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Motivated by the booming development of spintronics based on quantum dot systems, we employed the standard nonequilibrium Green's function theory to derive the transport formula and the heat generation formula of a quantum dot coupled to a substrate and study the relation between spin current and its accompanying heating or cooling. Our results demonstrate that (i) a thermal bias combined with Zeeman splitting can generate steady spin current in a limited dot level range, while a rotating magnetic field can generate time-average spin current in a global range and pure spin current can induce more heat generation than non-pure spin current; (ii) magnetic resonance of spin current can also effectively enhance heat generation; (iii) appropriate environmental temperature in conjunction with a thermal bias makes cooling, while increasing the frequency of the rotating magnetic can easily give rise to the transition from cooling to heating; and (iv) enhancing the coupling between quantum dots and substrates can effectively reduce heat generation while maintaining the fundamental properties of pure spin current. [ABSTRACT FROM AUTHOR]

We report device-level damping measurements using spin-torque driven ferromagnetic resonance on perpendicular magnetic random-access memory cells. It is shown that thermal agitation enhances the apparent damping for cells smaller than about 55 nm. The effect is fundamental and does not reflect a true damping increase. In addition to the thermal effect, it is still found that device-level damping is higher than film-level damping and increases with decreasing cell size. This is attributed to edge damage caused by device patterning. [ABSTRACT FROM AUTHOR]

We implanted Fe+ ions in nanodiamond (ND) powder containing negatively charged nitrogen-vacancy (NV−) centers and studied their Raman spectra and optically detected magnetic resonance (ODMR) in various applied magnetic fields with green light (532 nm) excitation. In Raman spectra, we observed a blue shift of the NV− peak associated with the conversion of the electronic sp3 configuration to the disordered sp2 one typical for the carbon/graphite structure. In the ODMR spectra, we observed a red shift of the resonance position caused by local heating by an absorptive environment that recovers after annealing. To reveal the red shift mechanism in ODMR, we created a controlled absorptive environment around ND by adding iron-based Fe2O3 and graphitic sp2 powders to the ND suspension. This admixture caused a substantial increase in the observed shift proportional to the applied laser power, corresponding to an increase in the local temperature by 150–180 K. This surprisingly large shift is absent in non-irradiated NV-ND powders, is associated only with the modification of the local temperature by the absorptive environment of NV-NDs, and can be studied using ODMR signals of NV−. [ABSTRACT FROM AUTHOR]

Electron spin resonance pulsed dipolar spectroscopy (PDS) has become popular in protein 3D structure analysis. PDS studies yield distance distributions between a pair or multiple pairs of spin probes attached to protein molecules, which can be used directly in structural studies or as constraints in theoretical predictions. Double-quantum coherence (DQC) is a highly sensitive and accurate PDS technique to study protein structures in the solid state and under physiologically relevant conditions. In this work, we have derived analytical expressions for the DQC signal for a system with N-dipolar coupled spin-1/2 particles in the solid state. The expressions are integrated over the relevant spatial parameters to obtain closed form DQC signal expressions. These expressions contain the concentration-dependent "instantaneous diffusion" and the background signal. For micromolar and lower concentrations, these effects are negligible. An approximate analysis is provided for cases of finite pulses. The expressions obtained in this work should improve the analysis of DQC experimental data significantly, and the analytical approach could be extended easily to a wide range of magnetic resonance phenomena. [ABSTRACT FROM AUTHOR]

The study and modeling of water exchange in complex media using different applications of diffusion and relaxation magnetic resonance (MR) have been of interest in recent years. Most models attempt to describe this process using a first order kinetics expression, which is appropriate to describe chemical exchange; however, it may not be suitable to describe diffusion-driven exchange since it has no direct relationship to diffusion dynamics of water molecules. In this paper, these limitations are addressed through a more general exchange expression that does consider such important properties. This exchange fraction expression features a multi-exponential recovery at short times and a mono-exponential decay at long times, both of which are not captured by the first order kinetics expression. Furthermore, simplified exchange expressions containing partial information of the analyzed system's diffusion and relaxation processes and geometry are proposed, which can potentially be employed in already established estimation protocols. Finally, exchange fractions estimated from simulated MR data and derived here were compared, showing qualitative similarities but quantitative differences, suggesting that the features of the derived exchange fraction in this paper can be partially recovered by employing an existing estimation framework. [ABSTRACT FROM AUTHOR]

We combine micromagnetic simulations and nitrogen-vacancy (NV) defect center spin relaxometry measurements to study magnon modes in inhomogeneous spin textures. A thin, micrometer-scale ferromagnetic disk is magnetized in a vortex state in which the magnetization curls around a central core. Micromagnetic simulations show that at zero applied field, the magnetization dynamics of the disk consist of a low frequency gyrotropic mode and higher frequency azimuthal magnon modes, all far detuned from the NV spin transition frequencies. An in-plane static magnetic field breaks the azimuthal symmetry of the vortex state, resulting in the magnon modes transforming in frequency and spatial profile as the field increases. Experimentally, we probe the dynamics of vortex magnetization as a function of applied in-plane static field and ac driving frequency by optically monitoring a nearby NV defect center spin. At certain values of the applied magnetic field, we observe enhanced spin relaxation when driving at twice the frequency of the NV ground state spin transition in optically detected magnetic resonance measurements. We attribute this effect to parallel pumping of a magnon mode in the disk producing magnons at half the excitation frequency. Micromagnetic simulations support this finding, showing spatial and spectral overlap of a confined magnon mode and an NV spin transition, with sufficient interaction strength to explain the observed signal. [ABSTRACT FROM AUTHOR]

The nitrogen-vacancy (NV) center is a promising candidate to realize practical quantum sensors with high sensitivity and high spatial resolution at room temperature and atmospheric pressure. In conventional high-frequency AC magnetometry with NV centers, the setup requires a pulse sequence with an appropriate time synchronization and strong microwave power. To avoid these practical difficulties, AC magnetometry using continuous-wave optically detected magnetic resonance (CW-ODMR) was recently demonstrated. That previous study utilized radio frequency (RF)-dressed states generated by the coherent interaction between the electron spin of the NV center and the RF wave. However, the drawback of this method is that the detectable frequency of the AC magnetic fields is fixed. Here, we propose and demonstrate frequency-tunable magnetic field sensing based on CW-ODMR. In the new sensing scheme, we obtain RF double-dressed states by irradiation with RF fields at two different frequencies. One creates the RF-dressed states and changes the frequency of the target AC field. The other is a target AC field that induces a change in the CW-ODMR spectrum by generating the RF double-dressed states through coherent interaction with the RF-dressed states. The sensitivity of our method is estimated to be comparable to or even higher than that of the conventional method based on the RF field with a single frequency. The estimated bandwidth is 7.5 MHz, higher than that of the conventional method using the RF-dressed states. Our frequency-tunable magnetic field sensor based on CW-ODMR paves the way for new applications in diamond devices. [ABSTRACT FROM AUTHOR]

Optical metamaterials, sensing, nonlinear optics, and surface-enhanced spectroscopies have witnessed the remarkable potential of the anapole mode. While dielectric particles with a high refractive index have garnered significant attention in recent years, the exploration of plasmonic anapole modes with intense localized electric field enhancements in the visible frequency range remains limited. In this study, we present a theoretical investigation on the relationship between the strongest near-field response and magnetic anapole modes, along with their substantial enhancement of Raman signals from probing molecules. These captivating findings arise from the design of a practical metallic oblate spheroid–film plasmonic system that generates magnetic anapole resonances at frequencies within the visible–near-infrared range. This research not only sheds light on the underlying mechanisms in a wide range of plasmon-enhanced spectroscopies but also paves the way for innovative nano-device designs. [ABSTRACT FROM AUTHOR]

Owing to magnetoelastic coupling, surface acoustic waves (SAWs) may be scattered resonantly by magnetic elements, such as nickel stripes. The scattering may be further enhanced via the Borrmann effect when the elements are organized into an array that matches the acoustic wavelength. We use finite-element modeling to consider single- and double-layer stripes patterned on top of a lithium niobate surface that carries Love surface waves. We do observe enhancement in the coupling for single-layer stripes, but only for Gilbert damping below its realistic value. For double-layered stripes, a weak yet clear and distinct signature of Bragg reflection is identified far away from the acoustic band edge, even for a realistic damping value. Double-layered stripes also offer better magnetic tunability when their magnetic period is different from the periodicity of elastic properties of the structure because of staggered magnetization patterns. The results pave the way for the design of magnetoacoustic metamaterials with an enhanced coupling between propagating SAWs and local magnetic resonances and for the development of reconfigurable SAW-based circuitry. [ABSTRACT FROM AUTHOR]

We demonstrate a real-time, single-shot vector magnetic measurement technique using synchronous coherent population trapping (SCPT) in an apparatus consisting of a small rubidium vapor cell. Vector modality of our magnetometer is enabled by designing a feedback system based on performing a peak-lock on a particularly strong 2 Ω L magnetic resonance produced in the SCPT spectrum and compensating the external magnetic field via a three-axis field coil. With its current design, this magnetometer exhibits high sensitivities of approximately 155 , 129 , and 57 pT / Hz in measuring the magnetic field vector components along the (x,y,z) axes. Sensitivities closer to the shot-noise limit can be achieved in the future by reducing the technical noise of our equipment and by employing a differential detection and polarization rotation measurement scheme in our system. [ABSTRACT FROM AUTHOR]

Incorporating magnetic ions into semiconductor nanocrystals has emerged as a prominent research field for manipulating spin-related properties. The magnetic ions within the host semiconductor experience spin-exchange interactions with photogenerated carriers and are often involved in the recombination routes, stimulating special magneto-optical effects. The current account presents a comparative study, emphasizing the impact of engineering nanostructures and selecting magnetic ions in shaping carrier–magnetic ion interactions. Various host materials, including the II–VI group, halide perovskites, and I–III–VI2 in diverse structural configurations such as core/shell quantum dots, seeded nanorods, and nanoplatelets, incorporated with magnetic ions such as Mn2+, Ni2+, and Cu1+/2+ are highlighted. These materials have recently been investigated by us using state-of-the-art steady-state and transient optically detected magnetic resonance (ODMR) spectroscopy to explore individual spin-dynamics between the photogenerated carriers and magnetic ions and their dependence on morphology, location, crystal composition, and type of the magnetic ion. The information extracted from the analyses of the ODMR spectra in those studies exposes fundamental physical parameters, such as g-factors, exchange coupling constants, and hyperfine interactions, together providing insights into the nature of the carrier (electron, hole, dopant), its local surroundings (isotropic/anisotropic), and spin dynamics. The findings illuminate the importance of ODMR spectroscopy in advancing our understanding of the role of magnetic ions in semiconductor nanocrystals and offer valuable knowledge for designing magnetic materials intended for various spin-related technologies. [ABSTRACT FROM AUTHOR]

Real-time monitoring and quantitative measurement of molecular exchange between different microdomains are useful to characterize the local dynamics in porous media and biomedical applications of magnetic resonance. Diffusion exchange spectroscopy (DEXSY) is a noninvasive technique for such measurements. However, its application is largely limited by the involved long acquisition time and complex parameter estimation. In this study, we introduce a physics-guided deep neural network that accelerates DEXSY acquisition in a data-driven manner. The proposed method combines sampling pattern optimization and physical parameter estimation into a unified framework. Comprehensive simulations and experiments based on a two-site exchange system are conducted to demonstrate this new sampling optimization method in terms of accuracy, repeatability, and efficiency. This general framework can be adapted for other molecular exchange magnetic resonance measurements. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) power devices are becoming central components in high voltage electronics. However, defects at interfaces and in the bulk continue to severely impact their reliability and performance. Here, we develop a charge pumping method to characterize SiC/SiO 2 interface defects in fully fabricated commercial SiC power metal–oxide–semiconductor field-effect transistors (MOSFETs). The method is then used to address spin states at the SiC/SiO 2 interface via charge pumping electrically detected magnetic resonance (CP-EDMR). We apply these methods to investigate the power MOSFET after electron irradiation over a dose range of 10 13 − 10 17 cm − 2 . We finally discuss CP-EDMR as a technique to interrogate spins during device operation for real-time monitoring of the device quality, performance, and degradation and as a probe for local magnetic fields. [ABSTRACT FROM AUTHOR]

Medical image processing generally contains high components of noise produced by interference, compression and use of imperfect instrument during acquisition or transmission. An effective imaging devicei.e. Magnetic Resonance Imagingmay diagnose the disease by acute analysis of dissectional anatomical soft tisses of human. In general, MR images are of poor contrast in lieu of blurriness, out of focused and lack of brightness iside the machine. In this paper, hybridization approaches i.e. Median-Wiener filter (MW), Wiener-Median filter (WM) and other combinations like WMWM & MWMW are proposed for MR image enhancement. The results are further compared with various filtering algorithms i.e. Average filter, Median Filter, Wiener Filter &Gaussian filter and in terms of MSE, PSNR, RMSE, MAE. The proposed hybridization filtering technique gives better outcomes comparatively. [ABSTRACT FROM AUTHOR]

Alterations in pH are a hallmark in several pathologies including cancer, ischemia, and inflammation. Non-invasive magnetic resonance methods to measure pH offer a new approach for early diagnosis of diseases characterized by acid–base imbalances. The hyperpolarization with parahydrogen-induced polarization (PHIP) enhances inherently low signals in magnetic resonance experiments by several orders of magnitude and offers a suitable platform to obtain biocompatible markers in less than one minute. Here, we present an optimized preparation of an hyperpolarized H13CO3−/13CO2 pH sensor via non-enzymatic decarboxylation with H2O2 of [1-13C]pyruvate-d3 obtained by PHIP at 7 T. An improved 13C polarization of purified [1-13C]pyruvate-d3 in water with 36.65 ± 0.06% polarization was obtained starting from 50 mM precursor. Subsequent decarboxylation, H13CO3−/13CO2 exhibited 12.46 ± 0.01% of polarization at physiological pH, 45 seconds after the reaction start. Considering the dilution factor that [1-13C]pyruvate-d3 exhibits in vivo, we optimized our methodology to test the accuracy of the pH sensor at single digit millimolar concentration. In vitro pH estimations on phantoms and cell culture media demonstrated accurate pH calculations with uncertainties of less than 0.08 units. These promising results highlight the efficiency of a pH sensor generated via PHIP in less than one minute, with remarkable polarization, and biocompatibility suitable for future in vivo studies. [ABSTRACT FROM AUTHOR]

Alterations in pH are a hallmark in several pathologies including cancer, ischemia, and inflammation. Non-invasive magnetic resonance methods to measure pH offer a new approach for early diagnosis of diseases characterized by acid–base imbalances. The hyperpolarization with parahydrogen-induced polarization (PHIP) enhances inherently low signals in magnetic resonance experiments by several orders of magnitude and offers a suitable platform to obtain biocompatible markers in less than one minute. Here, we present an optimized preparation of an hyperpolarized H13CO3−/13CO2 pH sensor via non-enzymatic decarboxylation with H2O2 of [1-13C]pyruvate-d3 obtained by PHIP at 7 T. An improved 13C polarization of purified [1-13C]pyruvate-d3 in water with 36.65 ± 0.06% polarization was obtained starting from 50 mM precursor. Subsequent decarboxylation, H13CO3−/13CO2 exhibited 12.46 ± 0.01% of polarization at physiological pH, 45 seconds after the reaction start. Considering the dilution factor that [1-13C]pyruvate-d3 exhibits in vivo, we optimized our methodology to test the accuracy of the pH sensor at single digit millimolar concentration. In vitro pH estimations on phantoms and cell culture media demonstrated accurate pH calculations with uncertainties of less than 0.08 units. These promising results highlight the efficiency of a pH sensor generated via PHIP in less than one minute, with remarkable polarization, and biocompatibility suitable for future in vivo studies. [ABSTRACT FROM AUTHOR]

Parotid glands are one of the most common sites for salivary gland tumors. Conventional imaging techniques have limited usefulness in the quantitative assessment of the parotid glands, making it difficult to differentiate between healthy tissue and tumors, as well as between benign and malignant tumors. Magnetic resonance elastography (MRE) is a non-invasive technique that may potentially overcome these limitations. Nevertheless, due to the size of the parotid gland, increased elastographic resolution is required. This may be achieved by applying shear waves at higher frequencies. However, it also results in stronger attenuation, making the illumination of the parotid challenging. Here, we describe a novel passive driver tailored to the anatomy of the human face, which minimizes the distance shear waves need to travel from the source to the area of interest and thus decreases shear wave attenuation, making high-frequency shear wave MRE feasible. [ABSTRACT FROM AUTHOR]

We aimed to compare the accuracy and reliability of two segmentation tools for magnetic resonance (MR) volumetry (FreeSurfer and Neurophet AQUA) at two magnetic field strengths (1.5T and 3T). We included 101 patients for the 1.5T–3T dataset and 112 for the 3T–3T dataset from three hospitals and five open-source datasets. The mean volume difference and average volume difference percentage with the change in magnetic field strength were compared between the methods. The hippocampus volume was larger with FreeSurfer than the Neurophet AQUA. In most brain regions, the Neurophet AQUA yielded a smaller average volume difference percentage (all < 10%) than FreeSurfer (all > 10%). The Neurophet AQUA exhibited more stable connectivity and regularity of the segmented components. Regarding volume, the Neurophet AQUA had effect sizes and ICCs comparable to those of FreeSurfer across the magnetic field strengths. With FreeSurfer, the original volume difference was small, whereas the average volume difference percentage was small with the Neurophet AQUA. Image segmentation took 1 h with FreeSurfer and 5 min with the Neurophet AQUA. When choosing an automatic segmentation method, the differences in image processing time and volume variability due to changes in the magnetic field strength of these methods should be considered. [ABSTRACT FROM AUTHOR]

Background Methods Results Interpretation Previous studies have observed liver abnormalities in amyotrophic lateral sclerosis (ALS) patients. This study aimed to investigate whether early signs of liver disease, measured by magnetic resonance imaging‐derived iron‐corrected T1‐mapping (cT1), are risk factors for developing ALS.cT1 and proton density fat fraction were measured and automatically analyzed using LiverMultiScan® software. The Fibrosis‐4 index was calculated using an established formula based on age and blood markers. Cox proportional hazard models were used to examine the relationship between liver disease, liver biomarkers, and incident ALS.In a cohort of 533,707 individuals from UK Biobank, 24 ALS cases were identified among 28,328 participants with liver disease during the follow‐up period. Among a total of 33,959 individuals with complete liver imaging data, 15 incident ALS cases were observed during a median follow‐up period of 5.6 years. Individuals with liver disease had a higher risk of developing ALS, with an adjusted hazard ratio of 7.35 (95% CI 4.47–12.09; p < 0.001). An increase in cT1 was also associated with a higher risk of ALS. After adjusting for age, sex, Townsend deprivation index, smoking status, alcohol intake frequency, body mass index, proton density fat fraction, Fibrosis‐4, and metabolic syndrome, an increase in cT1 remained significantly associated with a higher risk of ALS, with an adjusted hazard ratio of 3.15 (95% CI 1.79–5.55) per 1‐SD increase. Sensitivity analyses confirmed these robust results.Liver disease activity, indicated by cT1, increases the risk of developing ALS, independent of metabolic syndrome, liver fat, or fibrosis. ANN NEUROL 2024 [ABSTRACT FROM AUTHOR]

Thoracic hernias encompass the protrusion of thoracic contents through the thorax or intra‐abdominal tissue into the thorax. They can be classified as diaphragmatic hernias – either congenital or acquired; pulmonary hernias – involving tissue protrusion through cervical fascia or intercostal spaces; and mediastinal hernias – including cardiac, intrapericardial and hiatal hernias. Prompt identification and classification of thoracic hernias rely on diagnostic imaging, primarily through computed tomography and magnetic resonance, to identify associated complications. This article comprehensively reviews thoracic hernias and their key imaging features. [ABSTRACT FROM AUTHOR]

[Display omitted] • Functional neuroimaging alterations in AOID patients with anxiety. • Correlations analysis support neural basis of anxiety symptoms in AOID. • Candidate imaging biomarkers to distinguish AOID patients with/without anxiety. Psychiatric disturbances are commonly associated with adult-onset isolated dystonia (AOID); however, the mechanisms underlying psychiatric abnormalities in AOID remain unknown. We aimed to investigate the structural and functional brain changes in AOID patients with anxiety, and identify imaging biomarkers for diagnosing anxiety. Structural and functional magnetic resonance was performed on 69 AOID patients and 35 healthy controls (HCs). The Hamilton Anxiety Scale (HAMA) was used to assess anxiety symptoms in AOID patients and assign patients to AOID with and without anxiety groups. Group differences in grey matter volume, amplitude of low-frequency fluctuations (ALFF), fractional ALFF, and regional homogeneity (ReHo) were evaluated. Area under the receiver operating characteristic curve (ROC AUC) was used as a metric to identify imaging biomarkers for diagnosing anxiety. AOID patients with anxiety exhibited an increased ALFF and ReHo in the left angular gyrus (ANG.L) compared with those without and HCs (voxel P <0.001 and cluster P <0.05, corrected using GRF). A significant positive correlation was observed between ALFF (r = 0.627, P <0.001) and ReHo (r = 0.515, P <0.001) in the ANG.L and HAMA scores in AOID patients. ALFF and ReHo in the ANG.L exhibited an ROC AUC of 0.904 and 0.851, respectively, in distinguishing AOID patients with anxiety from those without and an ROC AUC of 0.887 and 0.853, respectively, in distinguishing AOID patients with anxiety from HCs. These findings provide new insights into the pathophysiology of psychiatric disturbances and highlight potential candidate biomarkers for identifying anxiety in AOID patients. [ABSTRACT FROM AUTHOR]

Defect-related spin-to-photon interfaces in silicon promise the realization of quantum repeaters by combining advanced semiconductor and photonics technologies. Recently, controlled creation/erasure of simple carbon interstitial defects have been successfully realised in silicon. This defect has a stable structure near room temperature and coherently emits in the wave-length where the signal loss is minimal in optical fibres used in communication technologies. Our in-depth theoretical characterization confirms the assignment of the observed emission to the neutral charge state of this defect, as arising due to the recombination of a bound exciton. We also identified a metastable triplet state that could be applied as a quantum memory. Based on the analysis of the electronic structure of the defect and its similarities to a known optically detected magnetic resonance centre in silicon, we propose that a carbon interstitial can act as a quantum bit and may realize a spin-to-photon interface in complementary metal-oxide semiconductor-compatible platforms. This work presents a theoretical investigation of the single carbon interstitial (Ci) defect in silicon as a potential candidate for spin-photon interfaces. Computed charge transition levels and optical properties show good agreement with the experimental results and allow assigning the experimentally observed telecom zero-phonon emission (1448 nm) to the neutral Ci defect. [ABSTRACT FROM AUTHOR]

Background: Cerebral venous sinus thrombosis has not been reported in anti-N-methyl-d-aspartate receptor-antibody encephalitis in the absence of an underlying thrombotic state while rituximab induced cerebral venous sinus thrombosis is rarely reported. We report a patient with anti-N-methyl-d-aspartate receptor-antibody encephalitis without a prothrombotic state who developed cerebral venous sinus thrombosis following rituximab treatment. Case presentation: A 15-year-old Sri Lankan girl who had been in remission following an episode of anti-N-methyl-d-aspartate receptor-antibody encephalitis 2 years ago, presented with a relapse of anti-N-methyl-d-aspartate receptor-antibody encephalitis characterized by recurrent seizures, mutism, and cognitive abnormalities. Since response was inadequate to first-line immunotherapy, she was administered four doses of rituximab at weekly intervals. Two days after the fourth dose, she developed increasing headaches, and her cranial magnetic resonance venogram confirmed the development of cerebral venous sinus thrombosis. Screening for prothrombotic states were negative. She made an unremarkable recovery following anticoagulation. Conclusion: This case highlights the occurrence of the rare but serious complication of cerebral venous sinus thrombosis following rituximab in the context of anti-N-methyl-d-aspartate receptor-antibody encephalitis and informs the clinician to be wary of new onset headache in patients with anti-N-methyl-d-aspartate receptor-antibody encephalitis treated with immunotherapy. [ABSTRACT FROM AUTHOR]

Objectives:Methods:Results:Conclusions:Hearing implants often limit the assessment of magnetic resonance examinations due to susceptibility artefacts. Our aim was to evaluate the impact of artefacts attributed to the Osia®2 implant system in terms of utility in visualizing selected cranial structures.A BI300 implant and an OSI200 actuator were implanted into a human cadaver head in the audiologically most favourable position according to the manufacturer’s guidelines. Scanning was accomplished using the institutional head and inner ear protocol with a General Electric 1.5 Tesla scanner with retained and removed implant magnet, extended with T1 and T2 weighted sequences with metal-artefact reduction (MAVRIC SL). Image quality was evaluated by three radiologists.The Osia®2 produced significant artefacts in most of the series of standard imaging sequences predominantly on the ipsilateral side of the head. The majority of the artefacts were caused by the implant magnet. Even without removing the magnet, MAVRIC SL improved image quality to such an extent that it became comparable with that after magnet removal.The standard sequences suffer considerable quality loss due to the artefacts, attributed predominantly to the magnetic component. Metal-artefact reduction sequences are effective in obtaining sufficient-to-good quality images without surgical magnet removal. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Material and Methods Results Conclusion To summarize published information about the desmoplastic fibroma of the gnathic bones into a descriptive analysis of the main features of this condition.A systematic review according to the PRISMA guidelines was conducted. Electronic search was performed in four databases and in the gray literature. Case reports and case series were included. Frequencies were obtained for descriptive analysis.We identified 66 articles, for a total of 96 cases. Female patients (55.8%) in the first decade of life (40.6%) with a mean age of 18.2 years were more affected. The mandible was the most affected bone with 81.2% of the cases. The main clinical feature was painless swelling (54.2%). Most of the imaging examinations (radiological, computed tomography, and magnetic resonance) showed well‐defined radiolucencies (65.4%) lesions. The treatment was surgical removal in all cases. The recurrence rate was 10.8% and all in the posterior mandible. Spindle cell fibroblasts in a collagenized stroma were often described in the histopathological features. Vimentin, smooth muscle actin, and β‐catenin were common immunohistochemical markers.Desmoplastic fibroma is a locally aggressive lesion that commonly affects the jaws in children. Histopathology is essential for diagnosis, and the pathogenesis of this tumor should be further investigated. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Level of Evidence Chondral and osteochondral lesions in the knee are common conditions that significantly impair individuals' well‐being and can lead to osteoarthritis, imposing substantial burdens on healthcare systems. The limited natural healing capacity of articular cartilage necessitates innovative treatment strategies. Microfracture (MF) is a widely used technique for knee chondral defects, but its long‐term efficacy is often inadequate. Although recent randomised controlled trials have compared microfractures with scaffold‐enhanced therapies, a comprehensive systematic review and meta‐analysis are lacking.An extensive literature search was conducted in PubMed and EMBASE databases following PRISMA guidelines. Inclusion criteria focused on randomised controlled trials (RCTs) comparing microfractures alone to matrix‐induced chondrogenesis for knee chondral defects with at least a 12‐month follow‐up. Ten randomised controlled trials conducted between 2013 and 2024, enroling 378 patients, were included.The meta‐analysis showed no significant superiority of scaffolds over MF (p > 0.05) in International Knee Documentation Committee, Knee Injury and Osteoarthritis Outcome, Visual Analog Scale, and Magnetic Resonance Observation of Cartilage Repair Tissue scores at 12 and 24 months. However, individual studies suggested the potential benefits of scaffolds, especially in long‐term outcomes. Clinical improvements from MF typically decline after 2–3 years, underscoring the need for long‐term follow‐up in future research.Our meta‐analysis shows no significant difference between MF and MF with scaffold in treating knee cartilage defects, though some long‐term RCTs demonstrate statistically significant differences. The absence of a universally accepted algorithm for analysing knee chondral defects limits this study. Establishing reliable guidelines and standardised study protocols is essential to improve long‐term patient outcomes and the quality of future papers.Level I [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion Level of Evidence This study investigated whether age affects clinical outcomes and cartilage repair quality in patients who underwent collagen‐augmented chondrogenesis.The study included patients who underwent either the collagen‐augmented chondrogenesis technique or microfracture for cartilage defects of the knee joint of International Cartilage Repair Society grade 3 or 4. Patients were categorised according to an age threshold of 50 years and the treatment method, whether collagen‐augmented chondrogenesis technique or microfracture. Group 1 comprised 31 patients aged 50 years or older who received the collagen‐augmented chondrogenesis technique, Group 2 consisted of 32 patients under the age of 50 years who received the collagen‐augmented chondrogenesis technique and Group 3 included 243 patients aged 50 years or older who received microfracture. Clinical outcomes were assessed using the walking visual analogue scale (VAS) for pain and the Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC) two years after surgery. For patients with magnetic resonance imaging results 1 year postoperatively (Group 1: 30 patients; Group 2: 31 patients; and Group 3: 31 patients), Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) assessment was used to evaluate repaired cartilage lesions.There were no significant differences in the VAS and WOMAC scores between the three groups 2 years after surgery (all n.s.). The MOCART score in patients who underwent MRI at 1 year postoperatively showed significant differences in the degree of defect repair, integration with the border zone, surface of the repaired tissue, adhesion and total score among the three groups (all p < 0.05). Post hoc analysis revealed no difference in the total MOCART scores between Groups 1 and 2. However, Groups 1 and 2 had significantly higher MOCART scores than Group 3 1 year after surgery (all p < 0.05).The collagen‐augmented chondrogenesis technique group showed improved quality of cartilage repair compared to the microfracture group, regardless of patient age. Compared with simple microfracture treatment, there were no differences in clinical outcomes between the patient groups, related to age.Level Ⅲ. [ABSTRACT FROM AUTHOR]

Objective. Aim of this work is to illustrate and experimentally validate a model to evaluate the dielectric properties of biological tissues on a wide frequency band using the magnetic resonance imaging (MRI) technique. Approach. The dielectric behaviour of biological tissues depends on frequency, according to the so-called relaxation mechanisms. The adopted model derives the dielectric properties of biological tissues in the frequency range 10 MHz–20 GHz considering the presence of two relaxation mechanisms whose parameters are determined from quantities derived from MRI acquisitions. In particular, the MRI derived quantities are the water content and the dielectric properties of the tissue under study at the frequency of the MR scanner. Main results. The model was first theoretically validated on muscle and fat using literature data in the frequency range 10 MHz–20 GHz. Results showed capabilities of reconstructing dielectric properties with errors within 16%. Then the model was applied to ex vivo muscle and liver tissues, comparing the MRI-derived properties with data measured by the open probe technique in the frequency range 10 MHz–3 GHz, showing promising results. Significance. The use of medical techniques based on the application of electromagnetic fields (EMFs) is significantly increasing. To provide safe and effective treatments, it is necessary to know how human tissues react to the applied EMF. Since this information is embedded in the dielectric properties of biological tissues, an accurate and precise dielectric characterization is needed. Biological tissues are heterogenous, and their characteristics depend on several factors. Consequently, it is necessary to characterize dielectric properties in vivo for each specific patient. While this aim cannot be reached with traditional measurement techniques, through the adopted model these properties can be reconstructed in vivo on a wide frequency band from non-invasive MRI acquisitions. [ABSTRACT FROM AUTHOR]

Metasurfaces are established tools for manipulating light and enhancing light-matter interactions. However, the loss of conventional meta-atoms usually limits the performance potential of metasurfaces. In this study, we propose a class of metasurfaces based on discretized meta-atoms able to mitigate the radiative and intrinsic losses. By discretizing meta-atoms, we reduce the loss of metal metasurfaces to levels comparable to dielectric metasurfaces in the short-wavelength infrared region at the surface lattice resonance mode. Furthermore, we propose a coupling model to explain the observed reduction in loss in full agreement with the results obtained from finite-element method. We also reproduce this phenomenon using dielectric metasurface at electric and magnetic resonances in the visible region. Our finding offers valuable insights for the design and application of metasurfaces, while also providing theoretical implications for other resonance fields beyond metasurfaces. Metasurfaces are established tools for manipulating light and enhancing light-matter interactions, but the loss of conventional meta-atoms usually limits the performance potential of metasurfaces. Here, the authors propose a class of metasurfaces based on discretized meta-atoms able to mitigate the radiative and intrinsic losses, as interpreted by their built coupling model. [ABSTRACT FROM AUTHOR]

Objective: To assess the effectiveness of diffusion-weighted magnetic resonance imaging (DW-MRI) in the detection of non-palpable undescended testis (NPUT) and to compare DW-MRI results with surgical findings. Methods: This descriptive, cross-sectional study was carried out at Dow Institute of Radiology, Dow University of Health Sciences. Karachi on a cohort of patients who underwent DW-MRI for suspected NPUT between 15th September, 2022 to 16th March, 2023. The study included 175 boys below the age of 16 years with history of clinically non-palpable testes. MRI scans were acquired using additional DWI sequence. Two radiology faculty of more than five years of experience independently evaluated the DW-MRI images for the presence or absence of testes in its normal anatomical position, abnormal location, side and size of testes. Results: Out of the 175 patients, DW-MRI successfully detected 128 (73.1%) non-palpable undescended testes. Statistical analysis in clinically detected cases of showed sensitivity of NPTU 0.8%, specificity of 92.5%, diagnostic accuracy 94.29%, positive predictive value 97.7%, and negative predictive value 84.1% for localizing undescended testes with Diffusion Weighted DW-MRI taking surgical findings as gold standard. Conclusion: DWI sequences complement the conventional MRI, increasing its sensitivity and diagnostic accuracy. By facilitating early and accurate diagnosis, DW-MRI has the potential to streamline patient management, reduce unnecessary surgical exploration, and ultimately improve the long-term reproductive health and quality of life for individuals with undescended testes. [ABSTRACT FROM AUTHOR]

To compare predictive performance for pedicle screw loosening between computed tomography (CT)-based Hounsfield units (HU) and magnetic resonance imaging (MRI)-based vertebral bone quality score (VBQ) after lumbar surgery. A retrospective study was conducted on patients who received transforaminal lumbar interbody fusion continuously at our institution from May 2018 to September 2020. On the basis of 12 months' follow-up lumbar radiographs, screw loosening was defined as a clear zone of minimal thickness of ≥1 mm around the pedicle screw on radiography. VBQ score and HU value were measured using preoperative MRI and CT, respectively. Then, we evaluated the predictive performance of these 2 parameters by comparing the receiver operating characteristic curve. In all patients, area under the curve (AUC) of the VBQ score (AUC = 0.752; 95% confidence interval [CI] 0.663–0.841; P < 0.001) was larger than those of the CT HU value (AUC = 0.652; 95% CI 0.558–0.746; P = 0.005), but there was no significant difference between them (P AUC = 0.076). In patients with lumbar spinal stenosis, AUC of VBQ score (AUC = 0.863; 95% CI 0.764–0.961; P < 0.001) was larger than those of the CT HU value (AUC = 0.673; 95% CI 0.513–0.833; P = 0.043), with significant difference (P AUC = 0.003). MRI-based VBQ score and CT-based HU value have similar performance in predicting pedicle screw loosening after lumbar surgery. Furthermore, in patients with lumbar spinal stenosis, VBQ score demonstrated better predictive ability than HU value. [ABSTRACT FROM AUTHOR]

Measurement of static magnetic field (B0) homogeneity is an essential component of routine MRI system evaluation. This report summarizes the work of AAPM Task Group (TG) 325 on vendor‐specific methods of B0 homogeneity measurement and evaluation. TG 325 was charged with producing a set of detailed, step‐by‐step instructions to implement B0 homogeneity measurement methods discussed in the American College of Radiology (ACR) MRI Quality Control Manual using specific makes and models of MRI scanners. The TG produced such instructions for as many approaches as was relevant and practical on six currently available vendor platforms including details of software/tools, settings, phantoms, and other experimental details needed for a reproducible protocol. Because edits to these instructions may need to be made as vendors enter and exit the market and change available tools, interfaces, and access levels over time, the step‐by‐step instructions are published as a living document on the AAPM website. This summary document provides an introduction to B0 homogeneity testing in MRI and several of the common methods for its measurement and evaluation. A living document on the AAPM website provides vendor‐specific step‐by‐step instructions for performing these tests to facilitate accurate and reproducible B0 homogeneity evaluation on a routine basis. [ABSTRACT FROM AUTHOR]

Metabolic bone diseases (MBDs) are a diverse group of diseases, affecting the mass or structure of bones and leading to reduced bone quality. Parameters representing different aspects of bone health can be obtained from various magnetic resonance imaging (MRI) methods such as proton MR spectroscopy, as well as chemical shift encoding-based water-fat imaging, that have been frequently applied to study bone marrow in particular. Furthermore, T2* mapping and high-resolution trabecular bone imaging have been implemented to study bone microstructure. In addition, quantitative susceptibility mapping and ultrashort echo time imaging are used for trabecular and cortical bone assessment. This review offers an overview of technical aspects, as well as major clinical applications and derived main findings, for MRI-based assessment of bone quality in MBDs. It focuses on osteoporosis as the most common MBD. [ABSTRACT FROM AUTHOR]

Multilayered [Cu(3 nm)/FeNi(100 nm)]5/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/FeNi(10 nm)/Cu(150 nm)/[Cu(3 nm)/FeNi(100 nm)]5 structures were obtained by using the magnetron sputtering technique in the external in-plane magnetic field. From these, multilayer magnetoimpedance elements were fabricated in the shape of elongated stripes using the lift-off lithographic process. In order to obtain maximum magnetoimpedance (MI) sensitivity with respect to the external magnetic field, the short side of the rectangular element was oriented along the direction of the technological magnetic field applied during the multilayered structure deposition. MI sensitivity was defined as the change of the total impedance or its real part per unit of the magnetic field. The design of the elements (multilayered structure, shape of the element, etc.) contributed to the dynamic and static magnetic properties. The magnetostatic properties of the MI elements, including analysis of the magnetic domain structure, indicated the crucial importance of magnetostatic interactions between FeNi magnetic layers in the analyzed [Cu(3 nm)/FeNi(100 nm)]5 multilayers. In addition, the uniformity of the magnetic parameters was defined by the advanced technique of the local measurements of the ferromagnetic resonance field. Dynamic methods allowed investigation of the elements at different thicknesses by varying the frequency of the electromagnetic excitation. The maximum sensitivity of 40%/Oe with respect to the applied field in the range of the fields of 3 Oe to 5 Oe is promising for different applications. [ABSTRACT FROM AUTHOR]

Introduction: The IMPACT BCN trial—a parallel‐group randomized clinical trial where 1221 pregnant women at high risk for small‐for‐gestational age (SGA) newborns were randomly allocated at 19‐ to 23‐week gestation into three groups: Mediterranean diet, Mindfulness‐based Stress reduction or non‐intervention—has demonstrated a positive effect of Mediterranean diet and Stress reduction in the prevention of SGA. However, the mechanism of action of these interventions remains still unclear. The aim of this study is to investigate the effect of Mediterranean diet and Stress reduction on placental volume and perfusion. Material and Methods: Participants in the Mediterranean diet group received monthly individual and group educational sessions, and free provision of extra‐virgin olive oil and walnuts. Women in the Stress reduction group underwent an 8‐week Stress reduction program adapted for pregnancy, consisting of weekly 2.5‐h and one full‐day sessions. Non‐intervention group was based on usual care. Placental volume and perfusion were assessed in a subgroup of randomly selected women (n = 165) using magnetic resonance (MR) at 36‐week gestation. Small placental volume was defined as MR estimated volume <10th centile. Perfusion was assessed by intravoxel incoherent motion. Results: While mean MR placental volume was similar among the study groups, both interventions were associated with a lower prevalence of small placental volume (3.9% Mediterranean diet and 5% stress reduction vs. 17% non‐intervention; p = 0.03 and p = 0.04, respectively). Logistic regression showed that small placental volume was significantly associated with higher risk of SGA in both study groups (OR 7.48 [1.99–28.09] in Mediterranean diet and 20.44 [5.13–81.4] in Stress reduction). Mediation analysis showed that the effect of Mediterranean diet on SGA can be decomposed by a direct effect and an indirect effect (56.6%) mediated by a small placental volume. Similarly, the effect of Stress reduction on SGA is partially mediated (45.3%) by a small placental volume. Results on placental intravoxel incoherent motion perfusion fraction and diffusion coefficient were similar among the study groups. Conclusions: Structured interventions during pregnancy based on Mediterranean diet or Stress reduction are associated with a lower proportion of small placentas, which is consistent with the previously observed beneficial effects of these interventions on fetal growth. [ABSTRACT FROM AUTHOR]

Myocardial injury after noncardiac surgery (MINS) and perioperative myocardial injury are associated with increased morbidity and mortality. Both are diagnosed by a perioperative increase in troponin, yet there is controversy if MINS is a genuine myocardial insult. We applied postoperative cardiovascular magnetic resonance T2 mapping techniques to visualise acute myocardial injury (i.e. oedema) in six patients with multiple cardiovascular risk factors who underwent aortic surgery. The burden of myocardial oedema was substantially higher in four patients with elevated troponin qualifying for MINS, compared with patients without MINS. The data and images suggest that MINS represents genuine myocardial injury. [ABSTRACT FROM AUTHOR]

Purpose: Blood culture (BC) is the gold standard for diagnosing blood stream infections (BSI) but is limited by long turnaround times (TAT) and low detection rate. The T2 Magnetic Resonance method (T2MR) offers a rapid, culture-independent alternative. The objective of this study was to compare the performance of the T2Bacteria assay to BCs in a real-world setting. Methods: Retrospective comparative study consisting of T2Bacteria samples and BCs sampled within 72 h from the T2Bacteria sample. The primary outcome was detections by BC and T2Bacteria, respectively. The secondary outcome was difference in TAT. Results: In total, 640 episodes were included, consisting of 640 T2Bacteria samples and 2,117 BCs. A median of three BCs was collected for each T2Bacteria sample. Overall positivity was 101 (15.8%) by either method. In 29 (28.7%) episodes, both T2Bacteria and BC were concordantly positive. In discordant episodes, 46/101 (45.5%) episodes were T2Bacteria positive/BC negative and 26/101 (25.7%) were T2Bacteria negative/BC positive (McNemar χ2, p < 0,05). In T2Bacteria positive/BC negative episodes, eight had growth of the same microorganism in a non-BC culture. Median (IQR) TAT for BC was 35 h and 30 min (25 h 50 min − 45 h 24 min), compared to 21 h and 3 min (17 h 6 min − 27 h 30 m) for T2Bacteria (p < 0.001), with longer delays for samplings occurring outside work hours. Conclusions: The study highlights a high discordance between T2Bacteria and BC and suggests complementary roles of the methods in BSI diagnostics. Furthermore, it is crucial to improve TAT by reducing preanalytical delays. [ABSTRACT FROM AUTHOR]

Adeno-associated virus (AAV) is a clinically useful gene delivery vehicle for treating neurological diseases. To deliver AAV to focal targets, direct infusion into brain tissue by convection-enhanced delivery (CED) is often needed due to AAV's limited penetration across the blood-brain-barrier and its low diffusivity in tissue. In this study, computational models that predict the spatial distribution of AAV in brain tissue during CED were developed to guide future placement of infusion catheters in recurrent brain tumors following primary tumor resection. The brain was modeled as a porous medium, and material property fields that account for magnetic resonance imaging (MRI)-derived anatomical regions were interpolated and directly assigned to an unstructured finite element mesh. By eliminating the need to mesh complex surfaces between fluid regions and tissue, mesh preparation was expedited, increasing the model's clinical feasibility. The infusion model predicted preferential fluid diversion into open fluid regions such as the ventricles and subarachnoid space (SAS). Additionally, a sensitivity analysis of AAV delivery demonstrated that improved AAV distribution in the tumor was achieved at higher tumor hydraulic conductivity or lower tumor porosity. Depending on the tumor infusion site, the AAV distribution covered 3.67–70.25% of the tumor volume (using a 10% AAV concentration threshold), demonstrating the model's potential to inform the selection of infusion sites for maximal tumor coverage. [ABSTRACT FROM AUTHOR]

• Found the high-risk factors of PAS patients successfully. • Found the independent risk factors for the occurrence of PAS. • Construct a prediction model of PAS which had great clinical prediction value. To investigate the risk factors affecting patients with placenta previa (PP) and to construct an effective prediction model for the severity of PAS in PP. A total of 240 pregnant women with PP were enrolled in this study. An MRI+Ultrasound-based model was developed to classify patients into placental implantation and non-placental implantation groups. Multivariate nomograms were created based on imaging features. The model was evaluated using Receiver Operating Characteristic (ROC) curve analysis. The predictive accuracy of the nomogram was assessed through calibration plots and decision curve analysis. The MRI+Ultrasound-based prediction model demonstrated favorable discrimination between the placental implantation and non-placental implantation groups. The calibration curve exhibited agreement between the estimated and actual probability of placental implantation. Additionally, decision curve analysis indicated a high clinical benefit across a wide range of probability thresholds. The Area under the ROC curve (AUC) was 0.911 (95 % CI: 0.76–0.947), with a sensitivity of 88.40 % and specificity of 88.10 %. The MRI+Ultrasound-based prediction model could be a valuable tool for preoperative prediction of the percentage of implantation. Our study enables obstetricians to conduct more adequate preoperative evaluations. [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study was to assess the possible benefits of Therapeutic Magnetic Resonance (TMR) in the treatment of spontaneous perineal lacerations and episiotomies in the postpartum. Methods: We performed a prospective, non-pharmacologic, non-profit, monocentric interventional study on women who had a spontaneous laceration and/or an episiotomy at delivery. The TMR device treatment was accepted by 52 women, while 120 women underwent standard care. Patients were visited 1 day postpartum, before starting the treatment; then a follow-up visit was performed at 3 weeks, 5 weeks, and 3 months after delivery. The main endpoint was the time required for complete healing of the laceration and/or the episiotomy. Secondary endpoints were the prevalence of dehiscence, infections, urinary discomfort, urinary leakage, and the quality of restoration of sexual function. Results: In the treatment group the REEDA score was significantly better both at 3- and 5-weeks postpartum follow-up. At 3 weeks and 5 weeks postpartum, we observed a significantly better outcome in the treatment group for all subjective complaints and perineal complications associated with lacerations and episiotomies. The percentage of patients who scored above the cutoff for sexual dysfunction was significantly better in the treatment group (83.3%) than in the control group (31.8%) (p < 0.001). Conclusions: With this pilot study, we introduced low dose Pulsating Electromagnetic Fields (PEMFs) as a novel conservative and not pharmacological approach to reduce complications of perineal lesions. Our results demonstrated to significantly improve perineal wound healing and to ameliorate the sexual function in the postpartum. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the renal fat deposition on Dixon-based magnetic resonance imaging (MRI) and to explore the predictive value of renal fat biomarkers of magnetic resonance (MR-RFBs) for early kidney damage in obesity. Methods: This prospective study included 56 obese volunteers and 47 non-obese healthy volunteers. All volunteers underwent renal magnetic resonance examinations. The differences in MR-RFBs [including renal proton density fat fraction (PDFF), renal sinus fat volume (RSFV), and perirenal fat thickness (PRFT)] measured on Dixon-based MRI between the obese and non-obese volunteers were analyzed using a general linear model, taking sex, age, diabetes, and hypertension as covariates. The relationship between estimated glomerular filtration rate (eGFR) and demographic, laboratory, and imaging parameters in obese volunteers was examined by correlation analysis. Results: Obese volunteers had higher MR-RFBs than non-obese volunteers after controlling for confounders (all p < 0.001). Renal PDFF (r = − 0.383; p = 0.004), RSFV (r = − 0.368; p = 0.005), and PRFT (r = − 0.451; p < 0.001) were significantly negatively correlated with eGFR in obesity. After adjusting for age, sex, body mass index, diabetes, hypertension, visceral adipose tissue, subcutaneous adipose tissue, renal PDFF, and RSFV, PRFT remained independently negatively associated with eGFR (β = − 0.587; p = 0.003). Conclusions: All MR-RFBs are negatively correlated with eGFR in obesity. The MR-RFBs, especially PRFT, may have predictive value for early kidney damage in obesity. [ABSTRACT FROM AUTHOR]

Multi‐exponential decay is prevalent in magnetic resonance spectroscopy, relaxation, and imaging. This paper describes simple MATLAB and Python functions and scripts for regularized multi‐exponential analysis methods for 1D and 2D data and example test problems and experiments. Regularized least‐squares solutions provide production‐quality outputs with robust stopping rules in ~5 and ~20 lines of code for 1D and 2D inversions, respectively. The software provides an open‐architecture simple solution for transforming exponential decay data to the distribution of their decay lifetimes. Examples from magnetic resonance relaxation of a complex fluid, a Danish North Sea crude oil, and fluid mixtures in porous materials—brine/crude oil mixture in North Sea reservoir chalk—are presented. Developed codes may be incorporated in other software or directly used by other researchers, in magnetic resonance relaxation, diffusion, and imaging or other physical phenomena that require multi‐exponential analysis. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the technique of DCMRL to identify central lymphatic abnormalities in patients with primary lymphatic anomalies and discuss utility of the findings. Twenty-eight patients with primary lymphatic abnormalities underwent dynamic magnetic resonance imaging (MRI) following injection of gadolinium directly into inguinal lymph nodes at a tertiary lymphovascular referral center. Technical success was achieved in 23 patients (82.1%). Pathological imaging findings included obstructed, hypoplastic, or absent lymphatic channels with collateralization/rerouting or reflux of flow, lymphangiectasia, lymphatic pseudoaneurysms, and lymph leaks. Protocol modifications for improved imaging are highlighted including technical aspects of lymph node injection, image acquisition and MRI parameters. In two patients, imaging findings warranted embolization of the abnormal lymphatic channels with subsequent symptomatic improvement. DCMRL has been shown to be a safe, reproducible technique in patients with primary lymphatic anomalies enabling imaging of the central lymphatic system. • Central lymphatics visualized in 82.1% with dynamic contrast-enhanced intranodal magnetic resonance lymphangiography (DCMRL). • Optimizing imaging parameters and needle placement technique are critical. • DCMRL enables dynamic assessment of central lymphatics with anatomical correlation. [ABSTRACT FROM AUTHOR]

Honey bees play a pivotal role in shaping ecosystems and sustaining human health as both pollinators and producers of health‐promoting products. However, honey bee colony mortality is on the rise globally, driven by various factors, including parasites, pesticides, habitat loss, poor nutrition, and climate change. This has far‐reaching consequences for the environment, economy, and human welfare. While efforts to address these issues are underway, the current progress in electron paramagnetic resonance (EPR) instrumentation affords using the immense potential of this magnetic resonance technique to study small samples such as honey bees. This paper presents the pioneering 2D in vivo EPR imaging experiment on a honey bee, revealing the ongoing redox‐status of bees' intestines. This way, by monitoring the spatio‐temporal changes of the redox‐active spin‐probes' EPR signal, it is possible to gain access to valuable information on the course of ongoing bees' pathologies and the prospect of following‐up on the efficiency of applied therapies. Employing a selection of diverse spin‐probes could further reveal pH levels and oxygen concentrations in bee tissues, allowing a noninvasive assessment of bee physiology. This approach offers promising strategies for safeguarding pollinators and understanding their biology, fostering their well‐being and ecological harmony. Research Highlights: Honey bees face rising mortality from parasites, pesticides, and climate change. This paper introduces original use of in vivo electron paramagnetic resonance imaging (EPRI) method to explore redox processes in honey bee intestines, advancing our understanding of these vital insects' health. [ABSTRACT FROM AUTHOR]

Musculoskeletal infections consist of different clinical conditions that are commonly encountered in daily clinical settings. As clinical findings and even laboratory tests cannot always be specific, imaging plays a crucial role in the diagnosis and treatment of these cases. Musculoskeletal infections most commonly occur secondary to direct inoculation into the skin involuntarily affected by trauma, microorganism, foreign bodies, or in diabetic ulcers; direct infections can also occur from voluntary causes due to surgery, vaccinations, or other iatrogenic procedures. Hematogenous spread of infection from a remote focus can also be a cause for musculoskeletal infections. Risk factors for soft tissue and bone infections include immunosuppression, old age, corticosteroid use, systemic illnesses, malnutrition, obesity, and burns. Most literature discusses musculoskeletal infections according to the diagnostic tools or forms of infection seen in different soft tissue anatomical planes or bones. This review article aims to evaluate musculoskeletal infections that occur due to direct inoculation to the musculoskeletal tissues, by focusing on the traumatic mechanism with emphasis on the radiological findings. [ABSTRACT FROM AUTHOR]

Magnetic resonance elastography (MRE) is a rapidly developing medical imaging technique that allows for quantitative assessment of the biomechanical properties of the tissue. MRE is now regarded as the most accurate noninvasive test for detecting and staging liver fibrosis. A two-dimensional (2D MRE) acquisition version is currently deployed at >2000 locations worldwide. 2D MRE allows for the evaluation of the magnitude of the complex shear modulus, also referred to as stiffness. The development of 3D vector MRE has enabled researchers to assess the biomechanical properties of small organs where wave propagation cannot be adequately analyzed with the 2D MRE imaging approach used in the liver. In 3D vector MRE, the shear waves are imaged and processed throughout a 3D volume and processed with an algorithm that accounts for wave propagation in any direction. Additionally, the motion is also imaged in x, y, and z directions at each voxel, allowing for more advanced processing to be applied. This review describes the technical principles of 3D vector MRE, surveys its clinical applications in small organs, and discusses potential clinical significance of 3D vector MRE. 3D vector MRE is a promising tool for characterizing the biomechanical properties of small organs such as the uterus, pancreas, thyroid, prostate, and salivary glands. However, its potential has not yet been fully explored. [Display omitted] • 3D Vector MRE has high clinical potential for the assessment of small organs. • 3D Vector MRE of the uterus, pancreas, thyroid, prostate, and parotid is feasible. • 3D Vector MRE provides information on the biomechanical properties of small organs. • 3D Vector MRE helps to differentiate between healthy and pathological tissue. • More research is needed to optimize the performance of 3D Vector MRE in small organs. [ABSTRACT FROM AUTHOR]

In this work, we explore the possibility of the n – n ¯ oscillation accompanied by CP-violation in the presence of magnetic fields. The n – n ¯ oscillation, which violates the baryon number ( B ) by two units ( ∣ Δ B ∣ = 2 ), can originate from the mixing between the neutron (n) and the neutral elementary particle (η) and may give rise to non-trivial physical consequences that can be testable in future experiments. We show that the probability of the n – n ¯ oscillation can be greatly enhanced by properly adjusting the magnetic field. In particular, the peak values of the oscillation probability in the presence of resonance magnetic fields can be 8–10 orders of magnitude higher than that in the absence of magnetic fields. We point out that there might not be sizable CP-violating effects in the n – n ¯ oscillation unless the mass of η is close to the mass of the neutron. We also analyze the interplay among various parameters associated with both B -violation and CP-violation and attempt to disentangle the effects of such parameters. The n – n ¯ oscillation process accompanied by CP-violation may open a promising avenue for exploring new physics beyond the Standard Model (SM). [ABSTRACT FROM AUTHOR]

Background and Aims It is uncertain whether ulcerative colitis leads to accumulated bowel damage on cross-sectional image. We aimed to characterise bowel damage in patients with ulcerative colitis using magnetic resonance imaging [MRI], and to determine its relation with duration of disease and the impact on patients' quality of life. Methods In this prospective study, patients with ulcerative colitis [UC] in endoscopic remission underwent MRI without bowel cleansing, and completed quality-of-life questionnaires. Participants' magnetic resonance findings were analysed considering normal values and thresholds determined in controls with no history of inflammatory bowel disease [ n =40], and in patients with Crohn's disease with no history of colonic involvement [ n  = 12]. Subjects with UC were stratified according to disease duration [< 7 years vs 7‒14 years vs > 14 years]. Results We analysed 41 subjects with ulcerative colitis [20 women; Mayo endoscopic subscore 0 in 38 [92.7%] and 1 in three [7.3%]]. Paired segment-by-segment comparison of magnetic resonance findings in colonic segments documented as being affected by ulcerative colitis versus controls showed that patients with ulcerative colitis had decreased cross-sectional area [ p  ≤ 0.0034] and perimeter [ p  ≤ 0.0005] and increased wall thickness [ p  = 0.026] in all segments. Colon damage, defined as wall thickness ≥ 3 mm, was seen in 22 [53.7%] patients. Colon damage was not associated with disease duration or quality of life. Conclusions Morphological abnormalities in the colon were highly prevalent in patients with ulcerative colitis in the absence of inflammation. Structural bowel damage was not associated with disease duration or quality of life. [ABSTRACT FROM AUTHOR]

Objective: To identify cardiovascular ultrasound predictors for brain anomalies in fetuses with heart disease. Methods: A literature search was performed in the following databases: MEDLINE through OVID, EMBASE, Cochrane Registry Center for Controlled Trials (CENTRAL), and LILACS, from their inception until May 2023. Clinical studies, cross‐sectional studies, case–control studies, cohorts, and systematic reviews were included. Data extraction was performed, and the risk of bias was assessed using the QUADAS‐2 tool. Results: Among 2705 studies evaluated, after filtering information, 10 articles were selected that met the inclusion criteria. These studies noted the following outcomes: a decrease in fetal head circumference, changes in brain maturation measured in days, decreased depth of brain fissures, and a decrease in total brain volume. The studies show a statistically significant correlation with the presence of the following cardiovascular predictors: low or mixed oxygen content in the ascending aorta (p < 0.001), retrograde flow in the aortic arch (p < 0.001), lower z values of the MCA‐PI (p < 0.05), higher UA‐PI z values (p < 0.01), and lower CPR (p < 0.05). In addition, lower values of left ventricular flow (p < 0.01), ductus arteriosus (p < 0.0001), and combined cardiac output index (p < 0.01) were reported. Conclusions: This review describes the most relevant evidence correlating the effects of hemodynamic changes that lead to states of chronic hypoxia related to the aforementioned changes in the central nervous system. [ABSTRACT FROM AUTHOR]