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3.
Phys Rev Lett ; 126(9): 091101, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33750144

RESUMEN

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

4.
Soft Matter ; 17(13): 3733-3744, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33704317

RESUMEN

We propose three different techniques to synthesize anisotropic magnetic supraparticles for their incorporation in the formulation of magnetorheological fluids with novel potential applications. The techniques include microtransfer molding, electrodeposition and microfluidic flow-focusing devices. Although the yield of these methods is not large, with their use, it is possible to synthesize supraparticles with anisotropy in both their magnetic content and shape. The magnetorheological characteristics (yield stress) of the resulting field-induced structures were computed using finite element method simulations and demonstrated to be strongly dependent on the microstructural anisotropy of the supraparticles. In anisotropic particles, the simulated yield stress is always larger than that of the isotropic ones consisting of magnetically homogeneous spherical particles.

5.
Mater Sci Eng C Mater Biol Appl ; 122: 111933, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33641924

RESUMEN

The most pressing need in cartilage tissue engineering (CTE) is the creation of a biomaterial capable to tailor the complex extracellular matrix of the tissue. Despite the standardized used of polycaprolactone (PCL) for osteochondral scaffolds, the pronounced stiffness mismatch between PCL scaffold and the tissue it replaces remarks the biomechanical incompatibility as main limitation. To overcome it, the present work was focused in the design and analysis of several geometries and pore sizes and how they affect cell adhesion and proliferation of infrapatellar fat pad-derived mesenchymal stem cells (IPFP-MSCs) loaded in biofabricated 3D thermoplastic scaffolds. A novel biomaterial for CTE, the 1,4-butanediol thermoplastic polyurethane (b-TPUe) together PCL were studied to compare their mechanical properties. Three different geometrical patterns were included: hexagonal (H), square (S), and, triangular (T); each one was printed with three different pore sizes (PS): 1, 1.5 and 2 mm. Results showed differences in cell adhesion, cell proliferation and mechanical properties depending on the geometry, porosity and type of biomaterial used. Finally, the microstructure of the two optimal geometries (T1.5 and T2) was deeply analyzed using multiaxial mechanical tests, with and without perimeters, µCT for microstructure analysis, DNA quantification and degradation assays. In conclusion, our results evidenced that IPFP-MSCs-loaded b-TPUe scaffolds had higher similarity with cartilage mechanics and T1.5 was the best adapted morphology for CTE.


Asunto(s)
Células Madre Mesenquimatosas , Ingeniería de Tejidos , Cartílago , Adhesión Celular , Proliferación Celular , Poliésteres , Porosidad , Andamios del Tejido
7.
Environ Pollut ; 269: 116093, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33280914

RESUMEN

Laboratory experiments with intact sediment cores from a hypertrophic very windy exposed shallow lake were conducted to assess the combined effect of anoxia and sediment resuspension on phosphorus (P) dynamics after adding different P adsorbents (CFH-12® and Phoslock®). In this study we hypothesize that the addition of geoengineering materials will increase P retention in the sediment even at the worst physic-chemical conditions such as anoxia and sediment resuspension. Both adsorbents significantly reduced the P release from the sediments after a 54 days-anoxic incubation period (CFH-12® by 85% and Phoslock® by 98%) and even after resuspension events (CFH-12® by 84% and Phoslock® by 88%), indicating that both adsorbents are suitable P inactivating agents for restoring shallow eutrophicated lakes under such circumstances. CFH-12® did not release dissolved Fe to the water column neither after the anoxic period nor after resuspension events compared to Control (no adsorbents addition). The La concentration was significantly higher in Phoslock® (3.5-5.7 µg L-1) than in Control at all sampling days but it was not affected by resuspension. The high efficiency in P removal under anoxia and resuspension, the low risk of toxicity and the high maximum adsorption capacity makes CFH-12® a promising adsorbent for lake restoration. Nevertheless, further research about the influence of other factors (i.e. pH, alkalinity, interfering substances or strict anoxia) on the performance of CFH-12® is needed.


Asunto(s)
Lagos , Contaminantes Químicos del Agua , Sedimentos Geológicos , Humanos , Hipoxia , Fósforo , Contaminantes Químicos del Agua/análisis
9.
Ann Anat ; 232: 151582, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32810612

RESUMEN

BACKGROUND: The Chievitz's organ or juxta-oral organ is a mysterious bilateral structure, phylogenetically preserved, which develops from the mouth epithelium as an invagination that loses connection to it in the prenatal period. It is located laterally to the walls of the oral cavity in an imprecise anatomical location and receives abundant innervation from the buccal nerve. Structurally it consists of non-keratinizing squamous-like neuroepithelial cells surrounded by two layers of connective tissue with nerve fibers and different morphotypes of sensory corpuscles. Its function is completely unknown although based on its rich innervation it is assumed that works as a mechanoreceptor. METHODS: We have performed immunohistochemistry for axonal and Schwann cells, and the putative mechanoproteins ASIC2, TRPV4 and Piezo2 in sections of fetal juxta-oral organ. RESULTS: Intraparenchymatous nerve fibers and sensory corpuscles were observed as well as immunoreactivity for Piezo2 in both nerve fibers and epithelial parenchymatous cells. CONCLUSIONS: We add indirect evidence that the juxtaoral organ is a mechanoreceptor because in addition to its dense innervation, the epithelial cells and sensory nerve fibers display immunoreactivity for the mechanogated ion channel Piezo2. Based on current knowledge, the functional and clinical importance of the juxta-oral organ should be further investigated.


Asunto(s)
Mejilla/anatomía & histología , Mejilla/embriología , Mejilla/patología , Mejilla/fisiología , Feto/anatomía & histología , Humanos , Inmunohistoquímica , Canales Iónicos Activados por Ligandos/fisiología , Tejido Parenquimatoso/anatomía & histología , Tejido Parenquimatoso/inervación
10.
Actas Urol Esp (Engl Ed) ; 44(9): 617-622, 2020 Nov.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32650954

RESUMEN

INTRODUCTION: The global pandemic of COVID-19 has led to rapid implementation of telemedicine, but there is little information on patient satisfaction of this system as an alternative to face-to-face care. OBJECTIVE: To evaluate urological patient satisfaction with teleconsultation during the COVID-19 pandemic. MATERIAL AND METHODS: Observational, prospective, cross-sectional, non-interventional study carried out by telephone survey during the period considered as the peak of the pandemic (March-April 2020). A quality survey composed of 11 questions on urological care provided by physicians during the COVID-19 pandemic was conducted, selecting a representative sample of patients attended by teleconsultation. RESULTS: Two hundred patients were contacted by telephone to answer a survey on the quality of teleconsultation. The distribution of patients surveyed among the specialized consultations was homogeneous with the number of consultations cited in the period; 18% of them required assistance from family members. Sixty percent of patients avoided going to a medical center during the pandemic. Of the surveyed patients, 42% had cancelled diagnostic tests, 59% had cancelled medical consultations, 3.5% had cancelled treatments and 1% had cancelled interventions. Ten percent reported a worsening of urological symptoms during confinement. According to physicians, consultations were effectively delivered in 72% of cases, with teleconsultation being carried out by their usual urologist in 81%. Teleconsultation overall satisfaction level was 9 (IQI8-10), and 61.5% of respondents consider teleconsultation as a «health care option¼ after the healthcare crisis. CONCLUSION: Teleconsultation has been evaluated with a high level of satisfaction during the COVID-19 pandemic, offering continuous care to urological patients during the healthcare crisis. The perceived quality offers a field of optional telematic assistance in selected patients, which should be re-evaluated in a period without confinement measures.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/epidemiología , Satisfacción del Paciente/estadística & datos numéricos , Neumonía Viral/epidemiología , Consulta Remota/estadística & datos numéricos , Enfermedades Urológicas/psicología , Adulto , Anciano , Anciano de 80 o más Años , Citas y Horarios , COVID-19 , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Estudios Prospectivos , Calidad de la Atención de Salud , SARS-CoV-2 , Encuestas y Cuestionarios , Adulto Joven
11.
Int J Oral Maxillofac Surg ; 49(11): 1402-1407, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32402690

RESUMEN

The radial forearm free flap (RFFF) and ulnar forearm free flap (UFFF) are used in head and neck reconstruction because they provide a thin and pliable skin paddle as well as a long vascular pedicle. However, in spite of several studies showing the safety of the UFFF, the RFFF is more popular among reconstructive surgeons based on concerns about hand ischaemia. A prospective study was designed in which 10 UFFF and 11 RFFF surgeries were performed in 20 patients undergoing oral cavity reconstruction between January 2017 and July 2018. Hand vascular parameters were evaluated preoperatively and postoperatively using Doppler ultrasound and plethysmography. The preoperative and postoperative diameters of the radial and ulnar arteries, and the flow velocities through the remainder of the forearm artery were measured preoperatively and at 3 months postoperative. Additionally, a comparison was performed between the preoperative and postoperative fingertip perfusion values according to impedance plethysmography. The preoperative mean diameter of the radial artery (2.89±0.47mm) was significantly greater than that of the ulnar artery (2.35±0.48mm) at the level of the wrist; however, 3 months after the surgery, the mean diameters of the two arteries did not differ significantly. There were no differences in digital perfusion when a UFFF was used compared with an RFFF.


Asunto(s)
Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Antebrazo/cirugía , Humanos , Boca , Estudios Prospectivos , Arteria Radial/diagnóstico por imagen
12.
Phys Rev Lett ; 124(10): 101102, 2020 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-32216401

RESUMEN

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

13.
MRS Commun ; 10(4): 642-651, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33398240

RESUMEN

UV-initiated crosslinking of electrospun poly(ethylene) oxide (PEO)/chitosan (CS) nanofibers doped with zinc oxide nanoparticles (ZnO-NPs) was performed using pentaerythritol triaclyrate (PETA) as the photoinitiator and crosslinker agent. The influence of the addition of PETA to the PEO/CS diameter and crosslinking of nanofibers was evaluated. The effect of irradiation time on the morphology and swelling properties of the crosslinked nanofibers were investigated. For ZnO-NPs, the minimum inhibitory concentrations were found at 1 mg/mL, and the minimum bactericidal concentrations at 2 mg/mL for all the strains tested. The nanofibrous hydrogel antibacterial effect was tested. This material enters the realm of fibrous hydrogels which have potential use in several applications as in the biomedical area. SUPPLEMENTARY MATERIAL: The supplementary material for this article can be found at 10.1557/mrc.2020.74.

14.
J Stomatol Oral Maxillofac Surg ; 121(4): 330-338, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31533064

RESUMEN

INTRODUCTION: The progressive aging of European population seems to determine a change in the epidemiology, incidence and etiology of maxillofacial fractures with an increase in the frequency of old patients sustaining craniofacial trauma. The objective of the present study was to assess the demographic variables, causes, and patterns of facial fractures in elderly population (with 70 years or more). MATERIALS AND METHODS: The data from all geriatric patients (70 years or more) with facial fractures between January 1, 2013, and December 31, 2017, were collected. The following data were recorded for each patient: gender, age, voluptuary habits, comorbidities, etiology, site of facial fractures, synchronous body injuries, Facial Injury Severity Score (FISS). RESULTS: A total of 1334 patients (599 male and 735 female patients) were included in the study. Mean age was 79.3 years, and 66% of patients reported one or more comorbidities. The most frequent cause of injury was fall and zygomatic fractures were the most frequently observed injuries. Falls were associated with a low FISS value (P<.005). Concomitant injuries were observed in 27.3% of patients. Falls were associated with the absence of concomitant injuries. The ninth decade (P<.05) and a high FISS score (P<.005) were associated with concomitant body injuries too. CONCLUSIONS: This study confirms the role of falls in the epidemiology of facial trauma in the elderly, but also highlights the frequency of involvement of females, and the high frequency of zygomatic fractures.


Asunto(s)
Traumatismos Maxilofaciales , Fracturas Craneales , Fracturas Cigomáticas , Accidentes por Caídas , Anciano , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Traumatismos Maxilofaciales/epidemiología , Traumatismos Maxilofaciales/etiología , Fracturas Craneales/epidemiología , Fracturas Craneales/etiología
16.
J Stomatol Oral Maxillofac Surg ; 121(3): 226-232, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31655226

RESUMEN

INTRODUCTION: Treatment of condylar fractures in patients with atrophic edentulous mandibles is a peculiar field that has been little considered in the literature. The aim of the study was to assess the demographic and clinical variables as well as management and outcome of mandibular condylar fractures in edentulous patients with atrophic mandibles that were treated at several European departments of oral and maxillofacial surgery. METHODS: The data of all patients with fractures of the atrophic edentulous mandible from the involved maxillofacial surgical units across Europe between January 1, 2008, and December 31, 2017. Only patients that were diagnosed with condylar fractures of the edentulous atrophic mandible were included. RESULTS: A total of 52 patients met the inclusion criteria and were included in the study: 79% of patients reported one or more comorbidities. Thirty-four unilateral neck or subcondylar fractures, 9 bilateral neck or subcondylar condylar fractures, 7 unilateral head condylar fractures, and 2 bilateral head condylar fractures were diagnosed. No treatment was performed in 37 cases, whereas in 4 patients a closed treatment was decided, and 11 patients underwent open reduction and internal fixation. Outcome was considered to be satisfying in 48 patients, with no complications. CONCLUSIONS: The golden rule still remains that the diagnosis of a subcondylar or neck fracture in an edentulous patient should constitute an indication for open reduction and internal fixation. However, an appropriate choice of management options has to be individualized on a case by case basis, also depending on the patient consent.


Asunto(s)
Fracturas Mandibulares/cirugía , Europa (Continente) , Fijación Interna de Fracturas , Humanos , Mandíbula , Cóndilo Mandibular/cirugía
18.
Phys Rev Lett ; 122(17): 171301, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31107093

RESUMEN

The combination of multiple observational probes has long been advocated as a powerful technique to constrain cosmological parameters, in particular dark energy. The Dark Energy Survey has measured 207 spectroscopically confirmed type Ia supernova light curves, the baryon acoustic oscillation feature, weak gravitational lensing, and galaxy clustering. Here we present combined results from these probes, deriving constraints on the equation of state, w, of dark energy and its energy density in the Universe. Independently of other experiments, such as those that measure the cosmic microwave background, the probes from this single photometric survey rule out a Universe with no dark energy, finding w=-0.80_{-0.11}^{+0.09}. The geometry is shown to be consistent with a spatially flat Universe, and we obtain a constraint on the baryon density of Ω_{b}=0.069_{-0.012}^{+0.009} that is independent of early Universe measurements. These results demonstrate the potential power of large multiprobe photometric surveys and pave the way for order of magnitude advances in our constraints on properties of dark energy and cosmology over the next decade.

19.
Actas Urol Esp (Engl Ed) ; 43(1): 44-50, 2019.
Artículo en Inglés, Español | MEDLINE | ID: mdl-30064705

RESUMEN

INTRODUCTION: The artificial urinary sphincter (AUS) is not used extensively in the treatment of female urinary stress incontinence (USI) due to the poor reproducibility of the techniques used. We describe a new approach to laparascopic implantation, of which dissection of the vesicovaginal space is an essential step. This enables an approach under direct vision to the posterior surface of the bladder neck. MATERIAL AND METHODS: We present two cases where this approach was used. A transperitoneal approach was made in the Trendelenburg position. The main steps were: creating the vesicovaginal space until identifying the bladder neck, creating two laterovesical spaces, communicating these with the vesicovaginal space, and dissecting the anterior surface of the bladder neck, attempting to preserve the pubovesical ligament. The cuff and reservoir were inserted through the 12mm infraumbilical trocar. The connections were externalised through a left suprapubic incision and a subcutaneous tunnel created up to the labia majora where the activation pump was placed. The procedure was completed with closure of the peritoneum. It is essential to use a vaginal valve to facilitate dissection. RESULTS: Surgery time: 140 and 135minutes, with no intraoperative complications. After removing the urinary catheter, one patient had elevated postvoid residual urine volume, which was managed conservatively. Hospital stay: 72h. At 3 and 9 months the patients were fully continent. CONCLUSIONS: We present the preliminary results of laparoscopic implantation of an AUS through a vesicovaginal approach to the posterior surface of the bladder neck, which might reduce potential complications that have been observed after the routine techniques.


Asunto(s)
Laparoscopía/métodos , Implantación de Prótesis/métodos , Esfínter Urinario Artificial , Anciano , Disección/métodos , Diseño de Equipo , Femenino , Humanos , Vejiga Urinaria , Vagina , Técnicas de Cierre de Heridas
20.
Water Res ; 141: 377-386, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29807320

RESUMEN

Phosphorus (P) removal from lake/drainage waters by novel adsorbents may be affected by competitive substances naturally present in the aqueous media. Up to date, the effect of interfering substances has been studied basically on simple matrices (single-factor effects) or by applying basic statistical approaches when using natural lake water. In this study, we determined major factors controlling P removal efficiency in 20 aquatic ecosystems in the southeast Spain by using linear mixed models (LMMs). Two non-magnetic -CFH-12® and Phoslock®- and two magnetic materials -hydrous lanthanum oxide loaded silica-coated magnetite (Fe-Si-La) and commercial zero-valent iron particles (FeHQ)- were tested to remove P at two adsorbent dosages. Results showed that the type of adsorbent, the adsorbent dosage and color of water (indicative of humic substances) are major factors controlling P removal efficiency. Differences in physico-chemical properties (i.e. surface charge or specific surface), composition and structure explain differences in maximum P adsorption capacity and performance of the adsorbents when competitive ions are present. The highest P removal efficiency, independently on whether the adsorbent dosage was low or high, were 85-100% for Phoslock and CFH-12®, 70-100% for Fe-Si-La and 0-15% for FeHQ. The low dosage of FeHQ, compared to previous studies, explained its low P removal efficiency. Although non-magnetic materials were the most efficient, magnetic adsorbents (especially Fe-Si-La) could be proposed for P removal as they can be recovered along with P and be reused, potentially making them more profitable in a long-term period.


Asunto(s)
Restauración y Remediación Ambiental , Fósforo/química , Contaminantes Químicos del Agua/química , Adsorción , Óxido Ferrosoférrico/química , Sustancias Húmicas , Hierro/química , Lagos/química , Lantano/química , Modelos Lineales , Óxidos/química , Dióxido de Silicio/química , España
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