bluuebunny/crossref_metadata_2025_split huggingface dataset:
Four modified sodium alginate/carboxymethylcellulose blends for prednisone delivery
Authors: Silva Kláudia Maria Machado Neves , Costa Bruna Lopes , Nunes Dourado Lays Fernanda , Silva Rummenigge Oliveira , Silva‐Cunha Armando , Santos Anderson Kenedy , Resende Rodrigo Ribeiro , Faria Paulo Eustáquio , Campos Rubio Juan Carlos , Goulart Gisele Assis Castro , Silva‐Caldeira Priscila Pereira 
Published: December 2020

AbstractPolysaccharides have been widely used for the development of drug delivery systems. These systems can be physicochemically modified to enhance their stabilities and control their drug release profiles. However, such modifications cannot alter their biocompatibility or toxicity. Herein, four structurally modified sodium alginate/carboxymethylcellulose blends are synthesized and loaded with prednisone, and the effects of the modifications on their hydrolytic degradation rates, biocompatibilities, toxicities, and drug release profiles are investigated. All the blends are ionically cross‐linked with Ca2+ and Fe3+. Blend 1 is not modified further, blend 2 is additionally reinforced with 8% w/w of cellulose nanocrystals, blend 3 is treated with epoxidized linseed oil to develop a hydrophobic layer, and blend 4 is chemically cross‐linked with epichlorohydrin. Blends 2 and 4 exhibit similar physicochemical characteristics, appropriate hydrolytic degradation rates and drug release patterns, as well as biocompatibility and non‐toxicity. In‐vitro studies using the osteoblasts and CAM assay demonstrate that blends 2 and 4 are also biocompatible and non‐toxic. In contrast, blend 1 exhibits the highest drug release rate, followed by blend 3.
Negative CG dinucleotide bias: An explanation based on feedback loops between Arginine codon assignments and theoretical minimal RNA rings
Authors: Demongeot Jacques , Moreira Andrés , Seligmann Hervé 
Published: December 2020

AbstractTheoretical minimal RNA rings are candidate primordial genes evolved for non‐redundant coding of the genetic code's 22 coding signals (one codon per biogenic amino acid, a start and a stop codon) over the shortest possible length: 29520 22‐nucleotide‐long RNA rings solve this min‐max constraint. Numerous RNA ring properties are reminiscent of natural genes. Here we present analyses showing that all RNA rings lack dinucleotide CG (a mutable, chemically instable dinucleotide coding for Arginine), bearing a resemblance to known CG‐depleted genomes. CG in “incomplete” RNA rings (not coding for all coding signals, with only 3–12 nucleotides) gradually decreases towards CG absence in complete, 22‐nucleotide‐long RNA rings. Presumably, feedback loops during RNA ring growth during evolution (when amino acid assignment fixed the genetic code) assigned Arg to codons lacking CG (AGR) to avoid CG. Hence, as a chemical property of base pairs, CG mutability restructured the genetic code, thereby establishing itself as genetically encoded biological information.
Cell‐Free Synthesis of Selenoproteins in High Yield and Purity for Selective Protein Tagging
Authors: Welegedara Adarshi P. , Maleckis Ansis , Bandara Ruchira , Mahawaththa Mithun C. , Dilhani Herath Iresha , Jiun Tan Yi , Giannoulis Angeliki , Goldfarb Daniella , Otting Gottfried , Huber Thomas 
Published: December 2020

AbstractThe selenol group of selenocysteine is much more nucleophilic than the thiol group of cysteine. Selenocysteine residues in proteins thus offer reactive points for rapid post‐translational modification. Herein, we show that selenoproteins can be expressed in high yield and purity by cell‐free protein synthesis by global substitution of cysteine by selenocysteine. Complete alkylation of solvent‐exposed selenocysteine residues was achieved in 10 minutes with 4‐chloromethylene dipicolinic acid (4Cl‐MDPA) under conditions that left cysteine residues unchanged even after overnight incubation. GdIII−GdIII distances measured by double electron–electron resonance (DEER) experiments of maltose binding protein (MBP) containing two selenocysteine residues tagged with 4Cl‐MDPA‐GdIII were indistinguishable from GdIII−GdIII distances measured of MBP containing cysteine reacted with 4Br‐MDPA tags.
N‐(3′,4′‐dimethoxycinnamonyl) anthranilic acid alleviates severe acute pancreatitis by inhibiting intestinal barrier dysfunction and NF‐κB activation
Authors: Zhao Zhicheng , Lu Li , Li Weidong 
Published: December 2020

AbstractSevere acute pancreatitis (SAP) can affect intestinal barrier with a high mortality. To date, effective therapies for SAP are still in urgently need. The purpose of this study was to investigate the role of anthranilic acid active synthetic derivative, N‐(3′,4′‐dimethoxycinnamonyl) anthranilic acid (3,4‐DAA), in intestinal barrier dysfunction of SAP. In this study, SAP mice model was induced by caerulein combined with lipopolysaccharide (LPS). SAP mice were pretreated with 3,4‐DAA orally. Histological structures of pancreatic and intestinal tissues were observed via hematoxylin–eosin (H&E) staining. Pancreas myeloperoxidase (MPO), serum lipase, and amylase were detected using corresponding kits. Western blot analysis and reverse transcription and quantitative PCR (RT‐qPCR) were employed to determine the levels of inflammatory factors in both pancreatic and intestinal tissues. Moreover, the levels of intestinal barrier‐related proteins, NLRP3 inflammasome and NF‐κB pathway were examined by western blot analysis. Result revealed that 3,4‐DAA significantly attenuated pancreas and intestine damage, inhibited the release of inflammatory factors and intestinal barrier dysfunction. Moreover, the expression of NLRP3 and phospho‐NF‐κB p65 in pancreatic and intestinal tissues was notably suppressed by 3,4‐DAA. To sum up, these results demonstrated that 3,4‐DAA could ameliorate SAP, partly attributing to the inhibition of intestinal barrier dysfunction and the release of inflammatory factors. These findings may provide a new mechanism support for 3,4‐DAA application in the clinical treatment of SAP.
Political economy of renewable resource federalism
Authors: Sanchirico James N. , Blackwood Julie C. , Fitzpatrick Ben , Kling David M. , Lenhart Suzanne , Neubert Michael G. , Shea Katriona , Sims Charles B. , Springborn Michael R. 
Published: December 2020

AbstractThe authority to manage natural capital often follows political boundaries rather than ecological. This mismatch can lead to unsustainable outcomes, as spillovers from one management area to the next may create adverse incentives for local decision making, even within a single country. At the same time, one‐size‐fits‐all approaches of federal (centralized) authority can fail to respond to state (decentralized) heterogeneity and can result in inefficient economic or detrimental ecological outcomes. Here we utilize a spatially explicit coupled natural–human system model of a fishery to illuminate trade‐offs posed by the choice between federal vs. state control of renewable resources. We solve for the dynamics of fishing effort and fish stocks that result from different approaches to federal management that vary in terms of flexibility. Adapting numerical methods from engineering, we also solve for the open‐loop Nash equilibrium characterizing state management outcomes, where each state anticipates and responds to the choices of the others. We consider traditional federalism questions (state vs. federal management) as well as more contemporary questions about the economic and ecological impacts of shifting regulatory authority from one level to another. The key mechanisms behind the trade‐offs include whether differences in local conditions are driven by biological or economic mechanisms; degree of flexibility embedded in the federal management; the spatial and temporal distribution of economic returns across states; and the status‐quo management type. While simple rules‐of‐thumb are elusive, our analysis reveals the complex political economy dimensions of renewable resource federalism.
Heart failure after myocardial infarction: incidence and predictors
Authors: Jenča Dominik , Melenovský Vojtěch , Stehlik Josef , Staněk Vladimír , Kettner Jiří , Kautzner Josef , Adámková Věra , Wohlfahrt Peter 
Published: December 2020

AbstractAimsThe aim of the present paper was to provide an up‐to‐date view on epidemiology and risk factors of heart failure (HF) development after myocardial infarction.Methods and resultsBased on literature review, several clinical risk factors and biochemical, genetic, and imaging biomarkers were identified to predict the risk of HF development after myocardial infarction.ConclusionsHeart failure is still a frequent complication of myocardial infarction. Timely identification of subjects at risk for HF development using a multimodality approach, and early initiation of guideline‐directed HF therapy in these patients, can decrease the HF burden.
Transition Metal Complexes Supported by N‐Heterocyclic Carbene‐Based Pincer Platforms: Synthesis, Reactivity and Applications
Authors: Wang Yidan , Zhang Bo , Guo Shuai 
Published: December 2020

AbstractThe combination of NHC (NHC=N‐heterocyclic carbene) and pincer framework has received extensive attention. The relevant transition metal complexes have found manifold applications in various areas spanning from catalysis to optical material chemistry. This minireview focuses on the advances in the synthesis, reactivity study and applications of metal pincer NHCs.
N‐Heterocyclic Silylene Main Group Element Chemistry: Adduct Formation, Insertion into E−X Bonds and Cyclization of Organoazides
Authors: Krahfuss Mirjam J. , Radius Udo 
Published: December 2020

AbstractInvestigations concerning the reactivity of the N‐heterocyclic silylene Dipp2NHSi (1, 1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐en‐2‐ylidene) towards selected alanes and boranes, elemental halides X2 (X=Br, I), selected halide containing substrates such as tin chlorides and halocarbons, as well as organoazides are presented. The NHSi adducts Dipp2NHSi⋅AlI3 (2), Dipp2NHSi⋅Al(C6F5)3 (3), and Dipp2NHSi⋅B(C6F5)3 (4) were formed by the reaction of Dipp2NHSi with the corresponding Lewis acids AlI3, Al(C6F5)3 and B(C6F5)3. Adducts 3 and 4 were tested with respect to their ability to activate small organic molecules, but no frustrated Lewis pair reactivity was observed. Reactions of Dipp2NHSi with Br2, I2, Ph2SnCl2 and Me3SnCl led to formation of Dipp2NHSiBr2 (5), Dipp2NHSiI2 (6), Dipp2NHSiCl2 (7) and {(Me3Sn)N(Dipp)CH}2 (8), respectively. The reaction with the halocarbons methyl iodide, benzyl chloride, and benzyl bromide afforded the insertion products Dipp2NHSi(I)(CH3) (9), Dipp2NHSi(Cl)(CH2Ph) (10) and Dipp2NHSi(Br)(CH2Ph) (11). Reaction of Dipp2NHSi with the organoazides Ad‐N3 (Ad=adamantyl) and TMS‐N3 (TMS=trimethylsilyl) led to the formation of 1‐Dipp2NHSi‐2,5‐bis(adamantyl)‐tetrazoline (12) and bis(trimethylsilyl)amido azido silane (13), respectively. For 2,6‐(diphenyl)phenyl‐N3 C−H activation occurs and a cyclosilamine 14 was isolated.
Mechanistic Insights into the Formation of δ‐Lactones by Cerium‐Catalyzed Aerobic Coupling of β‐Oxoesters with Enol Acetates
Authors: Speldrich Jean‐Marico , Christoffers Jens 
Published: December 2020

Abstractδ‐Valerolactone derivatives are formed by the cerium‐catalyzed, aerobic coupling of β‐oxoesters with enol acetates and dioxygen. The products possess a 1,4‐diketone moiety, thus, the conversion can be regarded as an Umpolung since the β‐oxoesters are oxidized to electrophilic α‐radicals. The transformation has similarities to the Baeyer‐Villiger oxidation (BVO) where the higher substituted residue migrates. An endoperoxidic oxycarbenium ion comparable to the Criegee intermediate in the BVO is proposed as a reaction intermediate in this case of the oxidative C−C coupling reaction, but in contrast to the BVO, the less substituted alkyl residue migrates. It was demonstrated by the conversion of β‐oxoesters with two stereocenters that this 1,2‐alkyl shift proceeds with retention of configuration. A radical chain mechanism of the coupling reaction was furthermore evidenced by the conversion of enol acetates and β‐oxoesters with cyclopropyl substituents. Isolation and characterization of products with opened cyclopropane rings established the constitution of radical intermediates.
A Nanocomposite Containing Carbon Nano‐onions and Polyaniline Nanotubes as a Novel Electrode Material for Electrochemical Sensing of Daidzein
Authors: Olejnik Piotr , Gniadek Marianna , Echegoyen Luis , Plonska‐Brzezinska Marta E. 
Published: December 2020

AbstractGlassy carbon electrode (GCE) were modified with nanocomposites containing conductive polyaniline nanotubes (PANInt) and carbon nano‐onions (CNOs). Herein we report a simple and sensitive way for daidzein (DA) determination at concentrations between 1 and 10 μM by linear sweep voltammetry using GCE/PANInt/CNOs system. The DA electrochemical behavior was examined in two buffer environments (pH 7.5 and 4.5) using electrodes modified with the oxidized CNOs or their derivatives containing carboxyl and benzylamino functional groups. The direct electrooxidation of DA was observed at +0.65 V and +0.8 V at pH 7.5 and at +0.7 V and +1.1 V vs. Ag/AgCl at pH 4.5.
A survey of the European Reference Network EpiCARE on clinical practice for selected rare epilepsies
Authors: Baumgartner Tobias , Carreño Mar , Rocamora Rodrigo , Bisulli Francesca , Boni Antonella , Brázdil Milan , Horak Ondrej , Craiu Dana , Pereira Cristina , Guerrini Renzo , San Antonio‐Arce Victoria , Schulze‐Bonhage Andreas , Zuberi Sameer M. , Hallböök Tove , Kalviainen Reetta , Lagae Lieven , Nguyen Sylvie , Quintas Sofia , Franco Ana , Cross J. Helen , Walker Matthew , Arzimanoglou Alexis , Rheims Sylvain , Granata Tiziana , Canafoglia Laura , Johannessen Landmark Cecilie , Sen Arjune , Rattihalli Rohini , Nabbout Rima , Tartara Elena , Santos Manuela , Rangel Rui , Krsek Pavel , Marusic Petr , Specchio Nicola , Braun Kees P. J. , Smeyers Patricia , Villanueva Vicente , Kotulska Katarzyna , Surges Rainer 
Published: December 2020

AbstractObjectiveClinical care of rare and complex epilepsies is challenging, because evidence‐based treatment guidelines are scarce, the experience of many physicians is limited, and interdisciplinary treatment of comorbidities is required. The pathomechanisms of rare epilepsies are, however, increasingly understood, which potentially fosters novel targeted therapies. The objectives of our survey were to obtain an overview of the clinical practice in European tertiary epilepsy centers treating patients with 5 arbitrarily selected rare epilepsies and to get an estimate of potentially available patients for future studies.MethodsMembers of the European Reference Network for rare and complex epilepsies (EpiCARE) were invited to participate in a web‐based survey on clinical practice of patients with Dravet syndrome, tuberous sclerosis complex (TSC), autoimmune encephalitis, and progressive myoclonic epilepsies including Unverricht Lundborg and Unverricht‐like diseases. A consensus‐based questionnaire was generated for each disease.ResultsTwenty‐six of 30 invited epilepsy centers participated. Cohorts were present in most responding centers for TSC (87%), Dravet syndrome (85%), and autoimmune encephalitis (71%). Patients with TSC and Dravet syndrome represented the largest cohorts in these centers. The antiseizure drug treatments were rather consistent across the centers especially with regard to Dravet syndrome, infantile spasms in TSC, and Unverricht Lundborg / Unverricht‐like disease. Available, widely used targeted therapies included everolimus in TSC and immunosuppressive therapies in autoimmune encephalitis. Screening for comorbidities was routinely done, but specific treatment protocols were lacking in most centers.SignificanceThe survey summarizes the current clinical practice for selected rare epilepsies in tertiary European epilepsy centers and demonstrates consistency as well as heterogeneity in the treatment, underscoring the need for controlled trials and recommendations. The survey also provides estimates for potential participants of clinical trials recruited via EpiCARE, emphasizing the great potential of Reference Networks for future studies to evaluate new targeted therapies and to identify novel biomarkers.
Relating millimeter‐scale turbulence to meter‐scale subtidal erosion and accretion across the fringe of a coastal mangrove forest
Authors: Norris Benjamin K. , Mullarney Julia C. , Bryan Karin R. , Henderson Stephen M. 
Published: December 2020

AbstractWithin a wave‐exposed mangrove forest, novel field observations are presented, comparing millimeter‐scale turbulent water velocity fluctuations with contemporaneous subtidal bed elevation changes. High‐resolution velocity and bed level measurements were collected from the unvegetated mudflat, at the mangrove forest fringe, and within the forest interior over multiple tidal cycles (flood–ebb) during a 2‐week period. Measurements demonstrated that the spatial variability in vegetation density is a control on sediment transport at sub‐meter scales. Scour around single and dense clusters of pneumatophores was predicted by a standard hydraulic engineering equation for wave‐induced scour around regular cylinders, when the cylinder diameter in the equations was replaced with the representative diameter of the dense pneumatophore clusters. Waves were dissipated as they propagated into the forest, but dissipation at infragravity periods (> 30 s) was observed to be less than dissipation at shorter periods (< 30 s), consistent with the predictions of a simple model. Cross‐wavelet analysis revealed that infragravity‐frequency fluctuations in the bed level were occasionally coherent with velocity, possibly indicating scour upstream of dense pneumatophore patches when infragravity waves reinforced tidal currents. Consequently, infragravity waves were a likely driver of sediment transport within the mangrove forest. Near‐bed turbulent kinetic energy, estimated from the turbulent dissipation rate, was also correlated with bed level changes. Specifically, within the mangrove forest and over the unvegetated mudflat, high‐energy events were associated with erosion or near‐zero bed level change, whereas low‐energy events were associated with accretion. In contrast, no single relationship between bed level changes and mean current velocity was applicable across both vegetated and unvegetated regions. These observations support the theory that sediment mobilization scales with turbulent energy, rather than mean velocity, a distinction that becomes important when vegetation controls the development of turbulence.
Morphodynamic effects of vegetation life stage on experimental meandering channels
Authors: Kyuka Tomoko , Yamaguchi Satomi , Inoue Yusuke , Arnez Ferrel Kattia Rubi , Kon Hideto , Shimizu Yasuyuki 
Published: December 2020

AbstractPrevious studies have demonstrated that riparian vegetation leads to channel transformation from a multi‐bar to a single‐thread channel planform. However, it still remains unclear how the presence of pioneer and mature vegetation affects the morphodynamics of single‐thread meandering rivers. In this study, we therefore investigated the effects of vegetation strength on the morphodynamic evolution of an experimental meandering channel. Three physical laboratory experiments were conducted using alfalfa sprouts in different life stages – no vegetation, immature vegetation, and mature vegetation – to simulate different floodplain vegetation strengths. Our results demonstrate that vegetation plays a key role in mediating bank erosion and point‐bar accretion, and that this is reflected in both the evolution of the channel bed as well as the sediment flux. The presence of mature vegetation maintained a deep, single‐thread channel by reducing bank erosion, thereby limiting both channel widening and sediment storage capacity. Conversely, an unvegetated floodplain led to channel widening and high sediment storage capacity. Channel evolution in the unvegetated scenario showed that the active sediment supply from outer bank erosion led to slightly delayed point‐bar accretion on the inner banks due to helical flow, deflecting the surface flow toward the outer banks and causing further erosion. In contrast, in the immature vegetation scenario, the outer banks were also initially eroded, but point‐bar accretion did not clearly progress. This led to a greater width‐to‐depth ratio, resulting in a transition from a single‐ to a multi‐thread channel with minor flow paths on the floodplain. The experimental results suggest that the eco‐morphodynamic effects of young (low‐strength) and mature (high‐strength) vegetation are different. Notably, low‐strength, early‐stage vegetation increases channel complexity by accelerating both channel widening and branching, and therefore might promote the coexistence of multi‐bars and pioneer vegetation.
Recession probabilities for the Eurozone at the zero lower bound: Challenges to the term spread and rise of alternatives
Authors: Fendel Ralf , Mai Nicola , Mohr Oliver 
Published: December 2020

AbstractThis paper examines the recession probability in the Eurozone within the next 12 months at the zero lower bound (ZLB) and explores two new perspectives: a revised measure of the traditional term spread and a modification to detect unstable dynamics driven by animal spirits. We find that the yield curve largely lost its forecasting ability at the ZLB. To remove the downward rigidity of short‐term rates, we suggest a modified version of the term spread which uses a “shadow policy rate,” rather than the 3‐month rate, as the front leg of the spread. We further show that a bivariate specification including both the current state of an indicator as well as its lagged deviation from its trend augments the predictive capability for most indicators significantly.
The behaviour of U.S. stocks to financial and health risks
Authors: Salisu Afees A. , Raheem Ibrahim D. , Eigbiremolen Godstime O. 
Published: December 2020

AbstractThis article examines the hedging effectiveness of U.S. stocks against uncertainties due to equity market (financial risk) and pandemics (health risk), including Covid‐19 pandemic. Consequently, we consider two categories of U.S. stocks—defensive and non‐defensive stocks drawn from 10 different sectors and distinctly analysed over two data samples—pre‐ and post‐Covid periods. We construct a predictive panel data model that simultaneously accounts for both heterogeneity and common correlated effects and also complementarily determine the predictive power of accounting for uncertainties in the valuation of U.S. stocks. We find that hedging effectiveness is driven by the types of stocks and measures of uncertainty. Defensive stocks provide a good hedge for pandemic‐induced uncertainty, and the hedging effectiveness is higher during calm market conditions as compared to turbulent conditions, while both categories lack hedging capability in the face of equity‐induced uncertainty. Finally, we find that the inclusion of uncertainty in the predictive model of U.S. stock returns improves its forecasts and this conclusion is robust to alternative measures of uncertainty and multiple forecast horizons.