Polynomial approximation of derivatives by the constrained mock-Chebyshev least squares operator

The constrained mock-Chebyshev least squares operator is a linear approximation operator based on an equispaced grid of points. Like other polynomial or rational approximation methods, it was recently introduced in order to defeat the Runge phenomenon that occurs when using polynomial interpolation on large sets of equally spaced points. The idea is to improve the mock-Chebyshev subset interpolation, where the considered function $f$ is interpolated only on a proper subset of the uniform grid, formed by nodes that mimic the behavior of Chebyshev--Lobatto nodes. In the mock-Chebyshev subset interpolation all remaining nodes are discarded, while in the constrained mock-Chebyshev least squares interpolation they are used in a simultaneous regression, with the aim to further improving the accuracy of the approximation provided by the mock-Chebyshev subset interpolation. The goal of this paper is two-fold. We discuss some theoretical aspects of the constrained mock-Chebyshev least squares operator and present new results. In particular, we introduce explicit representations of the error and its derivatives. Moreover, for a sufficiently smooth function $f$ in $[-1,1]$, we present a method for approximating the successive derivatives of $f$ at a point $x\in [-1,1]$, based on the constrained mock-Chebyshev least squares operator and provide estimates for these approximations. Numerical tests demonstrate the effectiveness of the proposed method.Comment: 17 pages, 23 figure

Renal papillary carcinoma developed in a kidney transplant recipient with late IgA-nephropathy

With improvements in immunosuppressive therapy, patient and graft survival in renal transplant recipients have been prolonged. Increasing donor age and patient survival rates have been related to an increase in the number of de novo tumors. Posttransplant malignancy in these patients is an important cause of graft loss and death in these patients. Among cancers occurring after a kidney transplant, renal cell carcinoma is the fifth most common malignancy after lymphoproliferative disorders, and skin, gastrointestinal, and lung cancers. When nonmelanoma skin cancers and in situ carcinoma of the cervix are excluded from malignancies, renal cell carcinoma accounts for 2% of all cancers in the general population, which increases to 5% in solid-organ recipients. The majority of renal cell carcinomas found in transplant recipients develop in the recipient 's native kidneys, but only 9% of tumors develop in the allograft itself. Tumors transmitted by donors represent only 0.02% to 0.2% of cases. Most de novo allograft renal cell carcinomas are single tumors. The mechanisms of development of renal cell carcinoma in renal grafts are not completely understood

Experimental investigation on cyclic response of RC elements repaired by CFRP external reinforcing systems

This paper deals with the experimental results of an investigation aimed at studying cyclic response of half scaled RC specimens previously damaged and then repaired with externally bonded carbon fiber reinforced polymer sheets. The research involved the test of ten specimens. Two of them were tested without any external strengthening material in order to provide a reference for the response of repaired specimens. These latter were tested after a previous damaging procedure and a subsequent repair intervention with fiber reinforced polymer composites. The parameters under investigation were the level of initial damage, the strengthening configuration, and the level of axial load. Test results have pointed out effectiveness of the adopted strengthening systems, since repaired specimens exhibited better mechanical responses than the unstrengthened ones

Spermatogonial kinetics in humans

The human spermatogonial compartment is essential for daily production of millions of sperm. Despite this crucial role, the molecular signature, kinetic behavior and regulation of human spermatogonia are poorly understood. Using human testis biopsies with normal spermatogenesis and by studying marker protein expression, we have identified for the first time different subpopulations of spermatogonia. MAGE-A4marks all spermatogonia, KITmarks all Bspermatogonia and UCLH1 all Apale-dark (Ap-d) spermatogonia. We suggest that at the start of the spermatogenic lineage there are Ap-d spermatogonia that are GFRA1High, likely including the spermatogonial stem cells. Next, UTF1 becomes expressed, cells become quiescent and GFRA1 expression decreases. Finally, GFRA1 expression is lost and subsequently cells differentiate into B spermatogonia, losing UTF1 and acquiring KIT expression. Strikingly, most human Ap-d spermatogonia are out of the cell cycle and even differentiating type B spermatogonial proliferation is restricted. A novel scheme for human spermatogonial development is proposed that will facilitate further research in this field, the understanding of cases of infertility and the development of methods to increase sperm output

SP854EVALUATION OF SUITABILITY OF KIDNEY FOR TRANSPLANT. HISTOMORPHOMETRIC ANALYSIS

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The integrated care pathway for melanoma: the Istituto Dermopatico dell'Immacolata experience in Rome

Introduction: The Integrated Care Pathway (ICP) represents a multidisciplinary outline of anticipated care, placed in an appropriate timeframe, to support patients with specific conditions or symptoms. The aim of this paper is to define the ICP for patients with melanoma referring to the "Istituto Dermopatico dell'Immacolata-IRCCS di Roma e Villa Paola" ("Center"). Methods and results: A multidisciplinary group (oncologists, dermatologists, surgeons, pathologists etc.) was defined as well as a facilitator to act as a link between all experts. The first step of ICP development was a review of current practice for patients with melanoma referring to the Center. This first step had the scope to define the multidisciplinary process map (a "picture" of the care plan) for patients with melanoma. The process map defined: i) the activities performed during delivery of care to the patients, ii) the responsibilities for these activities and iii) potential problem areas or opportunities for improvements. The process map formed the basis of the final ICP document. Conclusion: The adoption of melanoma ICP will allow the multidisciplinary group to ensure that clinical guidelines and available evidence are incorporated into everyday practice. (Oncology, HTA & Market Access

Cortical Representation of Lateralized Grasping in Chimpanzees (Pan troglodytes): A Combined MRI and PET Study

Functional imaging studies in humans have localized the motor-hand region to a neuroanatomical landmark call the KNOB within the precentral gyrus. It has also been reported that the KNOB is larger in the hemisphere contralateral to an individual's preferred hand, and therefore may represent the neural substrate for handedness. The KNOB has also been neuronatomically described in chimpanzees and other great apes and is similarly associated with handedness. However, whether the chimpanzee KNOB represents the hand region is unclear from the extant literature. Here, we used PET to quantify neural metabolic activity in chimpanzees when engaged in unilateral reach-and-grasping responses and found significantly lateralized activation of the KNOB region in the hemisphere contralateral to the hand used by the chimpanzees. We subsequently constructed a probabilistic map of the KNOB region in chimpanzees in order to assess the overlap in consistency in the anatomical landmarks of the KNOB with the functional maps generated from the PET analysis. We found significant overlap in the anatomical and functional voxels comprising the KNOB region, suggesting that the KNOB does correspond to the hand region in chimpanzees. Lastly, from the probabilistic maps, we compared right- and left-handed chimpanzees on lateralization in grey and white matter within the KNOB region and found that asymmetries in white matter of the KNOB region were larger in the hemisphere contralateral to the preferred hand. These results suggest that neuroanatomical asymmetries in the KNOB likely reflect changes in connectivity in primary motor cortex that are experience dependent in chimpanzees and possibly humans

Experimental investigation on cyclic response of RC elements repaired by CFRP external reinforcing systems

This paper deals with the experimental results of an investigation aimed at studying cyclic response of half scaled RC specimens previously damaged and then repaired with externally bonded carbon fiber reinforced polymer sheets. The research involved the test of ten specimens. Two of them were tested without any external strengthening material in order to provide a reference for the response of repaired specimens. These latter were tested after a previous damaging procedure and a subsequent repair intervention with fiber reinforced polymer composites. The parameters under investigation were the level of initial damage, the strengthening configuration, and the level of axial load. Test results have pointed out effectiveness of the adopted strengthening systems, since repaired specimens exhibited better mechanical responses than the unstrengthened ones