bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transition Metal Complexes of 2,6‐Dibenzhydryl Derived Bisphosphine: Synthesis, Structural Studies and Palladium Complex Promoted Suzuki‐Miyaura Reactions
Authors: Pandey Madhusudan K. , Kote Basvaraj S. , Mondal Dipanjan , Kunchur Harish S. , Radhakrishna Latchupatula , Balakrishna Maravanji S. 
Published: July 2022

AbstractTransition metal chemistry of [Ar*N(CH2PPh2)2] (1) derived from the sterically demanding backbone 2,6‐dibenzhydryl‐4‐methylphenyl core is described. The reactions of 1 with 30 % aq. H2O2 and S8 afforded bischalcogenides [Ar*N(CH2P(O)Ph2)2] (2) and [Ar*N(CH2P(S)Ph2)2] (3), respectively. Treatment of 1 with [M(COD)Cl2] (M=Pd, Pt) in 1 : 1 molar ratios produced chelate complexes cis‐[MCl2{Ar*N(CH2PPh2)2}‐κ2‐P,P] (4, M=Pd; 5, M=Pt), whereas similar reaction between 1 and [Pd(η3‐C3H5)Cl]2 afforded dinuclear complex [{Pd(η3‐C3H5)Cl}2{Ar*N(CH2PPh2)2}‐κ1‐P,P] (6). The reaction of 1 with [Ru(η5‐C5H5)Cl(PPh3)2] in 1 : 1 ratio yielded [{Ru(η5‐C5H5)Cl}{Ar*N(CH2PPh2)2}‐κ2‐P,P] (7). Treatment of 1 with [M(C5H11N)2(CO)4] (M=Mo, W) in 1 : 1 molar ratios afforded cis‐[M(CO)4{Ar*N(CH2PPh2)2}‐κ2‐P,P] (8, M=Mo; 9, M=W). The reaction of 1 with copper(I) halides in 1 : 1 molar ratios produced [Cu(μ2‐X)]2 dinuclear complexes [{Cu(μ2‐X)}2{Ar*N(CH2PPh2)2}2‐κ2‐P,P}] [10, X=Cl; 11, X=Br; and 12, X=I]. Most of these compounds show various C−H⋅⋅⋅π interactions. Bischalcogenides 2 and 3 showed intramolecular hydrogen bonding type interactions, C−H⋅⋅⋅O (2.554 Å) and C−H⋅⋅⋅S (2.825 Å) between the methylene hydrogens of –NCH2PPh2 groups with O or S atoms, which was also evinced by QTAIM and NCI analysis. Bisphosphine 1 was found to be very effective in palladium catalyzed Suzuki‐Miyaura couplings of aryl chlorides with aryl boronic acids.
Polymer Supported Methionine Selenoxide as an Excellent Immobilized Oxidant for the Formation of Disulfide Bonds in Peptides
Authors: Wang Yafang , Xing Yueyue , Sun Jingjing , Song Changing , Shen Shigang , Huo Shuying 
Published: July 2022

AbstractTwo PEG‐based polymer supported methionine selenoxide (MeSeO) named TentaGel‐MetSeO and PEG‐MetSeO were synthesized and used as immobilized oxidants for the purpose of formation of disulfide bonds in peptides under aqueous conditions. Peptide disulfide bonds were successfully synthesized by use of the two immobilized oxidants. Moreover, the oxidation of the methionine residue to its sulfoxide derivate was not observed. By comparison, the yield of disulfide‐containing peptide via PEG‐MetSeO oxidation is higher than that of the disulfide‐containing peptide via TentaGel‐MetSeO oxidation. PEG‐MetSeO can be used at least 10 cycles without the significant yield decrease. The two immobilized oxidants can be separated from the reaction mixture using filtration, making the peptide synthesis more easily.
Lewis Base‐catalyzed β‐Addition of (Arylsulfonyl) fluoromethane Derivatives to Allenoates
Authors: Liu Yong‐Liang , Wang Xiao‐Ping , Li Ya 
Published: July 2022

AbstractA highly selective TMG‐catalyzed β‐addition of (arylsulfonyl)fluoromethane derivatives to allenoates has been developed. Cyano, nitro, and ester‐functionalized (arylsulfonyl)fluoromethanes are all suitable substrates, giving a series of structurally diverse β‐addition products bearing a stereogenic fluorinated carbon center. A possible reaction pathway is also presented.
A Polythiophene Material Featuring a Conjugated Carbonyl Side Group as an Anode for Lithium‐Ion Batteries
Authors: Zhang Chengjun , Chen Sha , Zhou Guangying , Hou Qiong , Wang Yuhai , Shi Guang 
Published: July 2022

AbstractConverting small organic molecules to their lithium salts or polymerization effectively solves the capacity fading caused by the dissolution of small organic molecules in electrolytes. While polymer lithium salts have the characteristics of small molecular lithium salts and polymers and can obtain good cycle stability and rate performance. The 3‐carboxylithium substituted thiophene (3‐TCOOLi) and polymer (P3‐TCOOLi) anode materials for lithium‐ion batteries were synthesized, and their electrochemical properties were compared. Compared with the small‐molecule lithium salt 3‐TCOOLi electrode, the polymer P3‐TCOOLi electrode exhibits superior cycling and rate performance. The P3‐TCOOLi electrode still has a specific capacity of 390 mAh g−1 after 100 cycles at a current density of 50 mA g−1. During the rate charge and discharge process, when the current density increased to 1000 mA g−1, the specific capacity was 305 mAh g−1. It shows that the idea of small molecule lithium salt polymerization is feasible.
A Potential PIK3CA Inhibitor to Develop an Anticancer Drug
Authors: Vique‐Sánchez José Luis , Benítez‐Cardoza Claudia Guadalupe 
Published: July 2022

AbstractAccording to the global cancer statistics published by the American Cancer Society (2020), the incidence and mortality of cancer are rapidly increasing worldwide. Therefore, it is necessary to develop new drugs that have greater effectiveness and lower side effects than the current drugs. In this study we used the PIK3CA enzyme as therapeutic target, because there are studies that showed that PIK3CA plays a critical role to develop cancer, strongly related to tumor proliferation, migration, and clinical prognosis by its functions on the PI33K/AKT signaling pathway. The aim of this research is to determine a selective compound to PIK3CA, by molecular docking using a library of nearly 500,000 compounds, to develop a new anticancer drug to decrease the PIK3CA functions in the cancer processes. It was determined the C5 compound with a cytotoxic effect on in vitro cultures of cancer cell lines, due to a probable specific interaction in PIK3CA, Cys420, Glu453, Glu542, Glu545 amino acids, this region is necessary for the catalytic subunit p110α in the PIK3CA enzyme. This research evaluated the potential anticancer effect of C5 compound with acceptable citotoxicity, toxicity theoretical and LD50 results; other analyses will be necessary to continue this development as a new anticancer drug.
The applications of single‐atom alloys in electrocatalysis: Progress and challenges
Authors: Da Yumin , Jiang Rui , Tian Zhangliu , Han Xiaopeng , Chen Wei , Hu Wenbin 
Published: July 2022

AbstractThe development of cost‐effective and highly efficient electrocatalysts to accelerate distinct electrochemical reactions is essential to help the industry to achieve a low‐carbon footprint. Single‐atom alloys (SAAs) with the characteristics of unique electronic structures, well‐defined active sites, and maximum atom utilization demonstrate promising potential to replace traditional noble metal catalysts. SAAs are expected to tailor the adsorption properties of reaction species, thus promoting electrocatalytic behaviors. Herein, representative synthetic strategies including wet chemistry, galvanic replacement, dealloying, and atomic layer deposition are introduced, followed by a summary of applications of SAAs in hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, and ethanol electro‐oxidation to provide an in‐depth understanding of the structure–activity relationship. Moreover, the challenges and perspectives in this emerging field of SAAs are discussed.
“Wearing a Mask Won't Protect Us from Our History”: The Impact of COVID‐19 on Black Children and Families
Authors: Bogan Erin , Adams‐Bass Valerie N. , Francis Lori A. , Gaylord‐Harden Noni K. , Seaton Eleanor K. , Scott Judith C. , Williams Joanna L. 
Published: July 2022

ABSTRACTThe data on COVID‐19 show an irrefutable and disturbing pattern: Black Americans are contracting and dying from COVID‐19 at rates that far exceed other racial and ethnic groups. Due to historical and current iterations of racism, Black Americans have been forced into conditions that elevate their risk for COVID‐19 and consequently place Black children at the epicenter of loss across multiple domains of life. The current paper highlights the impact of the pandemic on Black children at the individual, family, and school levels. Based on an understanding of the influence of structural racism on COVID‐19 disparities, policy recommendations are provided that focus on equitable access to quality education, home ownership, and employment to fully address the needs of Black children and families during and after the pandemic. Research, practice, and policy recommendations are made to journal editors, funding agencies, grant review panels, and researchers regarding how research on COVID‐19 should be framed to inform intervention efforts aimed at improving the situation of Black children and families.
The first belemnite of boreal ancestry from the Early Cretaceous (Valanginian) of the western Tethys: implications for belemnite ecology
Authors: Mutterlose Jörg , Picollier Marie‐Claire , Dzyuba Oksana 
Published: July 2022

AbstractThe first occurrence of the belemnite species Liobelus acrei (formerly Acroteuthis acrei) is reported from the Lower Cretaceous (Valanginian) of the Vocontian Basin (VB; south‐east France). This first record of the genus Liobelus (Family Cylindroteuthididae), which is commonly attributed to the latest Jurassic and Early Cretaceous of the Boreal Realm, revises the spatial distribution pattern of boreal belemnites significantly. The Valanginian belemnite assemblages of the VB are dominated by genera of Tethyan ancestry, including both Duvaliidae (Berriasibelus, Castellanibelus, Duvalia, Pseudobelus) and Belemnopseidae (Adiakritobelus, Hibolithes, Mirabelobelus, Vaunagites). These two groups of Tethyan taxa comprise more than 99.9% of the belemnite‐rich assemblages of the Valanginian of the VB. The occurrence of a boreal specimen documents an isolated immigration of belemnites from the north in the early Valanginian. At the same time most Tethyan belemnite taxa are absent from the Boreal Realm, only Duvalia, Pseudobelus and Hibolithes have been described from North‐East Greenland, and Hibolithes from Svalbard. Based on these diverging biogeographical patterns of the Tethyan belemnite genera we establish two taxonomically different belemnite faunas: Tethyan Fauna 1 (Duvalia, Pseudobelus, Hibolithes), which has a near global, Tethyan‐wide and even boreal distribution, and Tethyan Fauna 2 (Adiakritobelus, Berriasibelus, Castellanibelus, Mirabelobelus, Vaunagites), which is less widely distributed and is restricted to southern Europe. These different spatial distribution patterns shed light on the ecology, migration patterns and evolution of Early Cretaceous belemnites.
Model‐based systems engineering for a small‐lift launch facility
Authors: Taraila Walter McGee , Asundi Sharanabasaweshwara 
Published: July 2022

AbstractA study of model‐based systems engineering (MBSE) applied to a small‐lift launch facility is presented. The research uses Systems Modeling Language (SysML) products and functional diagrams to document the ground systems on a launch pad servicing a small class payload (0–2 tons). With the projected growth in launch cadence of small‐lift rockets in the coming decade, there is a need to design increasingly complex launch systems with greater efficiency. The potential improvements in project communication, quality, and productivity are explored by developing a model following the ISO/IEC 15288 technical process framework and the International Council on Systems Engineering (INCOSE) Object‐Oriented Systems Engineering Method (OOSEM) methodology. The stakeholder requirements are defined and analyzed to provide traceability to individual systems and subsystems. An architecture is proposed by generating engineering artifacts such as piping and instrumentation drawings. The concepts are verified and validated by performing engineering trade studies concentrated on the pneumatic and fuel subsystems.
Selective Phosphorylation of RNA‐ and DNA‐Nucleosides under Prebiotically Plausible Conditions
Authors: Bechtel Maximilian , Hümmer Eva , Trapp Oliver 
Published: July 2022

AbstractNucleotides play a fundamental role in organisms, from adenosine triphosphate (ATP), the body‘s main source of energy, to cofactors of enzymatic reactions (e. g. coenzyme A), to nucleoside monophosphates as essential building blocks of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Although nucleotides play such an elemental role, there is no pathway to date for the selective formation of nucleoside 5′‐monophosphates. Here, we demonstrate a selective reaction pathway for 5’ mono‐phosphorylation for all canonical purine and pyrimidine bases under exceptionally mild prebiotic relevant conditions in water and without using a condensing agent. The pivotal reaction step involves activated imidazolidine‐4‐thione phosphates. The selective formation of non‐cyclic mono‐phosphorylated nucleosides represents a novel and unique route to nucleotides and opens exciting perspectives in the study of the origins of life.
On the safe use of prior densities for Bayesian model selection
Authors: Llorente Fernando , Martino Luca , Curbelo Ernesto , López‐Santiago Javier , Delgado David 
Published: July 2022

AbstractThe application of Bayesian inference for the purpose of model selection is very popular nowadays. In this framework, models are compared through their marginal likelihoods, or their quotients, called Bayes factors. However, marginal likelihoods depend on the prior choice. For model selection, even diffuse priors can be actually very informative, unlike for the parameter estimation problem. Furthermore, when the prior is improper, the marginal likelihood of the corresponding model is undetermined. In this work, we discuss the issue of prior sensitivity of the marginal likelihood and its role in model selection. We also comment on the use of uninformative priors, which are very common choices in practice. Several practical suggestions are discussed and many possible solutions, proposed in the literature, to design objective priors for model selection are described. Some of them also allow the use of improper priors. The connection between the marginal likelihood approach and the well‐known information criteria is also presented. We describe the main issues and possible solutions by illustrative numerical examples, providing also some related code. One of them involving a real‐world application on exoplanet detection.This article is categorized under:Statistical Models > Bayesian ModelsStatistical Models > Fitting ModelsStatistical Models > Model Selection
Direct regulation of TCR rearrangement and expression by E proteins during early T cell development
Authors: Anderson Michele K. , da Rocha Juliana Dutra Barbosa 
Published: July 2022

Abstractγδ T cells are widely distributed throughout mucosal and epithelial cell‐rich tissues and are an important early source of IL‐17 in response to several pathogens. Like αβ T cells, γδ T cells undergo a stepwise process of development in the thymus that requires recombination of genome‐encoded segments to assemble mature T cell receptor (TCR) genes. This process is tightly controlled on multiple levels to enable TCR segment assembly while preventing the genomic instability inherent in the double‐stranded DNA breaks that occur during this process. Each TCR locus has unique aspects in its structure and requirements, with different types of regulation before and after the αβ/γδ T cell fate choice. It has been known that Runx and Myb are critical transcriptional regulators of TCRγ and TCRδ expression, but the roles of E proteins in TCRγ and TCRδ regulation have been less well explored. Multiple lines of evidence show that E proteins are involved in TCR expression at many different levels, including the regulation of Rag recombinase gene expression and protein stability, induction of germline V segment expression, chromatin remodeling, and restriction of the fetal and adult γδTCR repertoires. Importantly, E proteins interact directly with the cis‐regulatory elements of the TCRγ and TCRδ loci, controlling the predisposition of a cell to become an αβ T cell or a γδ T cell, even before the lineage‐dictating TCR signaling events.This article is categorized under:
Immune System Diseases > Stem Cells and Development
Immune System Diseases > Genetics/Genomics/Epigenetics
Potential of atmospheric pressure ionization sources for the analysis of free fatty acids in clinical and biological samples by gas chromatography-mass spectrometry
Authors: Görs Paul E. , Wittenhofer Pia , Ayala-Cabrera Juan F. , Meckelmann Sven W. 
Published: July 2022

AbstractBecause of the central role of fatty acids in biological systems, their accurate quantification is still important. However, the impact of the complex matrix of biologically and clinically relevant samples such as plasma, serum, or cells makes the analysis still challenging, especially, when free non-esterified fatty acids have to be quantified. Here we developed and characterized a novel GC–MS method using pentafluorobenzyl bromide as a derivatization agent and compared different ionization techniques such as atmospheric pressure chemical ionization (APCI), atmospheric pressure chemical photoionization (APPI), and negative ion chemical ionization (NICI). The GC-APCI-MS showed the lowest limits of detection from 30 to 300 nM for a broad range of fatty acids and a similar response for various fatty acids from a chain length of 10 to 20 carbon atoms. This allows the number of internal standards necessary for accurate quantification to be reduced. Moreover, the use of pentafluorobenzyl bromide allows the direct derivatization of free fatty acids making them accessible for GC–MS analysis without labor-intense sample pretreatment.
Arens regularity for totally ordered semigroups
Authors: Dales H. G. , Strauss D. 
Published: July 2022

AbstractLetSbe a semigroup. We shall consider the centres of the semigroup$$(\beta \,S, \,\Box \,)$$(βS,□)and of the algebra$$(M(\beta \,S), \,\Box \,)$$(M(βS),□), where$$M(\beta \,S)$$M(βS)is the bidual of the semigroup algebra$$(\ell ^{\,1}(S),\,\star \,)$$(ℓ1(S),⋆), and whether the semigroup and the semigroup algebra are Arens regular, strongly Arens irregular, or neither. We shall also determine subsets of$$S^*$$S∗and of$$M(S^*)$$M(S∗)that are ‘determining for the left topological centre’ (DLTC sets) of$$\beta \,S$$βSand$$M(\beta \,S)$$M(βS). It is known that, when the semigroupSis cancellative,$$\ell ^{\,1}(S)$$ℓ1(S)is strongly Arens irregular and that there is a DLTC set consisting of two points of$$S^*$$S∗. In contrast, there is little that has been published about the Arens regularity of$$\ell ^{\,1}(S)$$ℓ1(S)whenSis not cancellative. Totally ordered, abelian semigroups, with the map$$(s,t)\rightarrow s \wedge t$$(s,t)→s∧tas the semigroup operation, provide examples which show that several possibilities can occur. We shall determine the centres of$$\beta \,S$$βSand of$$M(\beta \,S)$$M(βS)for all such semigroups, and give several examples, showing that the minimum cardinality of DTC sets may be arbitrarily large, and, in particular, we shall give an example of a countable, totally ordered, abelian semigroupSwith this operation for which there is no countable DTC set for$$\beta S$$βSor for$$M(\beta S)$$M(βS). There was no previously-known example of an abelian semigroupSfor which$$\beta \,S$$βSor$$M(\beta S)$$M(βS)did not have a finite DTC set.
Reactive astrogliosis is associated with higher cerebral glucose consumption in the early Alzheimer’s continuum
Authors: Salvadó Gemma , Milà-Alomà Marta , Shekari Mahnaz , Ashton Nicholas J. , Operto Grégory , Falcon Carles , Cacciaglia Raffaele , Minguillon Carolina , Fauria Karine , Niñerola-Baizán Aida , Perissinotti Andrés , Benedet Andréa L. , Kollmorgen Gwendlyn , Suridjan Ivonne , Wild Norbert , Molinuevo José Luis , Zetterberg Henrik , Blennow Kaj , Suárez-Calvet Marc , Gispert Juan Domingo ,   on behalf of the ALFA Study
Published: July 2022

Abstract
Purpose
Glial activation is one of the earliest mechanisms to be altered in Alzheimer’s disease (AD). Glial fibrillary acidic protein (GFAP) relates to reactive astrogliosis and can be measured in both cerebrospinal fluid (CSF) and blood. Plasma GFAP has been suggested to become altered earlier in AD than its CSF counterpart. Although astrocytes consume approximately half of the glucose-derived energy in the brain, the relationship between reactive astrogliosis and cerebral glucose metabolism is poorly understood. Here, we aimed to investigate the association between fluorodeoxyglucose ([18F]FDG) uptake and reactive astrogliosis, by means of GFAP quantified in both plasma and CSF for the same participants.

Methods
We included 314 cognitively unimpaired participants from the ALFA + cohort, 112 of whom were amyloid-β (Aβ) positive. Associations between GFAP markers and [18F]FDG uptake were studied. We also investigated whether these associations were modified by Aβ and tau status (AT stages).

Results
Plasma GFAP was positively associated with glucose consumption in the whole brain, while CSF GFAP associations with [18F]FDG uptake were only observed in specific smaller areas like temporal pole and superior temporal lobe. These associations persisted when accounting for biomarkers of Aβ pathology but became negative in Aβ-positive and tau-positive participants (A + T +) in similar areas of AD-related hypometabolism.

Conclusions
Higher astrocytic reactivity, probably in response to early AD pathological changes, is related to higher glucose consumption. With the onset of tau pathology, the observed uncoupling between astrocytic biomarkers and glucose consumption might be indicative of a failure to sustain the higher energetic demands required by reactive astrocytes.
Severity of Illness Impacts Outcomes More than Admitting Service for Isolated Hip Fracture Patients
Authors: Bauman Zachary M. , Phillips Paige , Cantrell Emily , Raposo‐Hadley Ashley , Patel Megha , Evans Charity H. , Kamien Andrew 
Published: July 2022

AbstractIntroductionIsolated hip fractures (IHF) are common injuries in the elderly. Controversy exists about which hospital service is best suited to manage these patients. We hypothesize that baseline patient severity of illness (SOI) score drives patient outcomes, not the hospital service managing these patients.MethodsRetrospective review of all IHF patients from 2014 to 2018 at our Level 1 trauma center. Basic demographics were obtained. Patients were divided into service line they were admitted; surgical vs non‐surgical. Primary outcomes included hospital length of stay (HLOS), time to OR, time to VTE prophylaxis, complication rate (defined by the Trauma Quality Improvement Program), 30‐day mortality, and readmissions. SOI score (which is DRG‐based) was controlled to see if any differences in primary outcomes occurred between cohorts. Chi‐square was used for categorical variables and regression analysis for continuous variables. Significance was p < 0.05.ResultsA total of 366 total patients were analyzed with the same ISS. A total of 102 were admitted to a surgical service and 264 to a non‐surgical service. Average overall age was 80 year, 66.9% were female, and 86% were Caucasian. There was no statistical difference between outcomes when comparing admitting services. Controlling for SOI score, there was no difference between admitting service for outcomes as well. SOI score was a significant predictor for increased HLOS and complication occurrence (p < 0.001) via regression analysis, with a 6.06‐fold increase in complication rate from mild to moderate SOI score (p = 0.001).ConclusionThere is no difference in outcomes based on admitting service and process measures. However, the SOI score is perhaps a better predictor of outcomes for isolated hip fracture patients.