Optimal decay rate for degenerate parabolic equations on noncompact manifolds

We consider an initial value problem for a doubly degenerate parabolic equation in a noncompact Riemannian manifold. The geometrical features of the manifold are coded in either a Faber-Krahn inequality or a relative Faber-Krahn inequality. We prove optimal decay and space-time local estimates of solutions. We employ a simplified version of the by now classical local approach by DeGiorgi, Ladyzhenskaya-Uraltseva, DiBenedetto which is of independent interest even in the euclidean case

Are sleep problems a risk factor for the onset of musculoskeletal pain in children and adolescents? A systematic review

Study Objectives: Musculoskeletal pain is a major burden on the society. Adults with sleep problems are at higher risk of musculoskeletal pain onset, but there is no evidence for this relationship in children and adolescents. This study aimed to systematically review prospective studies on the risk of musculoskeletal pain onset in children and adolescents with sleep problems. Methods: Five databases (MEDLINE, PsycINFO, AMED, EMBASE, and HMIC) were systematically searched to identify prospective studies that investigated if children and adolescents (aged 6–19 years) with sleep problems are at higher risk of musculoskeletal pain onset. Included studies were assessed for study quality and a best evidence synthesis was carried out on extracted data. Results: Thirteen prospective studies were identified. Overall, evidence indicates that sleep problems (quality, quantity, and day time tiredness) are not risk factors for musculoskeletal pain onset. Further analysis on specific body regions shows strong evidence that sleep problems are a risk factor for neck pain onset (only in girls) and that sleep problems are not a risk factor for the onset of widespread pain. Conclusions: Overall, sleep problems are not a risk factor for musculoskeletal pain onset in children and adolescents. Increased risk was found for some specific body regions and subgroups, but the evidence base was less strong and generally inconsistent. This review found a lack of quality in research methodology compared to research in adults, and further research with improved methodology is required

Monte Carlo study of gating and selection in potassium channels

The study of selection and gating in potassium channels is a very important issue in modern biology. Indeed such structures are known in all types of cells in all organisms where they play many important functional roles. The mechanism of gating and selection of ionic species is not clearly understood. In this paper we study a model in which gating is obtained via an affinity-switching selectivity filter. We discuss the dependence of selectivity and efficiency on the cytosolic ionic concentration and on the typical pore open state duration. We demonstrate that a simple modification of the way in which the selectivity filter is modeled yields larger channel efficiency

Microbial-derived pirite as evidence of early diagenetic processes on a Late Holocene shoreface deposits (Sulcis Iglesiente, West Sardinia, Italy)

Since Roman time, SW Sardinia was a mine district and its fluorishing industrial activity lasted few decades ago. Mine activity in the district resulted in enhanced amount of sediments transported by rivers to the coast and, one of the major concern is elucidating the mineralogical background before and after industrial activity along the present-day coasts. A 3-m long core was collected in the shoreface zone, at -13–m depth below sea level and ca. 500 m far from the coastal area located on the southern-western of Sardinia (west Mediterranean, Italy). A multidisciplinary approach was followed to study the core and two samples were collected for dating purpose. 14C analysis revealed a Late Holocene age comprises between 4320 ± 30 BP (base) and 1420 ± 30 yeas BP (close to the top). Preliminary sedimentological data show that the core is composed of medium-fine grained sand, with the presence of aligned pebbles and/or shells at the base of the strata. These strata can be interpreted as the results of major storms occurred in a shoreface setting. Pervasive early diagenetic processes and sub-oxic conditions are observed as well. The preliminary geochemical results can be summarized as follows: 1) residual metal sulphides are not detected; 2) Zn and Pb carbonates can be found in samples collected close to the beaches, 3) barite and other minerals are often concentrated in the fine fraction (<63 microns). Moreover, the microscopic analysis reveals the presence of secondary pyrite that is interpreted to be of microbial origin. Thus the microbial activity most likely plays a fundamental tool in the pervasive early digenesis of the studied core. Bacterial activity and its effect on biominerals processes and sedimentological features are actually under investigation

Are psychological symptoms a risk factor for musculoskeletal pain in adolescents?

AbstractAdolescent musculoskeletal pain is common and is associated with musculoskeletal pain in adulthood. Psychological symptoms, also common in adolescence, have been shown to be associated with musculoskeletal pain, but the current evidence is mixed and may be dependent on effect modifiers. This study investigated whether adolescents with psychological symptoms (internalizing and externalizing constructs) at age 13 years were at higher odds for musculoskeletal pain at age 17 years and whether the associations were modified by pubertal status and sex. A prospective cohort design examined data on 3865 adolescents from the Avon Longitudinal Study of Parents and Children (ALSPAC). Associations between baseline (aged 13 years) internalizing and externalizing symptoms and musculoskeletal pain at follow-up (aged 17 years) were investigated using logistic regression producing odds ratios (OR) and 95% confidence intervals (95% CI). In total 43.1% of adolescents reported musculoskeletal pain at follow-up. Externalizing symptoms at baseline increased the odds of musculoskeletal pain (OR 1.68, 95% CI 1.28, 2.20), and internalizing symptoms demonstrated a non-significant increase (OR 1.26, 95% CI 0.98, 1.62). Effect modification analysis showed an increased effect dependent on pubertal status.Conclusion: Adolescents with externalizing symptoms, and to some extent internalizing symptoms, are at increased odds of later musculoskeletal pain. Future research is now required to understand the reasons for these associations. What is Known:• Current evidence regarding the association between internalizing symptoms and externalizing symptoms and future musculoskeletal pain in adolescents is mixed. What is New:• This study found that adolescents with externalizing symptoms, and to some extent internalizing symptoms, are at increased odds for musculoskeletal pain, with an increased influence dependent on pubertal status.• These results are of interest for the development of timely preventative interventions designed to reduce the risk of musculoskeletal pain. </jats:p

Renal function is impaired in normotensive chronic HCV patients: role of insulin resistance

Renal dysfunction is an independent predictor for cardiovascular morbidity and mortality. We investigated whether chronic hepatitis C virus (HCV) infection and the related insulin resistance/hyperinsulinemia influence renal function in comparison with a group of healthy subjects and with another group with metabolic syndrome. We enrolled 130 newly diagnosed HCV outpatients matched for age and gender with 130 patients with metabolic syndrome and 130 healthy subjects. Renal function was evaluated by calculation of glomerular filtration rate (e-GFR, mL/min/1.73 m2) using the CKD-EPI equation. The following laboratory parameters were measured: fasting plasma glucose and insulin, total, LDL- and HDL-cholesterol, triglyceride, creatinine, and HOMA to evaluate insulin sensitivity. HCV patients with respect to both healthy subjects and metabolic syndrome patients have a decreased e-GFR: 86.6 ± 16.1 vs 120.2 ± 23.1 mL/min/1.73 m2 (P &lt; 0.0001) and 94.9 ± 22.6 mL/min/1.73 m2 (P = 0.003), respectively. Regarding biochemical variables, HCV patients, in comparison with healthy subjects, have a higher triglyceride level, creatinine, fasting insulin and HOMA (3.4 ± 1.4 vs 2.6 ± 1.3; P &lt; 0.0001). At linear regression analysis, the correlation between e-GFR and HOMA is similar in the metabolic syndrome (r = -0.555, P &lt; 0.0001) and HCV (r = -0.527, P &lt; 0.0001) groups. At multiple regression analysis, HOMA is the major determinant of e-GFR in both groups, accounting for, respectively, 30.8 and 27.8 % of its variation in the metabolic syndrome and HCV. In conclusion, we demonstrate that HCV patients have a significant reduction of e-GFR and that insulin resistance is the major predictor of renal dysfunction