bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral correlations in a random distributed feedback fibre laser
Authors: Sugavanam Srikanth , Sorokina Mariia , Churkin Dmitry V.
Published: May 2017

Random distributed feedback fibre lasers belong to the class of random lasers, where the feedback is provided by amplified Rayleigh scattering on sub-micron refractive index inhomogenities randomly distributed over the fibre length. Despite the elastic nature of Rayleigh scattering, the feedback mechanism has been insofar deemed incoherent, which corresponds to the commonly observed smooth generation spectra. Here, using a real-time spectral measurement technique based on a scanning Fabry-Pérot interferometer, we observe long-living narrowband components in the random fibre laser’s spectrum. Statistical analysis of the ∼104 single-scan spectra reveals a preferential interspacing for the components and their anticorrelation in intensities. Furthermore, using mutual information analysis, we confirm the existence of nonlinear correlations between different parts of the random fibre laser spectra. The existence of such narrowband spectral components, together with their observed correlations, establishes a long-missing parallel between the fields of random fibre lasers and conventional random lasers.
Signal recognition particle prevents N-terminal processing of bacterial membrane proteins
Authors: Ranjan Amitabh , Mercier Evan , Bhatt Arshiya , Wintermeyer Wolfgang
Published: May 2017

Bacterial proteins are synthesized with an N-formylated amino-terminal methionine, and N-formylated peptides elicit innate-immunity responses against bacterial infections. However, the source of these formylated peptides is not clear, as most bacterial proteins are co-translationally deformylated by peptide deformylase. Here we develop a deformylation assay with translating ribosomes as substrates, to show that the binding of the signal recognition particle (SRP) to signal sequences in nascent proteins on the ribosome prevents deformylation, whereas deformylation of nascent proteins without signal sequence is not affected. Deformylation and its inhibition by SRP are not influenced by trigger factor, a chaperone that interacts with nascent chains on the ribosome. We propose that bacterial inner-membrane proteins, in particular those with N-out topology, can retain their N-terminal formyl group during cotranslational membrane insertion and supply formylated peptides during bacterial infections.
Natural Convection Flow of a Nanofluid in an Inclined Square Enclosure Partially Filled with a Porous Medium
Authors: Alsabery A. I. , Chamkha A. J. , Saleh H. , Hashim I.
Published: May 2017

This work analyses free convection flow of a nanofluid in an inclined square enclosure consisting of a porous layer and a nanofluid layer using the finite difference methodology. Sinusoidal temperature boundary conditions are imposed on the two opposing vertical walls. Nanofluids with water as base and Ag or Cu or Al2O3 or TiO2 nanoparticles are considered for the problem. The related parameters of this study are the Darcy number, nanoparticle volume fraction, phase deviation, amplitude ratio, porous layer thickness and the inclination angle of the cavity. A comparison with previously published work is performed and the results are in good agreement. Detailed numerical data for the fluid flow and thermal distributions inside the square enclosure, and the Nusselt numbers are presented. The obtained results show that the heat transfer is considerably affected by the porous layer increment. Several nanoparticles depicted a diversity improvement on the convection heat transfer.
A seven-million-year hornblende mineral record from the central Chinese Loess Plateau
Authors: He Tong , Liu Lianwen , Chen Yang , Sheng Xuefen , Ji Junfeng
Published: May 2017

Previous studies of the late Cenozoic erosion rate have yielded different views—long-term stable rates or a significant increase at climate transitions—leading to uncertainty concerning the hypothesized global erosion rate controlled by either tectonic uplift or climatic changes. Here, we present a seven-million-year hornblende mineral record along the Lingtai section of the Chinese Loess Plateau. By examining the spatial distribution of hornblende minerals in seven desert basins, which are potential loess source areas, we constructed a ratio of hornblende versus total heavy minerals to reflect past changes in physical/chemical weathering strength. Our results demonstrate that the ratio has generally increased since 7 Ma, with three significant shifts recorded at 2.6 Ma, 1.4 Ma and 0.5 Ma linked to the onset, continuation and expansion of the Northern Hemisphere glaciation, respectively. Given that chemical weathering during the diagenetic history produces a trend of smoothly increasing hornblende migrating upwards, the three shifts at these boundaries can be interpreted as changes in the bedrock erosion rate on the northern Tibetan Plateau, which may be related to tectonic uplift events and incision of the Yellow River. Evidence presented here supports the idea of coupling between climate change, tectonic uplift and regional erosion.
Ribosomal protein L23 negatively regulates cellular apoptosis via the RPL23/Miz-1/c-Myc circuit in higher-risk myelodysplastic syndrome
Authors: Qi Yuekun , Li Xiao , Chang Chunkang , Xu Feng , He Qi , Zhao Youshan , Wu Lingyun
Published: May 2017

Ribosomal protein (RP) L23 is a negative regulator of cellular apoptosis, and RPL23 overexpression is associated with abnormal apoptotic resistance in CD34+ cells derived from patients with higher-risk myelodysplastic syndrome (MDS). However, the mechanism underlying RPL23-induced apoptotic resistance in higher-risk MDS patients is poorly understood. In this study, we showed that reduced RPL23 expression led to suppressed cellular viability, increased apoptosis and G1-S cell cycle arrest. Gene microarray analysis comparing RPL23-knockdown and control cells identified an array of differentially expressed genes, of which, Miz-1, was upregulated with transactivation of the cell cycle inhibitors p15Ink4band p21Cip1, and Miz-1’s functional repressor, c-Myc, was downregulated. Cells derived from higher-risk MDS patients demonstrated consistently increased expression of RPL23 and c-Myc and decreased Miz-1 expression compared with cells from lower-risk patients. In conclusion, Miz-1-dependent induction of p15Ink4band p21Cip1was depressed with decreased Miz-1 and increased c-Myc expression under conditions of elevated RPL23 expression, leading to apoptotic resistance in higher-risk MDS patients. Because RPL23 is encoded by a target gene of c-Myc, the RPL23/Miz-1/c-Myc regulatory circuit provides a feedback loop that links efficient RPL23 expression with c-Myc’s function to suppress Miz-1-induced Cdk inhibitors and thereby leads to apoptotic resistance in higher-risk MDS patients.
Hunger enhances consistent economic choices in non-human primates
Authors: Yamada Hiroshi
Published: May 2017

Hunger and thirst are fundamental biological processes that drive consumption behavior in humans and non-human animals. While the existing literature in neuroscience suggests that these satiety states change how consumable rewards are represented in the brain, it remains unclear as to how they change animal choice behavior and the underlying economic preferences. Here, I used combined techniques from experimental economics, psychology, and neuroscience to measure food preferences of marmoset monkeys (Callithrix jacchus), a recently developed primate model for neuroscience. Hunger states of animals were manipulated by scheduling feeding intervals, resulting in three different conditions: sated, non-sated, and hungry. During these hunger states, animals performed pairwise choices of food items, which included all possible pairwise combinations of five different food items except for same-food pairs. Results showed that hunger enhanced economic rationality, evident as a decrease of transitivity violations (item A was preferred to item B, and B to C, but C was preferred to A). Further analysis demonstrated that hungry monkeys chose more-preferred items over less-preferred items in a more deterministic manner, while the individual food preferences appeared to remain stable across hunger states. These results suggest that hunger enhances consistent choice behavior and shifts animals towards efficient outcome maximization.
Combinatory Evaluation of Transcriptome and Metabolome Profiles of Low Temperature-induced Resistant Ascites Syndrome in Broiler Chickens
Authors: Shi Shourong , Shen Yiru , Zhang Shan , Zhao Zhenhua , Hou Zhuocheng , Zhou Huaijun , Zou Jianmin , Guo Yuming
Published: May 2017

To select metabolic biomarkers and differentially expressed genes (DEGs) associated with resistant-ascites syndrome (resistant-AS), we used innovative techniques such as metabolomics and transcriptomics to comparatively examine resistant-AS chickens and AS controls. Metabolomic evaluation of chicken serum using ultra-performance liquid chromatography-quadruple time-of-flight high-sensitivity mass spectrometry (UPLC-QTOF/HSMS) showed significantly altered lysoPC(18:1), PE(18:3/16:0), PC(20:1/18:3), DG(24:1/22:6/0:0), PS(18:2/18:0), PI(16:0/16:0), PS(18:0/18:1), PS(14:1/14:0), dihydroxyacetone, ursodeoxycholic acid, tryptophan, L-valine, cycloserine, hypoxanthine, and 4-O-Methylmelleolide concentrations on day 21 and LysoPC(18:0), LysoPE(20:1/0:0), LysoPC(16:0), LysoPE(16:0/0:0), hypoxanthine, dihydroxyacetone, 4-O-Methylmelleolide, LysoPC(18:2), and PC(14:1/22:1) concentrations on day 35, between the susceptible and resistant groups. Compared to the susceptible group, transcriptomic analysis of liver samples using RNA-seq revealed 413 DEGs on day 21 and 214 DEGs on day 35 in the resistant group. Additional evaluations using gene ontology (GO) indicate that significant enrichment occurred in the oxygen transportation, defensive reactions, and protein modifications of the decreased DEGs as well as in the cell morphological formation, neural development, and transforming growth factor (TGF)-beta signalling of the increased DEGs on day 21. Oxygen transportation was also significantly enriched for downregulated DEGs on day 35. The combinatory evaluation of the metabolome and the transcriptome suggests the possible involvement of glycerophospholipid metabolism in the development of resistant-AS in broilers.
Functional compressive mechanics and tissue biocompatibility of an injectable SF/PU hydrogel for nucleus pulposus replacement
Authors: Hu Jingen , Lu Yang , Cai Ling , Owusu-Ansah Kwabena Gyabaah , Xu Gewen , Han Feilong , Bao Junjie , Lin Xiangjin , Huang Yiping
Published: May 2017

In spinal degenerative disease, an injectable liquid hydrogel can fill in defect entirely, lessen the danger of implant relocation and following loss of disc height, minimizing the operative trauma. Here, we propose an injectable in-situ chemically cross-linked hydrogel by a two-component reaction of liquid silk fibroin with liquid polyurethane at physiological temperature conditions. Confined compression tests and fatigue tests were reported to assess physical properties of the hydrogel. Impact of different diameter on the biomechanical behaviours was tested to evaluate the clinical potentiality of the hydrogel for replacing nucleus pulposus. Degradation behaviours in different solutions and animal experiments were also investigated to examine the tissue biocompatibility of the hydrogel. The hydrogel modulus was affected by the hydrogel geometrical (diameter) parameters. SF/PU composite hydrogel can survive a million cycles, unconstrained fatigue resistance. More importantly, in vivo biocompatibility using New Zealand white rabbits, showed good biocompatibility over a three-month period in culture. Particularly, they showed the significant clinical merit of providing stronger axial compressive stiffness on confined compression test. Based on the outcomes of the present research, the SF/PU composite hydrogel may provide significant advantages for use in future clinical application in replacing nucleus pulposus field.
Manipulation of Rat Movement via Nigrostriatal Stimulation Controlled by Human Visually Evoked Potentials
Authors: Koo Bonkon , Koh Chin Su , Park Hae-Yong , Lee Hwan-Gon , Chang Jin Woo , Choi Seungjin , Shin Hyung-Cheul
Published: May 2017

Here, we report that the development of a brain-to-brain interface (BBI) system that enables a human user to manipulate rat movement without any previous training. In our model, the remotely-guided rats (known as ratbots) successfully navigated a T-maze via contralateral turning behaviour induced by electrical stimulation of the nigrostriatal (NS) pathway by a brain- computer interface (BCI) based on the human controller’s steady-state visually evoked potentials (SSVEPs). The system allowed human participants to manipulate rat movement with an average success rate of 82.2% and at an average rat speed of approximately 1.9 m/min. The ratbots had no directional preference, showing average success rates of 81.1% and 83.3% for the left- and right-turning task, respectively. This is the first study to demonstrate the use of NS stimulation for developing a highly stable ratbot that does not require previous training, and is the first instance of a training-free BBI for rat navigation. The results of this study will facilitate the development of borderless communication between human and untrained animals, which could not only improve the understanding of animals in humans, but also allow untrained animals to more effectively provide humans with information obtained with their superior perception.
Identification of the matricellular protein Fibulin-5 as a target molecule of glucokinase-mediated calcineurin/NFAT signaling in pancreatic islets
Authors: Okuyama Tomoko , Shirakawa Jun , Yanagisawa Hiromi , Kyohara Mayu , Yamazaki Shunsuke , Tajima Kazuki , Togashi Yu , Terauchi Yasuo
Published: May 2017

Glucokinase-mediated glucose signaling induces insulin secretion, proliferation, and apoptosis in pancreatic β-cells. However, the precise molecular mechanisms underlying these processes are not clearly understood. Here, we demonstrated that glucokinase activation using a glucokinase activator (GKA) significantly upregulated the expression of Fibulin-5 (Fbln5), a matricellular protein involved in matrix-cell signaling, in isolated mouse islets. The isletFbln5expression was induced by ambient glucose in a time- and dose-dependent manner and further enhanced by high-fat diet or the deletion of insulin receptor substrate 2 (IRS-2), whereas the GKA-induced increase inFbln5expression was diminished inIrs-2-deficient islets. GKA-inducedFbln5upregulation in the islets was blunted by a glucokinase inhibitor, KATPchannel opener, Ca2+channel blocker and calcineurin inhibitor, while it was augmented by harmine, a dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) 1 A inhibitor. Although deletion ofFbln5in mice had no significant effects on the glucose tolerance or β-cell functions, adenovirus-mediatedFbln5overexpression increased glucose-stimulated insulin secretion in INS-1 rat insulinoma cells. Since the islet Fbln5 expression is regulated through a glucokinase/KATPchannel/calcineurin/nuclear factor of activated T cells (NFAT) pathway crucial for the maintenance of β-cell functions, further investigation of Fbln5 functions in the islets is warranted.
Low level of Lck kinase in Th2 cells limits expression of CD4 co-receptor and S73 phosphorylation of transcription factor c-Jun
Authors: Shebzukhov Yury V. , Stanislawiak Silke , Bezhaeva Taisiya R. , Nedospasov Sergei A. , Kuprash Dmitry V.
Published: May 2017

The Src-family tyrosine kinase Lck is an enzyme associated with the CD4 and CD8 co-receptors and promoting signaling through the T cell receptor (TCR) complex. The levels of Lck expression and activity change during the development and differentiation of T cells. Here we show that Lck expression is higher in Th1 cells as compared to Th2 cells. Ectopic overexpression of Lck in Th2 cells results in increased expression of CD4 co-receptor and enhanced S73 phosphorylation of transcription factor c-Jun. Our findings indicate that TCR-mediated signaling in Th2 cells may be directly attenuated by Lck protein expression level.
The Absence of Interferon-β Promotor Stimulator-1 (IPS-1) Predisposes to Bronchiolitis and Asthma-like Pathology in Response to Pneumoviral Infection in Mice
Authors: Simpson Jennifer , Lynch Jason P. , Loh Zhixuan , Zhang Vivian , Werder Rhiannon B. , Spann Kirsten , Phipps Simon
Published: May 2017

Respiratory syncytial virus (RSV)-bronchiolitis is a major cause of infant morbidity and mortality and a risk factor for subsequent asthma. We showed previously that toll-like receptor (TLR)7 in plasmacytoid dendritic cells (pDCs) is critical for protection against bronchiolitis and asthma in mice infected with pneumonia virus of mice (PVM), the mouse homolog of RSV. This lack of redundancy was unexpected as interferon-β promotor stimulator-1 (IPS-1) signalling, downstream of RIG-I-like receptor (RLR) and not TLR7 activation, contributes to host defence in hRSV-inoculated adult mice. To further clarify the role of IPS-1 signalling, we inoculated IPS-1−/−and WT mice with PVM in early-life, and again in later-life, to model the association between bronchiolitis and asthma. IPS-1 deficiency predisposed to severe PVM bronchiolitis, characterised by neutrophilic inflammation and necroptotic airway epithelial cell death, high mobility group box 1 (HMGB1) and IL-33 release, and downstream type-2 inflammation. Secondary infection induced an eosinophilic asthma-like pathophysiology in IPS-1−/−but not WT mice. Mechanistically, we identified that IPS-1 is necessary for pDC recruitment, IFN-α production and viral control. Our findings suggest that TLR7 and RLR signalling work collaboratively to optimally control the host response to pneumovirus infection thereby protecting against viral bronchiolitis and subsequent asthma.
Sediment transport capacity of concentrated flows on steep loessial slope with erodible beds
Authors: Xiao Hai , Liu Gang , Liu Puling , Zheng Fenli , Zhang Jiaqiong , Hu Feinan
Published: May 2017

Previous research on sediment transport capacity has been inadequate and incomplete in describing the detachment and transport process of concentrated flows on slope farmlands during rill development. An indoor concentrated flow scouring experiment was carried out on steep loessial soil slope with erodible bed to investigate the sediment transport capacity under different flow rates and slope gradients. The results indicated that the sediment transport capacity increases with increasing flow rate and slope gradient, and these relationships can be described by power functions and exponential functions, respectively. Multivariate, nonlinear regression analysis showed that sediment transport capacity was more sensitive to slope gradient than to flow rate, and it was more sensitive to unit discharge per unit width than to slope gradient for sediment transport capacity in this study. When similar soil was used, the results were similar to those of previous research conducted under both erodible and non-erodible bed conditions. However, the equation derived from previous research under non-erodible bed conditions with for river bed sand tends to overestimate sediment transport capacity in our experiment.
Modelling farm-to-farm disease transmission through personnel movements: from visits to contacts, and back
Authors: Rossi Gianluigi , Smith Rebecca L. , Pongolini Stefano , Bolzoni Luca
Published: May 2017

Infectious diseases in livestock can be transmitted through fomites: objects able to convey infectious agents. Between-farm spread of infections through fomites is mostly due to indirect contacts generated by on-farm visits of personnel that can carry pathogens on their clothes, equipment, or vehicles. However, data on farm visitors are often difficult to obtain because of the heterogeneity of their nature and privacy issues. Thus, models simulating disease spread between farms usually rely on strong assumptions about the contribution of indirect contacts on infection spread. By using data on veterinarian on-farm visits in a dairy farm system, we built a simple simulation model to assess the role of indirect contacts on epidemic dynamics compared to cattle movements (i.e. direct contacts). We showed that including in the simulation model only specific subsets of the information available on indirect contacts could lead to outputs widely different from those obtained with the full-information model. Then, we provided a simple preferential attachment algorithm based on the probability to observe consecutive on-farm visits from the same operator that allows overcoming the information gaps. Our results suggest the importance of detailed data and a deeper understanding of visit dynamics for the prevention and control of livestock diseases.
Amygdalar Endothelin-1 Regulates Pyramidal Neuron Excitability and Affects Anxiety
Authors: Chen Ming , Yan Huan-huan , Shu Shu , Pei Lei , Zang Long-kai , Fu Yu , Wang Ze-fen , Wan Qi , Bi Lin-lin
Published: May 2017

An abnormal neuronal activity in the amygdala is involved in the pathogenesis of anxiety disorders. However, little is known about the mechanisms. High-anxiety mice and low-anxiety mice, representing the innate extremes of anxiety-related behaviors, were first grouped according to their anxiety levels in the elevated plus maze test. We found that the mRNA for endothelin-1 (ET1) and ET1 B-type receptors (ETBRs) in the amygdala was down-regulated in high-anxiety mice compared with low-anxiety mice. Knocking down basolateral amygdala (BLA) ET1 expression enhanced anxiety-like behaviors, whereas over-expressing ETBRs, but not A-type receptors (ETARs), had an anxiolytic effect. The combined down-regulation of ETBR and ET1 had no additional anxiogenic effect compared to knocking down the ETBR gene alone, suggesting that BLA ET1 acts through ETBRs to regulate anxiety-like behaviors. To explore the mechanism underlying this phenomenon further, we verified that most of the ET1 and the ET1 receptors in the BLA were expressed in pyramidal neurons. The ET1–ETBR signaling pathway decreased the firing frequencies and threshold currents for the action potentials of BLA pyramidal neurons but did not alter BLA synaptic neurotransmission. Together, these results indicate that amygdalar ET1-ETBR signaling could attenuate anxiety-like behaviors by directly decreasing the excitability of glutamatergic neurons.
Three-Dimensionally Conformal Porous Microstructured Fabrics via Breath Figures: A Nature-Inspired Approach for Novel Surface Modification of Textiles
Authors: Gong Jianliang , Xu Bingang , Tao Xiaoming
Published: May 2017

Breath figures (BFs) are a kind of water droplet arrays that can be formed by condensing aqueous vapor onto a cold surface, such as dewy phenomenon on a spider web. This study developed a BF-inspired approach for direct introduction of desired materials onto the textile surfaces with three-dimensionally conformal porous microstructures by the evaporation of solution-coated fabric under high humidity environment, which brings a brand-new kind of modified textiles, three-dimensionally conformal porous microstructured fabrics (CPMFs). Such kind of CPMFs can possess customized multifunctional properties of introduced materials, and meanwhile maintain the inherent properties and unique texture features of fabrics. This nature-inspired BF approach is robust and versatile for customized preparation of CPMFs based on different fabrics with different common polymers. Moreover, it is also feasible for one-step functionalization of CPMFs by the incorporation of nanoparticles (such as titanium dioxide nanoparticles, TiO2 NPs) into the porous microstructures during the BF process. Comparing to the sample modified without porous microstructures, the resultant TiO2 NPs-incorporated CPMFs show an obviously enhanced performance on photocatalytic degradation of pollutants under the same ultraviolet irradiation conditions.
A core extended naphtalene diimide G-quadruplex ligand potently inhibits herpes simplex virus 1 replication
Authors: Callegaro Sara , Perrone Rosalba , Scalabrin Matteo , Doria Filippo , Palù Giorgio , Richter Sara N.
Published: May 2017

G-quadruplexes (G4s) are nucleic acids secondary structures, epigenetic regulators in cells and viruses. In herpes simplex virus 1 (HSV-1)-infected cells, G4s are massively present during viral replication. We here aimed at investigating the possibility to target the HSV-1 G4s by a core extended naphtalene diimide (c-exNDI) G4 ligand. Biophysical and biomolecular analysis proved that c-exNDI stabilized the HSV-1 G4s in a concentration dependent manner. In MS competition assays, c-exNDI preferentially recognized HSV-1 G4s over cellular telomeric G4s, the most represented G4s within cells; other less abundant cellular G4s were also recognized. Treatment of HSV-1 infected cells with c-exNDI at low nanomolar concentrations induced significant virus inhibition with no cytotoxicity. The mechanism of action was ascribed to G4-mediated inhibition of viral DNA replication, with consequent impairment of viral genes transcription. Our data suggest that the observed potent antiviral activity and low cytotoxicity mainly depend on a combination of c-exNDI affinity for HSV-1 G4s and their massive presence during infection. HSV-1 G4s may thus represent new effective antiviral targets: the fact that no current antiherpetic drug exploits them and their presence at the viral genome, responsible for both active and latent HSV infections, makes them particularly attracting.
Regulation of chloroplast and nucleomorph replication by the cell cycle in the cryptophyte Guillardia theta
Authors: Onuma Ryo , Mishra Neha , Miyagishima Shin-ya
Published: May 2017

The chloroplasts of cryptophytes arose through a secondary endosymbiotic event in which a red algal endosymbiont was integrated into a previously nonphotosynthetic eukaryote. The cryptophytes retain a remnant of the endosymbiont nucleus (nucleomorph) that is replicated once in the cell cycle along with the chloroplast. To understand how the chloroplast, nucleomorph and host cell divide in a coordinated manner, we examined the expression of genes/proteins that are related to nucleomorph replication and chloroplast division as well as the timing of nuclear and nucleomorph DNA synthesis in the cryptophyte Guillardia theta. Nucleus-encoded nucleomorph HISTONE H2A mRNA specifically accumulated during the nuclear S phase. In contrast, nucleomorph-encoded genes/proteins that are related to nucleomorph replication and chloroplast division (FtsZ) are constantly expressed throughout the cell cycle. The results of this study and previous studies on chlorarachniophytes suggest that there was a common evolutionary pattern in which an endosymbiont lost its replication cycle-dependent transcription while cell-cycle-dependent transcriptional regulation of host nuclear genes came to restrict the timing of nucleomorph replication and chloroplast division.
Copper(i)-mediated carboamination of vinyl azides by aryldiazonium salts: synthesis of N2-substituted 1,2,3-triazoles
Authors: Liu Zhenhua , Ji Huimin , Gao Wen , Zhu Guangyu , Tong Lili , Lei Fengcai , Tang Bo
Published: May 2017

Copper(i)-mediated carboamination reaction of vinyl azides with sole aryldiazonium salt for N2-substituted 1,2,3-triazoles.
Photodynamics of Zr-based MOFs: effect of explosive nitroaromatics
Authors: Gutiérrez M. , Navarro R. , Sánchez F. , Douhal A.
Published: May 2017

The present work describes the fluorescence spectroscopy and photodynamics of two different Zr mixed-linkers MOFs (Zr-NDC/Tz and Zr-NDC/CN) and their interactions with nitroaromatics.
Dewetting acrylic polymer films with water/propylene carbonate/surfactant mixtures – implications for cultural heritage conservation
Authors: Baglioni M. , Montis C. , Brandi F. , Guaragnone T. , Meazzini I. , Baglioni P. , Berti D.
Published: May 2017

The surfactant lowers the interfacial energy between the phases, favoring polymer dewetting.
3D measurement and simulation of surface acoustic wave driven fluid motion: a comparison
Authors: Kiebert Florian , Wege Stefan , Massing Julian , König Jörg , Cierpka Christian , Weser Robert , Schmidt Hagen
Published: May 2017

We present a quantitative 3D comparison between experimental measurements and numerical simulations of the acoustic streaming induced velocity field.
Immortal ring-opening polymerization of lactides with super high monomer to catalyst ratios initiated by zirconium and titanium complexes containing multidentate amino-bis(phenolate) ligands
Authors: Wang Baolong , Zhao Huanqin , Wang Liying , Sun Junmin , Zhang Yongfeng , Cao Zhenzhu
Published: May 2017

Zirconium and titanium complexes containing amino-bis(phenolate) ligands were prepared. These complexes are highly active initiators for the ring-opening polymerization of lactide. And two zirconium complexes are highly active and excellent catalysts for immortal ring-opening polymerization of lactide.
Indocyanine green-loaded gold nanostars for sensitive SERS imaging and subcellular monitoring of photothermal therapy
Authors: Chen Jing , Sheng Zonghai , Li Penghui , Wu Manxiang , Zhang Nisi , Yu Xue-Feng , Wang Yuanwen , Hu Dehong , Zheng Hairong , Wang Guo Ping
Published: May 2017

A nanothermometer was incorporated in GNS-ICG-BSA nanoprobes to realize SERS imaging-based real-time sensitive monitoring of intracellular temperature in PTT.
Endomorphin-1 analogs containing α-methyl-β-amino acids exhibit potent analgesic activity after peripheral administration
Authors: Wang Yuan , Yang Junxian , Liu Xin , Zhao Long , Yang Dongxu , Zhou Jingjing , Wang Dan , Mou Lingyun , Wang Rui
Published: May 2017

C-Terminal substitution with aromatic β2,3-amino acids can improve the bioactivity and bioavailability of endomorphin-1.
Self-sacrificed two-dimensional REO(CH3COO) template-assisted synthesis of ultrathin rare earth oxide nanoplates
Authors: Liu Rui , Wu Ke , Li Lin-Dong , Sun Ling-Dong , Yan Chun-Hua
Published: May 2017

Ultrathin RE2O3nanoplates are synthesized by a hot-injection methodviathein situformed REO(CH3COO) template.
Synthesis, characterization and application of TiO2/Ag recyclable SERS substrates
Authors: Huang Qingli , Li Jing , Wei Wenxian , Wu Yongping , Li Ting
Published: May 2017

In this paper, rutile and anatase TiO2/Ag nanocomposites were prepared by a facile and green photochemical method.
Synthesis of polymeric nano-objects of various morphologies based on block copolymer self-assembly using microporous membranes
Authors: Agustina Sri , Tokuda Masayoshi , Minami Hideto , Boyer Cyrille , Zetterlund Per B.
Published: May 2017

Polymeric nano-objects of a range of morphologies have been prepared using a novel approach based on the use of microporous membranes for mixing of a solvent (containing a diblock copolymer) and a non-solvent.
Visualizing the bidirectional electron transfer in a Schottky junction consisting of single CdS nanoparticles and a planar gold film
Authors: Li Zhimin , Fang Yimin , Wang Yongjie , Jiang Yingyan , Liu Tao , Wang Wei
Published: May 2017

The surface plasmon polaritons induced the injection of a hot electron into the CdS nanoparticles at a Schottky junction.
Single copy-sensitive electrochemical assay for circulating methylated DNA in clinical samples with ultrahigh specificity based on a sequential discrimination–amplification strategy
Authors: Wang Xuyao , Chen Feng , Zhang Dexin , Zhao Yue , Wei Jing , Wang Lihua , Song Shiping , Fan Chunhai , Zhao Yongxi
Published: May 2017

A sequential discrimination–amplification (SEDA) electrochemical strategy was constructed for the identification of single-copy circulating methylated DNA.
Nanoscale metal–organic frameworks coated with poly(vinyl alcohol) for ratiometric peroxynitrite sensing through FRET
Authors: Ding Zhaoyang , Tan Jinyun , Feng Gang , Yuan Zhen , Wu Changfeng , Zhang Xuanjun
Published: May 2017

This work describes a facile yet powerful approach to energy-transfer NMOF (nanoscale metal–organic framework) fabrication for ratiometric peroxynitrite (ONOO−) sensing.
Two-photon AIE bio-probe with large Stokes shift for specific imaging of lipid droplets
Authors: Jiang Meijuan , Gu Xinggui , Lam Jacky W. Y. , Zhang Yilin , Kwok Ryan T. K. , Wong Kam Sing , Tang Ben Zhong
Published: May 2017

A novel AIEgen with prominent two-photon excitation was rationally developed for specific lipid-droplet imaging in cells and tissues.
ZnO nanoparticles as an antimicrobial tissue adhesive for skin wound closure
Authors: Gao Yu , Han Yiyuan , Cui Mingyue , Tey Hong Liang , Wang Lianhui , Xu Chenjie
Published: May 2017

A solution of zinc oxide nanoparticles was explored as an antimicrobial tissue adhesive for skin wound closure.
Kidney–brain axis inflammatory cross-talk: from bench to bedside
Authors: Miranda Aline Silva , Cordeiro Thiago Macedo , dos Santos Lacerda Soares Thomas Mucida , Ferreira Rodrigo Novaes , Simões e Silva Ana Cristina
Published: May 2017

Epidemiologic data suggest that individuals at all stages of chronic kidney disease (CKD) have a higher risk of developing neuropsychiatric disorders, cognitive impairment, and dementia. This risk is generally explained by the high prevalence of both symptomatic and subclinical ischemic cerebrovascular lesions. However, other potential mechanisms, including cytokine/chemokine release, production of reactive oxygen species (ROS), circulating and local formation of trophic factors and of renin–angiotensin system (RAS) molecules, could also be involved, especially in the absence of obvious cerebrovascular disease. In this review, we discuss experimental and clinical evidence for the role of these mechanisms in kidney–brain cross-talk. In addition, we hypothesize potential pathways for the interactions between kidney and brain and their pathophysiological role in neuropsychiatric and cognitive changes found in patients with CKD. Understanding the pathophysiologic interactions between renal impairment and brain function is important in order to minimize the risk for future cognitive impairment and to develop new strategies for innovative pharmacological treatment.
Low‐power TDC scheme using DLL‐based gray counter for infrared imagers
Authors: Liu Dahe , Lu Wengao , Yu Shanzhe , Chen Zhongjian
Published: May 2017

A low‐power time‐to‐digital converter (TDC) scheme for column‐level single‐slope analogue‐to‐digital converters for infrared imager is presented. This scheme greatly improves the TDC's timing precision with a novel 3‐bit fine gray counter, which makes use of multi‐phase clocks from a delay‐lock‐loop. Aimed for 384 × 288 array size uncooled infrared imager with 17 μm pixel pitch, the TDC circuits have been developed and simulated employing 0.18 μm CMOS technology. Compared with conventional two‐step TDC methods, this method saves more chip area and reduces the sampling power consumption by >50%, and also eliminates the coarse‐fine inconsistency problem with a simulated ±0.1 least‐significant‐bit differential non‐linearity performance.
Analysis of synchronous parasitic torque in dual skew cage rotor induction motors with equivalent slot number
Authors: Wang Lang , Bao Xiaohua , Di Chong , Zhou Yang , Lu Qinfen
Published: May 2017

The squirrel‐cage induction motor with equivalent slot number may have starting problem due to synchronous locking torque. This study adopts dual skew rotor structure to solve that problem. First, the distribution of rotor slot harmonics is described. Second, the synchronous parasitic torque acting on the rotor is calculated. Eddy‐current field simulation is implemented to calculate locking torque in three kinds of structure rotors squirrel‐cage induction motor with equivalent slot. The induction motor with straight rotor hardly line starts in some rotor position, which illustrates that skew rotor can attenuate the synchronous parasitic torque, but cannot remove it. The dual skew rotor can remove the synchronous parasitic torque in which odd rotor slot harmonics interact with the unassociated stator harmonics, and also attenuate others. The validity of this rotor structure is verified by simulation study and also experiment.
Design considerations for high‐power converters interfacing 10 MW superconducting wind power generators
Authors: Vedreño‐Santos Francisco , Odavic Milijana , Guan Yang , Azar Ziad , Thomas Arwyn Sean , Li Guang‐Jin , Zhu Zi‐Qiang
Published: May 2017

The design of power electronic converters for the integration of wind generated power into the grid is more and more important due to a new class of superconducting generators (SG) with power ratings of up to 20 MW. High efficiency of power converters for high‐power applications is mandatory in order to reduce the overall cost of the system. This study proposes a design method to minimise the cost of the system by finding the optimal number of power devices and capacitors for different high‐power converter topologies. The investigation focuses on determining the optimal number of voltage levels for a back‐to‐back (BTB) neutral point clamped (NPC) converter. The design method is demonstrated by estimating the cost of different BTB NPC power converter topologies for the integration of a 10 MW SG to the grid.
Calibration model for detection of potential demodulating behaviour in biological media exposed to RF energy
Authors: See Chan H. , Abd‐Alhameed Raed A. , Ghani Arfan , Ali Nazar T. , Excell Peter S. , McEwan Neil J. , Balzano Quirino
Published: May 2017

Potential demodulating ability in biological tissue exposed to radio‐frequency (RF) signals intrinsically requires an unsymmetrical diode‐like non‐linear response in tissue samples. This may be investigated by observing possible generation of the second harmonic in a cavity resonator designed to have fundamental and second harmonic resonant frequencies with collocated antinodes. Such a response would be of interest as being a mechanism that could enable demodulation of information‐carrying waveforms having modulating frequencies in ranges that could interfere with cellular processes. Previous studies have developed an experimental system to test for such responses: the present study reports a circuit model to facilitate calibration of any non‐linear RF energy conversion occurring within a test‐piece inside the cavity. The method is validated computationally and experimentally using a well‐characterised non‐linear device. The proposed model demonstrates that the sensitivity of the measurement equipment plays a vital role in deciding the required input power to detect any second harmonic signal, which is expected to be very weak. The model developed here provides a lookup table giving the level of the second harmonic signal in the detector as a function of the input power applied in a measurement. Experimental results are in good agreement with the simulated results.
Three‐axis capacitive force sensor with liquid metal electrodes for endoscopic palpation
Authors: Nagatomo Tatsuho , Miki Norihisa
Published: May 2017

Endoscopic palpation is a promising technology for detecting tumours that are too small to be detected by CT and magnetic resonance imaging, are not located on tissue surfaces, and cannot be observed using endoscopes. This method uses a small force sensor mounted on the tip of an endoscope. It is desirable that the sensor can scan tissue surfaces and continuously measure the stiffness of organs. Prior work developed a ballpoint‐pen‐like capacitive force sensor and carried out proof of principle experiments; however, the sensor was too large to be mounted on an endoscope. This study designed three‐dimensional (3D) microfluidic channels encapsulating liquid metal to develop a sensor that is small enough to be mounted on an endoscope. Eight polydimethyl siloxane layers with channel structures were assembled and filled with Galinstan, a commercial liquid metal, to form 3D electrodes. The sensor was experimentally characterised and verified to be applicable to endoscopic palpation.
Synthesis and Resolution of a Chiral Diamine: 2,2′-(Propane-2,2-diyl)dipyrrolidine
Authors: Kirsch Stefan , Kotthaus Andreas , Ballaschk Frederic , Stakaj Vjoni , Mohr Fabian
Published: May 2017

A short and practical synthesis of a new chiral dipyrrolidine is presented. The three-step route includes a hydrogenation and a resolution with mandelic acid, which easily affords large quantities of the title compound.
Regioselective and Transition-Metal-Free Addition of tert-Butyl Magnesium Reagents to Pyridine Derivatives: A Convenient Method for the Synthesis of 3-Substituted 4-tert-Butylpyridine Derivatives
Authors: Rappenglück Sebastian , Niessen Karin , Seeger Thomas , Worek Franz , Thiermann Horst , Wanner Klaus
Published: May 2017

A variety of 3,4-disubstituted pyridine derivatives with a tert-butyl group in the 4-position were synthesized in a transition-metal-free, two-step reaction sequence from 3-substituted pyridine precursors. Highly regioselective addition of t-Bu2Mg to TIPS-activated pyridines and an efficient microwave-assisted aromatization with sulfur as oxidant afforded the desired 3,4-disubstituted pyridine derivatives in moderate to excellent yields. The method is compatible with many functional groups such as ester, amide, halide, nitrile or alkyne groups present in the 3-position.
Ein positiver ANA/ANCA-Befund – es muss nicht immer eine Kollagenose sein
Authors: Mayet Werner-Johannes
Published: May 2017

Der Nachweis von Autoantikörpern ist mittlerweile essentieller Bestandteil der rheumatologischen Routinediagnostik von Kollagenosen bzw. Vaskulitiden. Dies gilt besonders für antinukleäre Antikörper (ANA) und anti-neutrophile zytoplasmatische Antikörper (ANCA). Da diese Antikörperspezifitäten jedoch auch bei gastroenterologischen Erkrankungen gefunden werden, sind durchaus Fehlinterpretationen möglich. So kann bspw. eine falsche Zuordnung eines Antikörperbefundes im Rahmen einer Virushepatitis zu einem für die gastroenterologische Grunderkrankung ungünstigen Einsatz von Immunsuppressiva führen. Um auf der sicheren Seite zu sein, ist also eine genaue Kenntnis der differenzialdiagnostischen Abgrenzung von ANA und ANCA Befunden in der Rheumatologie und Gastroenterologie notwendig.
Synthesis and Characterization of new Azecine-Derivatives as Potential Neuroleptics
Authors: Zergiebel Stephanie , Fleck Christian , Arndt Hans-Dieter , Enzensperger Christoph , Seeling Andreas
Published: May 2017

Dibenzo- and benzindolo-azecines represent a class of potential neuroleptics. To characterize the effectiveness at the dopamine and 5-HT2A-receptor representative structures were synthesized and tested by radio ligand binding studies, in vivo and in vitro studies.

Neuroleptic potency and the risk of side effects of the prodrug 7-methyl-5,6,7,8,9,14-hexahydrodibenzo[d,g]azecin-3-yl isobutyrate, an ester derivative of the most promising azecine 7-methyl-5,6,7,8,9,14-hexahydrodibenzo[d,g]azecin-3-ol (LE404), was tested in vivo concerning conditioned avoidance response inhibition, locomotor activity and triggering of catalepsy vs. haloperidol as a reference. Also ester hydrolysis was examined using porcine liver esterase to thereby obtain an indication of the stability of the prodrug in vivo. An HPLC method was developed for purity control and determination of octanol/water-distribution coefficients.

It has been shown that the tested substances in their efficacy are comparable to haloperidol and risperidone, but the therapeutic index in most cases is larger. Esterification as a prodrug principle leads to significantly prolonged effectiveness.
Klinisch-praktische Prüfungen in der orthopädischen Lehre: Wer ist der „ideale“ Prüfer?
Authors: Melcher Peter , Roth Andreas , Ghanem Mohamed , Rotzoll Daisy
Published: May 2017

Hintergrund Die ärztliche Ausbildung fordert in zunehmendem Maße einen hohen Anteil an Praxis im Studium. An vielen medizinischen Fakultäten in Deutschland wird mittlerweile die OSCE-Prüfung (OSCE: objective structured clinical examination) eingesetzt, um praktische Fertigkeiten sowie Lernziele der Arzt-Patienten-Kommunikation zu überprüfen. Die Vermittlung praktischer Fertigkeiten wird zunehmend unterstützt durch Einsatz von Simulatoren- und Simulationspatiententraining unter Einsatz des sog. „Peer-Teaching“-Verfahrens durch geschulte studentische Tutoren. In dieser Arbeit wird erstmalig der Einsatz von studentischen Tutoren als Prüfer in der OSCE-Prüfung Orthopädie dahingehend überprüft, ob unterschiedliche Bewertungen der Leistung durch einen Hochschullehrer oder studentischen Tutor erfolgen.

Material und Methoden Prospektiv wurden die Daten von n = 94 aus n = 324 Studierenden des 5. Fachsemesters erhoben, die im März/April 2016 der OSCE-Station „Untersuchung der Wirbelsäule“ zurandomisiert wurden. Eine strukturierte Checkliste wurde hierzu entworfen und die beiden Prüfer (ein Hochschullehrer des Fachbereichs Orthopädie, ein studentischer Tutor) entsprechend geschult. Die Checkliste wurde von beiden Prüfern unabhängig voneinander ausgefüllt und anschließend einer statistischen Auswertung zugeführt. Die Auswertung nach Gesamtpunkten, Bewertungsblöcken und Prüfungstagen erfolgte mittels SPSS.

Ergebnisse Die durchschnittlich erreichte Punktzahl in der Gesamtbewertung lag bei 19,5 Punkten (maximal zu erreichende Punktzahl: 25), wobei der studentische Prüfer im Mittel 19,1 Punkte (SD ± 3,2), der Hochschullehrer 19,9 Punkte (SD ± 3,4) vergab. Signifikante Unterschiede in der Bewertung zeigten sich an Prüfungstag 1 (p < 0,001) und in der Gesamtauswertung (p < 0,001), während an den Prüfungstagen 2 und 3 einzeln betrachtet keine signifikanten Unterschiede zu vermerken waren.

Schlussfolgerung Die Untersuchung zeigt lediglich an Tag 1 der Prüfung eine signifikant strengere Bewertung durch den studentischen Tutor. Bei einer Punktedifferenz von 0,8 aus 25 Punkten im Mittel und einer Interrater-Reliabilität von 0,95 kann aus Sicht der Autoren eine OSCE-Prüfungsstation zur Bewertung von Untersuchungstechniken und Arzt-Patienten-Kommunikation in der Orthopädie nach entsprechender Schulung durch einen studentischen Tutor erfolgen. Grundvoraussetzung hierfür ist eine fundierte Schulung des studentischen Prüfers sowie die Entwicklung einer gut strukturierten und validierten Checkliste. Ebenso sollte eine stetige Plausibilitätsprüfung der Prüfungsergebnisse erfolgen.
Highly efficient evaluation of a gas mixer using a hollow waveguide based laser spectral sensor
Authors: Du Z. , Yang X. , Li J. , Yang Y. , Qiao C.
Published: May 2017

This paper aims to provide a fast, sensitive, and accurate characterization of a Mass Flow Controller (MFC) based gas mixer. The gas mixer was evaluated by using a hollow waveguide based laser spectral sensor with high efficiency. Benefiting from the sensor’s fast response, high sensitivity and continuous operation, multiple key parameters of the mixer, including mixing uncertainty, linearity, and response time, were acquired by a one-round test. The test results show that the mixer can blend multi-compound gases quite efficiently with an uncertainty of 1.44% occurring at a flow rate of 500 ml/min, with the linearity of 0.998 43 and the response time of 92.6 s. The results’ reliability was confirmed by the relative measurement of gas concentration, in which the isolation of the sensor’s uncertainty was conducted. The measured uncertainty has shown well coincidence with the theoretical uncertainties of the mixer, which proves the method to be a reliable characterization. Consequently, this sort of laser based characterization’s wide appliance on gas analyzer’s evaluations is demonstrated.