Modeling Highly Buoyant Flows in the Castel Giorgio: Torre Alfina Deep Geothermal Reservoir

The Castel Giorgio-Torre Alfina (CG-TA, central Italy) is a geothermal reservoir whose fluids are hosted in a carbonate formation at temperatures ranging between 120°C and 210°C. Data from deep wells suggest the existence of convective flow. We present the 3D numerical model of the CG-TA to simulate the undisturbed natural geothermal field and investigate the impacts of the exploitation process. The open source finite-element code OpenGeoSys is applied to solve the coupled systems of partial differential equations. The commercial software FEFLOW® is also used as additional numerical constraint. Calculated pressure and temperature have been calibrated against data from geothermal wells. The flow field displays multicellular convective patterns that cover the entire geothermal reservoir. The resulting thermal plumes protrude vertically over 3 km at Darcy velocity of about  m/s. The analysis of the exploitation process demonstrated the sustainability of a geothermal doublet for the development of a 5 MW pilot plant. The buoyant circulation within the geothermal system allows the reservoir to sustain a 50-year production at a flow rate of 1050 t/h. The distance of 2 km, between the production and reinjection wells, is sufficient to prevent any thermal breakthrough within the estimated operational lifetime. OGS and FELFOW results are qualitatively very similar with differences in peak velocities and temperatures. The case study provides valuable guidelines for future exploitation of the CG-TA deep geothermal reservoir.

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The Ferroelectric Domain Structures Induced by Electron Beam Scanning in Lithium Niobate

Ferroelectric domain structure has been formed under the action of electron beam scanning in congruent lithium niobate single crystal covered by surface dielectric layer. The obtained types of the domain patterns have been considered as subsequent stages of domain structure evolution. The dependence on irradiated charge density of domain density, length, and period of domain rays and stripe domain width was used for characterization of the domain structure evolution. The threshold irradiated charge density necessary for the formation of solid stripe domain has been revealed. All obtained results have been discussed in terms of kinetic approach based on the analogy between domain structure evolution and first-order phase transition.

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Suprasellar Ganglioglioma: Expanding the Differential Diagnosis

This case study describes a young man with symptoms suggestive of the presence of a space-occupying lesion within the cranial cavity. Imaging studies confirmed a lesion in the suprasellar region and surgical intervention to remove the tumor yielded an unexpected diagnosis. Neuroimaging characteristics and histopathology including immunohistochemistry are described. Gangliogliomas are uncommon CNS neoplasms and are most commonly found in the temporal and frontal lobes of young, male adults. They are rarely seen in the suprasellar region and only a handful of cases have been reported to date. The differential diagnoses associated with these suprasellar region lesions can be dependent on the age of the patient and neuroimaging characteristics. The present report highlights the importance of histopathological examination and the need to consider a wide range of diagnostic entities in the differential diagnosis of lesions in this topographic distribution, including rarely encountered tumors such as gangliogliomas.

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Liver Transplant for Unusually Large Polycystic Liver Disease: Challenges and Pitfalls

Patients with polycystic liver disease are described in the literature as both recipient and donor for liver transplant. Due to well-preserved liver function, it is often difficult for these patients to receive an organ. Livers of these patients are often large and heavier than a normal organ. We describe two cases who had exceedingly large livers, weighing 14 and 19 kg. To the best of our knowledge and search, these are some of the heaviest explanted livers, and one of the patients incidentally received a liver from a donor with ADPKD. The aim of this report is to discuss the challenges and pitfalls of evaluating and listing, technical aspect of the transplant, possibility of transplanting a liver from a donor with a genetic cystic disease to a cystic disease recipient, and the related literature with some highlights on the facts from UNOS/OPTN data.

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A Very Rare Case: HPV-Negative Vulvar Cancer in an Adolescent

Carcinoma of the vulva is usually regarded as a disease of older women, with the typical age of 65–85 years. There are a limited number of reports of vulvar cancer cases younger than 30 years. These patients have usually risk factors such as human papillomavirus (HPV) infection and immunosuppression. Herein, we present a case of invasive squamous vulvar cancer in an 18-year-old patient without any risk factor. Vulvar radical local excision and bilateral inguinal sentinel lymph node biopsies were performed. The clitoris was preserved during the surgery. Patient did not receive adjuvant therapy. Follow-up after 12 months of the disease showed no evidence of disease. Vulvar carcinoma in very young women may develop without any predisposing factor. Early detection will result in better survival. So, there should be a high index of suspicion when a vulvar lesion is seen, even if the patient falls below the typical age range and does not carry any well-known risk factors such as HPV infection and immunodeficiency.

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Robust Semi-Supervised Manifold Learning Algorithm for Classification

In the recent years, manifold learning methods have been widely used in data classification to tackle the curse of dimensionality problem, since they can discover the potential intrinsic low-dimensional structures of the high-dimensional data. Given partially labeled data, the semi-supervised manifold learning algorithms are proposed to predict the labels of the unlabeled points, taking into account label information. However, these semi-supervised manifold learning algorithms are not robust against noisy points, especially when the labeled data contain noise. In this paper, we propose a framework for robust semi-supervised manifold learning (RSSML) to address this problem. The noisy levels of the labeled points are firstly predicted, and then a regularization term is constructed to reduce the impact of labeled points containing noise. A new robust semi-supervised optimization model is proposed by adding the regularization term to the traditional semi-supervised optimization model. Numerical experiments are given to show the improvement and efficiency of RSSML on noisy data sets.

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Comparison of Three Sample Preparation Procedures for the Quantification of L-Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma Using HPLC-FLD

Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were compared regarding the quantification of L-arginine and ADMA in human plasma: (A) protein precipitation (PP) based on aqueous trichloroacetic acid (TCA), (B) PP using a mixture of ammonia and acetonitrile, and (C) solid-phase extraction (SPE). The samples were analysed by using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The analytical performance of (A) was comparable with that of (C), demonstrating recoveries of >90%, coefficient of variations (CVs, %) of 0.994), precision (

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