Magnetic Seeds Research Articles

Roles of magnetic coagulation in black-odor water restoration: An insight into dissolved organic matters

The black-odor water body restoration is an unfinished business in protecting and maintaining the ecological functions of natural water systems in China. Magnetic coagulation (MC) had found a vast application prospect for its high-efficient separation. In this work, the performance of MC was analyzed to explore its role in natural water protection, with a focus on identification and removal mechanisms of the dissolved organic matters (DOM) by absorption and fluorescence spectroscopy in terms of the spectroscopic indices, two-dimensional correlation spectroscopy (2D-COS), and parallel factor analysis (PARAFAC) methods. MC presented an excellent performance for suspended and colloidal matters, phosphorus, and DOMs, and showed high adaptability in pollution interception and water restoration. Tryptophan-like, tyrosine-like, and humics were identified as the key components in the wastewater, which were mainly recently produced or microbial-derived. The targeted pollutants were DOMs with high molecular weight, hydrophobicity, polarity, and aromaticity for the high affinity with the hydrolyzed Al species. Polyaluminum chloride (PAC) was the key in dissolved pollutants removal, while the mix stage is crucial for DOMs with low MW or humic-like substances as PAM facilitated the flocs formation and the absorption process. However, the residual PAM and the redissolved DOMs from the recycled magnetic seeds also act as the DOM source. This work identified the DOM composition and removal mechanism in MC, which would promote its application in natural water protection.

Efficacy and Accuracy of Using Magnetic Seed for Preoperative Non-Palpable Breast Lesions Localization: Our Experience with Magseed.

In this retrospective study we share our single-center experience using a magnetic seed for the preoperative localization of non-palpable breast lesions. Patients who underwent a preoperative localization with Magseed® (Endomagnetics, Cambridge, UK) placement between 2020 and 2022 were enrolled. Indications to Magseed placement have been established during multidisciplinary meetings prior to surgery and all patients underwent breast-conserving surgery (BCS). 45 patients were included. Magnetic seeds have been introduced under ultrasound guidance in 40 patients (88.9%) and under stereotactic guidance in 5 patients (11.1%). We registered a highly successful placement rate (97.8%), with only one case of migration (2.2%). After BCS, all the magnetic seeds were recovered (100% retrieval rate). The re-excision rate for positive margins was 0%. Our experience, with a highly successful placement and retrieval rate and a re-excision rate equal to 0%, is consistent with the encouraging literature published on Magseed so far, suggesting this technique to be extremely effective. Moreover, our single case of seed migration supports the existing data stating that Magseed migration is rare. In conclusion, despite acknowledging Magseed limitations, we highly value the advantages linked to this technique, and we, therefore, uphold its use.

Image-guided Localisation of Nonpalpable Breast Lesions: a Comparative Analysis of Magnetic Seeds and Hookwires in an Asian Population

Image-guided Localisation of Nonpalpable Breast Lesions: a Comparative Analysis of Magnetic Seeds and Hookwires in an Asian Population

Axillary Staging after Neoadjuvant Chemotherapy for Initially Node-Positive Breast Carcinoma in Germany: Initial Data from the AXSANA study.

Introduction To date, the optimal axillary staging procedure for initially node-positive breast carcinoma patients after neoadjuvant chemotherapy (NACT) has been unclear. The aim of the AXSANA study is to prospectively compare different surgical staging techniques with respect to the oncological outcome and quality of life for the patients. Little is known about current clinical practice in Germany. Material and Methods In this paper we analyzed data from patients enrolled in the AXSANA study at German study sites from June 2020 to March 2022. Results During the period under investigation, 1135 patients were recruited at 143 study sites. More than three suspicious lymph nodes were initially found in 22% of patients. The target lymph node (TLN) was marked in 64% of cases. This was done with clips/coils in 83% of patients, with magnetic seeds or carbon suspension in 8% each, and with a radar marker in 1% of patients. After NACT, targeted axillary dissection (TAD) or axillary lymphadenectomy (ALND) were each planned in 48% of patients, and sentinel lymph node biopsy alone (SLNB) in 2%. Clinically, the nodal status after NACT was found to be unremarkable in 65% of cases. Histological lymph node status was correctly assessed by palpation in 65% of patients and by sonography in 69% of patients. Conclusion At the German AXSANA study sites, TAD and ALND are currently used as the most common surgical staging procedures after NACT in initially node-positive breast cancer patients. The TLN is marked with various markers prior to NACT. Given the inadequate accuracy of clinical assessment of axillary lymph node status after NACT, it should be questioned whether axillary dissection after NACT should be performed based on clinical assessment of nodal status alone.

Results of shared learning of a new magnetic seed localisation device – A UK iBRA-NET breast cancer localisation study

IntroductionShared learning is imperative in the assessment and safe implementation of new healthcare interventions. Magnetic seeds (Magseed®) potentially offer logistical benefit over wire localisation for non-palpable breast lesions but few data exist on outcomes comparing these techniques. A national registration study (iBRA-NET) was conducted to collate device outcomes. In order to share learning, thematic analysis was conducted to ascertain early clinical experiences of Magseed® and wire guided localisation and explore how learning events may be applied to improve clinical outcomes. MethodsA qualitative study of 27 oncoplastic surgeons, radiologists and physicians was conducted in January 2020 to ascertain the feasibility and challenges associated with Magseed® versus wire breast localisation surgery. Four focus groups were asked to discuss experiences, concerns and shared learning outcomes which were tabulated and analysed thematically. ResultsThree key themes were identified comparing Magseed® and wire localisation of breast lesions relating to preoperative, intraoperative and postoperative learning outcomes. Percutaneous Magseed® detection, instrument interference and potential seed or wire dislodgement were the most common issues identified. Clinician experience suggested Magseed® index lesion identification was non-inferior to wire placement and improved the patient pathway in terms of scheduling and multi-site insertion. ConclusionsProspective shared learning suggested Magseed® offered additional non-clinical benefits over wire localisation, improving the efficiency of the patient pathway. Recommendations for improving breast localisation technique, appropriate patient selection and clinical practice through shared learning are discussed that may aid other surgeons in the adoption of this relatively new technique.

Preparation of Fe3O4@C with water treatment residuals and its potential in the magnetic coagulation process

The resource utilization of water treatment residuals is a hot topic in current research. In this work, a kind of carbon-doped magnetic nanoparticle (Fe 3 O 4 @C) was prepared using backwashing iron mud from the groundwater treatment plant as raw material. The Fe 3 O 4 @C was used for the magnetic coagulation (MC) process to evaluate the superiority of the MC process via comparing it with the traditional coagulation (TC) process. Meanwhile, the Fe 3 O 4 was also used for reference in the MC process to assess the potential and feasibility of the Fe 3 O 4 @C. The synthesized Fe 3 O 4 @C was characterized by SEM, TEM , XRD , VSM , and XPS . Then, coagulation performances and flocs properties were evaluated in both TC and MC processes. In addition, the various roles of magnetic particles in the MC process were discussed. The results showed that the participation of Fe 3 O 4 @C increased the turbidity removal rate from 90.3% to 96.8%, the ultra-violet absorbance at 254 nm (UV 254 ) removal rate from 81.4% to 86.5%, the dissolved organic carbon (DOC) removal rate from 60.4% to 66.9%, and the residual Al content dropped from 2.54 mg/L to 2.07 mg/L. Especially, it is found the Fe 3 O 4 @C had the potential to remove more small molecular weight organic matter during the coagulation process. The flocs were loose and easily broken due to the formation of the Al species-nanoparticle cluster. Fe 3 O 4 @C involved MC process can achieve the same water treatment efficiency as Fe 3 O 4 involved MC process, or even better. Especially, the magnetic seed of Fe 3 O 4 @C based on waste utilization can not only reduce the cost, but also has a good adsorption on small molecular organics. This provides a new reference way for the utilization of iron mud and the development of magnetic seed in the MC process. • Carbon-doped magnetic nanoparticles (Fe 3 O 4 @C) were prepared as magnetic seeds. • Fe 3 O 4 @C could improve the removal of small molecular organics by adsorption. • Recycle utilization of iron sludge was realized.

Primordial magnetic fields in theories of gravity with non-minimal coupling between curvature and matter

The existence of magnetic fields in the universe is unmistakable. They are observed at all scales from stars to galaxy clusters. However, the origin of these fields remains enigmatic. It is believed that magnetic field seeds may have emerged from inflation, under certain conditions. This possibility is analised in the context of an alternative theory of gravity with non-minimal coupling between curvature and matter. We find, through the solution of the generalised Maxwell equations in the context of non-minimal models, that for general slow-roll inflationary scenarios with low reheating temperatures, $T_{RH}\simeq10^{10}$GeV, the generated magnetic fields can be made compatible with observations at large scales, $\lambda \sim 1 Mpc$.

Structural ordering at magnetic seeds with twins at boundaries of a core–shell alloy Mn60Bi40 and tailored magnetic properties

A spin Mn3d5-rich Mn60Bi40 alloy reveals a model system in order to tailor profound magnetic properties at unpaired 3d5 spins in such alloys of a core–shell structure. As annealed (at a critical temperature 573 K in H2 gas), a refined powder (in glycine) grows on α-MnBi seeds (crystallites) present in it at Mn/Bi atoms order over topological layers, preferentially along (110) planes, at a self-confined structure at seeds of an anisotropic shape of hexagonal (h) plates (25–85 nm widths). In terms of the HRTEM images, the atoms turn down at edges (at the plates grow up) in a spiral layer, ≤ 2.1 nm thickness, of small core–shells. A spin model is proposed to delineate a way at the spins can pin down at the edges, form single magnetic domains, and raise coercivity (H c), with no much loss of net magnetic moment. The X-ray diffraction and HRTEM images corroborate the results of topological pacing of atoms at the h-plates at anneals. A novelty is that a core–shell leads to tailor a superb H c, as much as 11.110 kOe (16.370 kOe at 350 K), with a fairly large magnetization, 76.5 emu g−1, at near 300 K. An enhanced Curie point 650.1 K (628 K at Mn50Bi50 alloy) confers a surplus 3d5-Mn spin sensitively tunes α-MnBi stoichiometry and so its final magnetic structure. A refined alloy powder so made is useful to make powerful magnets and devices in the forms of films and bonded magnets in different shapes for uses as small tools, tweezers, and other devices.

Evaluation of Axillary Lymph Node Marking with Magseed® before and after Neoadjuvant Systemic Therapy in Breast Cancer Patients: MAGNET Study.

Background Due to the high false negative rate (FNR) associated with sentinel lymph node biopsy (SLNB) after neoadjuvant systemic therapy (NAST), the standard surgical treatment for patients with an initially positive axilla and indicated for NAST is axillary lymph node dissection (ALND). To avoid unnecessary ALND, this multicenter, prospective, observational study aimed to determine the effectiveness and ease of using magnetic seeds (Magseed®) for targeted axillary dissection (TAD) when the seeds are placed before or after NAST. Materials and Methods We recruited 81 patients diagnosed with T1-T3 breast cancer, with clinically/radiologically positive nodal involvement (cN1, 75 patients with 1–3 nodes suspected nodes and 6 patients with up to 4 suspected nodes) prior to NAST. Positive nodes detected by fine-needle aspiration biopsy or core needle biopsy were marked with a stainless steel marker coil and after NAST with Magseed® prior to surgery (Post-NAST group), or directly with Magseed® before NAST (Pre-NAST group). The correlation between lymph nodes marked with Magseed® (MLNs) and sentinel lymph nodes (SLNs) was calculated based on pathologic assessment with the OSNA assay (Sysmex Corporation, Kobe) or conventional sectioning and staining techniques according to the standard protocols of each center. Results All magnetic seeds were successfully identified and retrieved in just over 10 minutes of surgery, guided by the Sentimag® magnetometer system. The overall concordance rate between MLNs and SLNs was 81.5%, and the concordance between MLNs and SLNs with metastasis was 93.8%. Metastasis was detected in 54.3% of the MLNs compared with 48.1% of SLNs. In cases that presented negative MLN and negative SLN (negative TAD), the FNR was 0%. No significant differences were found between the Post-NAST and Pre-NAST groups. Conclusions Our results validate the use of Magseed® for long-term marking of axillary lymph nodes and show that when used in combination with SLNB for TAD, a FNR of 0% can be achieved, avoiding unnecessary ALND.

Enhanced precipitation performance for treating high-phosphorus wastewater using novel magnetic seeds from coal fly ash

Magnetic coagulation is a promising approach for treating high phosphorous (high-P) wastewater by enhancing precipitation efficiency using magnetic particles. In this study, a cost-effective and environmentally friendly magnetic seed from coal fly ash (MS-CFA) was used as an alternative material for Fe3O4 magnetic seed (MS) coagulation. The potential effect of MS-CFA was explored to reduce the settling time and the dosage of coagulant aid of polyacrylamide (PAM) in treating high-phosphorous (high-P) simulated wastewater at 100 and 200 mg P/L. The physicochemical characteristics of MS-CFA were analysed through particle size distribution (20–100 μm), pore size distribution (14–30 nm), specific surface area (1.654 m2/g), X-ray diffraction (XRD), specific gravity (4.2), and magnetic induction intensity (49.8 emu/g). The characteristics met the requirements as magnetic coagulation material. MS-CFA was combined with polyaluminum chloride (PAC) and polyacrylamide (PAM) to improve phosphorous precipitation performance. The synergised magnetic coagulation effect using MS-CFA and PAM reduced the settling time of flocs to less than 1 min due to the high specific gravity. This represents a reduction of 90% of the settling time compared to the control using PAM alone (15 min) without MS-CFA. MS-CFA efficiently reduced PAM dosage by 83% and 87% for treating 100 and 200 mg P/L, respectively. The presence of PAM (1 mg/L for 100 mg P/L and 2 mg/L for 200 mg P/L) was imperative for binding the MS-CFA and flocs, hence increasing the particle size of the magnetic flocs. The characteristics of the magnetic flocs were analysed through microscopy, particle size distribution, zeta potential measurements, and magnetic induction intensity. The characteristics of the magnetic flocs confirmed that MS-CFA could be an alternative material for Fe3O4 as the magnetic seeds in the magnetic coagulation process for treating high-P wastewater.

Towards convergence of turbulent dynamo amplification in cosmological simulations of galaxies

ABSTRACT Our understanding of the process through which magnetic fields reached their observed strengths in present-day galaxies remains incomplete. One of the advocated solutions is a turbulent dynamo mechanism that rapidly amplifies weak magnetic field seeds to the order of ∼$\mu$G. However, simulating the turbulent dynamo is a very challenging computational task due to the demanding span of spatial scales and the complexity of the required numerical methods. In particular, turbulent velocity and magnetic fields are extremely sensitive to the spatial discretization of simulated domains. To explore how refinement schemes affect galactic turbulence and amplification of magnetic fields in cosmological simulations, we compare two refinement strategies. A traditional quasi-Lagrangian adaptive mesh refinement approach focusing spatial resolution on dense regions, and a new refinement method that resolves the entire galaxy with a high resolution quasi-uniform grid. Our new refinement strategy yields much faster magnetic energy amplification than the quasi-Lagrangian method, which is also significantly greater than the adiabatic compressional estimate indicating that the extra amplification is produced through stretching of magnetic field lines. Furthermore, with our new refinement the magnetic energy growth factor scales with resolution following $\propto {\Delta x}_\text{max}^{-1/2}$, in much better agreement with small-scale turbulent box simulations. Finally, we find evidence suggesting most magnetic amplification in our simulated galaxies occurs in the warm phase of their interstellar medium, which has a better developed turbulent field with our new refinement strategy.

Clinical Outcomes Using Magnetic Seeds as a Non-wire, Non-radioactive Alternative for Localization ofNon-palpable Breast Lesions.

Nonpalpable breast lesions require precise preoperative localization to facilitate negative margins with breast-conserving therapy. The traditional use of wires has several challenges including patient discomfort, wire migration, and coordination of schedules between radiology and the operating room. Radioactive seed localization overcomes some of these challenges, but radiation safety requirements have limited adoption of this technology. The authors examined their institutional experience with Magseed as an alternative technology for localization and compared outcomes with those of wire and radioactive seed localization. An institutional review board (IRB)-approved retrospective study was performed to evaluate patients who underwent excisional biopsy or segmental mastectomy after wire-guided localization (WGL), radioactive seed localization (RSL), or Magseed localization (ML). The clinical and pathologic factors of the three groups were assessed with a negative margin rate as the primary outcome measure. Of the 1835 patients in the study, 825 underwent WGL, 449 underwent RSL, and 561 underwent ML. For the patients with either multiple lesions or a large lesion that required bracketing, multiple localization devices were placed in 31% of the WGL patients, 28% of the RSL patients, and 23% of the ML patients (p = 0.006). Negative margins were achieved in 91% of the WGL patients, 89% of the RSL patients, and 89% of the ML patients (p = 0.4). Localization of non-palpable breast lesions using Magseed is a safe and effective alternative to WGL and RSL that overcomes radiation safety limitations and increases radiology and surgery scheduling efficiency.

Использование градиентного магнитного поля в предпосевной обработке семян огурца

The purpose of these studies was to develop optimal modes of magnetization of cucumber seeds when cultivated in protected soil. The research task included the study of the effect of the gradient magnetic field (GrMP) on seed sowing qualities, growth processes and photosynthetic ac-tivity of cucumber plants, and crop productivity. The experiments were carried out in 2 stages, in-cluding laboratory and greenhouse soil tests. The study used generally accepted methods of estimat-ing seed quality, observing plant growth and development, taking into account the main indicators of phenophases, forming generative organs, determining crop and product quality. By experimental method positive effect of treatment of cucumber seeds with gradient magnetic field is confirmed. Stable stability of magneto-biological effects in cucumber seedlings was observed at a seed speed of 1-2 m/s in a magnetic field and its intensity in the range of 50-150 E. Plants formed from treated seeds were characterized by higher photosynthesis productivity, a large number of female flowers compared to control. Productivity growth in experimental versions by 7.6-15.3% was due to a larger number and mass of formed fruits. Magneto-biological effects in cucumber plants were observed throughout ontogenesis and culminated in an increase in its productivity. Keywords: GRADIENT MAGNETIC FIELD (GRMP), SEED OMAGNETIZATION, GERMINATION ENERGY AND LABORA-TORY GERMINATION OF CUCUMBER SEEDS, MORPHOMETRIC SEEDLINGS, PLANT GROWTH AND DE-VELOPMENT, YIELD

Semillas radiactivas y no radiactivas como método de localización quirúrgica de las lesiones mamarias no palpables

The increasingly early diagnosis of breast disease and the more widespread use of primary systemic therapy leads to an increasing number of surgeries for non-palpable breast lesions (NPL) in clinical practice.Breast-conserving surgery often requires the use of an image-guided preoperative localization procedure, in which a device is placed within the lesion to be removed to guide the surgeon during surgery. These are patients with small, non-palpable tumors detected in the population screening mammogram, cases with significant reduction of the lesion after neoadjuvant chemotherapy and sometimes it is even necessary to mark axillary lymphadenopathies prior to systemic treatment.For decades, wire localization has been the standard for preoperative marking in breast cancer. Due to the external component of this device, extreme care must be taken not to alter its position before surgery, which is why it is placed hours before surgery and entails complex and limited flexibility in surgical programming.Intraoperative ultrasound improves this drawback but has the limitation that it can only be performed in those NPLs that have ultrasound translation. The Radioguided Occult Lesion Localization (ROLL) technique, although it is another alternative adopted by many institutions, is not without complications, among which the possibility of diffusion of the radiotracer into healthy tissue stands out.To overcome these problems, more recently, 125I radioactive seeds began to be used. Subsequently, thanks to technological advances, non-radioactive seed alternatives such as radar reflectors, magnetic seeds and radio frequency markers have emerged. These locating devices can be placed days before surgery, avoiding wire-related problems and complications. They are introduced percutaneously and identified intraoperatively using a detector device.There is no perfect intraoperative localization method for NPL excision, but fortunately, we have multiple techniques with different advantages and disadvantages that must be assessed and adapted to the center's own resources, the type of surgery, and always to the benefit of the patient.

Radioactive and non-radioactive seeds as surgical localization method of non-palpable breast lesions

The increasingly early diagnosis of breast disease and the more widespread use of primary systemic therapy leads to an increasing number of surgeries for non-palpable breast lesions (NPL) in clinical practice.Breast-conserving surgery often requires the use of an image-guided preoperative localization procedure, in which a device is placed within the lesion to be removed to guide the surgeon during surgery. These are patients with small, non-palpable tumors detected in the population screening mammogram, cases with significant reduction of the lesion after neoadjuvant chemotherapy and sometimes it is even necessary to mark axillary lymphadenopathies prior to systemic treatment.For decades, wire localization has been the standard for preoperative marking in breast cancer. Due to the external component of this device, extreme care must be taken not to alter its position before surgery, which is why it is placed hours before surgery and entails complex and limited flexibility in surgical programming.Intraoperative ultrasound improves this drawback but has the limitation that it can only be performed in those NPLs that have ultrasound translation. The Radioguided Occult Lesion Localization (ROLL) technique, although it is another alternative adopted by many institutions, is not without complications, among which the possibility of diffusion of the radiotracer into healthy tissue stands out.To overcome these problems, more recently, 125I radioactive seeds began to be used. Subsequently, thanks to technological advances, non-radioactive seed alternatives such as radar reflectors, magnetic seeds and radio frequency markers have emerged. These locating devices can be placed days before surgery, avoiding wire-related problems and complications. They are introduced percutaneously and identified intraoperatively using a detector device.There is no perfect intraoperative localization method for NPL excision, but fortunately, we have multiple techniques with different advantages and disadvantages that must be assessed and adapted to the center's own resources, the type of surgery, and always to the benefit of the patient.

Advantages of magnetic seeds compared with wires in the excision of non-palpable breast cancer. A single institution experience.

Background: In recent years, due to screening programs, and the increasing use of neoadjuvant therapy, there has been an increment in breast surgery of non-palpable lesions. Traditionally, wires have been used for guiding non-palpable breast lesions resection. Recently, several devices have been commercialized as alternatives to the classical wires, such as the magnetic seeds (Magseed®).

Accuracy of Magnetic Seed usage with multiple simultaneous placements in a single breast.

Background: The use and type of breast tumour localisation devices has expanded over the last few years. The placement of magnetic seeds (Magseed®) has been increasingly used to localise the tumour site, a concern is the ability to localise multiple tumour foci with the MagSeed without having interference affecting the retrieval

Accuracy of Magnetic Localisation device placement and retrieval in breast cancer patients from a single internationally Accredited Breast Centre in Johannesburg South Africa

Background: A variety of techniques are used in breast cancer localisation. One such technique is the placement of magnetic seeds (Magseed®). The aim of the study was to conduct a review of Magseed® placement and ease of retrieval across varying depths within the breast. This study looks at the Magseed® placement data from one radiology unit in a multi-disciplinary centre consisting of 4 radiology units over a 6 month period which sees an average of 450 newly diagnosed breast cancer patients per year and has placed 1460 seeds to date

Magnetic seeds for Targeted Axillary Dissection in Breast Cancer

Background: The de-escalation in breast cancer (BC) surgery includes reducing axillary dissection (AD). Targeted axillary dissection (TAD) is currently contemplated after complete responses with neoadjuvant chemotherapy (NCT) in initially CN1+ or in cases of early BC with limited axillary involvement that will be treated with upfront surgery.

Wire- and magnetic-seed-guided localization of impalpable breast lesions: iBRA-NET localisation study.

Wire localization is historically the most common method for guiding excision of non-palpable breast lesions, but there are limitations to the technique. Newer technologies such as magnetic seeds may allow some of these challenges to be overcome. The aim was to compare safety and effectiveness of wire and magnetic seed localization techniques. Women undergoing standard wire or magnetic seed localization for non-palpable lesions between August 2018 and August 2020 were recruited prospectively to this IDEAL stage 2a/2b platform cohort study. The primary outcome was effectiveness defined as accurate localization and removal of the index lesion. Secondary endpoints included safety, specimen weight and reoperation rate for positive margins. Data were accrued from 2300 patients in 35 units; 2116 having unifocal, unilateral breast lesion localization. Identification of the index lesion in magnetic-seed-guided (946 patients) and wire-guided excisions (1170 patients) was 99.8 versus 99.1 per cent (P = 0.048). There was no difference in overall complication rate. For a subset of patients having a single lumpectomy only for lesions less than 50 mm (1746 patients), there was no difference in median closest margin (2 mm versus 2 mm, P = 0.342), re-excision rate (12 versus 13 per cent, P = 0.574) and specimen weight in relation to lesion size (0.15 g/mm2versus 0.138 g/mm2, P = 0.453). Magnetic seed localization demonstrated similar safety and effectiveness to those of wire localization. This study has established a robust platform for the comparative evaluation of new localization devices.