bluuebunny/crossref_metadata_2025 huggingface dataset:
The proteasome enters the meiotic prophase fray
Authors: Vujin Aleksandar , Zetka Monique
Published: June 2017

The segregation of homologous chromosomes in meiosis depends on their ability to locate one another in the nucleus and establish a physical association through crossing over. A tightly regulated number of crossovers (COs) emerges following repair of induced DNA double‐strand breaks by homologous recombination (HR), but the process of how HR intermediates transition into COs is still poorly understood. Two recent studies by Ahuja et al. and Rao et al. have revealed a role for chromosomally localized proteasomes in choreographing both homologous chromosome pairing and the evolution of HR intermediates into segregation‐competent COs. Using chemical inhibition of the proteasome and mutant analysis, the collective data reveal conserved functions for both the proteasome and a family of E3 ligases that can direct or compete with its activity in ensuring CO formation. Here, we review these findings and the impact of the discovery that protein modification dynamics and proteasomal activity cooperate to regulate key meiotic processes.
A comparison of existing and novel communication responses used during functional communication training
Authors: Matter Ashley L. , Zarcone Jennifer R.
Published: June 2017

Functional communication training (FCT) is a procedure used to teach a communicative response that results in the same reinforcer found to maintain problem behavior. Previous research has demonstrated that high levels of problem behavior may be observed during FCT when reinforcing an existing response due to a history of reinforcement for both existing responses and problem behavior. This study compared the effects of reinforcing an existing and novel communicative response during FCT on the rate of problem behavior for two children diagnosed with autism. Additionally, we assessed preference for either the existing or novel response using a concurrent schedules arrangement. The results demonstrated that the existing and novel communication responses were associated with low levels of problem behavior for both participants. Also, both participants preferred the novel response. We conclude with a discussion of practical applications of the analysis and avenues for future research.
A tricorn‐rhodamine fluorescent chemosensor for detection of Co2+ ions
Authors: Li Jing , Han Shuhua
Published: June 2017

A novel chemosensor TrisRh based on tris(2‐aminoethyl)amine and rhodamine 6G is designed and synthesized as a fluorescence turn‐on probe for Co2+ ions that is paramagnetic with a property of quenching fluorescence. Rhodamine spirolactam forms are nonfluorescent, whereas, ring‐opening of corresponding spirocyclic induced by Co2+ results in strong fluorescence emission. Upon the addition of Co2+ ions, TrisRh can display significant enhancements in absorbance and fluorescence intensity as well as evident colorific transformation, which can be perceived by the naked eye. The association stoichiometry of TrisRh to Co2+ ions was inferred to be 1:1 through Job's plot and electrospray ionization mass spectrometry analysis. The binding model was speculated from Fourier transform infrared spectra and 1H–nuclear magnetic resonance technologies. Significantly, the limit of detection was determined to be as low as 1.22 nmol. Furthermore, TrisRh can exhibit robust anti‐jamming ability against other interference metal ions.
A colorimetric and fluorescent chemosensor for selective detection of Cu2+ based on a new diarylethene with a benzophenone hydrazone unit
Authors: Li Lili , Li Hui , Liu Gang , Pu Shouzhi
Published: June 2017

A new photochromic diarylethene based on benzophenone hydrazone has been synthesized. Its photochromic and fluorescent properties changed upon alternating irradiation with UV/Vis light and adding Cu2+/EDTA in methanol, which showed that the diarylethene could be served as a colorimetric and fluorescent chemosensor for selective detection of Cu2+ based on internal charge transfer processes. The colorimetric and turn‐off fluorescent selective detection of Cu2+ was attributed to the 2:1 complex of the diarylethene and Cu2+. The binding constant (Ka) was 1.53 × 104 L mol−1 and the limit of detection of the diarylethene for Cu2+ was calculated to be 1.45 × 10−6 mol L−1. In addition, the metal‐responsive photochromic behavior of diarylethene was applied successfully to the construction of a molecular logic circuit.
One‐pot synthesis of fluorescent nitrogen‐doped carbon dots with good biocompatibility for cell labeling
Authors: Zhang Zhengwei , Yan Kun , Yang Qiulian , Liu Yanhua , Yan Zhengyu , Chen Jianqiu
Published: June 2017

Here we report an easy and economical hydrothermal carbonization approach to synthesize the fluorescent nitrogen‐doped carbon dots (N‐CDs) that was developed using citric acid and triethanolamine as the precursors. The synthesis conditions were optimized to obtain the N‐CDs with superior fluorescence performances. The as‐prepared N‐CDs are monodispersed sphere nanoparticles with good water solubility, and exhibited strong fluorescence, favourable photostability and excitation wavelength‐dependent behavior. Furthermore, the in vitro cytotoxicity and cellular labeling of N‐CDs were investigated using the rat glomerular mesangial cells. The results showed the N‐CDs have more inconspicuous cytotoxicity and better biosafety in comparison with ZnSe quantum dots, although both targeted the cells successfully. Considering their admirable photostability, low toxicity and good compatibility, the as‐obtained N‐CDs could have potential applications in biosensors, cellular imaging, and other fields.
Self‐assembly of t‐butyloxycarbonyl protected dipeptide methyl esters composed of leucine, isoleucine, and valine into highly organized structures from alcohol and aqueous alcohol mixtures
Authors: Subbalakshmi Chivukula , Basak Pratyay , Nagaraj Ramakrishnan
Published: June 2017

Short peptides composed of phenylalanine and sequences derived from amyloidogenic peptides have the ability to self‐assemble to form nanostructures including hydrogels. The self‐assembly of peptides composed of only hydrophobic amino acids and aliphatic protecting groups have not been investigated in detail. We have examined various aspects of nanostructures formed by N‐terminal t‐butyloxycarbonyl‐protected aliphatic dipeptide methyl esters dissolved in various solvents. Scanning electron microscopic images indicate that depending on the sequence, position of the amino acid and solvent of dissolution, the peptides self‐assemble into superstructures such as nanotubes and needles particularly from aqueous mixtures of organic solvents. Crystallization was not required for self‐assembly into nanostructures. Circular dichroism and attenuated total internal reflection fourier transform infrared spectroscopy studies indicate that the peptides adopt β‐conformation in the superstructures both in solution and solid state. The nanostructures composed of entirely aliphatic moieties have the ability to bind to aromatic dyes such as Rhodamine 6G, Nile red and Congo red. They also bind to Thioflavin T although the structures do not resemble amyloid fibrils. The powder X‐ray diffraction patterns suggest distinctive packing of the monomers. These structures are stabilized by intermolecular hydrogen bonds and hydrophobic interactions resulting in superstructures containing long distance order and were devoid of hemolytic activity.
From physical to digital in structural engineering classrooms using digital fabrication
Authors: Chacón Rolando , Codony David , Toledo Álvaro
Published: June 2017

In this paper, a set of digital artifacts related to simple examples of structural engineering are presented. The artifacts are real‐time applications and visualizations of typical problems students from the architecture, engineering, and construction (AEC) schools are acquainted with. The real‐time nature of the examples allow a high level of interaction between humans and the classic visualization of results, namely, bending and shear force diagrams, internal stresses distributions, and contour plots. These artifacts may provide in AEC a twofold educational target: (i) for users, to provide visual understanding in real time of typical problems that must be understood in classic lectures of structural engineering; (ii) for developers, to provide meaningful applications of applied digital fabrication using sensors, microcontrollers, and GUI's and their potential in the development of tools related to Structural Health Monitoring (SHM) and the Internet of Things (IoT) among students of the AEC sector.
Expansion of adipose tissue‐derived stromal cells at “physiologic” hypoxia attenuates replicative senescence
Authors: Ratushnyy Andrey , Lobanova Margarita , Buravkova Ludmila B.
Published: June 2017

Multipotent mesenchymal stromal cells are considered as a perspective tool in cell therapy and regenerative medicine. Unfortunately, autologous cell therapy does not always provide positive outcomes in elder donors, perhaps as a result of the alterations of stem cell compartments. The mechanisms of stem and progenitor cell senescence and the factors engaged are investigated intensively. In present paper, we elucidated the effects of tissue‐related O2 on morphology, functions, and transcriptomic profile of adipose tissue‐derived stromal cells (ASCs) in replicative senescence in vitro model. Replicatively senescent ASCs at ambient (20%) O2 (12‐21 passages) demonstrated an increased average cell size, granularity, reactive oxygen species level, including anion superoxide, lysosomal compartment activity, and IL‐6 production. Decreased ASC viability and proliferation, as well as the change of more than 10 senescence‐associated gene expression were detected (IGF1, CDKN1C, ID1, CCND1, etc). Long‐term ASC expansion at low O2 (5%) revoked in part the replicative senescence‐associated alterations.
Inappropriate shock in a subcutaneous cardiac defibrillator due to residual air
Authors: Lee Shawn , Souvaliotis Nektarios , Mehta Davendra , Suri Ranjit
Published: June 2017

Key Clinical Message

Inappropriate shock due to residual air in subcutaneous implantable cardiac defibrillators is not a well‐known complication. Obtaining overpenetrated X‐rays, recognizing electrocardiogram findings, limiting blunt finger dissection, and switching to sense at another vector are techniques which might lead to avoidance of unnecessary wound exploration or device removal.
Kinetics of CO2 Adsorption/Desorption of Polyethyleneimine‐Mesoporous Silica
Authors: Al-Marri Mohammed J. , Kuti Yussuf O. , Khraisheh Majeda , Kumar Anand , Khader Mahmoud M.
Published: June 2017

The kinetics of adsorption of CO2 on solid sorbents based on polyethyleneimine/mesoporous silica (PEI/MPS) was studied by following the mass gain during CO2 flow. Linear (PEI‐423) and branched (PEI‐10k) polymers were studied. The solid sorbents were synthesized by impregnating the PEI into MPS foam. The kinetics of adsorption was fitted with a double‐exponential model. In contrast, the desorption process obeyed first‐order kinetics. The activation energy of desorption of PEI‐423 was lower than that of PEI‐10k, presumably because the branched polymer required more energy to expose its nitrogen to CO2. To increase the CO2 sorption capacity, the MPS was treated with nonionic surfactant materials prior to impregnation with PEI. This also lowered the maximum sorption temperature and desorption activation energies.
Fluidic Manufacture of Star‐Shaped Gold Nanoparticles
Authors: Silvestri Alessandro , Lay Luigi , Psaro Rinaldo , Polito Laura , Evangelisti Claudio
Published: June 2017

Star‐shaped gold nanoparticles (StarAuNPs) are extremely attractive nanomaterials, characterized by localized surface plasmon resonance which could be potentially employed in a large number of applications. However, the lack of a reliable and reproducible synthetic protocols for the production of StarAuNPs is the major limitation to their spreading. For the first time, here we present a robust protocol to manufacture reproducible StarAuNPs by exploiting a fluidic approach. Star‐shaped AuNPs have been synthesized by means of a seed‐less protocol, employing ascorbic acid as reducing agent at room temperature. Moreover, the versatility of the bench‐top microfluidic protocol has been exploited to afford hydrophilic, hydrophobic and solid‐supported engineered StarAuNPs, by avoiding intermediate NP purifications.
Nonheme Iron‐Oxo‐Catalyzed Methane Formation from Methyl Thioethers: Scope, Mechanism, and Relevance for Natural Systems
Authors: Benzing Kathrin , Comba Peter , Martin Bodo , Pokrandt Bianca , Keppler Frank
Published: June 2017

A range of nonheme oxo‐iron(IV) model systems with tetra‐ or pentadentate ligands is shown to produce methane from methionine and other thioethers. This model reaction for the natural aerobic production of methane is shown to proceed via two sulfoxidation steps involving the oxo‐iron(IV) complexes, with a bifurcation in the second step that either produces the sulfone or leads to demethylation with similar probabilities. In the presence of O2, the resulting methyl radicals produce methanol and formate or, in an O2‐depleted environment, lead to formation of methane.
Competitive Energy and Electron Transfer in β‐Functionalized Free‐Base Porphyrin–Zinc Porphyrin Dimer Axially Coordinated to C60: Synthesis, Supramolecular Formation and Excited‐State Processes
Authors: Hu Yi , Thomas Michael B. , Jinadasa R. G. Waruna , Wang Hong , D'Souza Francis
Published: June 2017

Simultaneous occurrence of energy and electron transfer events involving different acceptor sites in a newly assembled supramolecular triad comprised of covalently linked free‐base porphyrin–zinc porphyrin dyad, H2P−ZnP axially coordinated to electron acceptor fullerene, has been successfully demonstrated. The dyad was connected through the β‐pyrrole positions of the porphyrin macrocycle instead of the traditionally usedmeso‐positions for better electronic communication. Interestingly, the β‐pyrrole functionalization modulated the optical properties to such an extent that it was possible to almost exclusively excite the zinc porphyrin entity in the supramolecular triad. The measured binding constant for the complex with 1:1 molecular stoichiometry was in the order of 104 m−1revealing moderately stable complex formation. An energy level diagram constructed using optical, electrochemical and computational results suggested that both the anticipated energy and electron events are thermodynamically feasible in the triad. Consequently, it was possible to demonstrate occurrence of excited state energy transfer to the covalently linked H2P, and electron transfer to the coordinated ImC60from studies involving steady‐state and time‐resolved emission, and femto‐ and nanosecond transient absorption studies. The estimated energy transfer was around 67 % in the dyad with a rate constant of 1.1×109 s−1. In the supramolecular triad, the charge separated state was rather long‐lived although it was difficult to arrive the exact lifetime of charge separated state from nanosecond transient spectral studies due to overlap of strong triplet excited signals of porphyrin in the monitoring wavelength window. Nevertheless, simultaneous occurrence of energy and electron transfer in the appropriately positioned energy and electron acceptor entities in a supramolecular triad was possible to demonstrate in the present study, a step forward to unraveling the complex photochemical events occurring in natural photosynthesis and its implications in building light energy harvesting devices.
Harnessing White‐Light Luminescence via Tunable Singlet‐and Triplet‐Derived Emissions Based on Gold(III) Complexes *
Authors: Bachmann Michael , Blacque Olivier , Venkatesan Koushik
Published: June 2017

White light emitting gold(III) complexes were synthesized by tuning the percentage of metal dπ contribution in the charge transfer. This was achieved through specific tailoring of the ligand scaffold, which led to increase in the HOMO π‐energy properties, resulting in a decrease of efficiency on the intersystem crossing (ISC). As a consequence, monomolecular based singlet‐ and triplet‐derived emission covering the entire visible spectrum with quantum yield up to 28 % and CIE‐1931 chromaticity coordinates of (0.29, 0.33) to (0.32, 0.40) could be obtained. Furthermore, two complexes displayed excitation‐dependent emission property due to hyper‐ISC allowing the regulation of the ratio between fluorescence versus phosphorescence intensity and accomplish precise tuning of white light emission.
Investigation of concentration‐dependent diffusion on frontal instabilities and mass transfer in homogeneous porous media
Authors: Yuan Qingwang , Zhou Xiang , Zeng Fanhua , Knorr Kelvin D. , Imran Muhammad
Published: June 2017

Mass transfer plays an important role in influencing the efficiency of miscible displacements in solvent‐based processes in enhanced oil recovery. The mass transfer rate because of the pure molecular diffusion is very slow. However, this process can be greatly enhanced by the appearance of frontal instabilities called viscous fingering mechanisms, which are beneficial for improving the mixing and mass transfer between the injected solvent and oil. Instead of a piston‐like displacement, the interface between solvent and oil is very convoluted with intricate finger‐like patterns of the less viscous solvent intruding into the highly viscous oil. This intrusion significantly increases the surface area of contact of the two fluids and leads to more efficient mass transfer and mixing. Experimental measurements on the diffusion coefficients of two miscible fluids indicate that, instead of a constant diffusion coefficient (CDC), a concentration‐dependent diffusion coefficient (CDDC) is more realistic. In the present study, a CDDC relation in which the diffusion coefficient is exponentially proportional to concentration is adopted. Its effect on the development of frontal instabilities is examined through highly accurate nonlinear numerical simulations. The differences between the CDDC case and the widely assumed CDC case are discussed. Furthermore, the enhancement of frontal instabilities on mass transfer when the CDDC is considered is investigated at various mobility ratios and Peclet numbers. The special characteristics for the CDDC case indicate its important role in miscible displacements. Eventually, the relation of breakthrough time to parameters is correlated to accurately predict the breakthrough time in any CDDC scenario.
Assembly of CdTe Quantum Dots and Photosystem II Multilayer Films with Enhanced Photocurrent
Authors: Cai Peng , Jia Yi , Feng Xiyun , Li Jiao , Li Junbai
Published: June 2017

Photosystem II (PSII) is a photoactive protein that can drive water oxidation under light irradiation. Recently, PSII has been broadly investigated with the high demand on the bioenergy. Here, we demonstrate a facile approach for the fabrication of a photoactive electrode by the integration of PSII with quantum dots (QDs)/polyelectrolyte multilayers. The assembled QDs and PSII film with a polyelectrolyte based substrate via layer‐by‐layer assembly can remain the photoactivity of the PSII and broaden the absorption spectrum of PSII to produce a high photocurrent yield. The co‐assembly exhibits an obviously enhanced photocurrent under UV light irradiation. The proposed strategy can be considered for the reference and usage of PSII toward the solar energy conversion.
Hydrogen Storage on Li Coated BC3 Honeycomb Sheet
Authors: Zhang Yafei , Cheng Xinlu
Published: June 2017

Using density functional theory, we investigated the hydrogen storage capacity of Li coated BC3 honeycomb sheet. Our result indicates 18 H2 molecules can be adsorbed on BC3Li6 complex with a storage gravimetric density of 9.68 wt% and the average adsorption energy reaches 0.206 eV/H2. This is desirable for absorbing and desorbing H2 molecules at near ambient conditions.
Repurposing of Human Kinase Inhibitors in Neglected Protozoan Diseases
Authors: Dichiara Maria , Marrazzo Agostino , Prezzavento Orazio , Collina Simona , Rescifina Antonio , Amata Emanuele
Published: June 2017

Human African trypanosomiasis (HAT), Chagas disease, and leishmaniasis belong to a group of infectious diseases known as neglected tropical diseases and are induced by infection with protozoan parasites named trypanosomatids. Drugs in current use have several limitations, and therefore new candidate drugs are required. The majority of current therapeutic trypanosomatid targets are enzymes or cell‐surface receptors. Among these, eukaryotic protein kinases are a major group of protein targets whose modulation may be beneficial for the treatment of neglected tropical protozoan diseases. This review summarizes the finding of new hit compounds for neglected tropical protozoan diseases, by repurposing known human kinase inhibitors on trypanosomatids. Kinase inhibitors are grouped by human kinase family and discussed according to the screening (target‐based or phenotypic) reported for these compounds on trypanosomatids. This collection aims to provide insight into repurposed human kinase inhibitors and their importance in the development of new chemical entities with potential beneficial effects on the diseases caused by trypanosomatids.
Structural States of RORγt: X‐ray Elucidation of Molecular Mechanisms and Binding Interactions for Natural and Synthetic Compounds
Authors: Kallen Joerg , Izaac Aude , Be Celine , Arista Luca , Orain David , Kaupmann Klemens , Guntermann Christine , Hoegenauer Klemens , Hintermann Samuel
Published: June 2017

The T‐cell‐specific retinoic acid receptor (RAR)‐related orphan receptor‐γ (RORγt) is a key transcription factor for the production of pro‐inflammatory Th17 cytokines, which are implicated in the pathogenesis of autoimmune diseases. Over the years, several structurally diverse RORγt inverse agonists have been reported, but combining high potency and good physicochemical properties has remained a challenging task. We recently reported a new series of inverse agonists based on an imidazopyridine core with good physicochemical properties and excellent selectivity. Herein we report eight new X‐ray crystal structures for different classes of natural and synthetic compounds, including examples selected from the patent literature. Analysis of their respective binding modes revealed insight into the molecular mechanisms that lead to agonism, antagonism, or inverse agonism. We report new molecular mechanisms for RORγt agonism and propose a separation of the inverse agonists into two classes: those that act via steric clash and those that act via other mechanisms (for the latter, co‐crystallization with a co‐activator peptide and helix 12 in the agonist position is still possible). For the non‐steric clash inverse agonists, we propose a new mechanism (“water trapping”) which can be combined with other mechanisms (e.g., close contacts with H479). In addition, we compare the interactions made for selected compounds in the “back pocket” near S404 and in the “sulfate pocket” near R364 and R367. Taken together, these new mechanistic insights should prove useful for the design and optimization of further RORγt modulators.
Beyond the Hammett Effect: Using Strain to Alter the Landscape of Electrochemical Potentials
Authors: Casselman Matthew D. , Elliott Corrine F. , Modekrutti Subrahmanyam , Zhang Peter L. , Parkin Sean R. , Risko Chad , Odom Susan A.
Published: June 2017

The substitution of sterically bulky groups at precise locations along the periphery of fused‐ring aromatic systems is demonstrated to increase electrochemical oxidation potentials by preventing relaxation events in the oxidized state. Phenothiazines, which undergo significant geometric relaxation upon oxidation, are used as fused‐ring models to showcase that electron‐donating methyl groups, which would generally be expected to lower oxidation potential, can lead to increased oxidation potentials when used as the steric drivers. Reduction events remain inaccessible through this molecular design route, a critical characteristic for electrochemical systems where high oxidation potentials are required and in which reductive decomposition must be prevented, as in high‐voltage lithium‐ion batteries. This study reveals a new avenue to alter the redox characteristics of fused‐ring systems that find wide use as electroactive elements across a number of developing technologies.
Ionic‐Liquid‐Assisted Microwave Synthesis of Solid Solutions of Sr1−xBaxSnO3 Perovskite for Photocatalytic Applications
Authors: Alammar Tarek , Slowing Igor I. , Anderegg Jim , Mudring Anja‐Verena
Published: June 2017

Nanocrystalline Sr1−xBaxSnO3 (x=0, 0.2, 0.4, 0.8, 1) perovskite photocatalysts were prepared by microwave synthesis in an ionic liquid (IL) and subsequent heat‐treatment. The influence of the Sr/Ba substitution on the structure, crystallization, morphology, and photocatalytic efficiency was investigated and the samples were fully characterized. On the basis of X‐ray diffraction results, as the Ba content in the SrSnO3 lattice increases, a symmetry increase was observed from the orthorhombic perovskite structure for SrSnO3 to the cubic BaSnO3 structure. The analysis of the sample morphology by SEM reveals that the Sr1−xBaxSnO3 samples favor the formation of nanorods (500 nm–5 μm in diameter and several micrometers long). The photophysical properties were examined by UV/Vis diffuse reflectance spectroscopy. The band gap decreases from 3.85 to 3.19 eV with increasing Ba2+ content. Furthermore, the photocatalytic properties were evaluated for the hydroxylation of terephthalic acid (TA). The order of the activities for TA hydroxylation was Sr0.8Ba0.2SnO3>SrSnO3>BaSnO3>Sr0.6Ba0.4SnO3>Sr0.2Ba0.8SnO3. The highest photocatalytic activity was observed for Sr0.8Ba0.2SnO3, and this can be attributed to the synergistic impacts of the modification of the crystal structure and morphology, the relatively large surface area associated with the small crystallite size, and the suitable band gap and band‐edge position.
A secure electric energy management in smart home
Authors: Mbarek Bacem , Meddeb Aref , Ben Jaballah Wafa , Mosbah Mohamed
Published: June 2017

We formulate and study an intelligent and secure house electricity system on the basis of the Internet of Things. The security of sensitive data collected and transmitted by sensor nodes installed in home appliances and household electrical devices is critical, since the transmitted data can be easily manipulated by different types of attacks. The confidentiality and integrity of household electrical devices information must be assured to insure appropriate and timely response. Providing a secure aggregation mechanism is thus very essential to protect the integrity and the privacy of data aggregation. In this paper, we propose a secure data aggregation scheme that exploits compressed sensing (CS) to reduce the communication overhead of collected electrical power measurement. Then, the data will be encrypted by each sensor node after the compressing phase, and a cryptography hash algorithm is used to ensure data integrity. Finally, we apply an aggregation function for data priorities and then send the data for diagnosis. Then, we will present simulation results for the evaluation of the proposed electric energy management system.
Cervical cancer screening in the era of HPV vaccination: A review of shifting paradigms in cytopathology
Authors: Barroeta Julieta E. , Adhikari‐Guragain Deepti , Grotkowski Carolyn E.
Published: June 2017

Significant changes in cervical cancer screening practice, guidelines, and prevention of cervical cancer have taken place in recent years including the raising of initial cervical cancer screening age, changes in frequency of cytology screening, and the adoption of high risk HPV and cytology co‐testing for some patients; the introduction of the bivalent, quadrivalent, and 9‐valent HPV vaccines; and the recent approval of high risk HPV testing as primary screening with the use of cytology as triage in positive cases. This review discusses the significance of primary HPV screening, the impact of HPV vaccination in the prevalence of cervical cancer and its precursors, the interplay between high risk HPV testing and vaccination, and the implications for clinical and cytological management. Future strategies for cervical screening in the post‐vaccination era are also discussed.
Cellular and molecular attributes of neural stem cell niches in adult zebrafish brain
Authors: Anand Surendra Kumar , Mondal Amal Chandra
Published: June 2017

Adult neurogenesis is a complex, presumably conserved phenomenon in vertebrates with a broad range of variations regarding neural progenitor/stem cell niches, cellular composition of these niches, migratory patterns of progenitors and so forth among different species. Current understanding of the reasons underlying the inter‐species differences in adult neurogenic potential, the identification and characterization of various neural progenitors, characterization of the permissive environment of neural stem cell niches and other important aspects of adult neurogenesis is insufficient. In the last decade, zebrafish has emerged as a very useful model for addressing these questions. In this review, we have discussed the present knowledge regarding the neural stem cell niches in adult zebrafish brain as well as their cellular and molecular attributes. We have also highlighted their similarities and differences with other vertebrate species. In the end, we shed light on some of the known intrinsic and extrinsic factors that are assumed to regulate the neurogenic process in adult zebrafish brain. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 1188–1205, 2017
Wnt and Shh signals regulate neural stem cell proliferation and differentiation in the optic tectum of adult zebrafish
Authors: Shitasako Shiori , Ito Yoko , Ito Ryoichi , Ueda Yuto , Shimizu Yuki , Ohshima Toshio
Published: June 2017

Adult neurogenesis occurs more commonly in teleosts, represented by zebrafish, than in mammals. Zebrafish is therefore considered a suitable model to study adult neurogenesis, for which the regulatory molecular mechanisms remain little known. Our previous study revealed that neuroepithelial‐like neural stem cells (NSCs) are located at the edge of the dorsomedial region. We also showed that Notch signaling inhibits NSC proliferation in this region. In the present study, we reported the expression of Wnt and Shh signaling components in this region of the optic tectum. Moreover, inhibitors of Wnt and Shh signaling suppressed NSC proliferation, suggesting that these pathways promote NSC proliferation. Shh is particularly required for maintaining Sox2‐positive NSCs. Our experimental data also indicate the involvement of these signaling pathways in neural differentiation from NSCs. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 1206–1220, 2017
Applying community ecological theory to maximize productivity of cultivated biocrusts
Authors: Bowker Matthew A. , Antoninka Anita J. , Durham Rebecca A.
Published: June 2017

Degraded rangelands around the world may benefit from the reestablishment of lost biological soil crusts (biocrusts, soil surface cryptogamic‐microbial communities). Cultivation of biocrust organisms is the first step in this process, and may benefit from harnessing species interactions. Species interactions are a dominant force structuring ecological communities. One key element of community structure, species richness, is itself important because it can promote the productivity of the entire community. Here, we use biological soil crusts as a model to test the effects of species interactions on production of biocrust materials for use in ecosystem rehabilitation. We screened eight different moss and lichen species from semiarid rangelands of Montana, USA, for growth potential under two watering regimes. Mosses generally grew well, but we were unable to cultivate the selected lichen species. We produced a >400% increase in the biomass of one species (Ceratodon purpureus). We tested whether a parasite–host relationship between two lichens could be used to enhance productivity of the parasite species, but this also resulted in no net gain of lichen productivity. Finally, we constructed all possible community combinations from a pool of five moss species to test for overyielding (community productivity exceeding that expected from the growth of community members in monoculture), and to determine both if, and the mode in which, species richness increases productivity. Polycultures yielded more than would be expected based upon the production of community constituents in monoculture. Using structural equation models, we determined that there was a modest effect of species richness on community productivity (r = 0.24–0.25), which was independent of a stronger effect of the identity of species in the community (r = 0.41–0.50). These results will contribute to the optimization of biocrust cultivation, promoting the development of this emerging ecological rehabilitation technology.
Dispersal corridors for plant species in the Poyang Lake Basin of southeast China identified by integration of phylogeographic and geospatial data
Authors: Fan Dengmei , Sun Zhixia , Li Bo , Kou Yixuan , Hodel Richard G. J. , Jin Zhinong , Zhang Zhiyong
Published: June 2017

Measuring the dispersal of wildlife through landscapes is notoriously difficult. Recently, the categorical least cost path algorithm that integrates population genetic data with species distribution models has been applied to reveal population connectivity. In this study, we use this method to identify the possible dispersal corridors of five plant species (Castanopsis tibetana, Schima superba, Cyclocarya paliurus, Sargentodoxa cuneata, Eomecon chionantha) in the Poyang Lake Basin (PLB, largely coinciding with Jiangxi Province), China, in the late Quaternary. The results showed that the strongest population connectivity for the five species occurred in the Wuyi Mountains and the Yu Mountains of the eastern PLB (East Corridor) during the late Quaternary. In the western PLB, populations of the five species were connected by the Luoxiao Mountains and the Jiuling Mountains (West Corridor) but with a lower degree of connectivity. There were some minor connections between the eastern and the western populations across the Gannan Hills. When the corridors of five species were overlaid, the East Corridor and the West Corridor were mostly shared by multiple species. These results indicate that plant species in the PLB could have responded to the Quaternary climate changes by moving along the East Corridor and the West Corridor. Given that dispersal corridors have seldom been considered in the governmental strategies of biodiversity conservation in the PLB, preserving and restoring natural vegetation along these corridors should be prioritized to mitigate the effects of anthropogenic climate change by facilitating migration of plant species and other biota.
Patient‐reported outcomes in the SOluble guanylate Cyclase stimulatoR in heArT failurE patientS with PRESERVED ejection fraction (SOCRATES‐PRESERVED) study
Authors: Filippatos Gerasimos , Maggioni Aldo P. , Lam Carolyn S.P. , Pieske‐Kraigher Elisabeth , Butler Javed , Spertus John , Ponikowski Piotr , Shah Sanjiv J. , Solomon Scott D. , Scalise Andrea‐Viviana , Mueller Katharina , Roessig Lothar , Bamber Luke , Gheorghiade Mihai , Pieske Burkert
Published: June 2017

Aims

Exploratory assessment of the potential benefits of the novel soluble guanylate cyclase stimulator vericiguat on health status in patients with heart failure (HF) with preserved ejection fraction.

Methods and results

The SOCRATES‐PRESERVED trial randomized patients with chronic HF and ejection fraction ≥ 45% within 4 weeks of decompensation to 12 weeks of treatment with titrated doses of vericiguat (1.25, 2.5, 5, and 10 mg once daily) or placebo. Health status was assessed with the disease‐specific Kansas City Cardiomyopathy Questionnaire (KCCQ) and the generic health‐related quality of life measure EQ‐5D. In total, 477 patients were randomized 12.9 ± 9.0 days after hospitalization or if requiring outpatient treatment with intravenous diuretics for HF. Baseline KCCQ clinical summary score (CSS), a combination of symptom and physical function domains, was 52.3 ± 20.4 in the 10 mg arm and 54.1 ± 23.0 in placebo, and EQ‐5D US index score was 0.74 ± 0.2 and 0.73 ± 0.2, respectively. A larger proportion of patients treated with vericiguat in the 10 mg arm, compared with placebo, achieved clinically meaningful improvements in KCCQ‐CSS (82.0% vs. 59.0%, number needed to treat = 4.35, P = 0.0052). Important domains of the KCCQ as well as EQ‐5D scores demonstrated a dose‐dependent relationship with vericiguat. In the 10 mg arm, the mean physical limitations domain increased by +17.2 ± 19.1 at 12 weeks, compared with +4.5 ± 21.6 in placebo (P = 0.0009). The EQ‐5D US index score increased by +0.064 ± 0.167 in the 10 mg arm, compared with a decrease of −0.009 ± 0.195 in placebo (P = 0.0461). Improvements in KCCQ and EQ‐5D scores paralleled physician‐assessed NYHA class and clinical congestion.

Conclusion

Vericiguat, in exploratory hypothesis‐generating analyses, was associated with clinically important improvements in patients' health status, as assessed by the KCCQ and EQ‐5D. Further studies should be conducted to test the hypothesis that vericiguat improves physical functioning and health‐related quality of life in patients with HF with preserved ejection fraction.
Ag[B(SO4)2] – Synthesis, Crystal Structure, and Characterization of the First Precious‐Metal Borosulfate
Authors: Bruns Jörn , Podewitz Maren , Schauperl Michael , Liedl Klaus R. , Janka Oliver , Pöttgen Rainer , Huppertz Hubert
Published: June 2017

The reaction of Ag(NO3) with H3BO3 in oleum (20 % SO3) yielded single crystals of Ag[B(SO4)2] [tetragonal, P4/ncc, Z = 4, a = 8.6679(5) Å, c = 7.2897(5) Å, V = 547.69(7) Å3]. In Ag[B(SO4)2], infinite anionic chains, according to the Niggli formula ∞1[B(SO4)4/2]–, are found in tetragonal‐rod packing with charge compensation by AgI cations. The chains are built by central boron atoms coordinated through oxygen atoms to four bidentate bridging SO4 tetrahedra. Terminal oxygen atoms of the SO4 tetrahedra coordinate to the silver cations in the form of slightly distorted square prisms. Magnetochemical investigations reveal the expected closed‐shell behavior of d10 cations. DFT investigations of the solid‐state structure corroborate the experimental findings and permit the assignment of vibrational spectroscopic data.
Bis(4‐methylbenzoxazol‐2‐yl)methanide in s‐Block Metal Coordination
Authors: Koehne Ingo , Herbst‐Irmer Regine , Stalke Dietmar
Published: June 2017

On the basis of the bis(4‐methylbenzoxazol‐2‐yl)methanide ligand three new alkali or alkaline earth metal compounds were synthesized, and their solid‐state structures are discussed in detail. On the way to new alkaline earth metal species a promising potassium precursor complex [K{(4‐MeNCOC6H3)2CH}{η5‐K(4‐MeNCOC6H3)2CH}(THF)]∞ (2) and a homoleptic magnesium [Mg{(4‐MeNCOC6H3)2CH}2] (3) and calcium complex [Ca{(4‐MeNCOC6H3)2CH}2(THF)2]·THF (4) were obtained.
Highly Selective Chromium(0)‐Mediated Insertion of Nitriles into a Nonpolar P–P Bond of a Substituted Hexahydro‐1,4‐diaza‐2,3,5,6‐tetraphosphorine
Authors: Höhne Martha , Müller Bernd H. , Peulecke Normen , Spannenberg Anke , Jiao Haijun , Rosenthal Uwe
Published: June 2017

The cleavage of P–P σ bonds has long been a subject of interest and is investigated widely. P–P bonds can be cleaved homolytically to yield phosphinyl radicals, which can be persistent and stable for long periods or undergo further reactions. P–P bonds that exhibit polarization owing to different substitution can be opened heterolytically. Furthermore, it is possible to activate them through metal interactions. Both processes can be followed by the insertion of unsaturated small molecules into the homonuclear σ bonds. Herein, we present the versatile coordination behavior of a hexahydro‐1,4‐diaza‐2,3,5,6‐tetraphosphorine derivative to chromium carbonyls. Amongst other reactions, we observed a highly selective metal‐mediated insertion of a nitrile into an originally symmetrical P–P σ bond.
Uniform Discrete Nitrogen‐Doped Double‐Shelled Cage‐like Hollow Carbon Spheres with Direct Large Mesopores for High‐Performance Supercapacitors
Authors: Fang Mingming , Chen Zhimin , Liu Yuan , Liu Wei , Xu Qun
Published: June 2017

Uniform discrete nitrogen‐doped double‐shelled cage‐like hollow carbon spheres (DCHCSs) with direct large mesopores on both shells were successfully synthesized for the first time by using cross‐linked polystyrene spheres and silica particles as a dual template and dopamine as the source of both carbon and nitrogen. These DCHCSs exhibited high specific capacitance values of 229.3 and 160 F g−1 at 1 and 10 A g−1, respectively, with excellent rate capability and cycling stability.
Experimental evolution reveals that sperm competition intensity selects for longer, more costly sperm
Authors: Godwin Joanne L. , Vasudeva Ramakrishnan , Michalczyk Łukasz , Martin Oliver Y. , Lumley Alyson J. , Chapman Tracey , Gage Matthew J. G.
Published: June 2017

It is the differences between sperm and eggs that fundamentally underpin the differences between the sexes within reproduction. For males, it is theorized that widespread sperm competition leads to selection for investment in sperm numbers, achieved by minimizing sperm size within limited resources for spermatogenesis in the testis. Here, we empirically examine how sperm competition shapes sperm size, after more than 77 generations of experimental selection of replicate lines under either high or low sperm competition intensities in the promiscuous flour beetle Tribolium castaneum. After this experimental evolution, populations had diverged significantly in their sperm competitiveness, with sperm in ejaculates from males evolving under high sperm competition intensities gaining 20% greater paternity than sperm in ejaculates from males that had evolved under low sperm competition intensity. Males did not change their relative investment into sperm production following this experimental evolution, showing no difference in testis sizes between high and low intensity regimes. However, the more competitive males from high sperm competition intensity regimes had evolved significantly longer sperm and, across six independently selected lines, there was a significant association between the degree of divergence in sperm length and average sperm competitiveness. To determine whether such sperm elongation is costly, we used dietary restriction experiments, and revealed that protein-restricted males produced significantly shorter sperm. Our findings therefore demonstrate that sperm competition intensity can exert positive directional selection on sperm size, despite this being a costly reproductive trait.
Evacuation response behaviour in unannounced evacuation of licensed premises
Authors: Boyce Karen , McConnell Nigel , Shields Jim
Published: June 2017

An understanding of the behaviour of individuals and groups during evacuation is key to the development of evacuation scenarios as part of an engineering design solution. Furthermore, it is important that engineers have reliable and accurate data on pre‐evacuation times and movement for use in time‐based evacuation analysis. This paper presents, for the first time in the published literature, a detailed analysis of an unannounced evacuation of licensed premises and provides important data and understanding regarding behaviour for use in fire safety engineering design and evacuation modelling. Findings on recognition times, response behaviours, pre‐evacuation times and final exit flows for a function room and lounge bar in the licensed property are provided. The results suggest that the evacuation time in the lounge bar was characterised by generally longer pre‐evacuation times and relatively shorter movement times, whereas the evacuation time in the more densely populated function room was characterised by shorter pre‐evacuation times but extended flow times. The paper highlights important design and management issues with respect to the evacuation of persons under the influence of alcohol and considers the impact of staff intervention through directed voice communications. The variation in response behaviours between the two separate areas of the premises are highlighted and discussed. Copyright © 2017 John Wiley & Sons, Ltd.
Efficiency performance of China's health care delivery system
Authors: Zhang Luyu , Cheng Gang , Song Suhang , Yuan Beibei , Zhu Weiming , He Li , Ma Xiaochen , Meng Qingyue
Published: June 2017

Improving efficiency performance of the health care delivery system has been on the agenda for the health system reform that China initiated in 2009. This study examines the changes in efficiency performance and determinants of efficiency after the reform to provide evidence to assess the progress of the reform from the perspective of efficiency. Descriptive analysis, Data Envelopment Analysis, the Malmquist Index, and multilevel regressions are used with data from multiple sources, including the World Bank, the China Health Statistical Yearbook, and routine reports. The results indicate that over the last decade, health outcomes compared with health investment were relatively higher in China than in most other countries worldwide, and the trend was stable. The overall efficiency and total factor productivity increased after the reform, indicating that the reform was likely to have had a positive impact on the efficiency performance of the health care delivery system. However, the health care delivery structure showed low system efficiency, mainly attributed to the weakened primary health care system. Strengthening the primary health care system is central to enhancing the future performance of China's health care delivery system.
A pilot study of community‐based self‐sampling for HPV testing among non‐attenders of cervical cancer screening programs in El Salvador
Authors: Laskow Bari , Figueroa Ruben , Alfaro Karla M. , Scarinci Isabel C. , Conlisk Elizabeth , Maza Mauricio , Chang Judy C. , Cremer Miriam
Published: June 2017

Objective

To establish the feasibility and acceptability of home‐based HPV self‐sampling among women who did not attend screening appointments in rural El Salvador.

Methods

In a cross‐sectional study, data were collected from May 2015 to January 2016 among 60 women aged 30–59 years who were not pregnant, provided informed consent, had not been screened in 2 years, had no history of pre‐cancer treatment, and did not attend a scheduled HPV screening. Participants completed questionnaires and received educational information before being given an opportunity to self‐sample with the Hybrid Capture 2 High Risk HPV DNA Test.

Results

Self‐sampling was accepted by 41 (68%) participants. Almost all women chose to self‐sample because the process was easy (40/41, 98%), could be performed at home (40/41, 98%), and saved time (38/41, 93%), and because they felt less embarrassed (33/41, 80%). The most common reason for declining the test was not wanting to be screened (8/19, 42%). The prevalence of high‐risk HPV types among women who accepted self‐sampling was 17% (7/41).

Conclusion

For most women, community‐based self‐sampling was an acceptable way to participate in a cervical cancer screening program. In low‐resource countries, incorporating community‐based self‐sampling into screening programs might improve coverage of high‐risk women.