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1.
PLoS One ; 19(6): e0302983, 2024.
Article de Anglais | MEDLINE | ID: mdl-38900781

RÉSUMÉ

Rice wine, known as yellow wine in China and Japan, possesses considerable nutritional value and holds significant global influence. This study addresses the challenge of preserving rice wine, which is prone to rancidity due to its low alcohol content. Conventional storage techniques employing pottery jars often result in substantial spoilage losses. Through rigorous investigation, this research identifies a polarization phenomenon exhibited by degraded rice wine when subjected to high-frequency microwaves(>60GHz), presenting a pioneering method for detecting spoilage, even within sealed containers. Employing a multi-channel microwave radar apparatus, the study delves into the susceptibility of rice wine to electromagnetic waves across various frequencies, uncovering pronounced polarization traits in deteriorated samples within the E-band microwave spectrum. Furthermore, lab-controlled simulations elucidate a direct correlation between physicochemical alterations and high-frequency Radar Cross Section (RCS) signals during the wine's deterioration process. A novel six-membered Hydrated Cluster hypothesis is proposed, offering insights into the molecular mechanisms underlying this phenomenon. Additionally, dielectric property assessments conducted using vector network analyzers (VNA) reveal noteworthy enhancements in the dielectric constant of deteriorated rice wine, particularly within the high-frequency domain, thereby augmenting detectability. These findings carry implications for refining rice wine preservation techniques and contribute to the advancement of non-destructive testing technologies, enabling the detection of rice wine deterioration or indications thereof, even within sealed vessels.


Sujet(s)
Oryza , Vin , Vin/analyse , Oryza/composition chimique , Micro-ondes , Japon , Phénomènes électromagnétiques , Chine
2.
Sci Rep ; 14(1): 14161, 2024 06 19.
Article de Anglais | MEDLINE | ID: mdl-38898086

RÉSUMÉ

Ultrasound (US) has gained popularity as a guidance modality for percutaneous needle insertions because it is widely available and non-ionizing. However, coordinating scanning and needle insertion still requires significant experience. Current assistance solutions utilize optical or electromagnetic tracking (EMT) technology directly integrated into the US device or probe. This results in specialized devices or introduces additional hardware, limiting the ergonomics of both the scanning and insertion process. We developed the first ultrasound (US) navigation solution designed to be used as a non-permanent accessory for existing US devices while maintaining the ergonomics during the scanning process. A miniaturized EMT source is reversibly attached to the US probe, temporarily creating a combined modality that provides real-time anatomical imaging and instrument tracking at the same time. Studies performed with 11 clinical operators show that the proposed navigation solution can guide needle insertions with a targeting accuracy of about 5 mm, which is comparable to existing approaches and unaffected by repeated attachment and detachment of the miniaturized tracking solution. The assistance proved particularly helpful for non-expert users and needle insertions performed outside of the US plane. The small size and reversible attachability of the proposed navigation solution promises streamlined integration into the clinical workflow and widespread access to US navigated punctures.


Sujet(s)
Phénomènes électromagnétiques , Aiguilles , Humains , Échographie interventionnelle/méthodes , Échographie interventionnelle/instrumentation , Miniaturisation , Conception d'appareillage , Fantômes en imagerie
3.
PLoS One ; 19(6): e0304052, 2024.
Article de Anglais | MEDLINE | ID: mdl-38913628

RÉSUMÉ

A diaphragm pump is a type of volumetric pump that has excellent sealing performance. An electromagnetic diaphragm pump is a kind of widely adopted diaphragm pump that has a simple structure, low power loss, and high cost performance. However, the calculation method of deformation for the electromagnetic diaphragm pump rubber diaphragm is presently lacking. Herein, a calculating method of deformation for the electromagnetic diaphragm pump rubber diaphragm is proposed. By establishing and analyzing a deformation model of the electromagnetic diaphragm pump rubber diaphragm, a theoretical relationship between the deformation of the electromagnetic diaphragm pump rubber diaphragm, the size of the electromagnetic diaphragm pump rubber diaphragm and the pressure of fluid is determined. The experimental results indicate that the biggest difference between the tested axial deformation and the calculated axial deformation of the electromagnetic diaphragm pump rubber diaphragm is 0.04 mm and the calculation results show agreement with the experimental results.


Sujet(s)
Phénomènes électromagnétiques , Caoutchouc , Caoutchouc/composition chimique , Conception d'appareillage , Modèles théoriques
4.
Int J Pharm ; 658: 124185, 2024 Jun 10.
Article de Anglais | MEDLINE | ID: mdl-38703932

RÉSUMÉ

Production of amorphous solid dispersions (ASDs) is an effective strategy to promote the solubility and bioavailability of poorly water soluble medicinal substances. In general, ASD is manufactured using a variety of classic and modern techniques, most of which rely on either melting or solvent evaporation. This proof-of-concept study is the first ever to introduce electromagnetic drop-on-demand (DoD) technique as an alternative solvent evaporation-based method for producing ASDs. Herein 3D printing of ASDs for three drug-polymer combinations (efavirenz-Eudragit L100-55, lumefantrine-hydroxypropyl methylcellulose acetate succinate, and favipiravir-polyacrylic acid) was investigated to ascertain the reliability of this technique. Polarized light microscopy, differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and Fourier Transform  Infrared (FTIR) spectroscopy results supported the formation of ASDs for the three drugs by means of DoD 3D printing, which significantly increases the equilibrium solubility of efavirenz from 0.03 ± 0.04 µg/ml to 21.18 ± 4.20 µg/ml, and the equilibrium solubility of lumefantrine from 1.26 ± 1.60 µg/ml to 20.21 ± 6.91 µg/ml. Overall, the reported findings show how this new electromagnetic DoD technology can have a potential to become a cutting-edge 3D printing solvent-evaporation technique for on-demand and continuous manufacturing of ASDs for a variety of drugs.


Sujet(s)
Impression tridimensionnelle , Solubilité , Technologie pharmaceutique/méthodes , Préparation de médicament/méthodes , Polymères/composition chimique , Phénomènes électromagnétiques , Étude de validation de principe , Diffraction des rayons X , Chimie pharmaceutique/méthodes
5.
Ther Adv Respir Dis ; 18: 17534666241249150, 2024.
Article de Anglais | MEDLINE | ID: mdl-38757612

RÉSUMÉ

BACKGROUND: Although electromagnetic navigation bronchoscopy (ENB) is highly sensitive in the diagnosis of peripheral pulmonary nodules (PPNs), its diagnostic yield for subgroups of smaller PPNs is under evaluation. OBJECTIVES: Diagnostic yield evaluation of biopsy using ENB for PPNs <2 cm. DESIGN: The diagnostic yield, sensitivity, specificity, positive predictive value, and negative predictive value of the ENB-mediated biopsy for PPNs were evaluated. METHODS: Patients who had PPNs with diameters <2 cm and underwent ENB-mediated biopsy between May 2015 and February 2020 were consecutively enrolled. The final diagnosis was made via pathological examination after surgery. RESULTS: A total of 82 lesions from 65 patients were analyzed. The median tumor size was 11 mm. All lesions were subjected to ENB-mediated biopsy, of which 29 and 53 were classified as malignant and benign, respectively. Subsequent segmentectomy, lobectomy, or wedge resection, following pathological examinations were performed on 64 nodules from 57 patients. The overall sensitivity, specificity, positive predictive value, and negative predictive value for nodules <2 cm were 53.3%, 91.7%, 92.3%, and 51.2%, respectively. The receiver operating curve showed an area under the curve of 0.721 (p < 0.001). Additionally, the sensitivity, specificity, positive predictive value, and negative predictive value were 62.5%, 100%, 100%, and 42.9%, respectively, for nodules with diameters equal to or larger than 1 cm; and 30.8%, 86.7%, 66.7%, and 59.1%, respectively, for nodules less than 1 cm. In the subgroup analysis, neither the lobar location nor the distance of the PPNs to the pleura affected the accuracy of the ENB diagnosis. However, the spiculated sign had a negative impact on the accuracy of the ENB biopsy (p = 0.010). CONCLUSION: ENB has good specificity and positive predictive value for diagnosing PPNs <2 cm; however, the spiculated sign may negatively affect ENB diagnostic accuracy. In addition, the diagnostic reliability may only be limited to PPNs equal to or larger than 1 cm.


Sujet(s)
Bronchoscopie , Phénomènes électromagnétiques , Tumeurs du poumon , Nodules pulmonaires multiples , Valeur prédictive des tests , Humains , Bronchoscopie/méthodes , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/diagnostic , Nodules pulmonaires multiples/anatomopathologie , Nodules pulmonaires multiples/diagnostic , Nodules pulmonaires multiples/chirurgie , Études rétrospectives , Charge tumorale , Adulte , Nodule pulmonaire solitaire/anatomopathologie , Nodule pulmonaire solitaire/diagnostic , Nodule pulmonaire solitaire/chirurgie , Nodule pulmonaire solitaire/imagerie diagnostique , Reproductibilité des résultats , Sujet âgé de 80 ans ou plus , Biopsie guidée par l'image/méthodes
6.
J Orthop Surg Res ; 19(1): 304, 2024 May 20.
Article de Anglais | MEDLINE | ID: mdl-38769535

RÉSUMÉ

BACKGROUND: Periprosthetic joint infection is a serious complication following joint replacement. The development of bacterial biofilms bestows antibiotic resistance and restricts treatment via implant retention surgery. Electromagnetic induction heating is a novel technique for antibacterial treatment of metallic surfaces that has demonstrated in-vitro efficacy. Previous studies have always employed stationary, non-portable devices. This study aims to assess the in-vitro efficacy of induction-heating disinfection of metallic surfaces using a new Portable Disinfection System based on Induction Heating. METHODS: Mature biofilms of three bacterial species: S. epidermidis ATCC 35,984, S. aureus ATCC 25,923, E. coli ATCC 25,922, were grown on 18 × 2 mm cylindrical coupons of Titanium-Aluminium-Vanadium (Ti6Al4V) or Cobalt-chromium-molybdenum (CoCrMo) alloys. Study intervention was induction-heating of the coupon surface up to 70ºC for 210s, performed using the Portable Disinfection System (PDSIH). Temperature was monitored using thermographic imaging. For each bacterial strain and each metallic alloy, experiments and controls were conducted in triplicate. Bacterial load was quantified through scraping and drop plate techniques. Data were evaluated using non-parametric Mann-Whitney U test for 2 group comparison. Statistical significance was fixed at p ≤ 0.05. RESULTS: All bacterial strains showed a statistically significant reduction of CFU per surface area in both materials. Bacterial load reduction amounted to 0.507 and 0.602 Log10 CFU/mL for S. aureus on Ti6Al4V and CoCrMo respectively, 5.937 and 3.500 Log10 CFU/mL for E. coli, and 1.222 and 0.372 Log10 CFU/mL for S. epidermidis. CONCLUSIONS: Electromagnetic induction heating using PDSIH is efficacious to reduce mature biofilms of S aureus, E coli and S epidermidis growing on metallic surfaces of Ti6Al4V and CoCrMo alloys.


Sujet(s)
Alliages , Biofilms , Désinfection , Escherichia coli , Infections dues aux prothèses , Staphylococcus aureus , Titane , Biofilms/effets des médicaments et des substances chimiques , Désinfection/méthodes , Escherichia coli/croissance et développement , Staphylococcus aureus/effets des médicaments et des substances chimiques , Infections dues aux prothèses/prévention et contrôle , Infections dues aux prothèses/microbiologie , Staphylococcus epidermidis/effets des médicaments et des substances chimiques , Prothèse articulaire/microbiologie , Arthroplastie prothétique/instrumentation , Arthroplastie prothétique/méthodes , Chauffage/instrumentation , Chauffage/méthodes , Humains , Phénomènes électromagnétiques , Vitallium
7.
Bioresour Technol ; 402: 130844, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38754560

RÉSUMÉ

In this study, a novel magnetic Ni-Fe2O3-C catalyst combined with electromagnetic induction heating in biomass steam gasification was proposed to enhance H2 production. Better catalytic performance for H2 production was observed with the Ni-Fe2O3-C catalyst under induction heating, resulting in an increase in H2 yield from 735.1 to 2271.2 mL/g-biomass (a 209.1 % enhancement). SEM, TGA and XRD analysis demonstrated a significant decrease in coking deposition, caking, and particle agglomeration of the Ni-Fe2O3-C catalyst under induction heating, while maintaining more active sites. Importantly, the benefits of induction heating were also applicable to different magnetic catalysts like Ni-Al2O3-C, Ni-ZrO2-C, and Ni-MgO-C. Experimental results revealed a logarithmic correlation between the increase in H2 yields due to induction heating and the magnetic saturation (Ms) of the catalysts. The Ni-Fe2O3-C catalyst, with a high Ms of 50.9 emu/g, showed the highest catalytic activity for H2 production under induction heating in this study.


Sujet(s)
Biomasse , Composés du fer III , Hydrogène , Nickel , Vapeur , Catalyse , Hydrogène/composition chimique , Nickel/composition chimique , Composés du fer III/composition chimique , Température élevée , Chauffage , Diffraction des rayons X , Phénomènes électromagnétiques
8.
Sci Rep ; 14(1): 10055, 2024 05 02.
Article de Anglais | MEDLINE | ID: mdl-38698058

RÉSUMÉ

Endoscopic transgastric necrosectomy is crucial in the management of complications resulting from necrotizing pancreatitis. However, both real-time and visual-spatial information is lacking during the procedure, thereby jeopardizing a precise positioning of the endoscope. We conducted a proof-of-concept study with the aim of overcoming these technical difficulties. For this purpose, a three-dimensional (3D) phantom of a stomach and pancreatic necroses was 3D-printed based on spatial information from individual patient CT scans and subsequently integrated into a silicone torso. An electromagnetic (EM) sensor was adjusted inside the endoscope´s working channel. A software interface enabled real time visualization. The accuracy of this novel assistant system was tested ex vivo by four experienced interventional endoscopists who were supposed to reach seven targets inside the phantom in six different experimental runs of simulated endoscopic transgastric necrosectomy. Supported by endoscopic camera view combined with real-time 3D visualization, all endoscopists reached the targets with a targeting error ranging between 2.6 and 6.5 mm in a maximum of eight minutes. In summary, the EM tracking system might increase efficacy and safety of endoscopic transgastric necrosectomy at the experimental level by enhancing visualization. Yet, a broader feasibility study and further technical improvements are mandatory before aiming at implementation into clinical setting.


Sujet(s)
Phénomènes électromagnétiques , Humains , Fantômes en imagerie , Estomac/chirurgie , Estomac/imagerie diagnostique , Pancréatite aigüe nécrotique/chirurgie , Pancréatite aigüe nécrotique/imagerie diagnostique , Endoscopie/méthodes , Pancréas/chirurgie , Impression tridimensionnelle , Systèmes de navigation chirurgicale , Imagerie tridimensionnelle/méthodes
9.
Sensors (Basel) ; 24(10)2024 May 11.
Article de Anglais | MEDLINE | ID: mdl-38793913

RÉSUMÉ

The purpose of this paper is to demonstrate a new discovery regarding the interaction between materials and very low radio frequencies. Specifically, we observed a feedback response on an inertia active sensor when specific frequencies (around 2-4 kHz) are used to irradiate targeted pharmaceutical samples like aspirin or paracetamol drugs. The characteristics of this phenomenon, such as excitation and relaxation time, the relation between deceleration and a material's quantity, and signal amplitude, are presented and analyzed. Although the underlying physics of this phenomenon is not yet known, we have shown that it has potential applications in remote identification of compounds, detection, and location sensing, as well as identifying substances that exist in plants without the need for any processing. This method is fast, accurate, low-cost, non-destructive, and non-invasive, making it a valuable area for further research that could yield spectacular results in the future.


Sujet(s)
Acétaminophène , Acétaminophène/analyse , Acétaminophène/composition chimique , Phénomènes électromagnétiques , Acide acétylsalicylique/composition chimique , Acide acétylsalicylique/analyse , Préparations pharmaceutiques/composition chimique , Préparations pharmaceutiques/analyse , Ondes hertziennes
10.
World Neurosurg ; 187: 19-28, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38583569

RÉSUMÉ

BACKGROUND: Ventriculoscopic neuronavigation has been described in several articles. However, there are different ventriculoscopes and navigation systems. Due to these different combinations, it is difficult to find detailed neuronavigation protocols. We describe, step-by-step, a simple method to navigate both the trajectory until reaching the ventricular system, as well as the intraventricular work. METHODS: We use a rigid ventriculoscope (LOTTA, KarlStorz) with an electromagnetic stylet (S8-StealthSystem, Medtronic). The protocol is based on a modified or 3-dimensionally printed trocar for navigating the extraventricular step and on a modified pediatric nasogastric tube for the intraventricular navigation. RESULTS: This protocol can be set up in less than 10 minutes. The extraventricular part is navigated by introducing the electromagnetic stylet inside the modified or 3-dimensionally printed trocar. Intraventricular navigation is done by combining a modified pediatric nasogastric tube with the electromagnetic stylet inside the endoscope's working channel. The most critical point is to obtain a blunt-bloodless ventriculostomy while achieving perfect alignment of all targeted structures via pure straight trajectories. CONCLUSIONS: This protocol is easy-to-set-up, avoids head rigid-fixation and bulky optical-based attachments to the ventriculoscope, and allows continuous navigation of both parts of the surgery. Since we have implemented this protocol, we have noticed a significant enhancement in both simple and complex ventriculoscopic procedures because the surgery is dramatically simplified.


Sujet(s)
Neuroendoscopes , Neuroendoscopie , Neuronavigation , Ventriculostomie , Flux de travaux , Humains , Neuronavigation/méthodes , Neuronavigation/instrumentation , Neuroendoscopie/méthodes , Neuroendoscopie/instrumentation , Ventriculostomie/méthodes , Ventriculostomie/instrumentation , Phénomènes électromagnétiques , Impression tridimensionnelle
11.
BMJ Open Ophthalmol ; 9(1)2024 Apr 04.
Article de Anglais | MEDLINE | ID: mdl-38575345

RÉSUMÉ

OBJECTIVE: Preclinical validation study to assess the feasibility and accuracy of electromagnetic image-guided systems (EM-IGS) in orbital surgery using high-fidelity physical orbital anatomy simulators. METHODS: EM-IGS platform, clinical software, navigation instruments and reference system (StealthStation S8, Medtronic) were evaluated in a mock operating theatre at the Royal Victoria Eye and Ear Hospital, a tertiary academic hospital in Dublin, Ireland. Five high-resolution 3D-printed model skulls were created using CT scans of five anonymised patients with an orbital tumour that previously had a successful orbital biopsy or excision. The ability of ophthalmic surgeons to achieve satisfactory system registration in each model was assessed. Subsequently, navigational accuracy was recorded using defined anatomical landmarks as ground truth. Qualitative feedback on the system was also attained. RESULTS: Three independent surgeons participated in the study, one junior trainee, one fellow and one consultant. Across models, more senior participants were able to achieve a smaller system-generated registration error in a fewer number of attempts. When assessing navigational accuracy, submillimetre accuracy was achieved for the majority of points (16 landmarks per model, per participant). Qualitative surgeon feedback suggested acceptability of the technology, although interference from mobile phones near the operative field was noted. CONCLUSION: This study suggests the feasibility and accuracy of EM-IGS in a preclinical validation study for orbital surgery using patient specific 3D-printed skulls. This preclinical study provides the foundation for clinical studies to explore the safety and effectiveness of this technology.


Sujet(s)
Chirurgie assistée par ordinateur , Humains , Orbite/imagerie diagnostique , Tomodensitométrie , Logiciel , Phénomènes électromagnétiques
12.
Otolaryngol Pol ; 78(2): 50-54, 2024 Apr 09.
Article de Anglais | MEDLINE | ID: mdl-38623855

RÉSUMÉ

<b><br>Aim:</b> The aim of the study was to evaluate the results of electrical safety results of a prototype electromagnetic ear stimulation device in patients with tinnitus.</br> <b><br>Material and methods:</b> The electrical safety tests of the prototype device for electro- and magnetostimulation of the hearing organ were carried out at the Center for Attestation and Certification Tests in Gliwice. The tests concerned selected parameters including the PN-EN standard.</br> <b><br>Results:</b> Safety studies of the prototype electrical stimulation device for the ear in patients with tinnitus were necessary to perform the planned further preclinical studies. Obtained results regarding: identification and labeling of the device; protection against electric shock; checking protective earthing, functional earthing and potential equalization; checking the leakage current and auxiliary currents of the patient; checking the distances through the solid insulation and the use of thin insulating spacers; checking the electrical strength of the device insulation; checking protection against mechanical hazards of the device; checking the risk associated with surfaces, corners and edges, and checking the protection against excessive temperatures and other threats comply with the standard PN-EN.</br> <b><br>Conclusions:</b> No risk to the patient and medical staff. Tests of protection against mechanical hazards of the device have shown that the only movable part whose contact with the patient could cause an unacceptable risk is the fan installed inside the housing.</br>.


Sujet(s)
Acouphène , Humains , Acouphène/thérapie , Phénomènes électromagnétiques
14.
J Robot Surg ; 18(1): 149, 2024 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-38564059

RÉSUMÉ

Pulmonary nodules are frequently encountered in high-risk patients. Often these require biopsy which can be challenging. We relate our experience comparing use of electromagnetic navigational bronchoscopy (ENB) to a robotic bronchoscopy system (RB). A retrospective review of patients undergoing bronchoscopic biopsy from 2015 to 2021. The timeframe overlapped with transition from ENB using Veran SPiN system to RB using Ion system by Intuitive. Patient and nodule characteristics were collected. Primary end point was overall diagnostic yield which was defined by pathologic confirmation of malignancy or benign finding. Secondary outcomes included diagnostic yield based on overall size of nodules and need for further work up and testing. 116 patients underwent ENB or RB of 134 nodules. No perioperative complications occurred. Diagnostic yield of ENB was 49.5% (41/91 nodules) versus 86.1% (37/43 nodules) for RB. Average nodule size for ENB was 2.55 cm versus 1.96 cm for RB. When divided based on size, ENB had a 30% diagnostic yield for nodules 1-2 cm (11/37 nodules, mean size 1.46 cm) and 64% yield for nodules 2-3 cm (14/22 nodules, mean size 2.38 cm). RB had an 81% yield for nodules 1-2 cm (mean size 1.41 cm) and 100% yield for nodules 2-3 cm (mean 2.3 cm). RB showed superiority over ENB in early implementation trials for biopsy of suspicious pulmonary nodules. It is a safe technology allowing for increased access to all lung fields and utilization in the thoracic surgical practice will be paramount to advancing the field.


Sujet(s)
Interventions chirurgicales robotisées , Chirurgie thoracique , Humains , Bronchoscopie , Interventions chirurgicales robotisées/méthodes , Biopsie , Phénomènes électromagnétiques
15.
Int J Biol Macromol ; 265(Pt 2): 130957, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38499121

RÉSUMÉ

Deterioration in mechanical performances and aging resistance due to the introduction of flame retardants is a major obstacle for bio-based fire-safety polypropylene (PP). Herein, we reported a kind of functionalized lignin nanoparticles assembled with MXene (MX@LNP), and applied it to construct the flame-retardant PP composites (PP-MA) with superior fire safety, excellent mechanical performance, electromagnetic shielding effects and aging resistance. Specifically, the PP-MA doped with only 18 wt% flame-retardant additives (PP-MA18) achieved the UL-94 V-0 rating. In comparison to pure PP, PP-MA18 presented a greatly decreased peak of heat release rate (pHRR), total heat rate (THR), and peak smoke production rate (pSPR) by 79.7 %, 69.0 % and 75.8 %, respectively, and satisfactory decrease in total flammable and toxic volatiles evolved. The formed fine solid microstructure of carbon residuals effectively promoted the compactness of char layers. More importantly, the nano-effect and the strong interface interaction between the complexed MX@LNP and PP enhanced the tensile strength (45.78 MPa) and elongation at break (725.95 %) of PP-MA. Additionally, the significant ultraviolet absorption and electromagnetic wave dissipation performance of MXene and lignin enabled excellent aging resistance and electromagnetic shielding effects of PP-MA compared with PP. This achieved MX@LNP afforded a novel approach for developing flame retardant materials with excellent application performance.


Sujet(s)
Ignifuges , Nanoparticules , Nitrites , Éléments de transition , Lignine , Polypropylènes , Phénomènes électromagnétiques
16.
Hum Brain Mapp ; 45(5): e26638, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38520365

RÉSUMÉ

Connectome spectrum electromagnetic tomography (CSET) combines diffusion MRI-derived structural connectivity data with well-established graph signal processing tools to solve the M/EEG inverse problem. Using simulated EEG signals from fMRI responses, and two EEG datasets on visual-evoked potentials, we provide evidence supporting that (i) CSET captures realistic neurophysiological patterns with better accuracy than state-of-the-art methods, (ii) CSET can reconstruct brain responses more accurately and with more robustness to intrinsic noise in the EEG signal. These results demonstrate that CSET offers high spatio-temporal accuracy, enabling neuroscientists to extend their research beyond the current limitations of low sampling frequency in functional MRI and the poor spatial resolution of M/EEG.


Sujet(s)
Connectome , Humains , Connectome/méthodes , Électroencéphalographie/méthodes , Encéphale/imagerie diagnostique , Encéphale/physiologie , Imagerie par résonance magnétique/méthodes , Phénomènes électromagnétiques
17.
World J Urol ; 42(1): 124, 2024 Mar 07.
Article de Anglais | MEDLINE | ID: mdl-38453751

RÉSUMÉ

BACKGROUND: Extracorporeal shock wave lithotripsy represents one option for the non-surgical management of Peyronie's disease. Despite promising results, several questions are still pending. We want to present the long-term results of a retrospective study using high-energy extracorporeal shock wave lithotripsy. MATERIAL AND METHODS: We evaluated retrospectively 110 patients treated between 1996 and 2020 at the Department of Urology, SLK Kliniken Heilbronn for chronic phase Peyronie's disease using two electromagnetic lithotripters (Siemens Lithostar Plus Overhead Module, Siemens Lithoskop) applying high-energy shock waves under local anesthesia and sonographic or fluoroscopic control. A standardized questionnaire focused on the change in pain, curvature, sexual function and the need of penile surgery. RESULTS: In 85 of the 110 patients (mean age 54 years) we had sufficient data for evaluation. The median follow-up was 228 (6-288) months. There were no significant complications. Pain reduction was achieved in all patients, 65 (76%) patients were free of pain. Improvement of penile curvature was achieved in 43 patients (51%) ranging from 25% improvement (deflected angle < 30°) to 95% (angle 30-60°). 59 patients (69%) reported problems with sexual intercourse, 40 of those (68%) reported improvement. Only 9 (10.5%) patients underwent surgical correction. We did not observe any significant differences between both electromagnetic devices with stable long-term results. CONCLUSIONS: High-energy shock wave therapy delivered by two standard electromagnetic lithotripters is safe and efficient providing stable long-term results. In cases with significant plaque formation, the concept of high-energy ESWT should be considered in future studies.


Sujet(s)
Ondes de choc de haute énergie , Lithotritie , Induration plastique des corps caverneux du pénis , Mâle , Humains , Adulte d'âge moyen , Induration plastique des corps caverneux du pénis/thérapie , Études rétrospectives , Pénis , Douleur , Phénomènes électromagnétiques , Résultat thérapeutique
18.
ACS Appl Mater Interfaces ; 16(11): 13597-13610, 2024 Mar 20.
Article de Anglais | MEDLINE | ID: mdl-38453642

RÉSUMÉ

Atmospheric pressure coaxial gaseous discharge tubes (DTs) with helium have demonstrated potential for in vitro inactivation or sensitization of glioblastoma cancer cells. Here, we study the effect of two configurations of the DT electrode system on its electromagnetic emissivity as well as other physical factors (heating and UV emission) that form in the vicinity of this device. We demonstrate that the configuration of the DT electrodes that concentrates the discharge streamers near the top of the device has a distant (cm scale) deactivation effect on U87-MG glioblastoma cancer cells when irradiated, without measurable UV components in the DT optical emission spectra. This effect persists even through different barriers such as glass, plastic, or quartz Petri dishes but is eliminated when glass or plastic dishes are filled with water. These findings demonstrate the potential for development of noninvasive, physical-based treatment methods of deep-tissue tumors.


Sujet(s)
Glioblastome , Gaz plasmas , Humains , Gaz plasmas/pharmacologie , Hélium , Glioblastome/thérapie , Phénomènes électromagnétiques , Pression atmosphérique
20.
Med Phys ; 51(5): 3184-3194, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38456608

RÉSUMÉ

BACKGROUND: Electromagnetic tracking (EMT) systems have proven to be a valuable source of information regarding the location and geometry of applicators in patients undergoing brachytherapy (BT). As an important element of an enhanced and individualized pre-treatment verification, EMT can play a pivotal role in detecting treatment errors and uncertainties to increase patient safety. PURPOSE: The purpose of this study is two-fold: to design, develop and test a dedicated measurement protocol for the use of EMT-enabled afterloaders in BT and to collect and compare the data acquired from three different radiation oncology centers in different clinical environments. METHODS: A novel quality assurance (QA) phantom composed of a scaffold with supports to fix the field generator, different BT applicators, and reference sensors (sensor verification tools) was used to assess the precision (jitter error) and accuracy (relative distance errors and target registration error) of the EMT sensor integrated into an afterloader prototype. Measurements were repeated in different environments where EMT measurements are likely to be performed, namely an electromagnetically clean laboratory, a BT suite, an operating room, and, if available, a CT suite and an MRI suite dedicated to BT. RESULTS: The mean positional jitter was consistently under 0.1 mm across all measurement points, with a slight trend of increased jitter at greater distances from the field generator. The mean variability of sensor positioning in the tested tandem and ring gynecological applicator was also below 0.1 mm. The tracking accuracy close to the center of the measurement volume was higher than at its edges. The relative distance error at the center was 0.2-0.3 mm with maximum values reaching 1.2-1.8 mm, but up to 5.5 mm for measurement points close to the edges. In general, similar accuracy results were obtained in the clinical environments and in all investigated institutions (median distance error 0.1-0.4 mm, maximum error 1.0-2.0 mm), however, errors were found to be larger in the CT suite (median distance error up to 1.0 mm, maximum error up to 3.6 mm). CONCLUSION: The presented quality assessment protocol for EMT systems in BT has demonstrated that EMT offers a high-accuracy determination of the applicator/implant geometry even in clinical environments. In addition to that, it has provided valuable insights into the performance of EMT-enabled afterloaders across different radiation oncology centers.


Sujet(s)
Curiethérapie , Phénomènes électromagnétiques , Assurance de la qualité des soins de santé , Curiethérapie/instrumentation , Humains , Fantômes en imagerie , Contrôle de qualité
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