bluuebunny/crossref_metadata_2025_split huggingface dataset:
Averaging over spatiotemporal heterogeneity substantially biases evapotranspiration rates in a mechanistic large-scale land evaporation model
Authors: Rouholahnejad Freund Elham , Zappa Massimiliano , Kirchner James W. 
Published: October 2020

Abstract. Evapotranspiration (ET) influences land–climate interactions, regulates the
hydrological cycle, and contributes to the Earth's energy balance. Due to
its feedback to large-scale hydrological processes and its impact on
atmospheric dynamics, ET is one of the drivers of droughts and heatwaves.
Existing land surface models differ substantially, both in their estimates
of current ET fluxes and in their projections of how ET will evolve in the
future. Any bias in estimated ET fluxes will affect the partitioning between sensible and latent heat and thus alter model predictions of temperature and precipitation. One potential source of bias is the so-called “aggregation bias” that arises whenever nonlinear processes, such as those that regulate ET fluxes, are modeled using averages of heterogeneous inputs. Here we demonstrate a general mathematical approach to quantifying and correcting for this aggregation bias, using the GLEAM land evaporation model as a relatively simple example. We demonstrate that this aggregation bias can lead to substantial overestimates in ET fluxes in a typical large-scale land surface model when sub-grid heterogeneities in land surface properties are averaged out. Using Switzerland as a test case, we examine the scale dependence of this aggregation bias and show that it can lead to an average overestimation of daily ET fluxes by as much as 10 % across the whole country (calculated as the median of the daily bias over the growing season). We show how our approach can be used to identify the dominant drivers of aggregation bias and to estimate sub-grid closure relationships that can correct for aggregation biases in ET estimates, without explicitly representing sub-grid heterogeneities in large-scale land surface models.
From Defiant Egoist to Submissive Citizen: Is There a Bridge? Why the Hell Is There a Bridge?
Authors: Long Roderick T. 
Published: October 2020

AbstractThe author reviews Foundations of a Free Society: Reflections on Ayn Rand’s Political Philosophy, edited by Gregory Salmieri and Robert Mayhew, and finds it to be a rich and provocative anthology. However, the author is unpersuaded by the arguments, from a number of the contributors, for separating the prohibition on initiatory force as an ethical principle, from individual rights as a political principle—a separation that, on the ethical side, unduly discards the Aristotelean ethical approach with which Randian ethics claims affiliation, and on the political side, is employed to ground an unconvincing case for the legitimacy of the state.
Application of Platelet Rich Fibrin, Platelet Rich Plasma, Plasma Rich Growth Factors in Different Fields of Dentistry: An Overview
Authors: Singh Geetanjali , Kumari Bhawna , Grover Harangad Singh , Mahajan Akriti , Jabeen Farhat , Kumar Ajay 
Published: October 2020

A huge number of studies have demonstrated that platelet-rich preparations applied to surgical sites, injuries, or wounds are effective way to promote soft tissue healing and bone growth. The potential use of platelet rich preparations like Platelet - rich plasma and Platelet - rich fibrin are new boon to dentistry termed under the general acronyms PRP (Platelet-Rich Plasma) or PRF (Platelet-Rich Fibrin), is an important current transversal field of research across many fundamental and clinical disciplines.The third important is PRGF. Plasma Rich in Growth Factor (or PRGF) is a type of plasma enriched of proteins and circulating growth factors able to aid the bone and soft tissue regeneration. PRGF includes plasma proteins and coagulative factors and is then more valuable compared to PRP. There are many scientific literature which cover one or other concise aspect of platelet rich preparation. This review aims at covering all basic definitions, key element, history, preparation, differences between PRF and PRP and applications in a simplified manner.
An Efficient Method for The Synthesis of Dihydropyridine by Hantzsch Reaction with Fe/SiO2 Nano Heterogeneous Catalysts
Authors: Rahman Ateeq , Nehemia P. N. , Nyambe Moola M. 
Published: October 2020

An efficient method for the synthesis of dihydropyridines (DHPs) by Hantzsch reaction with Fe/SiO2 heterogeneous catalysts was developed. The Fe/SiO2 catalysts was prepared by impregnation method. The catalysts were characterized by IR and SEM instruments. The SEM results indicated that Fe/SiO2 nano spheres were formed. The reaction procedure involved reaction of aldehyde, ethyl acetoacetate (EAA), ammonium acetate (NH4OAc) and ethanol under reflux. The study was focused on optimizing reactions conditions: Standardization of catalyst, substrate of study and solvent study. In order to identify the best active catalysts, five different ratios of catalyst were synthesized and evaluated for the title reaction under similar conditions. To standardize the active catalysts, different temperature conditions (i.e. room temperature, 60 ºC and 80 ºC) as well as catalysts amounts were evaluated. Under these established conditions, 2.5% Fe/SiO2 was the best active catalysts that resulted. Benzaldehyde and p-anisaldehyde were used to study the effect of having various substrates on the conversion and reaction time, especially the substituted aldehydes. The best results were obtained by reacting p-anisaldehyde with EAA, NH4OAc and ethanol at 60 ºC with 0.3 grams of 2.5% Fe/SiO2 heterogeneous catalysts. Thin Layer Chromatography (TLC) monitoring of the reaction mixture showed no selectivity at high temperatures (80 ºC) with 15% Fe/SiO2. Standardization of solvent study was executed with two solvents, ethanol and acetonitrile. The product dihydropyridines were analyzed using gas chromatography-mass spectrometry (GC-MS). The melting points of the products were compared with authentic samples reported in the literature. Hence, the Fe/SiO2 catalysts is eco-friendly and economically developed for the title reaction. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Natural Clay of Pasaman Barat Enriched by CaO of Chicken Eggshells as Catalyst for Biodiesel Production
Authors: Syukri Syukri , Septioga Kevin , Arief Syukri , Putri Yulia Eka , Efdi Mai , Septiani Upita 
Published: October 2020

This study uses broiler chicken eggshells to enhance catalytic activity of clay obtained from Pasaman Barat (West Sumatra, Indonesia) in lab-scale biodiesel production. The eggshell is a source of calcium oxide (CaO) which operates as a catalyst when mixed with the clay (Ca-Clay). Two other catalysts were also prepared as comparisons by 1) heating the clay at 800 oC for 6 hours (P-Clay), 2) mixing the P-Clay with KOH (K-Clay). An X-ray Fluorescence (XRF) showed the elemental composition of Ca-Clay contained Ca, Si, Al, and Fe. An X-ray Diffraction (XRD) showed the formation of highly crystalline CaO in the Ca-Clay with the main peak at 2θ = 37.27o. The Fourier Transform Infra Red (FTIR) spectrum showed an absorption peak in the range of 700-900 cm-1 indicating Ca-O stretching demonstrating successful incorporation of the CaO into the clay. The catalytic activity test showed the Ca-Clay had a higher catalytic performance than P-Clay and K-Clay in terms of the yield of biodiesel produced (73%). Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Synthesis of Ziegler-Natta Catalyst using Malaysian Ilmenite Derived TiCl4 via Recrystallization Method: A Statistical Approach
Authors: Udayakumar Sanjith , Ibrahim Najwa , Chien Chan Yong , Shaik Abdul Wahab Shaikh Abdul Rahman , Mohd Noor Ahmad Fauzi , Ramakrishnan Sivakumar 
Published: October 2020

In the current study, Ziegler-Natta (Z-N) catalyst was synthesized via recrystallization method using MgCl2 as a support, AlCl3 as an activator and TiCl4 as a transition metal source. The TiCl4 used in the study was derived from Malaysian ilmenite through a sequential pyrometallurgical and hydrometallurgical process of ilmenite concentrate conversion to TiCl4. The recrystallization method of synthesis of the heterogeneous Z-N catalyst was studied by varying the synthesis parameters, such as the combined amount of MgCl2 and AlCl3, temperature, and amount of TiCl4, using statistical design of experiments. The investigation aimed at determining the best conditions for synthesizing the heterogeneous Z-N catalyst. The synthesis conditions posed a significant influence on the Ti content present in the catalyst product. The morphological and elemental analysis of SEM-EDX showed good spherical nature of the prepared catalysts. The XRD phase analysis detected the peaks of MgCl2, MgCl2-Ethanol, MgCl2/TiClx, and TiO2. The IR spectra confirmed the presence of the Mg-Cl bond at 1635 cm−1 and Ti-Cl bonds at 602 cm-1 and 498 cm-1. The produced catalyst contained a small amount of TiO2, which could be due to the seepage of moisture during the analysis or storage of the sample. The most favourable combination of the studied parameters was determined based on the Ti content in the catalyst product. Therefore, the best conditions for synthesizing the heterogeneous Z-N catalyst with high Ti content (181.1 mg/L) was at a combined amount of 2 g of MgCl2 for 6 g of AlCl3, crystallization temperature of 80 °C, and 2 mL dosage of TiCl4. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Production of Acetaldehyde via Oxidative Dehydrogenation of Ethanol over AgLi/SiO2 Catalysts
Authors: Mukda Narawich , Autthanit Chaowat , Praserthdam Piyasan , Jongsomjit Bunjerd 
Published: October 2020

Three AgLi/SiO2 catalysts containing different types of silica supports [small particle size (SPS), medium particle size (MPS) and large particle size (LPS)] were prepared by incipient wetness co-impregnation techniques and tested in oxidative dehydrogenation of ethanol into acetaldehyde. The catalysts were characterized and evaluated by various characterization techniques (e.g. XRD, N2 physisorption, SEM-EDX, UV-Visible spectroscopy, H2-TPR, and CO2-TPD). This study reveals that the catalyst with the best performance is AgLi/SiO2-LPS with a yield in acetaldehyde of 76.8% at 300 °C. The results obtained with the tested catalysts are discussed, and the reasons of performance improvement caused by the presence of the dispersion of active components, the interaction between active components and silica supports, the textural properties of catalysts and reducibility, are raised. Besides, the cooperation of redox properties (Agnδ+ cluster and Ag0) and weak basic density played a pivotal role in promoting the formation of acetaldehyde from ethanol oxidative dehydrogenation. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
SARS‐CoV‐2 RBD Neutralizing Antibody Induction is Enhanced by Particulate Vaccination
Authors: Huang Wei‐Chiao , Zhou Shiqi , He Xuedan , Chiem Kevin , Mabrouk Moustafa T. , Nissly Ruth H. , Bird Ian M. , Strauss Mike , Sambhara Suryaprakash , Ortega Joaquin , Wohlfert Elizabeth A. , Martinez‐Sobrido Luis , Kuchipudi Suresh V. , Davidson Bruce A. , Lovell Jonathan F. 
Published: October 2020

AbstractThe receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike protein is a candidate vaccine antigen that binds angiotensin‐converting enzyme 2 (ACE2), leading to virus entry. Here, it is shown that rapid conversion of recombinant RBD into particulate form via admixing with liposomes containing cobalt‐porphyrin‐phospholipid (CoPoP) potently enhances the functional antibody response. Antigen binding via His‐tag insertion into the CoPoP bilayer results in a serum‐stable and conformationally intact display of the RBD on the liposome surface. Compared to other vaccine formulations, immunization using CoPoP liposomes admixed with recombinant RBD induces multiple orders of magnitude higher levels of antibody titers in mice that neutralize pseudovirus cell entry, block RBD interaction with ACE2, and inhibit live virus replication. Enhanced immunogenicity can be accounted for by greater RBD uptake into antigen‐presenting cells in particulate form and improved immune cell infiltration in draining lymph nodes. QS‐21 inclusion in the liposomes results in an enhanced antigen‐specific polyfunctional T cell response. In mice, high dose immunization results in minimal local reactogenicity, is well‐tolerated, and does not elevate serum cobalt levels. Taken together, these results confirm that particulate presentation strategies for the RBD immunogen should be considered for inducing strongly neutralizing antibody responses against SARS‐CoV‐2.
Self‐Synthesizing Nanorods from Dynamic Combinatorial Libraries against Drug Resistant Cancer
Authors: Cao Yu , Yang Jian , Eichin Dominik , Zhao Fangzhe , Qi Dawei , Kahari Laura , Jia Chunman , Peurla Markus , Rosenholm Jessica M. , Zhao Zhao , Jalkanen Sirpa , Li Jianwei 
Published: October 2020

AbstractMolecular self‐assembly has been widely used to develop nanocarriers for drug delivery. However, most of them have unsatisfactory drug loading capacity (DLC) and the dilemma between stimuli‐responsiveness and stability, stagnating their translational process. Herein, we overcame these drawbacks using dynamic combinatorial chemistry. A carrier molecule was spontaneously and quantitatively synthesized, aided by co‐self‐assembly with a template molecule and an anti‐cancer drug doxorubicin (DOX) from a dynamic combinatorial library that was operated by disulfide exchange under thermodynamic control. The highly selective synthesis guaranteed a stable yet pH‐ and redox‐ responsive nanocarrier with a maximized DLC of 40.1 % and an enhanced drug potency to fight DOX resistance in vitro and in vivo. Our findings suggested that harnessing the interplay between synthesis and self‐assembly in complex chemical systems could yield functional nanomaterials for advanced applications.
Backbone‐Bridging Promotes Diversity in Heteroleptic Cages
Authors: Wu Kai , Zhang Bo , Drechsler Christoph , Holstein Julian J. , Clever Guido H. 
Published: October 2020

AbstractThe combination of shape‐complementary bis‐monodentate ligands LA and LB with PdII cations yields heteroleptic cages cis‐[Pd2LA2LB2] by self‐sorting. Herein, we report how such assemblies can be diversified by introduction of covalent backbone bridges between two LA units. Together with solvent and guest effects, the flexibility of these linkers can modulate nuclearity, topology, and number of cavities in a family of four structurally diverse assemblies. Ligand LA1, with flexible linker, reacts in CH3CN with its LB counterpart to a tetranuclear dimer D1. In DMSO, however, a trinuclear pseudo‐tetrahedron T1 is formed. The product of LA2, with rigid linker, looks similar to D1, but with a rotated ligand arrangement. In presence of an anionic guest, this dimer D2 transforms and a hexanuclear prismatic barrel P2 crystallizes. We demonstrate how controlling a ligand's coordination mode can trigger structural differentiation and increase complexity in metallo‐supramolecular assembly.
Fish species redundancy in estuaries: A major conservation concern in temperate estuaries under global change pressures
Authors: Whitfield Alan K. , Harrison Trevor D. 
Published: October 2020

Abstract

Fish assemblages in estuaries have a much lower species richness (number of taxa) when compared with the combined numbers of freshwater and marine species from adjacent aquatic ecosystems. This is primarily because of the relatively harsh and fluctuating physico‐chemical conditions in estuaries compared with the more stable freshwater and marine environments.
A comprehensive fish survey of estuaries in South Africa is used as a basis to determine fish species richness in subtropical, warm temperate, and cool temperate systems along the coast, and to assess the degree of redundancy in the different biogeographic regions.
In general, only one or two species belonging to each of the detritivorous, piscivorous, zoobenthivorous, and zooplanktivorous fish guilds are numerically well represented in the larger cool temperate estuaries, but between four and 10 species in each of these guilds are usually recorded in the larger subtropical estuaries.
Although the overall low redundancy of fish species groups in estuaries has already been formally recognized in the literature, this short note highlights the sensitivity of certain trophic guilds in temperate South African estuaries to any form of redundancy, a characteristic that may be equally applicable, based on declining species richness with increasing latitude, to temperate estuaries in other parts of the world.
Coniferyl Alcohol Radical Detection by the Dirigent Protein AtDIR6 Monitored by EPR
Authors: Modolo Camille , Ren Lu , Besson Eric , Robert Viviane , Gastaldi Stéphane , Rousselot‐Pailley Pierre , Tron Thierry 
Published: October 2020

AbstractPlant dirigent proteins (DIRs) control the stereoselectivity of the monolignol coniferyl alcohol radical coupling. The main mechanistic hypothesis on this chemo‐ and stereoselective reaction invokes a binding of coniferyl alcohol radical substrates in the dirigent protein active site so that only one enantiomeric form can be produced. We have studied the influence of the Arabidopsis thaliana AtDIR6 protein on the transient coniferyl alcohol radical by EPR. Herein, we show that AtDIR6 stabilizes coniferyl alcohol radicals prior to directing their coupling towards the formation of (−)‐pinoresinol.
Fluorescent Peptide Biosensor for Probing CDK6 Kinase Activity in Lung Cancer Cell Extracts
Authors: Soamalala Jessica , Diot Sebastien , Pellerano Morgan , Blanquart Christophe , Galibert Mathieu , Jullian Magali , Puget Karine , Morris May C. 
Published: October 2020

AbstractCDK6 kinase regulates cell‐cycle progression in G1, together with CDK4, but has cell‐, tissue‐ and developmentally distinct functions associated with transcription, angiogenesis and metabolism. Although CDK6 makes an attractive cancer biomarker and target, there are no means of assessing its activity in a complex environment. In this study, we describe the design, engineering and characterisation of a fluorescent peptide biosensor derived from 6‐phosphofructokinase that reports on CDK6 kinase activity through sensitive changes in fluorescence intensity. This biosensor can report on CDK6 activity in a dose‐dependent fashion, thereby enabling quantification of differences in kinase activity in complex and physiologically relevant environments. Further implementation of this biosensor in different lung and melanoma cell lines, as well as in mesothelioma cell lines derived from patients together with a CDK4 biosensor highlighted differences in kinase activity between CDK6 and CDK4 kinase. This work demonstrates the utility of these selective tools for monitoring two closely related kinases comparatively and simultaneously in the same samples, thereby offering attractive perspectives for diagnostic and therapeutic purposes.
Dengue fever complicated by hemophagocytic lymphohistiocytosis: Report of 2 cases and bone marrow findings
Authors: Chang Chee Yik , Rajappan Mahaletchumi , Zaid Masliza , Ong Edmund L. C. 
Published: October 2020

AbstractHemophagocytic lymphohistiocytosis is a rare but severe complication of dengue infection which carries a high mortality. This report highlights the importance of early recognition of this condition as prompt appropriate treatment improves outcomes.
Photoactive Nickel Complexes in Cross‐Coupling Catalysis
Authors: Wenger Oliver S. 
Published: October 2020

AbstractTransition metal catalyzed cross‐coupling reactions are important in chemical synthesis for the formation of C−C and C‐heteroatom bonds. Suitable catalysts are frequently based on palladium or nickel, and lately the cheaper and more abundant first‐row transition metal element has been much in focus. The combination of nickel catalysis with photoredox chemistry has opened new synthetic possibilities, and in some cases electronically excited states of nickel complexes play a key role. This is a remarkable finding, because photo‐excited metal complexes are underexplored in the context of organic bond‐forming reactions, and because the photophysics and the photochemistry of first‐row transition metal complexes are underdeveloped in comparison with their precious metal‐based congeners. Consequently, there is much potential for innovation at the interface of synthetic‐organic and physical‐inorganic chemistry. This Minireview highlights recent key findings in light‐driven nickel catalysis and identifies essential concepts for the exploitation of photoactive nickel complexes in organic synthesis.
Direct Catalytic Asymmetric Addition of α‐Fluoronitriles to Aldehydes
Authors: Balaji Pandur Venkatesan , Li Zhao , Saito Akira , Kumagai Naoya , Shibasaki Masakatsu 
Published: October 2020

AbstractA fluorine‐containing tetrasubstituted stereogenic center is a highly valued structural feature in medicinal chemistry. Herein, we describe the direct coupling of racemic α‐fluoronitriles and aldehydes promoted by a chiral CuI/Barton's base catalytic system, delivering α‐tetrasubstituted α‐fluoro‐β‐hydroxynitriles with satisfactory stereoselection. The stereochemical course was positively biased by the combined use of asymmetrical achiral thiourea as a supplementary ligand for CuI, which significantly enhanced the stereoselectivity. Both aromatic and aliphatic aldehydes were implemented to provide densely and stereoselectively functionalized chiral building blocks with aliphatic and aromatic tails.
European heart health survey 2019
Authors: Gaede Luise , Sitges Marta , Neil Johnson , Selvi Eleonara , Woan William , Derks Richard , Möllmann Helge 
Published: October 2020

AbstractBackgroundRising life expectancy in the western population is increasing the prevalence of heart valve diseases (HVD).HypothesisThe level of awareness and initial screening for HVD should be sufficient. The potential impact of HVD on the daily activities of the elderly population in Europe might affect our society.Methods and ResultsA survey was conducted, including a total of 12 832 people aged ≥ 60 years in 11 European countries. Of all the people surveyed, 5.6% could correctly describe aortic valve stenosis. Most participants (75.0%) claimed they regularly do activities like sports or social activities, 29.2% provide care for a family member, friend or acquaintance. The majority (69.2%) would be prevented from doing these activities by symptoms such as chest pain, fatigue or shortness of breath. Having chest pain (76.5%) and shortness of breath (57.8%) were reasons for most people to arrange an appointment with their GP, whereas only 26.2% would visit a GP for fatigue. 67.6% of respondents claimed to be checked with a stethoscope by their GP occasionally, never, or only when they ask. The preferred treatment option for HVD is a keyhole procedure (45.8%), whereas open heart surgery would only be preferred by 7.0%.ConclusionKnowledge about HVD is still low. Neither appointments with a GP driven by symptoms nor regular use of a stethoscope are a reliable guarantee for early diagnosis. With the over 60s in Europe playing an active role in social life, awareness campaigns and regular heart health checks may guarantee early diagnosis and treatment of HVD.