bluuebunny/crossref_metadata_2025 huggingface dataset:
Pathogenic ARH3 mutations result in ADP-ribose chromatin scars during DNA strand break repair
Authors: Hanzlikova Hana , Prokhorova Evgeniia , Krejcikova Katerina , Cihlarova Zuzana , Kalasova Ilona , Kubovciak Jan , Sachova Jana , Hailstone Richard , Brazina Jan , Ghosh Shereen , Cirak Sebahattin , Gleeson Joseph G. , Ahel Ivan , Caldecott Keith W.
Published: July 2020

Neurodegeneration is a common hallmark of individuals with hereditary defects in DNA single-strand break repair; a process regulated by poly(ADP-ribose) metabolism. Recently, mutations in the ARH3 (ADPRHL2) hydrolase that removes ADP-ribose from proteins have been associated with neurodegenerative disease. Here, we show that ARH3-mutated patient cells accumulate mono(ADP-ribose) scars on core histones that are a molecular memory of recently repaired DNA single-strand breaks. We demonstrate that the ADP-ribose chromatin scars result in reduced endogenous levels of important chromatin modifications such as H3K9 acetylation, and that ARH3 patient cells exhibit measurable levels of deregulated transcription. Moreover, we show that the mono(ADP-ribose) scars are lost from the chromatin of ARH3-defective cells in the prolonged presence of PARP inhibition, and concomitantly that chromatin acetylation is restored to normal. Collectively, these data indicate that ARH3 can act as an eraser of ADP-ribose chromatin scars at sites of PARP activity during DNA single-strand break repair.
Highly reversible oxygen redox in layered compounds enabled by surface polyanions
Authors: Chen Qing , Pei Yi , Chen Houwen , Song Yan , Zhen Liang , Xu Cheng-Yan , Xiao Penghao , Henkelman Graeme
Published: July 2020

Oxygen-anion redox in lithium-rich layered oxides can boost the capacity of lithium-ion battery cathodes. However, the over-oxidation of oxygen at highly charged states aggravates irreversible structure changes and deteriorates cycle performance. Here, we investigate the mechanism of surface degradation caused by oxygen oxidation and the kinetics of surface reconstruction. Considering Li2MnO3, we show through density functional theory calculations that a high energy orbital (lO2p’) at under-coordinated surface oxygen prefers over-oxidation over bulk oxygen, and that surface oxygen release is then kinetically favored during charging. We use a simple strategy of turning under-coordinated surface oxygen into polyanionic (SO4)2−, and show that these groups stabilize the surface of Li2MnO3 by depressing gas release and side reactions with the electrolyte. Experimental validation on Li1.2Ni0.2Mn0.6O2 shows that sulfur deposition enhances stability of the cathode with 99.0% capacity remaining (194 mA h g−1) after 100 cycles at 1 C. Our work reveals a promising surface treatment to address the instability of highly charged layered cathode materials.
Author Correction: Benthic fauna declined on a whitening Antarctic continental shelf
Authors: Pineda-Metz Santiago E. A. , Gerdes Dieter , Richter Claudio
Published: July 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
R-loop induced G-quadruplex in non-template promotes transcription by successive R-loop formation
Authors: Lee Chun-Ying , McNerney Christina , Ma Kevin , Zhao Walter , Wang Ashley , Myong Sua
Published: July 2020

G-quadruplex (G4) is a noncanonical secondary structure of DNA or RNA which can enhance or repress gene expression, yet the underlying molecular mechanism remains uncertain. Here we show that when positioned downstream of transcription start site, the orientation of potential G4 forming sequence (PQS), but not the sequence alters transcriptional output. Ensemble in vitro transcription assays indicate that PQS in the non-template increases mRNA production rate and yield. Using sequential single molecule detection stages, we demonstrate that while binding and initiation of T7 RNA polymerase is unchanged, the efficiency of elongation and the final mRNA output is higher when PQS is in the non-template. Strikingly, the enhanced elongation arises from the transcription-induced R-loop formation, which in turn generates G4 structure in the non-template. The G4 stabilized R-loop leads to increased transcription by a mechanism involving successive rounds of R-loop formation.
Cryo-EM structure of arabinosyltransferase EmbB from Mycobacterium smegmatis
Authors: Tan Yong Zi , Rodrigues José , Keener James E. , Zheng Ruixiang Blake , Brunton Richard , Kloss Brian , Giacometti Sabrina I. , Rosário Ana L. , Zhang Lei , Niederweis Michael , Clarke Oliver B. , Lowary Todd L. , Marty Michael T. , Archer Margarida , Potter Clinton S. , Carragher Bridget , Mancia Filippo
Published: July 2020

Arabinosyltransferase B (EmbB) belongs to a family of membrane-bound glycosyltransferases that build the lipidated polysaccharides of the mycobacterial cell envelope, and are targets of anti-tuberculosis drug ethambutol. We present the 3.3 Å resolution single-particle cryo-electron microscopy structure of Mycobacterium smegmatis EmbB, providing insights on substrate binding and reaction mechanism. Mutations that confer ethambutol resistance map mostly around the putative active site, suggesting this to be the location of drug binding.
In silico modelling of cancer nanomedicine, across scales and transport barriers
Authors: Stillman Namid R. , Kovacevic Marina , Balaz Igor , Hauert Sabine
Published: July 2020

Nanoparticles promise to improve the treatment of cancer through their increasingly sophisticated functionalisations and ability to accumulate in certain tumours. Yet recent work has shown that many nanomedicines fail during clinical trial. One issue is the lack of understanding of how nanoparticle designs impact their ability to overcome transport barriers in the body, including their circulation in the blood stream, extravasation into tumours, transport through tumour tissue, internalisation in the targeted cells, and release of their active cargo. Increased computational power, as well as improved multi-scale simulations of tumours, nanoparticles, and the biological transport barriers that affect them, now allow us to investigate the influence of a range of designs in biologically relevant scenarios. This presents a new opportunity for high-throughput, systematic, and integrated design pipelines powered by data and machine learning. With this paper, we review latest results in multi-scale simulations of nanoparticle transport barriers, as well as available software packages, with the aim of focussing the wider research community in building a common computational framework that can overcome some of the current obstacles facing efficient nanoparticle design.
Single-cell RNA sequencing reveals that lung mesenchymal progenitor cells in IPF exhibit pathological features early in their differentiation trajectory
Authors: Beisang Daniel J. , Smith Karen , Yang Libang , Benyumov Alexey , Gilbertsen Adam , Herrera Jeremy , Lock Eric , Racila Emilian , Forster Colleen , Sandri Brian J. , Henke Craig A. , Bitterman Peter B.
Published: July 2020

In Idiopathic Pulmonary Fibrosis (IPF), there is unrelenting scarring of the lung mediated by pathological mesenchymal progenitor cells (MPCs) that manifest autonomous fibrogenicity in xenograft models. To determine where along their differentiation trajectory IPF MPCs acquire fibrogenic properties, we analyzed the transcriptome of 335 MPCs isolated from the lungs of 3 control and 3 IPF patients at the single-cell level. Using transcriptional entropy as a metric for differentiated state, we found that the least differentiated IPF MPCs displayed the largest differences in their transcriptional profile compared to control MPCs. To validate entropy as a surrogate for differentiated state functionally, we identified increased CD44 as a characteristic of the most entropic IPF MPCs. Using FACS to stratify IPF MPCs based on CD44 expression, we determined that CD44hi IPF MPCs manifested an increased capacity for anchorage-independent colony formation compared to CD44lo IPF MPCs. To validate our analysis morphologically, we used two differentially expressed genes distinguishing IPF MPCs from control (CD44, cell surface; and MARCKS, intracellular). In IPF lung tissue, pathological MPCs resided in the highly cellular perimeter region of the fibroblastic focus. Our data support the concept that IPF fibroblasts acquire a cell-autonomous pathological phenotype early in their differentiation trajectory.
A novel humanized mouse model to study the function of human cutaneous memory T cells in vivo in human skin
Authors: Klicznik Maria M. , Benedetti Ariane , Gail Laura M. , Varkhande Suraj R. , Holly Raimund , Laimer Martin , Stoecklinger Angelika , Sir Andreas , Reitsamer Roland , Neuper Theresa , Horejs-Hoeck Jutta , Rosenblum Michael D. , Campbell Daniel J. , Murauer Eva M. , Gratz Iris K.
Published: July 2020

Human skin contains a population of memory T cells that supports tissue homeostasis and provides protective immunity. The study of human memory T cells is often restricted to in vitro studies and to human PBMC serving as primary cell source. Because the tissue environment impacts the phenotype and function of memory T cells, it is crucial to study these cells within their tissue. Here we utilized immunodeficient NOD-scid IL2rγnull (NSG) mice that carried in vivo-generated engineered human skin (ES). ES was generated from human keratinocytes and fibroblasts and was initially devoid of skin-resident immune cells. Upon adoptive transfer of human PBMC, this reductionist system allowed us to study human T cell recruitment from a circulating pool of T cells into non-inflamed human skin in vivo. Circulating human memory T cells preferentially infiltrated ES and showed diverse functional profiles of T cells found in fresh human skin. The chemokine and cytokine microenvironment of ES closely resembled that of non-inflamed human skin. Upon entering the ES T cells assumed a resident memory T cell-like phenotype in the absence of infection, and a proportion of these cutaneous T cells can be locally activated upon injection of monocyte derived dendritic cells (moDCs) that presented Candida albicans. Interestingly, we found that CD69+ memory T cells produced higher levels of effector cytokines in response to Candida albicans, compared to CD69- T cells. Overall, this model has broad utility in many areas of human skin immunology research, including the study of immune-mediated skin diseases.
Electroacupuncture intervention of visceral hypersensitivity is involved in PAR-2-activation and CGRP-release in the spinal cord
Authors: Shah Manoj K. , Ding Yi , Wan Juan , Janyaro Habibullah , Tahir Adnan Hassan , Vodyanoy Vitaly , Ding Ming-Xing
Published: July 2020

Electroacupuncture (EA) relieves visceral hypersensitivity (VH) with underlying inflammatory bowel diseases. However, the mechanism by which EA treats ileitis-induced VH is not clearly known. To assess the effects of EA on ileitis-induced VH and confirm whether EA attenuates VH through spinal PAR-2 activation and CGRP release, goats received an injection of 2,4,6-trinitro-benzenesulfonic-acid (TNBS) solution into the ileal wall. TNBS-injected goats were allocated into VH, Sham acupuncture (Sham-A) and EA groups, while goats treated with saline instead of TNBS solution were used as the control. Goats in EA group received EA at bilateral Hou-San-Li acupoints for 0.5 h at 7 days and thereafter repeated every 3 days for 6 times. Goats in the Sham-A group were inserted with needles for 0.5 h at the aforementioned acupoints without any hand manipulation and electric stimulation. Visceromotor responses to colorectal distension, an indicator of VH, were recorded by electromyography. The terminal ileum and thoracic spinal cord (T11) were sampled for evaluating ileitis at days 7 and 22, and distribution and expression-levels of PAR-2, CGRP and c-Fos on day 22. TNBS-treated-goats exhibited apparent transmural-ileitis on day 7, microscopically low-grade ileitis on day 22 and VH at days 7–22. Goats of Sham-A, VH or EA group showed higher (P < 0.01) VH at days 7–22 than the Control-goats. EA-treated goats exhibited lower (P < 0.01) VH as compared with Sham-A or VH group. Immunoreactive-cells and expression-levels of spinal PAR-2, CGRP and c-Fos in the EA group were greater (P < 0.01) than those in the Control group, but less (P < 0.01) than those in Sham-A and VH groups on day 22. Downregulation of spinal PAR-2 and CGRP levels by EA attenuates the ileitis and resultant VH.
A physics-based energy function allows the computational redesign of a PDZ domain
Authors: Opuu Vaitea , Sun Young Joo , Hou Titus , Panel Nicolas , Fuentes Ernesto J. , Simonson Thomas
Published: July 2020

Computational protein design (CPD) can address the inverse folding problem, exploring a large space of sequences and selecting ones predicted to fold. CPD was used previously to redesign several proteins, employing a knowledge-based energy function for both the folded and unfolded states. We show that a PDZ domain can be entirely redesigned using a “physics-based” energy for the folded state and a knowledge-based energy for the unfolded state. Thousands of sequences were generated by Monte Carlo simulation. Three were chosen for experimental testing, based on their low energies and several empirical criteria. All three could be overexpressed and had native-like circular dichroism spectra and 1D-NMR spectra typical of folded structures. Two had upshifted thermal denaturation curves when a peptide ligand was present, indicating binding and suggesting folding to a correct, PDZ structure. Evidently, the physical principles that govern folded proteins, with a dash of empirical post-filtering, can allow successful whole-protein redesign.
Impairment of intermediate somatosensory function in corticobasal syndrome
Authors: Matsuda Kana , Satoh Masayuki , Tabei Ken-ichi , Ueda Yukito , Taniguchi Akira , Matsuura Keita , Asahi Masaru , Ii Yuichiro , Niwa Atsushi , Tomimoto Hidekazu
Published: July 2020

Corticobasal syndrome (CBS) is characterized by unilateral atrophy of the brain. New diagnostic criteria for CBS include intermediate somatosensory dysfunction. Here, we aimed to carefully examine intermediate somatosensory function to identify tests which can assess impairment in CBS patients. Using voxel-based morphometry (VBM), we also aimed to show the anatomical bases of these impairments. Subjects included 14 patients diagnosed with CBS and 14 patients with Parkinson's disease (PD). Patients were evaluated using intermediate somatosensory tests and neuropsychological assessments. VBM was used to analyze differences in gray matter volumes between CBS and PD patients. In the PD group, no tests showed a significant difference between the dominant-side onset and the non-dominant-side onset. In the CBS group, all tests showed worse scores on the affected side. For detecting intermediate somatosensory dysfunction in CBS, two tests are recommended: tactile object naming and 2-point discrimination. VBM analysis showed that the volume of the left post- and pre-central gyrus, and both sides of the supplementary motor area were significantly decreased in the CBS group compared to the PD group. Although CBS remains untreatable, early and correct diagnosis is possible by performing close examination of intermediate somatosensory function.
Aberration retrieval by incorporating customized priors for estimating Zernike coefficients
Authors: Wang Bin , Wang Xiaofei , An Qichang
Published: July 2020

Zernike expansion is an important tool for aberration retrieval in the optical field. The Zernike coefficients in the expansion can be solved in a linear system from those focal region intensity images, which can be modeled by the extended Nijboer–Zernike approach. Here we point out that those coefficients usually follow from different prior distributions, and especially, their variances could be dramatically diverse. To incorporate the prior information, we further introduce customized penalties to those Zernike coefficients and adopt a global adaptive generative adjustment algorithm for estimating coefficients. Based on both simulated and real data, numerical experiments show that our method outperforms other conventional methods, and provides an estimate of Zernike coefficients with a low mean square error.
Prostaglandin E2 breaks down pericyte–endothelial cell interaction via EP1 and EP4-dependent downregulation of pericyte N-cadherin, connexin-43, and R-Ras
Authors: Perrot Carole Y. , Herrera Jose L. , Fournier-Goss Ashley E. , Komatsu Masanobu
Published: July 2020

A close association between pericytes and endothelial cells (ECs) is crucial to the stability and function of capillary blood vessels and microvessels. The loss or dysfunction of pericytes results in significant disruption of these blood vessels as observed in pathological conditions, including cancer, diabetes, stroke, and Alzheimer’s disease. Prostaglandin E2 (PGE2) is a lipid mediator of inflammation, and its tissue concentration is elevated in cancer and neurological disorders. Here, we show that the exposure to PGE2 switches pericytes to a fast-migrating, loosely adhered phenotype that fails to intimately interact with ECs. N-cadherin and connexin-43 in adherens junction and gap junction between pericytes and ECs are downregulated by EP-4 and EP-1-dependent mechanisms, leading to breakdown of the pericyte–EC interaction. Furthermore, R-Ras, a small GTPase important for vascular normalization and vessel stability, is transcriptionally repressed by PGE2 in an EP4-dependent manner. Mouse dermal capillary vessels lose pericyte coverage substantially upon PGE2 injection into the skin. Our results suggest that EP-mediated direct disruption of pericytes by PGE2 is a key process for vascular destabilization. Restoring pericyte–EC interaction using inhibitors of PGE2 signaling may offer a therapeutic strategy in cancer and neurological disorders, in which pericyte dysfunction contributes to the disease progression.
A new role for anandamide: defective link between the systemic and skin endocannabinoid systems in hypertrophic human wound healing
Authors: Correia-Sá Inês B. , Carvalho Cláudia M. , Serrão Paula V. , Loureiro Ana I. , Fernandes-Lopes Carlos , Marques Marisa , Vieira-Coelho Maria A.
Published: July 2020

The use of cannabinoids to treat fibrotic skin diseases is an emergent issue. Therefore, we aimed to evaluate systemic and skin endocannabinoid responses in the wound-healing process in humans. A prospective study was performed in 50 patients who underwent body-contouring surgery. Anandamide (N-arachidonoylethanolamine, AEA), 2-arachidonoylglycerol (2-AG), palmitoylethanolamide (PEA) and oleoylethanolamide (OEA) were quantified using LC–MS/MS. Ten (20%) patients developed hypertrophic (HT) scars. No significant changes were observed between the normal (N) scar and HT scar groups in terms of plasma and skin endocannabinoids. Nevertheless, a positive correlation between plasma and skin AEA concentrations was found in the N group (r = 0.38, p = 0.015), which was absent in the HT group. Moreover, the AEA concentration was significantly lower in HT scar tissue than in normal scar tissue (0.77 ± 0.12 ng/g vs 1.15 ± 0.15 ng/g, p < 0.001). Interestingly, in all patients, the surgical intervention produced a time-dependent effect with a U shape for AEA, PEA and OEA plasma concentrations. In contrast, 2-AG plasma concentrations increased 5 days after surgery and were reduced and stabilized 3 months later. These results suggest crosstalk between systemic and local skin endocannabinoid systems during human wound healing. AEA appears to be the most likely candidate for this link, which is deficient in patients with HT scars.
Autoantibodies from SLE patients induce programmed cell death in murine fibroblast cells through interaction with TNFR1 receptor
Authors: Sharapova Tatiana N. , Romanova Elena A. , Soshnikova Natalia V. , Belogurov Alexey A. , Lomakin Yakov A. , Sashchenko Lidia P. , Yashin Denis V.
Published: July 2020

Various pathological processes are known to be associated with the production of IgG autoantibodies, which have high affinity for self-antigens and often cause tissue injury and the development of autoimmune diseases. However, the mechanism of their cytotoxic activity is not clearly understood yet. Here, we have shown that the action of these autoantibodies on cells expressing TNFR1 (the cell surface receptor for TNFα) can cause both caspase-dependent apoptosis and necroptosis of these cells, with suppression of apoptosis resulting in switching to RIP1-dependent necroptosis. Analysis of necroptotic mechanisms has shown that a critical point of necroptosis is phosphorylation of RIP1 and RIP3 kinases, which is followed by the involvement of lysosomes and mitochondria in this process. The induction of cytotoxicity is initiated by the interaction of autoantibodies with TNFR1, and autoantibodies can therefore be regarded as a new functional ligand for this receptor. The innate immunity protein Tag7 (PGLYRP1) described in our recent studies is also a ligand for TNFR1 and competes with autoantibodies for binding with it. Supposedly, the cytotoxic effect of autoantibodies is one of the factors responsible for autoimmune diseases that lead to tissue injury.
Preparation and modeling of three‐layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release
Authors: Milosevic Miljan , Stojanovic Dusica B. , Simic Vladimir , Grkovic Mirjana , Bjelovic Milos , Uskokovic Petar S. , Kojic Milos
Published: July 2020

The authors present the preparation procedure and a computational model of a three‐layered fibrous scaffold for prolonged drug release. The scaffold, produced by emulsion/sequential electrospinning, consists of a poly(d,l-lactic-co-glycolic acid) (PLGA) fiber layer sandwiched between two poly(ε-caprolactone) (PCL) layers. Experimental results of drug release rates from the scaffold are compared with the results of the recently introduced computational finite element (FE) models for diffusive drug release from nanofibers to the three-dimensional (3D) surrounding medium. Two different FE models are used: (1) a 3D discretized continuum and fibers represented by a simple radial one-dimensional (1D) finite elements, and (2) a 3D continuum discretized by composite smeared finite elements (CSFEs) containing the fiber smeared and surrounding domains. Both models include the effects of polymer degradation and hydrophobicity (as partitioning) of the drug at the fiber/surrounding interface. The CSFE model includes a volumetric fraction of fibers and diameter distribution, and is additionally enhanced by using correction function to improve the accuracy of the model. The computational results are validated on Rhodamine B (fluorescent drug l) and other hydrophilic drugs. Agreement with experimental results proves that numerical models can serve as efficient tools for drug release to the surrounding porous medium or biological tissue. It is demonstrated that the introduced three-layered scaffold delays the drug release process and can be used for the time-controlled release of drugs in postoperative therapy.
Assessment of the effects of sugammadex on coagulation profiles using thromboelastographic parameters
Authors: Kang Woon-Seok , Lim Hoyoung , Kim Byung-Soo , Lee Yeaji , Hahm Kyung-Don , Kim Seong-Hyop
Published: July 2020

This study evaluated the effects of sugammadex at conventional doses of 2 and 4 mg/kg on the coagulation profile by analyzing thromboelastographic parameters and performing a traditional laboratory coagulation analysis. A total of 100 patients undergoing arthroscopic shoulder surgery were enrolled. The patients were randomly divided into the 2 mg and 4 mg groups. The laboratory coagulation test and thromboelastographic analysis were performed before and 15 min after administering sugammadex. Prothrombin time (PT) was significantly prolonged after sugammadex administration than before it in intragroup comparisons of the 2 mg group (12.8 ± 0.6 s vs. 13.6 ± 0.7 s, p < 0.001) and the 4 mg group (13.0 ± 0.5 s vs. 13.7 ± 0.5 s, p < 0.001). R time, derived from thromboelastography, was also significantly prolonged after sugammadex administration (4.7 ± 1.8 min vs. 5.8 ± 2.1 min, p = 0.005). In conclusion, the conventional doses of 2 or 4 mg/kg sugammadex prolonged PT. Sugammadex 4 mg/kg also prolonged R time, although the value was within the normal range. Therefore, physicians should be cautious with the higher sugammadex dose, particularly in patients with a high risk of bleeding because the higher dose was associated with less coagulation.

Trial registration: KCT0002133 (https://cris.nih.go.kr).
Publisher Correction: Temporal rate is not a distinct perceptual metric
Authors: Motala Aysha , Heron James , McGraw Paul V. , Roach Neil W. , Whitaker David
Published: July 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
NMR Spectroscopy in the Study of the Structure and Dynamics of Gels
Authors: Shapiro Yury E.
Published: July 2020

Nuclear magnetic resonance (NMR) spectroscopy in combination with FTIR, X-ray diffractometry, electron microscopy and other instrumental techniques is rewarding in the study of the morphology, molecular structure and component dynamics of gel networks. For example, structural quantities such as the composition of polymers, microtacticity, sequence distribution, branching, crosslinking and molecular weight can be determined from the chemical shifts and signal intensities in NMR spectra, while more sophisticated experiments, i.e., measurements of spin relaxation times, nuclear Overhauser enhancement (NOE), magnetization transfer (MT), chemical exchange saturation transfer (CEST), multiple-quantum (MQ) coherencies, and the pulsed field gradient (PFG) technique, can give detailed information on the molecular organization and morphology of gels, as well as the internal mobility of the constituents of the gel. In this chapter, the capabilities of all these NMR methods will be discussed in the context of comprehensive studies of hydrogels and organogels. A special emphasis is put on the interplay between the morphology of the gel systems, the molecular mobility of their constituents and the intermolecular interactions.
Cells in Gels: NMR Studies
Authors: Kuchel Philip W. , Shishmarev Dmitry
Published: July 2020

Cells growing or suspended in gels of various types, whether biological or synthetic, have been studied over many decades, using light microscopy and biochemical analyses. More recently, NMR spectroscopy has also been applied to these systems, beginning with exploring perfused cells in solid blocks and later with the cells supported in small spheres or threads of alginate and agarose gels. Pulsed magnetic field gradient spin-echo (PGSE) NMR has been used to understand the factors that affect nutrient diffusion in gel threads and spheres, and more recently gelatin gel has been used as a variably distortable medium in which to manipulate the cell shape. The latter studies exposed a link (for the first time) between the red blood cell shape and rates of glycolysis and transmembrane cation flux. The experimental technology and results of these studies are described here along with hypotheses to give a mechanistic basis to the findings, which entail several macromolecular participants, including the mechanosensitive cation channel Piezo1.
Gel-based Radiation Dosimetry Using Quantitative MRI
Authors: De Deene Y.
Published: July 2020

By dissolving radiation sensitive chemicals into a gel matrix, a three-dimensional (3D) radiation dosimeter can be manufactured. These dosimeters can be used as anthropomorphic shape radiation dosimeters for dose verification of modern radiotherapy treatments. A first class of 3D radiation dosimeters is Fricke gel dosimeters, where the active radiation sensitive component is a bivalent cation such as the ferrous ion (Fe2+), which is oxidized upon irradiation. The oxidation reaction results in a change in the spin–lattice (R1) and spin–spin relaxation rates (R2), which can be mapped with MRI. A second class of 3D radiation dosimeters is polymer gel dosimeters, which are based on vinyl or acrylate monomers that are dissolved in a gelatin or agarose gel. When exposed to radiation, a dose dependent radical polymerization occurs. The amount of entangled or radiation induced grafted polymer is dose dependent and can be read out by use of MRI, optical scanning techniques or X-ray CT. It is mainly the spin–spin relaxation rate (R2) that is affected in polymer gel dosimeters. A third class is based on the radiation induced conversion of a coloured dye such as leuco-malachite green in the presence of a radical initiator. The coloured dye and radical initiator are mostly hydrophobic and are suspended in a gel matrix as micelles. These 3D dosimeters do not result in significant changes in NMR properties, but can be read out optically.
Gel Phantoms for Dynamic Contrast Enhanced MRI and Fluor-19 MRI Oximetry
Authors: Baete S. H. , De Deene Y.
Published: July 2020

Dynamic contrast enhanced (DCE) and oximetry MRI are valuable clinical tools. In order to maximize clinical effectiveness, though, there is a need for quantification and standardization; reproducible phantoms play a key role in this process. Phantoms for both methods require vascularisation and specific tissue properties in the extra-luminal space. While hollow fibre modules tackle the first requirement, gels are ideally suited to simulate contrast absorption or oxygen consumption. We review phantoms for DCE and oximetry MRI using gels and describe a 19F MRI oximetry phantom in detail. In this phantom, yeast cells suspended in a gelatine gel surrounding dialysis fibres simulate oxygen consumption by somatic cells in vivo. Several hypoxia situations can be recreated by adjusting the oxygen inflow, thus allowing for comparison of (19F) MRI oximetry markers and methods.
Plasmonic tweezers for optical manipulation and biomedical applications
Authors: Tan Hongtao , Hu Huiqian , Huang Lin , Qian Kun
Published: July 2020

This comprehensive minireview highlights the recent research on the subtypes, optical manipulation, and biomedical applications of plasmonic tweezers.
An optimized protocol for high precision measurement of 87Sr/86Sr using a Neptune Plus multi-collector inductively coupled plasma mass spectrometer: evaluation of different cone combinations for Sr isotope determination
Authors: Zhou Ting , Qi Liang , Fan Haifeng , Yin Runsheng
Published: July 2020

The effect of sample gas flow rate on the β88Sr/86Sr of the two cone combinations.
MOF-derived ultrasmall CoSe2 nanoparticles encapsulated by an N-doped carbon matrix and their superior lithium/sodium storage properties
Authors: Kong Fanjun , Wang Jian , Chen Jiyun , Tao Shi , Qian Bin , Luo Hongmei
Published: July 2020

We rationally design a hybrid composite with ultrasmall CoSe2 nanoparticles encapsulated by N-doped carbon matrix. The excellent electrochemical performance of composite can be owing to the synergistic effect of N-doped carbon matrix and ultrasmall CoSe2 nanoparticles.
Designing efficient Bi2Fe4O9 photoanodes via bulk and surface defect engineering
Authors: Monny Sabiha Akter , Wang Zhiliang , Lin Tongen , Chen Peng , Luo Bin , Wang Lianzhou
Published: July 2020

An efficient Bi2Fe4O9 photoanode can be fabricated through surface and bulk defect engineering to achieve a state-of-the-art photoresponse.
Two zinc coordination polymers with photochromic behaviors and photo-controlled luminescence properties
Authors: Wang Yi-Jun , Wang Shen-Yu , Zhang Yue , Xia Bin , Li Quan-Wen , Wang Qing-Lun , Ma Yue
Published: July 2020

Two new coordination polymers, [Zn(3-NDI)0.5(NDC)(DMF)]n (1) and {[Zn1.5(3-NDI)0.5(BDC)1.5]·2.5DMF}n (2), were synthesized. Both complexes show photochromic behaviors and have obvious fluorescence quenching behaviors upon irradiation.
The structural elucidation of aqueous H3BO3 solutions by DFT and neutron scattering studies
Authors: Zhou Yongquan , Yamaguchi Toshio , Zhang Wenqian , Ikeda Kazutaka , Yoshida Koji , Zhu Fayan , Liu Hongyan
Published: July 2020

The structure of aqueous H3BO3 solutions was studied via neutron scattering and EPSR modelling. B(OH)3 forms three kinds of molecular clusters in aqueous solutions. Their relative contents are both concentration- and temperature-sensitive.
Promising catalytic activity by non-thermal plasma synthesized SBA-15-supported metal catalysts in one-step plasma-catalytic methane conversion to value-added fuels
Authors: Chawdhury Piu , Bhargavi K. V. S. S. , Selvaraj M. , Subrahmanyam Ch.
Published: July 2020

Plasma-reduced metal nanoparticles encapsulated in an ordered mesoporous silica catalyst (SBA-15) effectively convert methane to liquid oxygenates in assistance of DBD-discharge.
Experimental and theoretical investigation of the chemical exfoliation of Cr-based MAX phase particles
Authors: Tran Minh Hai , Malik Ali M. , Dürrschnabel Michael , Regoutz Anna , Thakur Pardeep , Lee Tien-Lin , Perera Delwin , Molina-Luna Leopoldo , Albe Karsten , Rohrer Jochen , Birkel Christina S.
Published: July 2020

Experimental and theoretical evidence of the unexfoliability of Cr2GaC MAX phase particles in aqueous hydrofluoric acid.
Radii-dependent self-assembly of chiral lanthanide complexes: synthesis, chirality, and single-molecule magnet behavior
Authors: Li Ge , Zhao Xiaoxi , Han Qingxin , Wang Li , Liu Weisheng
Published: July 2020

Here we report the radii-dependent self-assembly of chiral lanthanide complexes and the single-molecule magnet behavior of the Dy5 complexes.
A practical guide to calculate the isosteric heat/enthalpy of adsorption via adsorption isotherms in metal–organic frameworks, MOFs
Authors: Nuhnen Alexander , Janiak Christoph
Published: July 2020

This Perspective presents the procedure of the common Freundlich–Langmuir fit/Clausius–Clapeyron approach and the virial fit of adsorption isotherms with usable Excel sheets and Origin files for the subsequent derivation of ΔHads.
Exceptionally low charge trapping enables highly efficient organic bulk heterojunction solar cells
Authors: Wu Jiaying , Lee Jinho , Chin Yi-Chun , Yao Huifeng , Cha Hyojung , Luke Joel , Hou Jianhui , Kim Ji-Seon , Durrant James R.
Published: July 2020

In this study, we investigate the underlying origin of the high performance of PM6:Y6 organic solar cells.
The opposite effects of Antarctic krill oil and arachidonic acid-rich oil on bone resorption in ovariectomized mice
Authors: Zhan Qiping , Tian Yingying , Han Lihua , Wang Kai , Wang Jingfeng , Xue Changhu
Published: July 2020

The opposite effects and mechanism of AKO and AAO in the regulation of bone resorption in postmenopausal osteoporosis were systematically investigated to support the recommendations on fatty acid types in dietary oils for people with osteoporosis.
The anomaly in bioactive sol–gel borate glasses
Authors: Lepry William C. , Nazhat Showan N.
Published: July 2020

The anomaly in bioactive sol–gel borate glasses: impact of alkaline earth modifier content on both structural and textural properties.
4-Nitrophenyl activated esters are superior synthons for indirect radiofluorination of biomolecules
Authors: Haskali Mohammad B. , Farnsworth Ashleigh L. , Roselt Peter D. , Hutton Craig A.
Published: July 2020

A comparative study of PNP- and TFP-activated esters of radiolabelled prosthetic groups demonstrates the superiority of PNP esters in terms of stability and yields for use in one-step radiolabelling of small molecules and peptides.
Chromium based metal–organic framework MIL-101 decorated palladium nanoparticles for the methanolysis of ammonia-borane
Authors: Caner Nurdan , Yurderi Mehmet , Bulut Ahmet , Kanberoglu Gulsah Saydan , Kaya Murat , Zahmakiran Mehmet
Published: July 2020

Pd@MIL-101 synthesized by a novel and facile approach acts as a highly active nanocatalyst (TOF = 1080 min−1) in the methanolysis of ammonia-borane (NH3BH3) under air at room temperature.
Monolithic ZnxCe1−xO2 catalysts for catalytic synthesis of dimethyl carbonate from CO2 and methanol
Authors: Chen Yongdong , Tang Qiang , Ye Zhongbin , Li Yue , Yang You , Pu Haoyu , Li Gao
Published: July 2020

The schematic diagram of reactor module comprised of honeycomb ceramic monolith with the catalysts for the synthesis of DMC.
Development of “dual-key-and-lock” responsive probes for biosensing and imaging
Authors: Feng Huan , Meng Qingtao , Ta Hang T. , Zhang Run
Published: July 2020

Recent advances in the development of “dual-key-and-lock” responsive probes for accurate detection of various biomolecules are reviewed.
Transport of artificial virus-like nanocarriers through intestinal monolayers via microfold cells
Authors: Tong Tianjian , Qi Yijun , Bussiere Luke D. , Wannemuehler Michael , Miller Cathy L. , Wang Qun , Yu Chenxu
Published: July 2020

Compared with subcutaneous or intramuscular routes for vaccination, vaccine delivery via the gastrointestinal mucosa has tremendous potential as it is easy to administer and pain-free.
Synthesis of 2-aryl quinazolinones via iron-catalyzed cross-dehydrogenative coupling (CDC) between N–H and C–H bonds
Authors: Jang Yoonkyung , Lee Seok Beom , Hong Junhwa , Chun Simin , Lee Jeeyeon , Hong Suckchang
Published: July 2020

Iron-catalyzed cross-dehydrogenative coupling between methyl arenes and anthranilamides for the direct synthesis of quinazolinones.
Detection of biomarkers in body fluids using bioprobes based on aggregation-induced emission fluorogens
Authors: Zhang Xinyi , Yao Bicheng , Hu Qi , Hong Yuning , Wallace Angus , Reynolds Karen , Ramsey Carolyn , Maeder Anthony , Reed Richard , Tang Youhong
Published: July 2020

This review describes the constituents and clinical biomarkers in urine, saliva, and sweat, and the role of currently developed AIE bioprobes that can quantitatively detect disease-related biomarkers in these biofluids.
Iron–cobalt-catalyzed heterotrimerization of alkynes and nitriles to polyfunctionalized pyridines
Authors: Xie Yufang , Wu Chengjuan , Jia Changhao , Tung Chen-Ho , Wang Wenguang
Published: July 2020

The iron(ii)–cobalt(ii) co-catalyzed heterotrimerization of alkynes and nitriles enables the synthesis of 2,3,4,5,6-pentafunctionalized pyridines in a single step.
Tunable magnetic textures and excitation modes in FePt multilayer films
Authors: Bi Mei , Yuan Le , Wang Xin , Weng Xiaolong , Deng Longjiang
Published: July 2020

Micromagnetic simulations have been performed to investigate the magnetic textures and dynamic properties of FePt-based multilayer films.
Cell-loaded injectable gelatin/alginate/LAPONITE® nanocomposite hydrogel promotes bone healing in a critical-size rat calvarial defect model
Authors: Liu Bin , Li Junqin , Lei Xing , Miao Sheng , Zhang Shuaishuai , Cheng Pengzhen , Song Yue , Wu Hao , Gao Yi , Bi Long , Pei Guoxian
Published: July 2020

An injectable cell-laden nanocomposite hydrogel simulate natural ECM, promote cell proliferation, and accelerate bone healing of critical-size rat calvarial defects.
The antioxidant potential of peptides obtained from the spotted babylon snail (Babylonia areolata) in treating human colon adenocarcinoma (Caco-2) cells
Authors: Petsantad Putcha , Sangtanoo Papassara , Srimongkol Piroonporn , Saisavoey Tanatorn , Reamtong Onrapak , Chaitanawisuti Ninnaj , Karnchanatat Aphichart
Published: July 2020

The isolation and subsequent identification of the two novel antioxidant peptides, HTYHEVTKH, and WPVLAYHF from the spotted babylon snail was achieved. In the Caco-2 cell line, two synthetic peptides produced a dose-dependent response on antioxidant activity.
Effects of high mechanical treatment and long-term annealing on crystal structure and thermal stability of Ti2O3 nanocrystals
Authors: Valeeva Albina A. , Nazarova Svetlana Z. , Schröttner Hartmuth , Gerasimov Evgeny Yu. , Rempel Andrey A.
Published: July 2020

The effect of high-energy milling and long-term annealing on the stability of Ti2O3 nanocrystals was studied using a magnetic susceptibility method.
Catalyst control of selectivity in the C–O bond alumination of biomass derived furans
Authors: Hooper Thomas N. , Brown Ryan K. , Rekhroukh Feriel , Garçon Martí , White Andrew J. P. , Costa Paulo J. , Crimmin Mark R.
Published: July 2020

Non-catalysed and catalysed reactions of aluminium reagents with furans, dihydrofurans and dihydropyrans were investigated and lead to ring-expanded products due to the insertion of the aluminium reagent into a C–O bond of the heterocycle.
A covalent organic cage compound acting as a supramolecular shadow mask for the regioselective functionalization of C60
Authors: Leonhardt Viktoria , Fimmel Stefanie , Krause Ana-Maria , Beuerle Florian
Published: July 2020

The taming of the Prato reaction: a covalent organic cage compound serves as a supramolecular template for the regioselective functionalization of C60.
Broadband fluorescence reveals mechanistic differences in excited-state proton transfer to protic and aprotic solvents
Authors: Verma Pragya , Rosspeintner Arnulf , Dereka Bogdan , Vauthey Eric , Kumpulainen Tatu
Published: July 2020

Time-resolved broadband fluorescence facilitates direct observation of reaction intermediates in excited-state proton transfer to solvent in protic and aprotic solvents.
Polyimide-based photocatalysts: rational design for energy and environmental applications
Authors: Chu Sheng , Pan Yuyang , Wang Ying , Zhang Huiyan , Xiao Rui , Zou Zhigang
Published: July 2020

Recent progress in the development of polyimide-based photocatalyst for energy and environmental applications has been reviewed.
A ratiometric optical strategy for bromide and iodide ion sensing based on target-induced competitive coordination of a metal–organic nanosystem
Authors: Fan Yu Zhu , Han Lei , Liu Shi Gang , Zhang Ying , Luo Hong Qun , Li Nian Bing
Published: July 2020

A metal–organic nanosystem constructed via coordination bonding-induced self-assembly is used for fluorescence and scattering ratiometric sensing of bromide and iodide ions.
Metamaterial and nanomaterial electromagnetic wave absorbers: structures, properties and applications
Authors: Zhou Jin , Liu Zhengqi , Liu Xiaoshan , Fu Guolan , Liu Guiqiang , Chen Jing , Wang Cong , Zhang Han , Hong Minghui
Published: July 2020

Perfect absorbers (PAs) are devices that can realize the annihilation of incident electromagnetic waves (EMWs) by eliminating reflection and transmission.
DNMT3b-mediated methylation of ZSWIM3 enhances inflammation in alcohol-induced liver injury via regulating TRAF2-mediated NF-κB pathway
Authors: Li Hai-Di , Chen Xin , Xu Jie-Jie , Du Xiao-Sa , Yang Yang , Li Juan-Juan , Yang Xiao-Juan , Huang Hui-Min , Li Xiao-Feng , Wu Ming-Fei , Zhang Chong , Zhang Chao , Li Zeng , Wang Hua , Meng Xiao-Ming , Huang Cheng , Li Jun
Published: July 2020

The regulation of macrophages during inflammatory responses is a crucial process in alcoholic liver disease (ALD) and aberrant macrophage DNA methylation is associated with inflammation. Our preliminary screening results of macrophage methylation in the present study demonstrated the zinc finger SWI2/SNF2 and MuDR (SWIM)-domain containing 3 (ZSWIM3) were hypermethylated in the 5′ untranslated region (5′-UTR) region. ZSWIM3, a novel zinc finger-chelate domain of SWIM, is predicted to function in DNA-binding and protein-binding interactions. Its expression was found to be consistently decreased in macrophages isolated from livers of ethyl alcohol (EtOH)-fed mice and in EtOH+lipopolysaccharide (LPS)-induced RAW264.7 cells. Over-expression of ZSWIM3 was found to attenuate chronic+binge ethanol feeding-induced liver injury and inhibit inflammatory responses in vivo. Enforced expression of ZSWIM3 in vitro was also found to have anti-inflammatory effects. Aberrant expression of ZSWIM3 in alcohol-induced liver injury (ALI) was found to be associated with hypermethylation. Analysis of CpG prediction indicated the presence of two methylated sites in the ZSWIM3 promoter region and methylation inhibitor and DNA methyltransferases (DNMTs)-siRNA transfection were found to restore down-regulated ZSWIM3. Chromatin immunoprecipitation (ChIP) assay and molecular docking affirmed the role of DNMT 3b (DNMT3b) as a principal regulator of ZSWIM3 expression. Mechanistically, ZSWIM3 might affect inflammation by binding with tumor necrosis factor receptor-associated factor 2 (TRAF2), which further mediates the activation of the nuclear transcription factor κB (NF-κB) pathway. The present study, therefore, provides detailed insights into the possible structure and function of ZSWIM3 and thus, contributes new substantial research in the elucidation of the pathogenesis of ALI.
The Relation Between Vocabulary Knowledge and Phonological Awareness in Children With Cochlear Implants
Authors: Lund Emily
Published: July 2020

Purpose

The purpose of this study was to evaluate the relation between lexical knowledge and phonological awareness performance of children with cochlear implants.

Method

Thirty children with cochlear implants (aged 5–7 years), 30 children with normal hearing matched for age, and 30 children with normal hearing matched for vocabulary size participated in the study. Children completed a vocabulary knowledge measure and three phonological awareness tasks with words that had high and low neighborhood density.

Results

Children with cochlear implants performed more poorly than their age-matched peers and similarly to their vocabulary-matched peers on phonological awareness tasks. When performance was analyzed according to the neighborhood density of the target word, children with cochlear implants and age-matched children performed better with high-density words. Across all groups, vocabulary size correlated significantly with phonological awareness performance.

Conclusion

Children with cochlear implants demonstrate delays in both vocabulary knowledge and phonological awareness performance, but children with cochlear implants appear to take advantage of lexical information similarly to their age-matched peers.
Improving primary frequency response in networked microgrid operations using multilayer perceptron‐driven reinforcement learning
Authors: Radhakrishnan Nikitha , Chakraborty Indrasis , Xie Jing , Thekkumparambath Mana Priya , Tuffner Francis K. , Bhattarai Bishnu P. , Schneider Kevin P.
Published: July 2020

Individual microgrids can improve the reliability of power systems during extreme events, and networked microgrids can further improve efficiency through resource sharing and increase the resilience of critical end‐use loads. However, networked microgrid operations can be subject to large transients due to switching and end‐use loads, which can cause dynamic instability and lead to system collapse. These transients are especially prevalent in microgrids with high penetrations of grid‐following inverter‐connected renewable energy resources, which do not provide the system inertia or fast frequency response needed to mitigate the transients. One potential mitigation is to engage the existing generator controls to reduce system voltage in response to a frequency deviation, thereby reducing load and improving primary frequency response. This study investigates the use of a reinforcement‐learning‐based controller trained over several switching transient scenarios to modify generator controls during large frequency deviations. Compared to previously used proportional–integral controllers, the proposed controller can improve primary frequency response while adapting to changes in system topologies and conditions.