bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Reusable CNT‐Supported Single‐Atom Iron Catalyst for the Highly Efficient Synthesis of C−N Bonds
Authors: Ding Qifeng , Yu Yang , Huang Fei , Zhang Lihui , Zheng Jian‐Guo , Xu Mingjie , Baell Jonathan B. , Huang He 
Published: February 2020

AbstractC−N bond formation is regarded as a very useful and fundamental reaction for the synthesis of nitrogen‐containing molecules in both organic and pharmaceutical chemistry. Noble‐metal and homogeneous catalysts have frequently been used for C−N bond formation, however, these catalysts have a number of disadvantages, such as high cost, toxicity, and low atom economy. In this work, a low‐toxic and cheap iron complex (iron ethylene‐1,2‐diamine) has been loaded onto carbon nanotubes (CNTs) to prepare a heterogeneous single‐atom catalyst (SAC) named Fe‐Nx/CNTs. We employed this SAC in the synthesis of C−N bonds for the first time. It was found that Fe‐Nx/CNTs is an efficient catalyst for the synthesis of C−N bonds starting from aromatic amines and ketones. Its catalytic performance was excellent, giving yields of up to 96 %, six‐fold higher than the yields obtained with noble‐metal catalysts, such as AuCl3/CNTs and RhCl3/CNTs. The catalyst showed efficacy in the reactions of thirteen aromatic amine substrates, without the need for additives, and seventeen enaminones were obtained. High‐angle annular dark‐field scanning transmission electron microscopy in combination with X‐ray absorption spectroscopy revealed that the iron species were well dispersed in the Fe‐Nx/CNTs catalyst as single atoms and that Fe‐Nx might be the catalytic active species. This Fe‐Nx/CNTs catalyst has potential industrial applications as it could be cycled seven times without any significant loss of activity.
Magnesocenophane‐Catalyzed Amine Borane Dehydrocoupling
Authors: Wirtz Lisa , Haider Wasim , Huch Volker , Zimmer Michael , Schäfer André 
Published: February 2020

AbstractThe Lewis acidities of a series of [n]magnesocenophanes (1 a–d) have been investigated computationally and found to be a function of the tilt of the cyclopentadienyl moieties. Their catalytic abilities in amine borane dehydrogenation/dehydrocoupling reactions have been probed, and C[1]magnesocenophane (1 a) has been shown to effectively catalyze the dehydrogenation/dehydrocoupling of dimethylamine borane (2 a) and diisopropylamine borane (2 b) under ambient conditions. Furthermore, the mechanism of the reaction with 2 a has been investigated experimentally and computationally, and the results imply a ligand‐assisted mechanism involving stepwise proton and hydride transfer, with dimethylaminoborane as the key intermediate.
A Phosphinine‐Derived 1‐Phospha‐7‐Bora‐Norbornadiene: Frustrated Lewis Pair Type Activation of Triple Bonds
Authors: Leitl Julia , Jupp Andrew R. , Habraken Evi R. M. , Streitferdt Verena , Coburger Peter , Scott Daniel J. , Gschwind Ruth M. , Müller Christian , Slootweg J. Chris , Wolf Robert 
Published: February 2020

AbstractSalt metathesis of 1‐methyl‐2,4,6‐triphenylphosphacyclohexadienyl lithium and chlorobis(pentafluorophenyl)borane affords a 1‐phospha‐7‐bora‐norbornadiene derivative 2. The C≡N triple bonds of nitriles insert into the P−B bond of 2 with concomitant C−B bond cleavage, whereas the C≡C bonds of phenylacetylenes react with 2 to form λ4‐phosphabarrelenes. Even though 2 must formally be regarded as a classical Lewis adduct, the C≡N and C≡C activation processes observed (and the mild conditions under which they occur) are reminiscent of the reactivity of frustrated Lewis pairs. Indeed, NMR and computational studies give insight into the mechanism of the reactions and reveal the labile nature of the phosphorus–boron bond in 2, which is also suggested by detailed NMR spectroscopic studies on this compound. Nitrile insertion is thus preceded by ring opening of the bicycle of 2 through P−B bond splitting with a low energy barrier. By contrast, the reaction with alkynes involves formation of a reactive zwitterionic methylphosphininium borate intermediate, which readily undergoes alkyne 1,4‐addition.
Risk stratification biomarkers for Staphylococcus aureus bacteraemia
Authors: Cao Yi , Guimaraes Alessander O , Peck Melicent C , Mayba Oleg , Ruffin Felicia , Hong Kyu , Carrasco‐Triguero Montserrat , Fowler Vance G , Maskarinec Stacey A , Rosenberger Carrie M 
Published: February 2020

AbstractObjectivesTo identify risk stratification biomarkers to enrich for the subset of Staphylococcus aureus bacteraemia patients who develop deep‐seated tissue infections with high morbidity and mortality to guide clinical trial enrolment and clinical management.MethodsWe evaluated the prognostic value of eight biomarkers for persistent bacteraemia, mortality and endovascular infection foci in a validation cohort of 160 patients with S. aureus bacteraemia enrolled consecutively over 3 years.ResultsHigh levels of IL‐17A, IL‐10 or soluble E‐selectin at bacteraemia diagnosis correlated with the duration of positive blood cultures. When thresholds defined in an independent cohort were applied, these biomarkers were robust predictors of persistent bacteraemia or endovascular infection. High serum levels of IL‐17A and IL‐10 often preceded the radiographic diagnosis of infective endocarditis, suggesting potential utility for prioritising diagnostic radiographic imaging. High IL‐8 was prognostic for all‐cause mortality, while IL‐17A and IL‐10 were superior to clinical metrics in discriminating between attributable mortality and non‐attributable mortality. High IL‐17A and IL‐10 identified more patients who developed microbiological failure or mortality than were identified by infective endocarditis diagnosis.ConclusionThese biomarkers offer potential utility to identify patients at risk of persistent bacteraemia to guide diagnostic imaging and clinical management. Low biomarker levels could be used to rule out the need for more invasive TEE imaging in patients at lower risk of infective endocarditis. These biomarkers could enable clinical trials by enriching for patients with the greatest need for novel therapies.
Trait means predict performance under water limitation better than plasticity for seedlings of Poaceae species on the eastern Tibetan Plateau
Authors: Li Honglin , Li Xilai , Zhou Xiaolong 
Published: February 2020

AbstractWater availability may be altered by changes in precipitation under global climate change in alpine areas. Trait means and plasticity are important for plants in response to a changing environment. In an examination of alpine plant responses to changed water availability, and for determination of how trait means and plasticity predict the performance (e.g., biomass) of these species, seeds of ten Poaceae species from the eastern Tibetan Plateau were sown and grown in a manipulated environment during a growing season in which rainfall was removed and other climate conditions remained unchanged. Growth and leaf traits of these species were measured. We found significant effects of moderate water stress on the seedling biomass of these species; however, the responses of these species to changed water condition were strongly dependent on species identity. For example, the biomass of some species significantly decreased under moderate drought, whereas that of others were either significantly increased or unaffected. This pattern was also observed for growth and leaf traits. Overall, the alpine Poaceae species showed low plasticity of traits in response to water availability relative to reports from other areas. Notably, the results show that trait means were better correlated with the productivity than with the plasticity of traits; thus, we argue that the trait means were better predictors of performance than plasticity for alpine Poaceae species. Poaceae species in alpine areas are important for forage production and for water catchment health worldwide, and these species may face water shortage because of current and future climate change. Understanding the response of alpine Poaceae species to water availability would facilitate our ability to predict the impacts of climate change on the alpine vegetation.
Equitable transform applied to phenology and temperature in a changing climate: Scaling to maintain individuality
Authors: Elphinstone Cassandra , Henry Greg H. R. 
Published: February 2020

AbstractWe describe an equitable transform that can be used to estimate missing data points, determine systematic patterns in data, observe baseline changes, and detect different amplitudes in replicated sequences. It is applicable to short discrete two‐ or three‐dimensional data sets such as biological life cycles or water content in similar media. The technique is independent of the continuity or ordering of sequences but is distinct from methods such as principal component analysis. It is ideally used to preprocess noisy or incomplete data sets prior to analysis with other well‐established techniques. This transformation maintains systematic differences between individual sequences when the underlying pattern is a separable function in two variables added to another function in one of these variables. The equitable transform partitions the original noisy data into the underlying signal determined from the data and its residuals. Points from one sequence can be transformed to any other sequence without losing any information. Information about one or more sequences can be used to infer others with missing data. A link to a github R package is provided so the transform can easily be run on any two‐dimensional data set. Simulated two‐dimensional data sets are used to demonstrate its utility in recovering missing data and scaling/offsetting in one of the dimensions. We used the transform to determine that winter temperatures at a High Arctic site have warmed by 1.8° ± 0.4°C/decade and summer temperatures by 1.1° ± 0.2°C/decade from 1986 to 2007. Applied to 18 yr of phenology data for the tundra plant Dryas integrifolia at the same site, we determined that the annual cycles of phenology events could be modeled accurately. Phenology, in some circumstances, can be described as offsetting and scaling the rate at which life cycle events occur. We introduce the idea of scaling and shifting the seasonal cycle of a reference plant via the equitable transform in order to approximate the behavior of multiple phenological cycles. Relative phenology rates of Dryas integrifolia were found to have increased over time indicating duration of phenological stages have become shorter in recent years, likely in response to the warming climate.
Assessment of Glucose Oxidase Based Enzymatic Fuel Cells Integrated With Newly Developed Chitosan Membranes by Electrochemical Impedance Spectroscopy
Authors: Bahar Tahsin , Yazici M. Suha 
Published: February 2020

AbstractConsiderably stable enzymatic fuel‐cells (single cell and 5‐cells stack) were prepared by using chitosan based membranes along with glucose oxidase attached bioanode. Continuous operation of fuel‐cells were monitored under short circuit conditions reaching half‐life over a week. Detailed analysis for the effects of pH, temperature, buffer types and concentration on different type of in‐house produced chitosan membranes were performed by electrochemical impedance spectroscopy (EIS). EIS was utilized to observe, total electrolyte resistance, charge transfer properties, mass transfer and double layer effects on integrated fuel cells (single cell and 5‐cells stack). Performance of the fuel cells was also analyzed by the polarization experiments. Current density of the fuel cell increased at higher operation temperatures not only due to better enzyme kinetics, but also due to increase in electrolyte (membrane+buffer solution) conductivity. Buffer concentration in the fuel (glucose) solution was found as an important parameter. Under optimum fuel cell operation conditions (i. e. 30–40 °C, pH 5 0.3 M buffer solution), maximum current densities of 3.0–3.2 mA cm−2 were reached. Low‐power devices (i. e. a calculator, step motor) were powered with 5‐cell stack producing 3 mW at 1.3 V.
Profiling of essential oil chemical composition of some Lamiaceae species extracted using conventional and microwave‐assisted hydrodistillation extraction methods via chemometrics tools
Authors: Hassanein Heba D. , El‐Gendy Abd El‐Nasser G. , Saleh Ibrahim A. , Hendawy Saber F. , Elmissiry Moustafa M. , Omer Elsayed A. 
Published: February 2020

AbstractThis study investigated the potential use of microwave energy as an effective technique for the extraction of essential oil (EO) from some plant species belonging to Lamiaceae family growing in Egypt, involving Origanum majorana L., Mentha pipereta L., Mentha longifolia L., Origanum syriacum L., Lavandula angustifolia L., Rosmarinus officinalis L., and Thymus vulgaris L., in comparison with conventional extraction using hydrodistillation (HD) approach, in terms of extraction time, oil yields, and chemical composition. The results showed that the use of microwave in a relevant technique, namely microwave‐assisted hydrodistillation (MAHD) required an extraction of 60 minutes, while HD required 180 minutes. In general, EO yield being extracted by MAHD was higher than those extracted by HD. Gas chromatography in combination with mass spectrometry (GC/MS) analysis indicated noticeable quantitative changes in EOs composition extracted by MAHD and HD extraction methods. Except for O majorana L., GC/MS analysis of extracted oils using MAHD showed higher amounts of oxygenated constituents compared to HD extraction. The results of this study introduced MAHD as rapid, economical and environmental friendly extraction method. A comparative analysis was stated here between the EOs of all plant species under study on chemometric tools such as principal components analysis (PCA) and agglomerative hierarchical clustering (AHC). In general, the PCA results showed that there is significant variation between species in the quality and quantity of EO composition. However, no significant difference is observed based on the extraction method used (HD and MAHD).
The effectiveness of living well multicultural‐lifestyle management program among ethnic populations in Queensland, Australia
Authors: Gallegos Danielle , Do Hong , To Quyen Gia , Vo Brenda , Goris Janny , Alraman Hana 
Published: February 2020

AbstractIssueSome migrant groups have higher risks of deaths and chronic diseases due to barriers associated with socioeconomic disadvantage, social isolation, racism, language, poor access to health services and low levels of health literacy. However, few culturally tailored interventions have targeted ethnic groups in Australia. This study evaluated the effectiveness of the Living Well Multicultural‐Lifestyle Management Program (LWM‐LMP) in Queensland, Australia.MethodsThe LWM‐LMP was originally co‐designed with the targeted communities. Participants aged ≥18 years were eligible to participate without a fee. The evaluation was a quasi‐experimental design without a control group, with data collected at baseline, the end of the programme and after‐programme follow‐up at week 14. The programme lasted 8 weeks with one group‐based session of 120 minutes delivered each week in local community venues. Each session also included time to undertake physical activity (PA). Eating and PA behaviours were self‐reported. Weight, height, waist circumference and blood pressure were measured using standard protocols.ResultsParticipants were more likely to consume ≥2 servings of fruit/day, five servings of vegetable/day, low‐fat milk, processed meat, fast food, hot chips/fries, salty snacks, sweet snacks, sweet beverages less than once per week and meet the PA recommendation of ≥150 minutes/wk (P < .001) at week 8. Weight, BMI, waist circumference, waist‐to‐height ratio and blood pressure were also improved at week 8. Many of the changes were sustained at week 14.ConclusionsThe LWM‐LMP was effective in improving participants’ lifestyle behaviours and cardiometabolic indicators.So whatEngaging targeted communities in designing interventions focussed on healthy personal behaviours helps with delivery and implementation. Behavioural interventions should be culturally tailored to increase their effectiveness.
The determination of the optimal strip‐thickness of anti‐scatter grids for a given grid ratio and strip height
Authors: Zhou Abel , Yin Yuming , Tan Qi , L. White Graeme , Davidson Rob 
Published: February 2020

AbstractIn X‐ray imaging, anti‐scatter grids are used to reduce scatter radiation reaching image receptors, hence improving image quality. Optimization of grid performance is essential for improving image diagnostic quality and minimizing radiation doses to patients. This work investigated the performance of a series of grid designs modeled from the design of typically focused grid with grid ratio 8:1 (r8) and strip height 1.7 mm (h1.7) for high‐energy radiographic applications. Monte Carlo simulation was used to evaluate designs (r8h1.7) which had the strip thickness changed from 6 to 150 μm in 2 μm increments and the interspace distance fixed at 214 μm. The transmissions of radiation in grid materials were modeled by using a regression with radial‐basis‐function‐networks (RBFNS). KSNR was then determined from RBFNS models of radiation transmissions. The optimal strip‐thickness was obtained at the maximum signal‐to‐noise ratio (SNR) improvement factor (KSNR). For high‐energy applications at 100 peak‐kilo‐voltage (kVp) and 30 cm PMMA thickness, the optimal lead‐strip‐thickness was found approximately 74 μm resulting in a strip‐frequency approximately 35 per cm (N35). Using the optimal thickness for imaging condition at 100 kVp and 30 cm thickness, the KSNR would increase by approximately 5.3%. This work showed the existence of optimal strip‐thickness for a series of grids with a given grid‐ratio, strip‐height, strip‐, and interspace materials. The findings are useful and provide guidance to improve grid designs for better performance that will essentially lead to better image quality and better radiation protection for patients.
Fracture Healing in Collagen-Related Preclinical Models of Osteogenesis Imperfecta
Authors: Zieba Jennifer , Munivez Elda , Castellon Alexis , Jiang Ming-Ming , Dawson Brian , Ambrose Catherine G , Lee Brendan 
Published: February 2020

ABSTRACT
Osteogenesis imperfecta (OI) is a genetic bone dysplasia characterized by bone deformities and fractures caused by low bone mass and impaired bone quality. OI is a genetically heterogeneous disorder that most commonly arises from dominant mutations in genes encoding type I collagen (COL1A1 and COL1A2). In addition, OI is recessively inherited with the majority of cases resulting from mutations in prolyl-3-hydroxylation complex members, which includes cartilage-associated protein (CRTAP). OI patients are at an increased risk of fracture throughout their lifetimes. However, non-union or delayed healing has been reported in 24% of fractures and 52% of osteotomies. Additionally, refractures typically go unreported, making the frequency of refractures in OI patients unknown. Thus, there is an unmet need to better understand the mechanisms by which OI affects fracture healing. Using an open tibial fracture model, our study demonstrates delayed healing in both Col1a2 G610c/+ and Crtap −/− OI mouse models (dominant and recessive OI, respectively) that is associated with reduced callus size and predicted strength. Callus cartilage distribution and chondrocyte maturation were altered in OI, suggesting accelerated cartilage differentiation. Importantly, we determined that healed fractured tibia in female OI mice are biomechanically weaker when compared with the contralateral unfractured bone, suggesting that abnormal OI fracture healing OI may prime future refracture at the same location. We have previously shown upregulated TGF-β signaling in OI and we confirm this in the context of fracture healing. Interestingly, treatment of Crtap −/− mice with the anti-TGF-β antibody 1D11 resulted in further reduced callus size and predicted strength, highlighting the importance of investigating dose response in treatment strategies. These data provide valuable insight into the effect of the extracellular matrix (ECM) on fracture healing, a poorly understood mechanism, and support the need for prevention of primary fractures to decrease incidence of refracture and deformity in OI patients. © 2020 American Society for Bone and Mineral Research.
Identification of downregulated circRNAs from tissue and plasma of patients with gastric cancer and construction of a circRNA‐miRNA‐mRNA network
Authors: Liu Jingfu , Li Zhen , Teng Wenhao , Ye Xianren 
Published: February 2020

AbstractThe connection between circular RNAs (circRNAs) and gastric cancer has been reported widely in recent years. However, previous studies have focused mainly on circRNAs from gastric cancer tissue. The objectives of the present study were to detect dysregulated circRNAs from both tissue and plasma of patients with gastric cancer and to explore their potential roles in the pathogenesis of gastric cancer. Expression profiles of circRNAs were obtained from the Gene Expression Omnibus (GEO) and analyzed using the GEO2R tool to identify differential expressed circRNAs. The significance threshold was set as |log2 (fold change)| > 2 and adjusted P < .05. The microRNA (miRNA) binding sites of the differentially expressed circRNAs were predicted using the Circular RNA Interactome web tool. TargetScan and the miRNet database were used to predict the miRNA target genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed using Database for Annotation Visualization and Integrated Discovery. Hub genes were identified and a network was constructed with Cytoscape. The overall survival rates for the selected miRNAs and messenger RNAs were evaluated by Kaplan‐Meier Plotter. A total of three downregulated circRNAs (hsa_circ_0001190, hsa_circ_0036287, and hsa_circ_0048607) were identified in this study. Six miRNAs and eight hub genes met the significance criteria and were selected for further analysis. A circRNA‐miRNA‐hub gene network was constructed based on three circRNAs, six miRNAs, and eight hub genes. Evaluation of overall survival rates for the hub genes showed that low expression levels of GADD45A, PPP1CB, PJA2, and KLF2 were associated with poor overall survival. This study identified potential novel plasma circRNA biomarkers and provides insights into the underlying mechanisms of gastric cancer pathogenesis.