Structural investigation of MOVPE-Grown GaAs on Ge by X-ray techniques

The selection of appropriate characterisation methodologies is vital for analysing and comprehending the sources of defects and their influence on the properties of heteroepitaxially grown III-V layers. In this work we investigate the structural properties of GaAs layers grown by Metal-Organic Vapour Phase Epitaxy (MOVPE) on Ge substrates – (100) with 6⁰ offset towards – under various growth conditions. Synchrotron X-ray topography (SXRT) is employed to investigate the nature of extended linear defects formed in GaAs epilayers. Other X-ray techniques, such as reciprocal space mapping (RSM) and triple axis ω-scans of (00l)-reflections (l = 2, 4, 6) are used to quantify the degree of relaxation and presence of antiphase domains (APDs) in the GaAs crystals. The surface roughness is found to be closely related to the size of APDs formed at the GaAs/Ge heterointerface, as confirmed by X-ray diffraction (XRD), as well as atomic force microscopy (AFM), and transmission electron microscopy (TEM)

Structural investigation of MOVPE-Grown GaAs on Ge by X-ray techniques

The selection of appropriate characterisation methodologies is vital for analysing and comprehending the sources of defects and their influence on the properties of heteroepitaxially grown III-V layers. In this work we investigate the structural properties of GaAs layers grown by Metal-Organic Vapour Phase Epitaxy (MOVPE) on Ge substrates – (100) with 6⁰ offset towards – under various growth conditions. Synchrotron X-ray topography (SXRT) is employed to investigate the nature of extended linear defects formed in GaAs epilayers. Other X-ray techniques, such as reciprocal space mapping (RSM) and triple axis ω-scans of (00l)-reflections (l = 2, 4, 6) are used to quantify the degree of relaxation and presence of antiphase domains (APDs) in the GaAs crystals. The surface roughness is found to be closely related to the size of APDs formed at the GaAs/Ge heterointerface, as confirmed by X-ray diffraction (XRD), as well as atomic force microscopy (AFM), and transmission electron microscopy (TEM)

Frequency-Dependent Squeezing for Advanced LIGO

The first detection of gravitational waves by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 launched the era of gravitational wave astronomy. The quest for gravitational wave signals from objects that are fainter or farther away impels technological advances to realize ever more sensitive detectors. Since 2019, one advanced technique, the injection of squeezed states of light is being used to improve the shot noise limit to the sensitivity of the Advanced LIGO detectors, at frequencies above $\sim 50$ Hz. Below this frequency, quantum back action, in the form of radiation pressure induced motion of the mirrors, degrades the sensitivity. To simultaneously reduce shot noise at high frequencies and quantum radiation pressure noise at low frequencies requires a quantum noise filter cavity with low optical losses to rotate the squeezed quadrature as a function of frequency. We report on the observation of frequency-dependent squeezed quadrature rotation with rotation frequency of 30Hz, using a 16m long filter cavity. A novel control scheme is developed for this frequency-dependent squeezed vacuum source, and the results presented here demonstrate that a low-loss filter cavity can achieve the squeezed quadrature rotation necessary for the next planned upgrade to Advanced LIGO, known as "A+."Comment: 6 pages, 2 figures, to be published in Phys. Rev. Let

Have historical land use/land cover changes triggered a fire regime shift in central Spain?

Fire is one of the main disturbance factors shaping the landscape, and landscape is a key driver of fire behavior. Considering the role played by land use and land cover (LULC) changes as the main driver of landscape dynamics, the aim of this study was to calculate and analyze (i) the real impact of fire on LULC changes and (ii) how these LULC changes were influencing the fire regime. We used methods of historical geography and socio-spatial systemic analysis for reconstructing and assessing the LULC change and fire history in six case studies in the Central Mountain System (Spain) from archival documentary sources and historical cartography. The main result is an accurate dataset of fire records from 1497 to 2013 and a set of LULC maps for three time points (1890s–1930s, 1956–1957, and the 2000s). We have shown the nonlinear evolution of the fire regime and the importance of the local scale when assessing the interaction of landscape dynamics and fire regime variation. Our findings suggest that LULC trends have been the main influencing factor of fire regime variation in Central Spain since the mid-19th centuryinfo:eu-repo/semantics/publishedVersio

Headache during pregnancy : an observational study

Introducción: Las cefaleas primarias (CP) tienen mayor prevalencia e incidencia a menor edad y en su mayoría afectan a mujeres. La predilección femenina puede ser explicada por la relación de la cefalea y las hormonas sexuales, en particular el estrógeno. La migraña es la CP más discapacitante. Diversos estudios demuestran que dicha cefalea mejora durante el embarazo, principalmente en cuanto a frecuencia e intensidad. Objetivo: Caracterizar las CP según su intensidad y frecuencia durante el embarazo, además de valorar aspectos demográficos y clínicos asociados en estas pacientes. Materiales y métodos: Estudio descriptivo, transversal que analizó al azar mujeres durante el embarazo o puerperio mediato y se investigó el padecimiento de cefalea antes o durante el curso de dicho estado, mediante un cuestionario realizado por médicos del Servicio de Neurología. Se emplearon criterios de la International Headache Society 2018 (IHS) para la clasificación de cefaleas. Se analizaron datos con EpiInfo 7. Resultados: Se incluyeron 102 pacientes obstétricas. La media de edad fue de 27,6 años (DS+/-7). El 47,1% cursaba puerperio, 40,2% tercer trimestre, 7,8% segundo trimestre, 4,9% primer trimestre. El 14% presentaba antecedentes patológicos previos. El 89,2% padecía CP previa al embarazo siendo mayor en frecuencia la cefalea tensional episódica (61,8%). Se observó que hubo mejoría durante el embarazo en el 71,4%.Además se vio que el 12,8% de las pacientes presentaron cefalea nueva durante el embarazo siendo más frecuente la secundaria (8,8%). Conclusión: Entre las pacientes que presentaban CP previa al embarazo se observó que la mayoría mejoró durante el mismo. Además se concluyó que ante la aparición de cefalea nueva durante el embarazo se deberían realizar estudios complementarios ya que la mayoría fue secundaria a patologías graves.Introduction: Primary headache disorders (PH) are pathologies with high prevalence and incidence in young people, affecting women predominantly. Female predilection is associated with the linkage between headache and sexual hormones, mainly estrogens. Migraine is the most disabling primary headache. Some studies have shown that intensity and frequency of migraine tend to improve during pregnancy. Objetive: Describe primary headaches during pregnancy, in terms of frequency and intensity, and assess demographic and clinical manifestations associated with this condition. Subjects and methods: Descriptive, transversal study that randomly analyzed women during pregnancy or mediate puerperium. Existence of headache before and after these conditions was investigated trough a questionary made by physicians of the Neurology Service. International Headache Society 2018 criteria (IHS) were used to classify headaches. Data were analyzed with EpiInfo 7. Results: One hundred and twoobstetric patients were included. Median agewas 27,6 (SD +/-7). 47,1% patientswere in puerperium, 40,2% in the third trimester, 7.8% in the second trimester and 4.9% in the first trimester. Previous medical history was reported in 14% cases. PH prior to pregnancy was reported in 89.2% patients, being episodic tension headache the most frequent (61.8%). Improvement of headache during pregnancy was detected in 71.4% of the cases. There was a 12,8% of new-onset headache during pregnancy, with the secondary etiology as the most frequent cause (8,8%). Conclusion: Most of the headaches previous to pregnancy improve during this condition. New-onset headache during pregnancy must induce to request complementary studies in order to rule out severe secondary etiologies.Fil: Peñalver, F.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Galiana, G.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Delfino, C.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Farfan Alé, F.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Sánchez, C.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Gonzalez, M.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Giner, F.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Rodríguez, N.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Martínez, M.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y NeurocirugíaFil: Ianardi, S.. Hospital Luis Lagomaggiore (Mendoza, Argentina). Servicio de Neurología y Neurocirugí

Body weight satisfaction and antifat attitudes

Nature of the Proceeding: Appeal Trial Court and Judge: Appeal from the Third District Court, Salt Lake County, Judge John Paul Kenned

Nanoscale electrical characterization of arrowhead defects in GalnP thin films grown on Ge

In this work the authors present an electrical characterization of the so called arrowhead defects (ADs) in GaInP thin films grown on Ge(100) substrates misoriented by 6° toward (111). The samples have been evaluated by means of conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). It is shown that the ADs have terminating planes which are composed from two alternating subplanes inclined 12° (close to {105} plane) and 6° (close to {109}) with respect to the (100) plane. The terminating planes of the arrowhead defects possess higher conductivity compared to their surrounding. The terminating planes differ also in their electrical behavior from each other, demonstrating different values of conductivity (C-AFM) and bucking voltages (KPFM). The difference in current densities between two terminating planes was found to be ∼ 170±35 μA/m2 at −3 V, and the difference in the bucking voltages was ∼ 70 mV at 5 V of the electrical excitation signal in the lift mode. It is suggested that the distinctive electrical behavior of the ADs is caused by an ordering effect which leads in this case to the degraded electrical properties of the ADs