bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural Insights into Catalytic Versatility of the Flavin-dependent Hydroxylase (HpaB) from Escherichia coli
Authors: Shen Xiaolin , Zhou Dayong , Lin Yuheng , Wang Jia , Gao Shuaihua , Kandavelu Palani , Zhang Hua , Zhang Ruihua , Wang Bi-Cheng , Rose John , Yuan Qipeng , Yan Yajun
Published: May 2019

4-Hydroxyphenylacetate 3-hydroxylase (EcHpaB) from Escherichia coli is capable of efficient ortho-hydroxylation of a wide range of phenolic compounds and demonstrates great potential for broad chemoenzymatic applications. To understand the structural and mechanistic basis of its catalytic versatility, we elucidated the crystal structure of EcHpaB by X-ray crystallography, which revealed a unique loop structure covering the active site. We further performed mutagenesis studies of this loop to probe its role in substrate specificity and catalytic activity. Our results not only showed the loop has great plasticity and strong tolerance towards extensive mutagenesis, but also suggested a flexible loop that enables the entrance and stable binding of substrates into the active site is the key factor to the enzyme catalytic versatility. These findings lay the groundwork for editing the loop sequence and structure for generation of EcHpaB mutants with improved performance for broader laboratory and industrial use.
Extending the depth-of-field of imaging systems with a scattering diffuser
Authors: Liao Meihua , Lu Dajiang , Pedrini Giancarlo , Osten Wolfgang , Situ Guohai , He Wenqi , Peng Xiang
Published: May 2019

Large depth of field (DOF) is a longstanding goal in optical imaging field. In this paper we presented a simple but efficient method to extend the DOF of a diffraction-limited imaging system using a thin scattering diffuser. The DOF characteristic of the imaging system with random phase modulation was analyzed based on the analytical model of ambiguity function as a polar display of the optical transfer function (OTF). The results of numerical simulation showed that more high-frequency components existed in the defocused OTF curve when the exit pupil of the imaging system exhibited a random phase modulation. It proved the important role of the scattering diffuser in extending the DOF of imaging systems. For the reconstruction, a stack of point spread functions (PSFs) corresponding to different axial locations within a measurement range were superimposed to construct the stacked PSF. Then the large DOF image was recovered from a speckle pattern by deconvolution. In this proof-of-concept, we experimentally demonstrated the single-shot imaging with larger DOF using a thin glass scattering diffuser in both a single-lens imaging system and a microscopic imaging system.
A Novel 3D In Vitro Platform for Pre-Clinical Investigations in Drug Testing, Gene Therapy, and Immuno-oncology
Authors: Candini Olivia , Grisendi Giulia , Foppiani Elisabetta Manuela , Brogli Matteo , Aramini Beatrice , Masciale Valentina , Spano Carlotta , Petrachi Tiziana , Veronesi Elena , Conte Pierfranco , Mari Giorgio , Dominici Massimo
Published: May 2019

Tumors develop within complex cell-to-cell interactions, with accessory cells playing a relevant role starting in the early phases of cancer progression. This event occurs in a three-dimensional (3D) environment, which to date, has been difficult to reproduce in vitro due to its complexity. While bi-dimensional cultures have generated substantial data, there is a progressive awareness that 3D culture strategies may rapidly increase the understanding of tumor development and be used in anti-cancer compound screening and for predicting response to new drugs utilizing personalized approaches. However, simple systems capable of rapidly rebuilding cancer tissues ex-vivo in 3D are needed and could be used for a variety of applications. Therefore, we developed a flat, handheld and versatile 3D cell culture bioreactor that can be loaded with tumor and/or normal cells in combination which can be monitored using a variety of read-outs. This biocompatible device sustained 3D growth of tumor cell lines representative of various cancers, such as pancreatic and breast adenocarcinoma, sarcoma, and glioblastoma. The cells repopulated the thin matrix which was completely separated from the outer space by two gas-permeable membranes and was monitored in real-time using both microscopy and luminometry, even after transportation. The device was tested in 3D cytotoxicity assays to investigate the anti-cancer potential of chemotherapy, biologic agents, and cell-based therapy in co-cultures. The addition of luciferase in target cancer cells is suitable for comparative studies that may also involve parallel in vivo investigations. Notably, the system was challenged using primary tumor cells harvested from lung cancer patients as an innovative predictive functional assay for cancer responsiveness to checkpoint inhibitors, such as nivolumab. This bioreactor has several novel features in the 3D-culture field of research, representing a valid tool useful for cancer investigations, drug screenings, and other toxicology approaches.
A Bio-inspired Hypoxia Sensor using HIF1a-Oxygen-Dependent Degradation Domain
Authors: Iglesias Pablo , Penas Cristina , Barral-Cagiao Laura , Pazos Elena , Costoya Jose A.
Published: May 2019

Functional imaging has become an important tool in oncology because it not only provides information about the size and localization of the tumour, but also about the pathophysiological features of the tumoural cells. One of the characteristic features of some tumour types is that their fast growth leads to deficient intratumoral vascularization, which results in low oxygen availability. To overcome this lack of oxygen, tumoural cells activate the neoangiogenic program by upregulating the transcription factor HIF-1α. Herein we report a non-invasive in vitro detection method of hypoxia using designed fluorescent peptide probes based on the oxygen-dependent degradation domain of HIF-1α. The fluorescent probe retains the oxygen-sensing capability of HIF-1α, so that it is stabilized under hypoxia and readily degraded by the proteasome under normoxia, thus providing direct information of the cellular oxygen availability.
Nanoparticle-Infused UHMWPE Layer as Multifunctional Coating for High-Performance PPTA Single Fibers
Authors: Zhang Zhuolei , Zhao Yao , Li Haoqi , Percec Simona , Yin Jie , Ren Fei
Published: May 2019

High-performance fibers made of poly-(p-phenylene terephthalamide) (PPTA) with high stiffness and high strength are widely used in body armor for protection due to their high degree of molecular chain alignment along the fiber direction. However, their poor mechanical properties in the transverse direction and low surface friction are undesirable for applications requiring resistance to ballistic impact. Here we provide a simple yet effective surface engineering strategy to improve both the transverse mechanical properties and the tribological property by coating PPTA fibers with ultra-high molecular weight polyethylene (UHMWPE) embedded with silica nanoparticles. The coated-PPTA fiber shows remarkable enhancement in transverse mechanical properties including ~127% increase of Young’s modulus, which is attributed to both the alignment of UHMWPE chains in the transverse direction and the embeded ceramic nanoparticles. Meanwhile, the surface friction of the coated fiber increases twofold as a result of the ceramic nanoparticles. In addition, the coated fibers exhibit an enhanced chemical resistance to external harsh environment. The improved transverse mechanical properties, surface frictional characteristics, and chemical resistance demonstrate that coating with UHMWPE and ceramic nanoparticles can be used as an effective approach to enhance the performance of PPTA and other high-performance polymer fibers for body armor applications.
Mesenchymal stem cells of Systemic Sclerosis patients, derived from different sources, show a profibrotic microRNA profiling
Authors: Di Benedetto Paola , Panzera Noemi , Cipriani Paola , Mastroiaco Valentina , Tessitore Alessandra , Liakouli Vasiliki , Ruscitti Piero , Berardicurti Onorina , Carubbi Francesco , Guggino Giuliana , Bianchi Andrea , Di Marco Antinisca , Ciccia Francesco , Alesse Edoardo , Giacomelli Roberto
Published: May 2019

Systemic Sclerosis (SSc) is a disease with limited therapeutic possibilities. Mesenchymal stem cells (MSCs)-therapy could be a promising therapeutic option, however the ideal MSCs source has not yet been found. To address this problem, we perform comparison between bone marrow (BM)-MSCs and adipose (A)-MSCs, by the miRs expression profile, to identify the gene modulation in these two MSCs source. MicroRNAs (miRs) are RNAs sequences, regulating gene expression and MSCs, derived from different tissues, may differently respond to the SSc microenvironment. The miRs array was used for the miRs profiling and by DIANA-mirPath tool we identified the biological functions of the dysregulated miRs. In SSc-BM-MSCs, 6 miRs were significantly down-regulated and 4 miRs up-regulated. In SSc-A-MSCs, 11 miRs were significantly down-regulated and 3 miRs up-regulated. Interestingly, in both the sources, the involved pathways included the senescence mechanisms and the pro-fibrotic behaviour. Furthermore, both the MSCs sources showed potential compensatory ability. A deeper knowledge of this miRs signature might give more information about some pathogenic steps of the disease and in the same time clarify the possible therapeutic role of autologous MSCs in the regenerative therapy in SSc.
Time-dependent prediction of arrhythmia recurrences during long-term follow-up in patients undergoing catheter ablation of atrial fibrillation: The Leipzig Heart Center AF Ablation Registry
Authors: Kornej Jelena , Schumacher Katja , Zeynalova Samira , Sommer Philipp , Arya Arash , Weiß Manuela , Piorkowski Christopher , Husser Daniela , Bollmann Andreas , Lip Gregory Y. H. , Hindricks Gerhard
Published: May 2019

The prediction of arrhythmia recurrences after catheter ablation of atrial fibrillation (AF) remains challenging. The aim of current analysis was to investigate the time-dependent prediction of arrhythmia recurrences after AF catheter ablation during long-term follow-up. The study included 879 patients (61 ± 10 years; 64% males; 39% persistent AF) undergoing first AF catheter ablation. Rhythm outcomes were documented using 7-days Holter monitoring. The APPLE score (Age, Persistent AF, imPaired eGFR, Left atrium (LA), EF) was calculated at baseline, while MB-LATER score (Male gender, Bundle branch block, LA, AF Type, Early Recurrences) 3 months after ablation. The median follow-up time was 37 months [95%CI 35;39]. ERAF and LRAF occurred in 45% and 64%, respectively. On multivariable analysis, ERAF (HR 2.095, 95%CI 1.762–2.490, p < 0.001) was strongly associated with LRAF. The APPLE (HR 1.385, 95%CI 1.276–1.505, p < 0.001) and MB-LATER (HR 1.326, 95%CI 1.239–1.419, p < 0.001) scores significantly predicted LRAF during follow-up. On the ROC analysis, APPLE (AUC 0.640, 95%CI 0.602–0.677, p < 0.001) and MB-LATER (AUC 0.654, 95%CI 0.616–0.691, p < 0.001) demonstrated moderate prediction. Summarizing, ERAF was the strongest predictor for LRAF in time-dependent manner. The APPLE and MB-LATER scores demonstrated moderate prediction of arrhythmia recurrences during long term follow-up.
Formation and stability of complex metallic phases including quasicrystals explored through combinatorial methods
Authors: Wolf Witor , Kube Sebastian A. , Sohn Sungwoo , Xie Yujun , Cha Judy J. , Scanley B. Ellen , Kiminami Claudio S. , Bolfarini Claudemiro , Botta Walter J. , Schroers Jan
Published: May 2019

Aluminum-based quasicrystals typically form across narrow composition ranges within binary to quaternary alloys, which makes their fabrication and characterization challenging. Here, we use combinatorial approaches together with fast characterization techniques to study a wide compositional range including known quasicrystal forming compositions. Specifically, we use magnetron co-sputtering to fabricate libraries of ~140 Al-Cu-Fe and ~300 Al-Cu-Fe-Cr alloys. The alloys compositions are measured through automated energy dispersive X-ray spectroscopy. Phase formation and thermal stability are investigated for different thermal processing conditions (as-sputtered and annealed at 400 °C, 520 °C and 600 °C for Al-Cu-Fe libraries; annealed at 600 °C for Al-Cu-Fe-Cr libraries) using automated X-ray diffraction and transmission electron microscopy. In both systems the compositional regions across which the quasicrystalline phase forms are identified. In particular, we demonstrate that the quasicrystalline phase forms across an unusually broad composition range in the Al-Cu-Fe-Cr system. Additionally, some of the considered alloys vitrify during sputtering, which also allows us to study their nucleation behavior. We find that phases with polytetrahedral symmetry, such as the icosahedral quasicrystal and the λ-Al13Fe4 phase, exhibit higher nucleation rates but lower growth rates, as compared to other phases with a lower degree of polytetrahedral order. Altogether, the here used combinatorial approach is powerful to identify compositional regions of quasicrystals.
Differential microRNA profile underlies the divergent healing responses in skin and oral mucosal wounds
Authors: Simões Alyne , Chen Lin , Chen Zujian , Zhao Yan , Gao Shang , Marucha Phillip T. , Dai Yang , DiPietro Luisa A. , Zhou Xiaofeng
Published: May 2019

Oral mucosal wounds heal faster than skin wounds, yet the role of microRNAs in this differential healing has never been examined. To delineate the role of microRNAs in this site-specific injury response, we first compared the microRNAome of uninjured skin and oral mucosa in mice. A total of 53 tissue-specific microRNAs for skin and oral mucosa epithelium were identified. The most striking difference was the high abundance of miR-10a/b in skin (accounting for 21.10% of the skin microRNAome) as compared to their low expression in oral mucosa (2.87%). We further examined the dynamic changes of microRNAome throughout the time course of skin and oral mucosal wound healing. More differentially expressed microRNAs were identified in skin wounds than oral wounds (200 and 33, respectively). More specifically, miR-10a/b was significantly down-regulated in skin but not oral wounds. In contrast, up-regulation of miR-21 was observed in both skin and oral wounds. The therapeutic potential of miR-10b and miR-21 in accelerating wound closure was demonstrated in in vitro assays and in a murine skin wound model. Thus, we provided the first site-specific microRNA profile of skin and oral mucosal wound healing, and demonstrate the feasibility of a microRNA-based therapy for promoting wound closure.
Selective Particle Filtering in a Large Acoustophoretic Serpentine Channel
Authors: Kandemir M. H. , Wagterveld R. M. , Yntema D. R. , Keesman K. J.
Published: May 2019

The objective of this study is to investigate the performance of a serpentine channel for acoustically driven selective particle filtering. The channel consists of sharp corners and straight sections, and the acoustic field is affecting the particles throughout the channel. A prototype of the separator channel is manufactured using 3D printing. Acoustic waves are generated by a piezoelectric transducer operating near 2 MHz. Computer simulations are carried out to explore and visualize the flow field and acoustic field in the separator. Selective particle trapping is aimed to be achieved in the hairpin sections, which is confirmed by experiments. Spherical polyethylene particles of 34 µm, 70 µm and 100 µm diameter are used to demonstrate selective trapping by adjusting the flow rate in the channel or voltage input to the transducer. In addition, wheat beer containing yeast up to 20 µm size is selectively filtered by adjusting the flow rate to the channel. Experiments demonstrate that selective particle filtering is possible in the serpentine channel as both methods yield clear separation thresholds.
Direct-acting oral anticoagulants (DOACs) in pregnancy: new insight from VigiBase®
Authors: Sessa Maurizio , Mascolo Annamaria , Callréus Torbjörn , Capuano Annalisa , Rossi Francesco , Andersen Morten
Published: May 2019

We aimed to perform an analysis of individual case safety reports retrieved after the Standardized MedDRA Query “Pregnancy and neonatal topics” for which Direct-Acting Oral Anticoagulants (DOACs) were claimed as suspected/interacting drugs. Additionally, to investigate if exists a disproportion of cases reporting “Pregnancy and neonatal topics” adverse events rather than other adverse events for DOACs in comparison with all other drugs registered in VigiBase or warfarin. VigiBase, the World Health Organization (WHO)’s global database of individual case safety reports was used as data source. Forty-two cases of abortion were detected of which 18 (42.8%) had alternative causes for its occurrence. Fourteen cases reported congenital anomaly (8 cases) or low birth weight baby/fetal growth restriction (6 cases) of which 62.5% and 33.3% had at least one confounder, respectively. In the disproportionality analyses, a potential safety signal for spontaneous abortion emerged for rivaroxaban (Reporting Odds Ratio, ROR 2.70; 95% CI 1.79–4.07) and apixaban (ROR 6.76; 95% CI 2.99–15.25). However, when the same analyses were performed using only cases without alternative causes, no statistically significant associations for rivaroxaban when compared to all other drugs (ROR 1.05; 95% CI 0.54–2.02) or warfarin (ROR 0.79; 95% CI 0.47–1.32) were found. For apixaban, we found a statistically significant ROR for induced abortion when compared to all other drugs or warfarin. For the majority of cases claiming DOACs-induced teratogenic effects, spontaneous or induced abortion there was at least one alternative cause explaining the occurrence of the adverse events. For rivaroxaban, when cases without confounders were considered, no safety signals emerged. However, for apixaban, we found a potential safety signal suggesting an increased probability of reporting spontaneous/induced abortion rather than other events when compared to all other drugs or warfarin.
Metal–Organic-framework Nanoparticles: Synthesis, Characterization and Catalytic Applications
Authors: Jena H. S. , Leus K. , Van Der Voort P.
Published: May 2019

In this chapter, the synthesis, characterization and catalytic applications of metal organic framework nanoparticles (MOF-NPs) are discussed. This chapter begins with a general introduction, then the synthesis and characterization methods of MOFs and MOF-NPs are discussed, as well as the catalytic applications of MOF-NPs. The focus is set on design strategies for the synthesis of MOF-NPs, in conjunction with characterization techniques and recent progress in the synthesis of advanced MOF-NPs, such as base metal NPs, multi-metallic nanoparticles and NPs with a core–shell structure. Regarding the catalytic applications of MOF-NPs, oxidation, hydrogenation, coupling reactions (C–C, A3-type and cascade) and asymmetric synthesis are discussed. Finally, the importance of how to control the shape, size and location of NPs is stressed in order to better understand their reactivity.
Nanoparticle Design for the Catalytic Valorization of Lignocellulosic Biomass
Authors: Chen Xi , Yan Ning
Published: May 2019

In this chapter, an account of up-to-date developments in the catalytic valorisation of lignocellulosic biomass via the novel design of nanocatalysts is given. Lignocellulosic biomass represents the largest renewable carbon resource that is used to produce value-added chemicals. Nanocatalysts, tuneable in size, shape, composition, and support, have been widely employed in lignocellulosic biomass valorisation, in order to simultaneously improve the conversion and product selectivity, and to allow the use of milder reaction conditions. The synthesis, design and applications of nanocatalysts for the transformation of cellulose (glucose and cellulose), hemicellulose (xylose, xylan and hemicellulose) and lignin (lignin model compounds and lignin) for chemical production will be summarized according to the reaction type.
Folic acid-modified Prussian blue/polydopamine nanoparticles as an MRI agent for use in targeted chemo/photothermal therapy
Authors: Lin Xiao , Cao Yanbin , Li Jiong , Zheng Dongye , Lan Shanyou , Xue Yanan , Yu Faquan , Wu Ming , Zhu Xunjin
Published: May 2019

A versatile nanotheranostic agent of PB@PDA@PEG-FA-DOX was fabricated for active-targeting and MRI-guided combinatorial chemo/photothermal therapy for cancer.
Reduced fibrous capsule formation at nano-engineered silicone surfaces via tantalum ion implantation
Authors: Park Cheonil , Lee Si-Woo , Kim Jinyoung , Song Eun-Ho , Jung Hyun-Do , Park Ji-Ung , Kim Hyoun-Ee , Kim Sukwha , Jang Tae-Sik
Published: May 2019

Nano-engineered surface of silicone implant improves the biocompatibility and suppresses the fibrous capsule formation which is the most common side effect of polymeric implants.
Gas phase selective propylene epoxidation over La2O3-supported cubic silver nanoparticles
Authors: Yu Bin , Ayvalı Tuğçe , Wang Zhi-Qiang , Gong Xue-Qing , Bagabas Abdulaziz A. , Tsang S. C. Edman
Published: May 2019

It is shown that the Ag nanocube/La2O3 interface catalyses gas phase oxidation of propylene to propylene oxide cooperatively with enhanced selectivity and conversion. Dioxygen is preferentially activated and dissociated by La2O3(001) and the active atomic oxygen over the Ag(100) facet leads to selective propylene epoxidation.
Mono, bis, and tris(phosphoramidate) titanium complexes: synthesis, structure, and reactivity investigations
Authors: Perry Mitchell R. , Gilmour Damon J. , Schafer Laurel L.
Published: May 2019

A series of variously substituted phosphoramidate titanium complexes bearing dimethylamido ligands are reported.
Mangiferin improves hepatic damage-associated molecular patterns, lipid metabolic disorder and mitochondrial dysfunction in alcohol hepatitis rats
Authors: Li Mengran , Wu Chunxiao , Guo Hongbin , Chu Ce , Hu Mingye , Zhou Chengyan
Published: May 2019

Mangiferin ameliorated the progression of AH by regulating the metabolic network associated with damage-associated molecular patterns, lipid metabolic disorder and mitochondrial dysfunction in AH rats.
Anti-obesity effects of instant fermented teas in vitro and in mice with high-fat-diet-induced obesity
Authors: Sun Yue , Wang Yuwan , Song Pengpeng , Wang Haisong , Xu Na , Wang Yijun , Zhang Zhengzhu , Yue Pengxiang , Gao Xueling
Published: May 2019

IDT exerted better anti-obesity effects than PET in HFD-fed mice, as evidenced by reduced BW and regulated obesity-related factors. IDT also showed inhibitory effect on pancreatic lipase in vitro.
Effect of low-ratio n-6/n-3 PUFA on blood glucose: a meta-analysis
Authors: Li Na , Yue Hao , Jia Min , Liu Wei , Qiu Bin , Hou Hanxue , Huang Fenghong , Xu Tongcheng
Published: May 2019

The aim of this meta-analysis was to investigate the effect of increasing dietary low-ratio n-6/n-3 polyunsaturated fatty acid (PUFA) intake on blood glucose and other related indicators.
Two-dimensional graphene paper supported flexible enzymatic fuel cells
Authors: Shen Fei , Pankratov Dmitry , Halder Arnab , Xiao Xinxin , Toscano Miguel D. , Zhang Jingdong , Ulstrup Jens , Gorton Lo , Chi Qijin
Published: May 2019

Application of enzymatic biofuel cells (EBFCs) in wearable or implantable biomedical devices requires flexible and biocompatible electrode materials.
Stochastic modeling of nanoparticle internalization and expulsion through receptor-mediated transcytosis
Authors: Deng Hua , Dutta Prashanta , Liu Jin
Published: May 2019

A stochastic model of clathrin-mediated endocytosis and actin-mediated exocytosis is developed for the study of transcellular nanoparticle transport.
Development of a carbon-11 PET radiotracer for imaging TRPC5 in the brain
Authors: Yu Yanbo , Liang Qianwa , Liu Hui , Luo Zonghua , Hu Hongzheng , Perlmutter Joel S. , Tu Zhude
Published: May 2019

A potent carbon-11 PET tracer targeting TRPC5 was radiosynthesized successfully and the preliminary evaluation in rodents and a nonhuman primate was performed.
Application of surface-enhanced resonance Raman scattering (SERS) to the study of organic functional materials: electronic structure and charge transfer properties of 9,10-bis((E)-2-(pyridin-4-yl)vinyl)anthracene
Authors: Soto Juan , Imbarack Elizabeth , López-Tocón Isabel , Sánchez-Cortés Santiago , Otero Juan C. , Leyton Patricio
Published: May 2019

Surface enhanced Raman spectroscopy in conjunction with quantum chemistry is a valuable tool for characterization of organic functional materials.
Wavelength-dependent photoconductivity of single-walled carbon nanotube layers
Authors: Smirnov Serguei , Anoshkin Ilya V. , Generalov Andrey , Lioubtchenko Dmitri V. , Oberhammer Joachim
Published: May 2019

The optically-tunable dielectric properties of single-walled carbon nanotube layers are wavelength-dependent.
A ruthenium(ii)-catalyzed C–H allenylation-based approach to allenoic acids
Authors: Wu Xiaoyan , Fan Junjie , Fu Chunling , Ma Shengming
Published: May 2019

An efficient Ru-catalyzed approach to tetrasubstituted allenes from benzoic acids and propargylic acetates has been developed.
Diiron oxo reactivity in a weak-field environment
Authors: Johnson Elizabeth J. , Kleinlein Claudia , Musgrave Rebecca A. , Betley Theodore A.
Published: May 2019

A dinucleating cofacial Pacman dipyrrin ligand platform was utilized to isolate diiron bridging oxo complexes in a variety of oxidation states. The interplay between oxidation state and acid/base reactivity in diiron μ-oxo units is explored herein.
Cysteinylprolyl imide (CPI) peptide: a highly reactive and easily accessible crypto-thioester for chemical protein synthesis
Authors: Yanase Masafumi , Nakatsu Koki , Cardos Charlane Joy , Konda Yoshiki , Hayashi Gosuke , Okamoto Akimitsu
Published: May 2019

A new crypto-thioester, cysteinylprolyl imide (CPI) peptide, offers a practical synthetic pathway and reliable reaction rate to be successfully applied to chemical protein synthesis.
Ionization of gold (γ-methoxy)vinyl complexes generates reactive gold vinyl carbene complexes
Authors: Kim Nana , Widenhoefer Ross A.
Published: May 2019

Highly reactive cationic gold vinyl carbene/allylic cation complexes are generated in solution via γ-ionization of gold vinyl complexes.
Structural insights into DNA-stabilized silver clusters
Authors: Schultz Danielle , Brinson Robert G. , Sari Nese , Fagan Jeffrey A. , Bergonzo Christina , Lin Nancy J. , Dunkers Joy P.
Published: May 2019

Sedimentation profiles shows that purified AgDNA nanoclusters exist in both extended (major peak) and compact (minor peak) morphologies.
Tuning of the dynamics of metal ion crosslinked hydrogels by network structures
Authors: Yu Wenting , Sun Wenxu , Fan Qiyang , Xue Bin , Li Yiran , Qin Meng , Li Ying , Chen Bin , Wang Wei , Cao Yi
Published: May 2019

Polymer network structures can affect the crosslinkers through differential swelling forces acting on the crosslinkers, and change the dynamic response of hydrogels.
Host–guest interactions of catechol and 4-ethylcatechol with surface-immobilized blue-box molecules
Authors: Owais Ahmed , Djerdjev Alex M. , Hook James M. , Yuen Alex , Rowlands William , White Nicholas G. , Neto Chiara
Published: May 2019

Surface-immobilized Blue Box molecules remove large amounts of the highly toxic catechol and 4-ethylcatechol from aqueous media, catalyzing the formation of a thin film of poly(catechol).
Dispersive non-noble metal phosphide embedded in alumina arrays derived from layered double hydroxide precursor toward efficient oxygen evolution reaction and biomass upgrading
Authors: Li Mengyuan , Chen Lifang , Ye Shuteng , Fan Guoli , Yang Lan , Zhang Xin , Li Feng
Published: May 2019

3D NiP–Al2O3/NF electrocatalyst was prepared via the reduction of an LDH precursor, which exhibited excellent catalytic performance for OER and biomass upgrading.
Theoretical calculations, molecular dynamics simulations and experimental investigation of the adsorption of cadmium(ii) on amidoxime-chelating cellulose
Authors: Zheng Liuchun , Zhang Shiping , Cheng Wen , Zhang Lijuan , Meng Peipei , Zhang Tao , Yu Huajian , Peng Dan
Published: May 2019

Cd(ii) binds more favorably with C–NH2 in the amidoxime group of ACCS than with CN–OH.
Low-dimensional non-toxic A3Bi2X9 compounds synthesized by a dry mechanochemical route with tunable visible photoluminescence at room temperature
Authors: El Ajjouri Yousra , Chirvony Vladimir S. , Vassilyeva Natalia , Sessolo Michele , Palazon Francisco , Bolink Henk J.
Published: May 2019

We have synthesized fifteen inorganic and hybrid organic–inorganic non-toxic A3Bi2X9 compounds (A = K+, Rb+, Cs+, CH3NH3+ and HC(NH2)2+; X = I−, Br−, Cl−) through dry mechanochemistry.
Modulation of the conductance in platinum(ii) bis(acetylide) molecules through “gating” metal ions
Authors: Duan Ping , Liu Junyang , Wang Jin-Yun , Chen Lichuan , Wang Fei , Zhang Qian-Chong , Hong Wenjing , Chen Zhong-Ning
Published: May 2019

The conductance of molecular wires was precisely regulated by “gating” metals installed on the side of the conductive backbone.
Investigation of blind CFO estimation for GFDM system using universal software radio peripheral: theory, simulations and experiments
Authors: Valluri Siva Prasad , Mani Vakamulla Venkata
Published: May 2019

Generalised frequency division multiplexing (GFDM) utilises a circular pulse shaping mechanism to hinder out‐of‐band emissions and for achieving low latency. However, fallacious synchronisation of this multicarrier technique would lead to severe inter carrier interference and inter symbol interference. Conventional training sequence‐based methods alleviate the effect of time and frequency misalignments by using the concept of data repetition in the pilot preamble, which recedes data efficacy. This study enlightens various aspects in real‐time implementation of blind GFDM signal transceiver using oversampling for carrier frequency offset (CFO) correction in indoor environments. It is observed that the phase shift between neighbouring sample points in an oversampled GFDM symbol is constant throughout the symbol duration. This phase shift is found to be unassociated with either subcarrier or subsymbol indices. Using this property, the maximum likelihood estimate of the CFO is deduced and is analysed in various channel environments. The Cramer–Rao lower bound for the oversampling‐based GFDM signal model is derived and the authors prove through simulation that the proposed algorithm results in a little error floor. The results obtained in simulations have been validated with real‐time test bed built with universal software radio peripheral 2953R as hardware and LabVIEW as software.
Coverage analysis of downlink Poisson networks with double shadowed fading
Authors: Chen Jingrui , Yuan Chaowei
Published: May 2019

In this study, the authors analyse the coverage probability of downlink Poisson networks under a double shadowed (DS) fading channel, where the DS fading composes of lognormal shadowing and – shadowed fading with integer parameters. Firstly, they provide a probability density function of DS fading and approximate it as a weighted sum of – shadowed distributions according to the Gaussian–Hermit quadrature rule. The comprehensive nature and heavy‐tailed feature of the DS fading model are presented. Secondly, under the closest cell‐association rule and the general cell‐association rule, they, respectively, derive closed‐form expressions for the coverage probability of downlink Poisson networks with DS fading. Numerical results show that the DS fading environment with rich clusters and mild fluctuations enlarges the coverage probability of Poisson network under the two types of cell‐association policies. Moreover, the coverage probability decreases as the large‐scale shadowed parameter increases when a severing base station (BS) is selected by the closest cell‐association rule to avoid the ping‐pong effect compared to the general cell‐association rule. The convergence of coverage probability is also validated in the numerical section when the locations of users or BSs are, respectively, modelled by modified Thomas cluster processes.
GNSS multipath estimation and mitigation based on particle filter
Authors: Qin Honglei , Xue Xia , Yang Qian
Published: May 2019

Multipath interference is the main error source for high‐precision positioning applications, and multipath suppression and mitigation is particularly important. Particle filters are widely used to solve non‐linear filtering problems without limitation of Gaussian distribution, and Global navigation satellite system (GNSS) multipath estimation and mitigation based on particle filter are proposed in this study. This approach has four innovations: Firstly, the Kalman‐based multipath signal model is improved to obtain a particle filter multipath signal model, and I and Q two channel signals in the algorithm model solve the coherence correlation phase estimation problem. Secondly, the particle filter algorithm constructs the correlation function using the current particle amplitude and delay. Thirdly, taking full advantage of every particle information, the weighted average is used to calculate state quantity of multipath. Fourthly, three resampling algorithms, including simple random, pseudo‐parallel genetic algorithm and niche genetic algorithm, are taken to resample. Particle filter algorithm for multipath estimation and mitigation based on simulated data and actual navigation satellite signal data is verified. The simulation results show the proposed algorithm has high accuracy in multipath estimation than MEDLL and TK‐MEDLL, especially in multichannel multipath estimation. The actual experimental results show particle filter algorithm is effective for improving the positioning accuracy in complex environments.
Starburst and post-starburst high-redshift protogalaxies
Authors: Owen Ellis R. , Wu Kinwah , Jin Xiangyu , Surajbali Pooja , Kataoka Noriko
Published: May 2019

Quenching of star-formation has been identified in many starburst and post-starburst galaxies, indicating burst-like star-formation histories (SFH) in the primordial Universe. Galaxies undergoing violent episodes of star-formation are expected to be rich in high energy cosmic rays (CRs). We have investigated the role of these CRs in such environments, particularly how they could contribute to this burst-like SFH via quenching and feedback. These high energy particles interact with the baryon and radiation fields of their host via hadronic processes to produce secondary leptons. The secondary particles then also interact with ambient radiation fields to generate X-rays through inverse-Compton scattering. In addition, they can thermalise directly with the semi-ionised medium via Coulomb processes. Heating at a rate of ∼10−25 erg cm−3 s−1can be attained by Coulomb processes in a star-forming galaxy with one core-collapse SN event per decade, and this is sufficient to cause quenching of star-formation. At high-redshift, a substantial amount of CR secondary electron energy can be diverted into inverse-Compton X-ray emission. This yields an X-ray luminosity of above 1041 erg s−1by redshiftz = 7 which drives a further heating effect, operating over larger scales. This would be able to halt inflowing cold gas filaments, strangulating subsequent star-formation. We selected a sample of 16 starburst and post-starburst galaxies at 7 ≲ z ≲ 9 and determine the star-formation rates they could have sustained. We applied a model with CR injection, propagation and heating to calculate energy deposition rates in these 16 sources. Our calculations show that CR feedback cannot be neglected as it has the strength to suppress star-formation in these systems. We also show that their currently observed quiescence is consistent with the suffocation of cold inflows, probably by a combination of X-ray and CR heating.
Formation of interstellar SH+from vibrationally excited H2: Quantum study of S++ H2⇄ SH++ H reaction and inelastic collision
Authors: Zanchet Alexandre , Lique François , Roncero Octavio , Goicoechea Javier R. , Bulut Niyazi
Published: May 2019

The rate constants for the formation, destruction, and collisional excitation of SH+are calculated from quantum mechanical approaches using two new SH+2potential energy surfaces (PESs) of4A″ and2A″ electronic symmetry. The PESs were developed to describe all adiabatic states correlating to the SH+(3Σ−) + H(2S) channel. The formation of SH+through the S++ H2reaction is endothermic by ≈9860 K, and requires at least two vibrational quanta on the H2molecule to yield significant reactivity. Quasi-classical calculations of the total formation rate constant for H2(v = 2) are in very good agreement with the quantum results above 100 K. Further quasi-classical calculations are then performed forv = 3, 4, and 5 to cover all vibrationally excited H2levels significantly populated in dense photodissociation regions (PDR). The new calculated formation and destruction rate constants are two to six times larger than the previous ones and have been introduced in the Meudon PDR code to simulate the physical and illuminating conditions in the Orion bar prototypical PDR. New astrochemical models based on the new molecular data produce four times larger SH+column densities, in agreement with those inferred from recent ALMA observations of the Orion bar.
Dissecting the region around IceCube-170922A: the blazar TXS 0506+056 as the first cosmic neutrino source
Authors: Glauch Theo , Padovani Paolo , Giommi Paolo , Resconi Elisa , Arsioli Bruno , Sahakyan Narek , Huber Matthias
Published: May 2019

On MJD 58018 the IceCube neutrino observatory detected a highlyenergetic, well-reconstructed neutrino, IceCube-170922A, at a distance of 0:1° to a γ-ray flaring blazar, TXS 0506+056. Follow-up searches in archival data additionally revealed a larger flare of neutrinos from the same direction. In order to complete the picture we present here a full multi-wavelength study of the region around IceCube-170922A. While we identify also other non-thermal counterpart candidates, we show that all the evidence points to TXS 0506+056 as the dominant neutrino emitter. Additionally, an analysis of all the available Fermi-LAT data indicates a hard spectrum/low flux of TXS 0506+056 during the neutrino flare in contrast to a soft spectrum/high flux at the arrival time of IceCube-170922A. Putting all the pieces together we conclude that the SED of TXS 0506+056 can be energetically reconnected for both neutrino observations.
The Search for Neutrinos from TXS 0506+056 with the ANTARES Telescope
Authors: Illuminati Giulia
Published: May 2019

A high-energy neutrino, IC170922A, detected by the IceCube experiment was found to be positionally coincident with the direction of a known blazar, TXS 0506+056, observed in γ-rays and at other wavelengths of the electromagnetic spectrum. Here, we present the results of three different searches for neutrino candidates, associated either with the IC170922A event or with the TXS 0506+056 blazar, performed by the ANTARES Collaboration. The three searches, an online follow-up of the IceCube alert, a standard time-integrated point-source analysis and a time-dependent search, yielded no significant observation. Consequently, 90% C.L. upper limits on the one-flavour neutrino flux and fluence have been derived.
Analysis of High Energy Starting Events with the KM3NeT/ARCA detector
Authors: Pikounis Konstantinos , Tzamariudaki Ekaterini , Markou Christos
Published: May 2019

KM3NeT is a research infrastructure housing the next generation neutrino detectors in the depths of the Mediterranean Sea. The ARCA detector, which is currently under construction, is optimized for neutrino searches from astrophysical sources as well as measurements of the diffuse high energy astrophysical flux. The unambiguous detection of neutrinos of extraterrestrial origin by IceCube has led to the first measurement of a high energy astrophysical neutrino flux. The cutting-edge technology used for the design and construction of KM3NeT Digital Optical Modules along with the properties of sea water allow for a measurement of the neutrino direction with an unpresidented resolution for both track and cascade events. Taking advantage of this angular resolution a method to differentiate track and shower events and a method to reject the atmospheric muon background from track-like events were developed and combined to select a sample of high energy starting events. An analysis for the discovery potential of KM3NeT/ARCA for a diffuse astrophysical neutrino flux using these events is presented.
Combined search for dark matter from the Galactic Centre with the ANTARES and IceCube neutrino telescopes
Authors: Gozzini Sara Rebecca , Iovine Nadège , Aguilar Sánchez Juan Antonio , Baur Sebastian , Zornoza Gómez Juan de Dios
Published: May 2019

The ANTARES and IceCube neutrino telescopes have independently searched for neutrinos from dark matter pair-annihilation in the Galactic Centre, and placed limits on the velocity-averaged WIMP annihilation crosssection 〈σν〉. To date, the most stringent limits were obtained by the ANTARES neutrino telescope for WIMP masses > 100 GeV/c2, closely followed by the limits of the IceCube experiment for WIMP masses up to 1 TeV/c2. Here we present the sensitivities of a combined search for dark matter in the Galactic Centre using data from both experiments in a WIMP mass range from 100 GeV/c2 to 1 TeV/c2. This analysis includes IceCube data collected with the complete 86-strings detector from 2012 to 2015 and ANTARES data from 2007 to 2015. The two data sets were combined using a common likelihood framework, and before unblinding the combined sensitivities to 〈σν〉 are shown.
KM3NeT Acquisition Control
Authors: Bozza Cristiano
Published: May 2019

The multi-site nature of the KM3NeT neutrino observatory in the Mediterranean Sea has influenced the development and evolution of its acquisition control software. It is flexible and portable. The same programs are used in data-taking shore stations of neutrino telescopes as well as in testing sites for detector components at different stages of the integration. Flexibility is obtained through high modularity and tight integration with the central database system. The software architecture can be defined as “maximally disconnected” to ensure that no “single point of failure” exists. The most recent development is dynamic resource provisioning and failover, to automatically cope with the possible event of a hardware failure of one or more data taking servers or network elements.
KM3NeT Time Calibration
Authors: Di Palma Irene
Published: May 2019

The KM3NeT detectors are large three-dimensional arrays of several thousands digital optical modules under construction in the Mediterranean Sea. The basic detection element of the neutrino telescope is the digital optical module containing 31 three-inch photomultiplier tubes. Each detection unit, composed of 18 digital optical modules, is a mechanical structure anchored to the sea floor, held vertical by a submerged buoy for the detection of Cherenkov light emitted by charged secondary particles emerging from neutrino interactions. Detector calibration, i.e. timing, positioning and sea-water properties, is overviewed in this talk and discussed in detail in this conference.
A Distributed Storage for Astroparticle Physics
Authors: Kryukov Alexander , Nguyen Minh-Duc
Published: May 2019

In this paper we present the architecture of a distributed data storage for astroparticle physics. The main advantage of the proposed architecture is the possibility to extract data on both file and event level for further processing and analysis. The storage also provides users with a special service allowing to aggregate data from different storages into a single sample. This feature permits to apply multi-messenger methods for more sophisticated investigation of the data. Users can use both Webinterface and Application Programming Interface (API) for accessing the storage.
Opening Remarks ~ Prospects of very high energy cosmic ray interactions for astroparticle physics
Authors: Itow Yoshitaka
Published: May 2019

Hadronic interactions of very high energy cosmic rays have been studied in various aspects of motivation. In recent decades, mainly motivated by air shower experiments, modelling of very high energy cosmic ray interactions have been greatly improved together with new data obtained from high energy colliders such as the LHC. Regarding recent rapid progress of multi-messenger astronomy, a precise knowledge on secondary particle production by cosmic rays at very high energy is largely indispensable. This would give us a new insight and new motivation to study minimum bias hadronic interactions of very high energy cosmic rays.
Muon Measurements with IceTop
Authors: Gonzalez Javier G.
Published: May 2019

We present the measurement of the density of GeV muons in near-vertical air showers by the IceTop array at the South Pole. The muon density is measured at 600 m and 800 m lateral distance from the shower axis in air showers between 1 PeV and 100 PeV. This result can be used to constrain hadronic interaction models by comparing it with the outcome of Monte Carlo simulations. We show that some models do not produce muon densities in agreement with this result unless an unphysical composition of the primary cosmic ray flux is assumed.
Cosmic ray e± at high energy
Authors: Blum Kfir , Reinert Annika
Published: May 2019

There is a commonly expressed opinion in the literature, that cosmic-ray (CR) e+ come from a primary source, which could be dark matter or pulsars. In these proceedings we review some evidence to the contrary: namely, that e+ come from secondary production due to CR nuclei scattering on interstellar matter. We show that recent measurements of the total e± flux at E ≲ 3 TeV are in good agreement with the predicted flux of secondary e±, that would be obtained if radiative energy losses during CR propagation do not play an important role. If the agreement between data and secondary prediction is not accidental, then the requirement of negligible radiative energy losses implies a very short propagation time for high energy CRs: tesc ≲. 105 yr at rigidities R ≳ 3 TV. Such short propagation history may imply that a recent, near-by source dominates the CRs at these energies. We review independent evidence for a transition in CR propagation, based on the spectral hardening of primary and secondary nuclei around R ~ 100 GV. The transition rigidity of the nuclei matches the rigidity at which the e+ flux saturates its secondary upper bound.
Measurements of very-forward energy with the CASTOR calorimeter of CMS
Authors: Baur Sebastian
Published: May 2019

The very-forward energy production in hadron collisions is of paramount importance for the understanding of ultra-high energy cosmic ray air showers. The CASTOR calorimeter of CMS is located at -6:6 < η < -5:2 in the phase-space where the peak of energy is deposited at LHC. The composition and characteristics of the particles in this phase-space have a determining impact on the formation of air shower cascades. An overview of various energy measurements performed with CASTOR is reported and possible implications for cosmic ray physics are outlined.