bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the innermost dust formation region of the oxygen-rich AGB star IK Tauri with VLT/SPHERE-ZIMPOL and VLTI/AMBER
Authors: Adam C. , Ohnaka K.
Published: July 2019

Context. Low- and intermediate-mass stars on the asymptotic giant branch (AGB) are known to be prevalent dust providers to galaxies, replenishing the surrounding medium with molecules and dust grains. However, the mechanisms responsible for the formation and acceleration of dust in the cool extended atmospheres of AGB stars are still open to debate.

Aims. We present visible polarimetric imaging observations of the oxygen-rich AGB star IK Tau obtained with the high-resolution polarimetric imager VLT/SPHERE-ZIMPOL at post-maximum light (phase 0.27) as well as high-spectral resolution long-baseline interferometric observations with the AMBER instrument at the Very Large Telescope Interferometer (VLTI). We aim to spatially resolve the dust and molecule formation regions, and to investigate their physical and chemical properties within a few stellar radii of IK Tau.

Methods. IK Tau was observed with VLT/SPHERE-ZIMPOL at three wavelengths in the pseudo-continuum (645, 748, and 820 nm), in the Hα line at 656.3 nm, and in the TiO band at 717 nm. The VLTI/AMBER observations were carried out in the wavelength region of the CO first overtone lines near 2.3 μm with a spectral resolution of 12 000.

Results. The excellent polarimetric imaging capabilities of SPHERE-ZIMPOL have allowed us to spatially resolve clumpy dust clouds at 20–50 mas from the central star, which corresponds to 2–5 R⋆ when combined with a central star’s angular diameter of 20.7 ± 1.53 mas measured with VLTI/AMBER. The diffuse, asymmetric dust emission extends out to ~73 R⋆. We find that the TiO emission extends to 150 mas (15 R⋆). The AMBER data in the individual CO lines also suggest a molecular outer atmosphere extending to ~1.5 R⋆. The results of our 2D Monte Carlo radiative transfer modelling of dust clumps suggest that the polarized intensity and degree of linear polarization can be reasonably explained by small-sized (0.1 μm) grains of Al2O3, MgSiO3, or Mg2SiO4 in an optically thin shell (τ550 nm = 0.5 ± 0.1) with an inner and outer boundary radius of 3.5 R⋆ and ≳25 R⋆, respectively. The observed clumpy structures can be reproduced by a density enhancement of a factor of 3.0 ± 0.5. However, the model still predicts the total intensity profiles to be too narrow compared to the observed data, which may be due to the TiO emission and/or grains other than homogeneous, filled spheres.

Conclusions. IK Tau’s mass-loss rate is 20–50 times higher than the previously studied AGB stars W Hya, R Dor, and o Cet. Nevertheless, our observations of IK Tau revealed that clumpy dust formation occurs close to the star as seen in those low mass-rate AGB stars.
Downregulation of RPS15A by miR-29a-3p attenuates cell proliferation in colorectal carcinoma
Authors: Zheng Zilei , Cui Haitao , Wang Yi , Yao Weilong
Published: July 2019

miR-29a-3p has been reported to function as a tumor suppressor in several cancers. However, the biological function role of miR-29a-3p in colorectal carcinoma (CRC) has not been well investigated. In this study, we found that miR-29a-3p was at lower level expression in CRC tissues and cell lines. Experimental up-regulation miR-29a-3p with mimic could inhibit cell proliferation, but induced cell cycle arrest at G0/G1 phase and apoptosis in CRC cells. MiR-29a-3p overexpression significantly down-regulated the expression levels of CDK4, Cyclin D1, and Bax, but up-regulated the expression levels of p21 and Bcl-2 in DLD-1 cells. Moreover, ribosomal protein S15A (RPS15A) was predicted and confirmed as a direct target gene of miR-29a-3p. Furthermore, restoration of RPS15A could rescue the phenotypic changes caused by miR-29a-3p. The findings demonstrate miR-29a-3p inhibits CRC cell function possibly by targeting RPS15A, which might be exploited therapeutically in CRC.
Cloning and identification of the Frigocyclinone biosynthetic gene cluster from Streptomyces griseus strain NTK 97
Authors: Mo Jian , Ye Jiang , Chen Haozhe , Hou Bingbing , Wu Haizhen , Zhang Huizhan
Published: July 2019

Frigocyclinone is a novel antibiotic with antibacterial and anticancer activities. It is produced by both Antarctica-derived Streptomyces griseus NTK 97 and marine sponge-associated Streptomyces sp. M7_15. Here, we first report the biosynthetic gene cluster of frigocyclinone in the S. griseus NTK 97. The frigocyclinone gene cluster spans a DNA region of 33-kb which consists of 30 open reading frames (ORFs), encoding minimal type II polyketide synthase, aromatase and cyclase, redox tailoring enzymes, sugar biosynthesis-related enzymes, C-glycosyltransferase, a resistance protein, and three regulatory proteins. Based on the bioinformatic analysis, a biosynthetic pathway for frigocyclinone was proposed. Second, to verify the cloned gene cluster, CRISPR-Cpf1 mediated gene disruption was conducted. Mutant with the disruption of beta-ketoacyl synthase encoding gene frig20 fully loses the ability of producing frigocyclinone, while inactivating the glycosyltransferase gene frig1 leads to the production of key intermediate of anti-MRSA anthraquinone tetrangomycin.
Computing the self-consistent field in Kohn–Sham density functional theory
Authors: Woods N D , Payne M C , Hasnip P J
Published: July 2019

A new framework is presented for evaluating the performance of self-consistent field methods in Kohn–Sham density functional theory (DFT). The aims of this work are two-fold. First, we explore the properties of Kohn–Sham DFT as it pertains to the convergence of self-consistent field iterations. Sources of inefficiencies and instabilities are identified, and methods to mitigate these difficulties are discussed. Second, we introduce a framework to assess the relative utility of algorithms in the present context, comprising a representative benchmark suite of over fifty Kohn–Sham simulation inputs, the scf-x

n
suite. This provides a new tool to develop, evaluate and compare new algorithms in a fair, well-defined and transparent manner.
Determining dose enhancement factors of high-Z nanoparticles from simulations where lateral secondary particle disequilibrium exists
Authors: Rabus Hans , Gargioni Elisabetta , Li Wei Bo , Nettelbeck Heidi , Villagrasa Carmen
Published: July 2019

Nanoparticles (NPs) containing high atomic number (high-Z) materials have been shown to enhance the radiobiological effectiveness of ionizing radiation. This effect is often attributed to an enhancement of the absorbed dose in the vicinity of the NPs, based on Monte Carlo simulations that show a significant local enhancement of the energy deposition on the microscopic scale. The results of such simulations may be significantly biased and lead to a severe overestimation of the dose enhancement if the condition of secondary particle equilibrium is not met in the simulation setup. This current work shows an approach to estimate a ‘realistic’ dose enhancement from the results of such biased simulations which is based on published photon interaction data and provides a way for correcting biased results.
Mott polaritons in cavity-coupled quantum materials
Authors: Kiffner Martin , Coulthard Jonathan , Schlawin Frank , Ardavan Arzhang , Jaksch Dieter
Published: July 2019

We show that strong electron–electron interactions in quantum materials can give rise to electronic transitions that couple strongly to cavity fields, and collective enhancement of these interactions can result in ultrastrong effective coupling strengths. As a paradigmatic example we consider a Fermi–Hubbard model coupled to a single-mode cavity and find that resonant electron-cavity interactions result in the formation of a quasi-continuum of polariton branches. The vacuum Rabi splitting of the two outermost branches is collectively enhanced and scales with

g

eff

∝

2
L

, where L is the number of electronic sites, and the maximal achievable value for g
eff is determined by the volume of the unit cell of the crystal. We find that g
eff for existing quantum materials can by far exceed the width of the first excited Hubbard band. This effect can be experimentally observed via measurements of the optical conductivity and does not require ultrastrong coupling on the single-electron level. Quantum correlations in the electronic ground state as well as the microscopic nature of the light–matter interaction enhance the collective light–matter interaction compared to an ensemble of independent two-level atoms interacting with a cavity mode.
Fabrication and characterization of optical nanofiber interferometer and resonator for the visible range
Authors: Ding Chengjie , Loo Vivien , Pigeon Simon , Gautier Romain , Joos Maxime , Wu E , Giacobino Elisabeth , Bramati Alberto , Glorieux Quentin
Published: July 2019

We report the fabrication and characterization of photonic structures using tapered optical nanofibers. Thanks to the extension of the evanescent electromagnetic field outside of the nanofiber two types of devices can be built: a ring interferometer and a knot resonator. We propose a general approach to predict the properties of these structures using the linear coupling theory. In addition, we describe a new source of birefringence due to the ovalization of a nanofiber under strong bending, known in mechanical engineering as the Brazier effect.
Subradiance-protected excitation transport
Authors: Needham Jemma A , Lesanovsky Igor , Olmos Beatriz
Published: July 2019

We explore excitation transport within a one-dimensional chain of atoms where the atomic transition dipoles are coupled to the free radiation field. When the atoms are separated by distances smaller or comparable to the wavelength of the transition, the exchange of virtual photons leads to the transport of the excitation through the lattice. Even though this is a strongly dissipative system, we find that the transport is subradiant, that is, the excitation lifetime is orders of magnitude longer than the one of an individual atom. In particular, we show that a subspace of the spectrum is formed by subradiant states with a linear dispersion relation, which allows for the dispersionless transport of wave packets over long distances with virtually zero decay rate. Moreover, the group velocity and direction of the transport can be controlled via an external uniform magnetic field while preserving its subradiant character. The simplicity and versatility of this system, together with the robustness of subradiance against disorder, makes it relevant for a range of applications such as lossless energy transport and long-time light storage.
Machine learning by unitary tensor network of hierarchical tree structure
Authors: Liu Ding , Ran Shi-Ju , Wittek Peter , Peng Cheng , García Raul Blázquez , Su Gang , Lewenstein Maciej
Published: July 2019

The resemblance between the methods used in quantum-many body physics and in machine learning has drawn considerable attention. In particular, tensor networks (TNs) and deep learning architectures bear striking similarities to the extent that TNs can be used for machine learning. Previous results used one-dimensional TNs in image recognition, showing limited scalability and flexibilities. In this work, we train two-dimensional hierarchical TNs to solve image recognition problems, using a training algorithm derived from the multi-scale entanglement renormalization ansatz. This approach introduces mathematical connections among quantum many-body physics, quantum information theory, and machine learning. While keeping the TN unitary in the training phase, TN states are defined, which encode classes of images into quantum many-body states. We study the quantum features of the TN states, including quantum entanglement and fidelity. We find these quantities could be properties that characterize the image classes, as well as the machine learning tasks.
Trends and controls of terrestrial gross primary productivity of China during 2000–2016
Authors: Ma Jun , Xiao Xiangming , Miao Renhui , Li Yao , Chen Bangqian , Zhang Yao , Zhao Bin
Published: July 2019

Terrestrial gross primary productivity (GPP) is an important flux that drives the global carbon cycle. However, quantifying the trend and the control factor of GPP from the pixel level to the regional level is still a challenge. We generated monthly GPP dataset using the vegetation photosynthesis model and calculated the interannual linear trend for China during 2000–2016. The Breaks For Additive Seasonal and Trend method was applied to detect the timing of breakpoint and trends shift of monthly GPP, while boosted regression tree analysis was used to identify the most important factor and its relative influence on GPP based on gridded leaf area index (LAI), aerosol optical thickness, and NCEP-DOE Reanalysis II meteorological data. The results show that annual mean GPP was significantly (P < 0.001, R
2 = 0.78) increased, especially in the Loess Plateau and South China, from 2000 to 2016. The change rate of annual mean GPP declined from 18.82 g C m−2 yr−1 in 2000–2008 to 3.48 g C m−2 yr−1 in 2008–2016. About 55.4% of the breakpoints occur between 2009 and 2011 and was mainly distributed in Qinghai-Tibet Plateau, Central China, Southwestern China, and South China, and negative oriented GPP trends variation type still accounts for about 28.76%. LAI and temperature related factors generally had the highest relative influence on GPP in the north part and south part of China, respectively. Our study indicates that the ecological restoration projects and rapid urbanization have respectively induced the most obvious increase and decrease trends of GPP in China. Land cover change and climate change are the main reasons for GPP dynamics in the north and south part of China, respectively.
High harmonic generation with Laguerre–Gaussian beams
Authors: Paufler Willi , Böning Birger , Fritzsche Stephan
Published: July 2019

We summarize the development of high harmonic generation (HHG) with linearly polarized Laguerre–Gaussian (LG) beams and their superpositions to explain the non-perturbative aspects of HHG. Furthermore, we show that circularly polarized extreme ultraviolet vortices with well-defined orbital angular momentum (OAM) can be generated by HHG with bicircular LG beams. We introduce photon diagrams in order to explain how to calculate the OAM and the polarization of the generated harmonics by means of simultaneous conservation of spin angular momentum and OAM. Moreover, we show how the intensity ratio of the driving fields in HHG with bicircular LG beams further enhances the generation of circularly polarized twisted attosecond pulse trains.
Fabry–Perot type resonant modes of exciton luminescence in Cu2O nanowires
Authors: Wang Peng , Liu Guipeng , Zhao Xinhong , Li Hairong , Li Lingshan , Lian Junbo , Gao Xiaohu , Huang Zeyu
Published: July 2019

Single Cu2O nanowires (NWs) were fabricated by the two-step method we reported previously (Wang et al 2014 RSC Advances
4 37542). Band-edge exciton photoluminescence (PL) was observed from individual NWs at room temperature using excitation at 325 nm. The PL signals were assigned to Fabry–Perot (F-P) type standing waves in a right cylindrical dielectric cavity (resonator) for a representative range of different wire lengths and diameters. We found that the mode spacing of F-P resonances varied inversely as the NW length as expected. For the region of NW diameters from 140 to 200 nm, and NW length between 2–5 mm, E-field simulations by COMSOL Multiphysics finite element analysis indicate that the main F-P mode propagating inside the NW is the HE11 mode. When the diameter exceeds 200 nm, there are at least two F-P type modes supported in the NWs. Our results further the understanding of exciton photoluminescence in Cu2O NWs and demonstrates the existence of enhanced mode frequencies based on the geometry of the optical micro-cavity. We further identify potential applications in exciton-driven optoelectronic devices and light emission enhanced by optical micro-cavities.
Reconsidering Domesticity through the Lens of Empire and Settler Society in North America
Authors: Sklar Kathryn Kish
Published: July 2019

Our reconsideration of domesticity comes at a time when empire and colonial and postcolonial categories of analysis are informing many fields of historical study. This essay traces the historiographic origins of the intersection of domesticity and empire, focusing on domesticity’s usefulness as a window on cross-cultural intimacy and conflict. It also offers an example of how previous treatments of domesticity might be revised by taking empire and settler society into account.
Identifying emerging phenomenon in long temporal phenotyping experiments
Authors: Peng Jiajie , Lu Junya , Hoh Donghee , Dina Ayesha S , Shang Xuequn , Kramer David M , Chen Jin
Published: July 2019

Motivation

The rapid improvement of phenotyping capability, accuracy and throughput have greatly increased the volume and diversity of phenomics data. A remaining challenge is an efficient way to identify phenotypic patterns to improve our understanding of the quantitative variation of complex phenotypes, and to attribute gene functions. To address this challenge, we developed a new algorithm to identify emerging phenomena from large-scale temporal plant phenotyping experiments. An emerging phenomenon is defined as a group of genotypes who exhibit a coherent phenotype pattern during a relatively short time. Emerging phenomena are highly transient and diverse, and are dependent in complex ways on both environmental conditions and development. Identifying emerging phenomena may help biologists to examine potential relationships among phenotypes and genotypes in a genetically diverse population and to associate such relationships with the change of environments or development.

Results

We present an emerging phenomenon identification tool called Temporal Emerging Phenomenon Finder (TEP-Finder). Using large-scale longitudinal phenomics data as input, TEP-Finder first encodes the complicated phenotypic patterns into a dynamic phenotype network. Then, emerging phenomena in different temporal scales are identified from dynamic phenotype network using a maximal clique based approach. Meanwhile, a directed acyclic network of emerging phenomena is composed to model the relationships among the emerging phenomena. The experiment that compares TEP-Finder with two state-of-art algorithms shows that the emerging phenomena identified by TEP-Finder are more functionally specific, robust and biologically significant.

Availability and implementation

The source code, manual and sample data of TEP-Finder are all available at: http://phenomics.uky.edu/TEP-Finder/.

Supplementary information

Supplementary data are available at Bioinformatics online.
VariantQC: a visual quality control report for variant evaluation
Authors: Yan Melissa Y , Ferguson Betsy , Bimber Benjamin N
Published: July 2019

Large scale genomic studies produce millions of sequence variants, generating datasets far too massive for manual inspection. To ensure variant and genotype data are consistent and accurate, it is necessary to evaluate variants prior to downstream analysis using quality control (QC) reports. Variant call format (VCF) files are the standard format for representing variant data; however, generating summary statistics from these files is not always straightforward. While tools to summarize variant data exist, they generally produce simple text file tables, which still require additional processing and interpretation. VariantQC fills this gap as a user friendly, interactive visual QC report that generates and concisely summarizes statistics from VCF files. The report aggregates and summarizes variants by dataset, chromosome, sample and filter type. The VariantQC report is useful for high-level dataset summary, quality control and helps flag outliers. Furthermore, VariantQC operates on VCF files, so it can be easily integrated into many existing variant pipelines.

Availability and implementation

DISCVRSeq's VariantQC tool is freely available as a Java program, with the compiled JAR and source code available from https://github.com/BimberLab/DISCVRSeq/. Documentation and example reports are available at https://bimberlab.github.io/DISCVRSeq/.
Advances in the phylogeny of the South American cool-season grass genus Chascolytrum (Poaceae, Pooideae): a new infrageneric classification
Authors: Da Silva Leonardo Nogueira , Essi Liliana , Iganci João Ricardo Vieira , Souza-Chies Tatiana Teixeira De
Published: July 2019

Chascolytrum, as currently circumscribed, includes 22–23 South American species that were previously included in nine different genera (Chascolytrum, Briza, Poidium, Calotheca, Microbriza, Gymnachne, Rhombolytrum, Lombardochloa and Erianthecium). Due to the remarkable morphological diversity, the relationships in Chascolytrum s.l. have remained poorly understood, and no infrageneric classification could be proposed based on the latest molecular phylogenetic studies. In this study, we combined molecular (GBSSI, trnL-trnL-trnF and rps16 intron) and morphological characters to investigate the phylogenetic relationships in Chascolytrum s.l. Based on this, morphologically diagnosable clades were recognized as eight sections (Calotheca, Chascolytrum, Hildaea, Lombardochloa, Microbriza, Obovatae, Poidium and Tricholemma), of which three are new and three are monospecific. We describe each section and discuss the new infrageneric classification in comparison with the previous infrageneric classification proposed for the group under the genus Briza. A taxonomic key and images for most of the species in each section are provided. Last, the use of single-copy nuclear genes and morphological data for future phylogenetic reconstructions encompassing Chascolytrum is highlighted.
Effect of vacuum-carbonization treatment of soft carbon anodes derived from coal-based mesophase pitch for lithium-ion batteries
Authors: Pan Guanghong , Liang Wenbin , Liang Peng , Chen Quanbin
Published: July 2019

Development of new power anode material with both high capacity and high-rate capability for lithium-ion batteries is highly desired. In this paper, a novel soft carbon anode for rechargeable lithium-ion batteries was developed using coal-based mesophase pitch. The structures of the materials were characterized by X-ray diffraction (XRD), Raman, N2 adsorption–desorption, Scanning Electron Microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The electrochemical characteristics of the new anode material were investigated. It was found that the soft carbon anode from coal-based mesophase pitch carbonized under vacuum conditions can deliver higher energy density and higher rate capability compared to soft carbon carbonized under a nitrogen atmosphere. The enhanced electrochemical properties are attributed to smaller nanocrystallites, more porosity, defects and carbon species of the resulting anode material.
Vertical Fiscal Externalities and Federal Tax-Transfers under Variable Factor Supplies
Authors: Tsakiris Nikos , Hatzipanayotou Panos , Michael Michael S
Published: July 2019

Within a model of variable supply of capital due to international mobility and variable labor supply due to endogenous labor-leisure choice, we revisit the issues of vertical fiscal externalities, and of federal tax-transfers. Capital and labor taxes by federal and state governments finance the provision of federal and of state public consumption goods. When capital and labor are substitutes in production, we show that (i) the state’s optimal policy calls for capital and labor taxes, (ii) the vertical fiscal externality can be reversed from negative, implying inefficiently high noncooperative capital taxes, to positive, implying inefficiently low noncooperative capital taxes, and (iii) under centralized leadership the federal government replicates the second best optimum with a capital tax, and possibly, top-down transfers. (JEL codes: F18, F21, H21).
Influencer identification in dynamical complex systems
Authors: Pei Sen , Wang Jiannan , Morone Flaviano , Makse Hernán A
Published: July 2019

The integrity and functionality of many real-world complex systems hinge on a small set of pivotal nodes, or influencers. In different contexts, these influencers are defined as either structurally important nodes that maintain the connectivity of networks, or dynamically crucial units that can disproportionately impact certain dynamical processes. In practice, identification of the optimal set of influencers in a given system has profound implications in a variety of disciplines. In this review, we survey recent advances in the study of influencer identification developed from different perspectives, and present state-of-the-art solutions designed for different objectives. In particular, we first discuss the problem of finding the minimal number of nodes whose removal would breakdown the network (i.e. the optimal percolation or network dismantle problem), and then survey methods to locate the essential nodes that are capable of shaping global dynamics with either continuous (e.g. independent cascading models) or discontinuous phase transitions (e.g. threshold models). We conclude the review with a summary and an outlook.
Aortic valve replacement-induced changes in native T1 are related to prognosis in severe aortic stenosis: T1 mapping cardiac magnetic resonance imaging study
Authors: Hwang In-Chang , Kim Hyung-Kwan , Park Jun-Bean , Park Eun-Ah , Lee Whal , Lee Seung-Pyo , Kim Yong-Jin , Sohn Dae-Won , Oh Jae K
Published: July 2019

Aims

Native T1 times from T1 mapping cardiac magnetic resonance (CMR) are associated with myocardial fibrosis in aortic stenosis (AS). We investigated whether changing patterns in native T1 predict clinical outcomes after aortic valve replacement (AVR) in severe AS patients.

Methods and results

Forty-three patients with severe AS (65.9 ± 8.1 years; 24 men) who underwent T1 mapping CMR at baseline and 1 year after AVR were prospectively enrolled. Upper limit of native T1 from healthy volunteers was used to define normal myocardium and diffuse fibrosis (native T1 < 1208.4 and ≥1208.4 ms, respectively). Participants were categorized into Group 1 (pre- and post-AVR normal myocardium; n = 11), Group 2 (pre-AVR diffuse fibrosis and post-AVR normal myocardium; n = 18), and Group 3 (post-AVR diffuse fibrosis; n = 14). Native T1 significantly decreased 1 year after AVR (pre-AVR, 1233.8 ± 49.7 ms; post-AVR, 1189.1 ± 58.4 ms; P < 0.001), which was associated with left ventricular (LV) mass regression (△native T1 vs. △LV mass index, r = 0.454, P = 0.010) and systolic function improvement (△native T1 vs. △LV ejection fraction, r = −0.379, P = 0.012). Group 2 showed greater functional improvements, whereas these benefits were blunted in Group 3. Group 3 had significantly worse outcomes than Group 1 [hazard ratio (HR), 9.479, 95% confidence interval (CI) 1.176–76.409; P = 0.035] and Group 2 (HR 3.551, 95% CI 1.178–10.704; P = 0.024).

Conclusion

AVR-induced changes in native T1 values are associated with LV systolic functional changes as well as prognosis in severe AS. Post-AVR T1 mapping CMR can be used as an imaging biomarker.
Prolonged mental health sequelae among doctors and nurses involved in patient safety incidents with formal complaints and lawsuits
Authors: Zeeman Gerda , Schouten Loes , Seys Deborah , Coeckelberghs Ellen , Weijenborg Philomeen , Bruyneel Luk , Vanhaecht Kris
Published: July 2019

We evaluated the presence of prolonged mental health sequelae in the aftermath of a patient safety incident and the impact of a formal complaint or lawsuit on these mental health sequelae in 19 hospitals and 2635 nurses and doctors. Of 2635 respondents, 983 (37.3%) reported a complaint and 190 (7.2%) reported a lawsuit. In both doctors and nurses prolonged mental health sequelae reflecting a stressor-related disorder were highly prevalent, each well over 20% overall. They were consistently more prevalent in case of a formal complaint or lawsuit. Lawsuits showed 2-, 3- and 4-fold increases in prevalence of mental health sequelae.
Neighborhood Experiences of People Over Age 50: Factor Structure and Validity of a Scale
Authors: Gan Daniel Rong Yao , Fung John Chye , Cho Im Sik
Published: July 2019

Background and Objectives

Various aspects of the neighborhood environment have been shown to correlate with older adults’ health. Socio-ecological models of health posit that interventions in the living environment can influence population health. Yet, there are no scales to comprehensively measure older people’s experiences of their neighborhoods especially in dense urban contexts. This study analyzes the psychometric properties and factor structure of a holistic measure of Older People’s Neighborhood Experience (OpenX) to understand constituent factors of residential satisfaction and well-being in dense urban contexts.

Research Design and Methods

Participants were 1,011 community-dwelling older adults aged 50 and older in Singapore. Face-to-face interviews were conducted. Questions were drawn to measure physical and social aspects of the neighborhood as well as sociodemographic variables. Exploratory and confirmatory factor analyses were conducted to obtain a shorter version; content validity, internal consistency, and external validity were assessed.

Results

The OpenX has a 4-dimensional structure, explaining 45.5% of the variance of neighborhood experience. They are communal affordance, embeddedness, environment pleasantness, and time outdoors. Good reliability and validity were found, including Cronbach’s alpha of 0.827. The correlation between neighborhood experience and objectively measured proximity to parks and fitness corners approached significance (p = .082).

Discussion and Implications

The 16-item OpenX demonstrated good psychometric properties. With reference to the transdisciplinary neighborhood health framework, it is useful for assessing older adults’ neighborhood environment, identifying neighborhoods for pilot population health interventions, and understanding how the neighborhood environment affects older adults’ health.
Developing the Person–Place Fit Measure for Older Adults: Broadening Place Domains
Authors: Weil Joyce
Published: July 2019

Background and Objectives

Literature calls for larger studies with empirically tested instruments about the meaning of place for older adults—studies that include a broader range of domains and neighborhood characteristics. Although rich narrative and qualitative data for small groups of older individuals exist, a measure with valid and reliable scores that includes the new, multiple domains about aging in place does not.

Research Design and Methods

Findings are reported from a two-phase, nine-step, exploratory sequential mixed-methods process of measurement development for the Person-Place Fit Measure for Older Adults (PPFM-OA). In Phase I, a focus group (n = 8) and qualitative interviews (n = 77) with persons 65 and older were used to develop emerging domains of aging in place. Qualitative data about concepts and language informed the development of a quantitative item pool for the Mechanical Turk-distributed survey. Phase II included a Delphi process reducing the number of items in the PPFM-OA. Exploratory factor analysis (EFA) and reliability analysis further reduced the number of potential measure items.

Results

Five factors emerged from the EFA. They were primary or basic needs/necessities (α = .84), neighborhood changes and moving (α = .88), identity and place attachment (α = .86), community value (α = .89), and services and resources (α = .78).

Discussion and Implications

The development of a measure, such as the PPFM-OA, is crucial as more programs and services are created to address aging in place but uniform data for planning and evaluation are lacking. These initial quantitative analyses are informative for the next step, a larger-scale, quantitative evaluation.
Regulation of phagolysosomal activity by miR-204 critically influences structure and function of retinal pigment epithelium/retina
Authors: Zhang Congxiao , Miyagishima Kiyoharu J , Dong Lijin , Rising Aaron , Nimmagadda Malika , Liang Genqing , Sharma Ruchi , Dejene Roba , Wang Yuan , Abu-Asab Mones , Qian Haohua , Li Yichao , Kopera Megan , Maminishkis Arvydas , Martinez Jennifer , Miller Sheldon
Published: July 2019

MicroRNA-204 (miR-204) is expressed in pulmonary, renal, mammary and eye tissue, and its reduction can result in multiple diseases including cancer. We first generated miR-204−/− mice to study the impact of miR-204 loss on retinal and retinal pigment epithelium (RPE) structure and function. The RPE is fundamentally important for maintaining the health and integrity of the retinal photoreceptors. miR-204−/− eyes evidenced areas of hyper-autofluorescence and defective photoreceptor digestion, along with increased microglia migration to the RPE. Migratory Iba1+ microglial cells were localized to the RPE apical surface where they participated in the phagocytosis of photoreceptor outer segments (POSs) and contributed to a persistent build-up of rhodopsin. These structural, molecular and cellular outcomes were accompanied by decreased light-evoked electrical responses from the retina and RPE. In parallel experiments, we suppressed miR-204 expression in primary cultures of human RPE using anti-miR-204. In vitro suppression of miR-204 in human RPE similarly showed abnormal POS clearance and altered expression of autophagy-related proteins and Rab22a, a regulator of endosome maturation. Together, these in vitro and in vivo experiments suggest that the normally high levels of miR-204 in RPE can mitigate disease onset by preventing generation of oxidative stress and inflammation originating from intracellular accumulation of undigested photoreactive POS lipids. More generally, these results implicate RPE miR-204-mediated regulation of autophagy and endolysosomal interaction as a critical determinant of normal RPE/retina structure and function.
Novel use of COMET parameters of sperm DNA damage may increase its utility to diagnose male infertility and predict live births following both IVF and ICSI
Authors: Nicopoullos James , Vicens-Morton Andrew , Lewis Sheena E M , Lee Kathryn , Larsen Peter , Ramsay Jonathan , Yap Tet , Minhas Suks
Published: July 2019

STUDY QUESTION

Do the Comet parameters of the proportions of sperm with low or high DNA damage improve the power of the test in the diagnosis of male infertility and/or prediction of IVF and ICSI live birth rates?

SUMMARY ANSWER

The mean Comet score and the scores for proportions of sperm with high or low DNA damage were useful in diagnosing male infertility and provided additional discriminatory information for the prediction of both IVF and ICSI live births.

WHAT IS KNOWN ALREADY

Sperm DNA damage impacts adversely on male fertility and IVF outcomes.

STUDY DESIGN, SIZE, DURATION

A retrospective study was performed involving a total of 457 participants (381 patients and 76 fertile donors). Data was collected from a fertility clinic between 2015 and 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 381 consecutive male partners of couples attending for ART and 76 fertile donors were included in the study. DNA fragmentation was measured by the alkaline Comet assay. Receiver operator characteristic curve analysis (area under the ROC curve (AUC)) was used to determine the value of average Comet score (ACS), low Comet score (LCS) and high Comet score (HCS) to diagnose male factor infertility. In total, 77 IVF and 226 ICSI cycles were included to determine thresholds for each parameter (AUC analysis) and to compare live birth rates (LBRs) following each ART.

MAIN RESULTS AND THE ROLE OF CHANCE

ACS, HCS and LCS were predictive of male infertility (AUC > 0.9, P < 0.0001). IVF LBRs declined once DNA damage exceeded the threshold levels. HCS showed the sharpest decline. Following ICSI, the highest LBRs were in men whose DNA damage levels approached the fertile range. Trends differed in IVF. LBRs decreased as damage increased whereas in ICSI the LBRs decreased but then remained stable.

LIMITATIONS, REASONS FOR CAUTION

Since this is the first study to show the impact of sperm DNA damage on ICSI live births, a prospective study should be performed (stratifying patients to IVF or ICSI based on these thresholds) to validate this study.

WIDER IMPLICATIONS OF THE FINDINGS

Our study presents novel information towards elucidating the genetic basis of male infertility and secondly on relevance of the extent of DNA damage as an impending factor in both IVF and ICSI success.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by Examenlab Ltd, The Lister Clinic, Cryos International and Imperial College London NHS Trust. No external funding was obtained for this study. SL and KL are employees of Examenlab Ltd, a university spin-out company with a commercial interest in sperm DNA damage. No other author has a conflict of interest to declare.

TRIAL REGISTRATION NUMBER

Non-applicable.
Private Actors as Transnational Regulators: The Case of Freedom of Association
Authors: Menashe Maayan
Published: July 2019

This article examines whether content of international public norms is significantly altered when embedded in transnational private labour regulations (TPLR); and, if it is, whether these alterations enrich or weaken the effect of these norms. Through a case study of freedom of association as regulated in five major TPLR initiatives, this research pursues a textual analysis of TPLR generated norms, to evaluate their content and to assess the nature of any modifications of international labour law norms. The findings reveal that although TPLR instruments are generally perceived as merely implementing internationally accepted norms, they in fact have a substantial norm-generating role, actively shaping the content of the norms they apply. The evidence further indicates that private actors can contribute to the design of innovative norms. At the same time, it was found that corporations had in several instances exerted negative influences over freedom of association norms and that when additional actors participated in the regulatory process, this right was better fulfilled. In addition, although meaningful participation of public actors in private regulatory initiatives was found to effectively prevent the undermining of the right to freedom of association, global union federations were less successful in this regard.
Maintaining progress for the most beautiful chart in the world
Authors: Hay Simon I
Published: July 2019

The decline in child mortality over the past two decades has been described as the greatest story in global public health. Indeed, using modern tools and interventions, there has been remarkable progress, reducing deaths in children <5 y of age by nearly half from 2000 to 2017. However, as a consequence of persistent geographic inequalities, we fall short of the United Nations Sustainable Development Goal to end all preventable child deaths by 2030, with an estimated 44.6 million preventable deaths expected to occur by the target year. This article discusses how we might further improve the downward trend in child mortality over the next decade to end preventable child deaths.
Social Ties and the Strategy of Civil Resistance
Authors: Thurber Ches
Published: July 2019

This article examines the impact of social ties on a challenger's ability to initiate a civil resistance campaign. Recent waves of nonviolent uprisings, from the color revolutions of Eastern Europe to the Arab Spring, have sparked renewed scholarly interest in civil resistance as a strategy in conflict. However, most research has focused on the effectiveness and outcomes of civil resistance, with less attention paid to when, why, and how challengers to regime power come to embrace a strategy of nonviolent action in the first place. Drawing upon a longitudinal analysis of challenger organizations and coalitions in Nepal, this article illustrates how social ties inform challengers’ assessments of the viability of civil resistance and consequently shape their strategic behavior. The findings complicate state-centric approaches to contentious politics by showing how diverse actors within the same state face different sets of political opportunities and constraints. They also highlight the indeterminate effects of ideology, as variation in challengers’ social ties drive Gandhians to take up arms and Maoists to lay them down.
Method for Postmortem Quantification of Δ9-Tetrahydrocannabinol and Metabolites Using LC–MS–MS
Authors: Al-Asmari Ahmed I
Published: July 2019

A specific, sensitive, fast and simple method for analysis of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-THC (THC-OH) and 11-nor-Δ9-THC-9-carboxylic acid (THC-COOH) in routine postmortem cases using LC–MS–MS was developed and validated. Prior to solid phase extraction, urine, stomach contents and bile were pretreated using alkaline hydrolysis, while blood and vitreous humor were pretreated with protein precipitation. The distribution of THC, THC-OH and THC-COOH were investigated in 31 postmortem cases that tested positive for cannabinoids. This revealed new information regarding the distribution of THC in stomach contents and vitreous humor. Alkaline hydrolysis was sufficient for the deglucuronidation of THC-COOH-glucuronide to its free form, THC-COOH, in urine, bile and stomach contents. However, the THC-OH concentration in bile reported in this study is considerably high compared to that of previous studies. In conclusion, including THC and its metabolites (THC-OH and THC-COOH) is crucial for any forensic toxicology detection method to most accurately determine the role of cannabinoids in deaths.
Language Loss and Illocutionary Silencing
Authors: Nowak Ethan
Published: July 2019

The twenty-first century will witness an unprecedented decline in the diversity of the world’s languages. While most philosophers will likely agree that this decline is lamentable, the question of what exactly is lost with a language has not been systematically explored in the philosophical literature. In this paper, I address this lacuna by arguing that language loss constitutes a problematic form of illocutionary silencing. When a language disappears, past and present speakers lose the ability to realize a range of speech acts that can only be realized in that language. With that ability, speakers lose something in which they have a fundamental interest: their standing as fully empowered members of a linguistic community.
In-vitro differentiation of early pig spermatogenic cells to haploid germ cells
Authors: Yu Kun , Zhang Yi , Zhang Bao-Lu , Wu Han-Yu , Jiang Wu-Qi , Wang Su-Tian , Han De-Ping , Liu Yi-Xun , Lian Zheng-Xing , Deng Shou-Long
Published: July 2019

Spermatogonial stem cells (SSCs) self-renew and contribute genetic information to the next generation. Pig is wildly used as a model animal for understanding reproduction mechanisms of human being. Inducing directional differentiation of porcine SSCs may be an important strategy in exploring the mechanisms of spermatogenesis and developing better treatment methods for male infertility. Here, we established an in-vitro culture model for porcine small seminiferous tubule segments, to induce SSCs to differentiate into single-tail haploid spermatozoa. The culture model subsequently enabled spermatozoa to express the sperm-specific protein acrosin and oocytes to develop to blastocyst stage after round spermatid injection. The addition of retinoic acid (RA) to the differentiation media promoted the efficiency of haploid differentiation. RT-PCR analysis indicated that RA stimulated the expression of Stra8 but reduced the expression of NANOS2 in spermatogonia. Genes involved in post-meiotic development, transition protein 1 (Tnp1) and protamine 1 (Prm1) were upregulated in the presence of RA. The addition of an RA receptor (RAR) inhibitor, BMS439, showed that RA enhanced the expression of cAMP responsive-element binding protein through RAR and promoted the formation of round spermatids. We established an efficient culture system for in-vitro differentiation of pig SSCs. Our study represents a model for human testis disease and toxicology screening. Molecular regulators of SSC differentiation revealed in this study might provide a therapeutic strategy for male infertility.
DAXX in cancer: phenomena, processes, mechanisms and regulation
Authors: Mahmud Iqbal , Liao Daiqing
Published: July 2019

DAXX displays complex biological functions. Remarkably, DAXX overexpression is a common feature in diverse cancers, which correlates with tumorigenesis, disease progression and treatment resistance. Structurally, DAXX is modular with an N-terminal helical bundle, a docking site for many DAXX interactors (e.g. p53 and ATRX). DAXX’s central region folds with the H3.3/H4 dimer, providing a H3.3-specific chaperoning function. DAXX has two functionally critical SUMO-interacting motifs. These modules are connected by disordered regions. DAXX’s structural features provide a framework for deciphering how DAXX mechanistically imparts its functions and how its activity is regulated. DAXX modulates transcription through binding to transcription factors, epigenetic modifiers, and chromatin remodelers. DAXX’s localization in the PML nuclear bodies also plays roles in transcriptional regulation. DAXX-regulated genes are likely important effectors of its biological functions. Deposition of H3.3 and its interactions with epigenetic modifiers are likely key events for DAXX to regulate transcription, DNA repair, and viral infection. Interactions between DAXX and its partners directly impact apoptosis and cell signaling. DAXX’s activity is regulated by posttranslational modifications and ubiquitin-dependent degradation. Notably, the tumor suppressor SPOP promotes DAXX degradation in phase-separated droplets. We summarize here our current understanding of DAXX’s complex functions with a focus on how it promotes oncogenesis.
Systems biology-based investigation of cooperating microRNAs as monotherapy or adjuvant therapy in cancer
Authors: Lai Xin , Eberhardt Martin , Schmitz Ulf , Vera Julio
Published: July 2019

MicroRNAs (miRNAs) are short, noncoding RNAs that regulate gene expression by suppressing mRNA translation and reducing mRNA stability. A miRNA can potentially bind many mRNAs, thereby affecting the expression of oncogenes and tumor suppressor genes as well as the activity of whole pathways. The promise of miRNA therapeutics in cancer is to harness this evolutionarily conserved mechanism for the coordinated regulation of gene expression, and thus restoring a normal cell phenotype. However, the promiscuous binding of miRNAs can provoke unwanted off-target effects, which are usually caused by high-dose single-miRNA treatments. Thus, it is desirable to develop miRNA therapeutics with increased specificity and efficacy. To achieve that, we propose the concept of miRNA cooperativity in order to exert synergistic repression on target genes, thus lowering the required total amount of miRNAs. We first review miRNA therapies in clinical application. Next, we summarize the knowledge on the molecular mechanism and biological function of miRNA cooperativity and discuss its application in cancer therapies. We then propose and discuss a systems biology approach to investigate miRNA cooperativity for the clinical setting. Altogether, we point out the potential of miRNA cooperativity to reduce off-target effects and to complement conventional, targeted, or immune-based therapies for cancer.