR]

Pin-based shape-changing displays provide dynamic shape changes by actuating numerous pins. However, the large number of actuators required to move so many pins complicates the electrical path and mechanical structure, and creates a need for significant resources if one is to build such a display. Therefore, my research colleague and I proposed a simple pin-based shape-changing display, called MagneShape, that outputs shapes and motions without any electronic components. MagneShape consists of magnetic pins, a pin housing, and magnetic sheet. The magnetic force generated between the magnetic sheet and the magnetic pins levitates the pins vertically. We devised two methods for fabricating alternative magnetic pins, devised a method for controlling the magnetic pins, and developed design tools for MagneShape. [ABSTRACT FROM AUTHOR]

A prototype of a type A quadrupole magnet has been designed and manufactured for the 3 GeV storage ring of Siam Photon Source II, the second synchrotron light source in Thailand. The required quadrupole gradient is 51 T/m with the magnet effective length being 162 mm. Magnet modeling and magnetic field calculation were performed using Radia and Opera-3D. The bore radius of the magnet is 16 mm. The magnet will be operated at the excitation of 5544 A-turns. A mechanical analysis of the magnet structure was performed in SOLIDWORKS and ANSYS, where the maximum deformation of 0.003 mm was found at the magnet poles, and the first-mode natural frequency was higher than 100 Hz. The magnet yoke is made of AISI 1006 low-carbon steel with a fabrication tolerance of ±0.020 mm. Magnet coils are water-cooled and made of high-purity copper. The temperature rise of the coils was below 3.0 °C at the maximum excitation of 6664 A-turns, which is 20% above the operating point. Magnetic field measurement was carried out using the Hall probe technique. The measured magnetic field and coil temperature of the prototype show good agreement with the calculations. [ABSTRACT FROM AUTHOR]

Adverse reactions in tattooed skin during magnetic resonance imaging (MRI) are rare but well known. Previous reports describe sudden burning pain in tattooed skin, sometimes accompanied by mild erythema and oedema when entering MRI scanners. The pathophysiology remains unclear, but simple direct thermal heating can be excluded. It has been hypothesized that MRI-triggered torque and traction create neural sensations from magnetic pigment particles. However, this case enlightens yet another possible mechanism. We present a 35-year-old woman experiencing reoccurring stinging sensations in three decorative black tattoos just seconds after the initiation of the MRI. Single-blind tests with handheld power magnets or a dummy could reproduce painful subjective feelings in her tattooed skin. Similar events were provoked during re-evaluation with MRI. Surprisingly, chemical analyses and electron microscopy of skin samples revealed carbon black as the colouring agent – no iron-based solids were detected. Our case demonstrates that MRI tattoo reactions are not limited to magnetic contaminants alone. More distinct subgroups of MRI-induced reactions may occur. We hypothesize that radiofrequency induction of surface currents in black carbon particles adjacent to sensory axons in the dermis may lead to neurosensations. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

The ingestion of foreign bodies is a very common emergency in the pediatric age. 80-90% will be expelled without problem, while 10-20% will require endoscopic extraction, and close to 1% will occasionally require surgical intervention. The ingestion of neodymium magnets (rare earth magnets) is increasingly frequent since they are commonly part of toys, accessories or ornaments, they are 5 to 20 times more powerful than conventional iron compound magnets. The vast majority of these accidental ingestions are unnoticed by the parents and the diagnosis is given at the onset of gastrointestinal symptoms such as abdominal pain, nausea, vomiting, although on occasions they may be asymptomatic and/or as a radiological finding. We present the clinical case of a 2-year-old male, with a history of autism, who was admitted due to abdominal pain, in whom foreign body ingestion (magnets) was noted when performing an abdominal X-ray, in different locations, requiring exploratory laparotomy, finding internal hernia secondary to enteroenteric fistula as a finding, as well as multiple entero-enteral fistulas. [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. [ABSTRACT FROM AUTHOR]

High-density on-board optical connectors are necessary for next-generation optical interconnects such as co-packaged optics in datacenter networks. To break through the size limitation of current optical connectors, we proposed the concept of introducing a magnetic attraction structure into an optical-fiber connector. We previously developed simplex and multi-fiber connectors on the basis of this concept. This article reviews the design and fabrication results of our developed multi-fiber magnetic connector, which provided low-insertion losses comparable to those of conventional multi-fiber push-on connectors while achieving space-saving connection. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Accidental ingestion of magnetic foreign bodies has become more common due to the greater availability of toys with these elements, being a clinical problem between 6 months and 3 years of age, which must be treated promptly since they could cause life-threatening gastrointestinal complications. CLINICAL CASE: A 4-year-old male schoolboy, who presented abdominal pain of 4 days of evolution, colic type, intermittent, without other symptoms; clinically stable, the abdomen without data of peritoneal irritation. An AP and lateral standing X-ray of the abdomen is performed, which shows images of radiopaque foreign bodies (chain of magnets) in the gastric chamber and partial intestinal pneumatization. An endoscopy was performed where 4 spherical magnets embedded in the gastric mucosa that conditioned transmural perforation were visualized. An exploratory laparotomy was performed, finding a perforation in the posterior face of the gastric body that fistulized towards the jejunum and another mirror perforation in the colon, and a chain of 15 circumferential magnets was extracted from the gastric cavity. CONCLUSION: The ingestion of magnets must be diagnosed in a timely manner through a directed questioning, based on a simple abdominal X-ray, since this will define the diagnosis and early endoscopic and/or surgical treatment and thus avoid greater gastrointestinal complications secondary to the electromagnetic charge of the magnets, time of ingestion, location and number of foreign bodies. [ABSTRACT FROM AUTHOR]

In this manuscript we deal with recent advances in low-field Magnetic Resonance Imaging (MRI). The development of low-cost MRI solutions allowing portability and trustable diagnosis is a hot topic worldwide by these days. We analyze basic technical issues of recent examples of fixed-field instruments operating at low-field. Then we discuss pros and cons of the pre-polarized approach, from both physical and technical perspectives. Permanent magnet and electromagnet technology are confronted. Finally, magnetic field-cycling is introduced as an alternative MRI technique, where field-dependent experiments can be exploded for the development of new contrast mechanisms that are not feasible for fixed-field MRI instruments. As field cycled machines usually deals with switched currents in electromagnets, magnetic field instability and inhomogeneity are the main limiting factors affecting image quality. We finalize this manuscript discussing how it turns possible to overcome these limitations, thus opening new possibilities for the development of cost effective MRI technology.

In 2023, the manufacturing of all the ITER TF coils has been completed 15 years after the sign of procurement arrangements in 2008. This paper has been jointly submitted by F4E and QST to recollect the lessons learnt in the production of the two parties along the last 15 years.

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.