High spatial resolution monolithic pixel detector in SOI technology Bugiel, R.; Bugiel, S.; Dannheim, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2021, Letnik:
988
Journal Article
Recenzirano
Odprti dostop
This paper presents test-beam results of monolithic pixel detector prototypes fabricated in 200 nm Silicon-On-Insulator (SOI) CMOS technology studied in the context of high spatial resolution ...performance. The tested detectors were fabricated on a 500 μm thick high-resistivity Floating Zone type n (FZ-n) wafer and on a 300 μm Double SOI Czochralski type p (DSOI Cz-p) wafer. The pixel size is 30 μm×30 μm and two different front-end electronics architectures were tested, a source follower and a charge-sensitive preamplifier. The test-beam data analyses were focused mainly on determination of the spatial resolution and the hit detection efficiency. In this work different cluster formation and position reconstruction methods are studied. In particular, a generalization of the standard η-correction adapted for arbitrary cluster sizes, is introduced. The obtained results give in the best case a spatial resolution of about 1.5 μm for the FZ-n wafer and about 3.0 μm for the DSOI Cz-p wafer, both detectors showing detection efficiency above 99.5%.
Furan is a naturally forming compound found in heat-processed foods such as coffee, canned meats, and jarred baby food. It is concurrently found with analogues including 2-methylfuran (2-MF) and ...3-methylfuran (3-MF), and toxicity studies demonstrate all are potent liver toxins. Toxicity studies found 3-MF is more toxic than either furan, or 2-MF. The present analysis assesses the transcriptional response in liver samples taken from male Fischer (F344) rats exposed to furan or 3-MF from 0 to 2.0 and 0–1.0 mg/kg bw/day, respectively, for 90 days. Transcriptional analyses found decreased liver function and fatty acid metabolism are common responses to both furan and 3-MF exposure. Furan liver injury promotes a ductular reaction through Hippo and TGFB signalling, which combined with increased immune response results in ameliorating perturbed bile acid homeostasis in treated rats. Failure to activate these pathways in 3-MF exposed rats and decreased p53 activity leads to cholestasis, and increased toxicity. Finally, BMD analysis indicate many of the most sensitive pathways affected by furan and 3-MF exposure relate to metabolism - malate dehydrogenase and glucose metabolism with BMDLs of 0.03 and 0.01 mg/kg bw/day for furan and 3-MF exposure, respectively, which agrees with BMDLs previously reported for apical and microarray data.
•Both furan and 3-MF exposure decrease liver function and fatty acid metabolism.•Furan liver injury promotes a ductular reaction through Hippo and TGFB signalling.•Ductular reaction with an immune response betters perturbed bile acid homeostasis.•Inactivation of these pathways and p53 with 3-MF exposure leads to cholestasis.•BMD analysis indicates the most sensitive pathways affected relate to metabolism.
Ochratoxin A (OTA) is a mycotoxin produced by species of Penicillium and Aspergillus, and is found in many commodities including cereal grains, nuts, and coffee. OTA is a renal carcinogen and ...nephrotoxin at high concentrations, targeting the proximal tubules. This study uses transcriptomics and the previously reported apical data (Bondy et al., 2021) to infer mode-of-action of OTA toxicity in male and female rats exposed to low doses of OTA in utero and throughout development. Our findings support a male-specific activation of the innate and adaptive immune responses in F1 pups to OTA exposure. This was not found in the female F1 pups, and may be due to female-specific increased p38 activity and VDR signaling. Differentially expressed genes related to karyomegaly, MAPK activity, and immune activation appears to develop from in utero exposure to OTA whereas those related to decreased kidney and liver function, and changes to reproductive pathways occur in both rat generations. Together, these transcriptional results confirm that dietary exposure to OTA causes renal toxicity as well as alterations to hepatic and reproductive pathways in rats. In utero exposure of rats to OTA results in sex-specific alterations in immune response pathways, VDR signaling, and p38 activity.
•OTA exposure in utero results in activation of the immune response in male rats.•Altered kidney, liver, and reproductive pathways occur in both sexes of F0 and F1 rats.•Differences in karyomegaly, MAPK activity, and immune activation develop from in utero OTA exposure.•Active immune response in male rats and MAPK signaling in female rats contribute to the sex-specific OTA-induced toxicities.
Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium molds. Grain-based foods account for most human dietary exposures to OTA. OTA is a teratogen, but its reproductive and ...developmental effects are poorly understood. A one-generation reproductive toxicity study was conducted with groups of 16 male and 16 female Fischer rats exposed to 0, 0.026, 0.064, 0.16, 0.4 or 1.0 mg OTA/kg in diet. Dams exposed to 1.0 mg OTA/kg diet had statistically significant F1 pup losses between implantation and postnatal day (PND 4). Delays in preputial separation (PPS) and vaginal opening (VO) were indicative of delayed puberty in F1 rats. Mild renal lesions in nursing pups indicated that exposure prior to weaning impacted the kidneys. The developing kidney was more susceptible to OTA than the adult kidney. Significant increases in multi-oocyte follicles (MOFs) and proportional changes in resting and growing follicles were observed in F1 female ovaries. Plasma testosterone was reduced in F0 males, and there were negative effects on sperm quality in F0 and F1 male rats. The results confirm that continuous dietary exposure to OTA causes post-implantation fetotoxicity in dams, and renal and reproductive toxicity in their male and female offspring.
•Gestational exposure to OTA caused pre-implantation fetotoxicity in female rats.•Dietary exposure to OTA adversely affected sperm motility in adult male rats.•OTA delayed puberty in juvenile male and female rats.•Developmental OTA exposure A adversely affected ovarian follicle populations.•OTA caused kidney toxicity in nursing and weaned juvenile rats.
This paper details initial results from a study of electrical effects resulting from hypervelocity impacts at a Van de Graaff dust accelerator. Iron particles between 10−15 g and 10−10 g in mass were ...impacted on several different metallic targets at speeds of 1 km/s to 50 km/s. The goal of this study is to characterize the impact-generated plasma and associated RF emission. Results are presented from data collected using retarding potential analyzers. The rate of signal detection was found to have a dependence both on material and on target bias. From a single analyzer, some signal waveforms exhibited oscillatory behavior which is significant in determining the effect of impacts on spacecraft. Using two analyzers at different distances from the target, the expansion speed of the impact plasma was measured to be between 10 km/s and 30 km/s.
► We ran a hypervelocity impact experiment using a Van de Graaff dust accelerator. ► Plasma measurements from impacts of iron on tungsten and aluminum are presented. ► Dependence of plasma generation on target material and electrical bias was studied. ► Oscillatory plasma measurements are compared to potential mechanisms. ► Average measured plasma expansion speed is 20.8 km/s.
The design and measurement results of an ultra-low power multi-channel fast 10-bit Analog-to-Digital Converter (ADC) ASIC, developed for readout systems in future particle physics experiments, are ...discussed. An 8-channel prototype with a PLL-based data serialization and a fast data transmission was designed and fabricated in a 130 nm CMOS process. The ADC converts analog data with sampling rates from about 10 kS/s to 40 MS/s, with power consumption proportional to sampling rate. The resulting Figure of Merit (FOM), for sampling rates 5-40 MS/s, is 35-42 fJ/conv.-step, per ADC channel. Similar power contribution is spent for fast data serialization and the largest contribution goes to data transmission. A wide spectrum of static and dynamic measurements confirm very good performance of this multi-channel ADC with ENOB ~9.2 bits, an excellent channel uniformity, and negligible crosstalk. The ADC works asynchronously and so it is not limited to systems with uniform time sampling. The ADC is designed using dynamic circuitry which eliminates static power consumption (except leakage), as a consequence it is ready for applications requiring power cycling.
Signal coupling to embedded pitch adapters in silicon sensors Artuso, M.; Betancourt, C.; Bezshyiko, I. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2018, Letnik:
877
Journal Article
Recenzirano
Odprti dostop
We have examined the effects of embedded pitch adapters on signal formation in n-substrate silicon microstrip sensors with data from beam tests and simulation. According to simulation, the presence ...of the pitch adapter metal layer changes the electric field inside the sensor, resulting in slowed signal formation on the nearby strips and a pick-up effect on the pitch adapter. This can result in an inefficiency to detect particles passing through the pitch adapter region. All these effects have been observed in the beam test data.
To understand the process of cosmic dust particle impacts and translate crater morphology on smoothed metallic surfaces to dust properties, correct calibration of the experimental impact data is ...needed. This article presents the results of studies of crater morphology generated by impacts using micron‐sized polypyrrole (PPy)‐coated olivine particles. The particles were accelerated by an electrostatic dust accelerator to high speeds before they impacted onto polished aluminum targets. The projectile diameter and velocity ranges were 0.3–1.2 μm and 3–7 km s−1. After impact, stereopair images of the craters were taken using scanning electron microscope and 3‐D reconstructions made to provide diameter and depth measurements. In this study, not just the dimensions of crater diameters and depths, but also the shape and dimensions of crater lips were analyzed. The craters created by the coated olivine projectiles are shown to have complicated shapes believed to be due to the nonspherical shape of the projectiles.
The interplanetary space probe Cassini/Huygens reached Saturn in July 2004 after 7 years of cruise phase. The German cosmic dust analyser (CDA) was developed under the leadership of the Max Planck ...Institute for Nuclear Physics in Heidelberg under the support of the DLR e.V. This instrument measures the interplanetary, interstellar and planetary dust in our solar system since 1999 and provided unique discoveries. In 1999, CDA detected interstellar dust in the inner solar system followed by the detection of electrical charges of interplanetary dust grains during the cruise phase between Earth and Jupiter. The instrument determined the composition of interplanetary dust and the nanometre-sized dust streams originating from Jupiter’s moon Io. During the approach to Saturn in 2004, similar streams of submicron grains with speeds in the order of 100 km/s were detected from Saturn’s inner and outer ring system and are released to the interplanetary magnetic field. Since 2004 CDA measured more than one million dust impacts characterising the dust environment of Saturn. The instrument is one of the three experiments which discovered the active ice geysers located at the south pole of Saturn’s moon Enceladus in 2005. Later, a detailed compositional analysis of the water ice grains in Saturn’s E ring system led to the discovery of large reservoirs of liquid water (oceans) below the icy crust of Enceladus. Finally, the determination of the dust-magnetosphere interaction and the discovery of the extended E ring (at least twice as large as predicted) allowed the definition of a dynamical dust model of Saturn’s E ring describing the observed properties. This paper summarizes the discoveries of a 10-year story of success based on reliable measurements with the most advanced dust detector flown in space until today. This paper focuses on cruise results and findings achieved at Saturn with a focus on flux and density measurements. CDA discoveries related to the detailed dust stream dynamics, E ring dynamics, its vertical profile and E ring compositional analysis are published elsewhere (see Hus et al. in AIP Conference Proccedings 1216:510–513,
2010
; Hsu et al. in Icarus 206:653–661,
2010
; Kempf et al. in Icarus 193:420,
2008
; 206(2):446,
2010
; Postberg et al. in Icarus 193(2):438,
2008
; Nature 459:1098,
2009
; Nature,
2011
, doi:
10.1038/nature10175
).
The NASA Stardust mission used silica aerogel slabs to slowly decelerate and capture impinging cosmic dust particles for return to Earth. During this process, impact tracks are generated along the ...trajectory of the particle into the aerogel. It is believed that the morphology and dimensions of these tracks, together with the state of captured grains at track termini, may be linked to the size, velocity, and density of the impacting cosmic dust grain. Here, we present the results of laboratory hypervelocity impact experiments, during which cosmic dust analog particles (diameters of between 0.2 and 0.4 μm), composed of olivine, orthopyroxene, or an organic polymer, were accelerated onto Stardust flight‐spare low‐density (approximately 0.01 g cm−3) silica aerogel. The impact velocities (3–21 km s−1) were chosen to simulate the range of velocities expected during Stardust's interstellar dust (ISD) collection phases. Track lengths and widths, together with the success of particle capture, are analyzed as functions of impact velocity and particle composition, density, and size. Captured terminal particles from low‐density organic projectiles become undetectable at lower velocities than those from similarly sized, denser mineral particles, which are still detectable (although substantially altered by the impact process) at 15 km s−1. The survival of these terminal particles, together with the track dimensions obtained during low impact speed capture of small grains in the laboratory, indicates that two of the three best Stardust candidate extraterrestrial grains were actually captured at speeds much lower than predicted. Track length and diameters are, in general, more sensitive to impact velocities than previously expected, which makes tracks of particles with diameters of 0.4 μm and below hard to identify at low capture speeds (<10 km s−1). Therefore, although captured intact, the majority of the interstellar dust grains returned to Earth by Stardust remain to be found.