bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enantioselective Fluorocyclizations Mediated by Amino‐Acid‐Derived Phthalazine
Authors: Wang Haitao , Wang Yongheng , Liu Shenghui , Mai Yudong , Zong Xiangxin , Gao Hao , Hu Rongbin , Jiang Xiaojian , Yeung Ying‐Yeung 
Published: October 2019

AbstractNovel amino‐acid‐derived phthalazine reagents have been designed and synthesized for the enantioselective fluorocyclizations of prochiral indoles. The scope of reaction is evidenced by 28 examples of fluorinated furoindole and pyrroloindole heterocycles bearing various functionalities with up to 99% ee. The resulting enantioenriched fluorinated products are found to be potent AChE inhibitors. Advantages of the current new chiral reagents include ease in the synthesis of analogues and readily tunable steric/electronic demands.magnified image
Airplug‐Mediated Isolation and Centralization of Single T Cells in Rectangular Microwells for Biosensing
Authors: Sukumar Pavithra , Deliorman Muhammedin , Brimmo Ayoola T. , Alnemari Roaa , Elsori Deena , Chen Weiqiang , Qasaimeh Mohammad A. 
Published: October 2019

AbstractSorting cells in a single cell per microwell format is of great interest to basic biological studies, biotherapeutics, and biosensing including cell phenotyping. For instance, isolation of individual immune T cells in rectangular microwells has been shown to empower the multiplex cytokine profiling at the single cell level for therapeutic applications. The present study, shows that there is an existing bias in temporal cytokine sensing that originates from random “unpredicted” positions of loaded cells within the rectangular microwells. To eliminate this bias, the isolated cells need to be well‐aligned with each other and relative to the sensing elements. Hence, an approach that utilizes the in situ formation and release of airplugs to localize cells toward the center of the rectangular microwells is reported. The chip includes 2250 microwells (each 500 × 50 × 20 µm3) arranged in nine rows. Results show 20% efficiency in trapping single T cells per microwells, where cells are localized within ± 3% of the center of microwells. The developed platform could provide real‐time dynamic and unbiased multiplex cytokine detection from single T cells for phenotyping and biotherapeutics studies.
Lactate and fibrinogen as good predictors of massive transfusion in postpartum hemorrhage
Authors: Okada Asami , Okada Yohei , Inoue Motoi , Narumiya Hiromichi , Nakamoto Osamu 
Published: October 2019

AimThis study aims to identify the clinical factors that can predict the requirement of massive transfusion among patients with postpartum hemorrhage (PPH).MethodsConsecutive anonymized patients with PPH who were treated at the emergency department of our perinatal medical center were examined. Patients who had received transfusions before admission, those who had cardiac arrest on arrival, and those without history of blood gas analysis were excluded. Our primary outcome was the requirement of massive transfusion defined as packed red blood cells of ≥10 units/24 h. Univariable logistic analysis was carried out to identify the odds ratio and 95% confidence interval (CI) of the explanatory variables for the outcome.ResultsA total of 31 patients (massive transfusion, n = 19) were included in the main analysis. The crude odds ratio for fibrinogen per mg/dL and lactate per mmol/L were calculated as 0.98 (95% CI, 0.97–0.99) and 1.62 (95% CI, 1.08–3.02), respectively. The area under the curves for fibrinogen and lactate were 0.814 and 0.734, respectively, and optimal cut‐off values for fibrinogen and lactate were 211 mg/dL and 4 mmol/L, respectively.ConclusionThese findings suggest that lactate and fibrinogen can be predictors for the requirement of massive transfusion in patients with PPH.
Fabrication of Large Single Crystals for Platinum‐Based Linear Polymers with Controlled‐Release and Photoactuator Performance
Authors: Yu Qi , Li Mingmin , Gao Jia , Xu Peixin , Chen Qizhe , Xing Dong , Yan Jie , Zaworotko Michael J. , Xu Jun , Chen Yao , Cheng Peng , Zhang Zhenjie 
Published: October 2019

AbstractPreparation of large single crystals of linear polymers for X‐ray analysis is very challenging. Herein, we employ a coordination‐driven self‐assembly strategy to secure the appropriate head‐to‐tail alignment of anthracene moieties, and for the first time obtained large‐sized Pt‐based linear polymer crystals through a [4+4] cycloaddition of anthracene in a single‐crystal to single‐crystal fashion. Using X‐ray diffraction to determine the polymer crystal structure, we found that both the polymerisation and depolymerisation steps proceed via a stable intermediate. Taking advantage of the temperature‐dependent slow depolymerization, the Pt‐based linear polymer showed potential as a sustained release anticancer drug platform. Utilizing the reversible contraction effect of unit‐cell volume upon irradiation or heating, the stimuli‐responsive crystals were hybridized with polyvinylidene fluoride to obtain a “smart material” with outstanding photoactuator performance.
Atomic Arrangement in Metal‐Doped NiS2 Boosts the Hydrogen Evolution Reaction in Alkaline Media
Authors: Yin Jie , Jin Jing , Zhang Hong , Lu Min , Peng Yong , Huang Bolong , Xi Pinxian , Yan Chun‐Hua 
Published: October 2019

AbstractWe report a novel modulation strategy by introducing transition metals into NiS2 nanosheets (NSs) to flexibly optimize the electronic configurations and atomic arrangement. The Co‐NiS2 NSs exhibit excellent hydrogen evolution reaction (HER) performance with an overpotential of 80 mV at j=10 mA cm−2 and long‐term stability of 90 h in alkaline media. The turnover frequencies (TOFs) of 0.55 and 4.1 s−1 at an overpotential of 100 and 200 mV also confirm their remarkable performance. DFT calculations reveal that the surface dopants abnormally sensitize surface Ni‐3d bands in the long‐range order towards higher electron‐transfer activity, acting as the electron‐depletion center. Meanwhile, the high lying surface S‐sites possess substantially high selectivity for splitting the adsorbing H2O that guarantee the high HER performance within alkaline conditions. This work opens opportunities for enhancing water splitting by atomic‐arrangement‐assisted electronic modulation via a facile doping strategy.
The Quasi‐Binary Acetonitriletriide Sr3[C2N]2
Authors: Clark William P. , Köhn Andreas , Niewa Rainer 
Published: October 2019

AbstractThe first quasi‐binary acetonitriletriide Sr3[C2N]2 has been synthesised and characterised. The nearly colourless crystals were obtained from the reaction of Sr metal, graphite, and elemental N2, generated by decomposition of Sr(N3)2, in a sealed Ni ampoule with the aid of an alkali metal flux. The structure of this compound was analysed via single‐crystal X‐ray diffraction and the identity of the [C2N]3− anion was confirmed by Raman spectroscopy and further investigated by quantum‐chemical methods. Computed interatomic distances within the [C2N]3− anion strikingly match the obtained experimental data.
Bi‐supported Ziegler–Natta TiCl4/MCM‐41/MgCl2 (ethoxide type) catalyst preparation and comprehensive investigations of produced polyethylene characteristics
Authors: Jafariyeh‐Yazdi Elchin , Tavakoli Akram , Abbasi Farhang , Parnian Mohammad Javad , Heidari Amin 
Published: October 2019

ABSTRACTBi‐supported Ziegler–Natta catalysts (TiCl4/MCM‐41/MgCl2 (ethoxide type)) were synthesized to improve the morphology and the properties of polyethylene. The morphology control is a crucial issue in polymerization process, while tailoring the properties of polymers is needed for specific applications. The catalysts were synthesized in different ratios of two supports with impregnation method. The polymerization process was carried out in atmospheric slurry reactor. The catalysts were characterized with scanning electron microscopy ‐ energy dispersive X‐ray spectroscopy (SEM–EDX), inductively coupled plasma, Fourier transform infrared spectrometry (FTIR), and Brunauer‐Emmett‐Teller (BET) methods. The polymers were analyzed with scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry, FTIR, and tensile‐strength analyses. Ubbelohde viscometer and frequency sweep measurements showed that the synthesized polymers are ultra‐high‐molecular‐weight polyethylene. Mechanical properties of polymers showed higher Young's modulus in samples containing MCM‐41, having higher thermal stability supported by TGA analysis. SEM images of bi‐supported catalyst showed a controlled spherical morphology with uniform size distribution. SEM analysis support that the polymers replicate their morphology from catalyst, improving their morphology comparing to MgCl2‐supported catalyst. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48553.
Larger pore volume tetraphenyladamantane‐based hybrid porous polymers: Facile Friedel–Crafts preparation, CO2 capture, and Rhodamine B removal properties
Authors: Wu Yue , Liu Yu , Dou Ruidi , Tang Wenjie , Sun Bin , Gao Tingting , Yang Zhizhou , Zhou Guowei 
Published: October 2019

ABSTRACTSynthesis of covalently linked porous polymers with high surface area and larger pore volume for two or more task‐specific functionalities is always a big challenge. In this article, the facile Friedel–Crafts reaction is employed to construct the hierarchical hybrid porous polymers (HPPs) from tetraphenyladamantane and octavinylsilsesquioxane. The resulting polymers, HPP‐1 to HPP‐3, possessed the surface areas from 1356 to 1511 m2 g−1, and the pore volumes from 2.05 to 2.67 cm3 g−1. All these polymers feature micropores, mesopores, and macropores in nature. The resultant polymers exhibit high CO2 adsorption capacity up to 2.0 mmol g−1 (8.82 wt %), at 273 K, 1.0 bar, and the maximum Rhodamine B (RB) sorption capacity of 653.6 mg g−1. To illustrate the adsorption process, the effects of factors, contact time, initial concentration, temperature, and pH value on the adsorption capacity of RB were studied. The adsorption equilibrium data displayed a better fitting to the Langmuir isotherm model than the Freundlich model and the adsorption kinetics fitted well with the pseudo‐second‐order kinetic model. The recycle experiments displayed that the capacity recovery was still higher than 95% after four cycles. Theses polymers are promising to be the adsorbents for capturing CO2 and removing RB. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 136, 48572.
Ultraviolet radiation aging impact on physicochemical properties of crosslinked polyethylene cable insulation
Authors: Hedir Abdallah , Moudoud Mustapha , Lamrous Omar , Rondot Sébastien , Jbara Omar , Dony Philippe 
Published: October 2019

ABSTRACTThis article deals within the study of the effect of artificial radiations on physical and chemical properties of the crosslinked polyethylene (XLPE) material, widely used for manufacturing high‐voltage cables. Within this framework, several experimental tests, using essential characterization techniques, were performed to study XLPE behavior under ultraviolet (UV) aging. Attenuated total reflection Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X‐ray diffraction, and scanning electron microscopy were thus carried out to identify the main structure changes of the material before and after exposure to UV. In addition, appearance changes and DC (Direct Current) volume resistivity were evaluated. The obtained results showed that UV radiation has a great effect on the physicochemical properties of XLPE cable insulation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48575.
Addressing models of Maori interaction and regional variation in New Zealand: an analysis of stone adzes from the Auckland (Tamaki) region
Authors: KNEEBONE BRENDAN , MCALISTER ANDREW 
Published: October 2019

ABSTRACTThis study examines evidence for change in adze form and raw materials in the Auckland (Tamaki) region using a sample of 144 adzes from 11 securely dated assemblages spanning the pre‐European Maori sequence. Non‐destructive portable X‐ray fluorescence geochemical analyses indicate that the assemblages were dominated by two stone sources throughout the sequence; locally available Motutapu greywacke, and Tahanga basalt from the Coromandel Peninsula some 100 km distant. Additional analyses, incorporating adze form and use‐life data, indicate that both materials were used in a similar manner. The results of this study suggest that, although patterns of change argued for in existing models of New Zealand's prehistory provide a broad overview of general trends, targeted studies also are required to identify regional variation.
Duff's adze typology versus Polynesian adze exchanges
Authors: RICHARDS MICHELLE J. 
Published: October 2019

ABSTRACTThe inter‐archipelago exchange of adzes after colonisation was not considered in the widely referred to culture historical Polynesian adze typology developed by New Zealand archaeologist, Roger Duff. This portable x‐ray fluorescence (pXRF) geochemical study re‐examined the assemblage of the adzes in museum collections that were classified into Duff Types by archaeologists Gonzalo Figueroa and Eduardo Sanchez. This paper investigates the geochemical patterning of the Polynesian basalt adze types found on the Pitcairn and Gambier Islands by (1) identifying volcanic rock type of the artefact (2) matching the geological sources used to make the artefacts using a Discriminant Function Analysis (DFA) and, (3) comparing an artefact's identified source to its recorded find spot. The results of the analyses conducted in this paper identified that 16 (8%) adzes had originated from different island groups than where they were collected from in the twentieth century. These adze exchanges provide more evidence of long‐distance Polynesian connections that occurred after people initially colonised central east Polynesia and thus further refutes the idea that these islands were occupied in isolation – a critical re‐evaluation of Duff's typology is therefore required.
Development of true orthophotomaps of the fortified settlement at Biskupin, Site 4, based on archival data
Authors: Zawieska Dorota , Markiewicz Jakub , Kopiasz Jarosław 
Published: October 2019

AbstractThis article describes the results of the project to reconstruct a Lusatian culture fortified settlement at Biskupin (one of the most well‐known archaeological sites in Poland) using various archival data. This research work will cover Site 4 at Biskupin, based on the archaeological examinations conducted there during the period 1934–1939, i.e. pre‐war photographs acquired from different heights, e.g. from a captive balloon (maximum height up to 150 m) from a blimp (at a height of 50 to 1000/1100 m) and from an aeroplane (at a height of 200 m, 300 m and up to 3 km). Modern technology enables the creation of true orthophotomaps, which are used to amend the missing drawing documentation created in situ during pre‐war archaeological excavations. The orientation of archival, non‐metric photographs acquired from different flight heights for interpretation purposes (but not for metric documentation purposes) was performed using both structure‐from‐motion algorithms (implemented in the Agisoft PhotoScan software) and the conventional approach based on Gruber points. The investigated area was divided into four sections and all the images were orientated in one reference system, which was defined during the surveys and excavations. The estimated orientation accuracy at the check points was in the range of 0.1 to 0.4 m. The final true orthophotomaps, with reference to the maintained vector drawing, were analysed. The estimated relative error was smaller than 3%. The photogrammetric products will allow for a better understanding of construction as a whole, and for the recognition of particular structures, in particular, by taking into account functional and chronological aspects.
Kilonova afterglow rate from spherical and axisymmetrical models
Authors: Kóbori J. 
Published: October 2019

AbstractDetecting the afterglows of double‐neutron star merger events is a challenging task because of the quick fading of the observed flux. In order to create an efficient observing strategy for their observing method, it is crucial to know their intrinsic rate. Unfortunately, the numerous models existing today predict this rate on a very wide range. Our goal in this paper is to compare the different levels of approximations in order to determine their reliability. We find that there is a significant discrepancy in the expected detection rate between the spherical and axisymmetrical models (∼18 and ≲ 1 yr−1, respectively). In addition, choosing different models for the input parameters (for example, redshift and time delay distribution) has also a strong effect on the results.
Astronomical photographic data archives: Recent status
Authors: Hudec Rene 
Published: October 2019

AbstractI briefly present and discuss the recent status (with emphasis on digitization and data access) of astronomical photographic data archives worldwide, both photometric and spectroscopic, including various digitization techniques, automated data evaluation pipelines, astrophysical use, and public access. Although there are two major astronomical plate digitization projects (Harvard DASCH USA and APPLAUSE representing German Bamberg, Potsdam and Hamburg plate collections), the majority of astronomical photographic data archives are still awaiting digitization. Numerous plate archives have been visited, and in many of them, the glass plates are affected by various degradation types such as gold decease, sometimes progressing so fast that digitization is of great importance, taking into account the enormous scientific value of these databases.
Impact of micro and macroporous TFF membranes on product sieving and chromatography loading for perfusion cell culture
Authors: Pinto Nuno D. S. , Napoli William N. , Brower Mark 
Published: October 2019

AbstractBioprocess intensification can be achieved through high cell density perfusion cell culture with continuous protein capture integration. Protein passage and cell retention are commonly accomplished using tangential flow filtration systems consisting of microporous membranes. Significant challenges, including low efficiency and decaying product sieving over time, are commonly observed in these cell retention devices. Here, we demonstrate that a macroporous membrane overcomes the product sieving challenges when comparing to several other membrane chemistries and pore sizes within the microporous range. This way, variable chromatography column loading is avoided. The macroporous membrane yielded a 13,000 L/m2 volumetric throughput. The membrane's cut‐off size results in an increased permeate turbidity due to particles passage, such as cell debris, through pores ranging from 1 to 4 µm. In addition, successful chromatography column plugging mitigation was achieved by employing depth filtration before the chromatographic step. Depth filtration volumetric throughputs were between 600 and 1,000 L/m2. Combing a macroporous cell retention device with a depth filter not only provided an alternative to address the challenge of undesired long protein residence times in the bioreactor due to product sieving decay, but also exhibited a throughput increase, making the integration of multicolumn capture chromatography with a perfusion cell culture a more robust process.
Multifunctional Glycoconjugates for Recruiting Natural Antibodies against Cancer Cells
Authors: Liet Benjamin , Laigre Eugénie , Goyard David , Todaro Biagio , Tiertant Claire , Boturyn Didier , Berthet Nathalie , Renaudet Olivier 
Published: October 2019

AbstractWe have developed a fully synthetic and multifunctional antibody‐recruiting molecule (ARM) to guide natural antibodies already present in the blood stream against cancer cells without pre‐immunization. Our ARM is composed of antibody and tumor binding modules (i.e., ABM and TBM) displaying clustered rhamnose and cyclo‐RGD, respectively. By using a stepwise approach, we have first demonstrated the importance of multivalency for efficient recognition with naturel IgM and αvβ3 integrin expressing M21 tumor cell line. Once covalently conjugated by click chemistry, we confirmed by flow cytometry and confocal microscopy that the recognition properties of both the ABM and TBM are conserved, and more importantly, that the resulting ARM promotes the formation of a ternary complex between natural IgM and cancer cells, which is required for the stimulation of the cytotoxic immune response in vivo. Due to the efficiency of the synthetic process, a larger diversity of heterovalent ligands could be easily explored by using the same multivalent approach and could open new perspectives in this field.
Triple‐Bond Directed Csp2−N Bond Formation with N‐Fluorobenzenesulfonimide as Aminating Source: One‐Step Transformation of Aldehydes into Amines
Authors: Sushmita  , Aggarwal Trapti , Shibata Norio , Verma Akhilesh K. 
Published: October 2019

AbstractA metal‐free, versatile triple‐bond directed approach for the decarbonylative C−H amination of ortho‐alkynyl quinoline/pyridine aldehydes using N‐fluorobenzenesulfonimide as nitrogen source under mild reaction conditions has been described. The designed reaction strategy was triggered by trapping of fluorine by base with subsequent attack of bis(phenylsulfonyl)‐λ2‐azane on the carbonyl carbon of a heterocycle, which was gradually converted into the corresponding amine through a Curtius type rearrangement. This protocol provides a one‐step approach for the conversion of aldehydes into amines in good yields. The synthesized amines were successfully transformed into biologically important pyrroloquinolines/pyridines.
A measure to assess the workplace well‐being of psychological practitioners
Authors: Summers Elisabeth M.A. , Morris Reg C. , Bhutani Gita E. 
Published: October 2019

AbstractThe well‐being of psychological practitioners is a key factor in the effective delivery of psychological therapies and the effectiveness of mental health services. Despite this, there are no measures of well‐being for this professional group. The 26‐item psychological practitioner workplace well‐being measure (PPWWM) measures psychological well‐being for psychological practitioners and was informed by a qualitative study. Items were generated and then verified by groups of practitioners using sorting tasks. The items reflect a broad range of issues relevant to the workplace well‐being of psychological practitioners.The PPWWM was validated with a sample of 400 psychological practitioners recruited through professional networks. Internal consistency (α = .92) and test–retest reliability (r = .94) were high. Construct validity was indicated by positive correlations with the Health and Safety Executive Management Standards Indicator Tool and Satisfaction with Life Scale and negative correlation with the General Health Questionnaire. Exploratory factor analysis produced six factors, explaining 61.2% of the variance: professional and organizational; support and flexibility; professional role; physical environment; clinical supervision; and external personal. PPWWM scores were not significantly associated with a range of demographic variables (gender, health/disability, profession, and type of organization), but it did correlate significantly and negatively with age.The PPWWM has potential application as a brief measure, suitable for large‐scale surveys that specifically measures workplace well‐being in psychological practitioners. Future research could include cross validation with new samples and validation with subgroups of psychological practitioners.