29 research outputs found
Multiple Use SiPM Integrated Circuit (MUSIC) for Large Area and High Performance Sensors
The 8-channel Multiple Use Silicon Photo-multiplier (SiPM) Integrated Circuit (MUSIC) Application specific integrated circuit (ASIC) for SiPM anode readout has been designed for applications where large photo-detection areas are required. MUSIC offers three main features: (1) Sum of the eight input channels using a differential output driver, (2) eight individual single ended (SE) analog outputs, and (3) eight individual SE binary outputs using a time over threshold technique. Each functionality, summation and individual readout includes a selectable dual-gain configuration. Moreover, the signal sum implements a dual-gain output providing a 15-bit dynamic range. The circuit contains a tunable pole zero cancellation of the SiPM recovery time constant to deal with most of the available SiPM devices in the market. Experimental tests show how MUSIC can linearly sum signals from different SiPMs and distinguish even a few photons. Additionally, it provides a single photon output pulse width at half maximum (FWHM) between 5-10 ns for the analog output and a single-photon time resolution (SPTR) around 118 ps sigma using a Hamamatsu SiPM S13360-3075CS for the binary output. Lastly, the summation mode has a power consumption of approximate to 200 mW, whereas the individual readout consumes approximate to 30 mW/ch
MATRIX16: A 16-Channel Low-Power TDC ASIC with 8 ps Time Resolution
This paper presents a highly configurable 16-channel TDC ASIC designed in a commercial 180 nm technology with the following features: time-of-flight and time-over-threshold measurements, 8.6 ps LSB, 7.7 ps jitter, 5.6 ps linearity error, up to 5 MHz of sustained input rate per channel, 9.1 mW of power consumption per channel, and an area of 4.57 mm2 . The main contributions of this work are the novel design of the clock interpolation circuitry based on a resistive interpolation mesh circuit and the capability to operate at different supply voltages and operating frequencies, thus providing a compromise between TDC resolution and power consumption. Keywords: TDC; time-to-digital converter; fast timing; PET; VLSI; ASIC; ToF; ToT; low power; frontend electronic
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2,MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA,the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions ofthe SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE.This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV.PostprintPeer reviewe
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V
On the biodegradability, mechanical behavior, and cytocompatibility of amorphous Mg72Zn23Ca5and crystalline Mg70Zn23Ca5Pd2alloys as temporary implant materials
The evolution of microstructure and mechanical properties of almost fully amorphous Mg72Zn23Ca5 and crystalline Mg70Zn23Ca5Pd2 alloys during immersion in Hank's balanced salt solution (HBSS), as well as their cytocompatibility, are investigated in order to assess the feasibility of both materials as biodegradable implants. Though the crystalline Mg70Zn23Ca5Pd2 sample shows lower wettability and more positive corrosion potential, this sample degrades much faster upon incubation in HBSS as a consequence of the formation of micro-galvanic couples between the nobler Pd-rich dendrites and the surrounding phases. After 22-h immersion, the concentration of Mg ions in the HBSS medium containing the Mg70Zn23Ca5Pd2 sample is six times larger than for Mg72Zn23Ca5. Due to the Zn enrichment and the incipient porosity, the mechanical properties of the Mg72Zn23Ca5 sample improve within the first stages of biodegradation (i.e., hardness increases while the Young's modulus decreases, thus rendering an enhanced wear resistance). Cytocompatibility studies reveal that neither Mg72Zn23Ca5 nor Mg70Zn23Ca5Pd2 are cytotoxic, although preosteoblast cell adhesion is to some extent precluded, particularly onto the surface of Mg70Zn23Ca5Pd2, because of the relatively high hydrophobicity. Because of their outstanding properties and their time-evolution, the use of the Pd-free alloy in temporary implants such as screws, stents, and sutures is envisioned
Improved mechanical performance and delayed corrosion phenomena in biodegradable Mg–Zn–Ca alloys through Pd-alloying
The influence of partial substitution of Mg by Pd on the microstructure, mechanical properties and corrosion behaviour of Mg72−xZn23Ca5Pdx (x=0, 2 and 6 at.%) alloys, synthesized by copper mould casting, is investigated. While the Mg72Zn23Ca5 alloy is mainly amorphous, the addition of Pd decreases the glass-forming ability, thus favouring the formation of crystalline phases. From a mechanical viewpoint, the hardness increases with the addition of Pd, from 2.71 GPa for x=0 to 3.9 GPa for x=6, mainly due to the formation of high-strength phases. In turn, the wear resistance is maximized for an intermediate Pd content (i.e., Mg70Zn23Ca5Pd2). Corrosion tests in a simulated body fluid (Hank’s solution) indicate that Pd causes a shift in the corrosion potential towards more positive values, thus delaying the biodegradability of this alloy. Moreover, since the cytotoxic studies with mouse preosteoblasts do not show dead cells after culturing for 27 h, these alloys are potential candidates to be used as biomaterials
Desigualdade temporal de intervalos RR como um novo indicador psicofisiológico de estresse mental
Introduction: Gini coefficient (Gini index or Gini ratio) is a parameter that is normally used in economy to measure the income distribution in a country or in the whole wide world, but it can be used to measure any kind of distribution.
In the present study it is exposed an innovative proposal of application of the Gini coefficient to Heart Rate Variability (HRV) like a psychophysiological indicator of mental stress.
Purpose: To assess the application of the Gini coefficient as a psychophysiological indicator of mental stress.
Methods: The involved participants are 13 healthy individuals (age 19 ± 1.5 years). Heart rate was continuously recorded at rest (5 minutes) and during a mental stress (5 minutes). Linear and nonlinear methods of heart rate variability were assessed, and 2 new indicators (Sequential and Non-Sequential Gini) were calculated and proposed to measure HRV differences between states.
Results: When comparing rest and mental stress conditions, a sensible decrease of the traditional indicators of the HRV was founded (p<0.05), an increase of the heart rate (p=0.004) and of the Sequential Gini (p=0.004) and Non-Sequential Gini (p=0.04).
Conclusions: The results suggest that temporary inequality of the RR intervals analyzed from the Gini coefficient could be an adequate indicator of sympathetic activity present during the mental stress, with great potentialities with the objective to assess the consequences of psychosomatic affections and anxiety disorders.Introducción: El coeficiente de Gini o índice de Gini es un parámetro que normalmente se usa en economía para medir la distribución del ingreso en un país o en todo el mundo, pero puede usarse para medir cualquier tipo de distribución. En el presente estudio se expone una propuesta innovadora de aplicación del coeficiente de Gini a la Variabilidad de la Frecuencia Cardíaca (VFC) como indicador psicofisiológico del estrés mental.
Objetivo: Evaluar la aplicación del coeficiente de Gini como indicador psicofisiológico de estrés mental.
Métodos: Los participantes involucrados son 13 individuos sanos (edad 19 ± 1,5 años). La frecuencia cardíaca se registró continuamente en reposo (5 minutos) y durante un estrés mental (5 minutos). Se evaluaron métodos lineales y no lineales de variabilidad de la frecuencia cardíaca, y se calcularon y propusieron 2 nuevos indicadores (Gini secuencial y no secuencial) para medir las diferencias de VFC entre estados.
Resultados: Al comparar las condiciones de reposo y estrés mental, se encontró una sensible disminución de los indicadores tradicionales de la VFC (p<0,05), un aumento de la frecuencia cardiaca (p=0,004) y del Gini Secuencial (p=0,004) y Gini no secuencial (p=0,04).
Conclusiones: Los resultados sugieren que la desigualdad temporal de los intervalos RR analizados a partir del coeficiente de Gini podría ser un indicador adecuado de la actividad simpática presente durante el estrés mental, con grandes potencialidades en la evaluación las consecuencias de afecciones psicosomáticas y trastornos de ansiedad.Introdução: O coeficiente de Gini ou índice de Gini é um parâmetro normalmente usado em economia para medir a distribuição de renda em um país ou no mundo, mas pode ser usado para medir qualquer tipo de distribuição. No presente estudo, apresenta-se uma proposta inovadora de aplicação do coeficiente de Gini à Variabilidade da Frequência Cardíaca (VFC) como indicador psicofisiológico de estresse mental.Objetivo: Avaliar a aplicação do coeficiente de Gini como indicador psicofisiológico de estresse mental.Métodos: Os participantes envolvidos são 13 indivíduos saudáveis (idade 19 ± 1,5 anos). A frequência cardíaca foi registrada continuamente em repouso (5 minutos) e durante o estresse mental (5 minutos). Métodos lineares e não lineares de variabilidade da frequência cardíaca foram avaliados e 2 novos indicadores (gini sequencial e não sequencial) foram calculados e propostos para medir as diferenças na VFC entre os estados.Resultados: Ao comparar as condições de repouso e estresse mental, foi encontrada diminuição significativa nos indicadores tradicionais da VFC (p<0,05), aumento da frequência cardíaca (p=0,004) e do Gini Sequencial (p= 0,004) e não - Gini sequencial (p=0,04).Conclusões: Os resultados sugerem que a desigualdade temporal dos intervalos RR analisados a partir do coeficiente de Gini pode ser um indicador adequado da atividade simpática presente durante o estresse mental, com grande potencial na avaliação das consequências de condições psicossomáticas e transtornos de ansiedade
Desigualdad temporal de los intervalos RR como un nuevo indicador psicofisiológico de estrés mental
Introduction: Gini coefficient (Gini index or Gini ratio) is a parameter that is normally used in economy to measure the income distribution in a country or in the whole wide world, but it can be used to measure any kind of distribution. In the present study it is exposed an innovative proposal of application of the Gini coefficient to Heart Rate Variability (HRV) like a psychophysiological indicator of mental stress.Objective: To assess the application of the Gini coefficient as a psychophysiological indicator of mental stress.Methods: A non-observational crossover study, carried out in the biomedical laboratory of the Medical University of Santiago de Cuba. The involved participants are 13 healthy individuals (age 19 ± 1.5 years). Heart rate was continuously recorded at rest (5 minutes) and during a mental stress (5 minutes). Linear and nonlinear methods of heart rate variability were assessed, and 2 new indicators (Sequential and Non-Sequential Gini) were calculated and proposed to measure HRV differences between states.Results: When comparing rest and mental stress conditions, a sensible decrease of the traditional indicators of the HRV was founded (p<0,05), an increase of the heart rate (p=0,004) and of the Sequential Gini (p=0,004) and Non-Sequential Gini (p=0,04).Conclusions: The results suggest that temporary inequality of the RR intervals analyzed from the Gini coefficient could be an adequate indicator of sympathetic activity present during the mental stress.Introducción: El coeficiente de Gini o índice de Gini es un parámetro que normalmente se usa en economía para medir la distribución del ingreso en un país o en todo el mundo, pero puede usarse para medir cualquier tipo de distribución. En el presente estudio se expone una propuesta innovadora de aplicación del coeficiente de Gini a la Variabilidad de la Frecuencia Cardíaca (VFC) como indicador psicofisiológico del estrés mental.Objetivo: Evaluar la aplicación del coeficiente de Gini como indicador psicofisiológico de estrés mental.Métodos: Estudio no observacional de corte transversal, llevado a cabo en el laboratorio de estudios biomédicos de la Universidad Médica de Santiago Cuba. Los participantes involucrados fueron 13 individuos sanos (edad 19 ± 1,5 años). La frecuencia cardíaca se registró continuamente en reposo (5 minutos) y durante un estrés mental (5 minutos). Se evaluaron métodos lineales y no lineales de variabilidad de la frecuencia cardíaca, y se calcularon y propusieron 2 nuevos indicadores (Gini secuencial y no secuencial) para medir las diferencias de VFC entre estados.Resultados: Al comparar las condiciones de reposo y estrés mental, se encontró una sensible disminución de los indicadores tradicionales de la VFC (p<0,05), un aumento de la frecuencia cardiaca (p=0,004) y del Gini Secuencial (p=0,004) y Gini no secuencial (p=0,04).Conclusiones: Los resultados sugieren que la desigualdad temporal de los intervalos RR analizados a partir del coeficiente de Gini podría ser un indicador adecuado de la actividad simpática presente durante el estrés mental