bluuebunny/crossref_metadata_2025 huggingface dataset:
PER3 variable number tandem repeat (VNTR) polymorphism modulates the circadian variation of the descending pain modulatory system in healthy subjects
Authors: Carvalho Fabiana , Pedrazzoli Mario , Gasparin Assunta , dos Santos Franciele , Zortea Maxciel , Souza Andressa , da Silva Lucena Torres Iraci , Fregni Felipe , Caumo Wolnei
Published: June 2019

We evaluated the circadian pattern of variation of the descending pain modulatory system (DPMS) using a conditioned pain modulation (CPM) paradigm according to the variable-number tandem-repeat (VNTR) of the clock gene PER3 polymorphism. We assessed the relationship between the genotypes PER34/4 and PER35/5 and the temporal pattern of variation across the day using the following measures: the heat pain threshold (HPT), the cold pressure test (CPT), and the serum levels of BDNF and S100-B protein. The ∆-values (from afternoon to morning) of these measures were used for the analysis. The circadian phenotype was according to the mid-point sleep time established by the Munich ChronoType Questionnaire (MCTQ). We included 18 healthy volunteers (15 women) ages 18 to 30. A Generalized Linear Model (GLM) revealed a significant difference in the ∆-CPM-task between Per34/4 and Per35/5 genotypes, with means (SDs) of −0.41 (0.78) vs. 0.67 (0.90) (χ2 = 7.256; df = 1′ P = 0.007), respectively. Both sleep deprivation of at least 2 h/day (B = −0.96, 95% confidence interval (CI) = −1.86 to −0.11)) and the ∆-S100-B protein (−0.03, 95% CI = −0.06 to −0.02) were negatively correlated with the ∆-CPM-task, while the ∆-BDNF was positively correlated with the ∆-CPM-task (0.015, 95% CI = 0.01 to 0.03). We observed a difference in the ∆-CPT between PER34/4 and PER35/5 (0.11 (4.51) vs. 4.00 (2.60), respectively) (χ2 = 22.251; df = 1 P = 0.001). These findings suggest that the polymorphism of PER35/5 is associated with a decrease in the inhibitory function of the DPMS over the course of the day. However, sleep deprivation is an independent factor that also reduces the inhibitory function of the DPMS, regardless of the PER3 VNTR polymorphism.
A proteomic analysis of the statocyst endolymph in common cuttlefish (Sepia officinalis): an assessment of acoustic trauma after exposure to sound
Authors: Solé M. , Monge M. , André M. , Quero C.
Published: June 2019

Recent studies, both in laboratory and sea conditions, have demonstrated damage after sound exposure in the cephalopod statocyst sensory epithelium, which secretes endolymph protein. Here, the proteomic analysis of the endolymph was performed before and after sound exposure to assess the effects of exposure to low intensity, low frequency sounds on the statocyst endolymph of the Mediterranean common cuttlefish (Sepia officinalis), determining changes in the protein composition of the statocyst endolymph immediately and 24 h after sound exposure. Significant differences in protein expression were observed, especially 24 h after exposure. A total of 37 spots were significantly different in exposed specimens, 17 of which were mostly related to stress and cytoskeletal structure. Among the stress proteins eight spots corresponding to eight hemocyanin isoforms were under-expressed possible due to lower oxygen consumption. In addition, cytoskeletal proteins such as tubulin alpha chain and intermediate filament protein were also down-regulated after exposure. Thus, endolymph analysis in the context of acoustic stress allowed us to establish the effects at the proteome level and identify the proteins that are particularly sensitive to this type of trauma.
Coupling of Redox and Structural States in Cytochrome P450 Reductase Studied by Molecular Dynamics Simulation
Authors: Iijima Mikuru , Ohnuki Jun , Sato Takato , Sugishima Masakazu , Takano Mitsunori
Published: June 2019

Cytochrome P450 reductase (CPR) is the key protein that regulates the electron transfer from NADPH to various heme-containing monooxygenases. CPR has two flavin-containing domains: one with flavin adenine dinucleotide (FAD), called FAD domain, and the other with flavin mononucleotide (FMN), called FMN domain. It is considered that the electron transfer occurs via FAD and FMN (NADPH → FAD → FMN → monooxygenase) and is regulated by an interdomain open-close motion. It is generally thought that the structural state is coupled with the redox state, which, however, has not yet been firmly established. In this report, we studied the coupling of the redox and the structural states by full-scale molecular dynamics (MD) simulation of CPR (total 86.4 μs). Our MD result showed that while CPR predominantly adopts the closed state both in the oxidized and reduced states, it exhibits a tendency to open in the reduced state. We also found a correlation between the FAD-FMN distance and the predicted FMN-monooxygenase distance, which is embedded in the equilibrium thermal fluctuation of CPR. Based on these results, a physical mechanism for the electron transfer by CPR is discussed.
Enrichment of intestinal Lactobacillus by enhanced secretory IgA coating alters glucose homeostasis in P2rx7−/− mice
Authors: Perruzza Lisa , Strati Francesco , Gargari Giorgio , D’Erchia Anna Maria , Fosso Bruno , Pesole Graziano , Guglielmetti Simone , Grassi Fabio
Published: June 2019

The secretory immunoglobulin A (SIgA) in mammalian gut protects the organism from infections and contributes to host physiology by shaping microbiota composition. The mechanisms regulating the adaptive SIgA response towards gut microbes are poorly defined. Deletion of P2rx7, encoding for the ATP-gated ionotropic P2X7 receptor, leads to T follicular helper (Tfh) cells expansion in the Peyer’s patches (PPs) of the small intestine, enhanced germinal centre (GC) reaction and IgA secretion; the resulting alterations of the gut microbiota in turn affects host metabolism. Here, we define gut microbiota modifications that correlate with deregulated SIgA secretion and metabolic alterations in P2rx7−/− mice. In particular, Lactobacillus shows enhanced SIgA coating in P2rx7−/− with respect to wild-type (WT) mice. The abundance of SIgA-coated lactobacilli positively correlates with Tfh cells number and body weight, suggesting Lactobacillus-specific SIgA response conditions host metabolism. Accordingly, oral administration of intestinal Lactobacillus isolates from P2rx7−/− mice to WT animals results in altered glucose homeostasis and fat deposition. Thus, enhanced SIgA production by P2X7 insufficiency promotes Lactobacillus colonization that interferes with systemic metabolic homeostasis. These data indicate that P2X7 receptor-mediated regulation of commensals coating by SIgA is important in tuning the selection of bacterial taxa, which condition host metabolism.
Lineage tracing analysis of cone photoreceptor associated cis-regulatory elements in the developing chicken retina
Authors: Schick Estie , McCaffery Sean D. , Keblish Erin E. , Thakurdin Cassandra , Emerson Mark M.
Published: June 2019

During vertebrate retinal development, transient populations of retinal progenitor cells with restricted cell fate choices are formed. One of these progenitor populations expresses the Thrb gene and can be identified by activity of the ThrbCRM1 cis-regulatory element. Short-term assays have concluded that these cells preferentially generate cone photoreceptors and horizontal cells, however developmental timing has precluded an extensive cell type characterization of their progeny. Here we describe the development and validation of a recombinase-based lineage tracing system for the chicken embryo to further characterize the lineage of these cells. The ThrbCRM1 element was found to preferentially form photoreceptors and horizontal cells, as well as a small number of retinal ganglion cells. The photoreceptor cell progeny are exclusively cone photoreceptors and not rod photoreceptors, confirming that ThrbCRM1 progenitor cells are restricted from the rod fate. In addition, specific subtypes of horizontal cells and retinal ganglion cells were overrepresented, suggesting that ThrbCRM1 progenitor cells are not only restricted for cell type, but for cell subtype as well.
Efficient Grafting of Cyclodextrin to Alginate and Performance of the Hydrogel for Release of Model Drug
Authors: Omtvedt Line Aa. , Dalheim Marianne Ø. , Nielsen Thorbjørn T. , Larsen Kim L. , Strand Berit L. , Aachmann Finn L.
Published: June 2019

Controlling the rate of release of molecules from a hydrogel is of high interest for various drug delivery systems and medical devices. A strategy to alter the release profiles of soluble and poorly soluble active ingredients from hydrogels can be to combine the hydrogel forming ability of alginate with the inclusion forming ability of cyclodextrins (CyD). Here, β-CyD was grafted to alginate in a three-step synthesis using periodate oxidation, reductive amination and copper(I)-catalyzed azide-alkyne cycloaddition. A grafting degree of 4.7% mol β-CyD/mol sugar residues was obtained. The grafting degree was controlled by varying the reaction parameters where the amount of linker used in reductive amination was especially influential. Ca-alginate gel beads grafted with β-CyD showed increased uptake of the model molecule methyl orange. Release experiments showed that the grafted material had a prolonged release of methyl orange and an increased total amount of released methyl orange. These results show that the β-CyD grafted alginate is still able to form a hydrogel while the grafted cyclodextrins retain their ability to form inclusion complex with methyl orange. Further testing should be done with this system to investigate capability for drug delivery applications.
Wnt signalling mediates miR-133a nuclear re-localization for the transcriptional control of Dnmt3b in cardiac cells
Authors: Di Mauro Vittoria , Crasto Silvia , Colombo Federico Simone , Di Pasquale Elisa , Catalucci Daniele
Published: June 2019

MiR-133a is a muscle-enriched miRNA, which plays a key role for proper skeletal and cardiac muscle function via regulation of transduction cascades, including the Wnt signalling. MiR-133a modulates its targets via canonical mRNA repression, a process that has been largely demonstrated to occur within the cytoplasm. However, recent evidence has shown that miRNAs play additional roles in other sub-cellular compartments, such as nuclei. Here, we show that miR-133a translocates to the nucleus of cardiac cells following inactivation of the canonical Wnt pathway. The nuclear miR-133a/AGO2 complex binds to a complementary miR-133a target site within the promoter of the de novo DNA methyltransferase 3B (Dnmt3b) gene, leading to its transcriptional repression, which is mediated by DNMT3B itself. Altogether, these data show an unconventional role of miR-133a that upon its relocalization to the nucleus is responsible for epigenetic repression of its target gene Dnmt3b via a DNMT3B self-regulatory negative feedback loop.
Gene expression and functional comparison between multipotential stromal cells from lateral and medial condyles of knee osteoarthritis patients
Authors: Sanjurjo-Rodriguez Clara , Baboolal Thomas G. , Burska Agata N. , Ponchel Frederique , El-Jawhari Jehan J. , Pandit Hemant , McGonagle Dennis , Jones Elena
Published: June 2019

Osteoarthritis (OA) is the most common degenerative joint disorder. Multipotential stromal cells (MSCs) have a crucial role in joint repair, but how OA severity affects their characteristics remains unknown. Knee OA provides a good model to study this, as osteochondral damage is commonly more severe in the medial weight-bearing compartment compared to lateral side of the joint. This study utilised in vitro functional assays, cell sorting, gene expression and immunohistochemistry to compare MSCs from medial and lateral OA femoral condyles. Despite greater cartilage loss and bone sclerosis in medial condyles, there was no significant differences in MSC numbers, growth rates or surface phenotype. Culture-expanded and freshly-purified medial-condyle MSCs expressed higher levels of several ossification-related genes. Using CD271-staining to identify MSCs, their presence and co-localisation with TRAP-positive chondroclasts was noted in the vascular channels breaching the osteochondral junction in lateral condyles. In medial condyles, MSCs were additionally found in small cavities within the sclerotic plate. These data indicate subchondral MSCs may be involved in OA progression by participating in cartilage destruction, calcification and sclerotic plate formation and that they remain abundant in severe disease. Biological or biomechanical modulation of these MSCs may be a new strategy towards cartilage and bone restoration in knee OA.
Interplay of Darwinian Selection, Lamarckian Induction and Microvesicle Transfer on Drug Resistance in Cancer
Authors: Álvarez-Arenas Arturo , Podolski-Renic Ana , Belmonte-Beitia Juan , Pesic Milica , Calvo Gabriel F.
Published: June 2019

Development of drug resistance in cancer has major implications for patients’ outcome. It is related to processes involved in the decrease of drug efficacy, which are strongly influenced by intratumor heterogeneity and changes in the microenvironment. Heterogeneity arises, to a large extent, from genetic mutations analogously to Darwinian evolution, when selection of tumor cells results from the adaptation to the microenvironment, but could also emerge as a consequence of epigenetic mutations driven by stochastic events. An important exogenous source of alterations is the action of chemotherapeutic agents, which not only affects the signalling pathways but also the interactions among cells. In this work we provide experimental evidence from in vitro assays and put forward a mathematical kinetic transport model to describe the dynamics displayed by a system of non-small-cell lung carcinoma cells (NCI-H460) which, depending on the effect of a chemotherapeutic agent (doxorubicin), exhibits a complex interplay between Darwinian selection, Lamarckian induction and the nonlocal transfer of extracellular microvesicles. The role played by all of these processes to multidrug resistance in cancer is elucidated and quantified.
Sustainable Batch or Continuous-flow Preparation of Biomass-derived Fuels Using Sulfonated Organic Polymers
Authors: Trombettoni Valeria , Campana Filippo , Marrocchi Assunta , Vaccaro Luigi
Published: June 2019

The interest in biodiesel as an alternative fuel is ever increasing due to recent legislation requiring fuel manufacturers to add a set percentage of biofuel in their products. The present EU's biofuel policy introduces a blending target involving reaching a mandatory 6% reduction in the greenhouse gas intensity of fuels by 2020. Thus, biodiesel production that is sustainable in terms of feedstock, as well as of employment of clean, safe, and efficient manufacturing processes, is becoming urgent. In the past decade, many industrial processes have shifted toward the use of solid acid catalysts as a ‘green tool’ to replace traditional catalytic systems to efficiently produce biodiesel from low-cost biomass feedstock, i.e., resources with high free fatty acid content. Heterogeneous systems, indeed, enable their easy separation and recovery, recycling and reuse, possibly leading to waste-minimized protocols. Moreover, there is an ever-growing interest in exploiting the synergy between heterogeneous catalysis and continuous flow technology as a viable integrated sustainable solution to process intensification. In this chapter, we focus on the recent advances in the use of tuneable and versatile organic polymer-supported solid acid catalysts to produce biodiesel fuel in batch and in continuous mode. We restrict the discussion to the most widely employed members of this class, i.e., cation-exchange resins. Trends are identified between physico-chemical and morphological properties of the catalysts and their performance, while their recyclability aspects are also examined. Finally, a survey and brief discussion on these catalysts' performance in batch and continuous flow production of levulinates – biofuel additives structurally related to biodiesel – are also provided.
Mechanochemical Synthesis of Biologically Relevant Heterocycles
Authors: Leonardi Marco , Villacampa Mercedes , Menéndez J. Carlos
Published: June 2019

Mechanochemistry involves the application of mechanical energy to achieve chemical transformations. Since it is usually performed in solid state at room temperature, mechanochemistry is regarded as one of the pathways toward more sustainable synthetic chemistry. Furthermore, by working under solvent-free conditions, reagents are highly concentrated and solvation phenomena are not relevant, and the combination of these two factors often leads to accelerated reactions. This chapter provides an overview of the application of mechanochemical conditions to the synthesis of heterocycles, the compounds with the highest relevance for the pharmaceutical and agrochemical industries.
Polymer nanoparticles integrated with ESIPT modules for sensing cysteine based on modulation of their tautomeric emission
Authors: Zou Wu , Wang Qinge , Gong Fuchun , Kuang Yinjie , Xia Jiaoyun , Cao Zhong
Published: June 2019

Excited-state intramolecular proton transfer (ESIPT)-exhibiting polymer nanoparticles (e-PNPs) were prepared using 2,6-diformyl-4-methylphenol and guanidine hydrochloride.
Click chemistry as a route to the synthesis of structurally new and magnetically interesting coordination clusters: a {NiII8} complex with a trapezoidal prismatic topology
Authors: Abbasi Parisa , Athanasopoulou Angeliki A. , Mazarakioti Eleni C. , Gagnon Kevin J. , Teat Simon J. , Escuer Albert , Pilkington Melanie , Stamatatos Theocharis C.
Published: June 2019

A {Ni8} cluster with trapezoidal prismatic topology was prepared via the click reaction between MeCN and N3− ions.
Effects of ozone and produced hydroxyl radicals on the transformation of graphene oxide in aqueous media
Authors: Du Tingting , Adeleye Adeyemi S. , Zhang Tong , Yang Nan , Hao Rongjie , Li Yao , Song Weihua , Chen Wei
Published: June 2019

The hydroxyl radicals and ozone play different roles in ozonation of GO.
Exploration of [2 + 2 + 2] cyclotrimerisation methodology to prepare tetrahydroisoquinoline-based compounds with potential aldo–keto reductase 1C3 target affinity
Authors: Santos Ana R. N. , Sheldrake Helen M. , Ibrahim Ali I. M. , Danta Chhanda Charan , Bonanni Davide , Daga Martina , Oliaro-Bosso Simonetta , Boschi Donatella , Lolli Marco L. , Pors Klaus
Published: June 2019

Tetrahydroisoquinoline (THIQ) is a key structural component in many biologically active molecules including natural products and synthetic pharmaceuticals.
Fabrication of a counter electrode for dye-sensitized solar cells (DSSCs) using a carbon material produced with the organic ligand 2-methyl-8-hydroxyquinolinol (Mq)
Authors: Kumar Rahul , Sahajwalla Veena , Bhargava Parag
Published: June 2019

DSSCs fabricated using a carbon material showed a Jsc, Voc, and η of 11.00 mA cm−2, 0.75 V, and 4.25% respectively.
Horizons Community Board collection – emerging 2D materials for energy and electronics applications
Authors: Li Li , Ma Tianyi , Zhang Nan
Published: June 2019

A themed collection on emerging 2D materials for energy and electronics applications, guest edited by Nanoscale Horizons Community Board member Li Li, and Materials Horizons Community Board members Tianyi Ma and Nan Zhang.
Negative differential thermal resistance through nanoscale solid–fluid–solid sandwiched structures
Authors: Li Fan , Wang Jun , Xia Guodong , Li Zhigang
Published: June 2019

In this work, we propose a negative differential thermal resistance (NDTR) system using a nanoscale sandwiched fluid.
Gold doping of tin clusters: exo-vs.endohedral complexes
Authors: Gleditzsch Martin , Pašteka Lukáš F. , Götz Daniel A. , Shayeghi Armin , Johnston Roy L. , Schäfer Rolf
Published: June 2019

We present molecular beam electric deflection experiments on neutral gold-doped tin clusters. The combined experimental and theoretical analysis confirms that at least nine tin atoms are necessary to form a cage that is capable of encapsulating a gold atom.
Interfacial synthesis of micro-cuboid Ni0.55Co0.45C2O4 solid solution with enhanced electrochemical performance for hybrid supercapacitors
Authors: Wang Lin , Zhang Runa , Jiang Yang , Tian Hua , Tan Yu , Zhu Kaixin , Yu Zhifeng , Li Wang
Published: June 2019

The rare crystal nucleus for the growth of Ni0.55Co0.45C2O4 solid solution during a biphasic interfacial reaction contribute to the formation of the hierarchical micro-cuboid structure with excellent electrochemical performance.
Recent advances in catalytic asymmetric intermolecular oxidation of alkynes
Authors: Shen Wen-Bo , Tang Xiang-Ting
Published: June 2019

In recent years, gold-metal-catalyzed intermolecular alkyne oxidation by an N-oxide oxidant, which presumably involves a gold carbenoid intermediate, has attracted increasing attention because it circumvents the employment of hazardous and potentially explosive diazocarbonyl compounds as starting materials for carbene generation.
Identification of HSP90 as a direct target of artemisinin for its anti-inflammatory activity via quantitative chemical proteomics
Authors: Wu Guolin , Cheng Bao , Qian Hui , Ma Shengming , Chen Qin
Published: June 2019

Global profiling of the target proteins of ART for its anti-inflammatory activity via ABPP combined with quantitative chemical proteomics.
Hantzsch esters: an emerging versatile class of reagents in photoredox catalyzed organic synthesis
Authors: Wang Peng-Zi , Chen Jia-Rong , Xiao Wen-Jing
Published: June 2019

This minireview highlights the recent advances in the chemistry of Hantzsch esters in photoredox catalyzed organic synthesis, with particular emphasis placed on reaction mechanisms.
Modelling the formation of porous organic gels – how structural properties depend on growth conditions
Authors: Prostredny Martin , Fletcher Ashleigh , Mulheran Paul
Published: June 2019

We explore how structural properties depend on the growth conditions in a model of gel nucleation, growth and aggregation.
Influence of l-arginine on performances of polyamide thin-film composite reverse osmosis membranes
Authors: Chen Dandan , Chen Qiang , Liu Tianyu , Kang Jian , Xu Ruizhang , Cao Ya , Xiang Ming
Published: June 2019

l-Arginine (Arg) as an aqueous additive was incorporated into the polyamide selective layer during interfacial polymerization, thereby the separation performance and anti-fouling properties of the resulting RO membranes were enhanced.
Fluorescence sensing of tyrosinase activity based on amine rich carbon dots through direct interaction in a homogeneous system: detection mechanism and application
Authors: Zhang Jianzhong , Chen Yuyuan , Zheng Zongfu , Wang Zhenzhen , Zheng Yanjie , Lin Xinhua , Weng Shaohuang
Published: June 2019

As a vital, copper-containing oxidase, tyrosinase (TYR) is useful as a biomarker for the screening of skin diseases.
Fabrication of Tween-20 coated PVDF membranes for wastewater treatment: optimization of preparation parameters, removal and membrane fouling control performance
Authors: Wu Daoji , Zhou Weiwei , Cheng Xiaoxiang , Luo Congwei , Li Peijie , Zhang Fengzhi , Ren Zixiao
Published: June 2019

In the present study, polyoxyethylene (20) sorbitan monolaurate (Tween-20) was employed as a surface coating agent for hydrophilic modification of poly(vinylidene fluoride) microfiltration membranes.
Total synthesis of griseusins and elucidation of the griseusin mechanism of action
Authors: Zhang Yinan , Ye Qing , Ponomareva Larissa V. , Cao Yanan , Liu Yang , Cui Zheng , Van Lanen Steven G. , Voss S. Randal , She Qing-Bai , Thorson Jon S.
Published: June 2019

An efficient divergent synthesis of griseusins enabled SAR studies, mechanistic elucidation and evaluation in an axolotl tail regeneration model.
Thymine DNA glycosylase recognizes the geometry alteration of minor grooves induced by 5-formylcytosine and 5-carboxylcytosine
Authors: Fu Tianran , Liu Liping , Yang Qing-Lin , Wang Yuxin , Xu Pan , Zhang Lin , Liu Shien , Dai Qing , Ji Quanjiang , Xu Guo-Liang , He Chuan , Luo Cheng , Zhang Liang
Published: June 2019

Thymine DNA glycosylase (TDG) recognizes the geometry alteration of DNA minor grooves induced by 5-formylcytosine (5fC) in DNA demethylation pathways.
Dynamics near planar walls for various model self-phoretic particles
Authors: Bayati Parvin , Popescu Mihail N. , Uspal William E. , Dietrich S. , Najafi Ali
Published: June 2019

Dynamics of chemically active particles moving by self-phoresis near chemically inert walls is studied theoretically by employing various choices for the activity function.
Healable and shape editable supercapacitors based on shape memory polyurethanes
Authors: Li Tianqi , Fang Xu , Pang Qiang , Huang Weimin , Sun Junqi
Published: June 2019

Healable and shape-editable supercapacitors can heal damage and be shape-edited to desired geometries with a negligible decay in the specific capacitance.
Cu supported on polymeric carbon nitride for selective CO2 reduction into CH4: a combined kinetics and thermodynamics investigation
Authors: Li Jieyuan , Yan Ping , Li Kanglu , You Junjie , Wang Hong , Cui Wen , Cen Wanglai , Chu Yinghao , Dong Fan
Published: June 2019

Metal-based cocatalysts have been widely applied in the photocatalytic CO2 reduction reaction (CO2RR) and the integration of cocatalysts/semiconductors is expected to enhance the selectivity of the catalytic reaction.
Immunostimulant and biocompatible gold and silver nanoparticles synthesized using the Ulva intestinalis L. aqueous extract
Authors: González-Ballesteros N. , Diego-González L. , Lastra-Valdor M. , Rodríguez-Argüelles M. C. , Grimaldi M. , Cavazza A. , Bigi F. , Simón-Vázquez R.
Published: June 2019

The biocompatibility properties of gold and silver nanoparticles synthesized by green chemistry.
Self-assembly of mitochondria-specific peptide amphiphiles amplifying lung cancer cell death through targeting the VDAC1–hexokinase-II complex
Authors: Liu Dan , Angelova Angelina , Liu Jianwen , Garamus Vasil M. , Angelov Borislav , Zhang Xinlei , Li Yawen , Feger Guillaume , Li Na , Zou Aihua
Published: June 2019

Novel cell-penetrating peptides self-assemble into ellipsoid-shape nanostructures which amplified the apoptotic stimuli by weakening the VDAC1–HK-II interaction.
Thermally activated delayed fluorescence emitters with low concentration sensitivity for highly efficient organic light emitting devices
Authors: Fan Xiao-Chun , Wang Kai , Zheng Cai-Jun , Dai Gao-Le , Shi Yi-Zhong , Li Yan-Qing , Yu Jia , Ou Xue-Mei , Zhang Xiao-Hong
Published: June 2019

By introducing a fluorene group, the molecular rigidity and intermolecular steric hindrance of SPFS-PXZ are greatly improved. As a result, SPFS-PXZ successfully realizes high external quantum efficiencies with low concentration sensitivity in OLEDs.
Bias and molecular-length dependent odd–even effect of rectification in 4′-methyl-2,2′-bipyridyl-terminated n-alkanethiolate single-molecule diodes
Authors: Wei Ming-Zhi , Fu Xiao-Xiao , Wang Zi-Qun , Hu Gui-Chao , Li Zong-Liang , Wang Chuan-Kui , Zhang Guang-Ping
Published: June 2019

The odd–even effect in the rectification of SCnBIPY diodes reverses with the increase of the bias voltage or the length of the alkyl chain.
Experimental investigation of quantum interference in charge transport through molecular architectures
Authors: Li Xiaohui , Tan Zhibing , Huang Xiaojuan , Bai Jie , Liu Junyang , Hong Wenjing
Published: June 2019

We summarized the experimental investigation of quantum interference in charge transport through various molecular architectures at single-molecule scale.
Thermal behaviour analysis in a porcelain‐housed ZnO surge arrester by computer simulations and thermography
Authors: Andrade Arthur F. , Costa Edson G. , Fernandes Josué M.B. , Alves Helem M.M. , Amorim Filho Cícero R.C.
Published: June 2019

In this article, an analysis of heat transfer in a porcelain‐housed ZnO surge arrester is presented. Due to the fact that ZnO‐based surge arresters are key components for protection and reliability of electrical systems, it is necessary to seek techniques to assure correct assessment. In porcelain‐housed arresters, the air gap leads to an increased thermal resistance between the ambient and the varistor column. Consequently, a thermal analysis must consider convection and radiation heat transfer mechanisms, besides heat conduction. This study proposes the use of computational simulations in combination with thermography as a tool for a temperature‐based estimation of the varistor state. For the analysis, temperature rise tests were performed in a 69‐kV ceramic‐housed arrester to measure material emissivity and produce data to fit the simulated response. Furthermore, the thermal response of the surge arresters subject to an impulsive energy input was evaluated. The simulations allow to relate varistors temperature and housing temperature with regard to a specified amount of dissipated power. The obtained results show that the used technique can be an effective method for arrester monitoring and may allow to define assessing criteria for a porcelain‐housed arrester based on housing temperature measurements.
Mice flow aggregation approach for Green networking
Authors: Lin Qin‐Liang , Yu Shun‐Zheng
Published: June 2019

Studies have shown that most of the flows in data centres are mice flows and last short time. However, existing green networking solutions do not consider this traffic characteristic. A mass of mice flows may be rerouted after network equipment is put into sleep mode and this can result in significant degradation of network performance. In this study, the authors propose a novel solution for green networking called energy‐efficient flow scheduling approach (EFSA). EFSA aggregates mice flow into a minimal set of links, and the largest flows that result in an overload of links in the set are rerouted in time. Instead of managing every mice flows, only a few numbers of largest flows are rerouted. Unused switches/links will be put into sleep mode for energy saving. The evaluation of EFSA shows that it can significantly reduce the number of rerouted flows and improve the performance of data centre networks while saving network energy efficiently.
Outage and delay performance of content caching in two‐tier cooperative cellular networks
Authors: Rostami Ghadi Farshad , Javan Mohammad Reza
Published: June 2019

The authors consider a content‐centric two‐tier heterogeneous cellular network where the macro base stations (MBSs) and small base stations (SBSs) are spread based on two independent Poisson point processes. The set of contents are stored in the MBSs while a subset of the contents which are the most popular are cached in the SBSs. We assume that there is no direct link between the MBSs and the users, and users send their content requests to their nearest SBS. If the SBS has not the requested content, the nearest MBS to the serving SBS serves the user through that SBS. Furthermore, the authors incorporated the automatic repeat request (ARQ)‐based transmission with a fixed number of the ARQ rounds, and analyse the delay experienced by users. The authors obtained closed‐form expressions for the average outage probability and the average delay in case of successful ARQ transmission. It is shown that the content distribution based on popularity decreases the average outage probability and average delay. Also, it is shown that the transmission from MBS to the user through SBS improves the performance in terms of average outage probability and average delay. Finally, using simulations the authors study the proposed schemes for different network parameters.
Subarray hybrid precoding with finite‐resolution PSs for massive MIMO capacity maximisation
Authors: Alarfaj Mohammed , Liu Huaping
Published: June 2019

The addition of analogue processing to the digital precoding, known as hybrid beamforming (HB), is an efficient solution for massive multiple‐input multiple‐output (MIMO) systems. The design of a phase shifter (PS) network plays an important role in the complete precoder operation because it necessitates accurate components for realising precise phases, and that can be costly. Finite resolution PSs are good alternatives because they need simpler hardware implementation than those with infinite resolution. However, the degradation of performance of a MIMO system with very low‐resolution PSs is significant. Although recent studies suggest adding extra radio frequency (RF) chains to substitute for the accuracy of the PSs, it is complex, expensive and not energy efficient. This study demonstrates that HB with low‐resolution PSs can realise a high performance without increasing the number of RF chains. The authors proposed solution relies on a proper selection of the weights of the RF beamformer, hence exploiting the structure of the multipath propagation channel to maximise the system capacity. They also show that separating antennas from each other by sufficient distance, results in a less correlated channel, and thus, a minimal loss in the capacity and the antenna gains are assured.
Lightweight energy‐efficient framework for sensor real‐time communications
Authors: Mohamed Marwa F. , Ahmed Mohamed Ali , Nassar Hamed
Published: June 2019

Sensor node communications are usually the most energy consuming among its activities. Therefore, reducing those communications necessarily preserves the node limited energy. One successful approach to this end is to reduce both the number of transmissions made by the node and the payload of each transmission. Numerous proposals have recently been made to achieve this reduction by approximating the node data at the sink via forecasting. However, many of these proposals are plagued with one or more of three problems: intensive computations, excessive delays and backtracking. In this study, the authors introduce the lightweight energy‐efficient real‐time (LEERT) framework, which avoids all three problems while saving considerably on energy consumption. The savings are achieved by both reducing immensely the number of transmissions and reducing the payload of each transmission to only one element. This is actually the minimum any framework would hope for. LEERT is also extremely light, performing only four primitive operations per measurement on average. Its storage requirements are even lighter – only one past measurement needs to be retained in memory. LEERT has passed extensive validation tests using real‐world data. Its performance has been evaluated against two recent energy‐efficient frameworks and found to have an astounding edge.
Fast computation of electric field and capacitance matrix of transformer windings with boundary element method and adaptive cross approximation
Authors: Drandić Ana , Trkulja Bojan
Published: June 2019

Accurate and fast computation of electric fields is of great interest in transformer design. This article presents a fast and precise method of computation of electric field of transformer windings based on the boundary element method and integral equations approach. Additionally, computation of the capacitance matrix of a transformer geometry is presented. Proposed methodology depends on the knowledge of the transformer geometry. Improvement in computational costs and memory requirements of the developed electrostatic solver is achieved by implementation of the adaptive cross approximation algorithm. Results are benchmarked against commercial software based on the finite element method and applicability of the developed solver is proven.
Accurate identification and characterisation of transient phenomena using wavelet transform and mathematical morphology
Authors: Guillén‐García Emmanuel , Morales‐Velazquez Luis , Zorita‐Lamadrid Angel Luis , Duque‐Perez Oscar , Osornio‐Rios Roque Alfredo , Romero‐Troncoso Rene de Jesus
Published: June 2019

Electric transient events are recurrent phenomena in electrical installations and distribution systems or grids; hence, the identification of these kinds of phenomena has become an important topic for researchers. This work presents a methodology to identify and accurately delimit transients in current signals of non‐residential buildings. The proposed method firstly analyses the signal using the wavelet transform to pre‐visualise the transients, and then opening and closing morphological operators are applied to the signal to find the beginning and ending of the transient; furthermore, the highest point of the transient and its location is obtained. The experimentation is performed with real current signals measured in a non‐residential building. The results indicate that the proposed method can precisely identify and delimit transients, even when the transients are very close to each other.
Combined heat and power dynamic economic dispatch with demand side management incorporating renewable energy sources and pumped hydro energy storage
Authors: Basu Mousumi
Published: June 2019

This study suggests chaotic fast convergence evolutionary programming (CFCEP) rooted in Tent equation for solving intricate actual world combined heat and power dynamic economic dispatch (CHPDED) problem with demand side management (DSM) incorporating renewable energy sources and pumped‐storage‐hydraulic unit. The valve point effect and proscribed workable area of thermal generators and solar and wind power uncertainty have been pondered. DSM programmes decrease cost and boost up power system security. To investigate the upshot of DSM, the CHPDED problem is solved with and without DSM. In the recommended CFCEP technique, chaotic sequences have been pertained for acquiring the dynamic scaling factor setting in fast convergence evolutionary programming (FCEP). Introduction of chaotic sequences helps FCEP to avoid premature convergence. The efficiency of the recommended technique is revealed in a test system. Simulation outcomes of the recommended technique have been evaluated with those attained by FCEP and differential evolution. It has been examined from the assessment that the recommended CFCEP has the capability to bestow with a better‐quality solution.
Performance analysis of a solar‐powered water pumping using improved SIDO buck–boost converter
Authors: Singh Bhim , Mishra Anjanee Kumar
Published: June 2019

This study proposes a low‐cost solar‐powered water pumping system (SPWPS) utilising a proposed single‐input dual‐output (SIDO) buck–boost converter with an efficient control technique for the switched reluctance motor (SRM) drive. The newly designed buck–boost converter provides a continuous input and output current to the motor with a low ripple content. This converter is also capable to minimise the size of DC‐link capacitor and to provide a balanced dual output voltage supply. Owing to the fundamental frequency switching of a split DC mid‐point converter, there is a considerable reduction in the semiconductor losses and provides an opportunity to eliminate the sensors from the motor side. In addition, an improved perturb and observe (P&O) maximum power point tracking (MPPT) technique is also implemented in proposed system. The implemented MPPT algorithm has drift‐free operation and an ability to control the pumping rate also at maximum PV power generation, which is usually difficult in standalone water pumping system. Test results are presented on an 875‐Wp PV array fed a 1 hp pump to demonstrate sound agreement between the simulated and test results of proposed system.
Open‐loop transfer functions of buck–boost converter by circuit‐averaging technique
Authors: Saini Dalvir Kaur , Kazimierczuk Marian Kazimierz
Published: June 2019

This study shows the derivation of the power‐stage transfer functions and input and output impedances of a buck–boost pulse width‐modulated (PWM) dc–dc converter operating in continuous‐conduction mode. The expressions are derived using the small‐signal model obtained by the circuit‐averaging technique. Using the small‐signal dynamic model, both transient and frequency domain characteristics are determined. An example buck–boost converter with the following specifications was considered: supply voltage 12 V, output voltage 5 V, switching frequency 200 kHz, and output power 10 W. The modification of the power‐stage transfer function to include the time delay between the MOSFET gate drive and the duty cycle is considered and is modelled by the first‐order Padè approximation. The theoretical predictions were verified by experiments and excellent agreement between the results was observed.
Battery model based on cubic over‐potential differential equation
Authors: Hsieh Yao‐Ching , Chiu Yu‐Chun , Wu Wei‐Ting , Huang You‐Chun
Published: June 2019

This study is research upon the over‐potential of Li‐iron batteries. By performing many cycles of charging–discharging experiments under controlled ambient temperature, adjusted depth‐of‐discharge, and discharging current rates, the dynamic voltage variation data is collected. A model based on the cubic over‐potential differential equation is proposed. This model is able to predict the gradually prolonged time‐constant dynamics of the battery loaded voltages with fewer parameters. By this way, a set of procedures is also proposed to adjust the parameters as the battery ages. The experimental result is used to verify the feasibility of this model. Even for the aged batteries, the prediction error is small and the result is satisfactory.
High step‐up DC–DC converter with reduced voltage and current stress of elements
Authors: Majarshin Alireza Razavi , Babaei Ebrahim
Published: June 2019

In this study, a high step‐up and high output voltage unidirectional DC–DC converter is proposed. This converter is based on coupled inductor structures and has several integral advantages as follows. The output of the proposed converter is stacked which results in high voltage gain, low voltage stress of output‐side components and also, high voltage loads. Metal‐oxide field effect transistors with low on‐state resistance can be used. In the meantime, the input side of the converter acts like an interleaved structure, so the current stress of the elements is reduced and higher power application is available. In addition, there is no limitation for normal duty‐cycle of switches. After introducing and analysing of the proposed converter, laboratory results are presented to validate the claims.
Three‐phase bi‐directional wireless EV charging system with high tolerance to pad misalignment
Authors: Song Yuan , Madawala Udaya K. , Thrimawithana Duleepa J. , Vilathgamuwa Mahinda
Published: June 2019

Electric vehicles (EVs), which are becoming increasingly popular, can be charged by either wired or wireless means. The latter, based on wireless power transfer (WPT) technology, is convenient and safe, but pad misalignment is one of the major concerns as it causes a reduction in charging power level, prolonging the charging process. Therefore, wireless charging systems with high tolerance to pad misalignment are necessary. This study proposes a three‐phase bi‐directional wireless power transfer (BD‐WPT) system with a control scheme that offers high tolerance to pad misalignment in EV charging applications. The system uses simple coil designs for pads and utilises the magnetic coupling among pads to compensate for the power variation. A comprehensive mathematical model, incorporating all magnetic cross‐coupling effects, is presented to investigate the charging performance of the system under pad misalignment and different pad spacings. To demonstrate the validity of the proposed system, theoretical and simulated results are presented, benchmarking against a single phase WPT system, and in comparison to a prototype 1.3 kW three‐phase BD‐WPT system. Results are convincing and indicate that the proposed three‐phase BD‐WPT system with small pad spacing is more tolerant to wide pad misalignment in EV charging applications.
Rao‐Blackwellised particle filtering for low‐cost encoder/INS/GNSS integrated vehicle navigation with wheel slipping
Authors: Zhou Haoyu , Yao Zheng , Fan Caoming , Wang Shengli , Lu Mingquan
Published: June 2019

This study presents a Rao‐Blackwellised particle filter (RBPF)‐based encoder/inertial navigation system (INS)/global navigation satellite system (GNSS) integration method for improving the navigation performance of an autonomous land vehicle (ALV) with wheel slipping. In contrast to traditional integration methods, the proposed integration method introduces an overall wheel slip consideration for the ALV, which greatly improves the accuracy of the velocity estimation, especially when the inertial sensor is low cost. Additionally, the proposed integrated system uses double‐difference pseudorange measurements instead of single point positioning results provided by low‐cost GNSS receivers, which greatly improves the accuracy of the position estimation. To verify the navigation performance of the proposed integrated system, comparisons between the states estimated by the proposed system, the EKF‐based integrated system and the joint wheel‐slip and motion‐estimation system are provided. The results of the experiment show that the proposed integrated system has the highest accuracy in both the position estimation and the velocity estimation among the three compared systems, and can improve the navigation performance during GNSS signals outages.
Dual‐loop control strategy applied to the cluster of multiple nanogrids for rural electrification applications
Authors: Nasir Mashood , Anees Muhammad , Abbas Khan Hassan , Guerrero Josep M.
Published: June 2019

In this study, a dual‐loop control strategy is applied to a highly distributed architecture of photovoltaic/battery‐based DC microgrid built through an interconnection of a cluster of multiple nanogrids. Typically, in these distributed architectures, resource sharing among the spatially distributed nanogrids is enabled via communication‐based control methodologies, which adds cost and complexity to the overall system. Alternately, a communication‐less and decentralised control methodology is proposed which utilises inner loop current control and outer loop voltage droop (V–I droop) control for the coordinated resource sharing among the distributed resources. The proposed control scheme adapts various modes based on the local measurements of bus voltage and battery state of charge, therefore, offers a distributed solution, omitting the need for centralised communication control. Various scenarios of power sharing among the contributing nanogrids are evaluated through the proposed multi‐mode adaptive control. The efficacy of the proposed control scheme is validated through simulations on MATLAB/Simulink and laboratory scale hardware prototype. Results show that the proposed decentralised control strategy is capable to ensure stable and coordinated operation without any dedicated layer of communication among the dispersed generation/storage resources.
Biclustering‐based association rule mining approach for predicting cancer‐associated protein interactions
Authors: Dey Lopamudra , Mukhopadhyay Anirban
Published: June 2019

Protein–protein interactions (PPIs) have been widely used to understand different biological processes and cellular functions associated with several diseases like cancer. Although some cancer‐related protein interaction databases are available, lack of experimental data and conflicting PPI data among different available databases have slowed down the cancer research. Therefore, in this study, the authors have focused on various proteins that are directly related to different types of cancer disease. They have prepared a PPI database between cancer‐associated proteins with the rest of the human proteins. They have also incorporated the annotation type and direction of each interaction. Subsequently, a biclustering‐based association rule mining algorithm is applied to predict new interactions with type and direction. This study shows the prediction power of association rule mining algorithm over the traditional classifier model without choosing a negative data set. The time complexity of the biclustering‐based association rule mining is also analysed and compared to traditional association rule mining. The authors are able to discover 38 new PPIs which are not present in the cancer database. The biological relevance of these newly predicted interactions is analysed by published literature. Recognition of such interactions may accelerate a way of developing new drugs to prevent different cancer‐related diseases.