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1.
J Dairy Sci ; 106(1): 407-420, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36400619

RESUMEN

Sperm motility is directly related to the ability of sperm to move through the female reproductive tract to reach the ovum. Sperm motility is a complex trait that is influenced by environmental and genetic factors and is associated with male fertility, oocyte penetration rate, and reproductive success of cattle. In this study we carried out a GWAS in Italian Holstein bulls to identify candidate regions and genes associated with variations in progressive and total motility (PM and TM, respectively). After quality control, the final data set consisted of 5,960 records from 949 bulls having semen collected in 10 artificial insemination stations and genotyped at 412,737 SNPs (call rate >95%; minor allele frequency >5%). (Co)variance components were estimated using single trait mixed models, and associations between SNPs and phenotypes were assessed using a genomic BLUP approach. Ten windows that explained the greatest percentage of genetic variance were located on Bos taurus autosomes 1, 2, 4, 6, 7, 23, and 26 for TM and Bos taurus autosomes 1, 2, 4, 6, 8, 16, 23, and 26 for PM. A total of 150 genes for TM and 72 genes for PM were identified within these genomic regions. Gene Ontology enrichment analyses identified significant Gene Ontology terms involved with energy homeostasis, membrane functions, sperm-egg interactions, protection against oxidative stress, olfactory receptors, and immune system. There was significant enrichment of quantitative trait loci for fertility, calving ease, immune response, feed intake, and carcass weight within the candidate windows. These results contribute to understanding the architecture of the genetic control of sperm motility and may aid in the development of strategies to identify subfertile bulls and improve reproductive success.


Asunto(s)
Semen , Motilidad Espermática , Animales , Bovinos/genética , Femenino , Masculino , Genómica , Sitios de Carácter Cuantitativo , Semen/fisiología , Motilidad Espermática/genética , Espermatozoides
2.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493444

RESUMEN

The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νßß) decay. Its main goal is to investigate this decay in ^{130}Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. In this Letter, we present our first results on the search for 0νßß decay of ^{128}Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the ^{128}Te 0νßß decay half-life of T_{1/2}>3.6×10^{24} yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.


Asunto(s)
Granisetrón , Semivida , Teorema de Bayes
3.
Phys Rev Lett ; 129(16): 161805, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36306777

RESUMEN

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3) events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

4.
Eur Phys J C Part Fields ; 82(7): 599, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35821975

RESUMEN

The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and 222 Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background ( ∼ 17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected 222 Rn activity concentration in XENONnT is determined to be 4.2 ( - 0.7 + 0.5 )  µ Bq/kg, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system.

5.
Eur Phys J C Part Fields ; 81(4): 337, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720714

RESUMEN

The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222 Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222 Rn activity concentration of 10 µ Bq / kg in 3.2 t of xenon. The knowledge of the distribution of the 222 Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222 Rn activity concentration in XENON1T. The final 222 Rn activity concentration of ( 4.5 ± 0.1 ) µ Bq / kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.

6.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33750173

RESUMEN

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

7.
Cardiovasc Eng Technol ; 11(5): 532-543, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32748364

RESUMEN

PURPOSE: Computational models of cardiovascular structures rely on their accurate mechanical characterization. A validated method able to infer the material properties of patient-specific large vessels is currently lacking. The aim of the present study is to present a technique starting from the flow-area (QA) method to retrieve basic material properties from magnetic resonance (MR) imaging. METHODS: The proposed method was developed and tested, first, in silico and then in vitro. In silico, fluid-structure interaction (FSI) simulations of flow within a deformable pipe were run with varying elastic modules (E) between 0.5 and 32 MPa. The proposed QA-based formulation was assessed and modified based on the FSI results to retrieve E values. In vitro, a compliant phantom connected to a mock circulatory system was tested within MR scanning. Images of the phantom were acquired and post-processed according to the modified formulation to infer E of the phantom. Results of in vitro imaging assessment were verified against standard tensile test. RESULTS: In silico results from FSI simulations were used to derive the correction factor to the original formulation based on the geometrical and material characteristics. In vitro, the modified QA-based equation estimated an average E = 0.51 MPa, 2% different from the E derived from tensile tests (i.e. E = 0.50 MPa). CONCLUSION: This study presented promising results of an indirect and non-invasive method to establish elastic properties from solely MR images data, suggesting a potential image-based mechanical characterization of large blood vessels.


Asunto(s)
Vasos Sanguíneos/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Modelos Cardiovasculares , Modelación Específica para el Paciente , Módulo de Elasticidad , Humanos , Imagen por Resonancia Magnética/instrumentación , Fantasmas de Imagen , Valor Predictivo de las Pruebas , Impresión Tridimensional , Prueba de Estudio Conceptual , Reproducibilidad de los Resultados , Resistencia a la Tracción
8.
Sci Adv ; 5(9): eaaw3492, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31517044

RESUMEN

European populations display low genetic differentiation as the result of long-term blending of their ancient founding ancestries. However, it is unclear how the combination of ancient ancestries related to early foragers, Neolithic farmers, and Bronze Age nomadic pastoralists can explain the distribution of genetic variation across Europe. Populations in natural crossroads like the Italian peninsula are expected to recapitulate the continental diversity, but have been systematically understudied. Here, we characterize the ancestry profiles of Italian populations using a genome-wide dataset representative of modern and ancient samples from across Italy, Europe, and the rest of the world. Italian genomes capture several ancient signatures, including a non-steppe contribution derived ultimately from the Caucasus. Differences in ancestry composition, as the result of migration and admixture, have generated in Italy the largest degree of population structure detected so far in the continent, as well as shaping the amount of Neanderthal DNA in modern-day populations.


Asunto(s)
ADN Antiguo , Bases de Datos Genéticas , Flujo Genético , Genoma Humano , Población Blanca/genética , Animales , Estudio de Asociación del Genoma Completo , Historia Antigua , Genética Humana , Humanos , Italia , Hombre de Neandertal/genética
9.
Phys Rev Lett ; 122(14): 141301, 2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-31050482

RESUMEN

We report the first experimental results on spin-dependent elastic weakly interacting massive particle (WIMP) nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full ton year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only cases. No significant signal excess is observed, and a profile likelihood ratio analysis is used to set exclusion limits on the WIMP-nucleon interactions. This includes the most stringent constraint to date on the WIMP-neutron cross section, with a minimum of 6.3×10^{-42} cm^{2} at 30 GeV/c^{2} and 90% confidence level. The results are compared with those from collider searches and used to exclude new parameter space in an isoscalar theory with an axial-vector mediator.

10.
Phys Rev Lett ; 122(7): 071301, 2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30848617

RESUMEN

We present first results on the scalar coupling of weakly interacting massive particles (WIMPs) to pions from 1 t yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most nonrelativistic operators, these pion-exchange currents can be coherently enhanced by the total number of nucleons and therefore may dominate in scenarios where spin-independent WIMP-nucleon interactions are suppressed. Moreover, for natural values of the couplings, they dominate over the spin-dependent channel due to their coherence in the nucleus. Using the signal model of this new WIMP-pion channel, no significant excess is found, leading to an upper limit cross section of 6.4×10^{-46} cm^{2} (90% confidence level) at 30 GeV/c^{2} WIMP mass.

11.
Phys Rev Lett ; 123(25): 251801, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31922764

RESUMEN

We report constraints on light dark matter (DM) models using ionization signals in the XENON1T experiment. We mitigate backgrounds with strong event selections, rather than requiring a scintillation signal, leaving an effective exposure of (22±3) tonne day. Above ∼0.4 keV_{ee}, we observe <1 event/(tonne day keV_{ee}), which is more than 1000 times lower than in similar searches with other detectors. Despite observing a higher rate at lower energies, no DM or CEvNS detection may be claimed because we cannot model all of our backgrounds. We thus exclude new regions in the parameter spaces for DM-nucleus scattering for DM masses m_{χ} within 3-6 GeV/c^{2}, DM-electron scattering for m_{χ}>30 MeV/c^{2}, and absorption of dark photons and axionlike particles for m_{χ} within 0.186-1 keV/c^{2}.

12.
Phys Rev Lett ; 123(24): 241803, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31922867

RESUMEN

Direct dark matter detection experiments based on a liquid xenon target are leading the search for dark matter particles with masses above ∼5 GeV/c^{2}, but have limited sensitivity to lighter masses because of the small momentum transfer in dark matter-nucleus elastic scattering. However, there is an irreducible contribution from inelastic processes accompanying the elastic scattering, which leads to the excitation and ionization of the recoiling atom (the Migdal effect) or the emission of a bremsstrahlung photon. In this Letter, we report on a probe of low-mass dark matter with masses down to about 85 MeV/c^{2} by looking for electronic recoils induced by the Migdal effect and bremsstrahlung using data from the XENON1T experiment. Besides the approach of detecting both scintillation and ionization signals, we exploit an approach that uses ionization signals only, which allows for a lower detection threshold. This analysis significantly enhances the sensitivity of XENON1T to light dark matter previously beyond its reach.

13.
Phys Rev Lett ; 121(11): 111302, 2018 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-30265108

RESUMEN

We report on a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS. XENON1T utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30±0.01) ton, resulting in a 1.0 ton yr exposure. The energy region of interest, [1.4,10.6] keV_{ee} ([4.9,40.9] keV_{nr}), exhibits an ultralow electron recoil background rate of [82_{-3}^{+5}(syst)±3(stat)] events/(ton yr keV_{ee}). No significant excess over background is found, and a profile likelihood analysis parametrized in spatial and energy dimensions excludes new parameter space for the WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c^{2}, with a minimum of 4.1×10^{-47} cm^{2} at 30 GeV/c^{2} and a 90% confidence level.

14.
Artículo en Inglés | MEDLINE | ID: mdl-29521567

RESUMEN

The principal aim of this study was to monitor the occurrence of some metals and polycyclic aromatic hydrocarbons (PAHs) in fish and mussels from the Gulf of Naples. A comparison with previous researches of the same area was carried out, and the intakes of these compounds through the diet and their effect on the tolerable intake values (when available) were assessed. Cadmium (Cd), chromium (Cr), and lead (Pb) were detected by flameless atomic absorption spectroscopy (Cd, Cr, and Pb); arsenic (As) and mercury (Hg) were detected by applying the hydride method. PAHs were detected by high-performance liquid chromatography. Widespread contamination was found. Among the metals, Hg showed the highest maximum levels of 284.94 ng/g wet weight (ww) in fish and 480.00 ng/g ww in mussels. Chrysene, phenanthrene, fluoranthene, anthracene, and benzo[k]fluoranthene were the most common PAHs in fish, whereas benzo[a]anthracene, pyrene, phenanthrene, acenaphthylene, and acenaphthene were the most frequently occurring compounds in mussels. The concentrations of As, Cr, Hg, Pb, and PAHs in fish were found to decrease over a period of 30 years, whereas the Cd levels remained constant. The Hg, Pb, and PAH levels in mussels increased over the period 2010 to 2016. Finally, the average consumption of mussels led to the highest effect on the Tolerable Daily Intake of Hg, which was exceeded by 19%.


Asunto(s)
Arsénico/análisis , Monitoreo del Ambiente , Actividades Humanas , Metales/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Alimentos Marinos/análisis , Animales , Bivalvos/química , Cadmio/análisis , Cromo/análisis , Monitoreo del Ambiente/métodos , Productos Pesqueros/análisis , Peces , Humanos , Italia , Plomo/análisis , Mercurio/análisis , Contaminantes Químicos del Agua/análisis
15.
Int J Surg Case Rep ; 42: 154-157, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29274599

RESUMEN

INTRODUCTION: The obturator hernia is a rare pelvic hernia that often comes in the shape of bowel obstruction caused by the presence of an intestinal segment, more often ileum, passing trough the obturator foramen of the pelvic wall (Fig. 1). This type of hernia accounts for 0.5-1.4% of all hernias. CASE PRESENTATION: We report the clinical case of a 84-year-old woman with no previous surgical interventions, who went to the emergency room complaining of vomit and nausea, bowels closed to gas and stool, which she had experienced for three previous days. Routine blood test showed impaired renal function and hydrohelectrolyte imbalance. A CT scan revealed a right ileal, strangulated obturator hernia. The patient underwent an emergency surgical intervention with laparoscopic trans-abdominal peritoneal approach (TAP): after the reduction of the herniated segment, a primary suturing of the parietal defect was performed without ileal resection. DISCUSSION: Because of the non-specific symptoms the diagnosis of this kind of hernia is often unclear; female are 6-9 times more likely than men to be subject to the aforementioned pathology, mostly occurring in multiparous, emaciated, elderly woman so it is also called "the little old lady's hernia". Risk factors are loss of weight, chronic pulmonary disease and ascites which increase the abdominal pressure. An unfrequent presenting sign is a palpable mass, or the Howship-Romberg sign- a pain radiating from the inner tigh and knee - but it could be misleading when confused with symptoms of gonarthrosis or lumbar vertebral disc pathology. CT scan has superior sensitivity and accuracy with respect to other radiological exams to assess the presence of an obturator hernia. CONCLUSION: Obturator hernia is a rare type of hernia due to his diagnosis, which is often unclear; a prompt suspect based for the non-specific symptoms is crucial for the diagnosis. Surgical management depends on early diagnosis and it is the only possible treatment for this pathology.

19.
Biofabrication ; 8(3): 035001, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27431399

RESUMEN

Spinal fusion is the gold standard surgical procedure for degenerative spinal conditions when conservative therapies have been unsuccessful in rehabilitation of patients. Novel strategies are required to improve biocompatibility and osseointegration of traditionally used materials for lumbar cages. Furthermore, new design and technologies are needed to bridge the gap due to the shortage of optimal implant sizes to fill the intervertebral disc defect. Within this context, additive manufacturing technology presents an excellent opportunity to fabricate ergonomic shape medical implants. The goal of this study is to design and manufacture a 3D-printed lumbar cage for lumbar interbody fusion. Optimisations of the proposed implant design and its printing parameters were achieved via in silico analysis. The final construct was characterised via scanning electron microscopy, contact angle, x-ray micro computed tomography (µCT), atomic force microscopy, and compressive test. Preliminary in vitro cell culture tests such as morphological assessment and metabolic activities were performed to access biocompatibility of 3D-printed constructs. Results of in silico analysis provided a useful platform to test preliminary cage design and to find an optimal value of filling density for 3D printing process. Surface characterisation confirmed a uniform coating of nHAp with nanoscale topography. Mechanical evaluation showed mechanical properties of final cage design similar to that of trabecular bone. Preliminary cell culture results showed promising results in terms of cell growth and activity confirming biocompatibility of constructs. Thus for the first time, design optimisation based on computational and experimental analysis combined with the 3D-printing technique for intervertebral fusion cage has been reported in a single study. 3D-printing is a promising technique for medical applications and this study paves the way for future development of customised implants in spinal surgical applications.


Asunto(s)
Materiales Biocompatibles , Impresión Tridimensional , Prótesis e Implantes , Fusión Vertebral/instrumentación , Estrés Mecánico , Tejido Adiposo/citología , Fuerza Compresiva , Simulación por Computador , Humanos , Microscopía de Fuerza Atómica , Modelos Biológicos , Células Madre/fisiología
20.
Eur J Appl Physiol ; 116(7): 1395-410, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27225620

RESUMEN

PURPOSE: We analyzed the best performance times of master cycling athletes in the 200-3000 m track competitions to estimate the decay of maximal aerobic power (MAP) and anaerobic capacity (AnS) with aging. METHODS: In various decades of age (30-80 years), MAP and AnS were estimated using an iterative procedure as the values that minimize the difference between: (1) the metabolic power ([Formula: see text]) necessary to cover a given distance (d) in the time t and; (2) the maximal metabolic power ([Formula: see text]) maintained at a constant level throughout the competition. RESULTS: MAP started decreasing at 45 years of age. Thereafter, it showed an average percent rate of decrease of about 16 % for decade, as previously shown in other classes of master athletes. In addition, AnS seemed to decay by about 11 % every 10 years from the second part of the fifth decade. CONCLUSIONS: The decay of MAP occurred in spite of the active lifestyle of the subjects and it may be attributed to the progressive impairment of maximal O2 delivery and/or of peripheral O2 utilization. The loss of AnS might derive from the progressive loss of muscle mass occurring after the fifth decade of life, to the progressive qualitative deterioration of the anaerobic energy yielding pathways or to the lower capacity of MN recruitment during maximal efforts. The proposed approach may be applied to other types of human locomotion of whom the relationship between performance t and [Formula: see text] is known.


Asunto(s)
Envejecimiento/fisiología , Umbral Anaerobio/fisiología , Rendimiento Atlético/fisiología , Ciclismo/fisiología , Tolerancia al Ejercicio/fisiología , Modelos Biológicos , Adulto , Anciano , Anciano de 80 o más Años , Anaerobiosis/fisiología , Simulación por Computador , Ejercicio Físico/fisiología , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología
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