Effective field description of the Anton-Schmidt cosmic fluid

The effective theory of the Anton-Schmidt cosmic fluid within the Debye approximation is investigated. In this picture, the universe is modeled out by means of a medium without cosmological constant. In particular, the Anton-Schmidt representation of matter describes the pressure of crystalline solids under deformations imposed by isotropic stresses. The approach scheme is related to the fact that the universe deforms under the action of the cosmic expansion itself. Thus, we frame the dark energy term as a function of scalar fields and obtain the corresponding dark energy potential $V(\varphi)$. Different epochs of the universe evolution are investigated in terms of the evolution of $\varphi$. We show how the Anton-Schmidt equation of state is capable of describing both late and early epochs of cosmic evolution. Finally, numerical bounds on the Anton-Schmidt model with $n=-1$ are derived through a Markov Chain Monte Carlo analysis on the combination of data coming from type Ia Supernovae, observations of Hubble parameter and baryon acoustic oscillations. Statistical comparison with the $\Lambda$CDM model is performed by the AIC and BIC selection criteria. Results are in excellent agreement with the low-redshift data. A further generalization of the model is presented to satisfy the theoretical predictions at early-stage cosmology.Comment: 13 pages, Accepted for publication in Phys. Rev.

De Sitter-like configurations with asymptotic quintessence environment

We examine a spherically-symmetric class of spacetimes carrying vacuum energy, while considering the influence of an external dark energy environment represented by a non-dynamical quintessence field. Our investigation focuses on a specific set of solutions affected by this field, leading to distinct kinds of spacetime deformations, resulting in regular, singular, and wormhole solutions. We thoroughly discuss the underlying physics associated with each case and demonstrate that more complex deformations are prone to instability. Ultimately, we find that our results lead to an \emph{isotropic de Sitter-like solution} that behaves as a quintessence fluid. To achieve this, we investigate the nature of the corresponding fluid, showing that it cannot provide the sound speed equal to a constant equation of state near the center. Consequently, we reinterpret the fluid as a slow-roll quintessence by investigating its behavior in asymptotic regimes. Further, we explore the potential implications of violating the isotropy condition on the pressures and we finally compare our findings with the de Sitter and Hayward solutions, highlighting both the advantages and disadvantages of our scenarios.Comment: 14 pages, 4 figures, 1 tabl

Constraining primordial black holes as fraction of dark matter through accretion disk luminosity

In this paper, we consider the hypothesis that fractions of dark matter could be constituted by primordial black holes (PBHs). To test this possibility, we work out the observational properties of a static black hole embedded in the dark matter envelope made of a PBH source. The corresponding modifications of geometry due to such a physical system are investigated, with particular focus on the accretion disk luminosity in spiral galaxies. The impact of the PBH presence is analyzed through modification of the disk luminosity and kinematic quantities. Thus, we discuss possible constraints on the PBH abundance in view of the most recent theoretical bounds. The results of our study indicate that suitable PBH masses are $M_\text{PBH}\in[10^6,10^{12}]M_\odot$ for PBH fractions $f_\text{PBH}\in[10^{-3},1]$. In particular, a comparison with the predictions of the exponential sphere density profile for dark matter suggests that the best-matching configuration is achieved for $f_\text{PBH}=1$ and $M_\text{PBH}=10^6 M_\odot$. Consequences with respect to the current knowledge on primordial black hole physics are discussed.Comment: 9 pages, 6 figure

Superficial cervical plexus blockade improves pain control after thyroidectomy: A randomized controlled trial

OJECTIVES: The aim was to evaluate the ability of bilateral superficial cervical plexus blockade to control pain and to reduce the side effects of general anesthesia in patients submitted to thyroidectomy. METHODS: In this randomized controlled trial, we prospectively studied 100 consecutive patients who underwent total thyroidectomy. The simple random patient sample was divided into two groups: 50 patients received general anesthesia alone (group 1 [G1]), and 50 patients received general anesthesia with bilateral superficial cervical plexus blockade (group 2 [G2]). Statistical analyses were performed, and a 5% significance level was adopted. RESULTS: The mean arterial blood pressure and heart rate were 12% lower in G2 patients than in G1 patients 60 minutes after surgery (101 mmHg for G1 vs. 92.3 mmHg for G2; po0.001). G2 patients reported less pain than G1 patients, and opioid consumption was lower in G2 patients than in G1 patients, not upon postanesthesia care unit arrival, but at 30 minutes (2% vs. 34%; po0.001, respectively), 45 minutes (0% vs. 16%; p=0.006, respectively), and 4 hours postoperatively (6% vs. 20%; p=0.037, respectively). The incidence of nausea and vomiting was lower in G2 patients than in G1 patients from 45 minutes (0% vs. 16%; p=0.006, respectively) to 8 hours postoperatively (0% vs. 14%; p=0.012, respectively). CONCLUSIONS: The present study demonstrated that the combination of bilateral superficial cervical plexus blockade with general anesthesia for thyroidectomy is feasible, safe, and effective for achieving pain control and improving patient outcomes

O abraço cruel da dor: a endometriose e as suas representações

Endometriosis is a chronic disease of the female genital tract, the etiology of which is still unclear. The purpose of this paper is to analyze, from a biopsychosocial perspective, the structure of social representations of endometriosis of women with this disease and healthy women. To this end, an exploratory survey was conducted by administering an online questionnaire. The results made it possible to identify those particular type of social representations, the controversies, articulated differently and often contradictory in their peripheral elements. These results provide a useful basis for the construction of intervention strategies to avoid the “epistemological purgatory” in which many women are forced to live due to the discrepancy between the subjective experience of endometriosis and its expert knowledge.La endometriosis es una enfermedad crónica del aparato genital femenino cuya etiología aún no está clara. El objetivo de este trabajo es analizar, desde una perspectiva biopsicosocial, la estructura de las representaciones sociales de la endometriosis entre mujeres con esta enfermedad y mujeres sanas. Para ello, se realizó una encuesta exploratoria mediante un cuestionario online. Los resultados permitieron identificar ese tipo particular de representaciones sociales, las polémicas, articuladas de manera diferente y a menudo contradictoria en sus elementos periféricos. Estos resultados constituyen una base útil para la construcción de estrategias de intervención destinadas a evitar el “purgatorio epistemológico” en el que muchas mujeres se ven obligadas a vivir debido a la discrepancia entre la experiencia subjetiva de la endometriosis y el conocimiento experto de la misma.L’endométriose est une maladie chronique de l’appareil génital féminin dont l’étiologie n’est pas encore élucidée. L’objectif de ce travail est d’analyser, dans une perspective biopsychosociale, la structure des représentations sociales de l’endométriose chez les femmes atteintes de cette maladie et chez les femmes saines. Pour faire ça, une enquête exploratoire a été menée au moyen d’un questionnaire en ligne. Les résultats ont permis d’identifier un type particulier de représentations sociales, les représentations polémiques, articulées différemment et souvent contradictoires dans leurs éléments périphériques. Ces résultats fournissent une base utile pour construire des stratégies d’intervention afin d’éviter le «purgatoire épistémologique» dans lequel de nombreuses femmes sont contraintes de vivre en raison du décalage entre leur expérience subjective de l’endométriose et la connaissance qu’en ont les experts.A endometriose é uma doença crónica do aparelho genital feminino, cuja etiologia ainda não está esclarecida. O objetivo deste trabalho é analisar, numa perspectiva biopsicossocial, a estrutura das representações sociais da endometriose entre mulheres com esta doença e mulheres saudáveis. Para o efeito, foi realizado um inquérito exploratório através de um questionário online. Os resultados permitiram identificar um tipo particular de representações sociais, as polémicas, articuladas de forma diferente e muitas vezes contraditória nos seus elementos periféricos. Estes resultados constituem uma base útil para a construção de estratégias de intervenção para evitar o “purgatório epistemológico” em que muitas mulheres são obrigadas a viver devido à discrepância entre a sua experiência subjetiva da endometriose e o seu conhecimento especializado da mesma

Enhanced Morbidity of Pectoralis Major Myocutaneous Flap Used for Salvage after Previously Failed Oncological Treatment and Unsuccessful Reconstructive Head and Neck Surgery

Introduction. The reconstruction of complex cervicofacial defects arising from surgical treatment for cancer is a real challenge for head and neck surgeons, especially in salvage reconstruction surgery and/or failed previous reconstruction. The pectoralis major myocutaneous flap (PMMF) has been widely used in these specific situations due to its reliability and low rate of failure or complications. Objectives. Identify factors that determine complications and influence the final outcome of the reconstructions with PMMF in salvage cancer surgery or in salvage reconstruction. Methods. A cross-sectional study design was used to evaluate a sample including 17 surgical patients treated over a period of ten years that met the inclusion criteria. Results. Reconstruction was successful in 13 cases (76.5%), with two cases of partial flap loss and no case of total loss. Complications occurred in 13 cases (76.5%) and were specifically related to the flap in nine instances (52.9%). An association was identified between the development of major complications and reconstruction of the hypopharynx (P = 0.013) as well as in patients submitted to surgery in association with radiation therapy as a previous cancer treatment (P = 0.002). The former condition is also associated with major reconstruction failure (P = 0.018). An even lower incidence of major complications was noted in patients under the age of 53 (P = 0.044). Conclusion. Older patients, with hypopharyngeal defects and submitted to previous surgery plus radiation therapy, presented a higher risk of complications and reconstruction failure with PMMF

Non-Invasive Identification of Atrial Fibrillation Driver Location Using the 12-lead ECG: Pulmonary Vein Rotors vs. other Locations

Atrial fibrillation (AF) is an irregular heart rhythm due to disorganized atrial electrical activity, often sustained by rotational drivers called rotors. In the present work, we sought to characterize and discriminate whether simulated single stable rotors are located in the pulmonary veins (PVs) or not, only by using non-invasive signals (i.e., the 12-lead ECG). Several features have been extracted from the signals, such as Hjort descriptors, recurrence quantification analysis (RQA), and principal component analysis. All the extracted features have shown significant discriminatory power, with particular emphasis to the RQA parameters. A decision tree classifier achieved 98.48% accuracy, 83.33% sensitivity, and 100% specificity on simulated data.Clinical Relevance-This study might guide ablation procedures, suggesting doctors to proceed directly in some patients with a pulmonary veins isolation, and avoiding the prior use of an invasive atrial mapping system

Histomorphometry of Bone after Intentionally Exposed Non-Resorbable d-PTFE Membrane or Guided Bone Regeneration for the Treatment of Post-Extractive Alveolar Bone Defects with Implant-Supported Restorations: A Pilot Randomized Controlled Trial

Aim: The aim of the present study was to investigate quantitative histological examination of bone reconstructed with non-resorbable high-density polytetrafluoroethylene membrane (d-PTFE), left intentionally exposed in post extraction sockets grafted with anorganic bone material, and removed after four weeks, versus extraction and guided bone regeneration (GBR), performed two months later. Materials and Methods: This study was designed as a multicenter randomized controlled trial of parallel-group design. Patients were selected and consecutively treated in three centers in Italy. Patients randomly received intentionally exposed non-resorbable d-PTFE membrane (group A), or guided bone regeneration (group B), to treat post-extractive alveolar bone defects with implant-supported restorations. Outcomes were: the implant failure, any mechanical and biological complications, patient satisfaction, and qualitative and histomorphometric evaluation of the collected bone samples. Results: Eighteen patients were consecutively enrolled in the trial. Of these, six out of 18 patients were male. All the included patients were treated according to the allocated interventions, and no drop out occurred. No implant failure and no complications were experienced, and all the patients were fully satisfied with the function and aesthetic of their implant-supported restoration, without difference between groups. Morphological analysis revealed no sign of tissue reaction, such as fibrosis or necrosis. Regenerated bone was well mineralized in both groups, but it seemed more mature in group B than in group A. Three samples showed a minimal number of lymphocytes. Several blood vessels of small size occupied the medullary spaces, where the tissue resulted in more maturity, indicating the activity of the tissue in progress. The histomorphometric evaluation showed no statistically significant differences in the tissue volume fractions between the two groups of patients. Conclusions: With the limitation of the present study, buccal plate reconstruction with an intentionally exposed non-resorbable membrane is an effective and easy procedure for regenerating a resorbed buccal bone plate, reducing the need for guided bone regeneration