GI2T/REGAIN spectro-interferometry with a new infrared beam combiner

We have built an infrared beam combiner for the GI2T/REGAIN interferometer of the Observatoire de la Cote d'Azur. The beam combiner allows us to record spectrally dispersed Michelson interference fringes in the near-infrared J-, H- or K-bands. The beam combiner has the advantage that Michelson interferograms can simultaneously be recorded in about 128 different spectral channels. The tilt of the spectrally dispersed fringes is a measure of the instantaneous optical path difference. We present the optical design of the beam combiner and GI2T/REGAIN observations of the Mira star R Cas with this beam combiner in the spectral range of 2.00 micron - 2.18 micron (observations on 22 and 25 August 1999; variability phase 0.08; V-magnitude approx. 6; seven baselines between 12m and 24m; reference stars Vega and Beta Peg). The spectrograph of the beam combiner consists of an anamorphotic cylindrical lens system, an image plane slit, and a grism. A system of digital signal processors calculates the ensemble average power spectrum of the spectrally dispersed Michelson interferograms and the instantaneous optical path difference error in real time. From the observed R Cas visibilities at baselines 12.0m, 13.8m and 13.9m, a 2.1 micron uniform-disk diameter of 25.3mas +/-3.3mas was derived. The unusually high visibility values at baselines >16m show that the stellar surface of R Cas is more complex than previously assumed. The visibility values at baselines >16m can be explained by high-contrast surface structure on the stellar surface of R Cas or other types of unexpected center-to-limb variations. The R Cas observations were compared with theoretical Mira star models yielding a linear Rosseland radius of 276Rsun +/-66Rsun and an effective temperature of 2685K+/-238K for R Cas at phase 0.08.Comment: 10 pages, 6 figures, see also http://www.mpifr-bonn.mpg.de/div/speckle, SPIE conf 4006 "Interferometry in Optical Astronomy", in pres

Perioperative morbidity of different operative approaches in early cervical carcinoma: a systematic review and meta-analysis comparing minimally invasive versus open radical hysterectomy

Purpose: Radical hysterectomy and pelvic lymphadenectomy is the standard treatment for early cervical cancer. Studies have shown superior oncological outcome for open versus minimal invasive surgery, but peri- and postoperative complication rates were shown vice versa. This meta-analysis evaluates the peri- and postoperative morbidities and complications of robotic and laparoscopic radical hysterectomy compared to open surgery. Methods: Embase and Ovid-Medline databases were systematically searched in June 2020 for studies comparing robotic, laparoscopic and open radical hysterectomy. There was no limitation in publication year. Inclusion criteria were set analogue to the LACC trial. Subgroup analyses were performed regarding the operative technique, the study design and the date of publication for the endpoints intra- and postoperative morbidity, estimated blood loss, hospital stay and operation time. Results: 27 studies fulfilled the inclusion criteria. Five prospective, randomized-control trials were included. Meta-analysis showed no significant difference between robotic radical hysterectomy (RH) and laparoscopic hysterectomy (LH) concerning intra- and perioperative complications. Operation time was longer in both RH (mean difference 44.79 min [95% CI 38.16; 51.42]), and LH (mean difference 20.96 min; [95% CI − 1.30; 43.22]) than in open hysterectomy (AH) but did not lead to a rise of intra- and postoperative complications. Intraoperative morbidity was lower in LH than in AH (RR 0.90 [0.80; 1.02]) as well as in RH compared to AH (0.54 [0.33; 0.88]). Intraoperative morbidity showed no difference between LH and RH (RR 1.29 [0.23; 7.29]). Postoperative morbidity was not different in any approach. Estimated blood loss was lower in both LH (mean difference − 114.34 [− 122.97; − 105.71]) and RH (mean difference − 287.14 [− 392.99; − 181.28]) compared to AH, respectively. Duration of hospital stay was shorter for LH (mean difference − 3.06 [− 3.28; − 2.83]) and RH (mean difference − 3.77 [− 5.10; − 2.44]) compared to AH. Conclusion: Minimally invasive radical hysterectomy appears to be associated with reduced intraoperative morbidity and blood loss and improved reconvalescence after surgery. Besides oncological and surgical factors these results should be considered when counseling patients for radical hysterectomy and underscore the need for new randomized trials. © 2021, The Author(s)

A Comprehensive & Systematic Study of Coincidence Time Resolution and Light Yield Using Scintillators of Different Size and Wrapping

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TOPBP1 missense variant Arg309Cys and breast cancer in a German hospital-based case-control study

The DNA double strand break repair gene TOPBP1 has been suggested as a breast cancer susceptibility gene and a missense variant Arg309Cys was observed at elevated frequency in familial breast cancer cases compared to healthy controls from Finland. We found the Arg309Cys allele at a 13% carrier frequency in a hospital-based series of 1064 German breast cancer patients and at a 14% carrier frequency in 1014 population controls (OR 0.89, 95%CI 0.69-1.15; p = 0.4). Arg309Cys carriers were not enriched among patients with a family history of breast cancer (OR = 0.87, 95%CI 0.53-1.43, p = 0.6) and were slightly underrepresented in patients with bilateral disease (OR = 0.49, 95%CI = 0.24-0.99; p = 0.047). In the latter group, the mean age at diagnosis was 62 years in carriers and 54 years in non-carriers (p = 0.004). We conclude that there is no evidence for the TOPBP1*Arg309Cys variant to confer an increased risk for breast cancer in the German population

Charge collection properties of TowerJazz 180 nm CMOS Pixel Sensors in dependence of pixel geometries and bias parameters, studied using a dedicated test-vehicle: the Investigator chip

This paper contains a compilation of parameters influencing the charge collection process extracted from a comprehensive study of partially depleted Monolithic Active Pixel Sensors with small (<25 um$^2$) collection electrodes fabricated in the TowerJazz 180 nm CMOS process. These results gave guidance for the optimisation of the diode implemented in ALPIDE, the chip used in the second generation Inner Tracking System of ALICE, and serve as reference for future simulation studies of similar devices. The studied parameters include: reverse substrate bias, epitaxial layer thickness, charge collection electrode size and the spacing of the electrode to surrounding in-pixel electronics. The results from pixels of 28 um pitch confirm that even in partially depleted circuits, charge collection can be fast (<10 ns), and quantify the influence of the parameters onto the signal sharing and amplitudes, highlighting the importance of a correct spacing between wells and of the impact of the reverse substrate bias

Time based readout of a silicon photomultiplier (SiPM) for Time Of Flight Positron Emission Tomography (TOF-PET)

Time of flight (TOF) measurements in positron emission tomography (PET) are very challenging in terms of timing performance, and should achieve ideally less than 100ps FWHM precision. We present a time-based differential technique to read out SiPMs that has less than 25ps rms electronic jitter. The novel readout is a fast front end circuit (NINO) based on a first stage differential current mode amplifier with 20input resistance. Therefore the amplifier inputs are connected differentially to the SiPM’s anode and cathode ports. The leading edge of the output signal provides the time information, while the trailing edge provides the energy information. Based on a Monte Carlo photon-generation model, SPICE simulations were run with a 3x3mm2 SiPM-model, read out with a differential current amplifier. The results of these simulations are presented here and compared with experimental data obtained with a 3x3x15mm3 LSO crystal coupled to a SiPM. The measured time coincidence precision is interpreted by the combined Monte Carlo/ SPICE simulation, as well as by Poisson statistics