Haptic Guidance Based on All-Optical Ultrasound Distance Sensing for Safer Minimally Invasive Fetal Surgery

By intervening during the early stage of gestation, fetal surgeons aim to correct or minimize the effects of congenital disorders. As compared to postnatal treatment of these disorders, such early interventions can often actually save the life of the fetus and also improve the quality of life of the newborn. However, fetal surgery is considered one of the most challenging disciplines within Minimally Invasive Surgery (MIS), owing to factors such as the fragility of the anatomic features, poor visibility, limited manoeuvrability, and extreme requirements in terms of instrument handling with precise positioning. This work is centered on a fetal laser surgery procedure treating placental disorders. It proposes the use of haptic guidance to enhance the overall safety of this procedure and to simplify instrument handling. A method is described that provides effective guidance by installing a forbidden region virtual fixture over the placenta, thereby safeguarding adequate clearance between the instrument tip and the placenta. With a novel application of all-optical ultrasound distance sensing in which transmission and reception are performed with fibre optics, this method can be used with a sole reliance on intraoperatively acquired data. The added value of the guidance approach, in terms of safety and performance, is demonstrated in a series of experiments with a robotic platform

Environmental cues and constraints affecting the seasonality of dominant calanoid copepods in brackish, coastal waters: a case study of Acartia, Temora and Eurytemora species in the south-west Baltic

Information on physiological rates and tolerances helps one gain a cause-and-effect understanding of the role that some environmental (bottom–up) factors play in regulating the seasonality and productivity of key species. We combined the results of laboratory experiments on reproductive success and field time series data on adult abundance to explore factors controlling the seasonality of Acartia spp., Eurytemora affinis and Temora longicornis, key copepods of brackish, coastal and temperate environments. Patterns in laboratory and field data were discussed using a metabolic framework that included the effects of ‘controlling’, ‘masking’ and ‘directive’ environmental factors. Over a 5-year period, changes in adult abundance within two south-west Baltic field sites (Kiel Fjord Pier, 54°19′89N, 10°09′06E, 12–21 psu, and North/Baltic Sea Canal NOK, 54°20′45N, 9°57′02E, 4–10 psu) were evaluated with respect to changes in temperature, salinity, day length and chlorophyll a concentration. Acartia spp. dominated the copepod assemblage at both sites (up to 16,764 and 21,771 females m−3 at NOK and Pier) and was 4 to 10 times more abundant than E. affinis (to 2,939 m−3 at NOK) and T. longicornis (to 1,959 m−3 at Pier), respectively. Species-specific salinity tolerance explains differences in adult abundance between sampling sites whereas phenological differences among species are best explained by the influence of species-specific thermal windows and prey requirements supporting survival and egg production. Multiple intrinsic and extrinsic (environmental) factors influence the production of different egg types (normal and resting), regulate life-history strategies and influence match–mismatch dynamics

Twenty years of satellite and in situ observations of surface chlorophyll-a from the northern Bay of Biscay to the eastern English Channel. Is the water quality improving?

Thevariabilityofthephytoplanktonbiomassderivedfromdailychlorophyll-a(Chl-a)satelliteimageswasinvestigated over the period 1998–2017 in the surface waters of the English Channel and the northern Bay of Biscay. Merged satellite (SeaWiFS-MODIS/Aqua-MERIS-VIIRS) Chl-a wascalculated using the OC5 Ifremeralgorithm which is optimized for moderately-turbid waters. The seasonal cycle in satellite-derived Chl-a was comparedwithinsitumeasurementsmadeatsevencoastalstationslocatedinthesouthernsideoftheEnglish ChannelandinthenorthernBayofBiscay.TheresultsfirstlyshowedthatthesatelliteChl-aproduct,derived from a suite of space-borne marine reflectance data, is in agreement with the coastal observations. For compliancewiththedirectivesoftheEuropeanUniononwaterquality,time-seriesof6-yearmovingaverageofChlawereassessedovertheregion.Acleardeclinewasobservedinthemeanand90thpercentileofChl-aatstations locatedinthemixedwatersoftheEnglishChannel.Thetime-seriesatthestationslocatedintheBayofBiscay showedyearlyfluctuationswhichcorrelatedwellwithriverdischarge,butnooverallChl-atrendwasobserved. IntheEnglishChannel,theshapeoftheseasonalcycleinChl-achangedovertime.Narrowerpeakswereobservedinspringattheendofthestudiedperiod,indicatinganearlierlimitationbynutrients.Monthlyaverages of satellite Chl-a, over theperiods 1998–2003and2012–2017,exhibitedspatial andtemporalpatternsin the evolutionofthephytoplanktonbiomasssimilartotheseobservedatthesevencoastalstations.Boththeinsitu andsatelliteChl-atimes-seriesshowedadecreaseinChl-aintheEnglishChannelinMay,JuneandJuly.This trendinphytoplanktonbiomassiscorrelatedwithlowerriverdischargesattheendoftheperiodandaconstant reduction in the riverine input of phosphorus through improvements in the water quality of the surrounding rivercatchments

Eutrophication in marine waters: harmonization of MSFD methodological standards at EU level

The Marine Strategy Framework Directive (MSFD) establishes the framework for the protection, conservation and sustainable use of the marine environment at the Union level. Because of its potential negative effects on the marine water quality, eutrophication is one of the criteria assessed under MSFD. This report presents the results of the joint work between JRC and a network of Member States (MS) eutrophication designated experts to assess the level of harmonization in Eutrophication methodological standards and threshold definition at regional and EU level. The information compiled at regional and national level showed that although methodologies are defined already for all the criteria, the degree of harmonization of methodological approaches across MS and regions is in some cases very low. In addition further developments are needed for some regions to agree on common indicators and threshold values. Based on these results the report highlights existing gaps and proposes recommendations to improve the eutrophication assessment framework at EU level.JRC.D.2-Water and Marine Resource

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Higher estradiol levels are associated with lower neonatal birthweight after fresh and frozen embryo transfers. A cohort study of 3631 singleton IVF pregnancies

Aim: To assess the birthweight of neonates conceived after fresh and frozen embryo transfers (FET) and, if different, to investigate whether estradiol levels during the late follicular phase were associated with the observed difference. Methods: Singleton pregnancies from fresh and FET transfers between January 1990 and December 2013 were compared retrospectively. A total of 2885 singleton pregnancies after fresh embryo transfer and 746 after FET were analyzed. Obstetric and neonatal outcomes were compared between fresh and FET cycles. Results: The singletons born after FET were found to have a significantly higher birth weight (3313 g), compared to those born after fresh embryo transfer (3143 g); p <.001. The main predictor of this difference was found to be estradiol levels at the end of the follicular phase. The difference in birthweight was inversely correlated to estradiol levels considering all cycles together but also considering fresh and frozen cycles separately. Conclusions: Our study demonstrates a link between high estradiol levels and low birth weight of singletons after IVF both in fresh and frozen-thawed embryo transfer cycles. It provides additional support to the involvement of hyperestrogenemia in the process of implantation and on the subsequent fetal development