Modeling the Geologic History of Mt. Sharp

Gale is an approximately 155 km diameter crater located on the martian dichotomy boundary (5 deg S 138 deg E). Gale is estimated to have formed 3.8 - 3.5 Gya, in the late Noachian or early Hesperian. Mt. Sharp, at the center of Gale Crater, is a crescent shaped sedimentary mound that rises 5.2 km above the crater floor. Gale is one of the few craters that has a peak reaching higher than the rim of the crater wall. The Curiosity rover is currently fighting to find its way across a dune field at the northwest base of the mound searching for evidence of habitability. This study used orbital images and topographic data to refine models for the geologic history of Mt. Sharp by analyzing its morphological features. In addition, it assessed the possibility of a peak ring in Gale. The presence of a peak ring can offer important information to how Mt. Sharp was formed and eroded early in Gale's history

Using qualitative behaviour assessment (QBA) to explore the emotional state of horses and its association with human-animal relationship

This study aimed to apply qualitative behaviour assessment (QBA) to horses farmed in single boxes, in order to investigate their emotional state and explore its association with indicators of human-animal relationship. A fixed list of 13 QBA descriptive terms was determined. Three assessors experienced with horses and skilled in measuring animal behaviour underwent a common training period, consisting of a theoretical phase and a practical phase on farm. Their inter-observer reliability was tested on a live scoring of 95 single stabled horses. Principal Component Analysis (PCA) was conducted to analyse QBA scores and identify perceived patterns of horse expression, both for data obtained in the training phase and from the on-farm study. Given the good level of agreement reached in the training phase (Kendall W\u202f=\u202f0.76 and 0.74 for PC1 and PC2 scores respectively), it was considered acceptable in the subsequent on-farm study to let these three observers each carry out QBA assessments on a sub-selection of a total of 355 sport and leisure horses, owned by 40 horse farms. Assessment took place immediately after entering the farms: assessors had never entered the farms before and were unaware of the different backgrounds of the farms. After concluding QBA scoring, the assessors further evaluated each horse with an avoidance distance test (AD) and a forced human approach test (FHA). A MANOVA test was used to assess the association of the AD and FHA tests with the on-farm QBA PC scores. The QBA approach described in this paper was feasible on farm and showed good acceptability by owners. In the analysis of on-farm QBA scores, the first Principal Component ranged from relaxed/at ease to uneasy/alarmed, the second Component ranged from curious/pushy to apathetic. Horses perceived as more relaxed/at ease with QBA showed less avoidance during the AD test (P\u202f=\u202f0.0376), and responded less aggressively and fearfully to human presence in the FHA test (P\u202f<\u202f0.0001). Our results support the hypothesis that QBA is sensitive to the quality of human contact in horses

Improving strain diagnosis of prion disease by diffusion MRI and biophysical modelling

Sporadic Creutzfeldt–Jakob disease (sCJD) is the most common form of prion disease, characterized by five different strains, presenting intracellular vacuoles with different diameter/distribution. Unfortunately, no reliable non-invasive method for strain identification currently exists. Here we provide the first quantitative maps of MR-measured vacuolar diameter/density in five sCJD patients, using multishell diffusion MRI and biophysical modelling. Results show distribution of small and larger vacuoles in the brain lesions of each patient, presumably corresponding to different sCJD strains, and absence of vacuoles in five age-matched healthy controls. If validated, this method would be extremely valuable for non-invasive diagnosis of sCJD strain

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR &lt; 60 mL/min/1.73 m2) or eGFR reduction &gt; 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR &lt; 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR &gt; 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

Crack propagation modeling in functionally graded materials using Moving Mesh technique and interaction integral approach

This paper presents a novel FE modeling approach based on Moving Mesh technique to reproduce crack propagation mechanisms in Functionally Graded Materials. The moving mesh is consistent with the Arbitrary Lagrangian-Eulerian formulation, which is suited to handle growing random cracks, avoiding extensive remeshing processes. This approach is based on the Interaction Integral Method to extract the mixed-mode Stress Intensity Factors, which are necessary to establish crack onset conditions and propagation direction. Among the different available options for FGM, the incompatibility formulation is adopted. The proposed scheme reproduces the propagation mechanisms by moving the computational nodes around the crack tip, according to standard fracture criteria. Mesh regularization technique based on proper rezoning equations ensures the consistency of the motion, reducing mesh distortion. The reliability of the proposed method is evaluated through comparisons with experimental data and existing numerical approaches. The computational efficiency is checked through parametric analyses on mesh discretization and accuracy in the prediction of the crack path and fracture variables. The results show how the proposed method could represent a valid tool to simulate the propagation mechanisms in FGM, in which heterogeneous macro-properties involve complex crack paths

A detailed micro-model for brick masonry structures based on a diffuse cohesive-frictional interface fracture approach

In the past decades, the mechanical behavior of brick masonry material has been largely investigated using different modeling strategies, ranging from purely microscopic to purely macroscopic ones. The so-called simplified micro-modeling approaches, in which the behavior of mortar joints and brick/mortar interfaces is lumped in discontinuous elements, are commonly judged as very effective for accurately representing the interaction between the masonry constituents with an acceptable computational burden. However, they completely disregard the competition between brick/mortar decohesion and mortar cracking, whose role is not negligible, especially in presence of sufficiently thick joints and/or high-strength mortars. In this work, a detailed micro-modeling approach is proposed for the nonlinear analysis of brickworks subjected to in-plane loads. Such an approach allows failure to occur at the brick/mortar interface level and/or inside the mortar layer, while keeping the discrete nature of fracture phenomena. For this purpose, a novel diffuse cohesive-frictional interface approach for joints is presented, able to simulate multiple micro-crack onset and propagation along a-priori unknown paths. Suitable comparisons with a simplified micro-model are provided to validate the proposed approach. Moreover, a good agreement with the experimental outcomes is found, thereby assessing the reliability of the present fracture-based detailed micro-model in the numerical prediction of masonry strength under complex loading conditions

Cardiovascular medicine heart failure (CVM-HF) index as prognostic model for candidates to MitraClip therapy

Transcatheter MitraClip repair is a new tool for the management of severe mitral regurgitation in patients at very high risk for conventional surgery. Aim of our study was reporting one-year clinical outcomes in candidates to MitraClip procedures, divided into three groups according to the cardiovascular medicine heart failure (CVM-HF) index. The study population consists of 46 consecutive patients, divided, in accordance with CVM-HF index, as follows: one patient in the low-risk category (group A); 27 patients in the medium-risk (group B) and 18 patients in high-risk category (group C). The primary study endpoint was a combined of all-cause mortality and re-hospitalization rate. Secondary endpoints were all-cause mortality and cardiac mortality. Patients of group B and group C were compared. Regarding the primary endpoint, patients in group C had significantly poorer outcomes than patients in group B, with a 12-month survival freedom from events of 44.4  and 74.1 %, respectively (log-rank test, p = 0.039); survival freedom from cardiac mortality was 100 and 83.3 % in group B and C, respectively (log-rank test, p = 0.027). One-year survival free from re-hospitalization was 74.1 % in group B and 39.9 % in group C (log-rank test; p = 0.036). Survival free from all-cause of mortality was 92.6 and 77.8 %, respectively (log-rank test; p = 0.129). In our initial experience the CVM-HF index showed to be valuable for understanding if the patient with advanced heart failure and functional mitral regurgitation can really benefit by MitraClip therapy

Over three decades of natural history of limb girdle muscular dystrophy type R1/2A and R2/2B: Mathematical modelling of a multifactorial study

We aimed to describe the natural history of Limb Girdle Muscular Dystrophy type 2A and 2B over more than three decades by considering muscular strength, motor, cardiac and respiratory function. 428 visits of nineteen 2A and twenty 2B patients were retrospectively analysed through a regression model to create the curves of evolution with disease duration of muscle strength (through Medical Research Council grading), motor function measure scale (D1, D2 and D3 domains) and cardio-pulmonary function tests. Clinically relevant muscular and motor function alterations occurred after the first decade of disease, while mild respiratory function alterations started after the second, with preserved cardiac function. Although type 2A showed relatively stronger distal lower limb muscles, while type 2B started with relatively stronger upper limb muscles, the corresponding motor functions were similar, becoming severely compromised after 25 years of disease. This was the longest retrospective study in types 2A and 2B. It defined curves of disease evolution not only from a neuromuscular, but also from functional, cardiac, and respiratory points of view, to be used to evaluate how the natural progression is changed by therapies. Due to slow disease progression, it was not possible to identify time sensitive endpoints