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Romanovskaya Anna A. Korotkov Vladimir N. Polumieva Polina D. Trunov Alexander A. Vertyankina Victoria Yu. Karaban Rodion T. 《Mitigation and Adaptation Strategies for Global Change》2020,25(4):661-687
Mitigation and Adaptation Strategies for Global Change - This work aims to assess the dynamics of net greenhouse gas (GHG) emissions and removals, as well as analyse the mitigation potential for... 相似文献
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Alice D'Amico Danilo Buca Giuseppe Rizzo Asma Khalil Claudia Silvi Alexander Makatsariya Luigi Nappi Marco Liberati Francesco D'Antonio 《黑龙江环境通报》2021,41(4):391-399
The main aim of this systematic review was to explore the outcome of fetuses with isolated echogenic bowel (EB) on antenatal ultrasound. Inclusion criteria were singleton pregnancies with isolated EB no associated major structural anomalies at the time of diagnosis. The outcomes observed were: chromosomal anomalies, cystic fibrosis (CF), associated structural anomalies detected only at follow-up scans and at birth, regression during pregnancy, congenital infections, intra-uterine (IUD), neonatal (NND) and perinatal (PND) death. Twenty-five studies (12 971 fetuses) were included. Chromosomal anomalies occurred in 3.3% of the fetuses, mainly Trisomy 21 and aneuploidies involving the sex chromosomes. Cystic fibrosis occurred in 2.2%. Congenital infections affected 2.2%, mainly congenital Cytomegalovirus (CMV) infection. The majority of fetuses with EB experienced regression or disappearance of the EB at follow-up scans. Associated anomalies were detected at a follow-up scan in 1.8%. Associated anomalies were detected at birth and missed at ultrasound in 2.1% of cases. IUD occurred in 3.2% of cases while the corresponding figures for NND and PND were 0.4% and 3.1%. Fetuses with EB are at increased risk of adverse perinatal outcome, highlighting the need for a thorough antenatal management and postnatal follow-up. Assessment during pregnancy and after birth should be performed in order to look for signs of fetal aneuploidy, congenital infections and associated structural anomalies. 相似文献
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Penaeus merguiensis de Man systematically searches the substratum and removes small particles of food from it using the small chelae of the first three pairs of pereiopods. One or more chelae are used to transfer food particles to the mouth. The propus and dactylus of these limbs bear numerous setae arranged in discrete groups along the length of the segments. The tip of each seta is elaborately sculptured and has a large sub-terminal pore. It is probable that these are chemosensory organs responsible for discriminating edible from non-edible material. Proximal to almost every setal group is a much-branched seta (rarely two) which probably measures the depth to which the chela has been inserted into the substratum. At the articulation of the propus and carpus of the first pereiopod are three groups of differently sculptured setae, whose function is to clean the other chelate pereiopods. An elaborate system of pegs and a ridge on the apposable fringes of the chelae might be a mechano-receptive device with a particle size discriminating function. The ridges merge into opposable terminal denticulate pads whose function is to grasp food and other particles, which may be quite small (10 to 20 m upwards). 相似文献
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V. L. Maggio L. R. Alexander V. E. Green J. B. Gill D. G. Patterson Jr. B. N. Green 《毒物与环境化学》2013,95(2-3):143-154
We present the salient characteristics of tuning procedures that have evolved from our 3 years of experience while producing large amounts of data of the highest quality. Our laboratory routinely analyzes 2,3,7,8‐substituted dioxins and furans at parts per quadrillion levels in 50–100 g of human serum samples using the VG 70S/SE stand‐alone gas chromatography/mass spectrometry (GC/MS) system at 10000 resolution (defined by 5% overlap) in the selected ion recording mode. Trace measurement of dioxins and furans in human biological matrices—for example, whole blood, serum, or adipose tissue‐requires reproducible instrument tuning within day as well as among days for quality results. Additionally, instument‐tuning procedures among operators must be reproducible to minimize operator bias because periodically different operators are used. Instrument tuning is highly subjective and argumentive; therefore, to minimize the ambiguity within our laboratory, we have standardized our technique to reproducibly tune the GC/MS system. 相似文献
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