bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal dynamics of choice behavior in rats and humans: an examination of pre- and post-choice latencies
Authors: Fam Justine , Westbrook Fred , Arabzadeh Ehsan
Published: February 2016

Identifying similarities and differences in choice behavior across species is informative about how basic mechanisms give rise to more complex processes. In the present study, we compared pre- and post-choice latencies between rats and humans under two paradigms. In Experiment 1, we used a cued choice paradigm where subjects were presented with a cue that directed them as to which of two options to respond for rewards. In Experiment 2, subjects were free to choose between two options in order to procure rewards. In both Experiments rewards were delivered with distinct probabilities. The trial structure used in these experiments allowed the choice process to be decomposed into pre- and post-choice processes. Overall, post-choice latencies reflected the difference in reward probability between the two options, where latencies for the option with higher probability of reward were longer than those for the option with lower probability of reward. An interesting difference between rats and humans was observed: the choice behavior for humans, but not rats, was sensitive to the free-choice aspect of the tasks, such that in free-choice trials post-choice latencies no longer reflected the difference in reward probabilities between the two options.
The Indispensable Role of Cyclin-Dependent Kinase 1 in Skeletal Development
Authors: Saito Masanori , Mulati Mieradili , Talib S. Zakiah A. , Kaldis Philipp , Takeda Shu , Okawa Atsushi , Inose Hiroyuki
Published: February 2016

Skeletal development is tightly regulated through the processes of chondrocyte proliferation and differentiation. Although the involvement of transcription and growth factors on the regulation of skeletal development has been extensively studied, the role of cell cycle regulatory proteins in this process remains elusive. To date, through cell-specific loss-of-function experiments in vivo, no cell cycle regulatory proteins have yet been conclusively shown to regulate skeletal development. Here, we demonstrate that cyclin-dependent kinase 1 (Cdk1) regulates skeletal development based on chondrocyte-specific loss-of-function experiments performed in a mouse model. Cdk1 is highly expressed in columnar proliferative chondrocytes and is greatly downregulated upon differentiation into hypertrophic chondrocytes. Cdk1 is essential for proper chondrocyte proliferation and deletion of Cdk1 resulted in accelerated differentiation of chondrocytes. In vitro and ex vivo analyses revealed that Cdk1 is an essential cell cycle regulatory protein for parathyroid hormone-related peptide (PTHrP) signaling pathway, which is critical to chondrocyte proliferation and differentiation. These results demonstrate that Cdk1 functions as a molecular switch from proliferation to hypertrophic differentiation of chondrocytes and thus is indispensable for skeletal development. Given the availability of inhibitors of Cdk1 activity, our results could provide insight for the treatment of diseases involving abnormal chondrocyte proliferation, such as osteoarthritis.
Vacuum template synthesis of multifunctional nanotubes with tailored nanostructured walls
Authors: Filippin A. Nicolas , Macias-Montero Manuel , Saghi Zineb , Idígoras Jesús , Burdet Pierre , Barranco Angel , Midgley Paul , Anta Juan A. , Borras Ana
Published: February 2016

A three-step vacuum procedure for the fabrication of vertical TiO2 and ZnO nanotubes with three dimensional walls is presented. The method combines physical vapor deposition of small-molecules, plasma enhanced chemical vapor deposition of inorganic functional thin films and layers and a post-annealing process in vacuum in order to remove the organic template. As a result, an ample variety of inorganic nanotubes are made with tunable length, hole dimensions and shapes and tailored wall composition, microstructure, porosity and structure. The fabrication of multishell nanotubes combining different semiconducting oxides and metal nanoparticles is as well explored. This method provides a feasible and reproducible route for the fabrication of high density arrays of vertically alligned nanotubes on processable substrates. The emptying mechanism and microstructure of the nanotubes have been elucidated through SEM, STEM, HAADF-STEM tomography and energy dispersive X-ray spectroscopy. In this article, as a proof of concept, it is presented the straightforward integration of ZnO nanotubes as photoanode in a photovoltaic cell and as a photonic oxygen gas sensor.
Nanometer resolution optical coherence tomography using broad bandwidth XUV and soft x-ray radiation
Authors: Fuchs Silvio , Rödel Christian , Blinne Alexander , Zastrau Ulf , Wünsche Martin , Hilbert Vinzenz , Glaser Leif , Viefhaus Jens , Frumker Eugene , Corkum Paul , Förster Eckhart , Paulus Gerhard G.
Published: February 2016

Optical coherence tomography (OCT) is a non-invasive technique for cross-sectional imaging. It is particularly advantageous for applications where conventional microscopy is not able to image deeper layers of samples in a reasonable time, e.g. in fast moving, deeper lying structures. However, at infrared and optical wavelengths, which are commonly used, the axial resolution of OCT is limited to about 1 μm, even if the bandwidth of the light covers a wide spectral range. Here, we present extreme ultraviolet coherence tomography (XCT) and thus introduce a new technique for non-invasive cross-sectional imaging of nanometer structures. XCT exploits the nanometerscale coherence lengths corresponding to the spectral transmission windows of, e.g., silicon samples. The axial resolution of coherence tomography is thus improved from micrometers to a few nanometers. Tomographic imaging with an axial resolution better than 18 nm is demonstrated for layer-type nanostructures buried in a silicon substrate. Using wavelengths in the water transmission window, nanometer-scale layers of platinum are retrieved with a resolution better than 8 nm. XCT as a nondestructive method for sub-surface tomographic imaging holds promise for several applications in semiconductor metrology and imaging in the water window.
Boosting the Transparency of Thin Layers by Coatings of Opposing Susceptibility: How Metals Help See Through Dielectrics
Authors: Shakhs Mohammed Al , Augusto Lucian , Markley Loïc , Chau Kenneth J.
Published: February 2016

We propose a hypothesis that a very thin layer can be made more transparent by adding a thin coating with susceptibility of opposing sign. Two experimental tests backed by a theoretical model support this hypothesis. First, we show that the visible and near-infrared transmission through a semi-transparent silver film can be enhanced by up to ~70% and spectrally tailored depending on the type and thickness of the dielectric coating. Material types explored as dielectric coating layers include conventional metal oxides (titanium dioxide) and lesser-explored elemental semiconductors (undoped silicon, p-type silicon and germanium). Second and more surprisingly, we show that coating a 50-nm-thick silicon nitride membrane with a 10-nm-thick silver layer can modestly enhance the transmission by up to 6 ± 1% in the blue part of the spectrum. Transmission enhancements are observed for three silver-coated membranes in different configurations. Thinner silver coatings are theoretically capable of enhancement factors greater than 10%, but implementation is restricted by challenges in making smooth and continuous silver films below 10 nm in thickness. This study is important because it is the first demonstration of reciprocity with respect to the transmission enhancements achieved by combining thin metallic and dielectric layers.
Doped and undoped graphene platforms: the influence of structural properties on the detection of polyphenols
Authors: Chng Chu’Er , Sofer Zdenek , Pumera Martin , Bonanni Alessandra
Published: February 2016

There is a huge interest in doped graphene and how doping can tune the material properties for the specific application. It was recently demonstrated that the effect of doping can have different influence on the electrochemical detection of electroactive probes, depending on the analysed probe, on the structural characteristics of the graphene materials and on the type and amount of heteroatom used for the doping. In this work we wanted to investigate the effect of doping on graphene materials used as platform for the detection of catechin, a standard probe which is commonly used for the measurement of polyphenols in food and beverages. To this aim we compared undoped graphene with boron-doped graphene and nitrogen doped graphene platforms for the electrochemical detection of standard catechin oxidation. Finally, the material providing the best electrochemical performance was employed for the analysis of real samples. We found that the undoped graphene, possessing lower amount of oxygen functionalities, higher density of defects and larger electroactive surface area provided the best electroanalytical performance for the determination of catechin in commercial beer samples. Our findings are important for the development of novel graphene platforms for the electrochemical assessment of food quality.
Standardizing Flow Cytometry Immunophenotyping Analysis from the Human ImmunoPhenotyping Consortium
Authors: Finak Greg , Langweiler Marc , Jaimes Maria , Malek Mehrnoush , Taghiyar Jafar , Korin Yael , Raddassi Khadir , Devine Lesley , Obermoser Gerlinde , Pekalski Marcin L. , Pontikos Nikolas , Diaz Alain , Heck Susanne , Villanova Federica , Terrazzini Nadia , Kern Florian , Qian Yu , Stanton Rick , Wang Kui , Brandes Aaron , Ramey John , Aghaeepour Nima , Mosmann Tim , Scheuermann Richard H. , Reed Elaine , Palucka Karolina , Pascual Virginia , Blomberg Bonnie B. , Nestle Frank , Nussenblatt Robert B. , Brinkman Ryan Remy , Gottardo Raphael , Maecker Holden , McCoy J Philip
Published: February 2016

Standardization of immunophenotyping requires careful attention to reagents, sample handling, instrument setup, and data analysis, and is essential for successful cross-study and cross-center comparison of data. Experts developed five standardized, eight-color panels for identification of major immune cell subsets in peripheral blood. These were produced as pre-configured, lyophilized, reagents in 96-well plates. We present the results of a coordinated analysis of samples across nine laboratories using these panels with standardized operating procedures (SOPs). Manual gating was performed by each site and by a central site. Automated gating algorithms were developed and tested by the FlowCAP consortium. Centralized manual gating can reduce cross-center variability, and we sought to determine whether automated methods could streamline and standardize the analysis. Within-site variability was low in all experiments, but cross-site variability was lower when central analysis was performed in comparison with site-specific analysis. It was also lower for clearly defined cell subsets than those based on dim markers and for rare populations. Automated gating was able to match the performance of central manual analysis for all tested panels, exhibiting little to no bias and comparable variability. Standardized staining, data collection, and automated gating can increase power, reduce variability, and streamline analysis for immunophenotyping.
High C3 photosynthetic capacity and high intrinsic water use efficiency underlies the high productivity of the bioenergy grass Arundo donax
Authors: Webster Richard J. , Driever Steven M. , Kromdijk Johannes , McGrath Justin , Leakey Andrew D. B. , Siebke Katharina , Demetriades-Shah Tanvir , Bonnage Steve , Peloe Tony , Lawson Tracy , Long Stephen P.
Published: February 2016

Arundo donax has attracted interest as a potential bioenergy crop due to a high apparent productivity. It uses C3 photosynthesis yet appears competitive with C4 grass biomass feedstock’s and grows in warm conditions where C4 species might be expected to be that productive. Despite this there has been no systematic study of leaf photosynthetic properties. This study determines photosynthetic and photorespiratory parameters for leaves in a natural stand of A. donax growing in southern Portugal. We hypothesise that A. donax has a high photosynthetic potential in high and low light, stomatal limitation to be small and intrinsic water use efficiency unusually low. High photosynthetic rates in A. donax resulted from a high capacity for both maximum Rubisco (Vc,max 117 μmol CO2 m−2 s−1) and ribulose-1:5-bisphosphate limited carboxylation rate (Jmax 213 μmol CO2 m−2 s−1) under light-saturated conditions. Maximum quantum yield for light-limited CO2 assimilation was also high relative to other C3 species. Photorespiratory losses were similar to other C3 species under the conditions of measurement (25%), while stomatal limitation was high (0.25) resulting in a high intrinsic water use efficiency. Overall the photosynthetic capacity of A. donax is high compared to other C3 species and comparable to C4 bioenergy grasses.
Gastric microbiota and predicted gene functions are altered after subtotal gastrectomy in patients with gastric cancer
Authors: Tseng Ching-Hung , Lin Jaw-Town , Ho Hsiu J. , Lai Zi-Lun , Wang Chang-Bi , Tang Sen-Lin , Wu Chun-Ying
Published: February 2016

Subtotal gastrectomy (i.e., partial removal of the stomach), a surgical treatment for early-stage distal gastric cancer, is usually accompanied by highly selective vagotomy and Billroth II reconstruction, leading to dramatic changes in the gastric environment. Based on accumulating evidence of a strong link between human gut microbiota and host health, a 2-year follow-up study was conducted to characterize the effects of subtotal gastrectomy. Gastric microbiota and predicted gene functions inferred from 16S rRNA gene sequencing were analyzed before and after surgery. The results demonstrated that gastric microbiota is significantly more diverse after surgery. Ralstonia and Helicobacter were the top two genera of discriminant abundance in the cancerous stomach before surgery, while Streptococcus and Prevotella were the two most abundant genera after tumor excision. Furthermore, N-nitrosation genes were prevalent before surgery, whereas bile salt hydrolase, NO and N2O reductase were prevalent afterward. To our knowledge, this is the first report to document changes in gastric microbiota before and after surgical treatment of stomach cancer.
Climate and Fuel Controls on North American Paleofires: Smoldering to Flaming in the Late-glacial-Holocene Transition
Authors: Han Y.M. , Peteet D.M. , Arimoto R. , Cao J.J. , An Z.S. , Sritrairat S. , Yan B.Z.
Published: February 2016

Smoldering and flaming fires, which emit different proportions of organic (OC) and black carbon (BC, in the form of char and soot), have long been recognized in modern wildfire observations but never in a paleo-record, and little is known about their interactions with climate. Here we show that in the late glacial-early Holocene transition period, when the climate was moist, relatively high quantities of char were deposited in Linsley Pond, Connecticut, USA while soot was more abundant during the warmer and drier early Holocene interval. The highest soot mass accumulation rates (MARs) occurred at the beginning of the Holocene as fuel availability increased through the climatic transition when boreal forests were locally extirpated. These variations with time are related to the different formation pathways of char and soot, which are governed by combustion efficiency. This study provides an approach for differentiating smoldering from flaming combustion in paleo-wildfire reconstructions. Our results suggest that climate and fuel loads control the occurrence of different wildfire types and precipitation may play a key role.
Anisotropic structural and optical properties of semi-polar (11–22) GaN grown on m-plane sapphire using double AlN buffer layers
Authors: Zhao Guijuan , Wang Lianshan , Yang Shaoyan , Li Huijie , Wei Hongyuan , Han Dongyue , Wang Zhanguo
Published: February 2016

We report the anisotropic structural and optical properties of semi-polar (11–22) GaN grown on m-plane sapphire using a three-step growth method which consisted of a low temperature AlN buffer layer, followed by a high temperature AlN buffer layer and GaN growth. By introducing double AlN buffer layers, we substantially improve the crystal and optical qualities of semi-polar (11–22) GaN and significantly reduce the density of stacking faults and dislocations. The high resolution x-ray diffraction measurement revealed that the in-plane anisotropic structural characteristics of GaN layer are azimuthal dependent. Transmission electron microscopy analysis showed that the majority of dislocations in the GaN epitaxial layer grown on m-sapphire are the mixed-type and the orientation of GaN layer was rotated 58.4° against the substrate. The room temperature photoluminescence (PL) spectra showed the PL intensity and wavelength have polarization dependence along parallel and perpendicular to the [1–100] axis (polarization degrees ~ 0.63). The realization of a high polarization semi-polar GaN would be useful to achieve III-nitride based lighting emission device for displays and backlighting.
Complex-shaped three-dimensional multi-compartmental microparticles generated by diffusional and Marangoni microflows in centrifugally discharged droplets
Authors: Hayakawa Masayuki , Onoe Hiroaki , Nagai Ken H. , Takinoue Masahiro
Published: February 2016

We report a versatile method for the generation of complex-shaped three-dimensional multi-compartmental (3D-MC) microparticles. Complex-shaped microparticles have recently received much attention for potential application in self-assemblies, micromachines and biomedical and environmental engineering. Here, we have developed a method based on 3D nonequilibrium-induced microflows (Marangoni and diffusional flows) of microdroplets that are discharged from the tip of a thin capillary in a simple centrifugal microfluidic device. The microparticle shapes can be tuned by the partial dissolution of specific compartments and by the deformation of the precursor microdroplets by manipulating the 3D microflows. We believe that this method will have wide applications in nano- and microscience and technologies.
Structure-Property-Function Relationship in Humic Substances to Explain the Biological Activity in Plants
Authors: García Andrés Calderín , de Souza Luiz Gilberto Ambrosio , Pereira Marcos Gervasio , Castro Rosane Nora , García-Mina José María , Zonta Everaldo , Lisboa Francy Junior Gonçalves , Berbara Ricardo Luis Louro
Published: February 2016

Knowledge of the structure-property-function relationship of humic substances (HSs) is key for understanding their role in soil. Despite progress, studies on this topic are still under discussion. We analyzed 37 humic fractions with respect to their isotopic composition, structural characteristics, and properties responsible for stimulating plant root parameters. We showed that regardless of the source of origin of the carbon (C3or C4), soil-extracted HSs and humic acids (HAs) are structurally similar to each other. The more labile and functionalized HS fraction is responsible for root emission, whereas the more recalcitrant and less functionalized HA fraction is related to root growth. Labile structures promote root stimulation at lower concentrations, while recalcitrant structures require higher concentrations to promote a similar stimulus. These findings show that lability and recalcitrance, which are derived properties of humic fractions, are related to the type and intensity of their bioactivity. In summary, the comparison of humic fractions allowed a better understanding of the relationship between the source of origin of plant carbon and the structure, properties, and type and intensity of the bioactivity of HSs in plants. In this study, scientific concepts are unified and the basis for the agronomic use of HSs is established.
PFR peptide, one of the antimicrobial peptides identified from the derivatives of lactoferrin, induces necrosis in leukemia cells
Authors: Lu Yan , Zhang Teng-Fei , Shi Yue , Zhou Han-Wei , Chen Qi , Wei Bu-Yun , Wang Xi , Yang Tian-Xin , Chinn Y. Eugene , Kang Jian , Fu Cai-Yun
Published: February 2016

LF11-322 (PFWRIRIRR-NH2) (PFR peptide), a nine amino acid-residue peptide fragment derived from human lactoferricin, possesses potent cytotoxicity against bacteria. We report here the discovery and characterization of its antitumor activity in leukemia cells. PFR peptide inhibited the proliferation of MEL and HL-60 leukemia cells by inducing cell death in the absence of the classical features of apoptosis, including chromatin condensation, Annexin V staining, Caspase activation and increase of abundance of pro-apoptotic proteins. Instead, necrotic cell death as evidenced by increasing intracellular PI staining and LDH release, inducing membrane disruption and up-regulating intracellular calcium level, was observed following PFR peptide treatment. In addition to necrotic cell death, PFR peptide also induced G0/G1 cell cycle arrest. Moreover, PFR peptide exhibited favorable antitumor activity and tolerability in vivo. These findings thus provide a new clue of antimicrobial peptides as a potential novel therapy for leukemia.
Impact of different cell penetrating peptides on the efficacy of antisense therapeutics for targeting intracellular pathogens
Authors: Abushahba Mostafa F. N. , Mohammad Haroon , Thangamani Shankar , Hussein Asmaa A. A. , Seleem Mohamed N.
Published: February 2016

There is a pressing need for novel and innovative therapeutic strategies to address infections caused by intracellular pathogens. Peptide nucleic acids (PNAs) present a novel method to target intracellular pathogens due to their unique mechanism of action and their ability to be conjugated to cell penetrating peptides (CPP) to overcome challenging delivery barriers. In this study, we targeted the RNA polymerase α subunit (rpoA) using a PNA that was covalently conjugated to five different CPPs. Changing the conjugated CPP resulted in a pronounced improvement in the antibacterial activity observed against Listeria monocytogenes in vitro, in cell culture and in a Caenorhabditis elegans (C. elegans) infection model. Additionally, a time-kill assay revealed three conjugated CPPs rapidly kill Listeria within 20 minutes without disrupting the bacterial cell membrane. Moreover, rpoA gene silencing resulted in suppression of its message as well as reduced expression of other critical virulence genes (Listeriolysin O and two phospholipases plcA and plcB) in a concentration-dependent manner. Furthermore, PNA-inhibition of bacterial protein synthesis was selective and did not adversely affect mitochondrial protein synthesis. This study provides a foundation for improving and developing PNAs conjugated to CPPs to better target intracellular pathogens.
Differential Expression of Genes and DNA Methylation associated with Prenatal Protein Undernutrition by Albumen Removal in an avian model
Authors: Willems Els , Guerrero-Bosagna Carlos , Decuypere Eddy , Janssens Steven , Buyse Johan , Buys Nadine , Jensen Per , Everaert Nadia
Published: February 2016

Previously, long-term effects on body weight and reproductive performance have been demonstrated in the chicken model of prenatal protein undernutrition by albumen removal. Introduction of such persistent alterations in phenotype suggests stable changes in gene expression. Therefore, a genome-wide screening of the hepatic transcriptome by RNA-Seq was performed in adult hens. The albumen-deprived hens were created by partial removal of the albumen from eggs and replacement with saline early during embryonic development. Results were compared to sham-manipulated hens and non-manipulated hens. Grouping of the differentially expressed (DE) genes according to biological functions revealed the involvement of processes such as ‘embryonic and organismal development’ and ‘reproductive system development and function’. Molecular pathways that were altered were ‘amino acid metabolism’, ‘carbohydrate metabolism’ and ‘protein synthesis’. Three key central genes interacting with many DE genes were identified: UBC, NR3C1, and ELAVL1. The DNA methylation of 9 DE genes and 3 key central genes was examined by MeDIP-qPCR. The DNA methylation of a fragment (UBC_3) of the UBC gene was increased in the albumen-deprived hens compared to the non-manipulated hens. In conclusion, these results demonstrated that prenatal protein undernutrition by albumen removal leads to long-term alterations of the hepatic transcriptome in the chicken.
Onset and duration of transitions into Greenland Interstadials 15.2 and 14 in northern China constrained by an annually laminated stalagmite
Authors: Duan Wuhui , Cheng Hai , Tan Ming , Edwards R. Lawrence
Published: February 2016

The onset and duration of abrupt transitions into Dansgaard-Oeschger (DO) events can be studied in detail in Greenland ice cores given the excellent relative uncertainty of its lamina-counting chronology. For other geological archives, however, the shorter intervals are not determined accurately due to lack of clear annual lamina. Here, we present an oxygen isotope record of a stalagmite with well-developed annual lamina from Xinglong Cave, northern China, covering DO 15 and 14. Except for the absence of Greenland Interstadial (GIS) 15.1, the pattern of this record strongly resembles that of Greenland ice cores on millennial scales as well as the detailed centennial-scale cooling excursions within GIS 14. Additionally, the transitions into GIS 15.2 and 14, constrained by lamina counting, lasted 74 and 27 yr, respectively, both of which are in excellent agreement with that of the NGRIP record on the GICC05 timescales (100 ± 6 and 20 ± 1 yr, respectively). The close coupling of abrupt climatic oscillations on millennial to decadal scales between Greenland and northern China implies a rapid atmospheric teleconnection between the North Atlantic and the East Asian Summer Monsoon regions, probably via the westerlies.
The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds
Authors: Pusnik Mascha , Imeri Minire , Deppierraz Grégoire , Bruinink Arie , Zinn Manfred
Published: February 2016

A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds and this at higher sensitivity and in a quantitative way.
Carrier density independent scattering rate in SrTiO3-based electron liquids
Authors: Mikheev Evgeny , Raghavan Santosh , Zhang Jack Y. , Marshall Patrick B. , Kajdos Adam P. , Balents Leon , Stemmer Susanne
Published: February 2016

We examine the carrier density dependence of the scattering rate in two- and three-dimensional electron liquids in SrTiO3 in the regime where it scales with Tn (T is the temperature and n ≤ 2) in the cases when it is varied by electrostatic control and chemical doping, respectively. It is shown that the scattering rate is independent of the carrier density. This is contrary to the expectations from Landau Fermi liquid theory, where the scattering rate scales inversely with the Fermi energy (EF). We discuss that the behavior is very similar to systems traditionally identified as non-Fermi liquids (n < 2). This includes the cuprates and other transition metal oxide perovskites, where strikingly similar density-independent scattering rates have been observed. The results indicate that the applicability of Fermi liquid theory should be questioned for a much broader range of correlated materials and point to the need for a unified theory.
Thickness scaling of atomic-layer-deposited HfO2 films and their application to wafer-scale graphene tunnelling transistors
Authors: Jeong Seong-Jun , Gu Yeahyun , Heo Jinseong , Yang Jaehyun , Lee Chang-Seok , Lee Min-Hyun , Lee Yunseong , Kim Hyoungsub , Park Seongjun , Hwang Sungwoo
Published: February 2016

The downscaling of the capacitance equivalent oxide thickness (CET) of a gate dielectric film with a high dielectric constant, such as atomic layer deposited (ALD) HfO2, is a fundamental challenge in achieving high-performance graphene-based transistors with a low gate leakage current. Here, we assess the application of various surface modification methods on monolayer graphene sheets grown by chemical vapour deposition to obtain a uniform and pinhole-free ALD HfO2 film with a substantially small CET at a wafer scale. The effects of various surface modifications, such as N-methyl-2-pyrrolidone treatment and introduction of sputtered ZnO and e-beam-evaporated Hf seed layers on monolayer graphene, and the subsequent HfO2 film formation under identical ALD process parameters were systematically evaluated. The nucleation layer provided by the Hf seed layer (which transforms to the HfO2 layer during ALD) resulted in the uniform and conformal deposition of the HfO2 film without damaging the graphene, which is suitable for downscaling the CET. After verifying the feasibility of scaling down the HfO2 thickness to achieve a CET of ~1.5 nm from an array of top-gated metal-oxide-graphene field-effect transistors, we fabricated graphene heterojunction tunnelling transistors with a record-low subthreshold swing value of <60 mV/dec on an 8″ glass wafer.
MiR218 Modulates Wnt Signaling in Mouse Cardiac Stem Cells
by Promoting Proliferation and Inhibiting Differentiation through a Positive Feedback
Loop
Authors: Wang Yongshun , Liu Jingjin , Cui Jinjin , Sun Meng , Du Wenjuan , Chen Tao , Ming Xing , Zhang Lulu , Tian Jiangtian , Li Ji , Yin Li , Liu Fang , Pu Zhongyue , Lv Bo , Hou Jingbo , Yu Bo
Published: February 2016

MiRNA expression was determined in both proliferating and differentiated cardiac
stem cells (CSCs) through a comprehensive miRNA microarray analysis. We selected
miR218 for functional follow-up studies to examine its significance in CSCs. First,
we observed that the expression of miR218 was altered in CSCs during differentiation
into cardiomyocytes and transfection of an miR218 mimic or miR218 inhibitor affected
the myocardial differentiation of CSCs. Furthermore, we observed that a negative
regulator of Wnt signaling, sFRP2, was a direct target of miR218 and the protein
levels of sFRP2 were increased in cells transfected with the synthetic miR218
inhibitor. In contrast, transfection with the miR218 mimic decreased the expression
of sFRP2 and potentiated Wnt signaling. The subsequent down-regulation of sFRP2 by
shRNA potentiated Wnt signaling, contributing to a gene expression program that is
important for CSC proliferation and cardiac differentiation. Specifically, canonical
Wnt signaling induced miR218 transcription. Thus, miR218 and Wnt signaling were
coupled through a feed-forward positive feedback loop, forming a biological
regulatory circuit. Together, these results provide the first evidence that miR218
plays an important role in CSC proliferation and differentiation through the
canonical Wnt signaling pathway.
Upper Critical Field and Kondo Effects in Fe(Te0.9Se0.1) Thin Films by Pulsed Field Measurements
Authors: Salamon Myron B. , Cornell Nicholas , Jaime Marcelo , Balakirev Fedor F. , Zakhidov Anvar , Huang Jijie , Wang Haiyan
Published: February 2016

The transition temperatures of epitaxial films of Fe(Te0:9Se0:1) are remarkably insensitive to applied magnetic field, leading to predictions of upper critical fields Bc2(T = 0) in excess of 100 T. Using pulsed magnetic fields, we find Bc2(0) to be on the order of 45 T, similar to values in bulk material and still in excess of the paramagnetic limit. The same films show strong magnetoresistance in fields above Bc2(T), consistent with the observed Kondo minimum seen above Tc. Fits to the temperature dependence in the context of the WHH model, using the experimental value of the Maki parameter, require an effective spin-orbit relaxation parameter of order unity. We suggest that Kondo localization plays a similar role to spin-orbit pair breaking in making WHH fits to the data.
An Efficient LCM-Based Method for Tissue Specific Expression Analysis of Genes and miRNAs
Authors: Gautam Vibhav , Singh Archita , Singh Sharmila , Sarkar Ananda K.
Published: February 2016

Laser Capture Microdissection (LCM) is a powerful tool to isolate and study gene expression pattern of desired and less accessible cells or tissues from a heterogeneous population. Existing LCM-based methods fail to obtain high quality RNA including small RNAs from small microdissected plant tissue and therefore, are not suitable for miRNA expression studies. Here, we describe an efficient and cost-effective method to obtain both high quality RNA and miRNAs from LCM-derived embryonic root apical meristematic tissue, which is difficult to access. We have significantly modified and improved the tissue fixation, processing, sectioning and RNA isolation steps and minimized the use of kits. Isolated RNA was checked for quality with bioanalyzer and used for gene expression studies. We have confirmed the presence of 19-24 nucleotide long mature miRNAs using modified stem-loop RT-PCR. This modified LCM-based method is suitable for tissue specific expression analysis of both genes and small RNAs (miRNAs).
Probing the spectral density of the surface electromagnetic fields through scattering of waveguide photons
Authors: Chen Guang-Yin
Published: February 2016

The spectral density of the metal-surface electromagnetic fields will be strongly modified in the presence of a closely-spaced quantum emitter. In this work, we propose a feasible way to probe the changes of the spectral density through the scattering of the waveguide photon incident on the quantum emitter. The variances of the lineshape in the transmission spectra indicate the coherent interaction between the emitter and the pseudomode resulting from all the surface electromagnetic modes. We further investigate the quantum coherence between the emitter and the pseudomode of the metal-dielectric interface.
Stereoselective synthesis and structural elucidation of dicarba peptides
Authors: Gleeson Ellen C. , Wang Zhen J. , Robinson Samuel D. , Chhabra Sandeep , MacRaild Christopher A. , Jackson W. Roy , Norton Raymond S. , Robinson Andrea J.
Published: February 2016

PreformedZ- andE-diaminosuberic acid residues can be used to synthesise target dicarba peptides.13C NMR spectroscopy can be used to assign stereochemistry in dicarba peptides.
Binding properties of pendimethalin herbicide to DNA: multispectroscopic and molecular docking approaches
Authors: Ahmad Irshad , Ahmad Ajaz , Ahmad Masood
Published: February 2016

Pendimethalin (PND) is a systemic herbicide widely used on rice, cotton, peas, wheat, potatoes, fruits, nuts and other residential and non-residential crops; however, it concurrently exerts toxic effects on beneficial organisms like earthworms, aquatic invertebrates and other non-targeted animals including humans.
Al atom on MoO3(010) surface: adsorption and penetration using density functional theory
Authors: Wu Hong-Zhang , Bandaru Sateesh , Wang Da , Liu Jin , Lau Woon Ming , Wang Zhenling , Li Li-Li
Published: February 2016

This study employs first-principle density functional theory to model Al/MoO3by placing an Al adatom onto a unit cell of a MoO3(010) slab, and to probe the initiation of interfacial interactions of Al/MoO3nanothermite by tracking the adsorption and subsurface-penetration of the Al adatom.
Mesoporous EU-1 zeolite as a highly active catalyst for ethylbenzene hydroisomerization
Authors: Mota F. Marques , Eliášová P. , Jung J. , Ryoo R.
Published: February 2016

The synthesis of a micro-mesoporous EUO zeolite with a significant volume of intercrystalline mesoporosity revealed an outstanding result in the challenging industrial hydroisomerization of ethylbenzene.
Synthesis of a rhodium(i) germyl complex: a useful tool for C–H and C–F bond activation reactions
Authors: Ahrens Theresia , Ahrens Mike , Braun Thomas , Braun Beatrice , Herrmann Roy
Published: February 2016

The rhodium(i) germyl complex [Rh(GePh3)(PEt3)3] is a useful tool for C–F and C–H bond activation reactions. For instance, treatment with hexafluoropropene results in the formation of two isomeric C–F activation products [Rh{(E)-CFCF(CF3)}(PEt3)3] and [Rh{(Z)-CFCF(CF3)}(PEt3)3] in a 3 : 1 ratio.
Triphos derivatives and diphosphines as ligands in the ruthenium-catalysed alcohol amination with NH3
Authors: Nakagawa N. , Derrah E. J. , Schelwies M. , Rominger F. , Trapp O. , Schaub T.
Published: February 2016

The ruthenium-triphos and diphosphine-catalysed amination of alcohols with ammonia is reported.
A non-typical sequence of phase transitions in (NH4)3GeF7: optical and structural characterization
Authors: Mel'nikova S. V. , Molokeev M. S. , Laptash N. M. , Misyul S. V.
Published: February 2016

Double salt (NH4)3GeF7 exhibits unusual tetragonal-cubic transformation on cooling.
Towards a “dry” bio-refinery without solvents or added water using microwaves and ultrasound for total valorization of fruit and vegetable by-products
Authors: Jacotet-Navarro M. , Rombaut N. , Deslis S. , Fabiano-Tixier A.-S. , Pierre F.-X. , Bily A. , Chemat F.
Published: February 2016

This study aims at total valorization of fruit and vegetable by-products, moving towards developing an original concept of “dry” bio-refinery (DBR).
New insights into the structure and composition of technical lignins: a comparative characterisation study
Authors: Constant Sandra , Wienk Hans L. J. , Frissen Augustinus E. , Peinder Peter de , Boelens Rolf , van Es Daan S. , Grisel Ruud J. H. , Weckhuysen Bert M. , Huijgen Wouter J. J. , Gosselink Richard J. A. , Bruijnincx Pieter C. A.
Published: February 2016

Multitechnique characterization of six technical lignins including nuclear magnetic resonance and size exclusion chromatography studies.
Design, synthesis, linear and nonlinear photophysical properties of novel pyrimidine-based imidazole derivatives
Authors: Zhang Qiong , Luo Lei , Xu Hong , Hu Zhangjun , Brommesson Caroline , Wu Jieying , Sun Zhaoqi , Tian Yupeng , Uvdal Kajsa
Published: February 2016

Novel pyrimidine imidazole derivatives with flexible ether chains have been synthesised and evaluated for their cell imaging performanceviaphotophysical investigations and theoretical calculations.
An efficient visible light photocatalyst based on tin porphyrin intercalated between TiO2–graphene nanosheets for inactivation of E. coli and investigation of charge transfer mechanism
Authors: Zargari S. , Rahimi R. , Yousefi A.
Published: February 2016

Tin porphyrin intercalated between the TiO2–grphene nanocomposite. The inactivation of E. coli over the prepared compound was significantly increased via the interaction of tin porphyrin between the TiO2–graphene nanocomposite.
Self-assembly of sodium and potassium betulinates into hydro- and organo-gels: entrapment and removal studies of fluorophores and synthesis of gel–gold nanoparticle hybrid materials
Authors: Bag Braja Gopal , Dash Shib Shankar
Published: February 2016

Sodium and potassium salts of a renewable nano-sized triterpenoid betulinic acid have been prepared and their self-assembly properties in water and aqueous solvent mixtures have been studied.
Fe0-activated persulfate-assisted mechanochemical destruction of expired compound sulfamethoxazole tablets
Authors: Liu Xitao , Zhang Xiaohui , Shao Kai , Lin Chunye , Li Caibin , Ge Fangzhou , Dong Yujing
Published: February 2016

Sulfamethoxazole (SMX) and trimethoprim (TMP) in compound sulfamethoxazole tablets (CSTs) can be degraded effectively by the Fe0-activated persulfate-assisted mechanochemical process.
Innovative physically-assisted soda fractionation of rapeseed hulls for better recovery of biopolymers
Authors: Brahim M. , Boussetta N. , Grimi N. , Vorobiev E. , Brosse N.
Published: February 2016

A better knowledge of the effect of non-conventional pretreatment technologies, which can avoid the use of high temperatures and detrimental solvents, is necessary.
Nano-FGT: a green and sustainable catalyst for the synthesis of spirooxindoles in aqueous medium
Authors: Jamatia Ramen , Gupta Ajay , Pal Amarta Kumar
Published: February 2016

A glutathione grafted nano-organocatalyst (nano-FGT) was used as an efficient catalyst for the synthesis of spirooxindole derivatives.
An injectable scaffold based on crosslinked hyaluronic acid gel for tissue regeneration
Authors: Yang Rui , Tan Linhua , Cen Lian , Zhang Zhibing
Published: February 2016

An injectable scaffold of crosslinked hyaluronic acid gel for tissue regeneration.
Solvent-directed sol-gel assembly of 3-dimensional graphene-tented metal oxides and strong synergistic disparities in lithium storage
Authors: Ye Jianchao , An Yonghao , Montalvo Elizabeth , Campbell Patrick G. , Worsley Marcus A. , Tran Ich C. , Liu Yuanyue , Wood Brandon C. , Biener Juergen , Jiang Hanqing , Tang Ming , Wang Y. Morris
Published: February 2016

The conversion-reaction-based metal oxide/graphene aerogels show much higher capacitive synergy than that observed for intercalation-based TiO2/graphene aerogels.
A carboxymethyl chitosan and peptide-decorated polyetheretherketone ternary biocomposite with enhanced antibacterial activity and osseointegration as orthopedic/dental implants
Authors: Xu Anxiu , Zhou Liwei , Deng Yi , Chen Xianshen , Xiong Xiaoling , Deng Feng , Wei Shicheng
Published: February 2016

A carboxymethyl chitosan and peptide-decorated PEEK ternary biocomposite showed enhanced antibacterial activity, in vitro osteogenic differentiation and in vivo osseointegration.
DC-bias dependent impedance spectroscopy of BaTiO3–Bi(Zn1/2Ti1/2)O3 ceramics
Authors: Kumar Nitish , Patterson Eric A. , Frömling Till , Cann David P.
Published: February 2016

In p-type BaTiO3, a deviation from Ohm's law behavior at low fields was noted with a significant decrease in resistivity values; whereas the response of n-type Bi(Zn1/2Ti1/2)O3-containing ceramics was insensitive to bias.
Determination of the microstructure, energy levels and magnetic dipole transition mechanism for Tm3+doped yttrium aluminum borate
Authors: Ju Meng , Kuang Xiaoyu , Lu Cheng , Li Hui , Wang Jingjing , Zhang Chuanzhao , Zhu Yongsheng , Yeung Yauyuen
Published: February 2016

Yttrium aluminum borate (YAB) doped with rare-earth ions are promising materials for infrared lasers and self-frequency summing laser systems.
Synthesis of the rare disaccharide nigerose by structure-based design of a phosphorylase mutant with altered regioselectivity
Authors: Kraus M. , Görl J. , Timm M. , Seibel J.
Published: February 2016

A Q345F exchange of sucrose phosphorylase fromBifidobacterium adolescentisalters the regioselectivity of the acceptor reaction with glucose from kojibiose (α-1,2 linked) to nigerose (α-1,3 linked).
Molecular dynamics simulations of the atom packing characteristics of three deformed silver nanoparticles at room temperature
Authors: Zhang Lin
Published: February 2016

Molecular dynamics simulations demonstrate the effects of external load and surface atoms on three silver nanoparticles with one atom difference.
Synthesis and properties of new mononuclear Ru(ii)-based photocatalysts containing 4,4′-diphenyl-2,2′-bipyridyl ligands
Authors: Coe Benjamin J. , Sánchez Sergio
Published: February 2016

Almost colourlesstrans-RuIICl2(N^N)(CO)2(N^N = a derivative of 4,4′-diphenyl-2,2′-bipyridyl) complexes are reasonably effective photocatalytic oxidants in combination with a photosensitizer and sacrificial oxidant.
Copper(ii)-catalyzed C5 and C7 halogenation of quinolines using sodium halides under mild conditions
Authors: Xu Jun , Zhu Xiaolei , Zhou Guobin , Ying Beibei , Ye Pingping , Su Lingying , Shen Chao , Zhang Pengfei
Published: February 2016

A simple and mild protocol for copper catalyzed halogenation of quinoline at C5 and C7 positions was developed, affording the desired remote C–H activation products in moderate to good yields.
Edible coating from citrus essential oil-loaded nanoemulsions: physicochemical characterization and preservation performance
Authors: Wu Chunhua , Wang Liping , Hu Yaqin , Chen Shiguo , Liu Donghong , Ye Xingqian
Published: February 2016

To improve the availability of citrus essential oil (CEOs), nanoemulsions based on chitosan nanoparticles loaded with CEOs were prepared by the emulsion-ionic gelation technique.
Application of novel triarylmethane dyes having thienyl, thieno[3,2-b]thienyl, and dithieno[3,2-b:2′,3′-d]thienyl rings as auxochromes to super acid pH sensors
Authors: Matsui Masaki , Kakitani Kenta , Kubota Yasuhiro , Funabiki Kazumasa , Ishida Masaru
Published: February 2016

Novel triarylmethane dyes decorated with 2-thienyl, 2-thieno[3,2-b]thienyl, and 2-dithieno[3,2-b:2′,3′-d]thienyl rings as auxochromes were much more bathochromic than the known crystal violet.
Smartphone based LSPR sensing platform for bio-conjugation detection and quantification
Authors: Dutta Sibasish , Saikia Koushik , Nath Pabitra
Published: February 2016

Localized surface plasmon resonance based sensing and biosensing has been performed using the camera of a smartphone.
Antimicrobial electrospun poly(ε-caprolactone) scaffolds for gingival fibroblast growth
Authors: Baranowska-Korczyc Anna , Warowicka Alicja , Jasiurkowska-Delaporte Małgorzata , Grześkowiak Bartosz , Jarek Marcin , Maciejewska Barbara M. , Jurga-Stopa Justyna , Jurga Stefan
Published: February 2016

This study discusses the value of polymer electrospun materials in three-dimensional (3D) scaffolds and antibacterial wound dressings for potential dental applications.
High thermoelectric performance of tellurium doped paracostibite
Authors: Chmielowski R. , Bhattacharya S. , Xie W. , Péré D. , Jacob S. , Stern R. , Moriya K. , Weidenkaff A. , Madsen G. K. H. , Dennler G.
Published: February 2016

Paracostibite (CoSbS) has recently been identified as a promising thermoelectric material, yet its full potential remains to be attained. By carrying out an optimization of the experimental parameters, we achieve a power factor as high as 2.7 mW m−1 K−2 at 543 K.
Optical waveguide modeling of refractive index mediated pH responses in silica nanocomposite thin film based fiber optic sensors
Authors: Ohodnicki P. R. , Wang C.
Published: February 2016

Recent experiments have demonstrated a pH-dependent optical transmission of silica based nanocomposite thin film enabled evanescent wave absorption spectroscopy based fiber optic sensors in aqueous solutions. Although the response was observed to linearly correlate with the pH-dependent surface charge density of the silica matrix, the responsible mechanism was not fully clarified. In this manuscript, an optical waveguide model is applied to describe observed responses through a modified effective refractive index of the silica matrix layer as a function of the solution phase pH. The refractive index dependence results from a surface charge dependent ionic adsorption, resulting in concentration of ionic species at charged surfaces. The resultant effective index modification to porous silica is estimated through effective medium theories and applied to an optical waveguide model of a multi-mode fiber optic based sensor response capable of reproducing all experimental observations reported to date.
Comment on “In situ imaging of ultra-fast loss of nanostructure in nanoparticle aggregates” [J. Appl. Phys. 115, 084903 (2014)]
Authors: Levitas Valery I. , Hwang Yong Seok
Published: February 2016

One of the conclusions of a recent article by Egan et al. [J. Appl. Phys. 115, 084903 (2014)] was that since the melt-dispersion mechanism (MDM) of the reaction of aluminum nanoparticles was not observed in their experiments, this mechanism is very unlikely. Our main point here is to demonstrate that, in fact, these experiments do not disprove the MDM.