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The chirality-induced spin selectivity (CISS) effect is a fascinating phenomenon that correlates the molecular structure with electron spin-polarization (SP). Experimental procedures to quantify the spin-filtering magnitude have extensively used magnetic-field-dependent conductive AFM. In this work chiral crystals of imide-substituted coronene bisimide ((S)-CBI-GCH) are studied to explain the dynamics of the current-voltage I - V spectra and the origin of superimposed peaks are investigated. A dynamic voltage-sweep rate-dependent phenomenon can give rise to complex I - V curves. The redox group, capable of localization of charge, acts as a localized state that interferes with the continuum of the π - π stacking, giving rise to Fano resonances. A novel mechanism for dynamic transport is introduced, which provides insight into the origin of spin-polarized charge in crystallized CBI-GCH molecules after absorption on a metallic substrate, guided by transient charge polarization. Crucially, interference between charge localization and delocalization during transport may be important properties in understanding the magnetochiral phenomena observed by electrostatic force microscopy. Finally, it is observed that charge trapping sensitively modifies the injection barrier from direct tunneling to Fowler-Nordheim tunneling transport supporting nonlinearity in CISS for this class of molecules.

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Multi-energy computed tomography (MECT) offers the opportunity for advanced visualization, detection, and quantification of select elements (e.g., iodine) or materials (e.g., fat) beyond the capability of standard single-energy computed tomography (CT). However, the use of MECT requires careful consideration as substantially different hardware and software approaches have been used by manufacturers, including different sets of user-selected or hidden parameters that affect the performance and radiation dose of MECT. Another important consideration when designing MECT protocols is appreciation of the specific tasks being performed; for instance, differentiating between two different materials or quantifying a specific element. For a given task, it is imperative to consider both the radiation dose and task-specific image quality requirements. Development of a quality control (QC) program is essential to ensure the accuracy and reproducibility of these MECT applications. Although standard QC procedures have been well established for conventional single-energy CT, the substantial differences between single-energy CT and MECT in terms of system implementations, imaging protocols, and clinical tasks warrant QC tests specific to MECT. This task group was therefore charged with developing a systematic QC program designed to meet the needs of MECT applications. In this report, we review the various MECT approaches that are commercially available, including information about hardware implementation, MECT image types, image reconstruction, and postprocessing techniques that are unique to MECT. We address the requirements for MECT phantoms, review representative commercial MECT phantoms, and offer guidance regarding homemade MECT phantoms. We discuss the development of MECT protocols, which must be designed carefully with proper consideration of MECT technology, imaging task, and radiation dose. We then outline specific recommended QC tests in terms of general image quality, radiation dose, differentiation and quantification tasks, and diagnostic and therapeutic applications.

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BACKGROUND: Epidemiological research on fractures in children under the age of two is of great importance to help understand differences between accidental and abusive trauma. OBJECTIVE: This systematic review aimed to evaluate studies reporting on the incidence of fractures in children under two years of age, excluding birth injuries. Secondary outcome measures included fracture location, mechanisms of injury and fracture characteristics. METHODS: A systematic literature review (1946 to February 7th 2024), including prospective and retrospective cohort studies and cross-sectional cohort studies, was performed. Studies including children from other age groups were included if the actual measures for those aged 0-2 years could be extracted. We also included studies restricted to infants. Annual incidence rates of fractures were extracted and reported as the main result. Critical appraisal of was performed using the Appraisal tool for Cross-Sectional Studies. RESULTS: Twelve moderate to good quality studies met eligibility criteria, of which seven were based on data from medical records and five were registry studies. Studies investigated different aspects of fractures, making comprehensive synthesis challenging. There was an overall annual fracture incidence rate of 5.3 to 9.5 per 1,000 children from 0-2 years of age; with commonest sites being the radius/ulna (25.2-40.0%), followed by tibia/fibula (17.3-27.6%) and the clavicle (14.6-14.8%) (location based on 3 studies with a total of 407 patients). In infants, the reported incidence ranged between 0.7 to 4.6 per 1,000 (based on 3 studies), with involvement of the clavicle in 22.2% and the distal humerus in 22.2% of cases (based on 1 study). Only a single metaphyseal lesion was reported (proximal humerus of an 11-month-old infant). Fracture mechanisms were detailed in four studies, with fall from chair, bed, table, own height or fall following indoor activities causing 50-60% of fractures. CONCLUSIONS: There is a paucity of good quality data on fracture incidence in children under the age of two. Larger, prospective and unbiased studies would be helpful in determining normal pattern of injuries, so that differences from abusive trauma may be better understood.

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BACKGROUND: Many transition-to-practice programs have been developed to support novice nurses during their first years into practice. These programs report improvements in retention, wellbeing and clinical competence, but the driving mechanisms of these interventions remain largely unclear. OBJECTIVE: To identify how transition-to-practice programs for novice nurses work and in what contexts they work successfully. METHODS: A realist review was conducted. Eligibility criteria included intervention studies aimed at novice nurses in their first two years of practice that reported outcomes on organizational or individual nurse level. The underlying theory of included transition-to-practice programs was extracted, and relevant contextual factors, mechanisms and outcomes were explored and synthesized into context-mechanism-outcome (CMO) configurations. The search was limited to studies between 2000 and 2023. RESULTS: A total of 32 studies were included, evaluating 30 different transition-to-practice programs with a wide range of intervention components including stress management, clinical education, professional and peer support, and ward rotations. Transition-to-practice programs were often designed without a theoretical foundation. Driving mechanisms behind the programs pertained to psychological, professional, and social development. Contextual factors that activated the mechanisms were enabling conditions for mentors and novice nurses, selection and motivation of novice nurses and organizational culture. CONCLUSIONS: Current transition-to-practice programs primarily focus on the individual and professional development of nurses. However, transition to practice can benefit from a systemic approach that includes development initiatives on the organizational level. REGISTRATION: PROSPERO ID CRD42021268080, August 15, 2021. TWEETABLE ABSTRACT: Context and mechanisms determine successful implementation of transition to practice programs for novice nurses. @transitiontopractice @nurseworkforce.

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Synthetic micro/nanomotors have been extensively exploited over the past decade to achieve active transportation. This interest is a result of their broad range of potential applications, from environmental remediation to nanomedicine. Nevertheless, it still remains a challenge to build a fast-moving biodegradable polymeric nanomotor. Here we present a light-propelled nanomotor by introducing gold nanoparticles (Au NP) onto biodegradable bowl-shaped polymersomes (stomatocytes) via electrostatic and hydrogen bond interactions. These biodegradable nanomotors show controllable motion and remarkable velocities of up to 125 µm s-1. This unique behavior is explained via a thorough three-dimensional characterization of the nanomotor, particularly the size and the spatial distribution of Au NP, with cryogenic transmission electron microscopy (cryo-TEM) and cryo-electron tomography (cryo-ET). Our in-depth quantitative 3D analysis reveals that the motile features of these nanomotors are caused by the nonuniform distribution of Au NPs on the outer surface of the stomatocyte along the z-axial direction. Their excellent motile features are exploited for active cargo delivery into living cells. This study provides a new approach to develop robust, biodegradable soft nanomotors with application potential in biomedicine.

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The Frontline and Relapsed Rhabdomyosarcoma (FaR-RMS) clinical trial is an overarching, multinational study for children and adults with rhabdomyosarcoma (RMS). The trial, developed by the European Soft Tissue Sarcoma Study Group (EpSSG), incorporates multiple different research questions within a multistage design with a focus on (i) novel regimens for poor prognostic subgroups, (ii) optimal duration of maintenance chemotherapy, and (iii) optimal use of radiotherapy for local control and widespread metastatic disease. Additional sub-studies focusing on biological risk stratification, use of imaging modalities, including [18F]FDG PET-CT and diffusion-weighted MRI imaging (DWI) as prognostic markers, and impact of therapy on quality of life are described. This paper forms part of a Special Issue on rhabdomyosarcoma and outlines the study background, rationale for randomisations and sub-studies, design, and plans for utilisation and dissemination of results.

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Inflicted shaking trauma can cause injury in infants, but exact injury mechanisms remain unclear. Controversy exists, particularly in courts, whether additional causes such as impact are required to produce injuries found in cases of (suspected) shaking. Publication rates of studies on animal and biomechanical models of inflicted head injury by shaking trauma (IHI-ST) in infants continue rising. Dissention on the topic, combined with its legal relevance, makes maintaining an up-to-date, clear and accessible overview of the current knowledge-base on IHI-ST essential. The current work reviews recent (2017-2023) studies using models of IHI-ST, serving as an update to two previously published reviews. A systematic review was conducted in Scopus and PubMed for articles using animal, physical and mathematical models for IHI-ST. Using the PRISMA methodology, two researchers independently screened the publications. Two, five, and ten publications were included on animal, physical, and mathematical models of IHI-ST, respectively. Both animal model studies used rodents. It is unknown to what degree these can accurately represent IHI-ST. Physical models were used mostly to investigate gross head-kinematics during shaking. Most mathematical models were used to study local effects on the eye and the head's internal structures. All injury thresholds and material properties used were based on scaled adult or animal data. Shaking motions used as inputs for animal, physical and mathematical models were mostly greatly simplified. Future research should focus on using more accurate shaking inputs for models, and on developing or and validating accurate injury thresholds applicable for shaking.

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PURPOSE: To improve radiopacity of radiolucent absorbable poly-p-dioxanone (PPDO) inferior vena cava filters (IVCFs) and demostrate their effectiveness in clot-trapping ability. MATERIALS AND METHODS: Tungsten nanoparticles (WNPs) were incorporated along with polyhydroxybutyrate (PHB), polycaprolactone (PCL), and polyvinylpyrrolidone (PVP) polymers to increase the surface adsorption of WNPs. The physicochemical and in vitro and in vivo imaging properties of PPDO IVCFs with WNPs with single-polymer PHB (W-P) were compared with those of WNPs with polymer blends consisting of PHB, PCL, and PVP (W-PB). RESULTS: In vitro analyses using PPDO sutures showed enhanced radiopacity with either W-P or W-PB coating, without compromising the inherent physicomechanical properties of the PPDO sutures. W-P- and W-PB-coated IVCFs were deployed successfully into the inferior vena cava of pig models with monitoring by fluoroscopy. At the time of deployment, W-PB-coated IVCFs showed a 2-fold increase in radiopacity compared to W-P-coated IVCFs. Longitudinal monitoring of in vivo IVCFs over a 12-week period showed a drastic decrease in radiopacity at Week 3 for both filters. CONCLUSIONS: The results highlight the utility of nanoparticles (NPs) and polymers for enhancing radiopacity of medical devices. Different methods of incorporating NPs and polymers can still be explored to improve the effectiveness, safety, and quality of absorbable IVCFs.

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BACKGROUND: Distinguishing congenital pulmonary airway malformations (CPAMs) from pleuropulmonary blastoma (PPB) can be challenging. Previously diagnosed patients with CPAM may have been misdiagnosed and we may have missed DICER1-associated PPBs, a diagnosis with important clinical implications for patients and their families. To gain insight in potential misdiagnoses, we systematically assessed somatic DICER1 gene mutation status in an unselected, retrospective cohort of patients with a CPAM diagnosis. METHODS: In the Amsterdam University Medical Center (the Netherlands), it has been standard policy to resect CPAM lesions. We included all consecutive cases of children (age 0-18 years) with a diagnosis of CPAM between 2007 and 2017 at this center. Clinical and radiographic features were reviewed, and DICER1 gene sequencing was performed on DNA retrieved from CPAM tissue samples. RESULTS: Twenty-eight patients with a surgically removed CPAM were included. CPAM type 1 and type 2 were the most common subtypes (n = 12 and n = 13). For 21 patients a chest CT scan was available for reassessment by two pediatric radiologists. In 9 patients (9/21, 43%) the CPAM subtype scored by the radiologists did not correspond with the subtype given at pathology assessment. No pathogenic mutations and no copy number variations of the DICER1 gene were found in the DNA extracted from CPAM tissue (0/28). CONCLUSIONS: Our findings suggest that the initial CPAM diagnoses were correct. These findings should be validated through larger studies to draw conclusions regarding whether systematic DICER1 genetic testing is required in children with a pathological confirmed diagnosis of CPAM or not. LEVEL OF EVIDENCE: Level IV.

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OBJECTIVE: To investigate the feasibility of diffusion-weighted magnetic resonance imaging (DW-MRI) as a predictive imaging marker after neoadjuvant chemotherapy in patients with rhabdomyosarcoma. MATERIAL AND METHODS: We performed a multicenter retrospective study including pediatric, adolescent and young adult patients with rhabdomyosarcoma, Intergroup Rhabdomyosarcoma Study group III/IV, treated according to the European paediatric Soft tissue sarcoma Study Group (EpSSG) RMS2005 or MTS2008 studies. DW-MRI was performed according to institutional protocols. We performed two-dimensional single-slice tumor delineation. Areas of necrosis or hemorrhage were delineated to be excluded in the primary analysis. Mean, median and 5th and 95th apparent diffusion coefficient (ADC) were extracted. RESULTS: Of 134 included patients, 82 had measurable tumor at diagnosis and response and DW-MRI scans of adequate quality and were included in the analysis. Technical heterogeneity in scan acquisition protocols and scanners was observed. Mean ADC at diagnosis was 1.1 (95% confidence interval [CI]: 1.1-1.2) (all ADC expressed in * 10-3 mm2/s), versus 1.6 (1.5-1.6) at response assessment. The 5th percentile ADC was 0.8 (0.7-0.9) at diagnosis and 1.1 (1.0-1.2) at response. Absolute change in mean ADC after neoadjuvant chemotherapy was 0.4 (0.3-0.5). Exploratory analyses for association between ADC and clinical parameters showed a significant difference in mean ADC at diagnosis for alveolar versus embryonal histology. Landmark analysis at nine weeks after the date of diagnosis showed no significant association (hazard ratio 1.3 [0.6-3.2]) between the mean ADC change and event-free survival. CONCLUSION: A significant change in the 5th percentile and the mean ADC after chemotherapy was observed. Strong heterogeneity was identified in DW-MRI acquisition protocols between centers and in individual patients.

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Rhabdomyosarcoma is the most common soft-tissue neoplasm in the pediatric population. The survival of children with rhabdomyosarcoma has only marginally improved over the past 25 years and remains poor for those with metastatic disease. A significant challenge to advances in treatment of rhabdomyosarcoma is the relative rarity of this disease, necessitating years to complete clinical trials. Progress can be accelerated by international cooperation and sharing national experiences. This necessitates agreement on a common language to describe patient cohorts and consensus standards to guide diagnosis, treatment, and response assessment. These goals formed the premise for creating the INternational Soft Tissue saRcoma ConsorTium (INSTRuCT) in 2017. Multidisciplinary members of this consortium have since developed international consensus statements on the diagnosis, treatment, and management of pediatric soft-tissue sarcomas. Herein, members of the INSTRuCT Diagnostic Imaging Working Group present international consensus recommendations for imaging of patients with rhabdomyosarcoma at diagnosis, at staging, and during and after completion of therapy. The intent is to promote a standardized imaging approach to pediatric patients with this malignancy to create more-reliable comparisons of results of clinical trials internationally, thereby accelerating progress in managing rhabdomyosarcoma and improving survival.

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BACKGROUND: Thermochemical ablation (TCA) is a minimally invasive therapy under development for hepatocellular carcinoma. TCA simultaneously delivers an acid (acetic acid, AcOH) and base (sodium hydroxide, NaOH) directly into the tumor, where the acid/base chemical reaction produces an exotherm that induces local ablation. However, AcOH and NaOH are not radiopaque, making monitoring TCA delivery difficult. PURPOSE: We address the issue of image guidance for TCA by utilizing cesium hydroxide (CsOH) as a novel theranostic component of TCA that is detectable and quantifiable with dual-energy CT (DECT). MATERIALS AND METHODS: To quantify the minimum concentration of CsOH that can be positively identified by DECT, the limit of detection (LOD) was established in an elliptical phantom (Multi-Energy CT Quality Assurance Phantom, Kyoto Kagaku, Kyoto, Japan) with two DECT technologies: a dual-source system (SOMATOM Force, Siemens Healthineers, Forchheim, Germany) and a split-filter, single-source system (SOMATOM Edge, Siemens Healthineers). The dual-energy ratio (DER) and LOD of CsOH were determined for each system. Cesium concentration quantification accuracy was evaluated in a gelatin phantom before quantitative mapping was performed in ex vivo models. RESULTS: On the dual-source system, the DER and LOD were 2.94 and 1.36-mM CsOH, respectively. For the split-filter system, the DER and LOD were 1.41- and 6.11-mM CsOH, respectively. The signal on cesium maps in phantoms tracked linearly with concentration (R2  = 0.99) on both systems with an RMSE of 2.56 and 6.72 on the dual-source and split-filter system, respectively. In ex vivo models, CsOH was detected following delivery of TCA at all concentrations. CONCLUSIONS: DECT can be used to detect and quantify the concentration of cesium in phantom and ex vivo tissue models. When incorporated in TCA, CsOH performs as a theranostic agent for quantitative DECT image-guidance.

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BACKGROUND: Limited data exist on the clinical behavior of pediatric non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) with distant metastases at onset, and a clear standard of care has not yet been defined. METHODS: This cohort study reports on pediatric adult-type metastatic NRSTS enrolled in two concurrent prospective European studies, i.e., the randomized BERNIE study and the single-arm MTS 2008 study developed by the European paediatric Soft tissue sarcoma Study Group. Treatment programs were originally designed for patients with metastatic rhabdomyosarcoma, i.e., nine courses of multidrug chemotherapy (with or without bevacizumab in the BERNIE study), followed by 12 cycles of maintenance therapy, whereas radiotherapy and/or surgery (on primary tumor and/or metastases) were delayed until after seven courses of chemotherapy had been administered. RESULTS: The study included 61 patients <21 years old treated from July 2008 to December 2016. The lung was the site of metastases in 75% of the cases. All patients received multi-agent chemotherapy, 44% had local therapy to primary tumor, and 18% had treatment of metastases. Median time to progression/relapse was 6 months. A high rate of tumor progression was observed during the initial part of the chemotherapy program. With a median follow-up of 41.5 months (range, 2-111 months), 3-year event-free survival and overall survival were 15.4% (95% confidence interval [CI], 7.6-25.7) and 34.9% (95% CI, 22.7-47.5), respectively. There were no statistically significant differences in outcome depending on the type of treatment administered. CONCLUSIONS: The study confirmed the overall poor outcome for patients with metastatic NRSTS, whose treatment remains a challenge. PLAIN LANGUAGE SUMMARY: Pediatric non-rhabdomyosarcoma soft tissue sarcomas form a heterogeneous group of rare tumors. Although recent international studies have defined the standard of care for patients with localized disease, limited data are available on the clinical behavior of patients with distant metastases. This study on 61 metastatic cases treated on two prospective European protocols confirms that the chances of survival of such patients are often dismal and a standard treatment is still lacking.

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This second roundtable discussion was convened at the 56th European Society of Paediatric Radiology (ESPR) 2022 Annual Meeting in Marseille, France, to discuss controversial aspects of imaging in child abuse. The following topics were discussed: Fracture dating-the published literature is broadly similar with respect to the identification of the radiographic stages of bony healing. The non-expert/general radiologist is encouraged to use broad descriptors of fracture healing (acute, healing or old) within their reports, rather than attempting to date fractures. The more experienced/expert radiologist, who may provide a timeframe/range to assist the courts, should be aware that any published timeframes are not absolute and that recent research indicates that the rate of healing may differ according to the bone affected and the age of the patient. Whole spine imaging in suspected abusive head trauma-this is recommended to enable a complete assessment of the neuraxis when abusive head trauma is suspected or diagnosed, particularly in the presence of intracranial and cervical subdural haemorrhage and cervical ligamentous injury. Cranial imaging in suspected physical abuse-both computed tomography (CT) and magnetic resonance imaging (MRI) remain complimentary depending on the clinical context in which they are used with CT remaining first-line in the assessment of children with (suspected abusive) head trauma prior to an early MRI. MRI is superior in its assessment of parenchymal injury and may be employed as first-line in age appropriate asymptomatic siblings of a child with suspected physical abuse.

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In infants without a history of trauma, subdural haemorrhages should raise the concern for an abusive head injury, particularly when they are associated with bridging vein clotting/rupture or with septations. However, non-haemorrhagic, fluid-appearing subdural collections (also called hygromas) may also be the result of abuse. Subdural collections have also been uncommonly observed in patients with benign enlargement of the subarachnoid spaces (BESS) and a few large-scale studies accurately investigate the incidence and the significance. Currently, there is a wide variation of practices in children with BESS and subdural collections. Due to the social risks associated with abuse evaluation and the perceived risk of radiation exposure, there might be a reluctance to fully evaluate these children in some centres. The diagnosis of physical abuse cannot be substantiated nor safely excluded in infants with BESS and subdural collection(s), without investigation for concomitant traumatic findings. The exact prevalence of occult injuries and abuse in these infants is unknown. In macrocephalic infants with subdural collections and imaging features of BESS, thorough investigations for abuse are warranted and paediatricians should consider performing full skeletal surveys even when fundoscopy, social work consult, and detailed clinical evaluation are unremarkable.

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Importance: Physical abuse is a common but preventable cause of long-term childhood morbidity and mortality. Despite the strong association between abuse in an index child and abuse in contact children, there is no guidance outlining how to screen the latter, significantly more vulnerable group, for abusive injuries. Consequently, the radiological assessment of contact children is often omitted, or variably performed, allowing occult injuries to go undetected and increasing the risk of further abuse. Objective: To report an evidence-based and consensus-derived set of best practices for the radiological screening of contact children in the context of suspected child physical abuse. Evidence Review: This consensus statement is supported by a systematic review of the literature and the clinical opinion of an internationally recognized group of 26 experts. The modified Delphi consensus process comprised 3 meetings of the International Consensus Group on Contact Screening in Suspected Child Physical Abuse held between February and June 2021. Findings: Contacts are defined as the asymptomatic siblings, cohabiting children, or children under the same care as an index child with suspected child physical abuse. All contact children should undergo a thorough physical examination and a history elicited prior to imaging. Contact children younger than 12 months should have neuroimaging, the preferred modality for which is magnetic resonance imaging, and skeletal survey. Contact children aged 12 to 24 months should undergo skeletal survey. No routine imaging is indicated in asymptomatic children older than 24 months. Follow-up skeletal survey with limited views should be performed if abnormal or equivocal at presentation. Contacts with positive findings should be investigated as an index child. Conclusions and Relevance: This Special Communication reports consensus recommendations for the radiological screening of contact children in the context of suspected child physical abuse, establishing a recognized baseline for the stringent evaluation of these at-risk children and providing clinicians with a more resilient platform from which to advocate for them.

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Rhabdomyosarcoma, although rare, is the most frequent soft tissue sarcoma in children and adolescents. It can present as a mass at nearly any site in the body, with most common presentations in the head and neck, genitourinary tract and extremities. The optimal diagnostic approach and management of rhabdomyosarcoma require a multidisciplinary team with multimodal treatment, including chemotherapy and local therapy. Survival has improved over the last decades; however, further improvement in management is essential with current 5-year overall survival ranging from 35% to 100%, depending on disease and patient characteristics. In the full patient journey, from diagnosis, staging, management to follow-up after therapy, the paediatric radiologist and nuclear physician are essential members of the multidisciplinary team. Recently, guidelines of the European paediatric Soft tissue sarcoma Study Group, the Cooperative Weichteilsarkom Studiengruppe and the Oncology Task Force of the European Society of Paediatric Radiology (ESPR), in an ongoing collaboration with the International Soft-Tissue Sarcoma Database Consortium, provided guidance for high-quality imaging. In this educational paper, given as a lecture during the 2022 postgraduate ESPR course, the multi-disciplinary team of our national paediatric oncology centre presents the journey of two patients with rhabdomyosarcoma and discusses the impact on and considerations for the clinical (paediatric) radiologist and nuclear physician. The key learning points of the guidelines and their implementation in clinical practice are highlighted and up-to-date insights provided for all aspects from clinical suspicion of rhabdomyosarcoma and its differential diagnosis, to biopsy, staging, risk stratification, treatment response assessment and follow-up.

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