bluuebunny/crossref_metadata_2025 huggingface dataset:
Short‐Lived Orthobenzyne Complexes with Early Transition Metals of Group IV. First Direct Characterization and Electronic Cartography by Coupling FVT/UV‐PES with Calculations
Authors: Miqueu Karinne , Labat Stéphane , Daiann Sosa Carrizo E. , Sotiropoulos Jean‐Marc
Published: April 2018

Short‐lived η2‐benzyne metallocene complexes [Cp2M(η2‐c‐C6H4)] with group IV metals are important intermediates in organic chemistry, their olefin insertion products being building blocks for aromatic and heterocyclic compounds. For the first time, an electronic cartography of these short‐lived species has been obtained through the determination of their ionization potentials. They have been directly characterized in the gas phase by UV photoelectron spectroscopy, by monitoring, in situ, the thermal β‐H abstraction of benzene from Cp2MPh2. The metal impacts the energetic position of the σMCorbitals more strongly than the πCCbenzyneorbital (HOMO). This study has been supported by DFT calculations and by NBO, AIM, ELF, CDA, and EDA analyses. The electronic structure of the transient Cp2Ti(η2‐c‐C6H4) complex is peculiar and slightly differs from that of the analogous zirconium and hafnium complexes. The electronic structure is a combination of a metallacyclic and a π complex, whereas with Hf and Zr, the metallacyclic structure appears to be more representative.
Deazapurine Analogues Bearing a 1H‐Pyrazolo[3,4‐b]pyridin‐3(2H)‐one Core: Synthesis and Biological Activity
Authors: Supe Linda , Afzal Saira , Mahmood Abid , Ejaz Syeda Abida , Hein Martin , Iaroshenko Viktor O. , Villinger Alexander , Lecka Joanna , Sévigny Jean , Iqbal Jamshed , Langer Peter
Published: April 2018

A new methodology for the synthesis of fluorinated and non‐fluorinated 1H‐pyrazolo[3,4‐b]pyridin‐3‐ones was developed. The reactions proceed by cyclization of electron‐rich 3‐amino‐1H‐pyrazol‐5(4H)‐ones with 1,3‐diketones and the products were obtained in good to excellent yields and with excellent regioselectivity. The products, which can be regarded as deazapurine analogues, were tested for the alkaline phosphatase (h‐TNAP and h‐IAP) and nucleotide pyrophosphatase/phosphodiesterase (h‐NPP1 and h‐NPP3) inhibition profile. Most of the derivatives exhibited selective and potent inhibition on tissue non‐specific and intestinal alkaline phosphatase and nucleotide pyrophosphatase (NPP1 and NPP3) enzymes. Possible binding modes of the most potent inhibitors were studied by molecular docking analysis.
Synthesis, Characterization, Sensing, and Coordination Properties of trans‐Homoporphodimethenes
Authors: Isar Prosenjit , Rajeswara Rao M. , Ravikanth Mangalampalli
Published: April 2018

Four different meso‐substituted trans‐homoporphodimethenes containing four five‐membered heterocycles connected through two sp3 meso carbon atoms in a trans fashion and three sp2 meso carbon atoms were synthesized in decent yields through the condensation reactions of 1 equiv. of an appropriate 2,3‐dithienyl‐2‐butenediol with 1 equiv. of meso‐(p‐nitrophenyl)dipyrromethane under mild acid‐catalyzed conditions. All of the trans‐homoporphodimethenes were characterized by HRMS as well as 1D and 2D NMR spectroscopy techniques, and the structure of one of the trans‐homoporphodimethenes was determined by X‐ray crystallography. The crystal analysis indicated that the macrocycle is highly distorted owing to the presence of two meso sp3 carbon atoms and attains a boat conformation. Anion‐sensing studies indicated that these macrocycles can be used as selective fluorescence turn‐on sensors for toxic CN– ions. The trans‐homoporphodimethenes readily form BF2 complexes through treatment with BF3·OEt2 in toluene in the presence of diisopropylethylamine at 70–80 °C for 4 h. The BF2 complexes of the trans‐homoporphodimethenes showed fluorescence bands bathochromically shifted by ca. 80 nm compared with that of BODIPY (4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene) as well as large Stokes shifts.
Synthesis of Isoquinolines through IrIII‐Catalyzed C–H Activation/Annulation from Benzimidates with Hydroxylisopropylalkynes
Authors: Liu Mingliang , Gong Wanchun , You Erli , Zhang Haizhen , Shi Lei , Cao Weiguo , Shi Jingjing
Published: April 2018

An IrIII‐catalyzed cascade reaction consisting of C–H activation/annulation of benzimidates with hydroxylisopropylalkynes is reported. A broad range of isoquinolines has been prepared in one step with good functiona‐group tolerance and high efficiency.
Electrocatalytic Discrimination between Dopamine and Norepinephrine at Graphite and Basal Plane HOPG Electrodes
Authors: Álvarez‐Martos Isabel , Ferapontova Elena E.
Published: April 2018

Understanding the regulatory mechanisms of neurotransmission is impossible without in vivo monitoring of neurotransmitters’ (NTs) transformation in the brain, and that can be performed by a variety of electrochemical methods. Close redox potentials of such NTs as catecholamines, however, impede their specific analysis in systems where they do co‐exist. Here, we studied the kinetics of dopamine and norepinephrine redox transformations on glassy carbon, micro‐structured spectroscopic graphite, and basal plane HOPG electrodes. We showed that in contrast to the “positive electrocatalysis” on porous microstructured graphite electrodes, “negative electrocatalysis” at the HOPG electrodes, displayed through slowing down of the reaction rate, allowed a ca. 0.1 V separation between dopamine and norepinephrine oxidations and individual detection of dopamine in the artificial cerebrospinal fluid. Dopamine could be detected within the 50 nM to 4 μM range with no interference from excesses of norepinephrine and ascorbic acid. The results suggest a new approach for design of the electrodes for specific analysis of dopamine in mixtures of structurally related NTs.
Ionic liquid‐based headspace in‐tube liquid‐phase microextraction coupled with CE for sensitive detection of phenols
Authors: Yue Mei‐E , Lin Qiaoyan , Xu Jie , Jiang Ting‐Fu
Published: April 2018

An ionic liquid‐based headspace in‐tube liquid‐phase microextraction (IL‐HS‐ITLPME) in‐line coupled with CE is proposed. The method is capable of quantifying trace amounts of phenols in environmental water samples. In the newly developed method, simply by placing a capillary injected with ionic liquids (IL) in the HS above the aqueous sample, volatile phenols were extracted into the IL acceptor phase in the capillary. After extraction, electrophoresis of the phenols in the capillary was carried out. Extraction parameters such as the extraction time, extraction temperature, ionic strength, volume of the sample solution, and IL types were systematically investigated. Under the optimized conditions, enrichment factors for four phenols were from 1510 to 1985. The proposed method provided a good linearity, low limits of detection (below 5.0 ng/mL), and good repeatability of the extractions (RSDs below 6.7%, n = 6). This method was then utilized to analyze two real environmental samples of Xiaoxi Lake and tap water, obtaining acceptable recoveries and precisions. Compared with the usual HS‐ITLPME for CE, IL‐HS‐ITLPME‐CE is a simple, low cost, fast, and environmentally friendly preconcentration technique.
A novel All‐in‐One electrolysis electrode and bioreactor enable better study of electrochemical effects and electricity‐aided bioprocesses
Authors: Utesch Tyll , Zeng An‐Ping
Published: April 2018

An autoclavable All‐in‐One electrolysis electrode in a rod shape assembly is developed as a new tool for bioelectrochemical systems and electricity‐aided bioprocesses. It can replace the classic two‐chamber bioelectrochemical system for electrolysis reactions, be inserted into conventional bioreactors and is easily adaptable as electrocatalytic surface or generator of super‐fine bubbles (H2 and O2) for bioconversion processes. Whereas the bioreactor itself functions as the working electrode chamber, a well‐integrated inner counter electrode chamber enables water electrolysis without the normally encountered undesired ion‐transfer effect. The efficiencies of the electrode are characterized and its advantages and usefulness compared to the classic H‐Cell bioelectrochemical system (BES) are demonstrated with glycerol fermentations by Clostridium pasteurianum DSM 525.
The effective stiffness of modern unreinforced masonry walls
Authors: Wilding Bastian Valentin , Beyer Katrin
Published: April 2018

Code design of unreinforced masonry (URM) buildings is based on elastic analysis, which requires as input parameter the effective stiffness of URM walls. Eurocode estimates the effective stiffness as 50% of the gross sectional elastic stiffness, but comparisons with experimental results have shown that this may not yield accurate predictions. In this paper, 79 shear‐compression tests of modern URM walls of different masonry typologies from the literature are investigated. It shows that both the initial and the effective stiffness increase with increasing axial load ratio and that the effective‐to‐initial stiffness ratios are approximately 75% rather than the stipulated 50%. An empirical relationship that estimates the E‐modulus as a function of the axial load and the masonry compressive strength is proposed, yielding better estimates of the elastic modulus than the provision in Eurocode 6, which calculates the E‐modulus as a multiple of the compressive strength. For computing the ratio of the effective to initial stiffness, a mechanics‐based formulation is built on a recently developed analytical model for the force‐displacement response of URM walls. The model attributes the loss in stiffness to diagonal cracking and brick crushing, both of which are taken into account using mechanical considerations. The obtained results of the effective‐to‐initial stiffness ratio agree well with the test data. A sensitivity analysis using the validated model shows that the ratio of effective‐to‐initial stiffness is for most axial load ratios and wall geometries around 75%. Therefore, a modification of the fixed ratio of effective‐to‐initial stiffness from 50% to 75% is suggested.
Interlaboratory evaluation of methods to quantify skin‐sensitizing hydroperoxides of limonene and linalool (II): Analysis in cosmetic bases
Authors: Natsch Andreas , Kern Susanne , Corbi Elise , Pérès Christophe , Nägelin Marco , Leijs Hans , van Strien Michel , Calandra Michael J. , Wang Ying
Published: April 2018

The fragrant terpenes limonene and linalool can form skin‐sensitizing hydroperoxides (HPs) upon prolonged exposure to air. Sources of exposure of consumers to sensitizing doses of HPs have not been identified, and it is not clear whether fragranced products are a relevant source. Previously this question was addressed via analytical studies on fine fragrances; however, linalool and limonene are widely used in different consumer products, especially in other leave‐on toiletries. Hence, analytical methods also need to be able to detect potential HPs in more complex consumer product matrices. Here we applied different simple extraction methods and a toolbox of analytical methods to creams and lotions. Blinded samples of a commercial skin cream and a body lotion were spiked with four different HPs at different doses. Five laboratories analysed the samples with a method based on HP reduction in the sample, followed by Extrelut® NT extraction and GC‐MS to quantify the formed alcohols. This method found an average recovery of spiked levels of 80–105%, with a relative standard deviation between laboratories of 11–25% in samples spiked with 100–200 μg g−1. Quantification was also possible in samples spiked with 20–50 μg mL−1, with a relative standard deviation between laboratories of 11–38%. Thus, this method can indirectly detect low levels of HPs in complex bases. In parallel, the same samples were analysed with three LC‐based methods directly detecting the parent HPs: LC coupled with chemiluminescence, LC‐Q‐TOF‐MS, and LC‐orbitrap‐MS. On average, the different analytes were detected with a recovery of 80–143%. No HPs were detected in the non‐spiked products, despite the fact that they do contain linalool and limonene. Results of these studies indicate that consumer exposure can now be studied routinely in different product types as the required methods are ready for roll‐out.
Genetic associations with childhood brain growth, defined in two longitudinal cohorts
Authors: Szekely Eszter , Schwantes‐An Tae‐ Hwi Linus , Justice Cristina M. , Sabourin Jeremy A. , Jansen Philip R. , Muetzel Ryan L. , Sharp Wendy , Tiemeier Henning , Sung Heejong , White Tonya J. , Wilson Alexander F. , Shaw Philip
Published: April 2018

Genome‐wide association studies (GWASs) are unraveling the genetics of adult brain neuroanatomy as measured by cross‐sectional anatomic magnetic resonance imaging (aMRI). However, the genetic mechanisms that shape childhood brain development are, as yet, largely unexplored. In this study we identify common genetic variants associated with childhood brain development as defined by longitudinal aMRI. Genome‐wide single nucleotide polymorphism (SNP) data were determined in two cohorts: one enriched for attention‐deficit/hyperactivity disorder (ADHD) (LONG cohort: 458 participants; 119 with ADHD) and the other from a population‐based cohort (Generation R: 257 participants). The growth of the brain's major regions (cerebral cortex, white matter, basal ganglia, and cerebellum) and one region of interest (the right lateral prefrontal cortex) were defined on all individuals from two aMRIs, and a GWAS and a pathway analysis were performed. In addition, association between polygenic risk for ADHD and brain growth was determined for the LONG cohort. For white matter growth, GWAS meta‐analysis identified a genome‐wide significant intergenic SNP (rs12386571, P = 9.09 × 10−9), near AKR1B10. This gene is part of the aldo‐keto reductase superfamily and shows neural expression. No enrichment of neural pathways was detected and polygenic risk for ADHD was not associated with the brain growth phenotypes in the LONG cohort that was enriched for the diagnosis of ADHD. The study illustrates the use of a novel brain growth phenotype defined in vivo for further study.
Do earthquakes trigger mud volcanoes? A case study from the southern margin of the Junggar Basin, NW China
Authors: Zhong Siling , Wan Zhifeng , Duan Benchun , Liu Dunyu , Luo Bin
Published: April 2018

Mud volcanoes are significant indicators of neotectonic activity and have important research significance. Mud volcanoes can not only be used as an important index for the long‐term evaluation of oil and gas fields but are also an important symbol for locating gas hydrates in the seabed. Additionally, the eruption of mud volcanoes will affect drilling, pipe laying, and other projects, and the eruption of large amounts of methane gas can also cause greenhouse effects and climate change. The trigger mechanisms of mud volcanoes have always been a focus of debate among geologists. In recent years, many scholars have argued that mud volcanoes are triggered by earthquake activity. However, the stress and strain caused by earthquakes and their control mechanisms on the eruption of mud volcanoes still require further study. This paper is based on the calculated results of static stresses caused by the M5.5 Wusu earthquake of May 2, 1995, the M5.4 Shawan earthquake of January 9, 1996, the M5.3 Shihezi earthquake of February 14, 2003, and the M6.3 Xinyuan–Hejing earthquake of June 30, 2012, on the Horgos, Dushanzi, Aiqigou, and Baiyanggou mud volcanoes distributed in the southern margin of the Junggar Basin, NW China. The calculated static stresses, the earthquake response characteristics of these four groups of mud volcanoes, and the continuous observational data of the Horgos mud volcanoes showed that static stresses from these earthquakes did not reach the triggering threshold, though the mud volcanoes exhibited a good relationship with earthquakes. We speculate that static stress may not be the main triggering mechanism for the mud volcanoes and that the mechanisms of earthquake triggering may be divided into two types: (a) For a mud volcano in a critical state before an earthquake, dynamic stress changes may trigger eruption of the mud volcano by increasing permeability and mobilizing magma; (b) for mud volcanoes that have not yet reached the critical eruption state before an earthquake, both static and dynamic stresses play roles in their activities.
The wmN1 enhancer region in intron 1 is required for expression of human PLP1
Authors: Hamdan Hamdan , Patyal Pankaj , Kockara Neriman T. , Wight Patricia A.
Published: April 2018

The myelin proteolipid protein gene (PLP1) encodes the most abundant protein present in myelin from the central nervous system (CNS). Its expression must be tightly controlled as evidenced by mutations that alter PLP1 dosage; both overexpression (elevated PLP1 copy number) and lack thereof (PLP1 deletion) result in X‐linked genetic disorders in man. However, not much is known about the mechanisms that govern expression of the human gene. To address this, transgenic mice were generated which utilize human PLP1 (hPLP1) sequences (proximal 6.2 kb of 5′‐flanking DNA to the first 38 bp of exon 2) to drive expression of a lacZ reporter cassette. LoxP sites were incorporated around a 1.5‐kb section of hPLP1 intron 1 since it contains sequence orthologous to the wmN1 region from mouse which, previously, was shown to augment expression of a minimally‐promoted transgene coincident with the active myelination period of CNS development. Eight transgenic lines were generated with the parental, 6.2hPLP(+)Z/FL, transgene. All lines expressed the transgene appropriately in brain as evidenced by staining with X‐gal in white matter regions and olfactory bulb. Removal of the “wmN1” region from 6.2hPLP(+)Z/FL with a ubiquitously expressed Cre‐driver caused a dramatic reduction in transgene activity. These results demonstrate for the first time that the wmN1 enhancer region: (1) is functional in hPLP1; (2) works in collaboration with its native promoter—not just a basal heterologous promoter; (3) is required for high levels of hPLP1 gene activity; (4) has a broader effect, both spatially and temporally, than originally projected with mPlp1.
ASCL1 regulates proliferation of NG2‐glia in the embryonic and adult spinal cord
Authors: Kelenis Demetra P. , Hart Emma , Edwards‐Fligner Morgan , Johnson Jane E. , Vue Tou Yia
Published: April 2018

NG2‐glia are highly proliferative oligodendrocyte precursor cells (OPCs) that are widely distributed throughout the central nervous system (CNS). During development, NG2‐glia predominantly differentiate into oligodendrocytes (OLs) to myelinate axon fibers, but they can also remain as OPCs persisting into the mature CNS. Interestingly, NG2‐glia in the gray matter (GM) are intrinsically different from those in the white matter (WM) in terms of proliferation, differentiation, gene expression, and electrophysiological properties. Here we investigate the role of the transcriptional regulator, ASCL1, in controlling NG2‐glia distribution and development in the GM and WM. In the spinal cord, ASCL1 levels are higher in WM NG2‐glia than those in the GM. This differential level of ASCL1 in WM and GM NG2‐glia is maintained into adult stages. Long‐term clonal lineage analysis reveals that the progeny of single ASCL1+ oligodendrocyte progenitors (OLPs) and NG2‐glia are primarily restricted to the GM or WM, even though they undergo extensive proliferation to give rise to large clusters of OLs in the postnatal spinal cord. Conditional deletion of Ascl1 specifically in NG2‐glia in the embryonic or adult spinal cord resulted in a significant reduction in the proliferation but not differentiation of these cells. These findings illustrate that ASCL1 is an intrinsic regulator of the proliferative property of NG2‐glia in the CNS.
Do only children have poor vision? Evidence from China's One‐Child Policy
Authors: Zhao Liqiu , Zhou Minghai
Published: April 2018

This paper examines whether only children have poor vision by exploiting the quasinatural experiment generated by the Chinese One‐Child Policy. The results suggest that being an only child increases the incidence of myopia by 9.1 percentage points. We further investigate the mechanisms through which being an only child affects the myopia and find that only children, as the only hope in a household, receive higher expectations in terms of academic performance and future educational attainment and pressure to succeed in life from parents, which contribute to the increased myopia. We also find that the school quality of only children is significantly higher than that of non‐only children. This study provides new insights into an important health consequence of One‐Child Policy in China.
On the (a)symmetry between the perception of time and space in large‐scale environments
Authors: Riemer Martin , Shine Jonathan P. , Wolbers Thomas
Published: April 2018

Cross‐dimensional interference between spatial and temporal processing is well documented in humans, but the direction of these interactions remains unclear. The theory of metaphoric structuring states that space is the dominant concept influencing time perception, whereas time has little effect upon the perception of space. In contrast, theories proposing a common neuronal mechanism representing magnitudes argue for a symmetric interaction between space and time perception. Here, we investigated space‐time interactions in realistic, large‐scale virtual environments. Our results demonstrate a symmetric relationship between the perception of temporal intervals in the supra‐second range and room size (experiment 1), but an asymmetric relationship between the perception of travel time and traveled distance (experiment 2). While the perception of time was influenced by the size of virtual rooms and by the distance traveled within these rooms, time itself affected only the perception of room size, but had no influence on the perception of traveled distance. These results are discussed in the context of recent evidence from rodent studies suggesting that subsets of hippocampal place and entorhinal grid cells can simultaneously code for space and time, providing a potential neuronal basis for the interactions between these domains.
Recent advances in understanding Leishmania donovani infection: The importance of diverse host regulatory pathways
Authors: Saha Amrita , Basu Moumita , Ukil Anindita
Published: April 2018

Invasion of host cell by pathogens induce various intracellular signalling pathways. The host cell through the initiation of these signalling circuits desperately wants to get rid of the pathogen, whereas the pathogen tries to subvert these defence strategies to create an environment for their successful survival. Leishmania spp. is not an exception. Leishmania have to evolve a range of strategic mechanisms to neutralize macrophage defensive arsenals which enable the parasite to replicate within the phagolysosome of infected host. Understanding these signalling mechanisms in detail will not only improve our basic knowledge of host‐pathogen interaction but will also help us to develop effective drug targets not only against leishmaniasis but also for many other macrophage associated diseases. © 2018 IUBMB Life, 70(7):593–601, 2018
Comparison of oocyte mRNA localization patterns in sterlet Acipenser ruthenus and African clawed frog Xenopus laevis
Authors: Pocherniaieva Kseniia , Sidova Monika , Havelka Milos , Saito Taiju , Psenicka Martin , Sindelka Radek , Kaspar Vojtech
Published: April 2018

In oocytes, RNA localization has critical implications, as assembly of proteins in particular subcellular domains is crucial to embryo development. The distribution of mRNA molecules can identify and characterize localized transcripts. The goal of this study was to clarify the origin of primordial germ cells in the oocyte body plan and to reveal the generation of cell lineages by localized RNAs. The distribution of 12 selected mRNAs in sterlet Acipenser ruthenus oocytes was investigated by qPCR tomography and compared with known patterns of mRNA localization in Xenopus laevis. We investigated the distribution of two gene clusters in the ooplasm along the animal–vegetal axis of the sturgeon oocyte, both of which showed clearly defined intracellular gradient pattern remarkably similar to their distribution in the frog oocyte. We elucidated the localization of sturgeon egg germplasm markers belonging to the vegetal group of mRNAs. The mRNAs coding otx1, wnt11, and veg1 found to be localized in the sturgeon animal hemisphere are, in contrast, distributed in the vegetal hemisphere in amphibian. Actinopterygii and Sarcopterygii, two major lineages of osteichthyan vertebrates, split about 476 Ma (Blair & Hedges, ), albeit basal lineages share conserved biological features. Acipenseriformes is one the most basal living lineages of Actinopterygii, having evolved about 200 Ma (Bemis, Birstein, & Waldman, ), contemporaneous with modern amphibians (Roelants et al., ).
Do chitons have a brain? New evidence for diversity and complexity in the polyplacophoran central nervous system
Authors: Sumner‐Rooney Lauren , Sigwart Julia D.
Published: April 2018

Molluscs demonstrate astonishing morphological diversity, and the relationships among clades have been debated for more than a century. Molluscan nervous systems range from simple ‘ladder‐like’ cords to the complex brains of cephalopods. Chitons (Polyplacophora) are assumed to retain many molluscan plesiomorphies, lacking neural condensation and ganglionic structure, and therefore a brain. We reconstructed three‐dimensional anatomical models of the nervous system in eight species of chitons in an attempt to clarify chiton neuroarchitecture and its variability. We combined new data with digitised historic slide material originally used by malacologist Johannes Thiele (1860–1935). Reconstructions of whole nervous systems in Acanthochitona fascicularis, Callochiton septemvalvis, Chiton olivaceus, Hemiarthrum setulosum, Lepidochitona cinerea, Lepidopleurus cajetanus and Leptochiton asellus, and the anterior nervous system of Schizoplax brandtii, demonstrated consistent and substantial anterior neural concentration in the circumoesophageal nerve ring. This is further organised into three concentric tracts, corresponding to the lateral, ventral and cerebral nerve cords. These represent homologues to the three main pairs of ganglia in other molluscs. Their relative size, shape and organisation are highly variable among the examined taxa, but consistent with previous studies of select species, and we formulated a set of neuroanatomical characters for chitons. These support anatomical transitions at the ordinal and subordinal levels; the identification of robust homologies in neural architecture will be central to future comparisons across Mollusca and, more broadly, Lophotrochozoa. Contrary to almost all previous descriptions, the size and structure of the chiton anterior nerve ring unambiguously qualify it as a true brain with cordal substructure.
Prograded coastal barriers provide paleoenvironmental records of storms and sea level during late Quaternary highstands
Authors: Dougherty Amy J.
Published: April 2018

Records of past shoreline evolution, storm impacts, and variations in sea level are essential to accurately assess the vulnerability of beaches to future climate change. Prograded sandy barriers provide the opportunity to utilize our understanding of coastal dynamics documented over decades to determine storm impacts over centuries and sea‐level change over millennia. Composite coastal barriers that have prograded throughout the Pleistocene and Holocene maintain, within their stratigraphy, a record of shoreline evolution extending back to when sea level was known to be higher than today (Marine Isotope Stage or MIS 5e), including high‐energy events during these late Quaternary highstands. This study utilizes ground‐penetrating radar to image the facies architecture of a composite barrier system in Bream Bay, New Zealand. The resulting stratigraphic record mapped paleo‐beachfaces with decimeter resolution spanning ∼5 kilometers from the active shoreline, bridging timescales of coastal evolution over orders of magnitude. Charting the elevation of the beachfaces provides evidence of overall sea‐level falls from +5 to +2 m above present in the Pleistocene and from a ∼2‐m mid‐Holocene highstand. Sixty paleo‐beachfaces with distinct storm‐related signatures are identified within the Pleistocene morphostratigraphy. In the past ∼6,000 years 25 major storm events were recorded, giving an average period between events of ∼230 years. These unprecedented data provide insight, as well as input to forecasting models, needed to mitigate and manage future impacts of global warming.
The fragility of statistically significant findings from randomized trials in head and neck surgery
Authors: Noel Christopher W. , McMullen Caitlin , Yao Christopher , Monteiro Eric , Goldstein David P. , Eskander Antoine , de Almeida John R.
Published: April 2018

Objectives

The Fragility Index (FI) is a novel tool for evaluating the robustness of statistically significant findings in a randomized control trial (RCT). It measures the number of events upon which statistical significance depends. We sought to calculate the FI scores for RCTs in the head and neck cancer literature where surgery was a primary intervention.

Data Sources

Potential articles were identified in PubMed (MEDLINE), Embase, and Cochrane without publication date restrictions.

Review Methods

Two reviewers independently screened eligible RCTs reporting at least one dichotomous and statistically significant outcome. The data from each trial were extracted and the FI scores were calculated. Associations between trial characteristics and FI were determined.

Results

In total, 27 articles were identified. The median sample size was 67.5 (interquartile range [IQR] = 42–143) and the median number of events per trial was 8 (IQR = 2.25–18.25). The median FI score was 1 (IQR = 0–2.5), meaning that changing one patient from a nonevent to an event in the treatment arm would change the result to a statistically nonsignificant result, or P > .05. The FI score was less than the number of patients lost to follow‐up in 71% of cases. The FI score was found to be moderately correlated with P value (ρ = −0.52, P = .007) and with journal impact factor (ρ = 0.49, P = .009) on univariable analysis. On multivariable analysis, only the P value was found to be a predictor of FI score (P = .001).

Conclusions

Randomized trials in the head and neck cancer literature where surgery is a primary modality are relatively nonrobust statistically with low FI scores. Laryngoscope, 128:2094–2100, 2018
Molecular profiling of postreperfusion milieu determines acute kidney injury after liver transplantation: A prospective study
Authors: Pulitano Carlo , Ho Phong , Verran Deborah , Sandroussi Charbel , Joseph David , Bowen David G. , McCaughan Geoffrey W. , Crawford Michael , Shackel Nicholas
Published: April 2018

Acute kidney injury (AKI) after liver transplantation (LT) is a common event, but its pathogenesis remains unclear. The aim of this prospective study is to investigate the potential relationship between postreperfusion gene expression, serum mediators, and the onset of AKI after LT. Sixty‐five consecutive patients undergoing LT were included in the study. Reverse transcription polymerase chain reaction (PCR) was performed on liver biopsies. Gene expression of 23 genes involved in ischemia/reperfusion injury (IRI) was evaluated. The serum concentrations of endothelin (ET)–1 and inflammatory cytokines were analyzed. AKI after LT developed in 21 (32%) recipients (AKI group). Reverse transcription PCR of reperfusion biopsy in the AKI group showed higher expression of several genes involved in IRI compared with the non‐AKI group. Fold changes in the gene expression of ET‐1, interleukin (IL) 18, and tumor necrosis factor α (TNF‐α) were associated with creatinine peak value. AKI patients also had significantly higher ET‐1, IL18, and TNF‐α postoperative serum levels. Multivariate analysis showed that ET‐1 (odds ratio [OR], 16.7; 95% confidence interval [CI], 3.34‐83.42; P = 0.001) and IL18 (OR, 5.27; 95% CI, 0.99‐27.82, P = 0.048) serum levels on postoperative day 1 were independently predictive of AKI. Receiver operating characteristic analysis demonstrated that the combination of biomarkers ET‐1+IL18 was highly predictive of AKI (area under the receiver operating characteristic curve, 0.91; 95% CI, 0.83‐0.99). Early allograft dysfunction and chronic kidney disease stage ≥ 2 occurred more frequently in AKI patients. These results suggest that the graft itself, rather than intraoperative hemodynamic instability, plays a main role in AKI after LT. These data may have mechanistic and diagnostic implications for AKI after LT. Liver Transplantation 24 922–931 2018 AASLD.
Red and Near‐Infrared Light‐Cleavable Polymers
Authors: Zeng Xiaolong , Zhou Xuechang , Wu Si
Published: April 2018

Photocleavable polymers have attracted much attention in drug delivery, photopatterning, and controlling cell behavior. Photolysis is usually induced by UV light. However, UV light cannot penetrate deeply into biological tissue and may damage biological components. Therefore, conventional UV‐light‐cleavable polymers are problematic for deep‐tissue biomedical applications. In this feature article, red and near‐infrared light‐cleavable polymers are reviewed, and their potential applications are highlighted. The remaining challenges in the field of photocleavable polymers are discussed.
Progress on Catalytic Systems Used in Click Polymerization
Authors: Li Baixue , Huang Die , Qin Anjun , Tang Ben Zhong
Published: April 2018

Click polymerization, a powerful synthetic technique to construct polymers with unique structures and advanced functions, is of crucial importance in the areas of polymer and material sciences. A variety of click polymerizations such as azide‐alkyne, thiol‐yne, amino‐yne, and hydroxyl‐yne reactions have been established, wherein the catalytic systems play an indispensable role in realizing these highly practical reactions based on triple‐bond building blocks, as they directly influence the efficiencies of the click polymerizations and the performances of the resultant polymers. The vital employment of catalysts is reviewed and their developments from innovative discoveries to the eminent position are outlined. Moreover, the challenges and perspectives in this area are also briefly discussed.
Imaging of copper oxygenation reactions in a bubble flow
Authors: Benders Stefan , Strassl Florian , Fenger Bastian , Blümich Bernhard , Herres‐Pawlis Sonja , Küppers Markus
Published: April 2018

Reactions of gases with liquids play a crucial role in the production of many bulk chemicals. Often, the gas is bubbled into the chosen reactor. Most of the processes at the gas–liquid interface of the bubbles and in their tails are not fully understood and warrant further investigation. For this purpose, NMR imaging or Magnetic Resonance Imaging has been applied to visualize some of the processes in the bubble tail. To generate sufficient contrast, a magnetogenic gas–liquid reaction associated with a change of magnetic state, from diamagnetic to paramagnetic, was employed. In this work, a copper(I)‐based compound was oxidized to copper(II) to exploit relaxation contrast. To match the speed of the rising bubbles to the acquisition time of the spin‐echo imaging sequence, polyethylene glycol was added to increase the viscosity of the reacting solution. Images of the oxygen ingress into a static solution as well as of oxygen bubbles rising in the solution are presented. In both cases, changes in magnetism were observed, which reported the hydrodynamic processes.
Synthesis of LDPE Using Pyridineimine‐Based Nickel (II) Bromide Complexes: Effect of Catalyst Bulkiness on Thermal, Structural, and Morphological Properties
Authors: Mogheiseh Mohsen , Zohuri Gholam Hossein , Khoshsefat Mostafa
Published: April 2018

A series of pyridine‐imine [N‐N] ligands are efficiently prepared through the condensation reaction of ketone/aldehyde precursor and synthesized aniline. The ligands (Ln, n = 1–4) and corresponding nickel complexes (Cn, n = 1–4) are characterized and used for polymerization of ethylene in the presence of modified methylaluminoxane as cocatalyst. The produced low density polyethylenes show at least 21 branches per 1000 carbon atoms with Mv values up to 80.0 × 104. Aldimino‐based catalyst is more active than the analogue catalyst, although, ketimines result in polyethylene with higher Mv. Nevertheless, the product of aldimino‐based catalyst indicates the highest melting point of 132.3 °C but ketimine exhibits the highest crystallinity of 32.98% at the same polymerization conditions. Specific morphologies including smooth spherical and irregular porous particles are observed for some polymer samples. However, at high polymerization temperatures and different monomer pressures, different morphologies as well as two melting point peaks are observed in scanning electron microscopy (SEM) images and differential scanning calorimeter thermograms, respectively.
An analytic expression for the ultimate intrinsic SNR in a uniform sphere
Authors: Lee Hong‐Hsi , Sodickson Daniel K. , Lattanzi Riccardo
Published: April 2018

Purpose

The ultimate intrinsic signal‐to‐noise ratio (UISNR) is normally calculated using electrodynamic simulations with a complete basis of modes. Here, we provide an exact solution for the UISNR at the center of a dielectric sphere and assess how accurately this solution approximates UISNR away from the center.

Methods

We performed a mode analysis to determine which modes contribute to central UISNR –
. We then derived an analytic expression to calculate
and analyzed its dependence on main magnetic field strength, sample geometry, and electrical properties. We validated the proposed solution against an established method based on dyadic Green's function simulations.

Results

Only one divergence‐free mode contributes to
. The UISNR given by the exact solution matched the full simulation results for various parameter settings, whereas calculation speed was approximately 1000 times faster. We showed that the analytic expression can approximate the UISNR with <5% error at positions as much as 10–20% of the radius away from the center.

Conclusion

The proposed formula enables rapid and direct calculation of UISNR in the central region of a sphere. The resulting UISNR value may be used, for example, as an absolute reference to assess the performance of head coils with spherical phantoms.
Optimized respiratory‐resolved motion‐compensated 3D Cartesian coronary MR angiography
Authors: Correia Teresa , Ginami Giulia , Cruz Gastão , Neji Radhouene , Rashid Imran , Botnar René M. , Prieto Claudia
Published: April 2018

Purpose

To develop a robust and efficient reconstruction framework that provides high‐quality motion‐compensated respiratory‐resolved images from free‐breathing 3D whole‐heart Cartesian coronary magnetic resonance angiography (CMRA) acquisitions.

Methods

Recently, XD‐GRASP (eXtra‐Dimensional Golden‐angle RAdial Sparse Parallel MRI) was proposed to achieve 100% scan efficiency and provide respiratory‐resolved 3D radial CMRA images by exploiting sparsity in the respiratory dimension. Here, a reconstruction framework for Cartesian CMRA imaging is proposed, which provides respiratory‐resolved motion‐compensated images by incorporating 2D beat‐to‐beat translational motion information to increase sparsity in the respiratory dimension. The motion information is extracted from interleaved image navigators and is also used to compensate for 2D translational motion within each respiratory phase. The proposed Optimized Respiratory‐resolved Cartesian Coronary MR Angiography (XD‐ORCCA) method was tested on 10 healthy subjects and 2 patients with cardiovascular disease, and compared against XD‐GRASP.

Results

The proposed XD‐ORCCA provides high‐quality respiratory‐resolved images, allowing clear visualization of the right and left coronary arteries, even for irregular breathing patterns. Compared with XD‐GRASP, the proposed method improves the visibility and sharpness of both coronaries. Significant differences (p < .05) in visible vessel length and proximal vessel sharpness were found between the 2 methods. The XD‐GRASP method provides good‐quality images in the absence of intraphase motion. However, motion blurring is observed in XD‐GRASP images for respiratory phases with larger motion amplitudes and subjects with irregular breathing patterns.

Conclusion

A robust respiratory‐resolved motion‐compensated framework for Cartesian CMRA has been proposed and tested in healthy subjects and patients. The proposed XD‐ORCCA provides high‐quality images for all respiratory phases, independently of the regularity of the breathing pattern.
A novel triggering condition of event‐triggered control based on heuristic dynamic programming for discrete‐time systems
Authors: Wang Ziyang , Wei Qinglai , Liu Derong
Published: April 2018

In this paper, an event‐triggered heuristic dynamic programming algorithm for discrete‐time nonlinear systems with a novel triggering condition is studied. Different from traditional heuristic dynamic programming algorithms, the control law in this algorithm will only be updated when the triggering condition is satisfied to reduce the computational burden. Three neural networks are employed, which are model network, action network, and critic network. Model functions, control laws, and value functions are estimated using neural networks, respectively. The main contribution of this algorithm is the novel triggering condition with simpler form and fewer assumptions. Additionally, a proof of the stability for discrete‐time systems using Lyapunov technique is given. Finally, two simulations are shown to verify the effectiveness of the developed algorithm.
Clinical experience with multigene carrier panels in the reproductive setting
Authors: Terhaar Catherine , Teed Nicole , Allen Rachel , Dohany Lindsay , Settler Christina , Holland Carol , Longman Ryan E.
Published: April 2018

Objectives

Expanded carrier testing is acknowledged as an acceptable strategy for carrier testing by the American College of Obstetrics and Gynecology. Limited studies have investigated positivity rates of expanded carrier panels. We describe our experience with 3 commercial laboratory panels varying in size from 3 to 218 disorders.

Methods

We reviewed outcomes for 3 multigene carrier screening panels: trio (3 diseases), standard (23 diseases), and global (218 diseases). All panels used targeted genotype analysis of preselected mutations via next‐generation sequencing. We calculated positivity rates for each panel.

Results

Positivity rates were 7.2% for Preparent Trio, 13.2% for Preparent Standard, and 35.8% for Preparent Global. The most frequent positive results in the global panel were (in descending order): abnormal hemoglobin electrophoresis, familial Mediterranean fever, cystic fibrosis, fragile X, glucose‐6‐phosphate dehydrogenase deficiency, alpha‐thalassemia, and nonsyndromic hearing loss.

Conclusions

While genetic diseases are individually rare, they are cumulatively common. Our experience illustrates that, with a panel of 218 diseases, the likelihood of identifying a carrier can be as high as 36%. Understanding panel positivity rates is one important factor for providers when choosing the right test for their practice, setting appropriate expectations for patients, and planning for follow‐up counseling.
Fetal sex determination in twin pregnancies using cell free fetal DNA analysis
Authors: Milan Miguel , Mateu Emilia , Blesa David , Clemente‐Ciscar Monica , Simon Carlos
Published: April 2018

Objective(s)

We sought to develop an accurate sex classification method in twin pregnancies using data obtained from a standard commercial non‐invasive prenatal test.

Study Design

A total of 706 twin pregnancies were included in this retrospective analytical data study. Normalized chromosome values for chromosomes X and Y were used and adapted into a sex‐score to predict fetal sex in each fetus, and results were compared with the clinical outcome at birth.

Results

Outcome information at birth for sex chromosomes was available for 232 twin pregnancies. From these, a total of 173 twin pregnancies with a Y chromosome identified in non‐invasive pregnancy testing were used for the development of a predictive model. Global accuracy for sex classification in the testing set with 51 samples was 0.98 (95% confidence interval [0.90,0.99]), with a specificity and sensitivity of 1 (95% confidence interval [0.82,1.00]) and 0.97 (95% confidence interval [0.84,0.99]), respectively.

Conclusion

While non‐invasive prenatal testing is a screening method and confirmatory results must be obtained by ultrasound or genetic diagnosis, the sex‐score determination presented herein offers an accurate and useful approach to characterizing fetus sex in twin pregnancies in a non‐invasive manner early on in pregnancy.
Parent and teacher satisfaction with school‐based psychological reports
Authors: Rahill Stephanie A.
Published: April 2018

School psychologists spend a great deal of time translating assessment results into a psychoeducational report. The importance of creating reports that are both useful and understandable to the readers of the report while also being efficient for the school psychologist cannot be overstated. This study examines parent and teacher perceptions regarding the quality, understandability, and usefulness of school‐based psychological reports. Results of the surveys indicate that both parents and teachers perceive psychological reports as focusing more on tests and test scores as opposed to information that helps to understand the child or assists with intervention development. Strategies for upgrading reports to better meet the needs of parent and teacher readers are discussed.
Longitudinal examination of family efficacy following pediatric stem cell transplant
Authors: Tillery Rachel , Joffe Naomi E. , Mara Constance A. , Davies Stella M. , Pai Ahna L.H.
Published: April 2018

Objective

Pediatric stem cell transplant (pSCT) is emotionally demanding for families. Yet, we know little of how the family unit responds to the adversity of pSCT within the first year after transplant. Family efficacy, an indicator of family resilience, is linked to positive parent, child, and family adjustment. Better understanding the factors that promote family efficacy during this difficult time could inform modifiable intervention targets and improve child and parent adjustment. The primary objectives were to examine patterns of family efficacy beliefs and identify factors that promote or hinder family efficacy.

Methods

Ninety caregivers (71% white, 7% black, 3% Hispanic, 4% Asian, 14% multiple ethnicities) of children receiving pSCT completed demographic forms, the Psychosocial Assessment Tool, and the Filial Parental and Collective Family Efficacy Beliefs scale prior to the family's discharge, and 1, 3, 6, and 9 months post‐discharge. Latent growth curve modeling was used to examine family efficacy across time. Parent, child, and sibling distress, social support, and demographic factors served as predictors.

Results

Latent growth curve modeling demonstrated that family efficacy was stable for 9 months post pSCT discharge. Social support was positively related to family efficacy beliefs. No other variables predicted family efficacy.

Conclusion

Most families perceive themselves as resilient following pSCT. Social relationships and support are critical in maintaining a family's sense of efficacy during the arduous pSCT course.