1,013 research outputs found
Extended phase space quantization of a black hole interior model in Loop Quantum Cosmology
Considerable attention has been paid to the study of the quantum geometry of
nonrotating black holes within the framework of Loop Quantum Cosmology. This
interest has been reinvigorated since the introduction of a novel effective
model by Ashtekar, Olmedo and Singh. Despite recent advances in its foundation,
there are certain questions about its quantization that still remain open. Here
we complete this quantization taking as starting point an extended phase space
formalism suggested by several authors, including the proposers of the model.
Adopting a prescription that has proven succesful in Loop Quantum Cosmology, we
construct an operator representation of the Hamiltonian constraint. By
searching for solutions to this constraint operator in a sufficiently large set
of dual states, we show that it can be solved for a continuous range of the
black hole mass. This fact seems in favour of a conventional classical limit
(at least for large masses) and contrasts with recent works that advocate a
discrete spectrum. We present an algorithm that determines the solutions in
closed form. To build the corresponding physical Hilbert space and conclude the
quantization, we carry out an asymptotic analysis of those solutions, which
allows us to introduce a suitable inner product on them.Comment: 15 page
Efficacy of Bracing on Thoracic Kyphotic Angle and Functionality in Women with Osteoporosis: A Systematic Review
[Abstract] Background and purpose: Osteoporotic hyperkyphosis is associated with adverse outcomes, such as fatigue, back pain, or reduced back extensor strength, with a negative impact on functionality and quality of life. The purpose of this review is to assess the effectiveness of spinal orthosis on these adverse effects. Methods: A systematic review following the PRISMA guidelines was performed. Inclusion criteria were (1) women with osteoporosis; (2) randomized controlled trials only; and (3) type of intervention: spinal bracing. Exclusion criteria were (1) article not written in English; (2) full-text not available; and (3) no kyphosis assessment. Quality-of-life variables such as back pain, functional variables such as back extensor strength, and osteoporotic-related variables such as lumbar spine bone mineral density were extracted and recorded before and after the intervention. The characteristics of the intervention programs were also extracted and recorded. The characteristics of studies, interventions, and participants are summarized in a table. Then, the revised Cochrane risk-of-bias tool for randomized trials (RoB 2) was used to assess the quality of the studies. Results and Discussion: Four randomized controlled trials with a low risk of bias were included (n = 326 women with osteoporosis, aged 51–93 years). Interventions consisting of wearing a dynamic hyperextension orthosis for at least two hours per day for six months improved functionality, mobility, back extensor strength, respiratory function, and reduced the thoracic kyphosis angle. Conclusions: Spinal orthosis, especially dynamic hyperextension braces, seems effective in improving the adverse outcomes of osteoporotic hyperkyphosis. It does not seem necessary to wear the orthosis during all daily activities
Experience of Preimplantation Genetic Diagnosis with HLA Matching at the University Hospital Virgen del RocĂo in Spain: Technical and Clinical Overview
Preimplantation genetic diagnosis (PGD) of genetic diseases, combined with HLA matching (PGD-HLA), is an option for couples
at risk of transmitting a genetic disease to select unaffected embryos of an HLA tissue type compatible with that of an existing
affected child. Here we present the results of our PGD-HLA program at the Department of Genetics, Reproduction and Fetal
Medicine of the University Hospital Virgen del Roc´ıo in Seville. Seven couples have participated in our program because of different
indications. Overall, 26 cycles were performed, providing a total of 202 embryos. A conclusive molecular diagnosis and HLA-typing
could be assured in 96% of the embryos. The percentage of transfers per cycle was 26.9% and the birth rate per cycle was 7.7% per
transfer. Our PGD-HLA program resulted in the birth of 2 healthy babies, HLA-identical to their affected siblings, with successful
subsequent haematopoietic stem cell (HSC) transplantations. Both HSC-transplanted children are currently doing well 48 and 21
months following transplantation, respectively. All the procedures, including HSCs umbilical cord transplantation, were performed
in our hospital
Mejoramiento de la Tenacidad de Polipropileno con nanopartĂculas de Carbonato de Calcio
ABSTRACT: Toe mechanical properties ofpolypropylene (PP)-calcium carbonate (CaCO3) nanocomposites were studied in this work. In this study stearic acid was used as a new interface modifier during the compounding of the nanocomposites with a twin screw extruder. The concentration in weight of the nanofiller in the compounds was of 1.5%, 2.5% and 5.0% respectively. Toe nanocomposites were characterized by impact resistance and tensile tests. Toe interaction between CaCOJ and stearic acid was analyzed by FTIR. Toe infrared spectra <lid not show any chemical reaction between CaCOJ and stearic acid. Toe elongation at break and impact resistance were increased in nanocomposites with interface modifier ( stearic acid in hopper ofthe extruder)
Anticipating hyperthermic efficiency of magnetic colloids using a semi-empirical model: a tool to help medical decisions
Magnetic hyperthermia, a modality that uses radio frequency heating assisted with single-domain magnetic nanoparticles, is becoming established as a powerful oncological therapy. Much improvement in nanomaterials development, to enhance their heating efficiency by tuning the magnetic colloidal properties, has been achieved. However, methodological standardization to accurately and univocally determine the colloidal properties required to numerically reproduce a specific heating efficiency using analytical expressions still holds. Thus, anticipating the hyperthermic performances of magnetic colloids entails high complexity due to polydispersity, aggregation and dipolar interactions always present in real materials to a greater or lesser degree. Here, by numerically simulating the experimental results and using real biomedical aqueous colloids, we analyse and compare several approaches to reproduce experimental specific absorption rate values. Then, we show that the relaxation time, determined using a representative mean activation energy consistently derived from four independent experiments accurately reproduces experimental heating efficiencies. Moreover, the so-derived relaxation time can be used to extrapolate the heating performance of the magnetic nanoparticles to the other field conditions within the framework of the linear response theory. We thus present a practical tool that may truly aid the design of medical decisions.Facultad de Ciencias ExactasInstituto de FĂsica La Plat
Bacteria-instructed B cells cross-prime naĂŻve CD8+ T cells triggering effective cytotoxic responses.
In addition to triggering humoral responses, conventional B cells have been described in vitro to cross-present exogenous antigens activating naĂŻve CD8+ T cells. Nevertheless, the way B cells capture these exogenous antigens and the physiological roles of B cell-mediated cross-presentation remain poorly explored. Here, we show that B cells capture bacteria by trans-phagocytosis from previously infected dendritic cells (DC) when they are in close contact. Bacterial encounter "instructs" the B cells to acquire antigen cross-presentation abilities, in a process that involves autophagy. Bacteria-instructed B cells, henceforth referred to as BacB cells, rapidly degrade phagocytosed bacteria, process bacterial antigens and cross-prime naĂŻve CD8+ T cells which differentiate into specific cytotoxic cells that efficiently control bacterial infections. Moreover, a proof-of-concept experiment shows that BacB cells that have captured bacteria expressing tumor antigens could be useful as novel cellular immunotherapies against cancer.We are grateful to advanced light microscopy and cytometry facilities of CNB
for technical supporting. The research is supported by grants: SAF2017-84091-
R, and PID2020-116393RB-I00/AEI/10.13039/501100011033, financed by MCIN,
BFERO2020.04, financed by FERO foundation and PI20/0036 from ISCIII. RGF is
supported by BES-2016-076526 from the Spanish Ministry of Economy Industry and Competitiveness, JOP is supported by fellowship LCF/BQ/SO16/
52270012 from La Caixa, BHF is supported by FPU18/00895 and AMP by
FPU18/03199 from Ministry of Science, Innovation and Universities. LdC has
been supported by Juan de la Cierva grant IJC2018-035386-I and a contract
associated to SEV-2017-0712. EVC, AMP, AMAM, and NMM belong to the Spanish National Research Council (CSIC)’s Cancer Hub. Synopsis image made with
biorender.com by Eduardo Roman Camacho and Esteban Veiga. We thanks
Prof. Dan Portnoy who kindly provided bacterial strains.S
Photodegradation of norfloxacin adsorbed on clay and carbon-clay nanomaterials: an evaluation based on antimicrobial tests
The antibiotic norfloxacin was adsorbed on clay and carbon-clay nanocomposites (MD-210 and MDac3-210-500, synthesized by hydrothermal carbonization of dextrose) but maintained its antimicrobial activity once adsorbed. To degrade it, direct (DP) and indirect (IP, with sulfate radicals) photolysis were performed. Antimicrobial activity tests were performed to evaluate the degradation generated. There were no significant differences between DP and IP for unabsorbed norfloxacin solution. The IP treatment caused a loss of antibiotic activity in all cases. For DP, the carbon samples showed better results than those of clay, evidencing the importance of oxygenated carbonaceous groups in the photolysis of norfloxacin
Pharmaceutical and Botanical Management of Pain Associated with Psychopathology: A Narrative Review
Generally, pain can be described as an unpleasant sensory or emotional experience associated with tissue damage. Chronic pain has become a public health problem because among 35 and 75% of the world population has shown the symptom. In particular, neuropathic pain has shown high comorbidity disorders such as anxiety and depression. Conventional therapies for treating pain include nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, tricyclic antidepressants, anticonvulsants, and opioids, which usually cause some side effects such as gastritis, headache, liver and kidney toxicity, and drug dependence. Conventional pharmaceuticals also tend to be expensive, and they cannot be easily afforded in developing countries, which have led to the use of natural products as an alternative treatment. In this chapter, we reviewed the current research of natural products for pain treatment. We also describe preclinical studies that assess the effect of some natural products on pain therapy, phytochemistry research, toxicity, adverse effects, and biosecurity. We also describe how conventional pain is managed and the possible use of compounds obtained from vegetable species for pain treatment
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