687 research outputs found
Reproductive biology of Chlaenius velutinus (Duftschmid, 1812)(Coleoptera, Carabidae) in the south of the Iberian Peninsula
Se estudia la biología de reproducción de Chlaenius velutinus Duftschmid, 1812, especie bien representada en las comunidades de carábidos ripícolas del sur de la Península, en las que suele ser un elemento dominante. Se parte de muestreos sistemáticos efectuados en el arroyo Arenosillo (tributario de la cuenca del Guadalquivir por su margen derecho), de estudios anatómicos relativos a la edad y sexo de los ejemplares y al estado gonadal de las hembras y de cultivos de laboratorio. Los resultados indican que la actividad de los imagos se centra en primavera, con un máximo en abril y mayo, momento en que también es máxima la oviposición, que la fecundidad es elevada (10,05 huevos/hembra), que el período medio de desarrollo en el laboratorio es algo más de un mes y que la fase más crítica, en condiciones artificiales, es la eclosión del huevo. De todo lo anterior se deduce que el ciclo de vida de C. velutinus se ajusta al de los reproductores de primavera (Larsson, 1939)
On the uniqueness of -gonal automorphisms of Riemann surfaces
Let be a compact Riemann surface of genus . A cyclic subgroup of
prime order of is called properly -gonal if it has a fixed
point and the quotient surface has genus . We show that if , then a
properly -gonal subgroup of is unique. We also discuss some
related results.Comment: final version, 9 pages, minor improvements, added 2 reference
Low-Cost Prototype to Automate the 3D Digitization of Pieces: An Application Example and Comparison
This work is aimed at describing the design of a mechanical and programmable 3D capturing system to be used by either 3D scanner or DSLR camera through photogrammetry. Both methods are widely used in diverse areas, from engineering, architecture or archaeology, up to the field of medicine; but they also entail certain disadvantages, such as the high costs of certain equipment, such as scanners with some precision, and the need to resort to specialized operatives, among others. The purpose of this design is to create a robust, precise and cost-effective system that improves the limitations of the present equipment on the market, such as robotic arms or rotary tables. For this reason, a preliminary study has been conducted to analyse the needs of improvement, later, we have focused on the 3D design and prototyping. For its construction, there have been used the FDM additive technology and structural components that are easy to find in the market. With regards to electronic components, basic electronics and Arduino-based 3D printers firmware have been selected. For system testing, the capture equipment consists of a Spider Artec 3D Scanner and a Nikon 5100 SLR Camera. Finally, 3D models have been developed by comparing the 3D meshes obtained by the two methods, obtaining satisfactory results
PCV147 Impact Of Heart Failure On Hospital Admissions And Mortality In Spain In The Period 2009-2013
Inverse Low Gain Avalanche Detectors (iLGADs) for precise tracking and timing applications
Low Gain Avalanche Detector (LGAD) is the baseline sensing technology of the
recently proposed Minimum Ionizing Particle (MIP) end-cap timing detectors
(MTD) at the Atlas and CMS experiments. The current MTD sensor is designed as a
multi-pad matrix detector delivering a poor position resolution, due to the
relatively large pad area, around 1 ; and a good timing resolution,
around 20-30 ps. Besides, in his current technological incarnation, the timing
resolution of the MTD LGAD sensors is severely degraded once the MIP particle
hits the inter-pad region since the signal amplification is missing for this
region. This limitation is named as the LGAD fill-factor problem. To overcome
the fill factor problem and the poor position resolution of the MTD LGAD
sensors, a p-in-p LGAD (iLGAD) was introduced. Contrary to the conventional
LGAD, the iLGAD has a non-segmented deep p-well (the multiplication layer).
Therefore, iLGADs should ideally present a constant gain value over all the
sensitive region of the device without gain drops between the signal collecting
electrodes; in other words, iLGADs should have a 100 fill-factor by
design. In this paper, tracking and timing performance of the first iLGAD
prototypes is presented.Comment: Conference Proceedings of VCI2019, 15th Vienna Conference of
Instrumentation, February 18-22, 2019, Vienna, Austri
The Star Formation History of M32
We use deep HST ACS/HRC observations of a field within M32 (F1) and an M31
background field (F2) to determine the star formation history (SFH) of M32 from
its resolved stellar population. We find that 2-5Gyr old stars contribute
\som40%+/- 17% of M32's mass, while 55%+/-21% of M32's mass comes from stars
older than 5 Gyr. The mass-weighted mean age and metallicity of M32 at F1 are
=6.8+/-1.5 Gyr and =-0.01+/-0.08 dex. The SFH additionally
indicates the presence of young (<2 Gyr old), metal-poor ([M/H]\sim-0.7) stars,
suggesting that blue straggler stars contribute ~2% of the mass at F1; the
remaining \sim3% of the mass is in young metal-rich stars. Line-strength
indices computed from the SFH imply a light-weighted mean age and metallicity
of 4.9 Gyr and [M/H] = -0.12 dex, and single-stellar-population-equivalent
parameters of 2.9+/-0.2 Gyr and [M/H]=0.02+/-0.01 dex at F1 (~2.7 re). This
contradicts spectroscopic studies that show a steep age gradient from M32's
center to 1re. The inferred SFH of the M31 background field F2 reveals that the
majority of its stars are old, with \sim95% of its mass already acquired 5-14
Gyr ago. It is composed of two dominant populations; \sim30%+/-7.5% of its mass
is in a 5-8 Gyr old population, and \sim65%+/-9% of the mass is in a 8-14 Gyr
old population. The mass-weighted mean age and metallicity of F2 are
=9.2+/-1.2 Gyr and =-0.10+/-0.10 dex, respectively. Our results
suggest that the inner disk and spheroid populations of M31 are
indistinguishable from those of the outer disk and spheroid. Assuming the mean
age of M31's disk at F2 (\sim1 disk scale length) to be 5-9 Gyr, our results
agree with an inside-out disk formation scenario for M31's disk.Comment: Accepted to ApJ. 24 pages, 18 figures. A high-resolution version can
be downloaded from http://www.astro.rug.nl/~monachesi/monachesi-sfh.pd
Determinación del estado hídrico en viña a través de imágenes RGB y multiespectrales adquiridas por un VANT
La teledetección se ha convertido en una herramienta muy utilizada en la agricultura de precisión. La existencia de sensores ligeros, calibrados geométrica y radiométricamente, ha hecho que los vehículos aéreos no tripulados (VANTs) sean una de las plataformas más utilizadas en teledetección por obtener datos de muy alta resolución espacial y temporal. En el marco de la viticultura de precisión, haciendo uso de VANTs para la obtención de imágenes aéreas de la cubierta vegetal que proporcionen
información agronómicamente útil para hacer un manejo y una gestión del riego sostenible y eficiente frente a la escasez hídrica existente principalmente en zonas áridas y semiáridas, se llevó a cabo un estudio en un viñedo localizado en Fuente-Álamo (Albacete) durante 2018 y 2019. Para obtener un amplio rango de condiciones de estado hídrico de la vid, varias estrategias de riego fueron aplicadas incluyendo regímenes con diferentes niveles de salinidad del agua, estableciendo diferencias en el estado hídrico de la cepa. Los vuelos se hicieron a lo largo del ciclo fenológico usando sensores convencionales (o RGB -red, green, blue-) y multiespectrales a bordo de un VANT, obteniendo ortoimágenes. Estas ortoimágenes fueron segmentadas para incluir solo la vegetación obteniendo el grado de cobertura verde como un parámetro geométrico representativo del desarrollo vegetal del cultivo. El potencial hídrico de tallo fue medido a mediodía con cámaras de presión, y la integral de estrés hídrico fue calculada a partir de estas medidas de estado hídrico, como una variable representativa del efecto acumulado de la intensidad y duración del estrés hídrico desde el comienzo del ciclo de desarrollo hasta el momento de la medida. Modelos de regresión lineal simple usando índices de vegetación basados en la respuesta espectral de la vegetación y el grado de cobertura verde fueron evaluados para predecir la integral de estrés hídrico. Técnicas de regresión no lineal usando redes neuronales artificiales con bandas de los sensores multiespectral y RGB y el grado de cobertura verde como variables predictoras de la integral de estrés hídrico también fueron empleadas. Ambos modelos mostraron que los datos del rango visible (pese a la menor reflectividad de la vegetación en este rango espectral) fueron más útiles para predecir la integral de estrés hídrico que los datos del rango multiespectral, que consideran la reflectividad en el red-edge y en el infrarrojo cercano, proporcionando mejores resultados los modelos no lineales de redes neuronales artificiales con valores de R2 próximos a 1 y errores relativos de 1.5 %
o ligeramente superiores. La mayor resolución espacial, calidad radiométrica, facilidad de uso de la cámara RGB, su menor precio y fácil procesamiento de las imágenes RGB hace que estos sensores, utilizados en menor medida con usos agrícolas, sean una buena opción para usarse en la predicción del estado hídrico en viña
Accuracy and Survival Outcomes after National Implementation of Sentinel Lymph Node Biopsy in Early Stage Endometrial Cancer
Altres ajuts: acords transformatius de la UABSentinel lymph node (SLN) biopsy has recently been accepted to evaluate nodal status in endometrial cancer at early stage, which is key to tailoring adjuvant treatments. Our aim was to evaluate the national implementation of SLN biopsy in terms of accuracy to detect nodal disease in a clinical setting and oncologic outcomes according to the volume of nodal disease. A total of 29 Spanish centers participated in this retrospective, multicenter registry including patients with endometrial adenocarcinoma at preoperative early stage who had undergone SLN biopsy between 2015 and 2021. Each center collected data regarding demographic, clinical, histologic, therapeutic, and survival characteristics. A total of 892 patients were enrolled. After the surgery, 12.9% were suprastaged to FIGO 2009 stages III-IV and 108 patients (12.1%) had nodal involvement: 54.6% macrometastasis, 22.2% micrometastases, and 23.1% isolated tumor cells (ITC). Sensitivity of SLN biopsy was 93.7% and false negative rate was 6.2%. After a median follow up of 1.81 years, overall surivial and disease-free survival were significantly lower in patients who had macrometastases when compared with patients with negative nodes, micrometastases or ITC. In our nationwide cohort we obtained high sensitivity of SLN biopsy to detect nodal disease. The oncologic outcomes of patients with negative nodes and low-volume disease were similar after tailoring adjuvant treatments. In total, 22% of patients with macrometastasis and 50% of patients with micrometastasis were at low risk of nodal metastasis according to their preoperative risk factors, revealing the importance of SLN biopsy in the surgical management of patients with early stage EC
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