Is Cardiomegaly an Indication of “Heart-Sparing Effect” in Small Fetuses?

Introduction: This study aimed to test the hypothesis that cardiac size is maintained in small fetuses presenting with cardiomegaly. Materials and Methods: We identified singleton fetuses with estimated fetal weight <10th centile and with cardiomegaly without another more likely cardiac or extra-cardiac cause. We used Z-scores for cardiac and thoracic circumferences normalized for gestational age (GA), biparietal diameter (BPD), head circumference (HC), and femur length (FL), obtained from 188 normally grown fetuses. Results: When comparing chest size, small fetuses had significantly lower thoracic circumferences median Z-scores (IQR) for GA = −4.82 (−6.15 to −3.51), BPD = −2.42 (−4.04 to −1.48), HC = −2.72 (−4.53 to −1.90), and FL = −1.60 (−2.87 to −0.71); p < 0.001 for all. When comparing heart size, small fetuses showed lower cardiac circumferences median Z-scores (IQR) for GA = −1.59 (−2.79 to −0.16); p < 0.001, similar cardiac circumferences Z-scores for BPD = 0.29 (−0.65 to 1.28); p = 0.284 and HC = 0.11 (−1.13 to 0.96); p = 0.953, and higher cardiac circumferences Z-scores for FL = 0.94 (−0.05 to 2.13); p < 0.001. Conclusions: Our results show that in small fetuses with cardiomegaly, the heart maintains normal dimensions when normalized to cranial diameters and higher dimensions when normalized to long bones. This provides insight into cardiac adaptation to adverse intrauterine environment

The introduction of the absolute risk for the detection of fetal aneuploidies in the first-trimester screening

Purpose: Maternal age is a crucial factor in fetal aneuploidy screening, resulting in an increased rate of false-positive cases in older women and false-negative cases in younger women. The absolute risk (AR) is the simplest way to eliminate the background maternal age risk, as it represents the amount of improvement of the combined risk from the maternal background risk. The aim of this work is to assess the performance of the AR in the combined first-trimester screening for aneuploidies. Materials and methods: A retrospective validation of the AR in the combined first-trimester screening for fetal aneuploidies, in an unselected population at Altamedica Fetal-Maternal Medical Center in Rome, between March 2007 and December 2008. Results: Of 3845 women included in the study, we had a complete follow-up on 2984. We evaluated that an AR &lt; 3 would individuate 22 of 23 cases of aneuploidy with a detection rate of 95.7% (95%CI 87.3–100), a false-positive rate of 8.7% (95%CI 7.7–9.7) and a false-negative rate of 4.3% (95%CI 0–12.7). Conclusions: In our study, the AR ameliorates the detection rate for aneuploidy. Further research and a prospective study on a larger population would help us to improve the AR in detecting most cases of aneuploidy

Ultrasonographic evaluation of placental cord insertion at different gestational ages in low-risk singleton pregnancies: a predictive algorithm

Objective: To evaluate the accuracy of ultrasound in visualizing placental cord insertion (PCI) at different gestational ages in order to recommend the most feasible period during pregnancy to identify it. Secondary aim was to propose a predictive algorithm for PCI visualization. Methods: We performed a single-center, prospective cohort study. We enrolled patients with singleton low-risk pregnancies who underwent fetal ultrasound scan at different gestational ages. We excluded patients with body mass index of 30 Kg/m2 or more, uterine fibroids larger than 5 cm, high-risk pregnancies, fetal weight lower than 10° percentile or higher than 90° percentile, increased (“deep pocket” &gt; 80 mm) or decreased (“deep pocket” &lt; 20 mm) amniotic fluid. Results: Among the 468 recruited patients, the visualization of PCI was not possible in 5.77% of the cases. Furthermore, we showed that PCI visualization was lower as the gestational age increased (p = 0.049) and more difficult in case of posterior placenta (p = 0.001). Conclusions: PCI should be evaluated in the first trimester or as early as possible during the second trimester. Moreover, we propose a feasible model to predict the possibility of PCI visualization according to gestational age and uterine site of implantation

Uniform Circle Formation for Swarms of Opaque Robots with Lights

The Uniform Circle Formation problem requires a swarm of mobile agents, arbitrarily positioned onto the plane, to move on the vertices of a regular polygon. Each agent, customarily called robot, acts through a sequence of look-compute-move cycles. The robots do not store past actions/system snapshots. They are anonymous and cannot be dis- tinguished by their appearance and do not have a common coordinate system (origin and axis) and chirality. The system is fully synchronous in that all robots have a common clock/notion of time regulating cycles. From the literature, the Uniform Circle Formation problem is recently known to be solvable in a system where robots are punctiform or fat, but in both cases transparent: no robot obstructs the visibility of any other robot. Here, we solve the Uniform Circle Formation problem within a more realistic opaque robot system, i.e., robots may have obstructed visi- bility due to collinearities. Yet, our robots are assumed to be punctiform and luminous, i.e., equipped with a persistent light assuming different colors. This latter peculiarity represents the only way robots have to communicate. Our proposed algorithm uses a constant number of look- compute-move cycles as well as a constant number of colors

Morpho-acoustic characterization of natural seepage features near the Macondo Wellhead (ECOGIG site OC26, Gulf of Mexico)

OC26 (R/V Oceanus Site 26) is one of three primary sites selected for study by the Ecosystem Impact of Oil and Gas Inputs to the Gulf (ECOGIG) consortium to determine the impacts of natural seepage versus large pulse inputs of hydrocarbons into the Gulf of Mexico (GOM) and to chart the long-term effects and mechanisms of ecosystem recovery from the Deep Water Horizon Oil Spill in 2010. OC26 is located on the western slope of the Gloria Dome, about five kilometers south-east of the Macondo wellhead. In 2011, the site was visited by the NOAA research vessel Okeanos Explorer. During this cruise, several natural oil/gas plumes originating from the seabed were identified. In order to establish precise locations for these naturally occurring sources of hydrocarbons and to inform biogeochemical and biological studies of the water-column, the seafloor, and the shallow subseafloor in the wake of the Deep Water Horizon spill, we conducted several Autonomous Underwater Vehicle (AUV) surveys. The surveys were designed to include swath bathymetry, chirp sub-bottom profiles, and seafloor still photos to augment the Okeanos Explorer and the 2012 ECOGIG Falkor multibeam bathymetric and water column data. These AUV high resolution datasets were collected to provide in-depth geophysical analyses of seafloor morphology and to link, where possible, morphological features to the subsurface structure and plumbing system at this site where natural seepage possibly intersects hydrocarbon inputs from the spill. The site exhibits many morphological seafloor features: depressions, elongated erosional structures, dome-shaped mud volcanoes/mounds, fault traces, and round pockmarks. Seabed photos show the presence of gas hydrate outcrops and benthic communities in the vicinity of maximum seafloor backscatter intensities and many of the morphological features. Subsurface profiles show gas-related anomalies (blanking and acoustic wipeout) where pockmarks, mud volcanoes/mounds and depressions are located. In addition to the discovery of novel seafloor features, these studies provide definitive links between seafloor seeps and particular morphologies and communities, contributing to the fundamental understanding of seeps in the deep sea. (C) 2016 Published by Elsevier Ltd

Dangerous graphs

Anomalies and faults are inevitable in computer networks, today more than ever before. This is due to the large scale and dynamic nature of the networks used to process big data and to the ever-increasing number of ad-hoc devices. Beyond natural faults and anomalies occurring in a network, threats proceeding from attacks conducted by malicious intruders must be considered. Consequently, there is often a need to quickly isolate and even repair a fault in a network when it appears. Furthermore, despite the presence in a network of faults stemming from malicious entities, we need to identify the latter and their behaviours, and develop protocols resilient to their attacks. Thus, defining models to capture the dangers inherent to various faults, anomalies and threats in a network and studying such threats, has become increasingly important and popular. Threats in networks can be of two kinds: either mobile or stationary. A malicious mobile process can move along the network, whereas a stationary harmful process resides in a host. One of the most studied models for stationary harmful processes is the black hole, which was introduced by Dobrev, Flocchini, Prencipe and Santoro in 2001. A black hole models a network node in which a destructive process deletes any visiting agent or incoming data upon arrival, without leaving any observable trace. Conversely, a network may face one or more malicious mobile processes infecting one or more nodes. Given both kinds of threats, a first crucial task consists in searching for and reporting as quickly as possible the location all faulty nodes while using a minimum number of mobile agents. In general, the main issue is to identify the minimal hypotheses under which faulty nodes can be found. This problem has been investigated in both asynchronous and synchronous networks. A corollary task is to make sure that the protocols designed for solving problems such as gathering and transferring data still work despite the presence of one or more faulty nodes. In this chapter, we review the state-of-the-art of research pertaining to the presence of faulty nodes in a network. We discuss different models in synchronous and asynchronous networks and for different communication and computation capabilities of the agents. We also address relevant computational issues and present algorithmic techniques and impossibility results