bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional mesoporous poly (ionic liquid) derived from P123: From synthesis to catalysis and alkylation of styrene and o‐xylene
Authors: Wang Beibei , Sheng Xiaoli , Zhou Yuming , Zhu Zhiying , Liu Yonghui , Sha Xiao , Zhang Chao , Gao Huaying
Published: February 2019

A novel strategy was proposed for the fabrication of high‐performance acidic mesoporous poly ionic liquids catalyst. In this work, mesoporous poly ionic liquids (MPILs) were synthesized with P123 (PEO20PPO70PEO20) served as pore‐forming agent. Then, MPILs were treated with PW3− anion exchange, thereby fabricating PW/MPIL‐S(x). MPIL and PW/MPIL‐S(x) were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), Thermogravimetric analysis (TA), N2 adsorption–desorption and Fourier transform infrared (FT‐IR) spectra and X‐ray photoelectron spectroscopy (XPS) spectra. The effect of solvent and concentration of P123 on the morphology and mesoporous structure of MPILs were investigated systematically. And the results show that MPILs were featured with mesoporous channel structure, high surface area (up to 737 m2/g) and large pore volumes (1.16 cm3/g), which benefit heterogeneous phase reaction (such as, alkylation of styrene with o‐xylene). In the alkylation reaction, under optimal reaction conditions, the catalyst PW/MPIL‐THF (4.0 g) shows high conversion of styrene (100%) and PXE yield (96.21%), demonstrating the excellent catalytic activities. Furthermore, PW/MPIL‐S(x) are easy to be separated from the catalytic system by filtration and show no obvious decrease in catalytic activity after 6 cycle runs. The obtained PW/MPIL‐S(x) catalyst exhibit high thermal and mechanical stability as well, indicating extensive application in high temperature acidic catalysis. This work might open up a new method for the synthesizing of porous polymer catalysts in the future.
Thermodynamic and kinetic studies of crystal violet dye adsorption with poly(methyl methacrylate)–graphene oxide and poly(methyl methacrylate)–graphene oxide–zinc oxide nanocomposites
Authors: Rajabi Mostafa , Mahanpoor Kazem , Moradi Omid
Published: February 2019

We successfully prepared poly(methyl methacrylate) (PMMA)–graphene oxide (GO) and PMMA–GO–zinc oxide (ZnO) nanocomposites and characterized them using different techniques. The adsorption performances of the as‐prepared composites were investigated for crystal violet (CV) dye removal. The contact time as a main factor affecting the adsorption process by adsorbents was studied. Because the adsorption capacity value for CV was found to show no extensive changes after 35 min, 35 min was selected as the best contact time for our system. The adsorption results revealed that the best capacity of CV adsorption onto the PMMA–GO and PMMA–GO–ZnO nanocomposites occurred at pH 12 and 298 K. The respective entropies (−0.208 and −0.168 kJ mol−1 K−1) and enthalpies (−72.86 kJ/mol, and −55.54 kJ/mol) for PMMA–GO and PMMA–GO–ZnO and Gibbs energy revealed that the process of adsorption was exothermic. In addition, the Elovich, pseudo‐first‐order, intraparticle diffusion, and pseudo‐second‐order (four types) models were applied to our kinetic study. Our results indicate that CV adsorption onto PMMA–GO and PMMA–GO–ZnO was good with the pseudo‐second‐order (type 1) and pseudo‐first‐order models because of the low χ2 value and the high correlation coefficient value. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47495.
Do trainee teachers harm pupil attainment? Isolating the effect of pre‐service teachers on contemporaneous pupil performance in ‘high‐stakes’ tests
Authors: Greaves Ellen , Belfield Chris , Allen Rebecca
Published: February 2019

The prevalence of ‘pre‐service’ or ‘trainee’ teachers in schools is rising in England, driven by the expansion of school‐led routes to qualified teacher status and increasing demand for newly qualified teachers. This may have important implications for schools, which have historically been concerned with the impact of trainee teachers on their pupils’ attainment. There are, however, confounding factors which affect both the decision to host a trainee teacher and pupil attainment. We empirically model the impact of trainee teachers on contemporaneous pupil attainment in ‘high‐stakes’ exams, exploiting unique data combining national administrative data on pupil test scores with a survey of schools’ involvement with initial teacher training over multiple academic years. We use school fixed effects to account for time‐invariant school factors which may determine both schools’ teacher training decisions and pupil attainment. Counter to schools’ concerns, we find that pupil attainment in high‐stakes assessments, on average, is not significantly affected by the number of trainee teachers. This is an important empirical finding, as it suggests that the rapid expansion of school‐led teacher training is not likely to have a detrimental effect on pupil attainment in England, conditional on the set of schools that choose to engage with initial teacher training remaining similar: trainee teachers may still affect pupil attainment in schools that do not currently participate in initial teacher training, as these schools are typically more constrained.
Ultrasensitive chemiluminescence assay for cimetidine detection based on the synergistic improving effect of Au nanoclusters and graphene quantum dots
Authors: Yousefzadeh Ashraf , Abolhasani Jafar , Hassanzadeh Javad , Somi Mohammad Hossein
Published: February 2019

A novel and sensitive chemiluminescence (CL) procedure based on the synergetic catalytic effects of gold nanoclusters (Au NCs) and graphene quantum dots (GQDs) was developed for the reliable measurement of cimetidine (CM). The initial experiments showed that the KMnO4‐based oxidation of alkaline rhodamine B (RhoB) generated a very weak CL emission, which was intensively enhanced in the simultaneous presence of Au NCs and GQDs. CL intermediates can be adsorbed and gathered on the surface of Au NCs, becoming more stable. GQDs participate in the energy transferring processes and facilitate them. These improving effects were simultaneously obtained by adding both Au NCs and GQDs into the RhoB‐KMnO4 reaction. Consequently, the increasing effect of the Au NCs/GQDs mixture was more than that of pure Au NCs or GQDs, and a new nano‐assisted powerful CL system was achieved. Furthermore, a marked quenching in the emission of the introduced CL system was observed in the presence of CM, so the system was examined to design a sensitive sensor for CM. After optimization of influencing parameters, the linear lessening in CL emission intensity of KMnO4‐RhoB‐Au NCs/GQDs was verified for CM concentrations in the range 0.8–200 ng ml−1. The limit of detection (3Sb/m) was 0.3 ng ml−1. Despite being a simple CL method, good sensitivity was obtained for CM detection with reliable results for CM determination in human urine samples.
Spectroscopic characterization, calorimetric study and molecular docking to evaluate the bioconjugation of maltol with hemoglobin
Authors: Zhao Lining , Zhang Hao , Zhang Jing , Zong Wansong , Liu Rutao
Published: February 2019

Maltol, a food additive, is extensively used in our daily life. To date, its biological safety is still debated. In this article, binding interaction of maltol with bovine hemoglobin (BHb), an important functional protein, was studied by molecular docking research and spectroscopic and calorimetric measurements. We found that maltol could cause structural changes of BHb. By interacting with Glu 101 (1.27 Å) and Lys 104 (2.49 Å) residues, maltol changed the cavity structure and induced a microenvironment change around tryptophan (Trp) residue. Thermodynamic parameters obtained from isothermal titration calorimetry (ITC) measurement showed that hydrophobic forces were the main forces existing in this system. The association constant of K (8.0 ± 3.4 × 104 M−1) shows the mild ligand–protein binding for maltol with BHb. The α‐helix amount in BHb increased (59.6–62.6%) with different concentrations of maltol and the intrinsic fluorescence intensity was quenched by maltol, indicating the conformation changes and denaturation of BHb. This work presents the interactions of maltol with BHb at the molecular level and obtains evidence that maltol induces adverse effects to proteins in vitro.
Systematic review of fibrin glue in burn wound reconstruction
Authors: Miller R , Wormald J C R , Wade R G , Collins D P
Published: February 2019

Background

In the reconstruction of burns using split-skin grafts (SSGs), fibrin glue can be used to improve graft take and reduce haematoma formation, although the efficacy and cost-effectiveness are unknown. This systematic review evaluated outcomes of fibrin glue compared with conventional SSG attachment techniques. Outcomes of interest included SSG take, haematoma formation, patient satisfaction and cost-effectiveness.

Methods

This PROSPERO-registered review was performed in accordance with the Cochrane Handbook for Systematic Reviews of Interventions and PRISMA statement. Embase, PubMed, Cochrane and ClinicalTrial.gov databases were searched systematically. Observational and experimental studies comparing fibrin glue with other methods of SSG attachment in burn wounds were included. Risk of bias was assessed using the Cochrane risk-of-bias and Risk of Bias In Non-Randomized Studies – of Intervention tools. The quality of the evidence was assessed using the GRADE tool.

Results

Two RCTs and four observational studies were included. Graft take at day 5 was not significantly different between groups (3 studies, 183 individuals). Fibrin glue significantly reduced the risk of postoperative haematoma in two studies and reduced patient-reported pain in two studies, with suggested cost savings in four studies. All studies were at risk of methodological bias and the quality of the evidence was universally very low.

Conclusion

As the evidence is sparse, the quality very low and the risk of bias significant both within and across studies, it is not possible to make any recommendations regarding the use of fibrin glue in burn wounds.
Abdominal wall closure
Authors: de Beaux A C
Published: February 2019

Wound closure time is not coffee time
Randomized trial of oralversusenteral feeding for patients with postoperative pancreatic fistula after pancreatoduodenectomy
Authors: Wu J-M , Kuo T-C , Chen H-A , Wu C-H , Lai S-R , Yang C-Y , Hsu S-Y , Ho T-W , Liao W-C , Tien Y-W
Published: February 2019

Background

Whether continued oral feeding may have a negative impact on healing of postoperative pancreatic fistula (POPF) is unclear. The aim was to test the hypothesis that oral feeding is non-inferior to enteral feeding in closure of POPF after pancreatoduodenectomy, and to clarify the effects of oral feeding on the duration and grade of POPF.

Methods

This multicentre, non-inferiority randomized trial of oral or enteral feeding of patients with POPF after pancreatoduodenectomy recruited patients between August 2013 and September 2016. The primary efficacy outcome was the 30-day fistula closure rate. The prespecified non-inferiority margin was 15 per cent. Other efficacy outcomes included grade of fistula, and hospital stay and costs.

Results

A total of 114 patients were included, and received oral (57) or enteral (57) feeding. The two groups were balanced in baseline characteristics and no patient was lost to follow-up. In intention-to-treat analysis, oral feeding was non-inferior to enteral feeding in terms of 30-day fistula closure rate (88 versus 89 per cent respectively; difference –1·8 per cent, lower limit of 95 per cent c.i. –14·4 per cent; P = 0·020 for non-inferiority). Compared with enteral feeding, oral feeding significantly reduced hospital costs and duration of stay. No significant differences were noted in the number of patients whose POPF evolved into grade B/C, or other outcomes.

Conclusion

Oral feeding in patients with POPF after pancreatoduodenectomy did not increase the duration or grade of POPF, and was associated with reduced duration of stay and hospital costs. Registration number: NCT01755260 (http://www.clinicaltrials.gov).
Meta-analysis of negative pressure wound therapy of closed groin incisions in arterial surgery
Authors: Svensson-Björk R , Zarrouk M , Asciutto G , Hasselmann J , Acosta S
Published: February 2019

Background

Surgical-site infection (SSI) after groin incisions for arterial surgery is common and may lead to amputation or death. Incisional negative pressure wound therapy (NPWT) dressings have been suggested to reduce SSIs. The aim of this systematic review with meta-analysis was to assess the effects of incisional NPWT on the incidence of SSI in closed groin incisions after arterial surgery.

Methods

A study protocol for this systematic review of RCTs was published in Prospero (CRD42018090298) a priori, with predefined search, inclusion and exclusion criteria. The records generated by the systematic research were screened for relevance by title and abstract and in full text by two of the authors independently. The selected articles were rated for bias according to the Cochrane risk-of-bias tool.

Results

Among 1567 records generated by the search, seven RCTs were identified, including 1049 incisions. Meta-analysis showed a reduction in SSI with incisional NPWT (odds ratio (OR) 0·35, 95 per cent c.i. 0·24 to 0·50; P < 0·001). The heterogeneity between the included studies was low (I2 = 0 per cent). The quality of evidence was graded as moderate. Two studies had multiple domains in the Cochrane risk-of-bias tool rated as high risk of bias. A subgroup meta-analysis of three studies of lower limb revascularization procedures only (363 incisions) demonstrated a similar reduction in SSI (OR 0·37, 0·22 to 0·63; P < 0·001; I2 = 0 per cent).

Conclusion

Incisional NPWT after groin incisions for arterial surgery reduced the incidence of SSI compared with standard wound dressings. The risk of bias highlighted the need for a high-quality RCT with cost-effectiveness analysis.
Social Ecological Resilience and Mental Wellbeing of Irish Emigrant Survivors of Clerical Institutional Childhood Abuse
Authors: Moore Jeff , Flynn Marie , Morgan Mark
Published: February 2019

Survivors of clerical institutional childhood abuse (ICA) experience poor mental health outcomes in adulthood. Resilience research with this group has focused on psychological adjustment and we know less about the factors across the social ecology that support positive adaptation, including the impact of migration. This study explores the influence of resilience‐enhancing factors across the social ecology on the mental wellbeing (MWB) of Irish emigrant survivors of ICA and how this compares with non‐migrant survivors. Fifty‐six survivors based in the UK and 46 based in Ireland completed a quantitative survey that assessed resilience‐potentiating resources and associations with MWB. A further nine participants, resident in the UK, engaged in a structured interview which aimed to further explain these quantitative data. Results indicate more resilience‐enhancing resources across the ecology of emigrant survivors of ICA. Personal skills and competencies, such as problem‐focused coping, altruism and defiance, and social inclusion were associated with MWB regardless of country of residence. For the migrant group, social identity not defined by institutional care facilitated social inclusion. Migration to the UK and informal instrumental support in the aftermath of institutional care were identified as key turning points towards resilience.

Key Practitioner Messages

Multiple factors across the ecology influence the resilience of survivors of institutional childhood abuse (ICA).

Resilience strategies for survivors of ICA are contextual and may appear maladaptive to practitioners unfamiliar with the cultural context of this abuse.

For Irish emigrant survivors of ICA, problem‐focused coping, defiance, altruism, social inclusion, instrumental support and a social identity not defined by childhood abuse enhanced resilience.

Resilience is dynamic and emerges over time for adult survivors of chronic childhood abuse.

‘Explores the influence of resilience‐enhancing factors across the social ecology on the mental wellbeing… of Irish emigrant survivors of institutional childhood abuse’
Towards the Native Binding Modes of Antibiotics that Target Lipid II
Authors: Medeiros‐Silva João , Jekhmane Shehrazade , Breukink Eefjan , Weingarth Markus
Published: February 2019

The alarming rise of antimicrobial resistance (AMR) imposes severe burdens on healthcare systems and the economy worldwide, urgently calling for the development of new antibiotics. Antimicrobial peptides could be ideal templates for next‐generation antibiotics, due to their low propensity to cause resistance. An especially promising branch of antimicrobial peptides target lipid II, the precursor of the bacterial peptidoglycan network. To develop these peptides into clinically applicable compounds, detailed information on their pharmacologically relevant modes of action is of critical importance. Here we review the binding modes of a selection of peptides that target lipid II and highlight shortcomings in our molecular understanding that, at least partly, relate to the widespread use of artificial membrane mimics for structural studies of membrane‐active antibiotics. In particular, with the example of the antimicrobial peptide nisin, we showcase how the native cellular membrane environment can be critical for understanding of the physiologically relevant binding mode.
Efficacy and safety of bivalirudin during percutaneous coronary intervention in high‐bleeding‐risk elderly patients with chronic total occlusion: A prospective randomized controlled trial
Authors: Wang Yong , Zhao Hong‐Wei , Wang Cheng‐Fu , Fan Chun‐Yu , Zhang Xiao‐Jiao , Zhu Yu , Luo De‐Feng , Yu Guo‐Ning , Hou Ai‐Jie , Luan Bo
Published: February 2019

Objectives

To assess the efficacy and safety of bivalirudin during percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) in high‐bleeding‐risk elderly patients.

Background

Bivalirudin reduces PCI‐related bleeding; however, its efficacy and safety in patients with CTO, especially elderly patients with a high bleeding risk, remain unclear.

Methods

This single‐center prospective randomized controlled trial assigned 123 high‐bleeding‐risk elderly patients with CTO to either the unfractionated heparin (UFH) group (n = 55) or the bivalirudin group (n = 68). The primary efficacy endpoint was the incidence of major adverse cardiac events (MACEs) during hospitalization and at the 6‐month follow‐up. The safety endpoint was bleeding or procedure (access)‐related complications after PCI.

Results

MACE incidence was 17.6% and 20.0% in the bivalirudin and UFH groups, respectively (P = 0.82). Bleeding Academic Research Consortium (BARC) type 1–2 bleeding events during hospitalization were comparable between the groups (UFH: 10.9% vs. bivalirudin: 8.8%, P = 0.77). No BARC type 3–5 bleeding events or severe procedure (access)‐related complications (subcutaneous hematoma >5 cm) occurred in either group. At the 6‐month follow‐up, MACE incidence was comparable between the groups (UFH: 3.6% vs. bivalirudin: 1.5%, P = 0.59). The Kaplan–Meier analysis revealed that MACE‐free survival rates were comparable between the groups (P = 0.43). One case of BARC type 3–5 bleeding (fatal intracranial hemorrhage) was observed in the UFH group at the 6‐month follow‐up.

Conclusions

Bivalirudin and UFH showed comparable efficacy and safety in elderly patients with a high bleeding risk, undergoing PCI for CTO lesions.
Long‐term trends of treatment effect of stenting or bypass surgery in patients with ostial or shaft left main coronary artery disease
Authors: Yoon Yong‐Hoon , Lee Pil Hyung , Ahn Jung‐Min , Kang Do‐Yoon , Park Hanbit , Kwon Osung , Lee Kyusup , Lee Seung‐Whan , Park Duk‐Woo , Park Seung‐Jung ,   for the IRIS‐MAIN Registry Investigators
Published: February 2019

Background

Little is known about how the relative treatment effect of percutaneous coronary intervention (PCI) and coronary‐artery bypass grafting (CABG) on clinical outcomes in ostial or shaft left main coronary artery (LMCA) disease has evolved over time.

Methods

This study included 2,112 patients with ostial or shaft LMCA disease from IRIS‐MAIN registry who underwent PCI (n = 1,329) or CABG (n = 783). Patients were stratified by time period based on stent type availability: wave 1 (1995–2002, bare‐metal stent [BMS] era); wave 2 (2003–2006, first‐generation drug‐eluting stent [DES] era); and wave 3 (2007–2014, second‐generation DES era).

Results

Compared to CABG, PCI has been used more frequently from wave 1 to wave 3. PCI showed substantial improvements over time with respect to death (P for trend = 0.012); the composite of death, myocardial infarction (MI), or stroke (P for trend = 0.047); repeat revascularization (P for trend < 0.001); and major adverse cardiac and cerebrovascular events (MACCE; a composite of death, MI, stroke, or repeat revascularization) (P for trend < 0.001). By contrast, outcomes of CABG remained relatively stable over time. The gap between the treatment effects of CABG vs PCI for MACCE has narrowed over time; the adjusted hazard ratios for CABG compared to PCI during wave 1, 2, and 3 were 0.41 (95% confidence interval [CI]: 0.22–0.76), 0.47 (95% CI: 0.31–0.71), and 0.78 (95% CI: 0.50–1.20), respectively.

Conclusions

In patients with ostial or shaft LMCA disease, significant improvements in PCI outcomes resulted in a progressive decline in the gap between the outcomes of CABG and PCI.
Pulse‐steroid therapy in a 37‐year‐old man with acute motor and sensory axonal neuropathy: A case report
Authors: AlMohammedi Renad , AlJohani Samah , Bakheet Majid
Published: February 2019

Key Clinical Message

We report a case of 37‐year‐old man admitted with acute motor and sensory axonal neuropathy (AMSAN) which was treated with pulse‐steroid therapy after the plasmapheresis and intravascular immunoglobulin. The improvement of the symptoms of AMSAN after pulse‐steroid therapy may represent a therapeutic alternative for this variant of Guillain‐Barré syndrome.
Emphysematous cystitis in an elderly Japanese patient with type 2 diabetes mellitus
Authors: Yashima Hironori , Terasaki Michishige , Kushima Hideki , Hirano Tsutomu
Published: February 2019

Key Clinical Message

We report a rare but fatal case of emphysematous cystitis (EC) that presented as a typical image of gas bubbles within the urinary bladder wall on computed tomography (CT). This disease has a high mortality rate more than that reported previously based on recent literature review in Japan.
Sepsis after non‐perforated acute appendicitis
Authors: Faraji‐Goodarzi Mojgan
Published: February 2019

Key Clinical Message

Appendicitis is a worm‐like appendage whose base is located on the posterior side of the inner cecum. Acute appendicitis is uncommon in children younger than 5 years old. The patient was a 1.5‐year‐old boy who was admitted to the hospital with a primary complaint of fever, diarrhea, and vomiting. A pathological report of acute puffiness appendicitis with peri appendicitis was confirmed. After two weeks of treatment, the patient was discharged with an good general condition.
Endoanchors under 3D image fusion for a type IA endoleak after EVAR
Authors: Tinelli Giovanni , De Nigris Francesca , Minelli Fabrizio , Flore Roberto , Santoliquido Angelo , Tshomba Yamume
Published: February 2019

Key Clinical Message

The Heli‐FX technique for type IA EL under 3D‐IF proved to be accurate in terms of EL channel vision and correct endoanchors deployment. The EL volume rendering constant view allowed a precise anchors fixation at the EL channel. 3D‐IF confirmed to be a valid help in orientation and navigation during endovascular aortic procedure.
Zirconium‐Based Materials for Electrochemical Energy Storage
Authors: Wang Jianda , Xiao Xiao , Lu Yao , Wang Yuyin , Chen Changyun , Pang Huan
Published: February 2019

Zirconium‐based materials have emerged as momentous candidates for next‐generation batteries and supercapacitors, owing to their distinctive chemical and physical properties. For instance, garnet‐Li7La3Zr2O12 can be used as an electrolyte for solid‐state lithium‐ion batteries, which delivers high bulk lithium‐ion conductivities in the range of 4.0×10−4 S cm−1 at 20 °C. We provide a comprehensive review of up‐to‐date research progress in zirconium‐based materials. The most recent advances in the field of zirconium‐based electrodes, electrolytes, coatings, and separator materials for rechargeable batteries and supercapacitors are summarized. Moreover, the electrochemical performances in terms of the specific capacity, rate capability, and cycling stability of zirconium‐based materials are reported. Finally, we discuss the limitations and challenges of zirconium‐based energy storage materials, followed by their present status and prospects for future research. We believe that this Review will be helpful for researchers and scientists who are seeking promising materials for batteries and supercapacitors.
Cathodic Behaviour of Dicationic Imidazolium Bromides: The Role of the Spacer
Authors: Rocco Daniele , Chiarotto Isabella , D'Anna Francesca , Mattiello Leonardo , Pandolfi Fabiana , Rizzo Carla , Feroci Marta
Published: February 2019

The cathodic reduction of dicationic imidazolium bromides, whose spacer is either an aliphatic chain or a xylyl group, leads to the formation of the corresponding N‐heterocyclic carbenes (NHCs), which were isolated as the corresponding thiones, after reaction with elemental sulfur. The behaviour of the dications was compared with the corresponding monocations. The behaviour of dicarbenes depends on the nature of the spacer. This study evidenced that dicarbenes deriving from xylyl dications are less stable than the corresponding aliphatic ones (giving lower yields in thiones), due to a debenzylation reaction. On the other hand, the yields in thiones starting from aliphatic dications are higher than the corresponding monocations, suggesting a cooperative reduction at the electrode of the two imidazolium moieties. The cathodic process was confirmed using the co‐electrogenerated hydrogen to reduce 2,2,2‐trifluoroacetophenone to the corresponding alcohol.
Synthesis and Structures of Stable PtII and PtIV Alkylidenes: Evidence for π‐Bonding and Relativistic Stabilization
Authors: Lapierre Etienne A. , Piers Warren E. , Lin Jian‐Bin , Gendy Chris
Published: February 2019

Isolable cationic PtII and PtIV alkylidenes, proposed intermediates in catalytic organic transformations, are reported. The bonding in these species was probed by experimental, structural, spectroscopic, electrochemical and computational methods, providing direct evidence for π‐bonding, the often‐theorized relativistic stabilization of these species, and the influence of oxidation state.
True Blue Through Oxidation—A Thiaazulenic Heterophenoquinone as Electrochrome
Authors: Intorp Sebastian N. , Kushida Soh , Dmitrieva Evgenia , Popov Alexey A. , Rominger Frank , Freudenberg Jan , Hinkel Felix , Bunz Uwe H. F.
Published: February 2019

A thiaazulenic quinone TAQ was synthesized and its optical and redox properties were investigated. The deep blue‐colored compound is readily and reversibly reduced to the colorless anionic state. Electrochromic films were prepared and showed reversible switching behavior for the anodically coloring and NIR electrochromic material.
Wie viele Farben braucht eine Landkarte?
Authors: Kronenberg Alexander
Published: February 2019

Als Francis Guthrie 1852 die Karte von England einfärbte, benötigte er vier Farben, um sicherzustellen, dass Grafschaften mit gemeinsamer Grenzlinie nicht dieselbe Farbe bekamen. Er fragte sich, ob das für jede beliebige Landkarte, oder allgemeiner für jede Ebene, gelte.
Single drop breakup in turbulent flow
Authors: Komrakova Alexandra E.
Published: February 2019

The breakup process of a single drop in homogeneous isotropic turbulence was studied using direct numerical simulations. A diffuse interface free energy lattice Boltzmann method was applied. The detailed visualization of the breakup process confirmed breakup mechanisms previously outlined such as initial, independent, and cascade breakups. High‐resolution simulations allowed to visualize another drop breakup mechanism, burst breakup, which occurs when the mother drop has a large volume, and the flow is highly turbulent. The simulations indicate that the type of the breakup mechanism is a strong function of mother drop size and energy input. Large mother drops in highly turbulent flow fields are more likely to burst, producing a large number of drops of the size close to the Kolmogorov length scale. Small drops in moderate turbulence tend to break only once (initial breakup). The interfacial energy of a drop was tracked as a function of time during drop deformation and breakage. The maximum energy level of the deformed mother drop was compared to commonly used estimates of critical energy necessary to break a drop. Our results show that these reference levels of critical energy are usually underestimated. Moreover, in some cases even if the critical energy level was exceeded, the drop did not break because the time of the interaction between the drop and the eddies was not enough to finish the breakup. The numerical insight presented here can be used as a guideline for the selection of assumptions and simplifications behind breakup kernels.
Recent Advances on the Electrochemical Difunctionalization of Alkenes/Alkynes
Authors: Mei Haibo , Yin Zizhen , Liu Jiang , Sun Hailong , Han Jianlin
Published: February 2019

Electroorganic synthesis is an emerging area of high impact research in organic chemistry, which is considered as one of the green and efficient methods and attracts growing research attention. In this review, we summarized comprehensively the recent literature reports on the electrochemical oxidative difunctionalization of unsaturated C—C bonds. The reaction types described in this review included electrochemical intermolecular cyclization, electrochemical intramolecular cyclization, and electrochemical difunctionalization of alkenes/alkynes. This review focuses on the discussion of its synthetic generality for the preparation of functionalized compounds and the related electrochemical oxidative reaction mechanism.
Development of hair cell phenotype and calyx nerve terminals in the neonatal mouse utricle
Authors: Warchol Mark E. , Massoodnia Roxanna , Pujol Remy , Cox Brandon C. , Stone Jennifer S.
Published: February 2019

The vestibular organs of reptiles, birds, and mammals possess Type I and Type II sensory hair cells, which have distinct morphologies, physiology, and innervation. Little is known about how vestibular hair cells adopt a Type I or Type II identity or acquire proper innervation. One distinguishing marker is the transcription factor Sox2, which is expressed in all developing hair cells but persists only in Type II hair cells in maturity. We examined Sox2 expression and formation of afferent nerve terminals in mouse utricles between postnatal days 0 (P0) and P17. Between P3 and P14, many hair cells lost Sox2 immunoreactivity and the density of calyceal afferent nerve terminals (specific to Type I hair cells) increased in all regions of the utricle. At early time points, many calyces enclosed Sox2‐labeled hair cells, while some Sox2‐negative hair cells within the striola had not yet developed a calyx. These observations indicate that calyx maturation is not temporally correlated with loss of Sox2 expression in Type I hair cells. To determine which type(s) of hair cells are formed postnatally, we fate‐mapped neonatal supporting cells by injecting Plp‐CreER
T2:Rosa26
tdTomato mice with tamoxifen at P2 and P3. At P9, tdTomato‐positive hair cells were immature and not classifiable by type. At P30, tdTomato‐positive hair cells increased 1.8‐fold compared to P9, and 91% of tdTomato‐labeled hair cells were Type II. Our findings show that most neonatally‐derived hair cells become Type II, and many Type I hair cells (formed before P2) downregulate Sox2 and acquire calyces between P0 and P14.
The Influence of β‐Ammonium Substitution on the Reaction Kinetics of Aminooxy Condensations with Aldehydes and Ketones
Authors: Ogunwale Mumiye A. , Knipp Ralph J. , Evrard Clint N. , Thompson Lee M. , Nantz Michael H. , Fu Xiao‐An
Published: February 2019

The click‐chemistry capture of volatile aldehydes and ketones by ammonium aminooxy compounds has proven to be an efficient means of analyzing the carbonyl subset in complex mixtures, such as exhaled breath or environmental air. In this work, we examine the carbonyl condensation reaction kinetics of three aminooxy compounds with varying β‐ammonium ion substitution using Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS). We determined the activation energies for the reactions of the aminooxy compounds ATM, ADMH and AMAH with a panel of ketones and aldehydes that included acrolein and crotonaldehyde. The measurements indicate that the activation energies for the oximation reactions are quite low, less than 75 kJ mol−1. ADMH is observed to react the fastest with the carbonyls studied. We postulate this result may be attributed to the ADMH ammonium proton effecting a Brønsted‐Lowry acid‐catalyzed elimination of water during the rate‐determining step of oxime ether formation. A theoretical study of oxime ether formation is presented to explain the enhanced reactivity of ADMH relative to the tetraalkylammonium analog ATM.
Double‐Exchange Magnetic Interactions in High‐Temperature Ferromagnetic Iron Chalcogenide Monolayers
Authors: Kumar Sourabh , Mondal Chiranjit , Pathak Biswarup
Published: February 2019

Smythite (
) is an iron‐based chalcogenide with a lamellar structure, different from the compositionally identical mineral greigite. Owing to their natural abundance, such transition metal chalcogenides are promising materials for low‐cost spintronic‐based devices. Herein, we discuss the charge transfer processes and complex magnetic ordering in a two‐dimensional (2D) smythite lattice. We find that
redox couple and complex magnetic ordering are governing factors in the charge transfer processes. A very strong ferromagnetic in‐lattice coupling is also observed, which is attributed to the presence of three Fe‐centres. To describe the magnetic behaviour molecular and periodic approaches have been considered. We found a substantial increase in Curie temperature with applied mechanical stress due to opening of the double exchange interaction angle. We also observe an in‐plane Jahn−Teller distortion, which is further confirmed by the spin−orbit counter plot. Our study thus provides an insight into the double exchange mechanism favoured by the
redox couple and results in a strong ferromagnetic ordering.
The Effect of the Phospholipid Bilayer Environment on Cholesterol Crystal Polymorphism
Authors: Varsano Neta , Beghi Fabio , Dadosh Tali , Elad Nadav , Pereiro Eva , Haran Gilad , Leiserowitz Leslie , Addadi Lia
Published: February 2019

Cholesterol crystallization from mixtures of unesterified cholesterol with phospholipids and cholesterol esters is believed to be a key event in atherosclerosis progression. Not much is understood, however, about the influence of the lipid environment on cholesterol crystallization. Here we study cholesterol monohydrate crystal formation from mixed bilayers with palmitoyl‐oleoyl‐phosphatidylcholine (POPC), dipalmitoyl‐phosphatidylcholine (DPPC) and sphingomyelin. We show that disordered phospholipids and sphingomyelin stabilize the formation of crystal plates of the triclinic cholesterol monohydrate polymorph, whereas saturated glycerolipids stabilize helical and tubular crystals of the metastable monoclinic polymorph. We followed the subsequent transformation of these helical crystals into the stable triclinic plates. Discovering the relations between membrane lipid composition and cholesterol crystal polymorphism may provide important clues to the understanding of cholesterol crystal formation in atherosclerosis.
6‐Phenylpyrrolocytidine: An Intrinsically Fluorescent, Environmentally Responsive Nucleoside Analogue
Authors: Cho Sung Ju , Ghorbani‐Choghamarani Arash , Saito Yoshio , Hudson Robert H.E.
Published: February 2019

The detailed synthetic protocols for the preparation of phosphoramidite reagents compatible with standard, automated oligonucleotide synthesis for the 2′‐deoxy‐ and ribo‐6‐phenylpyrrolocyitidine are reported. Each protocol starts with the parent nucleoside and prepares the 5′‐O‐dimethoxytrityl‐N4‐benzoyl‐5‐iodocytosine derivative for the nucleobase modification chemistry. The key step is the direct formation of 6‐phenylpyrrolocytosine aglycon via a sequential, one‐pot Pd‐catalyzed Sonogashira‐type cross‐ coupling followed by a 5‐endo‐dig cyclization. Subsequent standard transformations provide the deoxy‐ and 2′‐O‐tert‐butyldimethysilyl protected ribo‐ nucleoside phosphoramidite reagents. © 2019 by John Wiley & Sons, Inc.
SRL Communi(ty)cate
Authors: Tárnok Attila
Published: February 2019

See article on pages 141–143 in this issue
An enhanced anonymous and unlinkable user authentication and key agreement protocol for TMIS by utilization of ECC
Authors: Ostad‐Sharif Arezou , Abbasinezhad‐Mood Dariush , Nikooghadam Morteza
Published: February 2019

The telecare medicine information systems (TMISs) not only help patients to receive incessant health care services but also assist the medical staffs to access patients' electronic health records anytime and from anywhere via Internet. Since the online communications are exposed to numerous security threats, the mutual authentication and key agreement between patients and the medical servers are of prime significance. During the recent years, various user authentication schemes have been suggested for the TMISs. Nonetheless, most of them are susceptible to some known attacks or have high computational cost. Newly, an effective remote user authentication and session key agreement protocol has been introduced by Ravanbakhsh and Nazari for health care systems. Besides the nice contributions of their work, we found that it has two security weaknesses, namely, known session‐specific temporary information attack and lack of perfect forward secrecy. As a result, to overcome these deficiencies, this paper suggests a novel anonymous and unlinkable user authentication and key agreement scheme for TMISs using the elliptic curve cryptosystem (ECC). We have evaluated the security of the proposed scheme by applying the automated validation of internet security protocols and applications (AVISPA) tool with the intention of indicating that our scheme can satisfy the vital security features. In addition, we have compared the proposed protocol with related schemes to show that it has a proper level of performance. The obtained results demonstrate that the new scheme is more preferable considering both efficiency and security criteria.
Spinal Cord Regeneration in Amphibians: A Historical Perspective
Authors: Freitas Polina D. , Yandulskaya Anastasia S. , Monaghan James R.
Published: February 2019

In some vertebrates, a grave injury to the central nervous system (CNS) results in functional restoration, rather than in permanent incapacitation. Understanding how these animals mount a regenerative response by activating resident CNS stem cell populations is of critical importance in regenerative biology. Amphibians are of a particular interest in the field because the regenerative ability is present throughout life in urodele species, but in anuran species it is lost during development. Studying amphibians, who transition from a regenerative to a nonregenerative state, could give insight into the loss of ability to recover from CNS damage in mammals. Here, we highlight the current knowledge of spinal cord regeneration across vertebrates and identify commonalities and differences in spinal cord regeneration between amphibians.
Long‐term sound and movement recording tags to study natural behavior and reaction to ship noise of seals
Authors: Mikkelsen Lonnie , Johnson Mark , Wisniewska Danuta Maria , van Neer Abbo , Siebert Ursula , Madsen Peter Teglberg , Teilmann Jonas
Published: February 2019

The impact of anthropogenic noise on marine fauna is of increasing conservation concern with vessel noise being one of the major contributors. Animals that rely on shallow coastal habitats may be especially vulnerable to this form of pollution.

Very limited information is available on how much noise from ship traffic individual animals experience, and how they may react to it due to a lack of suitable methods. To address this, we developed long‐duration audio and 3D‐movement tags (DTAGs) and deployed them on three harbor seals and two gray seals in the North Sea during 2015–2016.

These tags recorded sound, accelerometry, magnetometry, and pressure continuously for up to 21 days. GPS positions were also sampled for one seal continuously throughout the recording period. A separate tag, combining a camera and an accelerometer logger, was deployed on two harbor seals to visualize specific behaviors that helped interpret accelerometer signals in the DTAG data.

Combining data from depth, accelerometer, and audio sensors, we found that animals spent 6.6%–42.3% of the time hauled out (either on land or partly submerged), and 5.3%–12.4% of their at‐sea time resting at the sea bottom, while the remaining time was used for traveling, resting at surface, and foraging. Animals were exposed to audible vessel noise 2.2%–20.5% of their time when in water, and we demonstrate that interruption of functional behaviors (e.g., resting) in some cases coincides with high‐level vessel noise. Two‐thirds of the ship noise events were traceable by the AIS vessel tracking system, while one‐third comprised vessels without AIS.

This preliminary study demonstrates how concomitant long‐term continuous broadband on‐animal sound and movement recordings may be an important tool in future quantification of disturbance effects of anthropogenic activities at sea and assessment of long‐term population impacts on pinnipeds.
Development of optimization model for power system operation, outline of model design and verification of output
Authors: Honda Atsuo , Tezuka Koichiro , Okamura Tomohito , Kawamoto Kaoru , Shimizu Shoji , Harada Kohei , Tanabe Takahito , Shirakawa Tatsuya , Takahashi Tomohiro
Published: February 2019

Osaka Gas Co., Ltd., jointly with NTT DATA Mathematical Systems Inc., has developed unit‐commitment model for optimizing dispatch of power generation units. Main purpose of this development is to simulate the future world of electric power system in accordance with national energy policy aiming to introduce large amount of renewable energy as well as vitalized cross‐border power exchange via PX market to enhance economically‐efficient power system operation. The model incorporates not only constraints of supply‐demand balance but also constraints of operating reserves, regulation reserves, maximum CO2‐emissions, etc.
MWCNT‐modified Electrode for Voltammetric Determination of Allura Red and Brilliant Blue FCF in Isotonic Sport Drinks
Authors: Sierra‐Rosales Paulina , Toledo‐Neira Carla , Ortúzar‐Salazar Pía , Squella Juan Arturo
Published: February 2019

A fast and simple electrochemical sensor is presented for the determination of allura red and brilliant blue in isotonic sport drinks, using a glassy carbon electrode modified with multi‐walled carbon nanotubes. The electrochemical behavior of the colorants was studied by cyclic and differential pulse voltammetry in 0.1 M PBS, pH 7.0. The solution pH, the amount of nanomaterial on the surface of the electrode and the accumulation time of each colorant were optimized. Under the optimal conditions, the sensor exhibited a linear response to allura red and brilliant blue with detection limits of 7 μg L−1 and 52 μg L−1, respectively. The sensor was applied to the analysis of commercial isotonic sports drinks that contain individual or mixed colorants, showing good sensitivity and reproducibility. The results were compared with a chromatographic method showing that the levels of colorants are low and did not show a risk for a consumer's health.
Electrochemical Sensor Based on Multi‐walled Carbon Nanotubes and Cobalt Phthalocyanine Composite for Pyridoxine Determination
Authors: Porto Laís Sales , da Silva Daniela Nunes , Silva Maria Cristina , Pereira Arnaldo César
Published: February 2019

In this work, an electrochemical sensor based on pyrolytic graphite electrode (PGE), cobalt phthalocyanine (CoPc) and multiwalled carbon nanotube (MWCNT) composite designed as PGE‐MWCNT/CoPc was developed and validated for pyridoxine (vitamin B6) determination employing Differential Pulse Voltammetry (DPV). The electrochemical behaviour of pyridoxine at the PGE‐MWCNT/CoPc has been evaluated and the charge transfer coefficient, α, and the charge transfer rate constant, κ, were calculated as 0.30 and 11.67±0.43 s−1, respectively, which indicates that, although this system is irreversible, it is viable kinetically to be used as a sensor. The optimized experimental conditions were pH 5.5 in 0.30 mol L−1 phosphate buffer. The linear range found was 10 to 400 μmol L−1 of pyridoxine, with r=0.9987. The limits of detection and quantification were 0.50 and 1.67 μmol L−1, respectively, showing the good sensitivity of the method. The method was successfully applied for the pyridoxine determination in real samples of pharmaceutical formulation with RSD% lower than 5 % indicating that it can be used for routine quality control pharmaceutical formulations containing pyridoxine. Furthermore, it has the advantages of a fast response, a low detection limit and low cost.
A Novel Electrochemical Sensor Based on Silsesquioxane/Nickel (II) Phthalocyanine for the Determination of Sulfanilamide in Clinical and Drug Samples
Authors: Vanoni Caio Raphael , Winiarski João Paulo , Nagurniak Glaucio Régis , Magosso Hérica Aparecida , Jost Cristiane Luisa
Published: February 2019

This paper describes the immobilization of nickel (II) phthalocyanine‐tetrasulfonic acid tetrasodium salt (NiTsPc) in 3‐n‐propyl(3‐methylpyridinium) silsesquioxane chloride (Si3Pic+Cl−). This hybrid material was synthetized and characterized by 29Si NMR CP‐MAS, FTIR and DRS. The modified material, designated as Si3Pic+Cl−/NiTsPc, was used to build carbon paste electrodes to determine sulfanilamide (SFL) by differential pulse voltammetry. The modified electrode showed a higher current response when compared to the bare carbon paste electrode. The evaluation of SFL was possible in the presence of salicylic acid, commonly used in solid ointment compositions in a high concentration. Theoretical calculations using density functional theory were done aiming to shed light at dimerization process at SFL. The oxidation peak increased with increasing concentrations of SFL in the range of 35–301 μmol L−1. The LOD and LOQ values obtained were 12 and 35 μmol L−1 of SFL, respectively. The novel electrochemical sensor was successfully applied for the determination of SFL in pet drug samples, urine and serum through the standard addition method. Validation was performed through a comparison with values obtained by the molecular absorption spectrometry method and there were no significant differences in the results, as confirmed by the statistical paired t‐test. This demonstrates the promise of a new approach for analytical application in clinical and drug samples of sulfonamide compounds.