bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous flow hydrogenation with Pd complexes of pyridine‐benzotriazole ligands
Authors: Yılmaz Filiz , Hür Deniz 
Published: July 2021

AbstractThe use of continuous flow systems in chemical synthesis provides great advantages in terms of sustainability, efficiency, and safety. The ability to control reaction parameters such as temperature, pressure, and catalyst exposure in flow system enables rapid optimization of reaction conditions. In the present study, palladium complexes of 1‐(piridin‐2‐il)‐1H‐benzo[d][1,2,3]triazol, N‐((1H‐benzo[d][1,2,3]triazol‐1‐il)metil)piridin‐2‐amin, and (1H‐benzo[d][1,2,3]triazol‐1‐yl)(pyridin‐2‐yl)methanone ligands were synthesized and characterized. The catalytic activities of complexes are investigated in the hydrogenation of various alkenes such as styrene, cyclohexene, and 1‐octene under continuous flow conditions. The complexes showed very high activity at 10‐bar H2 pressure and 50°C for short periods of 5–10 min. The catalysts reused for 10 cycles with no significant loss of catalytic activity.
Analysis of mechanical, thermal, electrical andEMIshielding properties of graphite/carbon fiber reinforced polypropylene composites prepared via a twin screw extruder
Authors: Kaushal Ashish , Singh Vishal 
Published: July 2021

AbstractThe present research focuses on the preparation of an efficient material that acts as a deterrent to electromagnetic pollution. In this study, graphite and carbon fiber (CF) reinforced polypropylene (PP) composites (GCF) are prepared using a melt processing technique via a twin‐screw extruder. The prepared composites were evaluated for mechanical, thermal, DC conductivity, and EMI shielding properties. There is a rise in the tensile strength (4.32%) and thermal stability (6.57%) of composites were recorded as compared to pure PP. The fractured morphology of the composites showed the breakdown of CF, leading to the improvement in the tensile strength of the composites. An increase in electrical conductivity was seen at maximum (GCF4) filler loading indicating 2.31 × 10−4 S/cm which is much better than the pure PP value (2.07 × 10−10 S/cm). The maximum value of shielding effectiveness is achieved at the maximum weight percentage of filler loading which is −44.43 dB with a thickness of 2 mm covering the X‐band (8.2–12.4 GHz).
Electrospun scaffolds for wound healing applications from poly(4‐hydroxybutyrate): A biobased and biodegradable linear polymer with high elastomeric properties
Authors: Keridou Ina , Franco Lourdes , Martínez Juan C. , Turon Pau , Del Valle Luis J. , Puiggalí Jordi 
Published: July 2021

AbstractElectrospun scaffolds of the biodegradable and biocompatible poly‐4‐hydroxybutyrate (P4HB) polyester have been prepared using horizontal and vertical set‐up configurations of electrospinning. Specifically, it has been evaluated the influence of solvent, polymer concentration, and processing parameters, such as applied voltage, flow rate, and needle tip‐collector distance. Scaffolds obtained under the most favorable conditions were characterized in terms of crystallinity, lamellar supramolecular order, thermal (including calorimetric and thermogravimetric data), mechanical, and surface properties. Results pointed out significant differences with respect to commercial sutures (based in P4HB, e.g., MonoMax®) and demonstrated that electrospun scaffolds were constituted by crystalline microfibers with a tangled distribution that leads to high modulus Young modulus (4 MPa), maximum strength (28 MPa), and elongation (360%). Furthermore, new scaffolds had thermal stability and a rough surface that led to a hydrophobic character (105°). Scaffolds could also be successfully loaded during the electrospinning process with a peptide analog to the fibroblast growth factor (e.g., CYRSRKYSSWYVALKRC), giving rise to fully biocompatible samples with a clear acceleration in wound healing.
Anti‐Cortactin Autoantibodies Are Associated With Key Clinical Features in Adult Myositis But Are Rarely Present in Juvenile Myositis
Authors: Pinal‐Fernandez Iago , Pak Katherine , Gil‐Vila Albert , Baucells Andres , Plotz Benjamin , Casal‐Dominguez Maria , Derfoul Assia , Martinez‐Carretero Maria Angeles , Selva‐O'Callaghan Albert , Sabbagh Sara , Casciola‐Rosen Livia , Albayda Jemima , Paik Julie , Tiniakou Eleni , Danoff Sonye K. , Lloyd Thomas E. , Miller Frederick W. , Rider Lisa G. , Christopher‐Stine Lisa , Mammen Andrew L. ,   the Childhood Myositis Heterogeneity Collaborative Study Group
Published: July 2021

ObjectiveTo define the prevalence and clinical phenotype of anti‐cortactin autoantibodies in adult and juvenile myositis.MethodsIn this longitudinal cohort study, anti‐cortactin autoantibody titers were assessed by enzyme‐linked immunosorbent assay in 670 adult myositis patients and 343 juvenile myositis patients as well as in 202 adult healthy controls and 90 juvenile healthy controls. The prevalence of anti‐cortactin autoantibodies was compared among groups. Clinical features of patients with and those without anti‐cortactin autoantibodies were also compared.ResultsAnti‐cortactin autoantibodies were more common in adult dermatomyositis (DM) patients (15%; P = 0.005), particularly those with coexisting anti–Mi‐2 autoantibodies (24%; P = 0.03) or anti–NXP‐2 autoantibodies (23%; P = 0.04). In adult myositis, anti‐cortactin was associated with DM skin involvement (62% of patients with anti‐cortactin versus 38% of patients without anti‐cortactin; P = 0.03), dysphagia (36% versus 17%; P = 0.02) and coexisting anti–Ro 52 autoantibodies (47% versus 26%; P = 0.001) or anti‐NT5c1a autoantibodies (59% versus 33%; P = 0.001). Moreover, the titers of anti‐cortactin antibodies were higher in patients with interstitial lung disease (0.15 versus 0.12 arbitrary units; P = 0.03). The prevalence of anti‐cortactin autoantibodies was not different in juvenile myositis patients (2%) or in any juvenile myositis subgroup compared to juvenile healthy controls (4%). Nonetheless, juvenile myositis patients with these autoantibodies had a higher prevalence of “mechanic's hands” (25% versus 7%; P = 0.03), a higher number of hospitalizations (2.9 versus 1.3; P = 0.04), and lower peak creatine kinase values (368 versus 818 IU/liter; P = 0.02) than those without anti‐cortactin.ConclusionThe prevalence of anti‐cortactin autoantibodies is increased in adult DM patients with coexisting anti–Mi‐2 or anti–NXP‐2 autoantibodies. In adults, anti‐cortactin autoantibodies are associated with dysphagia and interstitial lung disease.
Anatomy education for medical students in the United Kingdom and Republic of Ireland in 2019: A 20‐year follow‐up
Authors: Smith Claire F. , Freeman Samuel K. , Heylings David , Finn Gabrielle M. , Davies D. Ceri 
Published: July 2021

AbstractAnatomical education in the United Kingdom (UK) and Ireland has long been under scrutiny, especially since the reforms triggered in 1993 by the General Medical Council's “Tomorrow's Doctors.” The aim of the current study was to investigate the state of medical student anatomy education in the UK and Ireland in 2019. In all, 39 medical schools completed the survey (100% response rate) and trained 10,093 medical students per year cohort. The teachers comprised 760 individuals, of these 143 were employed on full‐time teaching contracts and 103 were employed on education and research contracts. Since a previous survey in 1999, the number of part‐time staff has increased by 300%, including a significant increase in the number of anatomy demonstrators. In 2019, anatomy was predominantly taught to medical students in either a system‐based or hybrid curriculum. In all, 34 medical schools (87%) used human cadavers to teach anatomy, with a total of 1,363 donors being used per annum. Gross anatomy teaching was integrated with medical imaging in 95% of medical schools, embryology in 81%, living anatomy in 78%, neuroanatomy in 73%, and histology in 68.3%. Throughout their five years of study, medical students are allocated on average 85 h of taught time for gross anatomy, 24 h for neuroanatomy, 24 h for histology, 11 h for living anatomy, and 10 for embryology. In the past 20 years, there has been an average loss of 39 h dedicated to gross anatomy teaching and a reduction in time dedicated to all other anatomy sub‐disciplines.
Copper‐Catalyzed Synthesis of 5‐Aryl‐6‐(Trifluoromethyl)‐2,3‐Dihydropyrazolo[1,2‐a]Pyrazol‐1(5H)‐One
Authors: Zhang Xinyu , Wang Hui , Xie Lili , You Chenhui , Han Xiaoyan , Weng Zhiqiang 
Published: July 2021

AbstractAn efficient protocol for the synthesis of 5‐aryl‐6‐(trifluoromethyl)‐2,3‐dihydropyrazolo[1,2‐a]pyrazol‐1(5H)‐one derivatives through a copper‐catalyzed [3+2]‐cycloaddition of azomethine imines with 3,3,3‐trifluoropropyne (generated in situ from dehydrobromination of 2‐bromo‐3,3,3‐trifluoropropene under base conditions) is developed. The advantages of this transformation are the broad substrate scope and the good functional group compatibility. The subsequent oxidation and nucleophilic substitution/aromatization provide a new approach to 4‐trifluoromethylated pyrazol‐1‐yl propanoic acids.
Heterobimetallic Cluster‐Based Coordination Polymers: Assembly, Structures and Third‐Order Nonlinear Optical Properties
Authors: Cao Chen , Bao Shu‐Jin , Tang Xiao‐Yan , Xu Ze‐Ming , Ni Chun‐Yan , Lang Jian‐Ping 
Published: July 2021

AbstractReactions of (NH4)2WS4 with CuCN, CuCN/1,2‐bis(4‐pyridyl)propane (bppa) or [Cu(MeCN)4]PF6/bppa under different reaction conditions afforded a set of two‐ or three‐dimensional W/Cu/S cluster‐based coordination polymers including {[Et4N]2[WS4Cu4(μ‐CN)2(μ‐I)2]}n (1), [WS4Cu4(μ‐CN)2(bppa)2]n (2) and {[WS4Cu4(bppa)4](PF6)2}n (3), respectively. Compound 2 can be readily formed from reaction of 1 with bppa under solvothermal conditions. Compounds 1 and 2 feature two‐dimensional networks with a “sql” topology, while 3 possesses a two‐fold interpenetrated three‐dimensional net with a rare “reo” topology. Compounds 1–3 in DMF exhibited different third‐order nonlinear optical responses, and they all showed a reverse saturable absorption while 2 held a strong self‐focusing effect.
Reduced brain volume and white matter alterations in Shank3‐deficient rats
Authors: Golden Carla E. M. , Wang Victoria X. , Harony‐Nicolas Hala , Hof Patrick R. , Buxbaum Joseph D. 
Published: July 2021

AbstractMutations and deletions in the SHANK3 gene cause the major neurodevelopmental features of Phelan–McDermid syndrome (PMS), which is characterized by intellectual disability, autism spectrum disorder, and sensory hyporeactivity. SHANK3 encodes a key structural component of excitatory synapses important for synaptogenesis. Clinical assessments and limited brain imaging studies of patients with PMS have uncovered regional volume reductions and white matter thinning. While these impairments have been replicated ex vivo in pups of a rat model, brain structure has not been assessed in rats in vivo or in adults. We assessed the brain structure of heterozygous and homozygous adult Shank3‐deficient male rats in comparison to wild‐type littermates with magnetic resonance imaging using both anatomical assessments and diffusion tensor imaging (DTI). Shank3‐deficient rats showed a reduction in overall brain size and the absolute volume of the neocortex, piriform cortex, thalamus, forebrain, inferior and superior colliculi, internal capsule, and anterior commissure. The superior colliculus was decreased in relative volume. DTI revealed that axial diffusion and fractional anisotropy were reduced in the external capsule and mean diffusion was increased in the fornix, suggesting that restriction of diffusion perpendicular to the axis of the axonal fibers was impaired in these white matter tracts. Therefore, Shank3‐deficient rats replicate the reduced brain volume and altered white matter phenotypes present in PMS. Our results indicate that the loss of a glutamatergic synaptic protein, Shank3, has structural consequences at the level of the whole brain. The brain regions that were altered represent potential cross‐species structural biomarkers that warrant further study.
Tazarotene‐induced gene 1 interacts with Polo‐like kinase 2 and inhibits cell proliferation in HCT116 colorectal cancer cells
Authors: Wang Chun‐Hua , Lu Tzung‐Ju , Wang Lu‐Kai , Wu Chang‐Chieh , Chen Mao‐Liang , Kuo Chan‐Yen , Shyu Rong‐Yaun , Tsai Fu‐Ming 
Published: July 2021

AbstractTazarotene‐induced gene 1 (TIG1) is considered to be a tumor suppressor gene that is highly expressed in normal or well‐differentiated colon tissues, while downregulation of TIG1 expression occurs in poorly differentiated colorectal cancer (CRC) tissues. However, it is still unclear how TIG1 regulates the tumorigenesis of CRC. Polo‐like kinases (Plks) are believed to play an important role in regulating the cell cycle. The performance of PLK2 in CRC is negatively correlated with the differentiation status of CRC tissues. Here, we found that PLK2 can induce the growth of CRC cells and that TIG1 can prevent PLK2 from promoting the proliferation of CRC cells. We also found that the expression of PLK2 in CRC cells was associated with low levels of Fbxw7 protein and increased expression of cyclin E1. When TIG1 was coexpressed with PLK2, the changes in Fbxw7/cyclin E1 levels induced by PLK2 were reversed. In contrast, silencing TIG1 promoted the proliferation of CRC, and when PLK2 was also silenced, the proliferation of CRC cells induced by TIG1 silencing was significantly inhibited. The above research results suggest that TIG1 can regulate the tumorigenesis of CRC by regulating the activity of PLK2.
Enhancing the Separation Efficiency in Acetic Acid Manufacturing by Methanol Carbonylation
Authors: Dimian Alexandre C. , Kiss Anton A. 
Published: July 2021

AbstractAcetic acid is an essential chemical used in the production of many chemical products. Using methanol as bio‐building block, the acetic acid produced may be incorporated in bio‐based products. This study deals with enhancing the efficiency of separations in a process using a homogeneous catalyst, which is the most applied today industrially. Several configurations for downstream processing by distillation are investigated using effective combinations of fully thermally coupled columns, namely, dividing‐wall columns, alone or combined with heat pumps. The results indicate that the three‐column direct sequence may be effectively replaced by a two‐column sequence. Overall, the total annual cost is reduced by 34 %. The cost of compressor may be paid back in 1.5 years by the saved energy. Low energy intensity is achieved by tight integration with the reaction section.
Static Retention of Dynamic Chiral Arrangements for Achiral Shear Thinning Metal–Organic Colloids
Authors: Huang Jian‐Cai , Xiao Hui , Chen Zhixin , Zheng Wenxu , Huang Chang‐Cang , Wu Shu‐Ting , Xie Zenghong , Zhuang Naifeng 
Published: July 2021

AbstractChiral compounds are known to be important not only because they are the fundamental components of living organisms, but also for their unique chiroptical properties. In recent years, scientists have fabricated several chiral organic supramolecular aggregates by using chiral physical fields, such as vortex flow. Herein, the relationship between dynamic chiroptical properties and rheological nature is discussed, suggesting the shear thinning properties of non‐Newtonian fluids might help colloidal particles adopt a chiral arrangement in vortices. Furthermore, the storage modulus of colloids could be increased by adding a linking agent, which successfully kept the dynamic chiroptical properties in the static state. Moreover, the salt effect on the host–guest interaction involved in the colloids was studied, the results suggested a significant enhancement of the transferred dynamic circular dichroism for the achiral guest molecule.
Carbon Dioxide Capture Enhanced by Pre‐Adsorption of Water and Methanol in UiO‐66
Authors: Jajko Gabriela , Kozyra Paweł , Gutiérrez‐Sevillano Juan José , Makowski Wacław , Calero Sofia 
Published: July 2021

AbstractThe rapidly rising level of carbon dioxide in the atmosphere resulting from human activity is one of the greatest environmental problems facing our civilization today. Most technologies are not yet sufficiently developed to move existing infrastructure to cleaner alternatives. Therefore, techniques for capturing carbon dioxide from emission sources may play a key role at the moment. The structure of the UiO‐66 material not only meets the requirement of high stability in contact with water vapor but through the water pre‐adsorbed in the pores, the selectivity of carbon dioxide adsorption is increased. We successfully applied the recently developed methodology for water adsorption modelling. It allowed to elucidate the influence of water on CO2 adsorption and study the mechanism of this effect. We showed that water is adsorbed in octahedral cage and stands for promotor for CO2 adsorption in less favorable space than tetrahedral cages. Water plays a role of a mediator of adsorption, what is a general idea of improving affinity of adsorbate. On the basis of pre‐adsorption of methanol as another polar solvent, we have shown that the adsorption sites play a key role here, and not, as previously thought, only the interaction between the solvent and quadrupole carbon dioxide. Overall, we explained the mechanism of increased CO2 adsorption in the presence of water and methanol, as polar solvents, in the UiO‐66 pores for a potential post‐combustion carbon dioxide capture application.
Vibrational circular dichroism of d‐amino acid‐containing peptide NdWFamide in the crystal form
Authors: Yamagishi Hiroki , Sato Hisako , Kawamura Izuru 
Published: July 2021

AbstractMicrocrystals of l‐Asn‐d‐Trp‐l‐Phe‐NH2 (NdWFamide), a tripeptide derived from Aplysia kurodai that exhibits invertebrate cardiac activity, were evaluated by vibrational circular dichroism (VCD). The chirality of the tryptophan residue at the second position in NdWFamide was associated with the conformation and biological characteristics. The VCD spectrum of NdWFamide was a mirror image of its enantiomer; however, it was significantly different from that of its diastereomer, NWFamide, which is its precursor. The obtained VCD signals of NdWFamide were in good agreement with the VCD signals that were calculated based on the optimized aggregates of NdWFamide, which formed a helical‐like backbone conformation. The evaluation of the VCD results revealed the conformation of NdWFamide in the crystalline state and succeeded in distinguishing its stereoisomers. Therefore, this study demonstrates VCD as a useful method for the structural analysis of naturally occurring d‐amino acid‐containing peptides.
Chemomechanical effects of oxidizer‐CO2 systems upon hydraulically fractured unconventional source rock
Authors: Hull Katherine L. , Abousleiman Younane N. 
Published: July 2021

AbstractCarbon dioxide (CO2) as supercritical (scCO2) or foamed (CO2‐Foam) fluid has been tested many times as a fracturing fluid, though it has not yet proven viable. Many challenges have been identified with scCO2 as a fracturing fluid, including poor additive solubility, low viscosity, and limited accessibility. However, CO2 is known to adsorb to organic matter (OM) and displace methane (i.e., enhanced coal bed methane [ECBM] operations), or to mobilize oil as in tertiary enhanced oil recovery. In this study we augment the efficacy of the kerogen control fluid (KCF) for stimulating unconventional rock formations by alternating aqueous oxidizing fracturing fluid with CO2 injection or by combining oxidizers directly with CO2 as a new additive. To this end, KCF‐CO2 tests were designed to treat OM and extend the depth of permeability enhancement. We report the first attempt to combine oxidizer with CO2 in the presence of source shale rocks at elevated temperature and pressure. Scanning electron microscopy imaging of the treated shale sample surfaces demonstrate potential porosity and permeability enhancement, though some mineral and organic deposits are also observed, which may prove to be detrimental. Meanwhile, alternating water‐based KCF with CO2 provides a potential improvement to the KCF as predicted by early lab results on OM. The KCF‐CO2 concept has no equivalent to date in unconventional hydraulic fracturing operations. This technology will contribute to reducing the footprint of anthropogenic CO2 and enhancing its permanent sequestration in unconventional stimulated reservoirs, compliant with our global clean energy initiative of carbon capture, utilization, and storage.
Effects of control temperature, ablation time, and background tissue in radiofrequency ablation of osteoid osteoma: A computer modeling study
Authors: Rivas Ricardo , Hijlkema Rudy B. , Cornelissen Ludo J. , Kwee Thomas C. , Jutte Paul C. , van Ooijen Peter M. A. 
Published: July 2021

AbstractTo study the effects of the control temperature, ablation time, and the background tissue surrounding the tumor on the size of the ablation zone on radiofrequency ablation (RFA) of osteoid osteoma (OO). Finite element models of non‐cooled temperature‐controlled RFA of typical OOs were developed to determine the resulting ablation radius at control temperatures of 70, 80, and 90°C. Three different geometries were used, mimicking common cases of OO. The ablation radius was obtained by using the Arrhenius equation to determine cell viability. Ablation radii were larger for higher temperatures and also increased with time. All geometries and control temperatures tested had ablation radii larger than the tumor. The ablation radius developed rapidly in the first few minutes for all geometries and control temperatures tested, developing slowly towards the end of the ablation. Resistive heating and the temperature distribution showed differences depending on background tissue properties, resulting in differences in the ablation radius on each geometry. The ablation radius has a clear dependency not only on the properties of the tumor but also on the background tissue. Lower background tissue's electrical conductivity and blood perfusion rates seem to result in larger ablation zones. The differences observed between the different geometries suggest the need for patient‐specific planning, as the anatomical variations could cause significantly different outcomes where models like the one here presented could help to guarantee safe and successful tumor ablations.
Monolayer 1T and 1T′ MoSO as Promising Electrocatalyst for Hydrogen Evolution based on First Principle Calculations
Authors: Li Fei‐Fei , Niu Zi‐Ping , Zhang Li‐Xin 
Published: July 2021

AbstractMolybdenum disulfide (MoS2) has been regarded as one of the most promising candidates for replacing Pt group noble metals as an efficient electrocatalyst to enhance the hydrogen evolution reaction (HER) in consideration of its relatively high earth abundance. Recent studies show that the catalytic efficiency of MoS2 for HER can be promoted by the presence of 1T‐phase MoS2. It is hard to precisely control the formation of 1T‐MoS2, however, due to its metastability relative to 2H‐MoS2. Elevating the stability of 1T phase allotrope is therefore of great importance and could be realized by replacing divalent S with monovalent elements or groups according to crystal field theory, which has been demonstrated through our first‐principles density functional theory (DFT) calculation results. Differential Gibbs free energy analysis for hydrogen adsorption (ΔGH*) suggest that 1T and 1T′ MoSO (O doped MoS2) might be taken as potential candidate catalysts for HER process with better performance than 1T and 1T′ MoS2. We also propose a probable approach to synthesize 1T and 1T′ MoSO under oxidation circumstance environment of graphene oxide.