bluuebunny/crossref_metadata_2025_split huggingface dataset:
5‐exo versus 6‐endo Thiyl‐Radical Cyclizations in Organic Synthesis
Authors: McCourt Ruairí , Scanlan Eoin M. 
Published: October 2019

AbstractSince the discovery of the radical mediated thiol‐ene and thiol‐yne reactions, these reactions have been employed in an intramolecular manner for the synthesis of sulfur‐containing heterocycles. Although closely related on a mechanistic basis, the thiol‐ene and thiol‐yne cyclization can differ greatly in regioselectivity and product distribution, with the thiol‐ene process being more predictable and thus attracting greater utilization. Herein, we review intramolecular thiyl‐radical addition reactions and the factors leading to the observed regioselectivity in examples in which both the 5‐exo and 6‐endo mode of cyclization are feasible. We highlight the applications of these important reactions for organic synthesis in the recent literature.
Experimental study of the synergistic effect and network regulation mechanisms of an applied combination of BMP‐2, VEGF, and TGF‐β1 on osteogenic differentiation
Authors: Wang Zhihao , Sun Jian , Li Yali , Chen Chen , Xu Yaoxiang , Zang Xiaolong , Li Li , Meng Kun 
Published: October 2019

AbstractThe study aimed to explore the osteogenic effect induced by the combined use of bone morphogenetic protein‐2 (BMP‐2), vascular endothelial growth factor (VEGF), and transforming growth factor‐β1 (TGF‐β1), attain the best combination for osteogenic quality and efficiency, and explore the network regulation mechanisms of induced osteogenesis. MC3T3‐E1 cells were cultured in vitro, and BMP‐2, VEGF, and TGF β1 were added to osteogenic induction mediums in different combinations to conduct experiments. At 7 and 14 days, the alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining of the applied BMP‐2 and VEGF combination were deeper and the quantitative analysis were higher than those of the other groups. After optimizing the time–effect relationship of the combined application, with BMP‐2, VEGF, and TGF‐β1 adding in the early stage and BMP‐2 and VEGF adding in the late, the ALP and ARS staining of these groups were deeper and the quantitative analyses were meaningfully higher than the BMP‐2 and VEGF combination group at 7 and 14 days. The expression of the RUNX2 gene and the Smad1 signaling pathway in the optimized combination group was also significantly higher. The results demonstrate that the combination of BMP‐2, VEGF, and TGF‐β1 applied according to the time–effect relationship can significantly promote osteogenic differentiation mainly through the classical BMP‐receptor‐Smad signal pathway.
Colon cancer therapy by focusing on colon cancer stem cells and their tumor microenvironment
Authors: Jahanafrooz Zohreh , Mosafer Jaffar , Akbari Morteza , Hashemzaei Mahmoud , Mokhtarzadeh Ahad , Baradaran Behzad 
Published: October 2019

AbstractDespite many advances and optimization in colon cancer treatment, tumor recurrence and metastases make the development of new therapies necessary. Colon cancer stem cells (CCSCs) are considered as the main triggering factor of cancer progression, recurrence, and metastasis. CCSCs as a result of accumulated genetic and epigenetic alterations and also complex interconnection with the tumor microenvironment (TME) can evolve and convert to full malignant cells. Mounting evidence suggests that in cancer therapy both CCSCs and non‐CCSCs in TME have to be regarded to break through the limitation of current therapies. In this regard, stem cell capabilities of some non‐CCSCs may arise inside the TME condition. Therefore, a deep knowledge of regulatory mechanisms, heterogeneity, specific markers, and signaling pathways of CCSCs and their interconnection with TME components is needed to improve the treatment of colorectal cancer and the patient's life quality. In this review, we address current different targeted therapeutic options that target cell surface markers and signaling pathways of CCSCs and other components of TME. Current challenges and future perspectives of colon cancer personalized therapy are also provided here. Taken together, based on the deep understanding of biology of CCSCs and using three‐dimensional culture technologies, it can be possible to reach successful colon cancer eradication and improvise combination targeted therapies against CCSCs and TME.
Phenolic composition of Tempranillo Blanco (Vitis vinifera L.) grapes and wines after biostimulation via a foliar seaweed application
Authors: Gutiérrez‐Gamboa Gastón , Garde‐Cerdán Teresa , Martínez‐Lapuente Leticia , Costa Bianca Souza‐da , Rubio‐Bretón Pilar , Pérez‐Álvarez Eva P 
Published: October 2019

AbstractBACKGROUNDSeaweeds are defined as novel elicitors in many crops, allowing the synthesis of secondary metabolites to be triggered in different plant tissues. Currently, the phenolic composition of Tempranillo Blanco grapes and wines is unreported. The present study aimed to investigate the effects of an Ascophyllum nodosum seaweed extract applied to Tempranillo Blanco grapevines, at low (Ld) and high (Hd) dosages, on grape and wine phenolic compounds during two consecutive seasons (2017–2018).RESULTSThe results obtained showed that catechin was the most abundant phenolic compound in Tempranillo Blanco grapes and wines. Season affected the weight of 100 berries and some enological parameters. Catechin and flavonols concentrations in grapes were increased after Hd application to grapevines, independently of season. The concentration of hydroxycinnamic and hydroxybenzoic acids in wines was affected by vintage, probably as a result of oxidation reactions, as well as pinking phenomena, whereas the stilbenes content in wines was conditioned by the affect of cryptogamic diseases in grapes.CONCLUSIONSeaweeds might act as an elicitor of several phenolic compounds in grapes, enhancing the content of some phenolic compounds in wines. © 2019 Society of Chemical Industry
The concentration of the cleaved suPAR forms in pre‐ and postoperative plasma samples improves the prediction of survival in colorectal cancer: A nationwide multicenter validation and discovery study
Authors: Rolff Hans C. , Christensen Ib J. , Svendsen Lars B. , Wilhelmsen Michael , Lund Ida K. , Thurison Tine , Høyer‐Hansen Gunilla , Illemann Martin , Nielsen Hans J. ,   on behalf of the Danish Collaborative Research Group on Colorectal Cancer
Published: October 2019

AbstractBackground and ObjectivesThe aim was to evaluate the prognostic biomarker potential of the soluble urokinase‐type plasminogen activator receptor (suPAR) in plasma samples collected pre‐ and postoperatively from patients resected for colorectal cancer (CRC).MethodsPatients with CRC were recruited prospectively at six centers from 2006 to 2008. Preoperative plasma samples were available from 494 patients and from 328 of these patients at 6 months postoperatively. Determinations of intact soluble uPAR (suPAR) suPAR(I‐III) and the cleaved forms suPAR(I‐III) + (II‐III) and uPAR(I) were performed. Clinical data were retrieved retrospectively.ResultsIn a multivariable model based on preoperative plasma samples suPAR(I‐III) + (II‐III) and uPAR(I) showed an independent statistically significant association to long term survival. When including the change in biomarker level between the pre‐ and postoperatively samples the hazard ratios were 3.06 (95% confidence interval [CI], 1.78‐5.28; P < .0001) and 2.24 (95% CI, 1.59‐3.16; P < .0001) for suPAR(I‐III) + (II‐III) and uPAR(I), respectively. A one‐unit decrease in biomarker levels between the pre‐ and postoperative levels resulted in a 55% and 34% reduction in the risk estimate of death for suPAR(I‐III) + (II‐III) and uPAR(I), respectively.ConclusionThis study validates previously findings regarding the prognostic significance of suPAR in preoperative samples. The inclusion of postoperative samples added further prognostic information.
Carotid Artery Corrected Flow Time and Respiratory Variations of Peak Blood Flow Velocity for Prediction of Hypotension After Induction of General Anesthesia in Adult Patients Undergoing Elective Surgery: A Prospective Observational Study
Authors: Maitra Souvik , Baidya Dalim K. , Anand Rahul K. , Subramanium Rajeshwari , Bhattacharjee Sulagna 
Published: October 2019

ObjectivesHypotension is common after induction of general anesthesia, and intraoperative hypotension is associated with postoperative end‐organ injury such as acute kidney injury and myocardial ischemia. This study was designed to determine the utility of the carotid corrected flow time (cFT) and carotid artery peak blood flow velocity variation (ðVpeak) for prediction of hypotension after induction of general anesthesia.MethodsAdult patients (n = 112) undergoing any elective surgery under general anesthesia who fasted for at least 6 to 8 hours were recruited in this prospective observational study. The common carotid artery cFT and ðVpeak were measured with ultrasound 10 minutes before induction of general anesthesia. After that, general anesthesia with propofol was used, and hemodynamic data were collected until 3 minutes after induction of anesthesia.ResultsThe carotid cFT was significantly correlated with percentages of the fall in the systolic blood pressure at 2 minutes (P < .0001) and 3 minutes (P < .0001) and percentages of the fall in the mean arterial pressure at 1 minute (P = .0006), 2 minutes (P < .0001), and 3 minutes (P < .0001). The cFT was a predictor of hypotension after induction of general anesthesia, with an area under the receiver operating characteristic curve of 0.91. The best cutoff value obtained from this study was 330.2 milliseconds or less, which predicted postinduction hypotension with sensitivity and specificity of 85.7% and 96.8%, respectively. The ðVpeak was an inferior predictor of postinduction hypotension, with an area under the receiver operating characteristic curve of 0.68. The optimum cutoff value was 18.8%, with sensitivity and specificity of 61.9% and 67.4%.ConclusionsThe cFT measured in the common carotid artery is a reasonable predictor of hypotension after induction of general anesthesia in American Society of Anesthesiologists physical status I and II patients. Further studies are required to identify its role in high‐risk patients such as older groups and patients with cardiovascular diseases and also to identify interobserver and intraobserver variability of cFT and ðVpeak measurements.
Antenna alignment by using computer vision technology
Authors: Chen Biao , Liu Yuzhe 
Published: October 2019

AbstractAn automatic alignment approach is proposed for tracking unmanned aerial vehicle (UAV) antennas by using computer vision technology. In this approach, UAV carries a low‐gain omnidirectional antenna and a ground station uses high gain directional antenna which can be driven by a pan‐tilt to point to UAV's antenna. A camera is bound together with the antenna and a computer is employed to recognize the video and control motion of the pan‐tilt, so as to move the image of UAV's antenna toward the center of the whole picture. If the distance between center of UAV image and center of the picture is kept within a few pixels, then the antennas are aligned. Performance analysis and experiment results are given, showing that the proposed antenna autoalignment approach can achieve accurate alignment of the antennas with an angle error of less than 1°.
DiGeorge syndrome chromosome region deletion and duplication: Prenatal genotype‐phenotype variability in fetal ultrasound and MRI
Authors: Tramontana Allessandra , Hartmann Beda , Hafner Erich 
Published: October 2019

AbstractObjectiveThe aim of the study was to assess genotype‐phenotype correlation of prenatally diagnosed fetal DGS and dup22q11 syndrome by fetal molecular genetic analysis, fetal ultrasound, and/or MRI.MethodsIn this retrospective consecutive case series, pregnant women were screened for fetal anomalies during a period of 10 years. Fetal genotype was assessed in 72 cases upon the occurrence of five prenatal fetal phenotypic features: cardiac anomalies, hypo/aplastic thymus, craniofacial malformations, urinary abnormalities, or IUGR; genotype‐phenotype correlation was tested to potentially improve prenatal diagnosis of fetal DGS and dup22q11 syndrome.ResultsFetal genotypes of deletions or duplications in proximal clusters of LCR22s (A‐B) were associated with fetal cardiac anomalies in combination with hypo/aplastic thymus and craniofacial malformations, suggesting a correlation with deleted HIRA. TOF associated with aplastic thymus in combination with renal defects indicated a relevant correlation with TBX1 deletion. Deletions in central LCR22s (B‐D) with the loss of CRKL supposed a trend of genotype‐phenotype correlation with fetal urinary abnormalities.ConclusionGenotype‐phenotype correlation might improve prenatal diagnosis of fetal DGS and dup22q11 syndrome. Hence, prenatal screening and counseling is highly enhanced by a combination of fetal molecular genetic analysis, fetal ultrasound, and/or MRI. The implications of these findings remain to be explored.
Buoyancy‐driven entrainment in dry thermals
Authors: McKim Brett , Jeevanjee Nadir , Lecoanet Daniel 
Published: October 2019

AbstractOver 50 years ago it was proposed that dry thermals entrain because of buoyancy (via a constraint which requires an increase in the radius a). However, this runs counter to the scaling arguments commonly used to derive the entrainment rate, which rely on either the self‐similarity or a turbulent entrainment hypothesis. The assumption of turbulence‐driven entrainment has been investigated and it has been found that the entrainment efficiency e varies by less than 20% between laminar (Re=630) and turbulent (Re=6300) thermals. This motivated us to utilize the argument of buoyancy‐controlled entrainment in addition to the thermal's vertical momentum equation to build a model for thermal dynamics which does not invoke turbulence or self‐similarity. We derive simple expressions for the thermals' kinematic properties and their fractional entrainment rate ϵ and find close quantitative agreement with the values in direct numerical simulations. In particular, our expression for entrainment rate is consistent with the parametrization ϵ∼B/w2, for Archimedean buoyancy B and vertical velocity w. We also directly validate the role of buoyancy‐driven entrainment by running simulations where gravity is turned off midway through a thermal's rise. The entrainment efficiency e is observed to drop to less than one third of its original value in both the laminar and turbulent cases when g=0, affirming the central role of buoyancy in entrainment for dry thermals.
Generalized relativistic effective core potentials for superheavy elements
Authors: Mosyagin Nikolai S. , Zaitsevskii Andrei V. , Titov Anatoly V. 
Published: October 2019

AbstractThe generalized relativistic effective core potentials (GRECPs) for calculations of electronic structure and physical‐chemical properties of compounds containing superheavy elements (Z ≥ 104) are presented. Features of accounting for the finite nuclear size effects which are unusually large for superheavy elements are discussed in details. Accuracy of the GRECPs is analyzed in atomic calculations compared to all‐electron studies with the Dirac‐Coulomb‐Breit Hamiltonian. Applications of the GRECP method in molecular and cluster calculations are surveyed.
Assessment of reliability of EN 1992‐1‐1 variable strut inclination method of shear design provisions for stirrup failure
Authors: Olalusi Oladimeji B. , Viljoen Celeste 
Published: October 2019

AbstractThe best estimate shear strength predictions of the operational EN 1992‐1‐1 (EC2) variable strut inclination method (VSIM) have been shown to underestimate shear capacity at low stirrup quantities. Conversely, the model overestimates shear capacity at high stirrup quantities (Cladera and Mari, 2007; Olalusi and Viljoen, 2019). Sufficient safety performance of the design formulation should be confirmed at high levels of stirrup reinforcement, and over conservatism at low stirrup reinforcement is not ideal. This contribution assesses the consistency and uniformity of the reliability index of EC2 shear design formulation over the range of practical design situations. Prediction model uncertainty is an important parameter in the assessment (Olalusi and Viljoen, 2019). The principal reliability assessment was performed using as general probabilistic model (GPM), the probabilistic representation of the modified compression field theory (MCFT) as implemented in analysis program Response 2000 (R2k), which was shown to provide the most accurate estimates of shear capacity (Bentz, 2000). This was validated by means of a similar reliability analysis using the compression chord capacity model (CCC) as GPM. The outcome of EC2 reliability analysis indicated uneconomically high reliability at low levels of shear reinforcement, high concrete strength and large beam depth, and actively reducing reliability with increased levels of shear reinforcement, reduced concrete strength and reduced beam depth for both rectangular and I‐shaped beam cross‐sections. Reliability indices of all the test sections investigated meet the target reliability requirements for Reliability Class 2 structures prescribed by basis of design standards SANS 10160 and EN 1990, for the design range considered.
Architecting systems‐of‐systems and their constituents: A case study applying Industry 4.0 in the construction domain
Authors: Axelsson Jakob , Fröberg Joakim , Eriksson Peter 
Published: October 2019

AbstractThe development of system‐of‐systems (SoS) requires a continuous interplay between design decisions on the SoS level and those on the level of its constituent systems (CS), which often preexist and need to be adapted as the SoS evolves. This involves not only preparing the CS to participate in a particular SoS, but also designing the CS architecture to make it easily adaptable to a future SoS context. The problem is in part addressed in an emerging SoS framework in the manufacturing domain called Industry 4.0. It focuses on connected and digitalized production with the ambition of increasing flexibility and efficiency. This paper investigates how Industry 4.0 standards can be used in an SoS context to make CS more flexible and adaptive, and evaluates their usefulness outside manufacturing. The study is based on a case from the construction domain, for which a generic SoS architecture is developed. Several extensions and adaptations of Industry 4.0 are suggested, including specifications of ontologies for missions and workflows.
Optimum placement of supplementary viscous dampers for seismic rehabilitation of steel frames considering soil–structure interaction
Authors: Sarcheshmehpour Mohammad , Estekanchi Homayoon E. , Ghannad Mohammad Ali 
Published: October 2019

SummaryIn this paper, the significance of soil–structure interaction (SSI) in optimal placement of viscous dampers in steel frames is studied. Optimal placement of dampers is determined with the purpose of achieving performance objectives at three hazard levels using genetic algorithm optimization. Endurance time method is used for seismic nonlinear response analysis of the fixed‐base and SSI included frames. The soil beneath the structures is considered as a homogeneous elastic half‐space, and the soil–structure systems are modeled by the substructure method. Results indicate that at low excitation intensities, consideration of SSI results in maximum drift ratio reduction at all stories of the frames. At higher intensity levels, more drift is observed in the upper stories of the soil–structure systems in comparison with the fixed‐base frames. Higher damping in the upper stories is required to optimally rehabilitate soil–structure systems as compared with the corresponding fixed‐base ones. In most of the frames, SSI leads to the reduction of total required damping. However, the optimal damper placement based on the analysis of fixed‐base frames can be unconservative due to changes in damping distribution patterns.
Suppressing Arc Development by Arc‐Extinguishing and Lightning‐Protection Device
Authors: Yan Renbao , Wang Jufeng , Nie Yonghui , Li Zijian 
Published: October 2019

When a transmission line is struck by lightning, or a power‐frequency flashover of insulator strings occurs, arc‐extinguishing and lightning‐protection devices can effectively save the insulators from cauterization caused by power‐frequency arcs and can quickly break the transient arc after a device is struck by an impulse flashover. The working principle of arc‐extinguishing and lightning‐protection devices is that the device can instantly produce a jet airflow and the arc will be extinguished in its initial phase itself; thus, the arc is suppressed thoroughly. In other words, the air blast extinguishes the arc when its current is only a few amperes, and, ideally, there is no arc at all. The earlier the jet airflow acts on the arc, the better the arc‐extinguishing effect. The proposed theory of the arc‐extinguishing and lightning‐protection device is experimentally verified. Photos from a high‐speed camera demonstrate the thorough inhibition effect of the high‐speed jet airflow on the arc. The time during which the arc is extinguished is about 7 ms, and the arc is not regenerated. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
The work after “It's too late” (to prevent dangerous climate change)
Authors: Moser Susanne C. 
Published: October 2019

AbstractThe fact that the question “Is it too late (to prevent dangerous climate change”)? is being debated in serious science circles constitutes a culturally significant moment. This article does not offer a simplistic answer to “is it too late – or not?”, but explores the uncomfortable space of denying neither endings nor possibilities. In so doing, it asks readers to witness and engage with what appears to be a serious psychological and cultural struggle within ourselves, now publicly visible, over what and how to confront endings, what kind of hope to sustain, and how to be and act in the face of these accumulating apocalyptic (i.e., revelatory) facts. The article sketches the variety of endings being faced at this time and the psychological responses to them. It then outlines the political, policy, and practical work, as well as the deeper, underlying socio‐cultural and psychological work, that the paradoxical tension between endings and possibilities demands.This article is categorized under:

Perceptions, Behavior, and Communication of Climate Change > Communication
Is it too late to prevent systemic danger to the world's poor?
Authors: Farbotko Carol 
Published: October 2019

AbstractTo answer the question “is it too late to stop dangerous climate change?” requires systemic thinking. An experiment named ‘climate risk disclosure’ is currently underway in the global financial industry, one that is seeking to stabilize the climate‐finance meta‐system. This meta‐system is in danger of meta‐crisis, but addressing this risk in itself is a systemic danger to the world's poor, to the extent that the climate‐finance risk calculus does not adequately account for social risk. The global poor now face being systemically excluded from having their interests measured and managed in the climate‐finance meta‐system. Already vulnerable groups, at risk from poverty, climate change impacts, political unrest, and other social ills, are at risk of being even further marginalized. The systemic embedding of social exclusion is a largely unrecognized risk in work toward maintaining climate‐finance meta‐system stability. The question of preventing dangerous climate change, then, may be not so much a question of ‘when?,’ but of how to reduce the dangers arising from systemic social marginalization and compounding vulnerabilities along with systemically reducing carbon emissions. Perhaps it is not loo late to stop climate danger, but without a specific focus on social risk in the meta‐system this may only be true for those who already enjoy the fruits of global financial stability.This article is categorized under:

Social Status of Climate Change Knowledge > Knowledge and Practice