Physical interpretation of gauge invariant perturbations of spherically symmetric space-times

By calculating the Newman-Penrose Weyl tensor components of a perturbed spherically symmetric space-time with respect to invariantly defined classes of null tetrads, we give a physical interpretation, in terms of gravitational radiation, of odd parity gauge invariant metric perturbations. We point out how these gauge invariants may be used in setting boundary and/or initial conditions in perturbation theory.Comment: 6 pages. To appear in PR

Adsorption of human fibrinogen and albumin onto hydrophobic and hydrophilic Ti6Al4V powder

Adsorption of proteins on solid surfaces has been widely studied because of its importance in various biotechnological, medical and technical applications, such as medical implants or biosensors. One of the main problems is the adsorption-induced conformational changes because they often modify the biological activity of the proteins, which is believed to be a key factor on the subsequent cellular adhesion. The aim of this work is the study of the adsorption of human fibrinogen (Fg) and human serum albumin (HSA) onto Ti6Al4V particles, commercially available on different size, that are used to elaborate scaffolds to provide structural support to cell proliferation, promoting tissue development and bone regeneration among others. The study was done through the analysis of the adsorption isotherms and the electrical characterization of surfaces after adsorption in terms of the zeta potential (ζ). From this analysis it seems that Fg adsorbs preferentially vertically oriented (end-on) and HSA moves sequentially over the surface of the Ti6Al4V particles through dimmer formation, allowing adsorption progress over this initial bilayer. The zeta potential values of both proteins remain constant when the monolayer is formed. The study also extends the analysis of both adsorption behaviour and ζ potential characterization factors to the influence of the substrate hydrophobicity as this property can be modified for the Ti6Al4V by irradiating it with ultraviolet light (UV-C) without changes on its chemical composition [1], [2]. Differences at low protein concentrations were found for both isotherms and zeta-potential values

Serum HER-2 concentration is associated with insulin resistance and decreases after weight loss.

HER2/neu is a member of the epidermal growth factor receptor family easily detectable in the serum of cancer patients. We aimed to evaluate circulating HER-2 concentrations in association with insulin resistance in healthy and obese subjects. METHODS: Insulin sensitivity (minimal model) and serum HER-2 concentrations were evaluated in a cross sectional study in men (cohort 1, n = 167) and longitudinally after weight loss in obese subjects (cohort 2, n = 30). RESULTS: Serum HER-2 concentrations were positively associated with BMI and waist circumference (both r = 0.18, p = 0.02), post-load glucose (r = 0.28, p = 0.001) and fasting triglycerides (r = 0.26, p = 0.001); and negatively associated with insulin sensitivity (r = -0.29, p = 0.002, n = 109). Subjects with type 2 diabetes showed significantly increased soluble serum HER-2 concentrations. In different multivariate regression models, fasting triglycerides emerged as the factor that independently contributed to 10-11% of serum HER-2 variance.Serum HER-2 concentrations correlated significantly with fasting triglycerides and insulin sensitivity index in subjects from cohort 2. Weight loss led to a significant decrease of serum HER-2 concentrations. The change in serum HER-2 concentrations were significantly associated with the change in percent body fat and fasting triglycerides in young (below the median age of the cohort) subjects. CONCLUSIONS: Serum HER-2 concentrations might be implicated in the pathophysiology of insulin resistance and associated comorbidities

Longer breastfeeding duration is associated with lower consumption of ultraprocessed foods in a sample of spanish preschoolers: The SENDO project

Background: Breastfeeding has been linked to a higher consumption of fruit and vegetables at ages 4 to 5 years. More recently, it has been suggested that it may also be associated with lower ultraprocessed food (UPF) consumption in childhood. Objective: The aim of this study was to assess whether breastfeeding duration was associated with consumption of UPF in a sample of Mediterranean preschoolers. Design: This study involved a cross-sectional analysis of baseline information of children in the Child Follow-Up for Optimal Development cohort. Children were enrolled at ages 4 to 5 years and information was gathered through an online questionnaire completed by parents. Dietary information was collected with a previously validated semi-quantitative food frequency questionnaire and foods were classified based on the degree of processing according to the NOVA classification. Participants/setting: This study used baseline information for 806 participants enrolled in the Child Follow-Up for Optimal Development cohort between January 2015 and June 2021 in Spain. Main outcomes measures: Main study outcome measures were difference in grams per day and in the percentage of total energy intake from UPF consumption related to breastfeeding duration, and odds ratio that UPF represents a high percentage of total energy intake. Statistical analyses: Crude and multivariable adjusted estimates were calculated with generalized estimating equations to account for intracluster correlation between siblings. Results: The prevalence of breastfeeding in the sample was 84%. After adjusting for potential confounders, children who were breastfed for some time reported significantly lower consumption of UPF than children who were not breastfed at all. The mean differences were -19.2 g (95% CI -44.2 to 10.8) for children who were breastfed for <6 months, -42.5 g (95% CI -77.2 to -7.80) for those who were breastfed for 6 to 12 months, and -43.6 g (95% CI -79.8 to -7.48) for those who were breastfed for 12 months or more (P value for trend = 0.01). After adjusting for potential confounders, compared with children who were not breastfed, those who were breastfed for ≥12 months had consistently lower odds of UPF representing more than 25%, 30%, 35%, and 40% of total energy intake. Conclusions: Breastfeeding is associated with lower consumption of UPF in Spanish preschoolers

Changes in plasma fatty acid composition are associated with improvements in obesity and related metabolic disorders: A therapeutic approach to overweight adolescents

Background & aims: In recent years, obesity has reached alarming levels among children and adolescents. The study of plasma fatty acid (FA) composition, as a reflection of diet, and its associations with other parameters, that are closely linked to obesity and the cardiometabolic profile, may be useful for setting nutritional goals for obesity treatment and prevention. This study explored the relationship between plasma FA levels and body fat and cardiometabolic risk markers, in overweight adolescents. Methods: A multidisciplinary weight loss program was followed by 127 overweight and obese adolescents aged 12-17 years old. Plasma FA composition, anthropometric indicators of adiposity and biochemical parameters were analyzed at baseline, two months (the end of the intensive intervention phase) and six months (the end of the extensive phase). Results: While saturated fatty acid (SFA) and n-6 polyunsaturated fatty acid (PUFA) levels decreased significantly during the intervention, monounsaturated fatty acid (MUFA) and n-3 PUFA showed the opposite trend. The decrease in SFA C14:0 was associated with a reduction in total and LDL cholesterol, apolipoprotein B and insulin. The increase in MUFAs, especially C18:1n-9, was related to a reduction in weight, fat mass, fat mass index and glucose. Regarding PUFAs, changes in the n-3 series were not associated with any of the parameters studied, whereas the reduction in n-6 PUFA5 was directly related to weight, fat mass, total and HDL cholesterol, apolipoprotein Al, glucose and insulin, and inversely associated with diastolic blood pressure. The adolescents with greater weight loss presented significant changes in MUFAs, n-6 PUFA5 and C14:0. Conclusions: Modifications in plasma FA composition were associated with adiposity reduction and cardiometabolic profile improvement in an anti-obesity program aimed at adolescents. The changes observed in FA composition were related to the success of the treatment, since the individuals most affected by these variations were those who presented the greatest weight loss

Association between dietary and beverage consumption patterns in the SUN (Seguimiento Universidad de Navarra) cohort study

Objective: The objective of the present study was to determine the dietary patterns of a Mediterranean cohort and relate them to the observed patterns of beverage consumption. Design: Prospective cohort study. Dietary habits were assessed with a semiquantitative FFQ validated in Spain. A principal components factor analysis was used to identify dietary patterns and to classify subjects according to their adherence to these patterns. The association between adherence to each dietary pattern and beverage consumption was assessed cross-sectionally. In a longitudinal analysis (2-year follow-up), the relationship between adherence to the baseline dietary patterns and the likelihood of changing alcohol consumption was ascertained. Setting: The SUN (Seguimiento Universidad de Navarra) study is conducted in Spain. Subjects: In total, 15 073 university graduates were included in the analyses. Results: Two major dietary patterns were identified. We labelled them as ‘Western dietary pattern’ (WDP) and ‘Mediterranean dietary pattern’ (MDP). Higher adherence to the WDP was associated with higher consumption of carbonated beverages and whole-fat milk (P for trend ,0?001), while higher adherence to the MDP was associated with higher consumption of decaffeinated coffee, orange juice, other natural juices, diet carbonated drinks, low-fat milk and bottled water (P for trend ,0?001). Participants with higher adherence to the WDP were less likely to decrease their alcohol consumption during follow-up (OR between extreme quintiles50?68; 95% CI 0?56, 0?84). By contrast, participants with higher adherence to the MDP were less likely to increase their alcohol consumption (OR50?66, 95% CI 0?46, 0?95). Conclusion: In this cohort of university graduates, a healthier dietary pattern was associated with a healthier pattern of beverage consumption

Family physicians' views on participating in prevention of major depression. The predictD-EVAL qualitative study

Background The predictD intervention, a multicomponent intervention delivered by family physicians (FPs), reduced the incidence of major depression by 21% versus the control group and was cost-effective. A qualitative methodology was proposed to identify the mechanisms of action of these complex interventions. Purpose To seek the opinions of these FPs on the potential successful components of the predictD intervention for the primary prevention of depression in primary care and to identify areas for improvement. Method Qualitative study with FPs who delivered the predictD intervention at 35 urban primary care centres in seven Spanish cities. Face-to-face semi-structured interviews adopting a phenomenological approach. The data was triangulated by three investigators using thematic analysis and respondent validation was carried out. Results Sixty-seven FPs were interviewed and they indicated strategies used to perform the predictD intervention, including specific communication skills such as empathy and the activation of patient resources. They perceived barriers such as lack of time and facilitators such as prior acquaintance with patients. FPs recognized the positive consequences of the intervention for FPs, patients and the doctor-patient relationship. They also identified strategies for future versions and implementations of the predictD intervention. Conclusions The FPs who carried out the predictD intervention identified factors potentially associated with successful prevention using this program and others that could be improved. Their opinions about the predictD intervention will enable development of a more effective and acceptable version and its implementation in different primary health care settings

Ultrasonic evidence of an uncorrelated cluster formation temperature in manganites with first-order magnetic transition at T_C

Ultrasonic attenuation and phase velocity measurements have been carried out in the ferromagnetic perovskites La_{2/3}Ca_{1/3}MnO_3 and La_{2/3}Sr_{1/3}MnO_3. Data show that the transition at the Curie temperature, T_C, changes from first- to second-order as Sr replaces Ca in the perovskite. The compound with first-order transition shows also another transition at a temperature T* > T_C. We interpret the temperature window T_C < T < T* as a region of coexistence of a phase separated regime of metallic and insulating regions, in the line of recent theoretical proposals.Comment: 4 pages, 2 figure

Assessing Face Validity of the HexCom Model for Capturing Complexity in Clinical Practice : a Delphi study

Funding: This research was funded by INSTITUT CATALÀ DE LA SALUT, grant number 7Z19/008.Capturing complexity is both a conceptual and a practical challenge in palliative care. The HexCom model has proved to be an instrument with strong reliability and to be valid for describing the needs and strengths of patients in home care. In order to explore whether it is also perceived to be helpful in enhancing coordinated and patient-centred care at a practical level, a methodological study was carried out to assess the face validity of the model. In particular, a Delphi method involving a group of 14 experts representing the full spectrum of healthcare professionals involved in palliative care was carried out. The results show that there is a high level of agreement, with a content validity index-item greater than 0.92 both with regard to the complexity model and the HexCom-Red, HexCom-Basic, and the HexCom-Clin instruments, and higher than 0.85 regarding the HexCom-Figure and the HexCom-Patient instruments. This consensus confirms that the HexCom model and the different instruments that are derived from it are valued as useful tools for a broad range of healthcare professional in coordinately capturing complexity in healthcare practice

Equation of state of cosmic strings with fermionic current-carriers

The relevant characteristic features, including energy per unit length and tension, of a cosmic string carrying massless fermionic currents in the framework of the Witten model in the neutral limit are derived through quantization of the spinor fields along the string. The construction of a Fock space is performed by means of a separation between longitudinal modes and the so-called transverse zero energy solutions of the Dirac equation in the vortex. As a result, quantization leads to a set of naturally defined state parameters which are the number densities of particles and anti-particles trapped in the cosmic string. It is seen that the usual one-parameter formalism for describing the macroscopic dynamics of current-carrying vortices is not sufficient in the case of fermionic carriers.Comment: 30 pages, 15 figures, uses ReVTeX, equation of state corrected, comments and references added. Accepted for publication in Phys. Rev.