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Bentonite-based materials have emerged as a highly promising choice for engineered barriers in nuclear waste deep geological disposal. These materials are characterised by low permeability, high swelling capacity and effective radionuclide retardation, making them suitable for sealing underground galleries and canisters containing nuclear waste. However, the presence of technological gaps within the bentonite or the host rock can significantly influence their hydromechanical behaviour, potentially creating preferential pathways for radionuclide migration, thus affecting the overall performance of the engineered barrier. In this study, two different modelling strategies (namely, "gap" and "no-gap") to reproduce technological gaps and their effect on the hydromechanical behaviour of bentonite-based materials during intermediate saturation stages are proposed. The numerical model is used to simulate laboratory tests, and the numerical results are compared with experimental data coming from hydration test conducted under overall constant volume (isochoric) conditions. It is noteworthy that the specimen used in the experimental study is characterised by a localised gap between its side and the cell wall. The paper highlights the benefits of the "gap" numerical model, which employs interface elements to reproduce technological gaps at the side of the cell and exhibits satisfactory capabilities in reproducing the experimental swelling pressure evolution during bentonite hydration, especially during the transient wetting stages. Significant implications are expected for predicting site performance of engineered barrier systems in nuclear waste disposal applications. Highlights: The effect of technological gaps on the hydro-mechanical behaviour of bentonite-based materials for nuclear waste disposal is investigated. Two different modelling strategies, "gap" and "no-gap", are proposed to simulate the presence of technological gaps in the bentonite. The numerical results are compared with experimental data from a hydration test under constant volume conditions. The advantages of the "gap" numerical model, which can reproduce the experimental swelling pressure evolution more accurately, are demonstrated and its implications are discussed for the performance of engineered barrier systems. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to provide a better understanding of the patient-perceived effects of France's first COVID-19-related lockdown on the quality of life (QoL) of women affected by cancer, and to test an ad hoc measurement scale for evaluating quasi-individualized QoL. QoL was measured for both during (i.e., current) and before (i.e., retrospectively) the lockdown. Respondents were women registered on the research platform Seintinelles. Methods: A tool for measuring quasi-individualized QoL was adapted from the SeiQol-DW and PGI. It was distributed as part of a larger online self-questionnaire to a sample of 1303 women with a history of cancer (i.e., former or current) and with no such history. Results: Current and retrospective QoL scores were not significantly different between the two respondent groups. An analysis of reconceptualization and reprioritization revealed a cancer-specific effect: women with a history of cancer reconceptualized more, while women with no such history reprioritized more. Conclusion: Our novel ad hoc quasi-qualitative tool made it possible to assess the QoL of women with a history of cancer, a particularly vulnerable population in the context of the COVID-19 pandemic. Furthermore, it highlighted a difference in reconceptualization and reprioritization between this population and women with no such history. [ABSTRACT FROM AUTHOR]

In this paper, we construct the complex Shepard operators to approximate continuous and complex-valued functions on the unit square. We also examine the effects of regular summability methods on the approximation by these operators. Some applications verifying our results are provided. To illustrate the approximation theorems graphically we consider the real or imaginary part of the complex function being approximated and also use the contour lines of the modulus of the function. [ABSTRACT FROM AUTHOR]

One of the most pressing challenges in the clinical research of neurodegenerative diseases (NDDs) is the validation and standardization of pathophysiological biomarkers for different contexts of use (CoUs), such as early detection, diagnosis, prognosis, and prediction of treatment response. Neurofilament light chain (NFL) concentration is a particularly promising candidate, an indicator of axonal degeneration, which can be analyzed in peripheral blood with advanced ultrasensitive methods. Serum/plasma NFL concentration is closely correlated with cerebrospinal fluid NFL and directly reflects neurodegeneration within the central nervous system. Here, we provide an update on the feasible CoU of blood NFL in NDDs and translate recent findings to potentially valuable clinical practice applications. As NFL is not a disease-specific biomarker, however, blood NFL is an easily accessible biomarker with promising different clinical applications for several NDDs: (1) early detection and diagnosis (i.e., amyotrophic lateral sclerosis, Creutzfeldt–Jakob disease, atypical parkinsonisms, sporadic late-onset ataxias), (2) prognosis (Huntington's disease and Parkinson's disease), and (3) prediction of time to symptom onset (presymptomatic mutation carriers in genetic Alzheimer's disease and spinocerebellar ataxia type 3). [ABSTRACT FROM AUTHOR]

The hormone receptor-positive (estrogen and/or progesterone receptor (PR)-positive) and HER2-negative breast cancer (BC) subtype is a biologically heterogeneous entity that includes luminal A-like (LumA-like) and luminal B-like (LumB-like) subtypes. Decreased PR levels is a distinctive biological feature of LumB-like tumors. These tumors also show reduced sensitivity to endocrine therapies and poorer prognosis than LumA-like tumors. Identification of biomarkers to accurately predict disease relapse in these subtypes is crucial in order to select effective therapies. We identified the tumor suppressor PDCD4 (programmed cell death 4), located in the nucleus (NPDCD4), as an independent prognostic factor of good clinical outcome in LumA-like and LumB-like subtypes. NPDCD4-positive LumB-like tumors presented overall and disease-free survival rates comparable to those of NPDCD4-positive LumA-like tumors, indicating that NPDCD4 improves the outcome of LumB-like patients. In contrast, NPDCD4 loss increased the risk of disease recurrence and death in LumB-like compared with LumA-like tumors. This, along with our results showing that LumB-like tumors present lower NPDCD4 positivity than LumA-like tumors, suggests that NPDCD4 loss contributes to endocrine therapy resistance in LumB-like BCs. We also revealed that PR induces PDCD4 transcription in LumB-like BC, providing a mechanistic explanation to the low PDCD4 levels in LumB-like BCs lacking PR. Finally, PDCD4 silencing enhanced BC cell survival in a patient-derived explant model of LumB-like disease. Our discoveries highlight NPDCD4 as a novel biomarker in LumA- and LumB-like subtypes, which could be included in the panel of immunohistochemical markers used in the clinic to accurately predict the prognosis of LumB-like tumors. [ABSTRACT FROM AUTHOR]

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Alessandra Renieri and Anna Maria Pinto are members of the European Reference Network for rare malformation syndromes and rare intellectual and neurodevelopmental disorders, ERN-ITHACA. In the acknowledgment section author did not specify that some authors participate to a specific ERN related to the topic of the manuscript. Acknowledgement section should read as: B Acknowledgements b We thank Catherine J. Wrenn for expert editing of the manuscript and critical advice on tables and figures. [Extracted from the article]

Shepard-type rational operators based on q-integers are studied and convergence results and pointwise approximation error estimates improving previous statements are obtained. Influence of choice of q on the error estimates is also discussed. Techniques in CAGD for shape modeling of rational curves based on above operators are also presented and numerical examples are given. [ABSTRACT FROM AUTHOR]

Uniform approximation error estimates for weighted Shepard-type operators more flexible than the unweighted analogues are given. Error estimates for a linear combination of their iterates faster converging than previous ones are also showed. The results are applied in CAGD to construct Shepard-type curves useful in modeling and a weighted progressive iterative approximation technique exponentially converging. [ABSTRACT FROM AUTHOR]

First asymptotic relations of Voronovskaya-type for rational operators of Shepard-type are shown. A positive answer in some senses to a problem on the pointwise approximation power of linear operators on equidistant nodes posed by Gavrea, Gonska and Kacsó is given. Direct and converse results, computational aspects and Grüss-type inequalities are also proved. Finally an application to images compression is discussed, showing the outperformance of such operators in some senses. [ABSTRACT FROM AUTHOR]

Two operators are introduced for the weighted L approximation on the semiaxis with weight w( x) = xexp(− x), α > −1/ p, 0 < β ≤ 1, allowing a much wider class of functions than in the case of classical Szász-Mirakyan and Butzer operators. It is shown that in case 1/2 < β ≤ 1, only pointwise convergence holds, while for 0 < β ≤ 1/2, direct and converse theorems in terms of a weighted modulus of smoothness hold. Voronǒvskaya-type relations are also proved. [ABSTRACT FROM AUTHOR]

This paper is a recapitulation of the work of L. Szili and P. Vértesi [4] on multivariate Fourier series with triangular type partial sums. Namely, we give another proof for the corresponding lower estimation, which, in a way, is more direct than the previous one in [4]. [ABSTRACT FROM AUTHOR]

In [], we have introduced a new weighted type of modification of the classical Kantorovich operator. The advantage of this operator is that there is no restriction on the parameters of the weight, and the class of functions is wider than in the earlier version of the weighted operator (cf. the monograph of Ditzian and Totik []). Direct and converse theorems and a Voronovskaya-type relation were proved. Here we solve the saturation problem of the operator (Theorem 2.1). We follow the method developed in [], but the details are much more involved. A surprising fact emerges in determining the trivial class of saturation (Theorem 3.1). [ABSTRACT FROM AUTHOR]

This paper generalizes some results of L. B. Golinskii [4] on the asymptotic behaviour of reflection coefficients associated with generalized Jacobi weight functions. [ABSTRACT FROM AUTHOR]

Monitoring transport of dissolved substances in soil deposits is particularly relevant where safety is concerned, as in the case of geo-environmental barriers. Geophysical methods are very appealing, since they cover a wide domain, localising possible preferential flow paths and providing reliable links between geophysical quantities and hydrological variables. This paper describes a 3D laboratory application of electrical resistivity tomography (ERT) used to monitor solute transport processes. Dissolution and transport tests on both homogeneous and heterogeneous samples were conducted in an instrumented oedometer cell. ERT was used to create maps of electrical conductivity of the monitored domain at different time intervals and to estimate concentration variations within the interstitial fluid. Comparisons with finite element simulations of the transport processes were performed to check the consistency of the results. Tests confirmed that the technique can monitor salt transport, infer the hydro-chemical behaviour of heterogeneous geomaterials and evaluate the performances of clay barriers. [ABSTRACT FROM AUTHOR]

Pervasive Computing technologies can be successfully adopted in designing smart and enhanced healthcare services and applications. Within a typical healthcare institution, one particular facility which can greatly benefit from pervasive technologies is the Nuclear Medicine Department, where nuclear medicine diagnostic tests like PET scan and nuclear scintigraphy are routinely carried out involving the use of radioactive substances. This paper presents a pervasive healthcare system which is intended to support clinicians in handling nuclear medicine test sessions within an appropriate, safety-aware context. The proposed system also includes features to easily interoperate with heterogeneous software and databases already present in traditional hospitals. Its design lies on a methodology which integrates RFID and photoelectric sensor technologies. An experimental prototype has been implemented and tested showing the feasibility of the system in a real healthcare facility. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the efficacy of traditional treatment and minimal invasive flexible endoscopy surgery (MIFNES) in the treatment of intraventricular and subarachnoid basal cisterns neurocysticercosis (NCC). This was an observational comparative study of two independent series with a total of 140 patients with extremely severe forms of NCC from two different institutions. All 83 patients submitted for traditional treatment series received albendazole, and some of them received additionally praziquantel. Each cycle of both regimens lasted 4 weeks. The majority of these patients had at least one ventriculoperitoneal (VP) shunt. The rest 57 patients were submitted to the MIFNES treatment. The follow-up period was at least 6 months. In all patients of both series cysticercal cysts disappeared, became calcified, or were removed. Symptoms of 136 patients improved. Four patients died. The average in the quality of life measured using the Karnofsky scale improved from a mean of 52.22 and 52.44 at the beginning to 85.48 and 90.37 at 6 months ( p < 0.003), in the traditional treatment and MIFNES series, respectively. From traditional treatment, almost all patients remained with at least one VP shunt, and from the MIFNES series only 12 patients. The authors postulate that MIFNES is a good alternative for the management of intraventricular and subarachnoid basal cisterns NCC because it allows removal of most of the parasites, rapid recovery of the patients, and removal and placement of shunt under direct vision when necessary. Traditional treatment is a second option where the MIFNES procedure is not available. [ABSTRACT FROM AUTHOR]

We report a patient who suffered from brainstem injury following ventriculoperitoneal (VP) shunt placement in the fourth ventricle. A 20-year-old man with complex hydrocephalus and trapped fourth ventricle underwent a subocciptal placement of a VP shunt. Postprocedure patient developed double vision. Magnetic resonance imaging showed that the catheter was penetrating the dorsal brainstem at the level of the pontomedullary junction. Patient was referred to our Neuroendoscopic Clinic. Physical exam demonstrated pure right VI cranial nerve palsy. Patient underwent flexible endoscopic exploration of the ventricular system. Some of the endoscopic findings were severe aqueductal stenosis and brainstem injury from the catheter. Aqueductoplasty, transaqueductal approach into the fourth ventricle, and endoscopic repositioning of the catheter were some of the procedures performed. Patient recovered full neurological function. The combination of endoscopic exploration and shunt is a good alternative for patients with complex hydrocephalus. A transaqueductal approach to the fourth ventricle with flexible scope is an alternative for fourth ventricle pathology. [ABSTRACT FROM AUTHOR]

We give error estimates for the weighted approximation of functions with singularities at the endpoints on the semiaxis by some modifications of Sz\'asz--Mirakyan operators. To do so, we define a new weighted modulus of smoothness and prove its equivalence to the weighted K-functional. Also, the class of functions for which the modified Sz\'asz--Mirakyan operator can be defined will be extended to a much wider set than for the original operator. [ABSTRACT FROM AUTHOR]

We give direct and converse results for the weighted approximation of functions with endpoint or inner singularities by Bernstein operators. [ABSTRACT FROM AUTHOR]

The authors state a one-sided convergence theorem for Lagrange interpolation based on certain generalizations of Jacobi weights. In a sense the results are best possible. [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To examine the relationship between 24 h ambulatory blood pressure monitoring and three commonest anthropometric measurements for obesity—body mass index (BMI), waist-to-hip ratio (WHR) and waist circumference (W). DESIGN:: Cross-sectional survey among outpatients at the Obesity Research Center. SUBJECTS AND METHODS:: Four-hundred and sixty-one overweight or obese subjects, non-diabetic, otherwise healthy, aged 20–70 y, of either sex, were consecutively recruited. All subjects underwent 24 h ambulatory blood pressure monitoring. The population study was separated in normotensive and hypertensive males and females and the possible risk factors for hypertension (W, WHR, BMI and age) were subdivided into different classes of values. RESULTS:: Logistic regression shows that W is the most important anthropometric factor associated with the hypertensive risk. Among males with W≥102 cm the odds ratio (OR) for hypertension is three times that of males with W<94 cm using casual BP measure (OR 3.04), nearly four times higher using 24 h BP mean (OR 3.97), and even five times higher using day-time BP mean (OR 5.19). Females with W≥88 cm have a risk for hypertension twice that of females with W<80 cm, whatever BP measurement was take (casual, 24 h or day-time). Males with WHR≥0.96 and females with WHR≥0.86 show significant OR for hypertension only by 24 h BP measurement and by day-time BP measurement. BMI seems to have no significant relationship to hypertensive risk. Age shows a significant relationship to hypertensive risk only considering males aged ≥55 y and females aged ≥50 y. CONCLUSION:: The waist circumference seems to have a strong association with the risk of hypertension, principally by the ambulatory BP monitoring, when compared with casual BP measurement.International Journal of Obesity (2001) 25, 1360–1364 [ABSTRACT FROM AUTHOR]

The authors investigate the approximation of bounded functions with discontinuities of the first kind by generalized Shepard operators. Estimate for the rate of convergence at a continuity point is obtained, while at the points of discontinuity it is shown that the sequence of generalized Shepard operators is almost always divergent. It is also shown that the sequence of Cesàro means of generalized Shepard operators is convergent everywhere for bounded functions which have only discontinuities of the first kind in [0,1]. [ABSTRACT FROM AUTHOR]

In this paper, the EC-5 water sensor and the MPS-6 water potential sensor were used to measure water content and suction, respectively, to investigate the evolution of soil–water retention properties of compacted loess samples prepared at different dry densities and subjected to different numbers of wetting–drying cycles. The water retention data were integrated with a detailed microstructural investigation, including morphological analysis (by scanning electron microscopy) and pore size distribution determination (by nuclear magnetic resonance). The microstructural information obtained shed light on the double porosity nature of compacted loess, allowing the identification of the effects of compaction dry density and wetting–drying cycles at both intra- and inter-aggregate levels. The information obtained at the microstructural scale was used to provide a solid physical basis for the development of a simplified version of the water retention model presented in Della Vecchia et al. (Int J Numer Anal Meth Geomech 39: 702–723, 2015). The model, adapted for engineering application to compacted loess, requires only five parameters to capture the water retention properties of samples characterized by different compaction dry densities and subjected to different numbers of wetting–drying cycles. The comparison between numerical simulations and experimental results, both original and from the literature, shows that only one set of parameters is needed to reproduce the effects of dry density variation, while the variation of only one parameter allows the reproduction of the effects of wetting and drying cycles. With respect to the approaches presented in the literature, where ad hoc calibrations are often used to fit density and wetting–drying cycle effects, the model presented here shows a good compromise between simplicity and predictive capabilities, making it suitable for practical engineering applications. [ABSTRACT FROM AUTHOR]

A Gupta-type variant of Shepard operators is introduced and convergence results and pointwise and uniform direct and converse approximation results are given. An application to image compression improving a previous algorithm is also discussed. [ABSTRACT FROM AUTHOR]

A coupled hydromechanical code based on a distributed brittle damage material model has been developed in order to simulate hydraulic fracturing processes. As specific feature, the code does not assume the development of a discrete number of sharp cracks but considers a diffused damage that takes place under overall confinement of the system. The code is validated against a laboratory test reproducing the local effects of a hydraulic fracturing procedure. The numerical model of the laboratory test is then used to conduct a parametric analysis where the influence of the principal hydromechanical parameters on the hydraulic fracturing performance is assessed. Finally, the code is applied to simulate multiple hydraulic fracturing interventions in a large scale shale reservoir. In all applications considered, the model shows a good predictive capability in terms of damage extension. [ABSTRACT FROM AUTHOR]