Expected-value bias in routine third-trimester growth scans.

OBJECTIVES: Operators performing fetal growth scans are usually aware of the gestational age of the pregnancy, which may lead to expected-value bias when performing biometric measurements. We aimed to evaluate the incidence of expected-value bias in routine fetal growth scans and assess its impact on standard biometric measurements. METHODS: We collected prospectively full-length video recordings of routine ultrasound growth scans coupled with operator eye tracking. Expected value was defined as the gestational age at the time of the scan, based on the estimated due date that was established at the dating scan. Expected-value bias was defined as occurring when the operator looked at the measurement box on the screen during the process of caliper adjustment before saving a measurement. We studied the three standard biometric planes on which measurements of head circumference (HC), abdominal circumference (AC) and femur length (FL) are obtained. We evaluated the incidence of expected-value bias and quantified the impact of biased measurements. RESULTS: We analyzed 272 third-trimester growth scans, performed by 16 operators, during which a total of 1409 measurements (354 HC, 703 AC and 352 FL; including repeat measurements) were obtained. Expected-value bias occurred in 91.4% of the saved standard biometric plane measurements (85.0% for HC, 92.9% for AC and 94.9% for FL). The operators were more likely to adjust the measurements towards the expected value than away from it (47.7% vs 19.7% of measurements; P < 0.001). On average, measurements were corrected by 2.3 ± 5.6, 2.4 ± 10.4 and 3.2 ± 10.4 days of gestation towards the expected gestational age for the HC, AC, and FL measurements, respectively. Additionally, we noted a statistically significant reduction in measurement variance once the operator was biased (P = 0.026). Comparing the lowest and highest possible estimated fetal weight (using the smallest and largest biased HC, AC and FL measurements), we noted that the discordance, in percentage terms, was 10.1% ± 6.5%, and that in 17% (95% CI, 12-21%) of the scans, the fetus could be considered as small-for-gestational age or appropriate-for-gestational age if using the smallest or largest possible measurements, respectively. Similarly, in 13% (95% CI, 9-16%) of scans, the fetus could be considered as large-for-gestational age or appropriate-for-gestational age if using the largest or smallest possible measurements, respectively. CONCLUSIONS: During routine third-trimester growth scans, expected-value bias frequently occurs and significantly changes standard biometric measurements obtained. © 2019 the Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology

GASTOF: Ultra-fast ToF forward detector for exclusive processes at the LHC

GASTOF (Gas Time-of-Flight) detector is a Cherenkov detector proposed for very precise (10--20 ps) arrival time measurements of forward protons at some 420 m from the central detectors of CMS and ATLAS. Such an excellent time resolution will allow by z-by-timing technique for precise measurement of the z-coordinate of the event vertex in exclusive production at the LHC, when two colliding protons are scattered at very small angles. In the paper we present first GASTOF prototype, simulations of its performance as well as first tests using a cosmic muon telescope.Comment: 6 pages, 3 figures, presented at the conference ''Physics at LHC'', Krakow, June 200

The role of dwelling type when estimating the effect of magnetic fields on childhood leukemia in the California Power Line Study (CAPS).

PurposeThe type of dwelling where a child lives is an important factor when considering residential exposure to environmental agents. In this paper, we explore its role when estimating the potential effects of magnetic fields (MF) on leukemia using data from the California Power Line Study (CAPS). In this context, dwelling type could be a risk factor, a proxy for other risk factors, a cause of MF exposure, a confounder, an effect-measure modifier, or some combination.MethodsWe obtained information on type of dwelling at birth on over 2,000 subjects. Using multivariable-adjusted logistic regression, we assessed whether dwelling type was a risk factor for childhood leukemia, which covariates and MF exposures were associated with dwelling type, and whether dwelling type was a potential confounder or an effect-measure modifier in the MF-leukemia relationship under the assumption of no-uncontrolled confounding.ResultsA majority of children lived in single-family homes or duplexes (70%). Dwelling type was associated with race/ethnicity and socioeconomic status but not with childhood leukemia risk, after other adjustments, and did not alter the MF-leukemia relationship upon adjustment as a potential confounder. Stratification revealed potential effect-measure modification by dwelling type on the multiplicative scale.ConclusionDwelling type does not appear to play a significant role in the MF-leukemia relationship in the CAPS dataset as a leukemia risk factor or confounder. Future research should explore the role of dwelling as an effect-measure modifier of the MF-leukemia association

Swift J164449.3+573451 event: generation in the collapsing star cluster?

We discuss the multiband energy release in a model of a collapsing galactic nucleus, and we try to interpret the unique super-long cosmic gamma-ray event Swift J164449.3+573451 (GRB 110328A by early classification) in this scenario. Neutron stars and stellar-mass black holes can form evolutionary a compact self-gravitating subsystem in the galactic center. Collisions and merges of these stellar remnants during an avalanche contraction and collapse of the cluster core can produce powerful events in different bands due to several mechanisms. Collisions of neutron stars and stellar-mass black holes can generate gamma-ray bursts (GRBs) similar to the ordinary models of short GRB origin. The bright peaks during the first two days may also be a consequence of multiple matter supply (due to matter release in the collisions) and accretion onto the forming supermassive black hole. Numerous smaller peaks and later quasi-steady radiation can arise from gravitational lensing, late accretion of gas onto the supermassive black hole, and from particle acceleration by shock waves. Even if this model will not reproduce exactly all the Swift J164449.3+573451 properties in future observations, such collapses of galactic nuclei can be available for detection in other events.Comment: 7 pages, replaced by the final versio

Reflection and transmission of line-source excited pulsed em fields at a thin, high-contrast layer with dielectric and conductive properties

A methodology is presented for analytically modeling the reflection and transmission of line-source excited pulsed electromagnetic fields fields at a thin, planar, high-contrast layer with dielectric and conductive properties. Closed-form time-domain expressions are derived for the field components in a two-dimensional setting via an extension of the Cagniard-DeHoop method. © 2011 IEEE.published_or_final_versionThe 2011 IEEE International Symposium on Antennas and Propagation (APSURSI), Spokane, WA., 3-8 July 2011. In IEEE APSURSI Digest, 2011, p. 2404-240

Time-domain field responses of the thin, high-contrast, finely layered structure in IC packagings

The thin, high-contrast, fine layers with dielectric and conductive properties, such as ground planes, are feature structures in IC packagings. Their responses to the pulsed electromagnetic field is important both theoretically and practically. In this paper, a new semi-analytical method is proposed to model the interaction of the layer with an incident electromagnetic field via a boundary condition that expresses the in-plane conduction and contrast electric polarization currents in terms of the exciting incident field by relating the jump in the tangential component of the magnetic field strength across the layer in terms of the (continuous) tangential component of the electric field strength in the layer. Expressions for pulse shapes of the reflected and transmitted fields are conveniently obtained based on this method. It provides a novel angle to investigate the ground plane effects inside IC packagings. ©2010 IEEE.published_or_final_versionThe 19th IEEE Conference on Electrical Performance of Electronic Packaging and Systems (EPEPS 2010), Austin, TX., 25-27 October 2010. In Proceedings of 19th EPEPS, 2010, p. 233-23

A Doctor Facing Turbulent Times: Antoni Tomasz Jurasz, Citizen of the World

The eponymous of the Jurasz procedure is Antoni Tomasz Jurasz (1882–1961). The procedure is a standard approach to treating mature pancreatic pseudocysts that are in contact with the stomach, although recent advances in instrumentation have empowered surgeons to perform pseudocystogastrostomy laparoscopically for this problem. Dr. Jurasz was born in Germany but felt himself as Polish as his ancestors. He graduated from Heidelberg with a degree in medicine. Over the following years, he developed a German surgery school, especially helping with the achievements of Erich Lexer and Erwin Payr. During the period between World Wars I and II, Jurasz chaired and led the Surgery Clinic of Poznan University in Poland; and he gave lectures and performed public operations abroad. These activities, together with articles published in German-, French-, and English-language medical journals, made him a world-renowned figure in the field of abdominal and thyroid surgery. During World War II, he revealed exceptional traits, taking part in the September Campaign in Poland as a surgeon. He then organized the Polish School of Medicine and the Paderewski Hospital in Edinburgh. Despite his outstanding mind, generosity, and merits, A. T. Jurasz became persona non grata in Communist Poland, which ultimately persuaded him to emigrate to the United States

Free-throw shooting during dual-task performance: Implications for attentional demand and performance

In this study, the dual-task paradigm was used to determine peak attentional demand during the free-throw process. Thirty participants completed 40 free-throw trials. The free throw was the primary task, but participants also verbally responded to a tone administered at one of four probe positions (PP). Repeated measures analysis of variance showed no significant difference in free-throw performance across PPs, indicating participants were able to keep the free throw as the primary task. Repeated measures analysis of response time (RT) showed significant differences, with RT at PP1 (preshot routine) and PP2 (first upward motion of the ball) significantly higher than baseline RT. These results suggest that PP1 requires the greatest attentional demand, followed by PP2