bluuebunny/crossref_metadata_2025 huggingface dataset:
Mass‐dependent parameters of extensive air showers with anomalous longitudinal profiles
Authors: Novotný V. , Nosek D. , Blažek J.
Published: March 2019

We investigate possibilities to determine the mass of a primary particle from anomalous longitudinal profiles of extensive air showers. Such profiles are predicted utilizing a Monte Carlo technique together with the contemporary high‐energy interaction models. The depth of shower maximum, which is commonly used for the mass composition analyses, is inspected and its performance to discriminate between primary species is studied. We search for alternative observables that have better properties in the case of anomalous profiles.
Interphases in Electroactive Suspension Systems: Where Chemistry Meets Mesoscale Physics
Authors: Shukla Garima , Franco Alejandro A.
Published: March 2019

Semi‐solid redox flow batteries (SSRFBs) consist of electrochemically active particle suspensions as electrodes and can potentially be applied to large scale energy storage. Invented just a decade ago, these batteries already face dwindling commercial value as they can be too complex to study systematically. This review illustrates the depth and width of the state of the art of knowledge that needs to be taken into account. Additionally, this work shows how SSRFBs are an embodiment of complex systems. Conventional theoretical paradigms, experimental tools, and modeling methods generally reduce the size of the problem to solve it. However, this is nearly impossible for highly complex systems with interdependent parameter relationships. This review shows how rheology plays a very significant role in impacting electrochemistry. It concluds that the fastest way to optimize SSRFBs is by obtaining as many experimentally observable parameters as possible using advanced simultaneous techniques, followed by incorporation of this multidisciplinary data into a unified theoretical framework.
Prevalence of selected birth defects by maternal nativity status, United States, 1999–2007
Authors: Kirby Russell S. , Mai Cara T. , Wingate Martha S. , Janevic Teresa , Copeland Glenn E. , Flood Timothy J. , Isenburg Jennifer , Canfield Mark A. ,   for the National Birth Defects Prevention Network
Published: March 2019

Objectives

We investigated differences in prevalence of major birth defects by maternal nativity within racial/ethnic groups for 27 major birth defects.

Methods

Data from 11 population‐based birth defects surveillance systems in the United States including almost 13 million live births (approximately a third of U.S. births) during 1999–2007 were pooled. We calculated prevalence estimates for each birth defect for five racial/ethnic groups. Using Poisson regression, crude and adjusted prevalence ratios (aPRs) were also calculated using births to US‐born mothers as the referent group in each racial/ethnic group.

Results

Approximately 20% of case mothers and 26% of all mothers were foreign‐born. Elevated aPRs for infants with foreign‐born mothers were found for spina bifida and trisomy 13, 18, and 21, while lower prevalence patterns were found for pyloric stenosis, gastroschisis, and hypospadias.

Conclusions

This study demonstrates that birth defects prevalence varies by nativity within race/ethnic groups, with elevated prevalence ratios for some specific conditions and lower prevalence for others. More detailed analyses focusing on a broader range of maternal behaviors and characteristics are required to fully understand the implications of our findings.
Frequency‐dependent current perception threshold in healthy Japanese adults
Authors: Nakatani‐Enomoto Setsu , Yamazaki Madoka , Kamimura Yoshitsugu , Abe Mitsunari , Asano Kohei , Enomoto Hiroyuki , Wake Kanako , Watanabe Soichi , Ugawa Yoshikazu
Published: March 2019

The purpose of the study involves measuring the threshold for electric currents (i.e., current perception threshold or CPT) under several stimulating current frequencies. Specifically, current perception threshold (CPT) was measured in 53 healthy volunteers between the ages of 21 and 67. The stimulation currents were applied on the right index finger with stimulus frequencies in the range of 50 Hz − 300 kHz. The method of limits and method of constant stimuli were combined to measure the CPT. In a manner consistent with the findings obtained by previous studies, the results indicated that CPT was higher in men than in women and in older individuals than in young subjects. Bioelectromagnetics. 9999:XX–XX, 2019. © 2019 Bioelectromagnetics Society.
Becoming electro‐hypersensitive: A replication study
Authors: Dieudonné Maël
Published: March 2019

Idiopathic Environmental Intolerance attributed to Electromagnetic Fields (IEI‐EMF) is an emerging environmental illness that is characterized by the attribution of various symptoms to electromagnetic fields (EMF). To date, research has not succeeded in objectifying the illness’ semiology or etiology. IEI‐EMF remains impossible to define other than in terms of the attributions of the persons affected. Yet, the genesis of these attributions is still not well understood. This study's objective is to replicate previous results relating to them, while correcting their limitations. Sixteen electro‐hypersensitive (EHS) subjects lent themselves to both a sociological interview and a medical interview, and completed a set of standardized questionnaires. Three distinct types of biographical trajectories leading to persons becoming convinced of their hypersensitivity were identified, which were called the Reticent Attribution model, the Prior Attribution model, and the By Proxy Attribution model. These three models of EHS attribution process do not appear to lead to clinically distinct forms of IEI‐EMF. What distinguishes them is the way in which the initial suspicion of the electromagnetic environment emerges. They demonstrate a diversification of the pathways to IEI‐EMF. Nonetheless, in each model, the learning process that enables the EHS attribution to be materialized and operationalized is identical. The ability to establish causation between the electromagnetic environment and their condition is therefore the result of EHS subjects’ trajectories, rather than their starting point. This observation is not congruent with models attributing IEI‐EMF to nocebo reactions, which raises the question of these models’ ecological validity. Bioelectromagnetics. 2019;9999:XX–XX. © 2019 Bioelectromagnetics Society.
Involvement of calcium in 50‐Hz magnetic field‐induced activation of sphingosine kinase 1 signaling pathway
Authors: Yang Xiaobo , Ye Anfang , Chen Liangjing , Xia Yongpeng , Jiang Wei , Sun Wenjun
Published: March 2019

Previously, we found that exposure to a 50‐Hz magnetic field (MF) could induce human amniotic epithelial (FL) cell proliferation and sphingosine kinase 1 (SK1) activation, but the mechanism was not clearly understood. In the present study, the possible signaling pathways which were involved in SK1 activation induced by 50‐Hz MF exposure were investigated. Results showed that MF exposure increased intracellular Ca2+ which was dependent on the L‐type calcium channel, and induced Ca2+‐dependent phosphorylation of extracellular regulated protein kinase (ERK), SK1, and protein kinase C α (PKCα). Also, treatment with U0126, an inhibitor of ERK, could block MF‐induced SK1 phosphorylation, but had no effect on PKCα phosphorylation. Also, the inhibitor of PKCα, Gö6976, had no effect on MF‐induced SK1 activation in FL cells. In addition, the activation of ERK and PKCα could be abolished by SKI II, the inhibitor of SK1. In conclusion, the intracellular Ca2+ mediated the 50‐Hz MF‐induced SK1 activation which enhanced PKCα phosphorylation, and there might be a feedback mechanism between SK1 and ERK activation in responding to MF exposure in FL cells. Bioelectromagnetics. 9999:XX–XX, 2019. © 2019 Bioelectromagnetics Society.
Too Many False Targets for MicroRNAs: Challenges and Pitfalls in Prediction of miRNA Targets and Their Gene Ontology in Model and Non‐model Organisms
Authors: Fridrich Arie , Hazan Yael , Moran Yehu
Published: March 2019

Short (“seed”) or extended base pairing between microRNAs (miRNAs) and their target RNAs enables post‐transcriptional silencing in many organisms. These interactions allow the computational prediction of potential targets. In model organisms, predicted targets are frequently validated experimentally; hence meaningful miRNA‐regulated processes are reported. However, in non‐models, these reports mostly rely on computational prediction alone. Many times, further bioinformatic analyses such as Gene Ontology (GO) enrichment are based on these in silico projections. Here such approaches are reviewed, their caveats are highlighted and the ease of picking false targets from predicted lists is demonstrated. Discoveries that shed new light on how miRNAs evolved to regulate targets in various phyletic groups are discussed, in addition to the pitfalls of target identification in non‐model organisms. The goal is to prevent the misuse of bioinformatic tools, as they cannot bypass the biological understanding of miRNA–target regulation.
Nucleotide Excision Repair and Transcription‐Associated Genome Instability
Authors: Apostolou Zivkos , Chatzinikolaou Georgia , Stratigi Kalliopi , Garinis George A.
Published: March 2019

Transcription is a potential threat to genome integrity, and transcription‐associated DNA damage must be repaired for proper messenger RNA (mRNA) synthesis and for cells to transmit their genome intact into progeny. For a wide range of structurally diverse DNA lesions, cells employ the highly conserved nucleotide excision repair (NER) pathway to restore their genome back to its native form. Recent evidence suggests that NER factors function, in addition to the canonical DNA repair mechanism, in processes that facilitate mRNA synthesis or shape the 3D chromatin architecture. Here, these findings are critically discussed and a working model that explains the puzzling clinical heterogeneity of NER syndromes highlighting the relevance of physiological, transcription‐associated DNA damage to mammalian development and disease is proposed.
Chronic pain after hand-assisted laparoscopic donor nephrectomy
Authors: Zorgdrager M , van Londen M , Westenberg L B , Nieuwenhuijs-Moeke G J , Lange J F M , de Borst M H , Bakker S J L , Leuvenink H G D , Pol R A
Published: March 2019

Background

Data on chronic pain after kidney donation are sparse. The aim of this study was to assess the incidence of chronic pain after hand-assisted laparoscopic nephrectomy.

Methods

Living kidney donors who donated between 2011 and 2017 at the University Medical Centre Groningen were included. All patients underwent hand-assisted laparoscopic donor nephrectomy. Postdonation pain and movement disabilities were assessed using the Carolinas Comfort Scale (CCS) and a visual analogue scale (VAS). The prevalence, severity of pain and the need for analgesics were reported.

Results

Some 333 living kidney donors with a mean age of 56 years were included. At a median of 19 (i.q.r. 10–33) months after donation, 82 donors (24·6 per cent) had a CCS score above 0, of which 58 (71 per cent) had a CCS score of at least 2 and 57 (70 per cent) reported movement limitations. Some 110 donors (33·0 per cent) had a VAS score of more than 0. Complaints mainly occurred during bending over (12·3 per cent) and exercising (12·4 per cent). Thirty-two donors (9·7 per cent) required analgesics during follow-up between donation and the time of measurement, and six of 82 (7 per cent) reported chronic inguinal pain. In multivariable analysis, donor age (odds ratio (OR) 0·97, 95 per cent c.i. 0·95 to 0·99; P = 0·020) and length of hospital stay (OR 1·21, 1·01 to 1·51; P = 0·041) were independently associated with chronic pain.

Conclusion

One-quarter of donors experienced chronic postdonation pain or discomfort, most of which was bothersome. Younger donors and those with a longer postoperative hospital stay had more symptoms.
Bacterial cellobiose metabolism: An inquiry‐driven, comprehensive undergraduate laboratory teaching approach to promote investigative learning
Authors: Periyannan Gopal R.
Published: March 2019

Technique‐centered biochemistry or molecular biology undergraduate laboratory curricula do not offer significant opportunities for thoughtful, in‐depth exploration of the science to foster investigative learning. To demonstrate inclusion of inquiry‐driven laboratory experiments into the undergraduate biochemistry and molecular biology curricula, a comprehensive set of laboratory experiments, covering several principles of biochemistry and molecular biology, have been developed under a single theme. The laboratory curriculum described here comprehensively investigates bacterial cellobiose metabolism using multiple biochemical, molecular biological (RNA isolation, RT‐PCR, PCR, and enzyme assay), and analytical techniques (High Performance Liquid Chromatography, NMR, spectrophotometry, and thin‐layer chromatography) to explore the principles of metabolomics and genomics in a single undergraduate laboratory course setting using Caulobacter crescentus as the model organism. This laboratory module serves as a model for educators to develop easy‐to‐implement laboratory curricula incorporating contemporary biochemistry and molecular biology concepts and techniques to provide a course‐based undergraduate research experiences (CUREs) with defined learning objectives. © 2019 International Union of Biochemistry and Molecular Biology, 47(4):438–445, 2019.
Intracerebral transplantation of erythropoietin‐producing fibroblasts facilitates neurogenesis and functional recovery in an ischemic stroke model
Authors: Chou Pin‐Chun , Tsai Yi‐Chieh , Chen Shiu‐Jau , Tsai Li‐Kai , Chien Chung‐Liang
Published: March 2019

Introduction

Erythropoietin (EPO) can enhance neurogenesis and fibroblasts can secrete growth factors; together, they may benefit ischemic stroke. We transplanted EPO‐producing fibroblasts into the rodent infarcted brain to test their effect on neurogenesis and functional recovery.

Methods

A total of 106 cells of EPO‐producing NIH/3T3 fibroblasts (EPO/EGFP/3T3) or enhanced green fluorescence protein (EGFP)‐expressing fibroblasts (EGFP/3T3) were stereotaxically injected into the infarcted striatum of adult rats that received transient middle cerebral artery occlusion (MCAO) surgery 1 day poststroke. On day 14 after MCAO, the animals were euthanized for the evaluation of neurogenesis via immunohistochemistry and of the expression of growth factors using enzyme‐linked immunosorbent assay. The infarct volume was analyzed using magnetic resonance imaging and the neurological behavior was assessed using the neurological severity scoring performed within 14 days after MCAO.

Results

The MCAO rats with EPO/EGFP/3T3 treatment showed high EPO expression in the infarcted brain for at least 1 week. The concentration of brain‐derived neurotrophic factor was higher in both hemispheres of MCAO rats with either EGFP/3T3 or EPO/EGFP/3T3 treatment at 14 days poststroke compared with untreated MCAO rats. The number of Ki‐67‐, nestin‐, or doublecortin‐immunoreactive cells in bilateral subventricular zones was higher in EPO/EGFP/3T3‐treated MCAO rats than it was in untreated MCAO control animals, indicating the enhancement of neurogenesis after EPO/EGFP/3T3 treatment. Notably, post‐MCAO EPO/EGFP/3T3 treatment significantly reduced infarct size and improved functional recovery.

Conclusion

The intracerebral transplantation of EPO‐producing fibroblasts benefited an ischemic stroke model probably via the enhancement of neurogenesis.
Does emotion matter? The role of alexithymia in violent recidivism: A systematic literature review
Authors: Leshem Rotem , van Lieshout Pascal H.H.M. , Ben‐David Sarah , Ben‐David Boaz M.
Published: March 2019

Background

Several variables have been evidenced for their association with violent reoffending. Resultant interventions have been suggested, yet the rate of recidivism remains high. Alexithymia, characterised by deficits in emotion processing and verbal expression, might interact with these other risk factors to affect outcomes.

Aim

Our goal was to examine the role of alexithymia as a possible moderator of risk factors for violent offender recidivism. Our hypothesis was that, albeit with other risk factors, alexithymia increases the risk of violent reoffending.

Method

We conducted a systematic literature review, using terms for alexithymia and violent offending and their intersection.

Results

(a) No study that directly tests the role of alexithymia in conjunction with other potential risk factors for recidivism and actual violent recidivism was uncovered. (b) Primarily alexithymia researchers and primarily researchers into violence have separately found several clinical features in common between aspects of alexithymia and violence, such as impulsivity (total n = 24 studies). (c) Other researchers have established a relationship between alexithymia and both dynamic and static risk factors for violent recidivism (n = 16 studies).

Conclusion

Alexithymia may be a possible moderator of risk of violent offence recidivism. Supplementing offenders' rehabilitation efforts with assessments of alexithymia may assist in designing individually tailored interventions to promote desistance among violent offenders.
Characteristics of abnormal post‐stent optical coherence tomography findings in hemodialysis patients
Authors: Matsuhiro Yutaka , Matsunaga‐Lee Yasuharu , Nakamura Daisuke , Yano Masamichi , Yamato Masaki , Egami Yasuyuki , Shutta Ryu , Sakata Yasushi , Nishino Masami , Tanouchi Jun
Published: March 2019

Aim

Clinical outcomes after percutaneous coronary intervention (PCI) in hemodialysis (HD) patients are significantly worse than those in non‐HD patients. Optical coherence tomography (OCT) is a high resolution imaging modality and provides a detailed assessment of post‐interventional abnormal findings that influence worse clinical outcomes. However, little is known about the abnormal post‐stent OCT findings in HD patients. Therefore, in this study, we compared the abnormal post‐stent OCT findings between HD and non‐HD patients.

Methods

One hundred thirty‐nine consecutive OCT guided PCI (21 lesions in HD patients and 118 lesions in non‐HD patients) were enrolled. We compared the post‐stent OCT findings, including the edge dissections, under expansion index (minimum stent area/mean reference area), and stent eccentricity index (minimum stent diameter/maximum stent diameter) between HD and non‐HD patients. We also compared the device‐oriented clinical events (DoCEs) at 8 months of follow up.

Results

There was a significantly higher prevalence of distal edge dissections (16.7% vs. 2.8%, P = 0.011) in HD patients. HD patients had a significantly lower under expansion index (0.76 ± 0.21 vs. 0.85 ± 0.14, P = 0.029) and stent eccentricity index (0.82 ± 0.09 vs. 0.88 ± 0.18, P = 0.018). The cumulative rate of DoCEs was significantly higher in the HD patients (23.8% vs. 5.2%, P = 0.013).

Conclusions

A higher prevalence of distal edge dissections, under expansion and stent eccentricity were detected by the detailed OCT findings in HD patients.
Transpedal vs. femoral access for peripheral arterial interventions—A single center experience
Authors: Shah Sooraj M. , Bortnick Anna , Bertrand Olivier F. , Costerousse Olivier , Htun Wah W. , Kwan Tak W.
Published: March 2019

Objective

To compare the transpedal approach to established femoral approach for endovascular treatment of infrainguinal peripheral arterial disease.

Background

Endovascular treatment of infrainguinal peripheral arterial disease is on the rise. Femoral approach is widely used but has significant complications. Recently the primary transpedal approach has been described for endovascular interventions. We hypothesized that transpedal approach could reduce access site related complications. We compared the two approaches in a retrospective cross‐sectional study at a single center.

Methods

We analyzed demographics, procedural parameters, and complications in patients who underwent a primary transpedal approach for infrainguinal intervention and compared to patients with a traditional femoral approach in our outpatient based endovascular lab.

Results

The success rate for access was lower in transpedal group compared to femoral (94% vs. 100%, p = .0002). The contrast dose (44 ± 11 mL vs. 68 ± 13 mL, p < .0001), radiation dose (25 mGy [16–43] vs. 48 mGy [36–67], p < .0001) and fluoroscopy time (5.48 min [3.48–11.71] vs. 9.35 min [6.63–14.11], p < .0001) were significantly lower in transpedal group.

Conclusion

The transpedal approach for infrainguinal revascularization appears to be a reasonable primary approach with high success and low complication rate with significant reduction in radiation and contrast dose. These findings should be further studied in a randomized controlled trial.
Successful repositioning of apically tethered transcatheter mitral valve replacement in the off‐bypass, beating heart
Authors: Aktuerk Dincer , Jansz Paul , Shaw Marty , Muller David W.M.
Published: March 2019

A 73‐year‐old man with severe, symptomatic secondary mitral regurgitation (MR) underwent successful transcatheter mitral valve replacement using the Tendyne™ mitral valve system. The device was deployed from the left ventricular (LV) apex and secured in position by a tether attached to an epicardial pad. Three days postoperatively, the patient developed hemolytic anemia and a paravalvular leak (PVL) associated with indentation of the LV apex. Adjustment of the tether tension and placement of an epicardial disc under the pad resulted in reduction in the PVL, and resolution of the hemolytic anemia.
A “minimalistic hybrid algorithm” in coronary chronic total occlusion revascularization: Procedural and clinical outcomes
Authors: Zivelonghi Carlo , van Kuijk Jan Peter , Poletti Enrico , Suttorp Maarten J. , Eefting Frank D. , Rensing Benno J. , ten Berg Jurrien M. , Colombo Antonio , Azzalini Lorenzo , Agostoni Pierfrancesco
Published: March 2019

Background

Percutaneous recanalization of coronary chronic total occlusions (CTOs) traditionally relies on the use of dual‐access and large bore catheters, with trans‐femoral approach adoption in most cases.

Objectives

Aim of this manuscript is to describe the outcomes of an alternative hybrid algorithm, called “Minimalistic Hybrid Algorithm,” which has the purpose to minimize the use of double access, large bore catheters, and femoral approach in order to minimize the risk of vascular complications and patient's discomfort, without compromising efficacy.

Methods

In this single‐center registry, a “minimalistic” approach was attempted in consecutive patients undergoing CTO PCI between March 2016 and October 2017. Data regarding the applicability of this algorithm and the related procedural success rates were collected, together with common demographic and angiographic characteristics.

Results

Of the 100 CTO PCI performed in the study period, 91(91%) were successfully approached according to the novel algorithm. Mean J‐CTO score of all minimalistic procedures was 1.9 ± 1.2, with 31(34%) patients presenting with J‐CTO score ≥3. In 52 procedures, the approach consisted of single‐catheter access, 49(94.2%) of which were trans‐radial. Out of the 39 patients approached with dual‐catheters, 26(69.2%) were biradial, and 8(21%) radial‐femoral. Procedural success in patients approached with the minimalistic algorithm was 89%, in line with the results of large‐multicenter experiences nowadays available.

Conclusions

Our results show that an alternative algorithm limiting the routine use of large bore catheters and trans‐femoral approach is feasible in the clinical practice and yields good procedural outcomes.
Functional properties of endosperm protein from size‐fractionated broken rice kernels generated after milling of parboiled and nonparboiled rice
Authors: Bruce Rebecca M. , Atungulu Griffiths G. , Hettiarachchy Navam S. , Horax Ronny
Published: March 2019

Background and objectives

The quantity and functionality of proteins in different sizes of broken rice (brokens) may inform the different pasting properties observed in rice flour derived from brokens. This study was conducted to determine properties of protein from size‐fractionated parboiled and nonparboiled milled broken rice kernels. In addition, the research sought to determine the extent to which properties of proteins influence functionality of rice flour derived from the studied brokens.

Findings

Whole kernels and medium brokens of nonparboiled rice recorded the highest quantity and yield of protein isolate, while the lowest was recorded in large brokens. A strong negative correlation existed between sample protein content and the size of parboiled brokens. Parboiled samples had decreased protein extractability than nonparboiled samples. Emulsifying activity (EA) of parboiled rice had a significantly strong negative linear association with size of brokens. Emulsifying stability (ES) on the other hand had a significantly strong positive linear association with size of brokens, and about 82% of the variation in ES was explained by size. The trend was opposite in the nonparboiled stream with ES having a strong negative linear association with size. A very strong positive linear association existed between foaming capacity (FC), foaming stability (FS), and size of nonparboiled samples. Surface hydrophobicity (SH) was significantly different among parboiled and nonparboiled rice, with weak positive correlations existing between SH and size of parboiled and nonparboiled samples. Solubility curves in nonparboiled stream were more uniform than the parboiled stream. Strong significant positive correlations existed between peak, trough, breakdown, final, setback viscosities, and ES. A strong positive linear association was observed between peak, trough, final viscosities, and FS. Differences in protein contents of whole kernels and size‐fractionated brokens may be attributed to either the variations in the distribution of inherent components of the kernel or variations in milling efficiency. Results in this research are specific for long‐grain hybrid rice and may vary depending on cultivar and environmental factors.

Conclusions

Proteins influence the pasting properties of brokens. Understanding the functional properties of size‐fractionated broken rice kernels from parboiled and nonparboiled streams is essential in directing the right kind of brokens to the right end‐use.

Significance and novelty

This study provides useful information to better utilization and value addition of brokens.
Immunotherapy of lidocaine allergy by intravenous desensitization using IFN‐gamma from a case: Overcoming impediments using IFN‐gamma during desensitization
Authors: Noh Geunwoong , Park Chul Ki , Ha Chang Won
Published: March 2019

Key Clinical Message

Anaphylactic reaction to lidocaine has been reported during a dental procedure. In this trial, a patient who required local anesthesia for dental treatment was desensitized successfully to intravenous lidocaine using IFN‐gamma. Practical general protocols and principles are suggested for the general application of this method for other intravenous drugs.
A Free‐Radical Reduction and Cyclization of Alkyl Halides Mediated by FeCl2
Authors: Pulikottil Feba Thomas , Pilli Ramadevi , Murugesan Vetrivelan , Krishnan Chandu G. , Rasappan Ramesh
Published: March 2019

Iron mediated catalytic reactions are of great interest in the field of organic synthesis because they are economic and naturally abundant. However, the use of iron catalyst in the field of free radical cyclization or reduction of alkyl halides remains limited. Here we describe the use of an unprecedented combination of iron and zinc in the reduction and 5‐exo‐trig radical cyclization of alkyl halides under mild condition in the absence of added ligands or additives. The method is distinguished by its wide scope, functional group tolerance and the use of 1,4‐cyclohexadiene as the source of hydrogen, which aids easy purification.
Purification of Nickel Sulfate by Batch Cooling Crystallization
Authors: Han Bing , Bøckman Oluf , Wilson Benjamin P. , Lundström Mari , Louhi-Kultanen Marjatta
Published: March 2019

Cooling crystallization was successfully carried out in a batch cooling crystallizer from impure acidic solutions to recover nickel as nickel sulfate salt with three different cooling rates. The compositions of the solutions included impurities of sodium, magnesium, chloride, and sulfuric acid to mimic industrial nickel electrowinning process solutions. The results show that NiSO4·6H2O mainly crystallized, and its solubility and purity decreased with the increase in the mass ratio of chloride to sulfate. Cooling rates did not have a significant influence on crystal purity; however, it did affect the filter cake moisture; lower moisture can be obtained with a lower cooling rate. The sequence of impurity removal efficiency from high to low was Cl > Na > Mg.
Simulation and Empirical Studies of Solvent Evaporation Rates in Vacuum Evaporation Crystallization
Authors: Said Arshe , Louhi-Kultanen Marjatta
Published: March 2019

Simulation results for continuous vacuum evaporation crystallization obtained by Aspen Plus and experimental results for semi‐batch vacuum evaporation crystallization are presented. In the crystallization experiments, the fixed heat duty was used to compare the water evaporation rates and crystal properties obtained at different pressures. The solution selected was aqueous glycine. It has the ability to form a number of different crystalline polymorphs, which allows it to exhibit a variety of different physical properties while maintaining its chemical properties. X‐ray diffraction results demonstrated that mainly the γ‐crystal form is produced under the conditions applied in vacuum evaporation crystallization.
Fluorine‐Doped Tin Oxide/Alumina as Long‐Term Robust Conducting Support for Earth‐Abundant Water Oxidation Electrocatalysts
Authors: Garcés‐Pineda Felipe A. , González‐Cobos Jesús , Torrens Mabel , Galán‐Mascarós José R.
Published: March 2019

In this work we apply a novel and simple methodology to develop a composite that consists of anodic aluminum oxide (AAO) covered by a fluorine‐doped tin oxide (FTO) film. The composite presents suitable morphological and electrical properties to be used as support for water electrooxidation catalysts based on non‐noble metals. AAO substrates were decorated with FTO via spray pyrolysis, followed by deposition of catalyst nanoparticles consisting of a cobalt‐analogue of Prussian Blue that promotes the oxygen evolution reaction. The electrodes were characterized by X‐ray Diffraction, Environmental Scanning Electron Microscopy and resistivity measurements. A promising electrocatalytic activity of the optimized AAO/FTO/PB electrode was observed at neutral pH and ambient conditions. The obtained results open a feasible strategy in the search for competitive water oxidation electrodes based on the combination of earth‐abundant metal catalysts on FTO‐covered anodized alumina supports.
Square Wave Voltcoulommetry Analysis of the Influence of the Electrostatic Environment on the Electrochemical Functionality of Redox Monolayers
Authors: Gonzalez Joaquin , Sequí Jose‐Alfonso
Published: March 2019

The analysis of effects of intermolecular interactions on square wave voltcoulommetric (SWVC) responses of electroactive monolayers under Nernstian conditions is presented. Theoretical expressions are given for the Faradaic and non‐Faradaic charge potential curves in terms of the potential perturbation variables and of the phenomenological interaction parameter G. Simple methods are proposed for determining the total excess of electroactive species, the apparent formal potential and the interaction parameter. The application of these methods to the analysis of the electrochemical behaviour of binary monolayers of ferrocenylundecanethiol/decanethiol at gold and platinum electrodes in two different non‐aqueous solvents allows us to obtain reliable values of the above parameters that clearly improve those determined by using Cyclic Voltammetry. Electrostatic insights into the interaction parameters is provided on the basis of a previously reported model. The importance of the presence of ion pairing processes in the value of the parameter G is discussed. The results obtained with SWVC technique point out the fact that intermolecular interactions are not avoided at low surface excesses of the redox probe, indicating that the impact of electrostatics in the appearance of non‐ideal electrochemical responses depends on the nature of the electrolytic media and on the structure of the monolayer in a complex way.
Ligand‐Based PCET Reduction in a Heteroleptic Ni(bpy)(dithiolene) Electrocatalyst Giving Rise to Higher Metal Basicity Required for Hydrogen Evolution
Authors: Koshiba Keita , Yamauchi Kosei , Sakai Ken
Published: March 2019

Proton abstraction leading to the formation of a hydride species required to evolve H2 largely relies on the basicity of d orbital of the metal responsible for this action. Here we report that a square‐planar NiII(bpy)(dcbdt) hydrogen evolution catalyst shows substantial acceleration in the proton abstraction rate due to the increased basicity at the filled Ni dz2 orbital after formation of [NiI(bpy−.)(dcbdt)]2− via consecutive two one‐electron reductions (bpy=2,2′‐bipyridine; dcbdt=4,5‐dicyanobenzene‐1,2‐dithiolate). The catalyst is likely to adopt the EECC′ mechanism in which the rate of the first protonation step is by far higher than that of the second step, even though an alternative path requiring another reduction (i. e., ECEC′) remains unexcluded. Our DFT calculations reveal that the first and second reductions are correlated with the electron injection into the metal‐ligand anti‐bonding and π*(bpy) orbitals, respectively, where the latter orbital shows non‐negligible hybridization with the nickel d orbital. In addition, a homoleptic catalyst [NiII(dcbdt)2]2− is shown to adopt the EC′EC mechanism with the rate‐determing step being a hydride forming step, consistent with the largely delocalized nature of the injected electron over the two dcbdt ligands (π*(dcbdt) orbital). This work demonstrates the importance of raising the basicity of the metal d orbital, relevant to promote the proton‐coupled electron transfer (PCET).
Efficient Syntheses of New Super Lewis Basic Tris(dialkylamino)‐Substituted Terpyridines and Comparison of Their Methyl Cation Affinities
Authors: Kleoff Merlin , Suhr Simon , Sarkar Biprajit , Zimmer Reinhold , Reissig Hans‐Ulrich , Marin‐Luna Marta , Zipse Hendrik
Published: March 2019

Syntheses of very electron‐rich dialkylamino‐substituted 2,2':6',2''‐terpyridines (TPYs) were adapted to moderate scale preparation without tedious purification of intermediates. The key 4'‐bromo‐6,6''‐dimethyl‐2,2':6',2''‐terpyridine‐4,4''‐diyl bisnonaflate is now available in gram quantities. Its nucleophilic aromatic substitution with dimethylamine provided mixtures of 4'‐bromo‐substituted 4,4''‐bis(dimethylamino)‐TPY and the tris(dimethylamino)‐TPY. The bromo compound was used in a Buchwald–Hartwig amination to provide the tris(dimethylamino)‐TPY in excellent yield. The 4'‐bromo substituent was reductively removed to furnish the bis(dimethylamino)‐TPY. The same sequence of reactions with pyrrolidine as nucleophile leads to the hitherto unknown pyrrolidino‐TPYs. Calculations at the MP2(FC)/6–31+G(2d,p)//B98/6‐31G(d) level predict very high methyl cation affinities for compounds of this type, with the 4,4',4''‐tri(pyrrolidin‐1‐yl)‐TPY being the most Lewis basic TPY synthesized to date. The efficiently prepared electron‐rich TPYs should be excellent ligands for many applications.
Synthesis and Self‐Assembly of Mixed‐Graft Block Copolymers
Authors: Le An N. , Liang Ruiqi , Zhong Mingjiang
Published: March 2019

Mixed‐graft block copolymers (mGBCPs) consist of two or more types of polymeric side chains grafted on a linear backbone in a random, alternating, or pseudo‐alternating sequence. They can phase‐separate with the backbone serving as the interface of the blocks, and the side chains dominate their self‐assembly behavior. mGBCPs are an accessible polymer architecture for exploring the idea of encoding polymer properties through the macromolecular architecture, as there are two distinct structural components that can be tuned: the backbone and the side chains. In this Concept article, the current literature on the synthesis of mGBCPs is reviewed, and the advantages and disadvantages of each synthetic method are noted. The self‐assembly of mGBCPs is also discussed where possible. Finally, directions for future research on mGBCP synthesis and self‐assembly are suggested.
Effect of substituents on the configurational stability of the stereogenic nitrogen in metal(II) complexes of α‐amino acid Schiff bases
Authors: Mei Haibo , Jean Marion , Albalat Muriel , Vanthuyne Nicolas , Roussel Christian , Moriwaki Hiroki , Yin Zizhen , Han Jianlin , Soloshonok Vadim A.
Published: March 2019

Herein, we report a general method for quantitative measurement of the configurational stability of the stereogenic nitrogen coordinated to M (II) in the corresponding square planar complexes. This stereochemical approach is quite sensitive to steric and electronic effects of the substituents and shown to work well for Ni(II), Pd(II), and Cu(II) complexes. Structural simplicity of the compounds used, coupled with high sensitivity and reliability of experimental procedures, bodes well for application of this approach in evaluation of chemical stability and stereochemical properties of newly designed chiral ligands for general asymmetric synthesis of tailor‐made amino acids.
Method for determination of optical purity of 2‐arylpropanoic acids using urea derivatives based on a 1,1′‐binaphthalene skeleton as chiral NMR solvating agents: Advantages and limitations thereof
Authors: Cuřínová Petra , Hájek Peter , Janků Kristýna , Holakovský Roman
Published: March 2019

Five optically active urea derivatives (1‐5) were used as NMR solvating agents for analysis of the optical purity of different 2‐arylpropanoic acids commonly used as nonsteroidal anti‐inflammatory drugs. These novel chiral solvating agents were more efficient at discriminating the respective enantiomers of targets than the chiral solvating agents known so far, without the need to add a base for achieving the signal splitting. The advantages and limits of the use of these novel chiral solvating agents were studied.
Online prediction of quality‐related variables for batch processes using a sequential phase partition method
Authors: Li Zheng , Wang Pu , Gao Xuejin , Qi Yongsheng , Chang Peng
Published: March 2019

Batch processes inherently have multiple operation phases; different phases exhibit different characteristics. Hence, it is reasonable to partition the process into phases and build sub‐phase models for online quality prediction. To this end, a sequential phase partition method based on the information increment is proposed. To address the multiphase behaviours in batch processes, this work utilizes a new information increment index to capture the dynamic characteristics of batch processes along a time direction and divides the process into sub‐phases. Next, phase‐based multiway partial least squares (MPLS) models are built to model within‐phase characteristics and predict the quality‐related variables online. Information increment is able to exploit the process evolution by focusing on the changing variable correlations derived from two adjacent extend time slice. It directly utilizes the available process measurements of successful history batch processes without data transformation or dimensionality reduction. The method is sequential and can overcome the limits of some phase partition methods that may divide the samples with discontinuous time sequence but similar characteristics into the same phase. In addition, the information increment is capable of reflecting the change of the process intuitively with high computation efficiency. Advantages of the proposed method are illustrated by two case studies, a penicillin simulation platform and an industrial application of Escherichia coli (E. coli) fermentation, respectively.
Structure and phase evolution of CaMnO3 perovskite during isothermal redox cycles
Authors: Yu Ningyu , Nair Mahesh Muraleedharan , Mahinpey Nader
Published: March 2019

Perovskite structured mixed metal oxides (ABO3) are one promising category of redox materials widely investigated for applications in various sustainable processes. In this study, we monitored the compositional and surface structural evolution of CaMnO3 under redox conditions at selected temperatures. The redox efficiency and stability of CaMnO3 was found to be temperature dependent. Despite enhanced sintering resistance and phase stability at 600 °C, the amount of oxygen release/uptake was low. At 750 °C, phase changes were found to diminish the redox efficiency in the long run. In contrast, at higher temperatures (900 °C) a stable oxygen uptake/release capacity was observed despite significant sintering and the associated structural and phase changes. The present study indicates that material composition and temperature determine the redox chemistry of CaMnO3 perovskite oxides. Interestingly, no noticeable amount of surface carbon deposition was detected under any stages of operation for this material.
Gas‐phase carbon coating of LiFePO4 nanoparticles in fluidized bed reactor
Authors: Sarbarze Samira Aghaee , Latifi Mohammad , Sauriol Pierre , Chaouki Jamal
Published: March 2019

Lithium iron phosphate (LiFePO4 or LFP) is a promising cathode material for large‐scale rechargeable lithium ion batteries. It suffers, however, from low ionic and low electronic conductivities. Size reduction to nanoparticles and uniform coating of conductive carbon overcome the conductivity issues. The conventional solid or liquid carbon coating processes drawbacks include the following: carbon excess; non‐uniform carbon layer; and undesired carbon type. Furthermore, economical liquid‐ and solid‐based carbon sources, being wastes derived from other industries, may also introduce impurities detrimental to the battery performance. This article presents a new fluidized bed chemical vapour deposition process (FB‐CVD) to coat carbon on LFP nanoparticles, with a secondary size representing particles of the Geldart's group B powders, through the pyrolysis of propylene. This gas‐phase process is used to overcome challenges in conventional carbon coating processes. Operating conditions including reaction time, gas residence time, reaction temperature, inlet concentration of propylene, and catalytic effect of LiFePO4 powders were investigated to produce C‐LiFePO4 (or C‐LFP) powders with desired mass and uniformity of coated carbon while avoiding sintering of the material. In addition, a mechanism for gas‐phase C‐LFP production from LFP is proposed.
Structurally Diverse Histone Deacetylase Photoreactive Probes: Design, Synthesis, and Photolabeling Studies in Live Cells and Tissue
Authors: Aboukhatwa Shaimaa M. , Hanigan Thomas W. , Taha Taha Y. , Neerasa Jayaprakash , Ranjan Rajeev , El‐Bastawissy Eman E. , Elkersh Mohamed A. , El‐Moselhy Tarek F. , Frasor Jonna , Mahmud Nadim , McLachlan Alan , Petukhov Pavel A.
Published: March 2019

Histone deacetylase (HDAC) activity is modulated in vivo by post‐translational modifications and formation of multiprotein complexes. Novel chemical tools to study how these factors affect engagement of HDAC isoforms by HDAC inhibitors (HDACi) in cells and tissues are needed. In this study, a synthetic strategy to access chemically diverse photoreactive probes (PRPs) was developed and used to prepare seven novel HDAC PRPs 9–15. The class I HDAC isoform engagement by PRPs was determined in biochemical assays and photolabeling experiments in live SET‐2, HepG2, HuH7, and HEK293T cell lines and in mouse liver tissue. Unlike the HDAC protein abundance and biochemical activity against recombinant HDACs, the chemotype of the PRPs and the type of cells were key in defining the engagement of HDAC isoforms in live cells. Our findings suggest that engagement of HDAC isoforms by HDACi in vivo may be substantially modulated in a cell‐ and tissue‐type‐dependent manner.
Molecular architecture of the zebra finch arcopallium
Authors: Mello Claudio V. , Kaser Taylor , Buckner Alexa A. , Wirthlin Morgan , Lovell Peter V.
Published: March 2019

The arcopallium, a key avian forebrain region, receives inputs from numerous brain areas and is a major source of descending sensory and motor projections. While there is evidence of arcopallial subdivisions, the internal organization or the arcopallium is not well understood. The arcopallium is also considered the avian homologue of mammalian deep cortical layers and/or amygdalar subdivisions, but one‐to‐one correspondences are controversial. Here we present a molecular characterization of the arcopallium in the zebra finch, a passerine songbird species and a major model organism for vocal learning studies. Based on in situ hybridization for arcopallial‐expressed transcripts (AQP1, C1QL3, CBLN2, CNTN4, CYP19A1, ESR1/2, FEZF2, MGP, NECAB2, PCP4, PVALB, SCN3B, SCUBE1, ZBTB20, and others) in comparison with cytoarchitectonic features, we have defined 20 distinct regions that can be grouped into six major domains (anterior, posterior, dorsal, ventral, medial, and intermediate arcopallium, respectively; AA, AP, AD, AV, AM, and AI). The data also help to establish the arcopallium as primarily pallial, support a unique topography of the arcopallium in passerines, highlight similarities between the vocal robust nucleus of the arcopallium (RA) and AI, and provide insights into the similarities and differences of cortical and amygdalar regions between birds and mammals. We also propose the use of AMV (instead of nucleus taenia/TnA), AMD, AD, and AI as initial steps toward a universal arcopallial nomenclature. Besides clarifying the internal organization of the arcopallium, the data provide a coherent basis for further functional and comparative studies of this complex avian brain region.
Is Excited‐State Aromaticity a Driving Force for Planarization of Dibenzannelated 8π‐Electron Heterocycles?
Authors: Toldo Josene , El Bakouri Ouissam , Solà Miquel , Norrby Per‐Ola , Ottosson Henrik
Published: March 2019

Compounds with dibenzannelated heterocycles with eight π‐electrons are found in a range of applications. These molecules often adopt a bent structure in the ground state (S0) but can become planar in the first excited states (S1and T1) because of the cyclically conjugated 4nπ central ring, which fulfils the requirements for excited state aromaticity. We report on a quantum chemical investigation of the aromatic character in the S1and T1states of dibenzannelated seven‐ and six‐membered heterocycles with one, two, or three heteroatoms in the 8π‐electron ring. These states could have ππ* or nπ* character. We find that compounds with one or two heteroatoms in the central ring have ππ* states as their S1and T1states. They are to a significant degree influenced by excited state aromaticity, and their optimal structures are planar or nearly planar. Among the heteroatoms, nitrogen provides for the strongest excited state aromaticity whereas oxygen provides for the weakest, following the established trend of the S0state. Yet, dibenzannelated seven‐membered‐ring compounds with N=N bonds have non‐aromatic nπ* states with strongly puckered structures as their S1and T1states.