bluuebunny/crossref_metadata_2025 huggingface dataset:
The heat shock response, determined by QuantiGene multiplex, is impaired in HD mouse models and not caused by HSF1 reduction
Authors: Gomez-Paredes Casandra , Mason Michael A. , Taxy Bridget A. , Papadopoulou Aikaterini S. , Paganetti Paolo , Bates Gillian P.
Published: April 2021

Huntington’s disease (HD) is a devastating neurodegenerative disorder, caused by a CAG/polyglutamine repeat expansion, that results in the aggregation of the huntingtin protein, culminating in the deposition of inclusion bodies in HD patient brains. We have previously shown that the heat shock response becomes impaired with disease progression in mouse models of HD. The disruption of this inducible arm of the proteostasis network is likely to exacerbate the pathogenesis of this protein-folding disease. To allow a rapid and more comprehensive analysis of the heat shock response, we have developed, and validated, a 16-plex QuantiGene assay that allows the expression ofHsf1and nine heat shock genes, to be measured directly, and simultaneously, from mouse tissue. We used this QuantiGene assay to show that, following pharmacological activation in vivo, the heat shock response impairment in tibialis anterior, brain hemispheres and striatum was comparable between zQ175 and R6/2 mice. In contrast, although a heat shock impairment could be detected in R6/2 cortex, this was not apparent in the cortex from zQ175 mice. Whilst the mechanism underlying this impairment remains unknown, our data indicated that it is not caused by a reduction in HSF1 levels, as had been reported.
Sensory block level prediction of spinal anaesthesia with 0.5% hyperbaric bupivacaine: a retrospective study
Authors: Huang Yu-Yin , Chang Kuang-Yi
Published: April 2021

There is still no consensus on how to determine the dose of spinal anaesthesia with adequate sensory block for a planned surgery. This retrospective study aimed to explore the associations of miscellaneous factors with peak sensory block level after spinal anaesthesia with hyperbaric bupivacaine, and to construct a predictive model for single-shot spinal anaesthesia. We collected the records of 401 non-pregnant adults who underwent spinal anaesthesia with 0.5% hyperbaric bupivacaine at the L3–4 or L4–5 intervertebral space for lower body surgeries. Multiple linear regression analysis was used to investigate predictors of the block level and build up the predictive model. Five variables were identified as independent predictors of the peak sensory block level, including bupivacaine dose, height, weight, gender and age. The predictive model for peak block level after spinal anaesthesia could be expressed as a formula with these five variables and the estimated predictive power was 0.72. Based on this model, it is possible to determine a reasonable dose of hyperbaric bupivacaine for spinal anaesthesia, which gives adequate sensory block required for diverse surgical procedures in various patients and could be considered as a dose reference for sensory block height in spinal anaesthesia.
Identification of candidate PAX2-regulated genes implicated in human kidney development
Authors: Yamamura Yuta , Furuichi Kengo , Murakawa Yasuhiro , Hirabayashi Shigeki , Yoshihara Masahito , Sako Keisuke , Kitajima Shinji , Toyama Tadashi , Iwata Yasunori , Sakai Norihiko , Hosomichi Kazuyoshi , Murphy Philip M. , Tajima Atsushi , Okita Keisuke , Osafune Kenji , Kaneko Shuichi , Wada Takashi
Published: April 2021

PAX2is a transcription factor essential for kidney development and the main causative gene for renal coloboma syndrome (RCS). The mechanisms of PAX2 action during kidney development have been evaluated in mice but not in humans. This is a critical gap in knowledge since important differences have been reported in kidney development in the two species. In the present study, we hypothesized that key human PAX2-dependent kidney development genes are differentially expressed in nephron progenitor cells from induced pluripotent stem cells (iPSCs) in patients with RCS relative to healthy individuals. Cap analysis of gene expression revealed 189 candidate promoters and 71 candidate enhancers that were differentially activated by PAX2 in this system in three patients with RCS withPAX2mutations. By comparing this list with the list of candidate Pax2-regulated mouse kidney development genes obtained from the Functional Annotation of the Mouse/Mammalian (FANTOM) database, we prioritized 17 genes. Furthermore, we ranked three genes—PBX1,POSTN, andITGA9—as the top candidates based on closely aligned expression kinetics with PAX2 in the iPSC culture system and susceptibility to suppression by a Pax2 inhibitor in cultured mouse embryonic kidney explants. Identification of these genes may provide important information to clarify the pathogenesis of RCS, human kidney development, and kidney regeneration.
Therapeutic effects of micro-RNAs in preclinical studies of acute kidney injury: a systematic review and meta-analysis
Authors: Zankar Sarah , Trentin-Sonoda Mayra , Viñas Jose L. , Rodriguez Rosendo A. , Bailey Adrian , Allan David , Burns Kevin D.
Published: April 2021

AKI has a high mortality rate, may lead to chronic kidney disease, and effective therapies are lacking. Micro-RNAs (miRNAs) regulate biologic processes by potently inhibiting protein expression, and pre-clinical studies have explored their roles in AKI. We conducted a systematic review and meta-analysis of miRNAs as therapeutics in pre-clinical AKI. Study screening, data extraction, and quality assessments were performed by 2 independent reviewers. Seventy studies involving 42 miRNA species were included in the analysis. All studies demonstrated significant effects of the miRNA intervention on kidney function and/or histology, with most implicating apoptosis and phosphatase and tensin homolog (PTEN) signaling. Fourteen studies (20.0%) examined the effect of miRNA-21 in AKI, and meta-analysis demonstrated significant increases in serum creatinine and kidney injury scores with miR-21 antagonism and pre-conditioning. No studies reported on adverse effects of miRNA therapy. Limitations also included lack of model diversity (100% rodents, 61.4% ischemia–reperfusion injury), and predominance of male sex (78.6%). Most studies had an unclear risk of bias, and the majority of miRNA-21 studies were conducted by a single team of investigators. In summary, several miRNAs target kidney function and apoptosis in pre-clinical AKI models, with data suggesting that miRNA-21 may mediate protection and kidney repair.

Systematic review registration ID: CRD42019128854.
Targeted transcriptome analysis using synthetic long read sequencing uncovers isoform reprograming in the progression of colon cancer
Authors: Liu Silvia , Wu Indira , Yu Yan-Ping , Balamotis Michael , Ren Baoguo , Ben Yehezkel Tuval , Luo Jian-Hua
Published: April 2021

The characterization of human gene expression is limited by short read lengths, high error rates and large input requirements. Here, we used a synthetic long read (SLR) sequencing approach, LoopSeq, to generate accurate sequencing reads that span full length transcripts using standard short read data. LoopSeq identified isoforms from control samples with 99.4% accuracy and a 0.01% per-base error rate, exceeding the accuracy reported for other long-read technologies. Applied to targeted transcriptome sequencing from colon cancers and their metastatic counterparts, LoopSeq revealed large scale isoform redistributions from benign colon mucosa to primary colon cancer and metastatic cancer and identified several previously unknown fusion isoforms. Strikingly, single nucleotide variants (SNVs) occurred dominantly in specific isoforms and some SNVs underwent isoform switching in cancer progression. The ability to use short reads to generate accurate long-read data as the raw unit of information holds promise as a widely accessible approach in transcriptome sequencing.
Neutron reflectometry and NMR spectroscopy of full-length Bcl-2 protein reveal its membrane localization and conformation
Authors: Mushtaq Ameeq Ul , Ådén Jörgen , Clifton Luke A. , Wacklin-Knecht Hanna , Campana Mario , Dingeldein Artur P. G. , Persson Cecilia , Sparrman Tobias , Gröbner Gerhard
Published: April 2021

B-cell lymphoma 2 (Bcl-2) proteins are the main regulators of mitochondrial apoptosis. Anti-apoptotic Bcl-2 proteins possess a hydrophobic tail-anchor enabling them to translocate to their target membrane and to shift into an active conformation where they inhibit pro-apoptotic Bcl-2 proteins to ensure cell survival. To address the unknown molecular basis of their cell-protecting functionality, we used intact human Bcl-2 protein natively residing at the mitochondrial outer membrane and applied neutron reflectometry and NMR spectroscopy. Here we show that the active full-length protein is entirely buried into its target membrane except for the regulatory flexible loop domain (FLD), which stretches into the aqueous exterior. The membrane location of Bcl-2 and its conformational state seems to be important for its cell-protecting activity, often infamously upregulated in cancers. Most likely, this situation enables the Bcl-2 protein to sequester pro-apoptotic Bcl-2 proteins at the membrane level while sensing cytosolic regulative signals via its FLD region.
Regulatory effect of non-starch polysaccharides from purple sweet potato on intestinal microbiota of mice with antibiotic-associated diarrhea
Authors: Bie Nana , Duan Shengquan , Meng Meng , Guo Mingzhu , Wang Chunling
Published: April 2021

The overall experimental design of this work to analyze the structural characteristics of purple sweet potato polysaccharides and their regulation effect on the intestinal microbial environment of mice with antibiotic-associated diarrhea.
Polymorphs and hydrates of the anticancer drug erlotinib: X-ray crystallography, phase transition and biopharmaceutical studies
Authors: Thorat Shridhar H. , George Christy P. , Shaligram Parth S. , P. R. Suresha , Gonnade Rajesh G.
Published: April 2021

The anticancer drug erlotinib revealed two polymorphs and two hydrates. The metastable polymorph and hydrates converted to the stable polymorph, which displayed solution-mediated transformation into the monohydrate at the lowest water activity.
Quantitative relationship between the structures and properties of VOCs and SOA formation on the surfaces of acidic aerosol particles
Authors: Tang Chunxue , Ding Keyi , Liu Yaoze , Yu Shengping , Chen Junhui , Feng Xiaoqiong , Zhang Chunchun , Chen Junxian
Published: April 2021

The quantitative relationship was found through the experimental fractional aerosol coefficients (FACs) as a function of the two variables the total valid interactions (Tg) and the diffusion coefficient (D), with R square 0.94.
Nickel–cobalt oxalate as an efficient non-precious electrocatalyst for an improved alkaline oxygen evolution reaction
Authors: Ghosh Sourav , Jana Rajkumar , Ganguli Sagar , Inta Harish Reddy , Tudu Gouri , Koppisetti Heramba V. S. R. M. , Datta Ayan , Mahalingam Venkataramanan
Published: April 2021

Nickel–cobalt oxalate (Ni2.5Co5C2O4–nH2O) based block-like nanostructure has been introduced as superior electrocatalyst compared to nickel–cobalt oxide (NiCo2O4) for alkaline water oxidation.
Unravelling the cooperative role of lattice strain on MnO2/TiO2 and MnO2/ZnO catalysts for the fast decomposition of hydrogen peroxide
Authors: Santhanaraj D. , Selvamani A. , Rajakumar K. , Joseph N. Ricky , Giridhar S. , Adinaveen T. , Sophie P. Leema , Ramkumar V.
Published: April 2021

The rate of decomposition of hydrogen peroxide was directly correlated with lattice strain, as derived from strain calculations.
Tunable electron property induced by B-doping in g-C3N4
Authors: Yang Bo , Bu Hongxia , Liu Xiaobiao
Published: April 2021

A novel graphitic carbon nitride material: g-C6N7B, with topological properties.
A comparison study of sodium ion- and potassium ion-modified graphitic carbon nitride for photocatalytic hydrogen evolution
Authors: Hu Siyu , Yu Anchi , Lu Rong
Published: April 2021

The ion size effect on graphitic carbon nitride is responsible for variations in its structure, optical and electronic properties, and hence the enhancement in photocatalytic hydrogen evolution.
Quantifying the influences of radiation therapy on deformability of human red blood cells by dual-beam optical tweezers
Authors: Inanc Medine Tuna , Demirkan Irem , Ceylan Cemile , Ozkan Alper , Gundogdu Ozcan , Goreke Utku , Gurkan Umut A. , Unlu Mehmet Burcin
Published: April 2021

Little is known about radiation therapy's possible effects on mechanical features of off-target cells such as human red blood cells. Here, irradiated human red blood cells were stretched using dual-beam optical tweezers and compared using the resulting deformability index.
Expanding excitation wavelengths for azobenzene photoswitching into the near-infrared range via endothermic triplet energy transfer
Authors: Isokuortti Jussi , Kuntze Kim , Virkki Matti , Ahmed Zafar , Vuorimaa-Laukkanen Elina , Filatov Mikhail A. , Turshatov Andrey , Laaksonen Timo , Priimagi Arri , Durandin Nikita A.
Published: April 2021

Triplet energy transfer enables efficient Z-to-E photoswitching of azobenzenes even with near-infrared light. Ultrafast intersystem crossing of azobenzene makes the process entropy-driven and enables the use of endothermic sensitizer-azobenzene pairs.
Human placental villous stromal extracellular matrix regulates fetoplacental angiogenesis in severe fetal growth restriction
Authors: Ji Shuhan , Gumina Diane , McPeak Kathryn , Moldovan Radu , Post Miriam D. , Su Emily J.
Published: April 2021

Pregnancies complicated by severe, early-onset fetal growth restriction with abnormal Doppler velocimetry (FGRadv) have a sparse villous vascular tree secondary to impaired angiogenesis. As endothelial cell (EC) and stromal matrix interactions are key regulators of angiogenesis, we investigated the role of placental stromal villous matrix on fetoplacental EC angiogenesis. We have developed a novel model of generating placental fibroblast (FB) cell-derived matrices (CDMs), allowing us to interrogate placenta-specific human EC and stromal matrix interactions and their effects on fetoplacental angiogenesis. We found that as compared with control ECs plated on control matrix, FGRadv ECs plated on FGRadv matrix exhibited severe migrational defects, as measured by velocity, directionality, accumulated distance, and Euclidean distance in conjunction with less proliferation. However, control ECs, when interacting with FGRadv CDM, also demonstrated significant impairment in proliferation and migratory properties. Conversely several angiogenic attributes were rescued in FGRadv ECs subjected to control matrix, demonstrating the importance of placental villous stromal matrix and EC-stromal matrix interactions in regulation of fetoplacental angiogenesis.
SN 2020bqj: A Type Ibn supernova with a long-lasting peak plateau
Authors: Kool E. C. , Karamehmetoglu E. , Sollerman J. , Schulze S. , Lunnan R. , Reynolds T. M. , Barbarino C. , Bellm E. C. , De K. , Duev D. A. , Fremling C. , Golkhou V. Z. , Graham M. L. , Green D. A. , Horesh A. , Kaye S. , Kim Y.-L. , Laher R. R. , Masci F. J. , Nordin J. , Perley D. A. , Phinney E. S. , Porter M. , Reiley D. , Rodriguez H. , van Roestel J. , Rusholme B. , Sharma Y. , Sfaradi I. , Soumagnac M. T. , Taggart K. , Tartaglia L. , Williams D. R. A. , Yan L.
Published: April 2021

Context. Type Ibn supernovae (SNe Ibn) are a rare class of stripped envelope supernovae interacting with a helium-rich circumstellar medium (CSM). The majority of the SNe Ibn reported in the literature display a surprising homogeneity in their fast-evolving lightcurves and are typically found in actively starforming spiral galaxies.

Aims. We present the discovery and the study of SN 2020bqj (ZTF20aalrqbu), a SN Ibn with a long-duration peak plateau lasting 40 days and hosted by a faint low-mass galaxy. We aim to explain its peculiar properties using an extensive photometric and spectroscopic data set.

Methods. We compare the photometric and spectral evolution of SN 2020bqj with regular SNe Ibn from the literature, as well as with other outliers in the SN Ibn subclass. We fit the bolometric and multi-band lightcurves with powering mechanism models such as radioactive decay and CSM interaction. We also model the host galaxy of SN 2020bqj.

Results. The risetime, peak magnitude and spectral features of SN 2020bqj are consistent with those of most SNe Ibn, but the SN is a clear outlier in the subclass based on its bright, long-lasting peak plateau and the low mass of its faint host galaxy. We show through modeling that the lightcurve of SN 2020bqj can be powered predominantly by shock heating from the interaction of the SN ejecta and a dense CSM, combined with radioactive decay. The peculiar Type Ibn SN 2011hw is a close analog to SN 2020bqj in terms of lightcurve and spectral evolution, suggesting a similar progenitor and CSM scenario. In this scenario a very massive progenitor star in the transitional phase between a luminous blue variable and a compact Wolf-Rayet star undergoes core-collapse, embedded in a dense helium-rich CSM with an elevated opacity compared to normal SNe Ibn, due to the presence of residual hydrogen. This scenario is consistent with the observed properties of SN 2020bqj and the modeling results.

Conclusions. SN 2020bqj is a compelling example of a transitional SN Ibn/IIn based on not only its spectral features, but also its lightcurve, host galaxy properties and the inferred progenitor properties. The strong similarity with SN 2011hw suggests this subclass may be the result of a progenitor in a stellar evolution phase that is distinct from those of progenitors of regular SNe Ibn.
Variation of the core lifetime and fragmentation scale in molecular clouds as an indication of ambipolar diffusion
Authors: Das Indrani , Basu Shantanu , André Philippe
Published: April 2021

Ambipolar diffusion likely plays a pivotal role in the formation and evolution of dense cores in weakly ionized molecular clouds. Linear analyses show that the evolutionary times and fragmentation scales are significantly greater than the hydrodynamic (Jeans) values even for clouds with mildly supercritical mass-to-flux ratios. We use values of fragmentation scales and growth times that correspond to typical ionization fractions within a molecular cloud, and apply these in the context of the observed estimated lifetime of prestellar cores and the observed number of such embedded cores forming in a parent clump. By varying a single parameter – the mass-to-flux ratio – over the range of observationally measured densities, we fit the range of estimated prestellar core lifetimes (∼0.1 to a few Myr) identified with Herschel as well as the number of embedded cores formed in a parent clump measured in Perseus with the Submillimeter Array. Our model suggests that the prestellar cores are formed with a transcritical mass-to-flux ratio and higher densities correspond to somewhat higher mass-to-flux ratios, but the normalized mass-to-flux ratio μ remains in the range 1 ≲ μ ≲ 2. Our best-fit model exhibits B ∝ n0.43 for prestellar cores because of the partial flux-freezing caused by ambipolar diffusion.
Evolution of anisotropic turbulence in the fast and slow solar wind: Theory and Solar Orbiter measurements
Authors: Adhikari L. , Zank G. P. , Zhao L.-L. , Telloni D. , Horbury T. S. , O’Brien H. , Evans V. , Angelini V. , Owen C. J. , Louarn P. , Fedorov A.
Published: April 2021

Aims.Solar Orbiter (SolO) was launched on February 9, 2020, allowing us to study the nature of turbulence in the inner heliopshere. We investigate the evolution of anisotropic turbulence in the fast and slow solar wind in the inner heliosphere using the nearly incompressible magnetohydrodynamic (NI MHD) turbulence model and SolO measurements.

Methods.We calculated the two dimensional (2D) and the slab variances of the energy in forward and backward propagating modes, the fluctuating magnetic energy, the fluctuating kinetic energy, the normalized residual energy, and the normalized cross-helicity as a function of the angle between the mean solar wind speed and the mean magnetic field (θUB), and as a function of the heliocentric distance using SolO measurements. We compared the observed results and the theoretical results of the NI MHD turbulence model as a function of the heliocentric distance.

Results.The results show that the ratio of 2D energy and slab energy of forward and backward propagating modes, magnetic field fluctuations, and kinetic energy fluctuations increases as the angle between the mean solar wind flow and the mean magnetic field increases fromθUB = 0° to approximatelyθUB = 90° and then decreases asθUB → 180°. We find that solar wind turbulence is a superposition of the dominant 2D component and a minority slab component as a function of the heliocentric distance. We find excellent agreement between the theoretical results and observed results as a function of the heliocentric distance.
Brustkrebsfrüherkennung bei Frauen mit erhöhten Erkrankungsrisiken
Authors: Püsken Michael , Rhiem Kerstin , Fallenberg Eva M.
Published: April 2021

Für Patientinnen und gesunde Ratsuchende mit einem erhöhten Erkrankungsrisiko für Brustkrebs besteht ein langjährig etabliertes Programm zur intensivierten Früherkennung und Nachsorge in den spezialisierten Zentren des Deutschen Konsortiums Familiärer Brust- und Eierstockkrebs (https://www.konsortium-familiaerer-brustkrebs.de/). Dabei kommt der MR-Mammografie aufgrund der sehr hohen Sensitivität beim Tumornachweis eine besondere Bedeutung zu.
Behçet’s Syndrome Complicated with Pulmonary Artery Thrombosis: Response to Tocilizumab Treatment
Authors: Eroglu Didem Sahin , Colaklar Anil , Ceran Alparslan , Sezer Serdar , Torgutalp Murat , Kinikli Gulay
Published: April 2021

Die Beteiligung der Lungenarterie ist eine seltene, aber tödliche Komplikation des Morbus Behçets (MB). Hier berichten wir über einen männlichen MB-Patienten mit zwei vaskulären Komplikationen, nämlich dem Budd-Chiari-Syndrom und der Pulmonalarterienthrombose. Der Patient litt unter einer rezidivierenden Lungenarterienthrombose, die gegen mehrere immunsuppressive Medikamente, einschließlich hochdosierter Glukokortikoide und dem Anti-TNF-Mittel Infliximab, refraktär war. Infolge mehrerer Rezidive wurde er effektiv mit Tocilizumab behandelt, wodurch auch eine vollständige Rekanalisation der thrombosierten Arterien erreicht wurde.
Implementierung eines globalen Behandlungsbudgets in der Psychiatrie – Welche Anreize, Voraussetzungen und Herausforderungen gibt es?
Authors: Schwarz Julian , Schmid Christine , Neumann Anne , Pfennig Andrea , Soltmann Bettina , Heinze Martin , von Peter Sebastian
Published: April 2021

Ziel Seit 2013 haben sich in Deutschland 22 psychiatrische Modellvorhaben nach § 64b SGB V (MV) gebildet, die auf Basis eines globalen Behandlungsbudgets (GBB) eine flexible und settingübergreifende Versorgung bieten. Als Teilprojekt der „PsychCare“-Studie werden die Anreize, Voraussetzungen und Herausforderungen von GBB untersucht.

Methode Es wurden Interviews und Fokusgruppen mit Mitarbeitenden (n = 29) aus Controlling und Management an 7 MV sowie 3 Krankenkassen (KK) geführt und qualitativ ausgewertet.

Ergebnisse Zentral für die Einführung von GBB sind die Kooperation sowie gemeinsame Steuerungsziele zwischen Kliniken und KK. Als herausfordernd werden u. a. die settingübergreifende Leistungsdokumentation und -steuerung sowie der parallele Betrieb von Modell- und Regelversorgung erlebt.

Schlussfolgerung GBB stellen einen starken Antrieb zur organisationalen Transformation für eine zukunftsweisende psychiatrische Versorgung dar. Bei der Weiterentwicklung von GBB sollte der bislang fehlende Kontrahierungszwang für alle Krankenkassen berücksichtigt werden.
Chemical Constituents from Chloranthus elatior and Their Inhibitory Effect on Human Dihydroorotate Dehydrogenase
Authors: Yang Qian , Jia An , Liu Xizi , Han Shiyi , Fan Siyang
Published: April 2021

A new sesquiterpene, chlorantholide G (1), a new sesquiterpene dimer, elatiolactone (2), and 2 new diterpenes, elatiorlabdane B (3) and elatiorlabdane C (4), together with 51 known compounds, were isolated from the aerial parts of Chloranthus elatior. The new structures including their absolute configurations were mainly established by mass spectrometric, NMR, and electronic circular dichroism experiments. All isolated compounds were tested for their anti-hDHODH activity. (4S,6R)-4-hydroxy-6-isopropyl-3-methylcyclohex-2-enone (5) and (4S,5R,9S,10R)-8(17),12,14-labdatrien-18-oic acid (29) were the most active compounds with IC50 values of 18.7 and 30.7 µM, respectively.
Low Piperine Fractional Piper nigrum Extract Enhanced the Antitumor Immunity via Regulating the Th1/Th2/Treg Cell Subsets on NMU-Induced Tumorigenesis Rats
Authors: Saetang Jirakrit , Tedasen Aman , Sangkhathat Surasak , Sangkaew Natnaree , Dokduang Sirinapa , Prompat Napat , Taraporn Siriporn , Graidist Potchanapond
Published: April 2021

Cancer is one of the major causes of death worldwide. In addition to standard regimens, tumor suppression ability has been demonstrated in many types of natural products, including Piper nigrum, or black pepper. In previous reports, we demonstrated the antitumor effect of low piperine fractional Piper nigrum extract in vitro and in vivo. However, the effects of low piperine fractional P. nigrum extract in the aspect of antitumor immunity has not yet been investigated. In this study, tumor-bearing rats were fed with 100 mg/kg BW or 200 mg/kg BW of low piperine fractional P. nigrum extract 3 times per week for 4 weeks. Tumor burden and hematological data were then evaluated. Immunological data was investigated using a cytokine array and flow cytometry. The results showed that both doses of low piperine fractional P. nigrum extract significantly suppressed tumor progression in N-nitrosomethylurea-induced mammary tumor rats.
There were no significant changes observed in the total white blood cells, red blood cells, and hemoglobin. Low piperine fractional P. nigrum extract suppressed some cytokine and chemokine levels including CXCL7, sICAM-1, and L-selectin 0.2- to 0.6-fold. Interestingly, 200 mg/kg BW of low piperine fractional P. nigrum extract significantly promoted type 1 T helper cell, and suppressed neutrophil, basophil, type 2 T helper cell, and regulatory T cell compared to the control group. In summary, these results indicate that low piperine fractional P. nigrum extract had a high efficacy in supporting antitumor activity at immunological levels via regulating Th1/Th2/Treg cells.
Diterpenes from Euphorbia myrsinites and Their Anti-inflammatory Property
Authors: Grauso Laura , de Falco Bruna , Lucariello Giuseppe , Capasso Raffaele , Lanzotti Virginia
Published: April 2021

Euphorbia myrsinites is one of the oldest spurges described and used in folk medicine. It is characterized by blue-grey stems similar to myrtle, and it is spread in the Mediterranean region, Asia, and the USA. Chemical analysis of E. myrsinites collected in Turkey afforded the isolation of 4 diterpenes based on the so-called myrsinane skeleton being tetraesters of the tetracyclic diterpene alcohol myrsinol. In this study, the phytochemical analysis of this species collected in Italy has been undertaken to afford the isolation of a new atisane diterpene, named myrsatisane, 3 ingenol derivatives, along with the 4 tetraester derivatives previously found. A triterpene compound based on the euphane skeleton has also been isolated. Structural elucidation of the new myrsatisane was based on spectroscopic techniques, including HR-MS and 1- and 2-dimensional NMR experiments. Its relative configuration was determined by NOE correlations, while absolute
stereochemistry was obtained by quantum-mechanical DFT studies. While diterpenes with the atisane skeleton are relatively common in Euphorbia species, this is the first report of an atisane diterpene from E. myrsinites. All the isolated terpenes were tested for anti-inflammatory activity on J774A.1 macrophages stimulated with lipopolysaccharide by evaluation of nitrite and pro-inflammatory cytokine Il-1β levels. Among tested compounds, the 3 ingenol diterpenes exhibited a dose-dependent (0.001 – 3 µM) significant activity, thus showing their potential as anti-inflammatory drug candidates.
Recent Advances and the Prospect of Hypervalent Iodine Chemistry
Authors: Zhang Chi , Yang Xiao-Guang , Hu Ze-Nan , Jia Meng-Cheng , Du Feng-Huan
Published: April 2021

Nowadays, hypervalent iodine chemistry has remarkably advanced in parallel with the emergence of novel hypervalent iodine reagents. Hypervalent iodine reagents, due to their outstanding characteristics including rich reactivities, excellent chemoselectivity, stability, and environmental friendliness, are becoming more and more popular in the synthetic organic chemistry. In this Account, a number of recent elegant research works and our perspective on the future of hypervalent iodine chemistry is presented.

1 Introduction

2 Recent Advances and Discussion

2.1 Novel Reactivities of Hypervalent Iodine Reagents

2.2 Atom-Economical Reactions Promoted by Hypervalent Iodine Reagents

2.3 Other Applications of Hypervalent Iodine Reagents

2.4 The Applications of DFT Calculations in Elucidating Reaction Mechanism Involving Hypervalent Iodine Reagents

3 Outlook and Conclusion
Heterocycle–Heterocycle Strategy for 4,5-Disubstituted Pyrrolidine 2,3-Diones: Reductive Rearrangement Approach from Isoxazole Esters
Authors: Lal Mukul , Kamath Prashantha , Jadhav Vaibhav
Published: April 2021

The work demonstrates the heterocycle–heterocycle interconversion strategy to access 4,5-disubstituted 3-hydroxy-2-pyrrolidinone in moderate to good yields (50–80%). The approach has a distinct advantage over a multicomponent reaction approach as it allows access to unsubstituted 3-hydroxy-2-pyrrolidinone at the nitrogen position for further functionalization.
π-Extended Ladder-Type Conjugated Polymers via BN-Annulation
Authors: Qiang Peirong , Sun Zuobang , Xue Bai , Zhang Fan
Published: April 2021

Two kinds of ladder-type conjugated polymers were concisely synthesized by the formation of single-stranded conjugated polymers via Stille cross-couplings, followed by nitrogen-directed electrophilic borylations at electron-rich aromatic rings. The resulting BN-annulated polymers show good film-forming behaviors and high air and thermal stability. Their structurally shape-persistent rigid backbones render them with π-extended conjugation, allowing for efficient light harvesting in the low-energy regions, and emitting strong fluorescence with narrow emission widths.
Single-Component Organic Solar Cells with Competitive Performance
Authors: He Yakun , Li Ning , Brabec Christoph J.
Published: April 2021

Organic semiconductors with chemically linked donor and acceptor units can realize charge carrier generation, dissociation and transport within one molecular architecture. These covalently bonded chemical structures enable single-component organic solar cells (SCOSCs) most recently to start showing specific advantages over binary or multi-component bulk heterojunction concepts due to simplified device fabrication and a dramatically improved microstructure stability. The organic semiconductors used in SCOSCs can be divided into polymeric materials, that is, double-cable polymers, di-block copolymers as well as donor–acceptor small molecules. The nature of donor and acceptor segments, the length and flexibility of the connecting linker and the resultant nanophase separation morphology are the levers which allow optimizing the photovoltaic performance of SCOSCs. While remaining at 1–2% for over a decade, efficiencies of SCOSCs have recently witnessed significant improvement to over 6% for several materials systems and to a record efficiency of 8.4%. In this mini-review, we summarize the recent progress in developing SCOSCs towards high efficiency and stability, and analyze the potential directions for pushing SCOSCs to the next efficiency milestone.
External electric field and strain effects in a quantum paramagnet
Authors: Zvyagin A. A.
Published: April 2021

Influence of the external electric field and the external strain on a quantum paramagnetic insulator is studied. It is shown that the external electric field and/or strain can cause drastic changes in the magnetic characteristics of the paramagnet.
Chiral tunneling through the single barrier structure based on the α-T3 model
Authors: Korol A. M. , Sokolenko A. I. , Shevchenko O.
Published: April 2021

The transmission coefficient T of the Dirac quasielectrons through a rectangular potential barrier in the α-T3 model is calculated and analyzed in the continuum approach. The dependence of the transmission rate on para-meter α, which characterizes the degree of coupling of the central atom with the atoms in the vertices of the hexagonal lattice, and parameter β, which is equal to the ratio of Fermi velocities in the barrier and out-of-barrier regions, is analyzed. It was found, for certain quasiparticle energies, the supertunneling phenomenon is observed, which is that the transmission coefficient is equal to one independently of an angle of the particle incidence on the barrier, provided that α = 1. The values of these energies depend on the barrier height and the parameter β. It is shown that for some sets of parameters the function T(α) has maxima in the range 0 < α < 1. For a large range of parameter values, the transmittance increases monotonically with increasing α. For the zero angle of incidence of quasiparticles on the barrier the Klein paradox is observed, i.e., the quantum transparency of the system is ideal, and this is true for any values of parameters α, β, barrier height, and energy of quasiparticles.
Long-term stability of TVO low-temperature sensors before and after gamma irradiation with a high dose
Authors: Filippov Yu. P. , Miklyaev V. M. , Vainberg V. V.
Published: April 2021

The long-term stability of well-known TVO sensors before and after gamma irradiation was investigated during almost 17 years. Five of six sensors, calibrated in the temperature range from 3 to 300 K, were selected according to a requirement of their relative accuracy ΔT/T ≤ ± 0.25% at the cryogenic temperature range. Long-term stability measurements made 7.5 years after calibration are in good agreement with this value at 293, 77.3, and 4.2 K. Then these sensors and the sixth sensor, taken as the “worst” one for comparison, were irradiated by the 60Co gamma source at room temperature up to the total dose of about 1 MGy. Noticeable relative temperature shifts (more than ± 0.25%) are revealed for all the sensors after irradiation, and this fact is explained based on the model of structural changes in the volume of the sensitive element. Post-irradiation measurements carried out during 9 years at 293, 77.3, and 4.2 K indicate good stability of the sensors after irradiation.
Conformational composition of 1-butanol in matrix isolation
Authors: Doroshenko I. , Vaskivsky Ye. , Chernolevskaya Ye. , Doroshenko O.
Published: April 2021

IR absorption spectra of 1-butanol isolated in an argon matrix were obtained at temperatures from 10 to 50 K. The conformational behavior of 1-butanol was analyzed using the results of quantum-chemical simulation of the structure and vibrational spectra of its small clusters. We studied the conformational composition of 1-butanol in matrix isolation and showed the transformation of its structure that occurs with an increase in the matrix temperature.
Low-temperature secondary emission mass spectrometric investigations of a condensed-phase environment of biologically significant compounds
Authors: Kosevich Marina V. , Boryak Oleg A. , Shelkovsky Vadim S.
Published: April 2021

The main features of the secondary emission mass spectrometry probing of condensed systems containing compounds of biological significance at low temperatures are summarized. The possibilities of distinguishing mass spectra of the solid and liquid phases of simple organic compounds and water as the medium for bio-molecules, monitoring of phase transitions and nonequilibrium processes are illustrated. The peculiarities of a model of sputtering of metastable liquids are described. On the basis of the evaluation of these findings, an idea concerning the probable source of relatively large clusters of organic molecules and ions emerging on sputtering of the liquid phase of organic matter condensed on dust grains in space is proposed and discussed.
Four microphones track a flying drone
Authors: Yiu Yuen
Published: April 2021

The set of mics could detect and track a buzzing drone from almost up to a quarter mile away.
Barocalorics emerging as an environmentally friendly alternative to greenhouse gas producing refrigerants
Authors: Frank Jodi Ackerman
Published: April 2021

Opportunities to tune the many different materials that exhibit the barocaloric effect could make them more competitive as a refrigerant replacement.
Quirk of microswimmer propellers found to enable bimodal swimming and different applications
Authors: Johnson-Groh Mara
Published: April 2021

A unique microswimmer uses dumbbell-shaped propellers for bidirectional movement, enabling application for the technology in cargo transportation and swarm control.
Carbon nanotube thermoelectric devices by direct printing: Toward wearable energy converters
Authors: Lee Hye Ryoung , Furukawa Naoki , Ricco Antonio J. , Pop Eric , Cui Yi , Nishi Yoshio
Published: April 2021

Thermoelectric devices convert thermal energy to electrical energy and are particularly well-suited for energy harvesting from waste heat. Even as the number of electronic devices used in daily life proliferates, technical advances diminish the average power such devices require to perform a given function. Localized thermal gradients that abound in our living environments, despite having modest energy densities, are therefore becoming increasingly viable and attractive to power such devices. With this motivation, we report the design, fabrication, and characterization of single-wall carbon nanotube thermoelectric devices (CNT-TDs) on flexible polyimide substrates as a basis for wearable energy converters. Our aqueous-solution-based film fabrication process could enable readily scalable, low-cost TDs; here, we demonstrate CNT-hydroxypropyl cellulose (HPC) composite thermoelectric films by aerosol jet printing. The electrical conductivity of the composite films is controlled through the number of CNT/HPC layers printed in combination with control of the annealing conditions. The HPC initially disperses the CNTs in deionized water, the greenest of solvents, and is subsequently partially eliminated from the film by annealing, with concomitant morphological changes that we characterized by TEM. HPC removal is key to obtaining good electrical conductivity (0.94 to 1.10 × 105 S/m) and Seebeck coefficients (36 to 43 μV/K). We also report a power factor of 208 μW m−1 K−2 for a CNT-TD composed of 15 layers of CNT/HPC, promising performance for CNT-based flexible TDs that are deposited from aqueous solution, stable in air, and require no additional doping or sorting processes.
Hybrid Bessel beam and metamaterial lenses for deep laparoscopic nondestructive evaluation
Authors: Ahmed Hossain , Ghosh Susanta , Sain Trisha , Banerjee Sourav
Published: April 2021

A unique non-diffracting hybrid order longitudinal Bessel beam with pronounced resilience to scattering using acoustic metamaterial, which we call hybrid Bessel beams (HYBEs), is currently unknown. Newly proposed hybrid Bessel beams are different than the conventional cross-sectional Bessel beams. In this article, we explain the physics of multifunctional ultrasonic capabilities of a bioinspired interlocking architecture of acoustic metamaterial. At first, for the newly proposed metastructure, understanding the physics and wave energy is predictively focused through attenuative surfaces at various ultrasonic frequencies (∼120 to ∼130 kHz). Finally, a zero-order first of its kind ultrasonic Bessel-like beam between frequencies of ∼265 and ∼272 kHz is shown propagating a long distance through the base material. The new propagation had minimal reduction in energy amplitude, while the displacement was nearly constant across the depth of the wave guide following a second-order Bessel function of the first kind. To explain the physics of the phenomena, mode shapes in the frequency-wavenumber domain are investigated. Furthermore, identification of the propagating wave vector using equi-frequency contours at multiple ranges confirmed the presence of the proposed acoustic features. These abilities of the proposed metamaterial have key advantages to propagate waves deeper into thick attenuative and aberrative structures such as brain tissue, soft skin and muscles, paint surface, and non-accessible composite materials. We envision potential applications of the proposed HYBE for the non-destructive evaluation (NDE) of attenuative materials that are not easily accessible for testing. To verify the wave focusing and long-distance wave propagation, an ad hoc metamaterial lens for the conventional NDE transducer is proposed, which demonstrated wave propagation through a 10 mm thick carbon fiber reinforced polymer composite structure.
Multi-chord IR–visible two-color interferometer on KSTAR
Authors: Juhn June-Woo , Lee K. C. , Lee T. G. , Wi H. M. , Kim Y. S. , Hahn S. H. , Nam Y. U.
Published: April 2021

Major parts of an IR–visible two-color interferometer (TCI) on KSTAR have been upgraded for the multi-chord operation: (1) a diode-pumped-solid-state (DPSS) laser (660 nm) replacing the former HeNe laser (633 nm), (2) vacuum-compatible vibration isolator with titanium retro-reflectors, and (3) full digital phase comparator for multi-chord real-time density signals. The commercial compact DPSS laser suits the multiple chord configuration with its strong beam power (500 mW) and long coherent length (>100 m). Ti retro-reflectors are mounted on vacuum-compatible vibration isolators. The isolators are essential for the visible beams to avoid any fringe skips due to their short wavelength, considering the speed of the mechanical vibration (up to hundreds of μm). Field-programmable-gate-array (FPGA) modules count the entire fringes fast enough with a signal output rate up to 1.25 MHz, solving the fringe skip issues. The FPGA module enables the full digital processing of the phase comparator with a CORDIC algorithm after the sampling rate of 160 MS/s for the 40 MHz intermediate frequency of each beam. The full digital signals are transferred to the main plasma control system in real-time. Stable single-input-single-output operation of the KSTAR density control was demonstrated with the TCI. The real-time density profile control is also promising in the near future, with multiple actuators such as pellets and gas puffings.
Droplet hurdles race
Authors: de Maleprade Hélène , Bendimerad Rafid , Clanet Christophe , Quéré David
Published: April 2021

Water is extremely mobile on non-wetting surfaces, on which it glides at high velocities. We discuss how a few indentations placed on the surface markedly slow down drops forced to hit and jump above these hurdles. The corresponding “friction” is characterized and shown to be inertial in nature, which we interpret as the result of the successive soft shocks of the drops against obstacles.
Numerical convergence of volume of fluid based large eddy simulations of atomizing sprays
Authors: Abbas F. , Wang B. , Cleary M. J. , Masri A. R.
Published: April 2021

This paper presents three volume of fluid (VoF)-based methods for large eddy simulations of atomizing sprays with different treatments of the unresolved interface. The turbulent filtered VoF model uses conventional turbulent viscosity models to close the combined interfacial and turbulent sub-grid fluctuations. The hybrid turbulence filtering and artificial compression model includes an additional artificial compression term that is applied along regions where the liquid–air interface is continuous, while conventional turbulence filtering is activated in regions with discrete liquid objects. The new explicit volume diffusion model (EVD) is based on the concept of averaging the VoF equations over explicitly defined physical volumes that are independent of the numerical grid. Closure models of the sub-volume flux and stress terms introduce explicit volume diffusion and explicit volume viscosity that are physically defined and linked to the volume size. Numerical convergence is achieved by reducing the grid size while keeping the explicit volume size constant. The models are tested for two experimental atomizing spray cases with different Weber numbers. The superior numerical convergence of the EVD model is demonstrated by analysis of the mean and rms of the volume fraction and velocity fields. Two models for the surface tension force are investigated for the EVD simulations. Compared with the simple surface tension model which neglects sub-grid fluctuations, an improved volume-averaged model based on fractal properties of wrinkled sub-volume interfaces gives better predictions of the mean volume fraction relative to the experimental data but requires selection of a model constant.
A dislocation-based dynamic strength model for tantalum across a large range of strain rates
Authors: Kositski Roman , Mordehai Dan
Published: April 2021

We present a dislocation-based strength model for tantalum that captures the plastic deformation at high strain rates above 103s−1. The model has its origins in molecular dynamic simulations and it is implemented in a 3D continuum framework. We calibrate and validate the model using Split Hopkinson Pressure Bar, plate impact, and Richtmyer–Meshkov instability experiments. With the validated model, we can computationally generate stress–strain curves at strain rates of 103−107s−1 for samples with various initial dislocation densities. Based on the results, we show that the dynamic yield strength of annealed tantalum at high strain rates is followed by softening since mobile dislocation densities rapidly increase due to the high shear stress. This strain-softening is evident only at the high strain rate regime and it is much less pronounced in cold-worked Ta.
Upscaling of multi-beam x-ray ptychography for efficient x-ray microscopy with high resolution and large field of view
Authors: Wittwer Felix , Lyubomirskiy Mikhail , Koch Frieder , Kahnt Maik , Seyrich Martin , Garrevoet Jan , David Christian , Schroer Christian G.
Published: April 2021

Nondestructive imaging with both a large field of view and a high spatial resolution is crucial to understand complex materials and processes in science and technology. X-ray ptychography can provide highest spatial resolution but is limited in the field of view by the acquisition time and coherent flux at modern x-ray sources. By multi-beam ptychography, the sample can be imaged in parallel by several spatially separated and mutually incoherent beams. We have implemented this method using 3D nanoprinted x-ray optics to create tailor-made x-ray multi-beam arrays. The use of 3D printing allows us to create focusing optics with a minimum of nonfunctional support structures. In this way, large sample areas can be efficiently scanned in parallel with up to six illuminating beams.
Carbon-dioxide absorption spectroscopy with solar photon counting and integrated lithium niobate micro-ring resonator
Authors: Zhang Jiuyi , Sua Yong Meng , Chen Jia-Yang , Ramanathan Jeevanandha , Tang Chao , Li Zhan , Hu Yongxiang , Huang Yu-Ping
Published: April 2021

We demonstrate a spectroscope using single-photon counters and a chip-integrated lithium niobate micro-ring filter to measure the atmospheric CO2 absorption spectrum passively. By thermo-optically sweeping the filter over 150 pm and referencing the resulting photon counts to a bypass channel, we sample the absorption spectrum at an ultrahigh-resolution of 6 pm. Incorporating it into a ground-based field system, we characterize the CO2 absorption through the atmosphere by counting the solar photons across the absorption line around 1572.02 nm, which agrees well with its transmission spectrum at standard atmospheric pressure. Our results highlight the potential of adopting integrated photonics and single-photon counting in remote sensing systems for high detection sensitivity, superior resolution, and significantly reduced size, weight, and power.