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2.
Nature ; 555(7695): 190-196, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29466337

RESUMEN

From around 2750 to 2500 bc, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 bc. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain's gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries.


Asunto(s)
Evolución Cultural/historia , Genoma Humano/genética , Genómica , Migración Humana/historia , Cromosomas Humanos Y/genética , ADN Antiguo , Europa (Continente) , Pool de Genes , Genética de Población , Haplotipos , Historia Antigua , Humanos , Masculino , Análisis Espacio-Temporal
3.
Odontology ; 112(1): 112-124, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37074599

RESUMEN

To investigate the effect of ELVAX polymer subgingival implants incorporated with echistatin peptide on incisor reimplanted tooth in rats. Forty-two male Wistars rats were divided into two groups: echistatin-treated rats (E) and control rats (C). The animals had their right maxillary incisors extracted and treated according to the International Association of Dental Traumatology replantation protocol. The extra-alveolar dry period was 30 and 60 min, and the post-surgical experimental periods were 15, 60, and 90 days. The samples were stained with H&E and analyzed for the presence of an inflammatory response, incidence of resorptions, and dental ankylosis. Results were statistically analyzed (p < 0.05). The presence of inflammatory resorption was significantly higher in group C at 30 and 60 min extra-alveolar time, in the 15-day postoperative period as compared with the E group (p < 0.05). Dental ankylosis was significantly more prevalent in group E in 30 min extra-alveolar time and 15 days postoperative period (p < 0.05). However, in 60 min extra-alveolar time and 60 days postoperative period, dental ankylosis was more prevalent in C group (p < 0.05). The use of ELVAX subgingival implants with echistatin demonstrated therapeutic potential in preventing the experimental resorption process after replantation of maxillary incisors in rats.


Asunto(s)
Implantes Dentales , Resorción Radicular , Anquilosis del Diente , Ratas , Masculino , Animales , Ratas Wistar , Anquilosis del Diente/prevención & control , Polímeros , Reimplante Dental/métodos
4.
Sensors (Basel) ; 24(1)2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38202998

RESUMEN

This work involves exploring non-invasive sensor technologies for data collection and preprocessing, specifically focusing on novel thermal calibration methods and assessing low-cost infrared radiation sensors for facial temperature analysis. Additionally, it investigates innovative approaches to analyzing acoustic signals for quantifying coughing episodes. The research integrates diverse data capture technologies to analyze them collectively, considering their temporal evolution and physical attributes, aiming to extract statistically significant relationships among various variables for valuable insights. The study delineates two distinct aspects: cough detection employing a microphone and a neural network, and thermal sensors employing a calibration curve to refine their output values, reducing errors within a specified temperature range. Regarding control units, the initial implementation with an ESP32 transitioned to a Raspberry Pi model 3B+ due to neural network integration issues. A comprehensive testing is conducted for both fever and cough detection, ensuring robustness and accuracy in each scenario. The subsequent work involves practical experimentation and interoperability tests, validating the proof of concept for each system component. Furthermore, this work assesses the technical specifications of the prototype developed in the preceding tasks. Real-time testing is performed for each symptom to evaluate the system's effectiveness. This research contributes to the advancement of non-invasive sensor technologies, with implications for healthcare applications such as remote health monitoring and early disease detection.


Asunto(s)
Inteligencia Artificial , Redes Neurales de la Computación , Humanos , Pruebas en el Punto de Atención , Acústica , Tos
5.
Opt Express ; 30(9): 15546-15555, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35473271

RESUMEN

Recent studies in high-order harmonic generation (HHG) in solid targets reveal new scenarios of extraordinary rich electronic dynamics, in comparison to the atomic and molecular cases. For the later, the main aspects of the process can be described semiclassically in terms of electrons that recombine when the trajectories revisit the parent ion. HHG in solids has been described by an analogous mechanism, in this case involving electron-hole pair recombinations. However, it has been recently reported that a substantial part of the HHG emission corresponds to situations where the electron and hole trajectories do not overlap in space. According to the present knowledge, HHG from this imperfect recollisions reflects the quantum nature of the process, arising in systems with large Berry curvatures or for elliptically polarized driving fields. In this work, we demonstrate that imperfect recollisions are also relevant in the more general case. We show the signature of such recollisions in the HHG spectrum from monolayer graphene -a system with null Berry curvature- irradiated by linearly polarized driving fields. Our calculations also reveal that imperfect multiple-order recollisions contribute to the harmonic emission when electron-hole excursion times exceed one cycle of the driving field. We believe that our work adds a substantial contribution to the full understanding of the sub-femtosecond dynamics of HHG in solid systems.

6.
Ecotoxicology ; 31(9): 1462-1476, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36319920

RESUMEN

Information regarding the safety and environmental risks of pesticides intended for urban use remains limited. This study aimed to assess the effects of four common pesticides on the microalga Raphidocelis subcapitata: DIAZINON® 25% C. E., Roundup®, URBACIN® 20C. E., and VAPODEL® 20% C. E., which are commercial formulations of diazinon, glyphosate, dichlorvos, and cypermethrin, respectively. According to 96-h inhibition of population growth bioassays, the four pesticide toxicities exemplified the following order: DIAZINON® (diazinon) > Roundup® (glyphosate) > VAPODEL® (dichlorvos) > URBACIN® (cypermethrin). Increasing pesticide concentrations elicited alterations in the specific growth rates (µmax). The macromolecule contents and photosynthetic pigments increased in groups exposed to the highest concentrations of DIAZINON® 25%, Roundup®, and URBACIN® 20 compared to the control group, despite these treatments inducing lower population growth rates. VAPODEL® 20% induced higher growth rates and lower macromolecule content compared to the control. Since active ingredients were not quantified, certain comparisons may prove limiting, but it is important to assess the effects of the whole mixtures in the form that they enter the environment, especially for urban-intended applications or generic formulations with higher additive contents. Finally, this study demonstrated that commercial pesticide formulations designed for urban applications might pose a threat to freshwater microalgae due to their underestimated toxic potential, but further studies are required.


Asunto(s)
Chlorophyceae , Plaguicidas , Plaguicidas/toxicidad , Diazinón/toxicidad , Diclorvos/farmacología , Crecimiento Demográfico
7.
J Couns Psychol ; 69(6): 775-785, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36048046

RESUMEN

The present study sought to apply an intersectional lens in predicting decent work (i.e., work that meets minimum standards for supporting worker dignity and livelihood). With a racially diverse sample of 302 women workers, we tested a moderated mediation model predicting decent work from economic constraints, experiences of sexism, experiences of racism, and the interaction of racism and sexism. Following psychology of working theory (PWT), we positioned work volition and career adaptability as mediators. Main effects were consistent with previous PWT theory and research, indicating that experiences of sexism and racism were important direct and indirect predictors of decent work. Interaction effects indicated that the interaction of sexism and racism predicted work volition and that the indirect effect of sexism on decent work was stronger at higher levels of racism. Results have implications for policymakers and practitioners seeking to support women across racial backgrounds in securing decent work. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Ocupaciones , Racismo , Humanos , Femenino , Teoría Psicológica , Grupos Raciales , Sexismo , Volición
8.
Opt Express ; 29(2): 2488-2500, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726443

RESUMEN

The efficiency of high-harmonic generation (HHG) from a macroscopic sample is strongly linked to the proper phase matching of the contributions from the microscopic emitters. We develop a combined micro+macroscopic theoretical model that allows us to distinguish the relevance of high-order harmonic phase matching in single-layer graphene. For a Gaussian driving beam, our simulations show that the relevant HHG emission is spatially constrained to a phase-matched ring around the beam axis. This remarkable finding is a direct consequence of the non-perturbative behavior of HHG in graphene-whose harmonic efficiency scaling is similar to that already observed in gases- and bridges the gap between the microscopic and macroscopic HHG in single-layer graphene.

9.
J Clin Periodontol ; 48(7): 896-906, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33745150

RESUMEN

AIM: To identify loci associated with stages III/IV, grade C periodontitis (PIII/IV-C) through a genome-wide association study (GWAS). MATERIALS AND METHODS: 441 Caucasian Spanish PIII/IV-C cases from the SEPA Network of Research Clinics and 1141 controls from the Banco Nacional de ADN were genotyped with "Axiom Spain Biobank Array," which contains 757836 markers, including rare and low-frequency Spanish variants. The analysis of the individual association and subsequently the gene-level analysis with Sequence Kernel Association Test (SKAT) were carried out adjusting for age, sex and PC1 covariates. Pathway Analysis was additionally performed with Ingenuity Pathway Analysis (IPA) software on the top associated genes. RESULTS: In the individual analyses, no genome-wide significant signals were detected. However, 8 SNPs of 8 loci reached suggestive evidence of association with PIII/IV-C, including FAT3 rs35709256, CSNK1G2 rs4807188, MYH13 rs2074872, CNTN2 rs116611488, ANTXR1 rs4854545, 8p23.2 rs78672540, ANGPT1 rs13439823 and PLEC rs11993287 (p < 5 × 10-6 ). SKAT analysis identified other interesting signals at CNTN2, FBXO44, AP1M2, RSPO4, KRI1, BPIFB1 and INMT, although their probability does not exceed the multiple-test correction. IPA indicated significant enrichment of pathways related to cAMP, IL-2, CD28, VDR/RXR and PI3K/Akt.  CONCLUSIONS: GWAS found no SNPs significantly associated with PIII/IV-C.


Asunto(s)
Periodontitis Agresiva , Estudio de Asociación del Genoma Completo , Periodontitis Agresiva/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , España
10.
J Mater Sci Mater Med ; 32(12): 150, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34874480

RESUMEN

OBJECTIVES: The objective of the present work was to evaluate the ultrasonic agitation, time and vehicle (propylene glycol or distilled water) on the antimicrobial potential and penetrability of calcium hydroxide pastes on infected dentin by means of Confocal Laser Scanning Microscopy (CLSM) and microbiological culture (MC). MATERIALS AND METHODS: Dentin specimens were infected with Enterococcus faecalis using a new contamination protocol of 5 days. The specimens were divided into eight groups and dressed with the pastes for 7 or 15 days: G1) calcium hydroxide (CH) + propylene glycol (prop)/7 days (d), G2) CH + prop/7d + ultrasonic agitation (U), G3) CH + distilled water (dw)/7d, G4) CH + dw/7d + U, G5) CH + prop/15d, G6) CH + prop/15d + U, G7) CH + dw/15d, G8) CH + dw/15d + U. The ultrasonic activation was made for 1 min in both directions with a plain point insert. After medications removal, the images obtained by CLSM showed the viable (green) and dead (red) bacteria with Live and Dead dye. By the MC, the dentinal wall debris obtained by burs were collected for colony counts. For the penetration test, the Rodamine B dye was added to the CH pastes and analyzed by CLSM. RESULTS: The 7 and 15-days CH + prop+U pastes performed better antimicrobial efficacy, followed by the CH + dw+U/15d paste. CONCLUSIONS: All pastes demonstrated better penetration and antimicrobial activity against E. faecalis when agitated with ultrasound, even in periods of up to seven days. The propylene glycol vehicle showed better results. CLINICAL RELEVANCE: Agitation of the dressing that remains for less time inside the root canal can optimize the decontamination of endodontic treatment.


Asunto(s)
Hidróxido de Calcio/farmacología , Diente , Terapia por Ultrasonido/efectos adversos , Animales , Antiinfecciosos/farmacología , Hidróxido de Calcio/farmacocinética , Bovinos , Cementos Dentales/farmacocinética , Cementos Dentales/farmacología , Cavidad Pulpar/efectos de los fármacos , Cavidad Pulpar/microbiología , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Materiales de Obturación del Conducto Radicular/farmacocinética , Materiales de Obturación del Conducto Radicular/farmacología , Irrigantes del Conducto Radicular/farmacocinética , Factores de Tiempo , Diente/efectos de los fármacos , Diente/metabolismo , Diente/microbiología , Permeabilidad Dental/efectos de los fármacos , Ultrasonido/métodos
11.
Sensors (Basel) ; 21(15)2021 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-34372261

RESUMEN

Saccadic electrooculograms are discrete biosignals that contain the instantaneous angular position of the human eyes as a response to saccadic visual stimuli. These signals are essential to monitor and evaluate several neurological diseases, such as Spinocerebellar Ataxia type 2 (SCA2). For this, biomarkers such as peak velocity, latency and duration are computed. To compute these biomarkers, we need to obtain the velocity profile of the signals using numerical differentiation methods. These methods are affected by the noise present in the electrooculograms, specially in subjects that suffer neurological diseases. This noise complicates the comparison of the differentiation methods using real saccadic signals because of the impossibility of establishing exact saccadic onset and offset points. In this work, we evaluate 16 differentiation methods by the design of an experiment that uses synthetic saccadic electrooculograms generated from parametric models of both healthy subjects and subjects suffering from Spinocerebellar Ataxia type 2 (SCA2). For these synthetic electrooculograms the exact velocity profile is known, hence we can use them as a reference for comparison and error computing for the tasks of saccade identification and saccade biomarker computing. Finally, we identify the best fitting method or methods for each evaluated task.


Asunto(s)
Movimientos Sacádicos , Electrooculografía , Humanos
12.
Molecules ; 26(16)2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34443621

RESUMEN

There are few novel therapeutic options available for companion animals, and medications rely heavily on repurposed drugs developed for other species. Considering the diversity of species and breeds in companion animal medicine, comprehensive PK exposures in the companion animal patient is often lacking. The purpose of this paper was to assess the pharmacokinetics after oral and intravenous dosing in domesticated animal species (dogs, cats, and horses) of a novel soluble epoxide hydrolase inhibitor, EC1728, being developed for the treatment of pain in animals. Results: Intravenous and oral administration revealed that bioavailability was similar for dogs, and horses (42 and 50% F) but lower in mice and cats (34 and 8%, respectively). Additionally, clearance was similar between cats and mice, but >2× faster in cats vs. dogs and horses. Efficacy with EC1728 has been demonstrated in mice, dogs, and horses, and despite the rapid clearance of EC1728 in cats, analgesic efficacy was demonstrated in an acute pain model after intravenous but not oral dosing. Conclusion: These results demonstrate that exposures across species can vary, and investigation of therapeutic exposures in target species is needed to provide adequate care that addresses efficacy and avoids toxicity.


Asunto(s)
Desarrollo de Medicamentos , Inhibidores Enzimáticos/metabolismo , Epóxido Hidrolasas/antagonistas & inhibidores , Animales , Disponibilidad Biológica , Gatos , Perros , Inhibidores Enzimáticos/farmacocinética , Inhibidores Enzimáticos/farmacología , Epóxido Hidrolasas/química , Caballos , Ratones , Solubilidad , Especificidad de la Especie
13.
Actas Esp Psiquiatr ; 49(4): 145-154, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34195970

RESUMEN

Research evidence points to a critical period of about five years after the first psychotic episode, being its resolution of utmost importance for the chronicity of the disorder. In addition, several studies suggest the high correlation between adult psychosis and childhood adversity, and a dose-response relationship in severity level.


Asunto(s)
Experiencias Adversas de la Infancia , Trastornos Psicóticos , Adulto , Niño , Humanos
14.
BMC Bioinformatics ; 21(Suppl 2): 85, 2020 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-32164553

RESUMEN

BACKGROUND: In the field of protein engineering and biotechnology, the discovery and characterization of structural patterns is highly relevant as these patterns can give fundamental insights into protein-ligand interaction and protein function. This paper presents GSP4PDB, a bioinformatics web tool that enables the user to visualize, search and explore protein-ligand structural patterns within the entire Protein Data Bank. RESULTS: We introduce the notion of graph-based structural pattern (GSP) as an abstract model for representing protein-ligand interactions. A GSP is a graph where the nodes represent entities of the protein-ligand complex (amino acids and ligands) and the edges represent structural relationships (e.g. distances ligand - amino acid). The novel feature of GSP4PDB is a simple and intuitive graphical interface where the user can "draw" a GSP and execute its search in a relational database containing the structural data of each PDB entry. The results of the search are displayed using the same graph-based representation of the pattern. The user can further explore and analyse the results using a wide range of filters, or download their related information for external post-processing and analysis. CONCLUSIONS: GSP4PDB is a user-friendly and efficient application to search and discover new patterns of protein-ligand interaction.


Asunto(s)
Ligandos , Proteínas/metabolismo , Interfaz Usuario-Computador , Animales , Bases de Datos de Proteínas , Humanos , Enlace de Hidrógeno , Mapas de Interacción de Proteínas , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas/química , Dedos de Zinc
15.
Bioconjug Chem ; 31(12): 2737-2749, 2020 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-33232126

RESUMEN

Objective: Random formation of thrombi is classified as a pathological process that may result in partial or complete obstruction of blood flow and limited perfusion. Further complications include pulmonary embolism, thrombosis-induced myocardial infraction, ischemic stroke, and others. Location and full delineation of the blood clot are considered to be two clinically relevant aspects that could streamline proper diagnosis and treatment follow-up. In this work, we prepared two types of X-ray attenuating contrast formulations, using fibrinogen aptamer as the clot-seeking moiety. Methods: Two novel aptamer-targeted formulations were designed. Iodine-modified bases were directly incorporated into a fibrinogen aptamer (iodo-FA). Isothermal titration calorimetry was used to confirm that these modifications did not negatively impact target binding. Iodo-FA was tested for its ability to produce concentration-dependent contrast enhancement in a phantom CT. It was subsequently tested in vitro with clotted human and swine blood. This allowed for translation into ex vivo testing, using fluoroscopy. FA was also used to functionalize gold nanoparticles (FA-AuNPs), and contrast capabilities were confirmed. This formulation was tested in vitro using clotted human blood in a CT scan. Results: Unmodified FA and iodo-FA demonstrated a nearly identical affinity toward fibrin, confirming that base modifications did not impact target binding. Iodo-FA and FA-AuNPs both demonstrated excellent concentration-dependent contrast enhancement capabilities (40.5 HU mM-1 and 563.6 HU µM-1, respectively), which were superior to the clinically available agent, iopamidol. In vitro CT testing revealed that iodo-FA is able to penetrate into the blood clots, producing contrast enhancement throughout, while FA-AuNPs only accumulated on the surface of the clot. Iodo-FA was thereby translated to ex vivo testing, confirming target-binding associated accumulation of the contrast material at the location of the clot within the dilation of the external carotid artery. This resulted in a 34% enhancement of the clot. Conclusions: Both iodo-FA and FA-AuNPs were confirmed to be effective contrast formulations in CT. Targeting of fibrin, a major structural constituent of thrombi, with these novel contrast agents would allow for higher contrast enhancement and better clot delineation in CT and fluoroscopy.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Medios de Contraste/metabolismo , Fluoroscopía/métodos , Trombosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Animales , Humanos , Porcinos
16.
Ann Surg Oncol ; 27(5): 1329-1337, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32112212

RESUMEN

This first part of a two-part review of pheochromocytoma and paragangliomas (PPGLs) addresses clinical presentation, diagnosis, management, treatment, and outcomes. In this first part, the epidemiology, prevalence, genetic etiology, clinical presentation, and biochemical and radiologic workup are discussed. In particular, recent advances in the genetics underlying PPGLs and the recommendation for genetic testing of all patients with PPGL are emphasized. Finally, the newer imaging methods for evaluating of PPGLs are discussed and highlighted.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico , Paraganglioma Extraadrenal/diagnóstico , Feocromocitoma/diagnóstico , Abdomen , Neoplasias de las Glándulas Suprarrenales/epidemiología , Neoplasias de las Glándulas Suprarrenales/genética , Neoplasias de las Glándulas Suprarrenales/fisiopatología , Arritmias Cardíacas/fisiopatología , Catecolaminas/sangre , Catecolaminas/orina , Células Cromafines/metabolismo , Ganglios Parasimpáticos , Ganglios Simpáticos , Pruebas Genéticas , Cefalea/fisiopatología , Humanos , Hipertensión/fisiopatología , Neoplasia Endocrina Múltiple Tipo 2a/diagnóstico , Neoplasia Endocrina Múltiple Tipo 2a/genética , Neoplasia Endocrina Múltiple Tipo 2b/diagnóstico , Neoplasia Endocrina Múltiple Tipo 2b/genética , Síndromes Neoplásicos Hereditarios/diagnóstico , Síndromes Neoplásicos Hereditarios/genética , Neurofibromatosis 1/diagnóstico , Neurofibromatosis 1/genética , Paraganglioma/diagnóstico , Paraganglioma/epidemiología , Paraganglioma/genética , Paraganglioma/fisiopatología , Paraganglioma Extraadrenal/epidemiología , Paraganglioma Extraadrenal/genética , Paraganglioma Extraadrenal/metabolismo , Pelvis , Feocromocitoma/epidemiología , Feocromocitoma/genética , Feocromocitoma/fisiopatología , Sudoración/fisiología , Enfermedad de von Hippel-Lindau/diagnóstico , Enfermedad de von Hippel-Lindau/genética
17.
Ann Surg Oncol ; 27(5): 1338-1347, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32112213

RESUMEN

This is the second part of a two-part review on pheochromocytoma and paragangliomas (PPGLs). In this part, perioperative management, including preoperative preparation, intraoperative, and postoperative interventions are reviewed. Current data on outcomes following resection are presented, including outcomes after cortical-sparing adrenalectomy for bilateral adrenal disease. In addition, pathological features of malignancy, surveillance considerations, and the management of advanced disease are also discussed.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/cirugía , Hipertensión/tratamiento farmacológico , Hipoglucemia/terapia , Hipotensión/terapia , Paraganglioma Extraadrenal/cirugía , Atención Perioperativa/métodos , Feocromocitoma/cirugía , Complicaciones Posoperatorias/terapia , Neoplasias de las Glándulas Suprarrenales/complicaciones , Adrenalectomía/métodos , Antagonistas Adrenérgicos alfa/uso terapéutico , Antagonistas Adrenérgicos beta/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Fluidoterapia , Humanos , Hiperinsulinismo/diagnóstico , Hiperinsulinismo/epidemiología , Hiperinsulinismo/terapia , Hipertensión/etiología , Hipoglucemia/diagnóstico , Hipoglucemia/epidemiología , Hipotensión/diagnóstico , Hipotensión/epidemiología , Laparoscopía , Neoplasia Endocrina Múltiple Tipo 2a , Neoplasia Endocrina Múltiple Tipo 2b , Recurrencia Local de Neoplasia/epidemiología , Paraganglioma/complicaciones , Paraganglioma/cirugía , Paraganglioma Extraadrenal/complicaciones , Feocromocitoma/complicaciones , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Procedimientos Quirúrgicos Robotizados , Resultado del Tratamiento , Tirosina 3-Monooxigenasa/antagonistas & inhibidores , Vasoconstrictores/uso terapéutico , Enfermedad de von Hippel-Lindau
18.
Opt Express ; 28(13): 19760-19771, 2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32672246

RESUMEN

We study high-order harmonic generation (HHG) in armchair-type single-wall carbon nanotubes (SWNTs) driven by ultrashort, mid-infrared laser pulses. For a SWNT with chiral indices (n, n), we demonstrate that HHG is dominated by bands |m| = n - 1 and that the cut-off frequency saturates with intensity, as it occurs in the case of single layer graphene. As a consequence, HHG in SWNTs can be described effectively as a one-dimensional periodic system, whose high-frequency emission can be modified through the proper control of the structural parameters. Additionally, we show that the HHG mechanism in nanotubes has some similarities to that previously reported in single layer graphene. However, as a main difference, the electron-hole pair excitation in SWNTs is connected to the non-adiabatic crossing through the first van Hove singularity of the |m| = n - 1 bands, instead of the crossing through the Dirac point that takes place in graphene.

19.
Glob Chang Biol ; 26(4): 2505-2518, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31860143

RESUMEN

The role of future forests in global biogeochemical cycles will depend on how different tree species respond to climate. Interpreting the response of forest growth to climate change requires an understanding of the temporal and spatial patterns of seasonal climatic influences on the growth of common tree species. We constructed a new network of 310 tree-ring width chronologies from three common tree species (Quercus robur, Pinus sylvestris and Fagus sylvatica) collected for different ecological, management and climate purposes in the south Baltic Sea region at the border of three bioclimatic zones (temperate continental, oceanic, southern boreal). The major climate factors (temperature, precipitation, drought) affecting tree growth at monthly and seasonal scales were identified. Our analysis documents that 20th century Scots pine and deciduous species growth is generally controlled by different climate parameters, and that summer moisture availability is increasingly important for the growth of deciduous species examined. We report changes in the influence of winter climate variables over the last decades, where a decreasing influence of late winter temperature on deciduous tree growth and an increasing influence of winter temperature on Scots pine growth was found. By comparing climate-growth responses for the 1943-1972 and 1973-2002 periods and characterizing site-level growth response stability, a descriptive application of spatial segregation analysis distinguished sites with stable responses to dominant climate parameters (northeast of the study region), and sites that collectively showed unstable responses to winter climate (southeast of the study region). The findings presented here highlight the temporally unstable and nonuniform responses of tree growth to climate variability, and that there are geographical coherent regions where these changes are similar. Considering continued climate change in the future, our results provide important regional perspectives on recent broad-scale climate-growth relationships for trees across the temperate to boreal forest transition around the south Baltic Sea.

20.
Phys Rev Lett ; 125(14): 141104, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33064506

RESUMEN

The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources.

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