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The relationship between solar magnetic activity and solar wind parameters, with observed time-delayed mutual coupling, is an outstanding challenge in space physics. In this study, drawing inspiration from recent observations, we propose a reconciliation framework whose fundamentals stand in the Parker model for solar wind expansion. We investigate the effects on fluctuations in solar wind speed when linearly sustained by an oscillating magnetic solar dynamo described via a modified Van der Pol nonlinear oscillator mimicking the magnetic activity at different timescales. Our findings reveal the presence of a "space-climatic feedback" that, in absence of the driving magnetic activity, slows down solar wind velocity fluctuations. The combined action of the slowing down of fluctuations and a periodic driving is the responsible for the time-delay between solar magnetic activity and solar wind dynamics. Furthermore, we also demonstrate how the space-climatic feedback controls the value of the time-delay which depends on the different periodicities of the driving magnetic activity. This holistic approach provides a formal link at the interplay between solar magnetic activity and solar wind dynamics through the interplanetary space which can advance our understanding of long-term effects of solar activity on solar wind variations, and consequently on interactions with planetary environments.

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PURPOSE: This study's main objective is to assess the feasibility of processing the MRI information with identified ACL-footprints into 2D-images similar to a conventional anteroposterior and lateral X-Ray image of the knee. The secondary aim is to conduct specific measurements to assess the reliability and reproducibility. This study is a proof of concept of this technique. METHODS: Five anonymised MRIs of a right knee were analysed. A orthopaedic knee surgeon performed the footprints identification. An ad-hoc software allowed a volumetric 3D image projection on a 2D anteroposterior and lateral view. The previously defined anatomical femoral and tibial footprints were precisely identified on these views. Several parameters were measured (e.g. coronal and sagittal ratio of tibial footprint, sagittal ratio of femoral footprint, femoral intercondylar notch roof angle, proximal tibial slope and others). The intraclass correlation coefficient (ICCs), including 95% confidence intervals (CIs), has been calculated to assess intraobserver reproducibility and interobserver reliability. RESULTS: Five MRI scans of a right knee have been assessed (three females, two males, mean age of 30.8 years old). Five 2D-"CLASS" have been created. The measured parameters showed a "substantial" to "almost perfect" reproducibility and an "almost perfect" reliability. CONCLUSION: This study confirmed the possibility of generating "CLASS" with the localised centroid of the femoral and tibial ACL footprints from a 3D volumetric model. "CLASS" also showed that these footprints were easily identified on standard anteroposterior and lateral X-Ray views of the same patient, thus allowing an individual identification of the anatomical femoral and tibial ACL's footprints. LEVEL OF EVIDENCE: Level IV diagnostic study.

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The turbulent thermal convection on the Sun is an example of an irreversible non-equilibrium phenomenon in a quasi-steady state characterized by a continuous entropy production rate. Here, the statistical features of a proxy of the local entropy production rate, in solar quiet regions at different timescales, are investigated and compared with the symmetry conjecture of the steady-state fluctuation theorem by Gallavotti and Cohen. Our results show that solar turbulent convection satisfies the symmetries predicted by the fluctuation relation of the Gallavotti and Cohen theorem at a local level.

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The aim of this paper is to describe the usefulness of multiparametric US in the diagnosis and subsequent follow-up of a case of right-side ischemic colitis and to present a review of the data reported in the literature. Ischemic colitis is frequently diagnosed in the field of gastroenterology. Diagnosis is usually based on the outcome of endoscopy and histological examination, and in case of right-side ischemic colitis also on the results of contrast-enhanced CT. In the described case, multiparametric US indicated the diagnosis including a prognostic judgment, and during follow-up US-monitored patency of the stents positioned under angiographic guidance. One of the available US techniques, CEUS, seems to have a special role in the detection of residual vascularization of the gastrointestinal tract affected by ischemia. However, before introducing this method into daily clinical practice, further studies are required to confirm its diagnostic accuracy.

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Strain elastography is a recently developed ultrasound method that seems to contribute to the diagnosis and monitoring of inflammatory bowel diseases. This pictorial essay aims to present the feasibility of strain elastography in clinical practice by comparing visual observation and semiquantitative parameters with endoscopic or radiological images in some common cases of Crohn's disease. In our opinion, strain elastography with visual observation is easily performed in connection with B-mode ultrasound and color Doppler imaging and may provide relevant information. Strain elastography with the elaboration of semiquantitative parameters is not as immediate as the visual observation method, but it seems to provide more objective data and seems more appropriate for monitoring the evolution of the disease. However, for the elastographic method to extensively contribute in inflammatory bowel diseases, standardization and further studies are required to confirm the promising results already reported in the literature.

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We report a new case of benign solitary fibrous tumor (SFT) of the liver. A 65-year-old man presented to our unit with upper right abdominal discomfort. On examination abdominal distension was present and palpation showed a large firm mass in the right hypochondrium and epigastrium. The patient's past medical history was not significant and laboratory tests were normal. Ultrasonography and computed tomography showed a large tumor, 20 cm in diameter, in the right lobe of the liver. An extended right hepatectomy was performed. The tumor measured 30 x 28 x 14 cm and weighed 4725 g. Microscopic evaluation showed a benign SFT of the liver with tumor cells typically positive for vimentin and CD34. The postoperative course was uneventful, and the patient is alive 30 months after surgery. This is a rare neoplasm of mesenchymal origin that occasionally involves the liver in adult patients. Most SFTs are benign, but some may have malignant histological features and recur locally or metastasize. Because of their rarity, overall experience has not been significant and little has been published concerning this tumor, Including the present one, 28 cases have been reported in the English literature. Surgery is the mainstay of treatment. Little can be said about the benefits of adjuvant radiochemotherapy in these patients. As SFT of the liver is often a benign neoplasm, chemotherapy or radiotherapy should not be necessary, and should be reserved for when resection is incomplete and/or histological examination reveals features of malignancy. Surgeons must be aware of SFT of the liver, and this neoplasm should be included in the differential diagnosis of a single large hepatic mass.

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The authors report the case of a malignant haemangiopericytoma found in an uncommon location, namely the mesorectum. Haemangiopericytomas of the mesorectum are rare mesenchymal tumours of vascular origin that usually occur in the musculature of the extremities, retroperitoneum, pelvis (uterus, ovary and urinary bladder), head, neck and lungs. Rare sites include the liver, pancreas, stomach and greater omentum. Because of their rarity the overall experience has not been significant and little has been published concerning such tumours. In addition, the difficult interpretation of the histological evidence and the poor prognosis of the disease may still give rise to problems in terms of clinical management. Haemangiopericytomas of the retrorectal space, however, seem to behave like malignant tumours: the clinical course is poor and survival short, despite radical surgery, due to early distant metastases and local recurrence. Surgery still remains the mainstay of treatment. Adjuvant therapies should be considered.

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