bluuebunny/crossref_metadata_2025 huggingface dataset:
Regional practice norms for the care of childhood cancer survivors at risk for cardiomyopathy: A Delphi study
Authors: Kenney Lisa B. , Ames Bethany , Margossian Renee , Moss Kerry , Michaud Alexis L. , Williams David N. , Nohria Anju
Published: May 2019

Background

Treatment‐associated cardiomyopathy is a leading cause of morbidity and mortality for childhood cancer survivors (CCS). As evidence is not available to guide the management of CCS at risk for cardiomyopathy, we aim to describe the collective opinion of regional experts for the care of these patients using a consensus‐based Delphi methodology.

Procedure

Nineteen physicians from the New England region who care for CCS treated with cardiotoxic therapy (anthracyclines, thoracic radiation) participated in a Delphi panel querying their management approach, using three rounds of anonymous questionnaires formatted as five clinical scenarios. Consensus ≥ 89% agreement.

Results

The response rate was 100% for the first round and 95% for subsequent rounds. Panelists reached consensus on screening asymptomatic CCS with serial echocardiograms (94%) and electrocardiograms (89%), with some disagreement on frequency during pregnancy (83%). All panelists agreed with exercise promotion, with no restrictions on weight training. Consensus was reached on indications for referrals; cardiology for asymptomatic left ventricular dysfunction (ALVD) (100%) and maternal–fetal medicine for pregnancy (94%). In the scenario of ALVD, there was disagreement on the benefit of additional cardiac testing (50% cardiologists recommended cardiac MRI), and although all panelists endorsed treating with angiotension‐converting enzyme (ACE) inhibitors, most adult cardiologists (75%) also recommended therapy with beta blockers, compared with none of the pediatric cardiologists or primary‐care physicians.

Conclusions

Despite a lack of evidence to guide the management of CCS at risk for cardiomyopathy, a panel of regional physicians reached consensus on managing most clinical scenarios. A controversial area requiring further study is the medical management of ALVD.
Selective dispersion of silver nanowires in epoxy/polyetherimide binary composites with enhanced electrical conductivity: a study of curing kinetics and morphology
Authors: Liu Yuanyuan , Yang Xiaodan , Yue Lansong , Li Weizhen , Gan Wenjun , Chen Kaimin
Published: May 2019

This study reports on the preparation and characterization of epoxy/polyetherimide (EP/PEI) binary system containing low content of silver nanowires (AgNWs). The system was designed to form a co‐continuous structure during reaction‐induced phase separation of EP/PEI blend. With selective distribution of the AgNWs in continuous EP‐rich phase, a low percolation threshold at 3 wt% content of AgNWs was obtained in EP/PEI composite. The glass transition temperature, electrical conductivity, and thermal conductivity were all enhanced by the addition of low content of AgNWs. The surface resistivity of the EP/PEI blend decreased from 6.5 × 1016 Ω to 9.6 × 105 Ω with the addition of 3.0 wt% AgNWs, and meanwhile thermal conductivity was improved by 38.2%. Furthermore, AgNWs showed a critical impact on the kinetics of reaction‐induced phase separation and the formation of co‐continuous network structure. The process of phase separation of the thermosetting/thermoplastic blends was characterized by optical microscopy, time‐resolved light scattering, differential scanning calorimetry, and scanning electron microscopy.
Barriers towards effective pharmacovigilance systems of biosimilars in rheumatology: A Latin American survey
Authors: Castañeda‐Hernández Gilberto , Sandoval Hugo , Coindreau Javier , Rodriguez‐Davison Luis Felipe , Pineda Carlos
Published: May 2019

Purpose

This review summarises the current status of regulatory guidelines for the approval of biosimilars in Latin America and highlights the main barriers to effective pharmacovigilance in this region. We also report results from a survey of Latin American rheumatologists assessing their understanding of prescribing biosimilars and the pharmacovigilance of these drugs.

Methods

We reviewed the current guidelines for the regulatory approval of biosimilars and barriers to effective pharmacovigilance in Latin American countries. Rheumatologists attending the II Pan‐American League of Rheumatology Associations PANLAR Review Course (Biosimilars update) in Lima, Peru were asked to complete a short survey to determine their knowledge of biosimilars.

Results

Many Latin American countries continue to lag behind Europe and the United States in establishing regulatory guidance and effective pharmacovigilance systems for biosimilars. Results from our survey also highlight a lack of awareness regarding the availability of biosimilars, their nomenclature, automatic substitution, and reporting adverse drug reactions because of these drugs.

Conclusions

The main barriers to effective pharmacovigilance in Latin America are the lack of consensus on the interchangeability of reference biologics and biosimilars, and the need for more suitably trained personnel to carry out effective postmarketing pharmacovigilance of biosimilars. Inconsistencies in biosimilar nomenclature make it difficult to adequately trace drugs and record adverse drug reactions associated with their use, creating a barrier to the global pharmacovigilance of biologics.
Construction of anion‐responsive crosslinked polypseudorotaxane based on molecular recognition of pillar[5]arene
Authors: Boominathan Muniyappan , Kiruthika Jeyavelraman , Arunachalam Murugan
Published: May 2019

A pillar[5]arene pendant polymer (Poly‐P[5]A) is synthesized via ROMP using Grubb's first‐generation catalyst. GPC analysis of the polymer suggested ~30 pendant pillar[5]arene units in the polymer. Supramolecular polypseudorotaxane assembly is constructed by intermolecularly crosslinking pendant pillar[5]arene units using a bispyridinium guest via host–guest complexation. Formation of the polypseudorotaxane assembly is characterized by 1D/2D NMR techniques and DLS analysis. Moreover, anion‐responsiveness of the polypseudorotaxane assembly is demonstrated by 1H NMR spectroscopic analysis using chloride anion as external stimulus. Scanning electron microscopic analysis of the poly‐P[5]A showed breath‐figure assembly and upon crosslinking with G.2PF6 the polymer self‐assemble to give a supramolecular polymer network. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1508–1515
Tumor‐Targeting W18O49 Nanoparticles for Dual‐Modality Imaging and Guided Heat‐Shock‐Response‐Inhibited Photothermal Therapy in Gastric Cancer
Authors: Yang Zhengyang , Wang Jiafeng , Liu Song , Sun Feng , Miao Ji , Xu En , Tao Liang , Wang Yuxin , Ai Shichao , Guan Wenxian
Published: May 2019

Photothermal therapy (PTT) is an emerging noninvasive and precise localized therapeutic modality; however, it is deeply limited by its poor tumor accumulation, inadequate photothermal conversion efficiency, and the thermoresistance of cancer cells. Aimed at these shortcomings, tumor‐targeting nanoparticles (iRGD‐W18O49‐17AAG) comprising carboxyl‐group‐functionalized W18O49 nanoparticles, integrin‐targeting peptide iRGD, and HSP90‐inhibitor 17AAG are developed. The W18O49 nanoparticles act as excellent PTT carriers and computed tomography (CT) imaging contrast agents. The ring type polypeptide iRGD promotes the accumulation of nanoparticles in the tumour and further penetration into cancer cells. The introduction of 17AAG can inhibit the heat‐shock response and overcome the thermoresistance, thus increasing the curative effect of PTT and reducing the chance of tumor recurrence. The W18O49 nanoparticles can also be used to monitor and guide the phototherapeutic through CT and near‐infrared fluorescence imaging after modification with Cy5.5. In addition, superior biosafety is also indicated in both preliminary in vitro and in vivo assessments. The potential of iRGD‐W18O49‐17AAG in tumor targeting, dual modality imaging‐guided and remarkable enhanced PTT of gastric cancer with ignorable side effect both in vitro and in vivo, which may be further applied in clinic, is highlighted.
Exploring the overlapping binding sites of ifenprodil and EVT‐101 in GluN2B‐containing NMDA receptors using novel chicken embryo forebrain cultures and molecular modeling
Authors: Fjelldal Marthe F. , Freyd Thibaud , Evenseth Linn M. , Sylte Ingebrigt , Ring Avi , Paulsen Ragnhild E.
Published: May 2019

N‐methyl‐d‐aspartate receptors (NMDAR) are widely expressed in the brain. GluN2B subunit‐containing NMDARs has recently attracted significant attention as potential pharmacological targets, with emphasis on the functional properties of allosteric antagonists. We used primary cultures from chicken embryo forebrain (E10), expressing native GluN2B‐containing NMDA receptors as a novel model system. Comparing the inhibition of calcium influx by well‐known GluN2B subunit‐specific allosteric antagonists, the following rank order of potency was found: EVT‐101 (EC50 22 ± 8 nmol/L) > Ro 25‐6981 (EC50 60 ± 30 nmol/L) > ifenprodil (EC50 100 ± 40 nmol/L) > eliprodil (EC50 1300 ± 700 nmol/L), similar to previous observations in rat cortical cultures and cell lines overexpressing chimeric receptors. The less explored Ro 04‐5595 had an EC50 of 186 ± 32 nmol/L. Venturing to explain the differences in potency, binding properties were further studied by in silico docking and molecular dynamics simulations using x‐ray crystal structures of GluN1/GluN2B amino terminal domain. We found that Ro 04‐5595 was predicted to bind the recently discovered EVT‐101 binding site, not the ifenprodil‐binding site. The EVT‐101 binding pocket appears to accommodate more structurally different ligands than the ifenprodil‐binding site, and contains residues essential in ligand interactions necessary for calcium influx inhibition. For the ifenprodil site, the less effective antagonist (eliprodil) fails to interact with key residues, while in the EVT‐101 pocket, difference in potency might be explained by differences in ligand‐receptor interaction patterns.
Detoxification enzymes associated with butene‐fipronil resistance in Epacromius coerulipes
Authors: Jin Yongling , Gao Yugang , Zhang Haiyan , Wang Liyan , Yang Kejun , Dong Hui
Published: May 2019

BACKGROUND

Epacromius coerulipes is a widely distributed locust pest species. Chemical control is the main method used to kill locusts; however, this can result in the selection of locusts with resistance to chemical pesticides. Therefore, the study of resistance is of great significance for the sustainable management of locusts.

RESULTS

In this study, to investigate the relationship between detoxification enzymes and butene‐fipronil resistance in E. coerulipes, resistant strains of the locust were compared with sensitive strains. The synergism of synergistic agents was significantly enhanced, and the activities of multifunctional oxidase, carboxylesterase, and glutathione sulfur transferase were significantly increased. Transcriptome sequencing revealed 226 detoxification enzyme genes and 23 upregulated genes. Neighbor‐joining was used to construct a phylogenetic tree of related gene families, which included 59 P450 genes, 52 carboxylesterases (CarE) genes, and 25 glutathione S‐transferase (GST) genes. Reverse transcription polymerase chain reaction (RT‐PCR) analysis results of overexpressed genes in the resistant population combined with a phylogenetic tree showed that four P450 genes belonged to the CYP6, CYP4, CYP18 and CYP302 families, two CarE genes belonged to Clade A families, and one GST gene belonged to the Sigma family. These family members were annotated as detoxification enzyme genes of metabolic insecticide in the transcriptome databases.

CONCLUSIONS

This study showed that P450, CarE and GST together resulted in moderate resistance to butene‐fipronil in locusts. The analysis revealed several overexpressed detoxification enzyme genes that will be the focus of future studies on the mechanism of resistance to butene‐fipronil. © 2019 Society of Chemical Industry
Protein elicitor PeaT1 enhanced resistance against aphid (Sitobion avenae) in wheat
Authors: Li Lin , Wang Shuangchao , Yang Xiufen , Francis Frederic , Qiu Dewen
Published: May 2019

BACKGROUND

Sitobion avenae, a dominant aphid in wheat that causes huge annual losses in agriculture, is mainly controlled using chemical pesticides. In this study, we investigated a protein elicitor, PeaT, for its induction of the defense response in wheat against Sitobion avenae.

RESULTS

Intrinsic rates of increase in second and third generations of S. avenae decreased in the PeaT1 (second generation 0.28 ± 0.03, third generation 0.26 ± 0.01) treatment compared with controls (second generation 0.31 ± 0.01, third generation 0.28 ± 0.01). S. avenae preferred to colonize control rather than PeaT1‐treated wheat seedlings in a host selection test. PeaT1‐treated wheat leaves possessed more trichomes and wax that formed a disadvantageous surface environment for S. avenae. Both salicylic acid (SA) and jasmonic acid (JA) accumulated significantly in PeaT1‐treated wheat seedlings.

CONCLUSION

These results showed that PeaT1 modified physical surface structures in wheat to reduce reproduction and deter colonization by S. avenae. SA and JA were involved in the induced physical defense process. This study provided evidence for use of PeaT1 as a ‘vaccine’ to protect wheat from Sitobion avenae. © 2019 Society of Chemical Industry
Structural Properties and Wettability of TiO2 Nanorods
Authors: Shukla Gaurav , Kumar Chandan , Angappane Subramanian
Published: May 2019

The structural and wetting properties of as‐deposited, annealed, and UV‐exposed TiO2‐slanted nanorods grown on different substrates have been studied. The slanted nanorods of 250 nm thickness are deposited on silicon, fluorine‐doped tin oxide, and glass at 80° using glancing angle deposition (GLAD) by employing e‐beam evaporation. The structural evolution shows that the prior seeding on the substrate affects the morphology dramatically, while a different angle of deposition can tune a plane substrate for exciting morphologies by GLAD technique. Annealing and UV exposure redefine the grown material and change the structural and wetting behavior of the TiO2 films. Notably, annealing the sample at 500 °C for 1 h has decreased the contact angle, and all the annealed samples become hydrophilic. Further, the UV radiation exposure makes all the samples super‐hydrophilic. It is demonstrated that by choosing an appropriate substrate, controlled properties of our interest with or without external stimuli can be achieved. Nevertheless, these samples will find interesting applications in self‐cleaning, photocatalysis, gas sensing, antireflection coating, etc.
Super‐Superexchange Influence on Magnetic Ordering in Ni3B2O6 Kotoite
Authors: Sofronova Svetlana N. , Nazarenko Ilya I.
Published: May 2019

Using ab initio software package WIEN2k, the calculations of electronic propertiesand of the energies of various magnetically ordered structures are carried out and possible mechanisms of magnetic ordering are analyzed in Ni3B2O6. The superexchange (Ni‐O‐Ni) and super‐superexchange interactions (Ni‐O‐B‐O‐Ni) are calculated, a magnetic ordering model is proposed.
A First Principle Study of Structural, Electronic, and Vibrational Properties of LuPdBi Half‐Heusler Alloy
Authors: Gupta Yuhit , Sinha Murari Mohan , Verma Suram Singh
Published: May 2019

Half‐Heusler alloys offer a variety of applications in the field of electronics and superconductors. They are suitable for the formation of thermoelectric materials and superconductors. Their stupendous applications arouse curiosity among many researchers. Therefore, in this paper, a systematic study of structural, electronic, and vibrational properties has been done using density functional theory and density functional perturbation theory. The structural properties such as lattice constant, bulk modulus, and pressure derivative of bulk modulus have been calculated. Electronic and bonding properties have been examined from electronic band structure, charge density contours, and Fermi surfaces. The phonon dispersion spectra and phonon density of states for LuPdBi are reported and discussed for the first time. Moreover, the eigenvector displacements for optical phonons at the zone center are also described to support the reliability of phonon calculations. The computation of phonon spectra disclosed the fact that the resulted phonons are real. Real frequencies of phonons are witness of alloy stability in the cubic phase. The superconducting properties have also been evaluated by employing electron–phonon interaction and Eliashberg theory. The Coulomb pseudopotential variable µ* is selected to be 0.11 and the computed value of transition temperature is found to be Tc = 1.802 K. This value of Tc is in agreement with the experimental value of Tc = 1.80 K.
Differentiation of 2‐hydroxyglutarate enantiomers and its lactones by gas chromatography/electron ionization tandem mass spectrometry
Authors: Strain Shinji K. , Groves Morris D. , Emmett Mark R.
Published: May 2019

Rationale

2‐Hydroxyglutarate (2‐hg) exists as enantiomers and can readily undergo cyclization to its lactone. Gas chromatography/electron ionization mass spectrometry (GC/EI‐MS) has been used to separate 2‐hg enantiomers in bodily fluids but the assay cannot simultaneously measure cyclic and acylic 2‐hg enantiomers. Furthermore, the assignment of ion structures was not verified by complementary MS data.

Methods

GC/EI‐MS and product ion analysis were used to obtain MS and MS/MS spectra of 2‐hg, deuterated and 13C‐labeled 2‐hg, and 2‐hg lactone. Ion structures and EI fragmentation mechanisms were determined by fragmentation pattern and isotopologue comparisons. Using the EI data, a GC/MS/MS assay was developed to separate and detect 2‐hg enantiomers and 2‐hg lactone enantiomers in blood and urine using a cyclodextrin capillary column.

Results

A new ion structure was predicted for the 85 m/z fragment than what was previously hypothesized, and the 117 m/z ion was the only fragment unique to the linear 2‐hg compound. MS/MS data suggested that the majority of the fragments were the result of secondary fragmentation. Finally, separation of serum and urine 2‐hg and 2‐hg lactone enantiomers was achieved, and the acyclic 2‐hg compound was found to be the major compound detected, though the amount of lactone detected was considerable in a number of samples.

Conclusions

Unique EI fragmentation pathways for both 2‐hg and the 2‐hg lactone have been described. Subsequently, the GC/MS/MS assay presented herein has significant potential as a novel clinical assay as it separates and detects both 2‐hg enantiomers and the 2‐hg lactone enantiomers, a capability which has not been previously demonstrated by any other assay to date.
Study of the impurity profile and polymerized impurity in mezlocillin sodium by multiple heart‐cutting two‐dimensional liquid chromatography coupled with ion trap time‐of‐flight mass spectrometry
Authors: Wang Jian , Zhou Jinjin , Xu Yu , Zhu Bingqi , Li Huiyi
Published: May 2019

Rationale

Eleven impurities and one polymerized impurity in mezlocillin were identified and their formation mechanisms were investigated in this study. The sources and reasons for the formation of impurities were revealed, which may guide industry to improve the manufacturing process and storage conditions and reduce the content of impurities in products. The results from this study also provided a scientific basis for the improvement of official monographs in pharmacopoeias.

Methods

The impurity profiles and polymerized impurity in mezlocillin were studied by multiple heart‐cutting two‐dimensional liquid chromatography coupled with ion trap time‐of‐flight mass spectrometry (2D‐LC/IT‐TOF MS) in both positive and negative modes of electrospray ionization. Target eluents from the first dimensional chromatography with a non‐volatile mobile phase were trapped and sent to the second dimensional chromatography with a volatile mobile phase by a switching valve. The structures of the impurities in the mezlocillin drug substance were deduced based on the high‐resolution MSn data.

Results

In the environment of water, oxygen, high temperature, acid and base, a series of degradation products could be easily produced from mezlocillin. Mezlocillin was hydrolyzed into impurities I, IV, V and X, and was degraded into impurity III by methanolysis. Mezlocillin was oxidized into sulfoxide by producing impurity XI. Furthermore, impurities VI, VII, VII and IX were all isomers of mezlocillin. The proposed formation pathways of these products were demonstrated in this study.

Conclusions

Eleven degradation impurities and one polymerized impurity in mezlocillin were separated and characterized. Based on characterization of impurities, this study discovered the mechanism of impurity production and provided guidance for manufacturers to improve the process and storage conditions and reduce levels of impurities.
Identification of absorbed components and their metabolites in rat plasma after oral administration of Shufeng Jiedu capsule using ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry
Authors: Liu Xinyi , Zhang Hongbing , Xu Jun , Gong Suxiao , Han Yanqi , Zhang Tiejun , Liu Changxiao
Published: May 2019

Rationale

Shufeng Jiedu capsule (SFJDC), a prescription of traditional Chinese medicine, is mainly used for the treatment of acute upper respiratory tract infections. However, the bioactive components remain unclear, which partly limits its quality control and further development. This work aimed to carry out a study of plasma pharmacochemistry to identify the potential bioactive components of SFJDC.

Methods

An effective approach based on a combination of ultra‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry (UPLC/QTOF‐MS) and multivariate statistical analysis was applied to comprehensively analyze the absorbed components and their metabolites in rat plasma after oral administration of SFJDC. After UPLC/QTOF‐MS detection, the differences between control and dosed plasma samples were distinguished by multivariate statistical analysis, and chromatographic signals of xenobiotic compounds were further extracted to identify structures.

Results

A total of 46 SFJDC‐related xenobiotic compounds were identified as potential bioactive components in rat plasma. Among these, 27 absorbed prototype constituents were mainly flavonoids, anthraquinones, stilbenes, iridoids, lignans, naphthalenes, phenylethanoid glycosides and triterpenoid saponins. Especially for hastatoside, verbenalin, forsythoside A, phillyrin and emodin, they were closely related to the anti‐inflammatory effect of SFJDC.

Conclusions

The absorbed components and metabolites of SFJDC in rat plasma were analyzed for the first time. This study will be conducive for ascertaining the quality markers of SFJDC for quality control and pharmacological mechanism research at the molecular level.
Preliminary investigation of aluminium fluoride complexes in aqueous solutions with capillary electrophoresis coupled with electrospray ionization mass spectrometry and with inductively coupled plasma mass spectrometry
Authors: Tanaka Miho , Hoshino Yoko , Nakamoto Daisuke
Published: May 2019

Rationale

It is crucial to identify and confirm the original species of aluminium ions (Al3+) dissolved in water, since they behave differently. Depending on their species, the toxicity differs. Capillary electrophoresis (CE) coupled with electrospray ionization mass spectrometry (ESI‐MS) and CE coupled with inductively coupled plasma mass spectrometry (CE/ICP‐MS) were explored to identify and determine simple systems of Al species solutions at pH 3.0.

Methods

The new combinations of techniques, namely, ESI‐MS coupled with CE for identification of species and ICP‐MS coupled with CE for confirmation, were appliedtofor the analyses of Al and fluoride (F) solutions.

Results

Al monomers, some Al dimers and trimers were detected by CE/ESI‐MS. CE/ICP‐MS experiments were conducted with the assembled interface. As a result, the calibration line showed R2 = 0.9856, and the detection limits were 35 nL and 0.037 μM. The results were compared with data obtained using MINEQL+.

Conclusions

Most of the Al species detected were monomers; some dimers and trimers were detected by CE/ESI‐MS, but they were not detected by CE‐ICP‐MS, probably owing to extremely low concentrations. The Al speciation technique was improved by CE/ESI‐MS, and the Al species present at extremely low concentrations were ascertained by CE/ICP‐MS. The use of coupled instruments will be one of the most powerful tools for identifying dissolved metal ions.
Quantitative Structure Activity Relationships Study of Soluble Epoxide Hydrolase Inhibitors Using MLR, ANN, CoMFA and CoMSIA Methods
Authors: Nazari Maryam , Tabatabai Sayyed Abbas , Rezaee Elham
Published: May 2019

Soluble epoxide hydrolase (sEH), a member of the α/β hydrolase fold family, catalyzes the hydrolysis of epoxy eicosatrienoic acids to vicinal diol which are involved in the regulation of blood pressure and inflammation. In this study, 2D and 3D‐QSAR analysis of novel N,N′‐disubstituted urea derivatives as sEH inhibitors were performed by stepwise multiple linear regressions (SW‐MLR), stepwise artificial neural networks (SW‐ANN), Comparative Molecular Field Analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA). It was found that SW‐MLR model with r2 of 0.954 for the training set and r2 of 0.876 for the test set were more favorable than model established by CoMFA method with r2=0.983, r2pred=0.602 and CoMSIA with r2=0.987, r2pred=0.751 in 3D‐QSAR. In addition, obtaining models were validated by cross validation with cut off value of q2> 0.5. These developed models could be a useful guideline to design and predict the activity of novel compounds with enhanced sEH inhibitory activities.
Design and Synthesis of Novel Functionalized Fused Oxazepine and Diazepine Analogues Containing Coumarin Backbone through Domino Reaction
Authors: Poursan Samane , Ahadi Somayeh , Balalaie Saeed , Rominger Frank , Bijanzadeh Hamid Reza
Published: May 2019

A simple and straightforward approach has been developed for the synthesis of functionalized fused oxazepine and diazepine analogues containing coumarin backbone. The approach was done through three‐component reaction of 4‐chloro‐3‐formylcoumarin, triphenyl‐λ5‐phosphanylidene derivatives and 2‐aminophenol or o‐phenylenediamine derivatives in the presence of cesium carbonate at room temperature. Carrying out the same reaction without base led to 4‐aminoarylcoumarins. Mild reaction conditions and synthesis of fused functionalized heterocyclic backbones are advantages of this approach.
Synthesis and Characterization of 5,10,15,20‐Tetrakis(4‐ethylphenyl)porphyrin and (Zn2+, Mn2+, Sn2+, Ni2+, Al3+, V3+)‐Derivatives: Photophysical and DFT study
Authors: Espitia‐Almeida Fabian , Díaz‐Uribe Carlos , Vallejo William , Gómez‐Camargo Doris , Romero‐Bohorquez Arnold R. , Schott Eduardo , Zarate Ximena
Published: May 2019

A novel family of porphyrins based on 5,10,15,20‐Tetrakis(4‐ethylphenyl)porphyrin (1) and six metallo‐derivatives (Zn2+(2), Sn2+(3), Mn2+ (4), Ni2+ (5), Al3+ (6) and V3+ (7)) were synthesized via the Alder‐cols method (synthesis yield between 59%‐75%) and characterized through 1H‐ and 13C‐ NMR, MALDI‐TOF mass spectrometry and FT‐IR assay. Photophysical study was carried out by UV‐Vis and fluorescence spectrophotometry with the aim of assessing their potential as dye sensitizers for photodynamic therapy (PDT). In this regard, fluorescence quantum yield values are between 0.002‐0.38, being the macrocycle 3, the porphyrin with the highest fluorescence quantum yield while the derivative 7 showed the lowest value. Quantum chemical calculations were carried out to study the molecular structure of the porphyrins and to get insight of the luminescent process for 1, which is the free metal system and 3 which includes Sn2+ as metal center. Results indicated that the emissive states involve the transitions with LLCT character for 1, while for 3 it is ML–LCT. This fact evidenced the metal effects on their photophysical properties. Finally, optical and spectroscopic properties and besides, DFT study suggest that 3 could be used as sensitizer in photodynamic therapy applications.
Monochlorotriazinyl‐β‐cyclodextrin Grafted on Graphene Oxide as an Attractive Green Heterogeneous Nanoreactor for Selective Oxidation Reaction with NBS in Water
Authors: Pour Shadi Rasoul , Dinari Mohammad , Abdolmaleki Amir
Published: May 2019

Graphene oxide supported monochlorotriazinyl‐β‐cyclodextrin (GO‐MCT‐ β‐CD) as a green nanoreactor was synthesized via a simple chemical bonding method and analyzed by XRD, FT‐IR, CHNS, FESEM and Raman spectroscopy. The prepared GO‐MCT‐β‐CD worked as a nanoreactor for the green oxidation reactions of benzyl alcohol derivatives with N‐bromo succinimide to their corresponding aldehydes under green conditions. Depending on the different substituents of various benzyl alcohols, good to excellent yields were obtained and no over‐oxidation was observed. It can be considered an attractive methodology due to the use of water in the presence of “solid metal‐free nanoreactor” as a green reaction system at the room temperature. Easy separation and excellent reusability of the catalyst were other advantages of this methodology.
Electrochemical Determination of Ascorbic Acid Based on AgNPs/PVP‐Modified Glassy Carbon Electrode
Authors: Karaboduk Kuddusi
Published: May 2019

The electrochemical determination of ascorbic acid was carried out at the surface of glassy carbon electrode (GCE) modified by silver nanoparticles (AgNPs):Polyvinylpyrrolidone (PVP). Nanocomposite was evaluated by fourier transform infrared spectroscopy, zeta potential, and X‐ray diffraction. Also, the surface morphologies of the developed electrode were investigated by scanning electron microscopy, and profilometer. The electrochemical performance of AgNPs/PVP/GCE was studied with cyclic voltammetry and electrochemical impedance spectroscopy measurements. The electrochemical studies demonstrated that the electrode had a large surface. Compared with the bare GCE, PVP/GCE, and AgNPs/GCE, the AgNPs/PVP‐modified GCE showed excellent performance for the electrochemical determination of ascorbic acid. At the optimized conditions of differential pulse voltammetry in pH 6.0 of phosphate buffer solution, the modified electrode allowed the determination of ascorbic acid on a potential of 0.54 V vs. Ag/AgCl. Under optimized conditions, the low detection limit of 0.047 μM and working range of 0.2‐1200 μM were obtained at the AgNPs/PVP/GCE. The AgNPs/PVP/GCE allowed to obtain highest peak current values at low concentrations. Moreover, the fabricated electrode also exhibited good repeatability, reproducibility, and stability. The developed electrode was successfully enforced for the analysis of ascorbic acid in banana, kiwi fruit, mango, and pineapple.
Investigating the Properties of Coil Tail in Ti–Nb–Mo Microalloyed Hot‐Rolled Strip
Authors: Gan Xiaolong , Yuan Qing , Zhao Gang , Hu Haijiang , Tian Junyu , Xu Guang
Published: May 2019

In the present study, the thermo‐mechanical controlled processing (TMCP) technology was applied to produce Ti–Nb–Mo microalloyed hot‐rolled steels. The strength at the tail of a strip coil is often found to be non‐uniform. The microstructural and the mechanical properties of the specimens in the outermost circle as well as in the third circle and the fifth circle from the outermost circle were analyzed in detail. The optical microscopy (OM) and the electron backscatter diffraction (EBSD) techniques are employed for the characterization of ferrite grains and grain boundaries. The precipitates were revealed by high‐resolution transmission electron microscopy (HR‐TEM) and energy dispersive spectroscopy (EDS). It is found that the precipitation strengthening induced by nano‐scale (Ti, Nb, Mo)C particles was the dominant factor for the disparity in properties in different positions of the coil tail. The volume fraction of nano‐scale (Ti, Nb, Mo)C particles increases from 0.220% in the outermost circle to 0.343% in the fifth circle. In addition, the lattice planes of (110)α and (100)(Ti, Nb, Mo)C followed a Baker‐Nutting orientation relationship. Nano‐scale (Ti, Nb, Mo)C particles mainly precipitated in ferrite grains during coiling and subsequent cooling. Furthermore, different cooling rates along the strip had inconspicuous influences on the grain size and lengths of ferrite grain boundaries.
Kinetics of Carbon Partitioning during Non‐Isothermal Treatment and Mechanical Properties of the First Industrial Coils of Hot Rolled Quenched and Partitioned Steel
Authors: Li Yun Jie , Chen Dong , Kang Jian , Li Xiao Lei , Yuan Guo , Misra Raja Devesh Kumar , Wang Guo Dong
Published: May 2019

In this study, an energy‐efficient processing route involving hot rolling, direct quenching, and air cooling partitioning (DQ&P) is proposed for the large‐scale industrial production. The carbon partitioning is completed through waste heat of the steel coils. The effect of quenching temperature (QT) and the kinetics of non‐isothermal carbon partitioning were investigated in a low carbon steel 0.19C‐1.5Si‐1.6Mn (wt%). A stable volume fraction of retained austenite (RA) ≈11.1–13.5% is obtained in the QT range of ≈240–360 °C, which provides a wide quenching window for industrial production. In addition, when the QT was 320 °C, the carbon partitioning was adequate at cooing rate of less than 1 °C s−1 and the volume fraction of RA was more than 11%. When the cooling rate is increased to 5 and 10 °C s−1, ≈10% RA with high carbon content of ≈1.3 wt% is interestingly obtained. A large scale industrial coils of hot Q&P (Quenched and Partitioned) steel is successfully produced using a commercial steel 0.13C‐1.2Si‐1.5Mn‐0.25Cr (wt%). The mechanical properties are uniform for the entire steel coil with tensile strength of ≈1258–1319 MPa and total elongation of ≈13.7–16%. The present work confirms the viability to introduce Q&P process in the hot rolling production line.
Qualification and design of anchor channels with channel bolts according to the new EN 1992‐4 and ACI 318
Authors: Mahrenholtz Christoph , Sharma Akanshu
Published: May 2019

Though anchor channels with channel bolts are used in practice since long time, the codification of their design rules was just recently finalized in Europe with the issuing of the new EN 1992‐4. In the United States, full consolidation of the design rules for anchor channels with channel bolts in ACI 318 is yet to be included. The design requires product‐specific design data that are provided in qualification certificates. Qualification is carried out in Europe and in the United States according to published qualification guidelines. Currently, the qualification guidelines and design rules are not fully harmonized between Europe and the United States, sometimes resulting in significantly different design outcomes. This paper describes the framework of qualification and design, provides a comprehensive compendium of all design rules required for anchor channel‐channel bolt‐systems, and points out the differences between Europe and the United States with regard to qualification and design.
Effect of Lactobacillus paracasei A221‐fermented ginseng on impaired spatial memory in a rat model with cerebral ischemia and β‐amyloid injection
Authors: Nagao Masaki , Yamano Satoshi , Imagawa Naoki , Igami Kentaro , Miyazaki Toshitsugu , Ito Hisatomi , Watanabe Takuya , Kubota Kaori , Katsurabayashi Shutaro , Iwasaki Katsunori
Published: May 2019

Aim

Ginseng, a traditional herbal medicine, has been shown to prevent the progression of dementia, but its therapeutic effects vary because ginseng's components must first be activated by intestinal bacteria before being absorbed into the blood. We therefore focused on a fermented ginseng (FG), which contains activated components prepared by Lactobacillus paracasei A221, and compared its effects with those of non‐FG. In this study, we investigated whether FG is effective on spatial memory impairment in rats.

Methods

Rats with spatial memory impairment were prepared with transient cerebral ischemia and intraventricular injection of β‐amyloid 1‐42 for 7 days (CI + Aβ). Oral FG or non‐FG was given for 7 days after the cerebral ischemia. Spatial memory was evaluated using the Morris water maze (MWM). We observed neuronal neuclei‐positive cells to assess hippocampal neuron loss, and investigated the protein expression of caspase‐3 and cleaved caspase‐3 for neuronal apoptosis, ionized calcium‐binding adapter molecule 1 (Iba‐1) for microglia, and glial fibrillary acidic protein for astrocytes.

Results

FG treatment in the CI + Aβ‐operated rats shortened the extended time to reach the platform in the MWM, whereas non‐FG treatment did not affect the extended time. FG ameliorated loss of hippocampal cornu amonis (CA)1 neurons and the increase in caspase‐3 and Iba‐1 in the CI + Aβ‐operated rats.

Conclusion

FG improved spatial memory impairment in CI + Aβ‐operated rats. The effect of FG might be attributed to the amelioration of apoptotic neuronal cell death and the inactivation of microglia. FG is a more useful treatment for patients with cognitive dysfunction than non‐FG.
Detection of equid herpesviruses among different Arabian horse populations in Egypt
Authors: Azab Walid , Bedair Sameh , Abdelgawad Azza , Eschke Kathrin , Farag Gemelat K. , Abdel‐Raheim Ali , Greenwood Alex D. , Osterrieder Nikolaus , Ali Ahmed A. H.
Published: May 2019

Equid herpesviruses (EHVs) threaten equine health and can cause significant economic losses to the equine industry worldwide. Different equid herpesviruses, EHV‐1, EHV‐2, EHV‐4 and EHV5 are regularly detected among horse populations. In Egypt, monitoring is sporadic but EHV‐1 or EHV‐4 have been reported to circulate in the horse population. However, there is a lack of reports related to infection and health status of horses, likely due to the absence of regular diagnostic procedures. In the current study, the circulation of four infectious equid herpesviruses (EHV‐1, EHV‐2, EHV‐4 and EHV‐5) among different Arabian horse populations and donkeys residing the same farm was monitored. Different samples were collected and DNA was extracted and subjected to quantitative (q)‐PCR to detect the four equid herpesviruses using specific primers and probes. Antibody titres against EHV‐1 and EHV‐4 were tested using virus neutralization test and type‐specific ELISA. The results showed that EHV‐1, EHV‐2, EHV‐4 and EHV‐5 are endemic and can be a continuous threat for horses in the absence of vaccination programs and frequent virus reactivation. There is an urgent need for introduction of active regular surveillance measures to investigate the presence of different equid herpesviruses, and other equine viral pathogens, in various horse populations around Egypt and to establish a standardized cataloguing of equine health status.
Retracted: Synthesis, Crystal Structures, and Anti‐cervical Cancer Activity Evaluation of Three Trinuclear Transition Metal(II) Complexes with N,O‐Donor Schiff Base Ligand
Authors: Luo Teng‐Fei , Ji Xiao‐Feng , Zhu Cheng‐Yi
Published: May 2019

A new bi‐nucleating Schiff base ligand, 2‐(((3‐(dimethylamino)propyl)imino)methyl)‐6‐methoxyphenol (HL1) was prepared by a one‐pot condensation reaction, which was further used in the construction of three trinuclear Schiff base transition metal(II) complexes [Cu3(L1)2(OH)2(H2O)2](NO3)2 (1), [Co3(L1)2(OH)2(H2O)2](NO3)2 (2), and [Cu3(L1)2(N3)4] (3). Furthermore, a green hand grinding technique was implemented to reduce the particle size of the coordination complexes to generate the nanoscale compounds. The SEM studies reveal the formation of square and spherical particles for nano 1 and 2, and nanorod for nano 3. In addition, the anti‐proliferation activity of nano 1–3 was detected on the human cervical cancer Hela cells with CCK‐8 assay. The cell viability curves and IC50 values indicated that only nano 1 has anti‐proliferation activity on Hela cells. To further investigate the mechanism of nano 1 induced Hela cell death, the Annexin V‐FITC/PI double staining assay, western blot assay, and ROS level detection was conducted.
A Flexible, Extremely Sterically Demanding Triazenide Ligand: Synthesis and Coordination Chemistry
Authors: Gyton Matthew R. , Bhadbhade Mohan , Cole Marcus L.
Published: May 2019

Seeking to further the investigation of extremely sterically congested main group metals, the synthesis of a new oligoaryl triazene (Dipp*2N3H) is reported. This was accessed by diazotization of Dipp*NH2 to access both Dipp*I and Dipp*N3 in high yield and with scalable preparations. These compounds are used as precursors to Dipp*2N3H, via a magnesium aryl, due to the difficulties in obtaining pure triazene via an aryl‐lithium species. Deprotonation of the triazene with both potassium and thallium tert‐butoxides gives the respective metal triazenides in high yield. The solid‐state structures of these complexes have been determined and three high hapticity metal arene‐π interactions, which sterically shield the metal centers, were observed in each case; spectroscopic C2v symmetry suggests these interactions are fluxional in solution. The variability of these interactions in the solid state as well as the changes in calculated steric demand of the ligand between metals point to an adaptive, flexible coordination mode.
Scope of self-interacting thermal WIMPs in a minimal U(1)D extension and its future prospects
Authors: Barman Rahool Kumar , Bhattacherjee Biplob , Chatterjee Arindam , Choudhury Arghya , Gupta Aritra
Published: May 2019

Abstract

In this work we have considered a minimal extension of Standard Model by a local U(1) gauge group in order to accommodate a stable (fermionic) Dark Matter (DM) candidate. We have focussed on parameter regions where DM possesses adequate self-interaction, owing to the presence of a light scalar mediator (the dark Higgs), alleviating some of the tensions in the small-scale structures. We have studied the scenario in the light of a variety of data, mostly from dark matter direct searches, collider searches and flavor physics experiments, with an attempt to constrain the interactions of the standard model (SM) particles with the ones in the Dark Sector (DS). Assuming a small gauge kinetic mixing parameter, we find that for rather heavy DM the most stringent bound on the mixing angle of the Dark Higgs with the SM Higgs boson comes from dark matter direct detection experiments, while for lighter DM, LHC constraints become more relevant. Note that, due to the presence of very light mediators, the effective operator approach to the direct detection is inapplicable here and these constraints have been re-evaluated for our scenario. In addition, we find that the smallness of the relevant portal couplings, as dictated by data, critically suppress the viability of DM production by the standard “freeze-out” mechanism in such simplified scenarios. In particular, the viable DM masses are$$ \lesssim \mathcal{O}(2) $$≲O2GeV i.e. in the regions where direct detection limits tend to become weak. For heavier DM with large self-interactions, we hence conclude that non-thermal production mechanisms are favored. Lastly, future collider reach of such a simplified scenario has also been studied in detail.
The impact of gasification temperature on the process characteristics of sorption enhanced reforming of biomass
Authors: Fuchs J. , Schmid J. C. , Müller S. , Mauerhofer A. M. , Benedikt F. , Hofbauer H.
Published: May 2019

Especially carbon-intensive industries are interested in a decarbonization of their processes. A technology, which can contribute to a significant reduction of the carbon footprint, is the so-called sorption enhanced reforming process. The sorption enhanced reforming process uses a dual fluidized bed reactor system with limestone as a bed material for the thermochemical conversion of biomass into a valuable nitrogen-free product gas. This product gas can be used for further synthesis processes like methanation. The dependency of the product gas composition on the gasification temperature is already a well-known fact. Nevertheless, detailed investigations and models of the effect on elemental balances (especially carbon) of the process are missing in the literature and are presented in this work. Therefore, previously published data from different pilot plants is summarized and is discussed on a mass balance. Based on this information, investigations on the product gas equilibrium composition are presented and conclusions are drawn: it can be shown that the sorption enhanced reforming process can be divided into two sub-processes, namely “carbonation dominated sorption enhanced reforming” and “water-gas shift dominated sorption enhanced reforming.” The sub-process carbonation dominated SER is characterized by a high deviation from the water-gas shift equilibrium and a nearly constant CO content in the product gas over gasification temperature (< 700 °C). The sub-process water-gas shift dominated SER can be identified by a steep increase of the CO content in the product gas over temperature and nearly equilibrium state of the water-gas shift reaction (700–760 °C).
Universal screening program for lipid disorders in 2-10 years old Lebanese children
Authors: Georges Nicolas , Simon Akiki , Naim Bassil , Georges Nawfal , Georges Abi Fares , Tanios Akiki
Published: May 2019

Introduction

Dyslipidemia has been recognized as a risk factor for cardiovascular diseases. Studies have showed that the development of atherosclerotic lesions begins in childhood and progresses throughout life. While the prevalence of dyslipidemia in adults has been reported to be 10 times higher in Lebanon compared to Western countries, data on the prevalence of dyslipidemic children in Lebanon is lacking.

Objectives

This study was conducted to assess the benefit of a protocol for universal screening for lipid disorders in Lebanese children aged between two and ten years old.

Materials and methods

A total of four hundred children aged 2–10 years old (51.5% boys) were included in the study. The subjects were recruited from private pediatric clinics after parental consent. Fasting total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL), high density lipoprotein (HDL) levels were measured and non-HDL cholesterol was calculated. The values were categorized according to 2011 Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents.

Results

The overall prevalence of high TC (≥200 mg/dL), high non-HDL-C (≥145 mg/dL), high LDL (≥130 mg/dL), high TG (≥100 mg/dL) and low HDL (<40 mg/dL) was respectively 19.5%, 23%, 19%, 31.8% and 20%. The overall frequency of dyslipidemia was 51.7%. In a bivariate analysis, dyslipidemia in children was associated with a BMI ≥95th percentile and parents having TC > 240 mg/dL with a P value respectively of .006 and .0001. Furthermore, high TG was independently associated with a BMI ≥95th percentile (P = .0001). Children with parents having TC > 240 mg/dL was significantly correlated with high TC, high non-HDL-C and high LDL (P = .0001 for all variables). Finally, according to the Pediatric Dyslipidemia Screening Guidelines from the 2011 Expert Panel, 62.3% of dyslipidemic children had at least 1 risk factor that qualified them for screening while 37.7% of them didn't have any risk factor.

Conclusions

It is preferable to review the latest pediatric dyslipidemia screening guidelines by performing a universal screening program since a third of our dyslipidemic Lebanese children will be missed.