bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacological Investigation of Serial Anxiety Tests in the Mouse: A Pilot Study
Authors: Umarudeen A. M. , Magaji M. G. , Bello O. S. , Aminu C. , Abdullahi M. I.
Published: May 2020

The use of test batteries has been suggested as a means to enhance throughput, to broaden the spectrum of anxiety parameters detectable and to minimise the numbers of experimental animals required in behavioural studies. This study was undertaken to determine the sensitivity of test batteries each of open field, zero mazes and staircase tests to anxiety behaviours in randomised mouse groups. Mice (n = 8) were exposed to these apparatuses serially in that order, thirty minutes following intraperitoneal administration of distilled water, 0.5 and 1.0 mg/kg diazepam.  Each mouse was allowed to spend 5 minutes to freely explore each test apparatus.  The results showed diazepam-treated mice exhibited significantly (p<0.05) reduced anxiety behaviours compared to the placebo group on most rodent anxiety parameters evaluated. The findings of this study suggest these behavioural test apparatuses, when used in serial combination, are sensitive and reliable to measure murine anxiety-related behaviours and the anxiolytic effects of standard/putative agents.
Environmental Liability Estimates and Equity Value of Oil Firms in Nigeria
Authors: Chukwu Gospel J. , Idamoyibo Hwerien Rosemary , Akunna Monday M.
Published: June 2020

The purpose of this study is to examine whether decommissioning and environmental restoration estimates affect equity valuation of oil firms in Nigeria. The study also examined whether changes in these environmental liability estimates are value relevant in Nigeria. The study analysed data from four listed oil firms that estimated and reported decommissioning liabilities in their annual reports from 2012 to 2018, using regression analysis technique. Findings indicate that investors in Nigeria’s oil and gas firms negatively value environmental liability estimates. This finding is possibly because Nigerian investors view these estimates as representing the extent to which the firm will damage the environment. Given the adverse effect of environmental degradation in Nigeria, investors are wary of any indication of environmental violation. However, changes in decommissioning and restoration estimates are not associated with variations in the market value of oil firms in Nigeria, probably due to lack of investors’ sophistication in appreciating the basis for these changes. Further, some listed oil firms did not provide for environmental liability in their annual reports for the seven years examined, possibly because there is no legal obligation to restore the environment. These findings should motivate environmental regulators in Nigeria to consider laws that will expressly mandate environmental restoration for polluting firms in the country. With such legal requirement, accounting regulators could ensure that oil firms (with facilities that affect the environment) recognise provision for environmental liabilities in their financial statements.
Forecasting Solar PV Demand Split and Fuel Wood Usage Reduction in Eriti and Oke-Agunla Villages in Nigeria
Authors: Jesuleye Olalekan Aquila
Published: May 2020

The study examined solar photovoltaic demand split and fuel wood usage reduction in Eriti and Oke-Agunla villages, that were among the pilot sites for solar electrification programs in the western ecological region of Nigeria. It used questionnaire techniques to elicit information in the local dialect of the respondents, on alternative energy sources for provision of energy services from each of the household's heads, representing solar PV users, in all the 371 households that constitute about 13.4 percent of the 2,778 dwellers in the two villages, for the base year 2020. Specifically, at the rate of the observed 8 dwellers per household, data were obtained from 179 respondents, out of a total of 1,434 dwellers in Eriti village. Likewise, at the rate of the observed 7 dwellers per household, data were also obtained from 192 respondents, out of a total of 1,344 dwellers in Oke-Agunla village. Model for Analysis of Energy Demand (MADE-II) was used for the study. The study showed that the total lighting demand share for solar PV in each of the villages’ total energy demand mix in 2020 was insignificantly low at 5.1 percent share in Eriti village and 6.1 percent share in Oke-Agunla village. Contrariwise, firewood demand maintained as high as 94 and 92 percent share for Eriti and Oke-Agunla villages respectively in the total energy demand mix and by 2030, in Oke-Agunla village, 3-stones-firewood stoves demand for cooking fell drastically from 77% to 30% share, whereas improved firewood stoves demand for cooking rose astronomically from 11% share in 2020 to 45% share by 2030. Nigerian government should adopt such best policy intervention scenario for all the rural areas in the country.
Correlations of Major Flame Characteristics of Some Fire Tolerant Trees in South-East Nigeria by Coefficient of Determination (R2)
Authors: Okafor Vincent Nwalieji , Obiadi Matthew Chiemezie , Obiefuna Joy Ngozika
Published: May 2020

Background: Bush fire is a common hazard in South East-Nigeria as in other parts of the country during the harmattan. Every year, thousands of hectares of forests as well as suburban lands are severely burnt. These forest fires have been catastrophic, destroying large areas of tropical rain forests and in most cases have claimed many lives and destroyed properties worth millions of naira. However, some of these trees identified by local people and named by taxonomists as Daniellia oliveri, Anacadium occidentale, Vitex doniana, Lonchocarpus griffonianus, Gmelina arborea, Nauclea latifolia, Tectona grandis, Mangifera indica, Delonix regia, Newbouldia laevis, Azadirachta indica, Dialium guineense, Terminalia superba, Manilkara obovata and Irvingia gabonensis have proven to be fire tolerant.

Aim: The aim is to establish correlations among the physical properties (wood density and moisture content) and flame characteristics (ignition time, flame propagation rate, flame duration, afterglow time, ash formation and limiting oxygen index) of these fire tolerant trees.

Study Design: An item structured instrument was developed by the researchers which reflected the six points modified Likert scale of strongly agree, agree, somewhat agree, somewhat disagree, disagree, strongly disagree and used to elicit information from the respondents who were mainly seasoned wood dealers of above 60 years of age. Analysis of Variance (ANOVA) was the major tool of analysis used to establish whether the tree species tolerates fire or not while correlation of the parameters was achieved by the application of R2.

Place and Duration of Study: Determination of both the physical properties and flame characteristics of the tree species was done at the Research Laboratory of the Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University, Awka between June, 2018 and April, 2019.

Methodology: The physical properties of the tree species as well as their flame characteristics were carried out using their standard methods.

Results: The values for these parameters vary among the tree species. Correlation among the parameters indicates a determination coefficient range from 0.000 to 0.637.

Conclusion: There are highly significant correlations between wood density and both ignition time and flame propagation rate as well as wood density and limiting oxygen index. There is also strong correlation between ignition time and both flame propagation rate and limiting oxygen index. Afterglow time depends on limiting oxygen index and vice versa.
The Effects of Dark Energy on Gravitation
Authors: Eziyi Emea Ajike , Obinwa Orji , Chinwekele Nwasuka Stanley , ASO Jonah Ndukwe , Chiedozie Friday
Published: May 2020

Dark energy is thought to be very homogenous, not very dense and it is not known to interact through any of the fundamental forces other than gravity. In this research work, we use analytical method to find a model that may possibly relate dark energy to gravitation. After some plausible analyses, we obtain a relation,   

where µ is Gravitational potential energy,  is the mass of galaxy,  is mass of earth, Λ is dark energy,  is receding velocity,  is Hubble’s constant and Ro  is the distance measured from the point of observation and the galaxy. Moreover, we estimate K =  for various galaxies, finally, the relation µ ∝ Λ, indicates a direct relationship between Dark energy and Gravitation.
Analysis of the structure and substrate scope of chitooligosaccharide oxidase reveals high affinity for C2‐modified glucosamines
Authors: Savino Simone , Jensen Sonja , Terwisscha van Scheltinga Anke , Fraaije Marco W.
Published: June 2020

Chitooligosaccharide oxidase (ChitO) is a fungal carbohydrate oxidase containing a bicovalently bound FAD cofactor. The enzyme is known to catalyse the oxidation of chitooligosaccharides, oligomers of N‐acetylated glucosamines derived from chitin degradation. In this study, the unique substrate acceptance was explored by testing a range of N‐acetyl‐d‐glucosamine derivatives, revealing that ChitO preferentially accepts carbohydrates with a hydrophobic group attached to C2. The enzyme also accepts streptozotocin, a natural product used to treat tumours. Elucidation of the crystal structure provides an explanation for the high affinity towards C2‐decorated glucosamines: the active site has a secondary binding pocket that accommodates groups attached at C2. Docking simulations are fully in line with the observed substrate preference. This work expands the knowledge on this versatile enzyme.
Trajectories of Structural Disease Progression in Knee Osteoarthritis
Authors: Collins Jamie E. , Neogi Tuhina , Losina Elena
Published: June 2020

Objective

Knee osteoarthritis (OA) is a heterogeneous disease, with most patients experiencing slow disease progression and some with rapid deterioration. We aimed to identify groups of patients with symptomatic knee OA experiencing rapid structural progression.

Methods

We selected participants from the Osteoarthritis Initiative with baseline Kellgren/Lawrence (K/L) grades 1–3 and knee pain, and with joint space width (JSW) on fixed‐flexion knee radiographs assessed at baseline and with ≥1 follow‐up over 8 years. We used latent class growth analysis to identify subgroups of JSW progression, jointly modeling time to knee replacement (KR) to account for potential informative dropouts. After identifying trajectories, we used logistic regression to assess the association between baseline characteristics and the JSW trajectory group.

Results

We used data from 1,578 participants. Baseline radiographic severity was K/L grade 1 in 17%, K/L grade 2 in 50%, and K/L grade 3 in 33%. We identified 3 distinct JSW trajectories: 86% stable, 6% with stable JSW followed by late progression, and 8% with early progression. Incorporating information about KR resulted in 47% of KRs initially classified as stable being reclassified to 1 of the progressing trajectories. Prior knee surgery was associated with being in the late‐progressing versus the stable trajectory, while obesity was associated with being in the early‐progressing versus stable trajectory.

Conclusion

In addition to a subgroup of individuals experiencing early structural progression, 8‐year longitudinal data allowed the identification of a late‐progressing trajectory. Incorporating information about KR was important to properly identify longitudinal structural trajectories in knee OA.
A New Method to Increase the Spheroidization Rate of Lamellar α Microstructure during Hot Deformation of a Ti–6Al–4V Alloy
Authors: Jiang Yu-Qiang , Lin Y. C. , Zhao Chun-Yang , Chen Ming-Song , He Dao-Guang
Published: June 2020

Ti–6Al–4V is one of the important materials for manufacturing critical components of aero‐engines. The excellent service properties of aero‐engines are dependent on components and their material microstructures. The spheroidization of a lamellar α microstructure is one of the important methods to refine grains in Ti alloys. Herein, a new method is proposed to increase the spheroidization rate of the lamellar α microstructure during hot deformation of a Ti–6Al–4V alloy. The spheroidization behaviors of the lamellar α microstructure are investigated by one‐pass and two‐pass hot compression tests. A special spheroidization behavior, which is defined as metadynamic spheroidization, is found during inter‐pass; i.e., the lamellar α phase breaks up during the inter‐pass due to the migration and transformation of sub‐boundaries. The spheroidization rate of the lamellar α phase is increased by the metadynamic spheroidization mechanism. The effects of inter‐pass holding time, pre‐strain, and total strain on the spheroidization rate are obvious. Furthermore, the spheroidization rate of lamellar α phases by two‐pass compression is approximately 30% higher than that by one‐pass compression for a given total strain of 1.2. In addition, the strains for the completed spheroidization can be effectively reduced by two‐pass isothermal compression.
Organoid Polymer Functionality and Mode of Klebsiella pneumoniae Membrane Antigen Presentation Regulates Ex Vivo Germinal Center Epigenetics in Young and Aged B Cells
Authors: Graney Pamela L. , Lai Kristine , Post Sarah , Brito Ilana , Cyster Jason , Singh Ankur
Published: June 2020

Antibiotic‐resistant bacteria are a major global health threat that continues to rise due to a lack of effective vaccines. Of concern are Klebsiella pneumoniae (K. pneumoniae) that fail to induce in vivo germinal center B cell responses, which facilitate antibody production to fight infection. Immunotherapies using antibodies targeting antibiotic‐resistant bacteria are emerging as promising alternatives, however, they cannot be efficiently derived ex vivo, necessitating the need for immune technologies to develop therapeutics. Here, polyethylene glycol (PEG)‐based immune organoids are developed to elucidate the effects of polymer end‐point chemistry, integrin ligands, and mode of K. pneumoniae antigen presentation on germinal center‐like B cell phenotype and epigenetics, to better define the lymph node microenvironment factors regulating ex vivo germinal center dynamics. Notably, PEG vinyl sulfone or acrylate fail to sustain primary immune cells, but functionalization with maleimide (PEG‐4MAL) leads to B cell expansion and germinal center‐like induction. RNA sequencing analysis of lymph node stromal and germinal center B cells shows niche associated heterogeneity of integrin‐related genes. Incorporation of niche‐mimicking peptides reveals that collagen‐1 promotes germinal center‐like dynamics and epigenetics. PEG‐4MAL organoids elucidate the impact of K. pneumoniae outer membrane‐embedded protein antigen versus soluble antigen presentation on germinal centers and preserve the response across young and aged mice.
Flexible and Transparent Metal Oxide/Metal Grid Hybrid Interfaces for Electrophysiology and Optogenetics
Authors: Chen Zhiyuan , Yin Rose T. , Obaid Sofian N. , Tian Jinbi , Chen Sheena W. , Miniovich Alana N. , Boyajian Nicolas , Efimov Igor R. , Lu Luyao
Published: June 2020

Flexible and transparent microelectrodes and interconnects provide the unique capability for a wide range of emerging biological applications, including simultaneous optical and electrical interrogation of biological systems. For practical biointerfacing, it is important to further improve the optical, electrical, electrochemical, and mechanical properties of the transparent conductive materials. Here, high‐performance microelectrodes and interconnects with high optical transmittance (59–81%), superior electrochemical impedance (5.4–18.4 Ω cm2), and excellent sheet resistance (5.6–14.1 Ω sq−1), using indium tin oxide (ITO) and metal grid (MG) hybrid structures are demonstrated. Notably, the hybrid structures retain the superior mechanical properties of flexible MG other than brittle ITO with no changes in sheet resistance even after 5000 bending cycles against a small radius at 5 mm. The capabilities of the ITO/MG microelectrodes and interconnects are highlighted by high‐fidelity electrical recordings of transgenic mouse hearts during co‐localized programmed optogenetic stimulation. In vivo histological analysis reveals that the ITO/MG structures are fully biocompatible. Those results demonstrate the great potential of ITO/MG interfaces for broad fundamental and translational physiological studies.
Enhancing the Efficacy of Metal‐Free MRI Contrast Agents via Conjugating Nitroxides onto PEGylated Cross‐Linked Poly(Carboxylate Ester)
Authors: Guo Shiwei , Wang Xiaoming , Dai Yan , Dai Xinghang , Li Zhiqian , Luo Qiang , Zheng Xiuli , Gu Zhongwei , Zhang Hu , Gong Qiyong , Luo Kui
Published: June 2020

Herein, two water‐soluble PROXYL‐based magnetic resonance imaging (MRI) macromolecular organic contrast agents (mORCAs) are designed and synthesized: linear and cross‐linked PCE‐mPEG‐Ppa‐PROXYL. They are prepared by conjugating linear and cross‐linked poly(carboxylate ester) (PCE) with poly(ethylene glycol) (mPEG2000)‐modified nitroxides (PROXYL), respectively. Both mORCAs form self‐assembled aggregates in an aqueous phase and PROXYL is protected inside a hydrophobic core to achieve great resistance to reduction in the physiological environment, and they have low toxicity. Since cross‐linked PCE‐mPEG‐Ppa‐PROXYL possess a branched architecture, its self‐assembled aggregate is more stable and compact with a greater particle size. Cross‐linked PCE‐mPEG‐Ppa‐PROXYL outperform the linear one in the following aspects: 1) its longitudinal relaxivity (r1 = 0.79 mm−1 s−1) is higher than that of the linear one (r1 = 0.64 mm−1 s−1) and both excel the best mORCA reported so far (r1 = 0.42 mm−1 s−1); 2) its blood retention time (≈48 h) is longer than that of its linear counterpart (≈10 h); 3) cross‐linked PCE‐mPEG‐Ppa‐PROXYL provided better MR imaging contrast resolution in normal organs (liver and kidney) and tumor of mice than the linear one. Overall, cross‐linked PCE‐mPEG‐Ppa‐PROXYL may have great potential to be a novel metal‐free macromolecular contrast agent for MR imaging.
Availability of Emergency Medicine Away Rotations
Authors: Kiemeney Michael , Franzen Doug
Published: June 2020

Objectives

Residency directors in emergency medicine (EM) have been placing increased value on the Standardized Letter of Evaluation to evaluate the escalating numbers of residency applications received each year. This has placed added significance on EM away rotations (ARs). We sought to determine the overall availability of ARs in EM.

Methods

We surveyed clerkships sites at the end of 2018–2019 application season. The survey requested data about maximum rotation spots available, actual number of students that rotated, and data about application processing and rotation offer decision making.

Results

We received 190 responses, of which 129 (49% of 262 clerkship sites surveyed) provided data regarding available positions and student rotators. A total of 3,472 ARs were completed at the responding sites. The average capacity ratio (CR; maximum available AR spots divided by AR completed by students) for responding sites was 1.57. AR availability varied by time and geography. Most AR positions were filled during peak season (CR = 1.22); however, many went unfilled outside of this time frame (CR = 2.41). Geographic data showed some locations had significant unfilled AR availability.

Conclusions

Our survey data show that there are at least 1.5 AR positions per applicant. Students can be reasonably expected to complete one AR and, in select cases, a second. CR during peak season indicates nearly saturated AR positions. Flexibility of rotation timing and tools to link open AR positions with students needing to complete a rotation will help optimize filling available AR positions. Continued effort in application advising from home clerkships and processes to ensure equitable distribution of AR positions among students will help ensure interested students obtain a position.
Epigenetic and transcriptomic consequences of excess X‐chromosome material in 47,XXX syndrome—A comparison with Turner syndrome and 46,XX females
Authors: Nielsen Morten Muhlig , Trolle Christian , Vang Søren , Hornshøj Henrik , Skakkebæk Anne , Hedegaard Jakob , Nordentoft Iver , Pedersen Jakob Skou , Gravholt Claus Højbjerg
Published: June 2020

47,XXX (triple X) and Turner syndrome (45,X) are sex chromosomal abnormalities with detrimental effects on health with increased mortality and morbidity. In karyotypical normal females, X‐chromosome inactivation balances gene expression between sexes and upregulation of the X chromosome in both sexes maintain stoichiometry with the autosomes. In 47,XXX and Turner syndrome a gene dosage imbalance may ensue from increased or decreased expression from the genes that escape X inactivation, as well as from incomplete X chromosome inactivation in 47,XXX. We aim to study genome‐wide DNA‐methylation and RNA‐expression changes can explain phenotypic traits in 47,XXX syndrome. We compare DNA‐methylation and RNA‐expression data derived from white blood cells of seven women with 47,XXX syndrome, with data from seven female controls, as well as with seven women with Turner syndrome (45,X). To address these questions, we explored genome‐wide DNA‐methylation and transcriptome data in blood from seven females with 47,XXX syndrome, seven females with Turner syndrome, and seven karyotypically normal females (46,XX). Based on promoter methylation, we describe a demethylation of six X‐chromosomal genes (AMOT, HTR2C, IL1RAPL2, STAG2, TCEANC, ZNF673), increased methylation for GEMIN8, and four differentially methylated autosomal regions related to four genes (SPEG, MUC4, SP6, and ZNF492). We illustrate how these changes seem compensated at the transcriptome level although several genes show differential exon usage. In conclusion, our results suggest an impact of the supernumerary X chromosome in 47,XXX syndrome on the methylation status of selected genes despite an overall comparable expression profile.
Atroposelective Synthesis of Axially Chiral N‐Arylpyrroles by Chiral‐at‐Rhodium Catalysis
Authors: Ye Chen‐Xi , Chen Shuming , Han Feng , Xie Xiulan , Ivlev Sergei , Houk K. N. , Meggers Eric
Published: June 2020

A transformation of fluxional into configurationally stable axially chiral N‐arylpyrroles was achieved with a highly atroposelective electrophilic aromatic substitution catalyzed by a chiral‐at‐metal rhodium Lewis acid. Specifically, N‐arylpyrroles were alkylated with N‐acryloyl‐1H‐pyrazole electrophiles in up to 93 % yield and with up to >99.5 % ee, and follow‐up conversions reveal the synthetic utility of this new method. DFT calculations elucidate the origins of the observed excellent atroposelectivity.
How To Make Nitroaromatic Compounds Glow: Next‐Generation Large X‐Shaped, Centrosymmetric Diketopyrrolopyrroles
Authors: Skonieczny Kamil , Papadopoulos Ilias , Thiel Dominik , Gutkowski Krzysztof , Haines Philipp , McCosker Patrick M. , Laurent Adèle D. , Keller Paul A. , Clark Timothy , Jacquemin Denis , Guldi Dirk M. , Gryko Daniel T.
Published: June 2020

Red‐emissive π‐expanded diketopyrrolopyrroles (DPPs) with fluorescence reaching λ=750 nm can be easily synthesized by a three‐step strategy involving the preparation of diketopyrrolopyrrole followed by N‐arylation and subsequent intramolecular palladium‐catalyzed direct arylation. Comprehensive spectroscopic assays combined with first‐principles calculations corroborated that both N‐arylated and fused DPPs reach a locally excited (S1) state after excitation, followed by internal conversion to states with solvent and structural relaxation, before eventually undergoing intersystem crossing. Only the structurally relaxed state is fluorescent, with lifetimes in the range of several nanoseconds and tens of picoseconds in nonpolar and polar solvents, respectively. The lifetimes correlate with the fluorescence quantum yields, which range from 6 % to 88 % in nonpolar solvents and from 0.4 % and 3.2 % in polar solvents. A very inefficient (T1) population is responsible for fluorescence quantum yields as high as 88 % for the fully fused DPP in polar solvents.
Ineffective OH Pinning of the Flipping Dynamics of a Spherical Guest within a Tight‐Fitting Tube
Authors: Matsuno Taisuke , Someya Maki , Sato Sota , Maeda Satoshi , Isobe Hiroyuki
Published: June 2020

A supramolecular/synthetic method has been devised to affix a sterically hindered substituent onto a fullerene guest encapsulated in a tubular host. A two‐wheeled complex of (C59N)‐(C59N) with a tubular host was oxidatively bisected to afford a C59N+ cation captured in the tube. The C59N+ cation in the tube was then trapped by ethanol or water, which led to an oxy substituent pinned on the guest. The guest motions within the tube were modulated by the pinned substituent, and up‐and‐down flipping motions were halted by an ethoxy substituent. A hydroxy substituent, however, was ineffective in halting the flipping motions, despite the tight‐fitting relationship between the tubular host and the spherical guest. Theoretical calculations of the dynamics revealed that the flipping motions were assisted by OH‐π hydrogen bonds between the guest and the carbon‐rich wall and that sliding motions of the OH group were also facilitated by deformations of the tube.
Cation‐Controlled Assembly of Polyoxotungstate‐Based Coordination Networks
Authors: Chen Linfeng , Turo Michael J. , Gembicky Milan , Reinicke Ruth A. , Schimpf Alina M.
Published: June 2020

The Preyssler polyoxoanion, [NaP5W30O110]14− ({P5W30}), is used as a platform for evaluating the role of nonbridging cations in the formation of transition‐metal‐bridged polyoxometalate (POM) coordination frameworks. Specifically, the assembly architecture of Co2+‐bridged frameworks is shown to be dependent on the identity and amount of alkali or alkaline‐earth cations present during crystallization. The inclusion of Li+, Na+, K+, Mg2+, or Ca2+ in the framework synthesis is used to selectively synthesize five different Co2+‐bridged {P5W30} structures. The influence of the competition between K+ and Co2+ for binding to {P5W30} in dictating framework assembly is evaluated. The role of ion pairing on framework assembly structure and available void volume is discussed. Overall, these results provide insight into factors governing the ability to achieve controlled assembly of POM‐based coordination networks.
Chemie freier Radikale von Phosphasilenen
Authors: Samedov Kerim , Heider Yannic , Cai Yuanjing , Willmes Philipp , Mühlhausen Daniel , Huch Volker , West Robert , Scheschkewitz David , Percival Paul W.
Published: June 2020

Das Verständnis der Eigenschaften von Radikalen, die ausgehend von Si‐haltigen, schweren Analoga von Alkenen gebildet werden, ist wichtig für ihre Anwendung in der radikalischen Polymerisation. Sterische und elektronische Substituenteneffekte in Phosphasilenen stabilisieren nicht nur die Si=P‐Doppelbindung, sondern beeinflussen auch die Struktur und Natur der gebildeten Radikale. Wir berichten hier über Untersuchungen an Phosphasilen‐abgeleiteten Radikalen mit Mes‐, Tip‐, Dur‐ und NMe2‐Substituenten am P‐Atom mithilfe von Myonenspinspektroskopie und DFT‐Rechnungen. Die Addition von Myonium (einem leichten Isotop von Wasserstoff) an Phosphasilene zeigt, dass a) das Elektronendonor‐NMe2‐ und das sperrigste Tip‐substituierte Phosphasilen mehrere myonierte Radikale mit unterschiedlichen Rotamer‐Konformationen bilden; b) das sperrige Dur‐substituierte Phosphasilen zwei Radikale (Si‐ und P‐zentriert) bildet; und c) Mes‐substituiertes Phosphasilen hauptsächlich eine Radikalspezies am P‐Zentrum bildet. Diese signifikanten Unterschiede rühren von einem intramolekularen Substituenteneffekt her.
Scalable Photoelectrochemical Dehydrogenative Cross‐Coupling of Heteroarenes with Aliphatic C−H Bonds
Authors: Xu Pin , Chen Peng‐Yu , Xu Hai‐Chao
Published: June 2020

Heteroarenes are structural motifs found in many bioactive compounds and functional materials. Dehydrogenative cross‐coupling of heteroarenes with aliphatic C−H bonds provides straightforward access to functionalized heteroarenes from readily available materials. Established methods employ stoichiometric chemical oxidants under conditions of heating or light irradiation. By merging electrochemistry and photochemistry, we have achieved efficient photoelectrochemical dehydrogenative cross‐coupling of heteroarenes and C(sp3)−H donors through H2 evolution, without the addition of metal catalysts or chemical oxidants. Mechanistically, the C(sp3)−H donor is converted to a nucleophilic carbon radical through H‐atom transfer with chlorine atom, which is produced by light irradiation of anodically generated Cl2 from Cl−. The carbon radical then undergoes radical substitution to the heteroarene to afford alkylated heteroarene products.
Feasibility of foam forming technology for producing wood plastic composites
Authors: Immonen Kirsi , Jetsu Petri , Keränen Janne , Torvinen Katariina
Published: June 2020

Cellulose fiber‐containing thermoplastic composite materials are being used in an increasing number of applications produced typically by injection molding and extrusion processing methods. One potential way to manufacture thermoplastic cellulosic fiber composites is foam forming technology developed originally for paper manufacturing. This article compares the low‐density polyethylene (LDPE) and unrefined northern bleached softwood kraft pulp (NBSKP) composite materials prepared with foam forming, extrusion, and injection molding. The results show that the foam forming enabled three times higher Charpy impact strength properties and 68% higher tensile modulus compared to injection molded 30% NBSKP fiber‐containing LDPE composites without changes in composite color. Foam forming is a potential large‐scale manufacturing method for thermoplastic composite sheets used, for example, in compression molding or thermoforming.
Synthesis of amino‐cosubstituted polyorganophosphazenes and fabrication of their nanoparticles for anticancer drug delivery
Authors: Khan Rizwan Ullah , Yu Haojie , Wang Li , Teng Lisong , Zain‐ul‐Abdin  , Nazir Ahsan , Fahad Shah , Elshaarani Tarig , Haq Fazal , Shen Di
Published: June 2020

The development of safe drug carriers is cardinal in cancer therapy, which can target the cancer cells and release the loaded drug on‐demand without damaging the healthy cells of the body. In our work, we synthesized three different biodegradable polymers, poly[(ethyl aminobezoate) (ethyl glycinato) phosphazenes] (PABGPs), in different mole ratio of side groups. The successful synthesis of these PABGPs was confirmed by 1H NMR, 31P NMR, FT‐IR, and gel permeation chromatography. These PABGPs were fabricated into drug (camptothecin, CPT, a hydrophobic anticancer drug) loaded nanoparticles. These drug‐loaded nanoparticles showed good drug release behaviors under normal physiological conditions (pH 7.4 and temperature 37°C). These PABGPs‐based nanoparticles may find their application as effective drug carriers for cancer therapy.
Tribological characterization of graphene nanoplatelets/alumina particles filled epoxy hybrid nanocomposites
Authors: Kesavulu A. , Mohanty Akash
Published: June 2020

In this work, graphene nanoplatelets have been synthesized using liquid phase exfoliation of graphite flake powder. The exfoliated graphene nanoplatelets were identified and characterized by using UV–Visible–NIR spectroscopy, High resolution transmission electron microscopy, electron diffraction, scanning electron microscopy and X‐ray diffraction. The obtained graphene nanoplatelets and nano alumina at various weight ratios were dispersed in an epoxy matrix to enhance the surface roughness (Ra), micro hardness (Hv) and coefficient of friction (CoF) of epoxy hybrid nanocomposites. The results showed that the Ra and CoF value for the combined loading of 0.2 wt% of graphene nanoplatelets and 0.8 wt% of alumina into the epoxy was decreased to 41.02 and 20.01% whereas, the Hv value was increased to 10.04% when compared with the neat epoxy. The improved mechanical and tribological behaviors are suitable for the applications bearing and coating.
Social justice education with Chinese characteristics: An example from Shanghai
Authors: Tan Charlene
Published: June 2020

This article analyses a Chinese approach to social justice in education using the example of Shanghai. In addressing schooling inequalities, Shanghai illustrates social justice education with Chinese characteristics, which revolves around the ideal of ‘educational balance’ (jiaoyu junheng). The ‘balance’ in question is about achieving a values‐centred and all‐round education in and across all schools through the cultivation of a school’s ‘inner quality’ (neihan). This Chinese formulation of social justice education is manifested through two representative policy measures: creating and strengthening ‘new high‐quality schools’ and helping weak schools to level up. The Chinese characteristics of these action plans are seen in two ways: a focus on social justice between schools rather than between students; and an emphasis on the moral cultivation of students. It is argued that a Chinese model of social justice education promotes educational equity to some extent through the politics of redistribution, recognition and representation. However, a major critique is its hegemonic and top‐down nature, which overlooks alternative and competitive voices—especially those of migrant children—as part of a politics of representation.
Production of Substituted Styrene Bioproducts from Lignin and Lignocellulose Using Engineered Pseudomonas putida KT2440
Authors: Williamson James J. , Bahrin Nurfariza , Hardiman Elizabeth M. , Bugg Timothy D. H.
Published: June 2020

Ferulic acid is a renewable chemical found in lignocellulose from grasses such as wheat straw and sugarcane. Pseudomonas putida is able to liberate and metabolize ferulic acid from plant biomass. Deletion of the hydroxycinnamoyl‐CoA hydratase‐lyase gene (ech) produced a strain of P. putida unable to utilize ferulic and p‐coumaric acid, which is able to accumulate ferulic acid and p‐coumaric acid from wheat straw or sugar cane bagasse. Further engineering of this strain saw the replacement of ech with the phenolic acid decarboxylase padC, which converts p‐coumaric and ferulic acid into 4‐vinylphenol and the flavor agent 4‐vinylguaiacol, respectively. The engineered strain containing padC is able to generate 4‐vinylguaiacol and 4‐vinylphenol from media containing lignocellulose or Green Value Protobind lignin as feedstock, and does not require the addition of an exogenous inducer molecule. Biopolymerization of 4‐vinylguaiacol and 4‐vinylcatechol styrene products is also carried out, using Trametes versicolor laccase, to generate “biopolystyrene” materials on small scale.
Breast cancer surgery in older women: outcomes of the Bridging Age Gap in Breast Cancer study
Authors: Morgan J L , George J , Holmes G , Martin C , Reed M W R , Ward S , Walters S J , Cheung K Leung , Audisio R A , Wyld L
Published: June 2020

Background

Breast cancer surgery in older women is variable and sometimes non-standard owing to concerns about morbidity. Bridging the Age Gap in Breast Cancer is a prospective multicentre cohort study aiming to determine factors influencing treatment selection and outcomes from surgery for older patients with breast cancer.

Methods

Women aged at least 70 years with operable breast cancer were recruited from 57 UK breast units between 2013 and 2018. Associations between patient and tumour characteristics and type of surgery in the breast and axilla were evaluated using univariable and multivariable analyses. Oncological outcomes, adverse events and quality-of-life (QoL) outcomes were monitored for 2 years.

Results

Among 3375 women recruited, surgery was performed in 2816 patients, of whom 24 with inadequate data were excluded. Sixty-two women had bilateral tumours, giving a total of 2854 surgical events. Median age was 76 (range 70–95) years. Breast surgery comprised mastectomy in 1138 and breast-conserving surgery in 1716 procedures. Axillary surgery comprised axillary lymph node dissection in 575 and sentinel node biopsy in 2203; 76 had no axillary surgery. Age, frailty, dementia and co-morbidities were predictors of mastectomy (multivariable odds ratio (OR) for age 1·06, 95 per cent c.i. 1·05 to 1·08). Age, frailty and co-morbidity were significant predictors of no axillary surgery (OR for age 0·91, 0·87 to 0·96). The rate of adverse events was moderate (551 of 2854, 19·3 per cent), with no 30-day mortality. Long-term QoL and functional independence were adversely affected by surgery.

Conclusion

Breast cancer surgery is safe in women aged 70 years or more, with serious adverse events being rare and no mortality. Age, ill health and frailty all influence surgical decision-making. Surgery has a negative impact on QoL and independence, which must be considered when counselling patients about choices.
Proof of surgical publication prowess: prospective observational study of factors associated with surrogate markers of academic reach
Authors: Robinson D B T , Powell A G M T , Hopkins L , James O P , Abdelrahman T , Egan R , Lewis W G
Published: June 2020

Background

In the UK, general surgery higher surgical trainees (HSTs) must publish at least three peer-reviewed scientific articles (as first, second or corresponding author) to qualify for certification of completion of training (CCT). This study aimed to identify the factors associated with success in this arena.

Methods

Deanery rosters supplemented with data from the Intercollegiate Surgical Curriculum Programme, PubMed and ResearchGate were used to identify the profiles of consecutive HSTs. Primary outcomes were publication numbers at defined points in higher training (speciality training year (ST) 3–8); secondary outcomes were the Hirsch index and ResearchGate scores.

Results

Fifty-nine consecutive HSTs (24 women, 35 men) were studied. The median publication number was 3 (range 0–30). At least three published articles were obtained by 30 HSTs (51 per cent), with 19 (38 per cent) of 50 HSTs achieving this by ST4 (of whom 15 (79 per cent) had undertaken out of programme for research (OOPR) time) and 24 (80 per cent) by ST6. Thirteen HSTs (22 per cent) (ST3, 6; ST4, 4; ST5, 2; ST8, 1) had yet to publish at the time of writing. OOPR was associated with achieving three publications (24 of 35 (69 per cent) versus 6 of 24 (25 per cent) with no formal research time; P = 0·001), higher overall number of publications (median 6 versus 1 respectively; P < 0·001), higher ResearchGate score (median 23·37 versus 5·27; P < 0·001) and higher Hirsch index (median 3 versus 1; P < 0·001). In multivariable analysis, training grade (odds ratio (OR) 1·89, 95 per cent c.i. 0·01 to 3·52; P = 0·045) and OOPR (OR 6·55, 2·04 to 21·04; P = 0·002) were associated with achieving three publications.

Conclusion

If CCT credentials are to include publication profiles, HST programmes should incorporate research training in workforce planning.
Towards an integrated model for the transference of environmental responsibility
Authors: Gilal Faheem Gul , Gilal Naeem Gul , Channa Nisar Ahmed , Gilal Rehman Gul , Gilal Rukhsana Gul , Tunio Muhammad Nawaz
Published: June 2020

This research explores how environmental responsibility transfers to others. Although environmental responsibility is one of the most debated topics in environmental management literature, a framework describing how a teacher's environmental responsibility shapes the student's environmental responsibility is still lacking. Adopting emotional contagion theory as a lens, the paper addresses this issue via the mediation of emotional contagion and the moderation of a teacher's environmental concern. Based on a survey of teachers and students (N = 283) conducted in Pakistan, our findings provide evidence that a teacher's environmental responsibility can better transfer to students via emotional contagion. Additionally, our data establish that the transference of environmental responsibility from teachers to students via emotional contagion is more effective when the teacher has a high level of environmental concern than when he or she has a low level of environmental concern. Finally, the authors discuss the implications for policy in detail.
Nostalgia prompts sustainable product disposal
Authors: Wang Yan , Tian Hong , Sarigöllü Emine , Xu Wei
Published: June 2020

Consumers' product‐disposal behaviors impact the environment, businesses, society, and consumer well‐being. This research explores if and how consumers' disposal behaviors are influenced by sentiments of nostalgia. Four experimental studies are conducted, two on student samples and two on general population, to test our hypotheses. Study 1 shows that compared with collective nostalgia, personal nostalgia elicits higher intention to keep and reuse products. In contrast, collective nostalgia elicits higher intention to donate and recycle products. Both personal nostalgia and collective nostalgia reduce intention to throw away. Study 2 further corroborates the negative impact of personal nostalgia and collective nostalgia on throw away intention. Study 3 finds that the positive effect of personal nostalgia on keep and reuse intention is mediated by self‐continuity. Finally, study 4 demonstrates that collective efficacy mediates the positive effect of collective nostalgia on donate and recycle intention. This study has theoretical contributions and practical implications for scholars and policy makers.
Ansavaricin J, a New Heterocyclic Ring‐Fused Streptovaricin from Gene stvP5‐Deleted Mutant of Streptomyces spectabilis CCTCC M2017417
Authors: Liu Yuan‐Zhen , Chen Xu , Li Zheng‐Yuan , Huang Li–Xia , Sun Yu‐Hui
Published: June 2020

A new ring‐fused streptovaricin analogue, named ansavaricin J, was unprecedently isolated from the culture of the genetically modified strains ΔstvP5 which derived from Streptomyces spectabilis CCTCC M2017417. Its structure was elucidated via comprehensive spectroscopic analyses, including 1D‐ and 2D‐NMR tests, and HR‐ESI‐MS data analysis. Notably, ansavaricin J and E represent the only two reported examples of heterocyclic ring‐fused streptovaricins thus far, however, it only showed insignificant antibacterial activities against Staphylococcus aureus.
Resolution of bone, cutaneous, and muscular involvement after haploidentical hematopoietic stem cell transplantation followed by post‐transplant cyclophosphamide in adult T‐cell leukemia/lymphoma
Authors: Iioka Futoshi , Tanabe Hiroshi , Honjo Gen , Misaki Takashi , Ohno Hitoshi
Published: June 2020

Haploidentical hematopoietic stem cell transplantation followed by post‐transplant cyclophosphamide provides a well‐tolerated and potentially curable treatment for chemorefractory acute‐type adult T‐cell leukemia/lymphoma.
High Performance Hydrogen Evolution Reaction Catalyst Based on Single‐Walled Carbon Nanotubes Decorated by RuOx Nanoparticles
Authors: Fedorov Fedor S. , Settipani Daniel , Melandsø Buan Marthe Emelie , Sainio Jani , Ali Farhan S. M. , Ilatovskii Daniil , Kallio Tanja , Nasibulin Albert G.
Published: June 2020

We report a cathode material based on plasma‐treated single‐walled carbon nanotubes decorated by RuOx nanoparticles using atomic layer deposition. We have examined cathode performance towards hydrogen evolution reaction by tailoring material wettability, conductivity yielded by plasma treatment, and the catalyst loading. We discuss that nucleation of particles is facilitated by the appearance of carboxylic and hydroxyl groups triggered by oxygen plasma action. The best performance is associated with samples containing RuOx particles of 4–5 nm, which show hydrogen evolution onset potential to be about −5 mV (vs. RHE) in 0.5 M H2SO4 measured at a current density of −1 mA cm−2 and Tafel slope of 47.5 mV/dec. The material possesses stable performance at −10 mA cm−2 with a potential of about −160 mV.
The Weak 3D Topological Insulator Bi12Rh3Sn3I9
Authors: Lê Anh Mai , Kaiser Martin , Ghimire Madhav Prasad , Richter Manuel , Koepernik Klaus , Gruschwitz Markus , Tegenkamp Christoph , Doert Thomas , Ruck Michael
Published: June 2020

Topological insulators (TIs) gained high interest due to their protected electronic surface states that allow dissipation‐free electron and information transport. In consequence, TIs are recommended as materials for spintronics and quantum computing. Yet, the number of well‐characterized TIs is rather limited. To contribute to this field of research, we focused on new bismuth‐based subiodides and recently succeeded in synthesizing a new compound Bi12Rh3Sn3I9, which is structurally closely related to Bi14Rh3I9 – a stable, layered material. In fact, Bi14Rh3I9 is the first experimentally supported weak 3D TI. Both structures are composed of well‐defined intermetallic layers of ∞2[(Bi4Rh)3I]2+ with topologically protected electronic edge‐states. The fundamental difference between Bi14Rh3I9 and Bi12Rh3Sn3I9 lies in the composition and the arrangement of the anionic spacer. While the intermetallic 2D TI layers in Bi14Rh3I9 are isolated by ∞1[Bi2I8]2− chains, the isoelectronic substitution of bismuth(III) with tin(II) leads to ∞2[Sn3I8]2− layers as anionic spacers. First transport experiments support the 2D character of this material class and revealed metallic conductivity.
Palladium Complexes of Corroles and Sapphyrins
Authors: Chen Qiu‐Cheng , Fridman Natalia , Diskin‐Posner Yael , Gross Zeev
Published: June 2020

Palladium complexes of corrole and sapphyrin were prepared in high yield and fully characterized. The corrole provides a tetradentate/trianionic square planar coordination sphere for PdII, charge balanced by pyridinium. Both one and two PdII ions may be accommodated by the pentapyrrolic skeleton of the sapphyrin, and in each case the macrocycle acts as bidentate/monoanionic ligand and the inner‐sphere square planar geometry is completed by allyl anions coordinated in an η3 fashion. NMR spectroscopy and X‐ray crystallography data analyses uncovered the presence of interesting stereoisomers due to the flexibility of the ally ligands and also the pyrrole ring(s) that is/are not involved in metal binding.
Pericardial fat volume and coronary atherosclerotic markers among body mass index groups
Authors: Hassan Mohammed Bader , Nafakhi Hussein , Al‐Mosawi Abdulameer A.
Published: June 2020

Background

Increased pericardial fat volume (PFV) is associated with coronary atherosclerosis burden independent of body mass index (BMI) in many clinical studies. However, the association of PFV with markers of coronary atherosclerosis has not yet been assessed by dividing the patients according to BMI categories.

Hypothesis

To assess the association of PFV measured by multi‐detector CT (MDCT) angiography with coronary atherosclerotic markers (coronary artery calcium score [CAC], plaque type, and luminal stenosis) among BMI categories.

Methods

A total of 496 patients with suspected coronary artery disease who underwent 64‐slice MDCT angiography examination were enrolled. Patients divided into obese, overweight, and normal weight groups according to BMI degree.

Results

PFV showed a significant association with CAC, non‐calcified coronary plaque, and significant coronary stenosis in obese group. After adjusting for cardiac risk factors, the association of PFV with the non‐calcified coronary plaque and significant coronary stenosis persisted. There was a significant association between PFV with CAC and significant coronary stenosis in normal weight group. The association between PFV with CAC and significant coronary stenosis in normal weight was persisted afar adjusting for cardiac risk factors. No significant association was noted between PFV with coronary plaque type in normal weight group. There was no significant independent association between PFV with coronary atherosclerotic markers in overweight group.

Conclusions

Increased PFV was associated with advanced stage atherosclerosis in normal weight group, while increased PFV was associated with non‐calcified plaque in obese. These results highlight the differential relationship of PFV with coronary atherosclerotic markers among BMI categories.