bluuebunny/crossref_metadata_2025 huggingface dataset:
The culture, mental health and psychosocial wellbeing of Rohingya refugees: a systematic review
Authors: Tay A. K. , Riley A. , Islam R. , Welton-Mitchell C. , Duchesne B. , Waters V. , Varner A. , Moussa B. , Mahmudul Alam A. N. M. , Elshazly M. A. , Silove D. , Ventevogel P.
Published: April 2019

Aims

Despite the magnitude and protracted nature of the Rohingya refugee situation, there is limited information on the culture, mental health and psychosocial wellbeing of this group. This paper, drawing on a report commissioned by the United Nations High Commissioner for Refugees (UNHCR), aims to provide a comprehensive synthesis of the literature on mental health and psychosocial wellbeing of Rohingya refugees, including an examination of associated cultural factors. The ultimate objective is to assist humanitarian actors and agencies in providing culturally relevant Mental Health and Psychosocial Support (MHPSS) for Rohingya refugees displaced to Bangladesh and other neighbouring countries.

Methods

We conducted a systematic search across multiple sources of information with reference to the contextual, social, economic, cultural, mental health and health-related factors amongst Rohingya refugees living in the Asia-Pacific and other regions. The search covered online databases of diverse disciplines (e.g. medicine, psychology, anthropology), grey literature, as well as unpublished reports from non-profit organisations and United Nations agencies published until 2018.

Results

The legacy of prolonged exposure to conflict and persecution compounded by protracted conditions of deprivations and displacement is likely to increase the refugees' vulnerability to wide array of mental health problems including posttraumatic stress disorder, anxiety, depression and suicidal ideation. High rates of sexual and gender-based violence, lack of privacy and safe spaces and limited access to integrated psychosocial and mental health support remain issues of concern within the emergency operation in Bangladesh. Another challenge is the limited understanding amongst the MHPSS personnel in Bangladesh and elsewhere of the language, culture and help-seeking behaviour of Rohingya refugees. While the Rohingya language has a considerable vocabulary for emotional and behavioural problems, there is limited correspondence between these Rohingya terms and western concepts of mental disorders. This hampers the provision of culturally sensitive and contextually relevant MHPSS services to these refugees.

Conclusions

The knowledge about the culture, context, migration history, idioms of distress, help-seeking behaviour and traditional healing methods, obtained from diverse sources can be applied in the design and delivery of culturally appropriate interventions. Attention to past exposure to traumatic events and losses need to be paired with attention for ongoing stressors and issues related to worries about the future. It is important to design MHPSS interventions in ways that mobilise the individual and collective strengths of Rohingya refugees and build on their resilience.
Signatures of Thermospheric‐Exospheric Coupling of Hydrogen in Observed Seasonal Trends of H α Intensity
Authors: Gallant M. A. , Mierkiewicz E. J. , Nossal S. M. , Qian L. , Burns A. G. , Zacharias A. R. , Roesler F. L.
Published: April 2019

Analysis of an established geocoronal H α data set indicates a seasonal trend in observed dusk‐to‐dawn intensity variation, consistent with a diurnal variation in the underlying thermospheric hydrogen density. Observations were obtained at Pine Bluff Observatory, WI, from 2000 to 2001 using a high spectral resolution (R∼80,000) Fabry‐Perot annular summing spectrometer. This dusk‐to‐dawn asymmetry in intensity is highest in winter months with a difference of ∼2.7 Rayleighs and smallest in summer months with a difference of ∼0.5 Rayleighs; observations near equinox show a dusk‐to‐dawn difference in intensity close to ∼1.3 Rayleighs. Comparisons between modeled and observed dusk‐to‐dawn intensity variation show good agreement near the equinoxes. The modeled intensity was generated using the lyao_rt radiative transport code of Bishop (1999, https://doi.org/10.1016/S0022-4073(98)00031-4), employing NRLMSISE‐00 thermospheric hydrogen profiles extended into the exosphere via the evaporative case of the Bishop analytic exosphere. Near the equinoxes and summer solstice, the model tends to agree with observations. Near the winter solstice, the model underestimates the dusk‐to‐dawn asymmetry by 1.5–2 Rayleighs. Overall, modeled H α intensity generated with NRLMSISE‐00 as the thermospheric input is shown to be consistently lower than observed intensity by a factor of ∼2.
Development and Verification of a Numerical Library for Solving Global Terrestrial Multiphysics Problems
Authors: Bisht Gautam , Riley William J.
Published: April 2019

Current generation Land Surface Models (LSMs) routinely simulate many nonlinear multiphysics processes. The complexity of future generation LSMs is expected to increase as critical new biophysical and biogeochemical processes are incorporated. Current generation LSMs have several shortcomings including the lack of robust numerical methods to solve discretized equations, monolithic software design that hinders testing of a process representation in isolation from other components, and absence of a flexible coupling framework to solve tightly coupled multiphysics problems. While the LSMs community vigorously evaluates the accuracy of the conceptual model to represent reality (validation), the accuracy of the numerical implementation of the conceptual model (verification) is seldom examined. Method of Manufactured Solutions is a technique for verifying complex codes when analytical solutions are unavailable. In this work, we present a stand‐alone, open source numerical library for solving global terrestrial multiphysics processes that includes a flexible coupling framework. Robust numerical solution for linear and nonlinear equations is provided via the Portable, Extensible Toolkit for Scientific Computation library. We verify the numerical library using Method of Manufactured Solutions for a range of problems comprising single and multiphysics steady state problems that are applied in one or multiple physical domains. This work provides an example of incorporating code verification as an integral part of Land Surface Model development activities.
Evaluation of Clouds in Version 1 of the E3SM Atmosphere Model With Satellite Simulators
Authors: Zhang Yuying , Xie Shaocheng , Lin Wuyin , Klein Stephen A. , Zelinka Mark , Ma Po‐Lun , Rasch Philip J. , Qian Yun , Tang Qi , Ma Hsi‐Yen
Published: April 2019

This study systematically evaluates clouds simulated by the Energy Exascale Earth System Model Atmosphere Model version 1 (EAMv1) against satellite cloud observations. Both low‐ (1°) and high‐ (0.25°) resolution EAMv1 configurations generally underestimate clouds in low latitudes and midlatitudes and overestimate clouds in the Arctic, although the error is smaller in the high‐resolution model. The underestimate of clouds is due to the underestimate of optically thin to intermediate clouds, as EAMv1 generally overestimates optically intermediate to thick clouds. Other model errors include the largely underpredicted marine stratocumulus along the coasts and high clouds over the tropical deep convection regions. The underestimate of thin clouds results in too much longwave radiation being emitted to space and too little shortwave radiation being reflected back to space, while the overestimate of optically intermediate and thick clouds leads to too little longwave radiation being emitted to space and too much shortwave radiation being reflected back to space. EAMv1 shows better skill in reproducing the observed distribution of clouds and their properties and has smaller radiatively relevant errors in the distribution of clouds than most of the CFMIP1 and CFMIP2 models. It produces more supercooled liquid cloud fraction than CAM5 and most CMIP5 models primarily due to a new ice nucleation scheme and secondarily due to a reduction of the ice deposition growth rate.
Cosmetic penile enhancement surgery: a 3-year single-centre retrospective clinical evaluation of 355 cases
Authors: Littara Alessandro , Melone Roberto , Morales-Medina Julio Cesar , Iannitti Tommaso , Palmieri Beniamino
Published: April 2019

Men’s satisfaction and sexual function is influenced by discomfort over genital size which leads to seek surgical and non-surgical solutions for penis alteration. In this article we report the results of a retrospective study of 355 cases of cosmetic elongation, enlargement and combined elongation and enlargement phalloplasty. We found a significant improvement in length at rest, stretched length and circumference at rest at 2, 6 and 12 months post-surgical procedure (all p < 0.0001). 5-item International Index of Erectile Function (IIEF-5) was also increased at 12 months post-surgery compared to baseline (p < 0.0001). This was consistent with an IIEF-5 improvement of 6.74% compared to baseline. This study is clinically relevant due to the large cohort of patients included and because it is the first study to use an inverse periosteal-fascial suture not described previously as part of the surgical methodology.
Publisher Correction: Diattenuation Imaging reveals different brain tissue properties
Authors: Menzel Miriam , Axer Markus , Amunts Katrin , De Raedt Hans , Michielsen Kristel
Published: April 2019

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Electrical percolation threshold of carbon black in a polymer matrix and its application to antistatic fibre
Authors: Choi Hyun-Jung , Kim Moo Sung , Ahn Damiro , Yeo Sang Young , Lee Sohee
Published: April 2019

In this study, using three types of resins (each with unique material properties) as a matrix, and carbon black (CB) as a conductive additive, conductive fibres were fabricated through a melt-spinning process. An examination of the electrical conductivity revealed that a CB/polyethylene terephthalate (PET) composite had a low percolation value of 0.58 wt%, and thus the highest conductivity of the three resin types. These results indicate that CB/PET fibres could be used to manufacture antistatic fabrics.
Cyclic permutations for qudits in d dimensions
Authors: Isdrailă Tudor-Alexandru , Kusko Cristian , Ionicioiu Radu
Published: April 2019

One of the main challenges in quantum technologies is the ability to control individual quantum systems. This task becomes increasingly difficult as the dimension of the system grows. Here we propose a general setup for cyclic permutations Xd in d dimensions, a major primitive for constructing arbitrary qudit gates. Using orbital angular momentum states as a qudit, the simplest implementation of the Xd gate in d dimensions requires a single quantum sorter Sd and two spiral phase plates. We then extend this construction to a generalised Xd(p) gate to perform a cyclic permutation of a set of d, equally spaced values {|$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

〉, |$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

 + p〉, …, |$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

 + (d − 1)p〉} $$\mapsto $$
↦
 {|$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

 + p〉, |$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

 + 2p〉, …, |$${{\boldsymbol{\ell }}}_{{\bf{0}}}$$

ℓ

0

〉}. We find compact implementations for the generalised Xd(p) gate in both Michelson (one sorter Sd, two spiral phase plates) and Mach-Zehnder configurations (two sorters Sd, two spiral phase plates). Remarkably, the number of spiral phase plates is independent of the qudit dimension d. Our architecture for Xd and generalised Xd(p) gate will enable complex quantum algorithms for qudits, for example quantum protocols using photonic OAM states.
On both magnetized and non-magnetized dual stratified medium via stream lines topologies: A generalized formulation
Authors: Rehman Khalil Ur , Malik M. Y. , Al-Mdallal Qasem M. , Zahri Mostafa
Published: April 2019

The major concern of current pagination is to report the doubly stratified medium subject to both magnetized and non-magnetized flow fields. For this purpose both the Newtonian and non-Newtonian liquids are considered in a double stratified medium having magnetic field interaction. To be more specific, a generally accepted rheological liquid around a cylindrical surface having constant radius embedded in magnetized doubly stratified media is taken into account. Additionally, flow field is manifested with various pertinent physical effects. The flow problem statement is defended through generalized formulation via fundamental laws. A computational scheme is executed and stream lines topologies are constructed for the both magnetized and non-magnetized stratified medium to explore the interesting features. It is observed that the Casson fluid velocity towards cylindrical surface is higher in magnitude as compared to flat surface. Such observation is same for the both the magnetized and non-magnetized flow fields. Our general formulation yields some existing attempts in the literature. The variations in local skin friction coefficient (LSFC), local Nusselt number (LNN) and local Sherwood number (LSN) are provided with the aid of tabular forms. It is trusted that the obtain observations via stream lines topologies will serve a clear insight to the said flow problem.
Morphometric analysis in mouse scleral fibroblasts using focused ion beam/scanning electron microscopy
Authors: Murata Kazuhisa , Hirata Akira , Ohta Keisuke , Enaida Hiroshi , Nakamura Kei-ichiro
Published: April 2019

The sclera as well as the cornea forms the principal part of the outer fibrous coat of the eye, with a primary function of protecting the intraocular contents and maintaining the shape of the globe. However, the exact morphometric arrangement of scleral fibroblasts remains unclarified. The aim of this study was to observe the three-dimensional structure of the mouse scleral fibroblasts by focused ion beam/scanning electron microscopy (FIB/SEM). Four eyes from C57BL/6J mice were fixed using a mixture of glutaraldehyde and formaldehyde. The sclera was cut out at the equatorial portion and the posterior pole, and postfixed with potassium ferrocyanide, osmium, thiocarbohydrazide, uranyl acetate and lead aspartate. Specimens were then dehydrated and embedded in an epoxy resin. Serial block face images were obtained using FIB/SEM. Three-dimensional image reconstruction and segmentation of the image stack were created using computer software (Amira v6.0.1, FEI). Scleral fibroblasts were arranged in collagenous layers. The cells frequently showed a cellular junction with the neighboring cells and formed cellular networks. Compared with equatorial fibroblasts, there was a more complicated cellular arrangement of the posterior scleral fibroblasts.
Comparative analysis of intestinal bacteria among venom secretion and non-secrection snakes
Authors: Qin Zuodong , Wang Siqi , Guo Dezhi , Zhu Jialiang , Chen Huahai , Bai Le , Luo Xiaofang , Yin Yeshi
Published: April 2019

To further investigate the bacterial community and identify the bacterial biomarkers between venom secretion and non-venom secretion snakes, 50 intestinal samples (25 large intestine, 25 small intestine) were obtained from 29 snakes (13 gut samples from Deinagkistrodon, 26 from Naja and 11 from Ptyas mucosa). 16S rDNA high-throughput sequencing results showed that 29 bacterial phyla, 545 bacterial genera, and 1,725 OTUs (operational taxonomic units) were identified in these samples. OTU numbers and the Ace, Chao, Shannon, and Simpson indexes were very similar among the three breeds of snakes included in this study. The Bacteroidetes, Firmicutes, Fusobacteria and Proteobacteria were predominant bacterial phyla. The relative abundance at the phylum level among these samples was similar, and the difference between small and large intestinal samples was not obvious. However, at the genus level, venom secretion snakes Deinagkistrodon and Naja clustered together according to different breeds. 27, 24, and 16 genera were identified as core microbes for Deinagkistrodon, Naja, and Ptyas mucosa, respectively. Interestingly, the relative abundances of genera Hafnia_Obesumbacterium, Providencia, and Ureaplasma were found to be significantly higher in non-venom secretion snakes, and the genera Achromobacter, Cetobacterium, Clostridium innocuum group, Fusobacterium, Lachnoclostridium, Parabacteroides, and Romboutsia were only detected in venom secretion snakes. The function of these bacteria in venom secretion needs to be further studied, and these venom secretion related genera may be the promising target to improve venom production.
Modelling changes in glutathione homeostasis as a function of quinone redox metabolism
Authors: Kelly Ross A. , Leedale Joseph , Calleja Dominic , Enoch Steven J. , Harrell Andy , Chadwick Amy E. , Webb Steven
Published: April 2019

Redox cycling is an understated mechanism of toxicity associated with a plethora of xenobiotics, responsible for preventing the effective treatment of serious conditions such as malaria and cardiomyopathy. Quinone compounds are notorious redox cyclers, present in drugs such as doxorubicin, which is used to treat a host of human cancers. However, the therapeutic index of doxorubicin is undermined by dose-dependent cardiotoxicity, which may be a function of futile redox cycling. In this study, a doxorubicin-specific in silico quinone redox metabolism model is described. Doxorubicin-GSH adduct formation kinetics are thermodynamically estimated from its reduction potential, while the remainder of the model is parameterised using oxygen consumption rate data, indicative of hydroquinone auto-oxidation. The model is then combined with a comprehensive glutathione metabolism model, facilitating the simulation of quinone redox cycling, and adduct-induced GSH depletion. Simulations suggest that glutathione pools are most sensitive to exposure duration at pharmacologically and supra-pharmacologically relevant doxorubicin concentrations. The model provides an alternative method of investigating and quantifying redox cycling induced oxidative stress, circumventing the experimental difficulties of measuring and tracking radical species. This in silico framework provides a platform from which GSH depletion can be explored as a function of a compound’s physicochemical properties.
Anthropogenic Effects on Natural Mammalian Populations: Correlation Between Telomere Length and Coal Exposure
Authors: Matzenbacher Cristina A. , Da Silva Juliana , Garcia Ana Leticia H. , Cappetta Mónica , de Freitas Thales R. O.
Published: April 2019

The Candiota coal mine in Rio Grande do Sul (RS) is one of the largest in Brazil. Coal is a fossil fuel that causes environmental impacts from its extraction to combustion due to the release of different agents, such as polycyclic aromatic hydrocarbons (PAH) and heavy metals. Ctenomys torquatus are herbivorous and subterranean rodents that dig tunnels with their paws and teeth and can be exposed to coal through contaminated food. Exposure to pollutants can cause DNA damage and affect different tissues, inducing alterations in the population structure and genetic diversity. Our study aimed to evaluate the effect of exposure to coal and its derivatives on the C. torquatus population and to examine the relationship of coal exposure with variations in absolute telomere length (aTL), global DNA methylation and genotoxicity. Our study showed an inverse correlation between telomere length and coal exposure in addition to an increase in DNA damage. The results indicate that coal and its byproducts can contribute to the alteration of the C. torquatus population structure, as evidenced by a reduction in the number of adults.
Assessment of Glyphosate Induced Epigenetic Transgenerational Inheritance of Pathologies and Sperm Epimutations: Generational Toxicology
Authors: Kubsad Deepika , Nilsson Eric E. , King Stephanie E. , Sadler-Riggleman Ingrid , Beck Daniel , Skinner Michael K.
Published: April 2019

Ancestral environmental exposures to a variety of factors and toxicants have been shown to promote the epigenetic transgenerational inheritance of adult onset disease. One of the most widely used agricultural pesticides worldwide is the herbicide glyphosate (N-(phosphonomethyl)glycine), commonly known as Roundup. There are an increasing number of conflicting reports regarding the direct exposure toxicity (risk) of glyphosate, but no rigorous investigations on the generational actions. The current study using a transient exposure of gestating F0 generation female rats found negligible impacts of glyphosate on the directly exposed F0 generation, or F1 generation offspring pathology. In contrast, dramatic increases in pathologies in the F2 generation grand-offspring, and F3 transgenerational great-grand-offspring were observed. The transgenerational pathologies observed include prostate disease, obesity, kidney disease, ovarian disease, and parturition (birth) abnormalities. Epigenetic analysis of the F1, F2 and F3 generation sperm identified differential DNA methylation regions (DMRs). A number of DMR associated genes were identified and previously shown to be involved in pathologies. Therefore, we propose glyphosate can induce the transgenerational inheritance of disease and germline (e.g. sperm) epimutations. Observations suggest the generational toxicology of glyphosate needs to be considered in the disease etiology of future generations.
Additive effects of inhibiting both mTOR and glutamine metabolism on the arthritis in SKG mice
Authors: Ueda Yo , Saegusa Jun , Okano Takaichi , Sendo Sho , Yamada Hirotaka , Nishimura Keisuke , Morinobu Akio
Published: April 2019

Glutamine metabolism and the mechanistic target of rapamycin (mTOR) pathway are activated cooperatively in the differentiation and activation of inflammatory immune cells. But the combined inhibition of both pathways was rarely investigated. This study investigated how inhibiting both glutamine metabolism with 6-diazo-5-oxo-L-norleucine (DON) and mTOR with rapamycin affects immune cells and the arthritis in a mouse model. We revealed that rapamycin and DON additively suppressed CD4+ T cell proliferation, and both of them inhibited Th17 cell differentiation. While DON inhibited the differentiation of dendritic cells and macrophages and facilitated that of Ly6G+ granulocytic (G)-MDSCs more strongly than did rapamycin, G-MDSCs treated with rapamycin but not DON suppressed CD4+ T cell proliferation in vitro. The combination of rapamycin and DON significantly suppressed the arthritis in SKG mice more strongly than did each monotherapy in vivo. The numbers of CD4+ T and Th17 cells in the spleen were lowest in mice treated with the combination therapy. Thus, combined treatment with rapamycin and DON additively ameliorated the arthritis in SKG mice, possibly by suppressing CD4+ T cell proliferation and Th17 differentiation. These results suggest the combination of rapamycin and DON may be a potential novel therapy for arthritis.
High-solar-absorptance CSP coating characterization and reliability testing with isothermal and cyclic loads for service-life prediction
Authors: Noč Luka , Šest Ervin , Kapun Gregor , Ruiz-Zepeda Francisco , Binyamin Yaniv , Merzel Franci , Jerman Ivan
Published: April 2019

Revealed degradation mechanisms in the HSA CSP coatings through accelerated testing and materials characterization enable absorber service life prediction.
On the stability of antimony doped tin oxide supports in proton exchange membrane fuel cell and water electrolysers
Authors: Jiménez-Morales Ignacio , Cavaliere Sara , Dupont Marc , Jones Deborah , Rozière Jacques
Published: April 2019

This study on bare and catalysed Sb–SnO2electrospun tubes allowed to determine the potential window for its optimal utilisation as electrocatalyst support in PEM fuel cells and water electrolysers: the stability of the oxide strongly depends on the existing surface segregation of Sb.
Control over the formation of supramolecular material objects using reaction–diffusion
Authors: Lovrak Matija , Hendriksen Wouter E. , Kreutzer Michiel T. , van Steijn Volkert , Eelkema Rienk , van Esch Jan H.
Published: April 2019

The ratio between diffusion and reaction time scales determines the size of soft matter objects made through self-assembly-coupled reaction–diffusion.
Widefield frequency domain fluorescence lifetime imaging microscopy (FD-FLIM) for accurate measurement of oxygen gradients within microfluidic devices
Authors: Wu Hsiao-Mei , Lee Tse-Ang , Ko Ping-Liang , Liao Wei-Hao , Hsieh Tung-Han , Tung Yi-Chung
Published: April 2019

A widefield FD-FLIM system with fast acquisition speed is utilized to accurately characterize oxygen gradient distributions within microfluidic devices.
An electrochemiluminescent aptasensor for amplified detection of exosomes from breast tumor cells (MCF-7 cells) based on G-quadruplex/hemin DNAzymes
Authors: Qiao Bin , Guo Qunqun , Jiang Juqian , Qi Yunlong , Zhang Hui , He Bangshun , Cai Chenxin , Shen Jian
Published: April 2019

An electrochemiluminescent aptasensor was developed for the sensitive detection of exosomes from breast tumor cells (MCF-7 cells).
Dual functional monomer surface molecularly imprinted microspheres for polysaccharide recognition in aqueous solution
Authors: Zhao Qianyu , Zhao Haitian , Huang Weiwei , Yang Xin , Yao Lei , Liu Jia , Li Jiaqi , Wang Jing
Published: April 2019

In this work, novel water-compatible core–shell surface molecularly imprinted polymers with double recognition abilities for highly efficient separation of starch polysaccharide were prepared.
ReGaGe2: an intermetallic compound with semiconducting properties and localized bonding
Authors: Likhanov Maxim S. , Khalaniya Roman A. , Verchenko Valeriy Yu. , Gippius Andrei A. , Zhurenko Sergei V. , Tkachev Alexey V. , Fazlizhanova Dina I. , Kuznetsov Alexey N. , Shevelkov Andrei V.
Published: April 2019

ReGaGe2is a new intermetallic compound with semiconducting properties and localized bonding patterns.
Feasible structure-modification strategy for inhibiting aggregation-caused quenching effect and constructing exciton conversion channels in acridone-based emitters
Authors: Wan Qing , Zhang Bing , Tong Jialin , Li Yin , Wu Haozhong , Zhang Han , Wang Zhiming , Pan Yuyu , Tang Ben Zhong
Published: April 2019

The introduction of multiple rotors donors and benzonitrile group in ADOs would increases effectively OLED emitters' performance by inhibiting aggregation-caused quenching effect and constructing exciton conversion channels.
Oxidative desulfurization in diesel via a titanium dioxide triggered thermocatalytic mechanism
Authors: Zuo Miaoguo , Huang Xiaoqiao , Li Jianxin , Chang Qian , Duan Yongsheng , Yan Lijun , Xiao Zaozao , Mei Shiduo , Lu Shuxiang , Yao Yue
Published: April 2019

TiO2 was prepared through a sol–gel method as the thermo-catalyst for oxidative desulfurization (ODS), and H2O2 was selected as the oxidant.
Tunable colloidal Ni nanoparticles confined and redistributed in mesoporous silica for CO2 methanation
Authors: Vrijburg Wilbert L. , van Helden Jolanda W. A. , van Hoof Arno J. F. , Friedrich Heiner , Groeneveld Esther , Pidko Evgeny A. , Hensen Emiel J. M.
Published: April 2019

Colloidal Ni nanoparticles were prepared using seed-mediated strategies and encapsulated in mesoporous silica to yield stable and sinter-resistant hydrogenation catalysts.
Significant geometry and charge difference between the E54− bare clusters of group 14 Zintl anions and their coordinated form in [E5{M(CO)3}2]4− (E = Si, Ge, Sn, Pb; M = Cr, Mo, W) complexes
Authors: Gholiee Yasin , Salehzadeh Sadegh , Khodaveisi Shiva
Published: April 2019

It is shown that while none of the E5n (E = Si, Ge, Sn, Pb; n = 0, 2−, 4−) bare clusters can be stabilized in planar pentagon (D5h) geometry, E54− ions as a five-membered planar ring form stable complexes with two {M(CO)3} (M = Cr, Mo, W) metal carbonyls. Interestingly, the negative charge of all [E5{M(CO)3}2]4− complexes is distributed on two {M(CO)3} fragments rather than the coordinated Zintl ion.
Kinetics and mechanism of the reaction of cyanocobalamin with potassium hydroxide in non-aqueous media
Authors: Salnikov D. S. , Makarov S. V.
Published: April 2019

The reaction of cyanocobalamin (CNCbl) with potassium hydroxide (KOH) was studied in isopropyl alcohol (iPrOH) and dimethyl sulfoxide (DMSO) under anaerobic conditions.
Structure-based rational design, synthesis, crystal structure, DFT and molecular docking of 1,4-benzene dicarboxamide isomers with application as hardeners
Authors: Teotia Meenu , Tarannum Nazia , Chauhan Mohit , Soni Rakesh Kumar
Published: April 2019

Molecular structures of two isomers have been investigated by SXRD analysis and DFT calculations and the isomers are assessed for their antimicrobial properties and as curing agents for epoxy resins.
Efficient and practical synthesis of unsymmetrical disulfidesviabase-catalyzed aerobic oxidative dehydrogenative coupling of thiols
Authors: Qiu Xu , Yang Xiaoxue , Zhang Yiqun , Song Song , Jiao Ning
Published: April 2019

A novel M2CO3-catalyzed aerobic oxidative heterocoupling of thiols with air as the oxidant was described for the synthesis of unsymmetrical disulfides. High atom economy, green catalyst and oxidant, mild reaction conditions, and broad substrate scope make this strategy extremely attractive.
Developments towards synthesis of N-heterocycles from amidinesviaC–N/C–C bond formation
Authors: Guo Wei , Zhao Mingming , Tan Wen , Zheng Lvyin , Tao Kailiang , Fan Xiaolin
Published: April 2019

This review focuses on the synthesis of N-heterocycles using amidines as starting materials, with an emphasis on the mechanisms of these reactionsviaC–N/C–C bond formation.
Using SeO2as a selenium source to make RSe-substituted aniline and imidazo[1,2-a]pyridine derivatives
Authors: Ren Yaokun , Xu Baojun , Zhong Zijian , Pittman Charles U. , Zhou Aihua
Published: April 2019

A mild and practical method is developed for the synthesis of ArSe-substituted aniline and imidazo[1,2-a]pyridine derivatives using SeO2as a selenium agent.
Discovery of non-classical complex models between a cationic water-soluble pillar[6]arene and naphthalenesulfonate derivatives and their self-assembling behaviors
Authors: Wang Mengbin , Zhou Jiong
Published: April 2019

Non-classical complex models of a cationic water-soluble pillar[6]arene with naphthalenesulfonate derivatives and their self-assembling behaviors were discovered.
Confining ultrasmall bimetallic alloys in porous N–carbon for use as scalable and sustainable electrocatalysts for rechargeable Zn–air batteries
Authors: Liu Jingjing , He Ting , Wang Qichen , Zhou Zhaoxi , Zhang Yaqian , Wu Huiqiong , Li Qiang , Zheng Jun , Sun Zhifang , Lei Yongpeng , Ma Jianmin , Zhang Yi
Published: April 2019

Ultrasmall bimetallic alloy nanoparticles are generated via a micro–mesopore confinement synthesis strategy in nanoporous N–carbon. The prepared catalysts show excellent bifunctional performance in both ORR and OER, and outstanding energy conversion efficiency in Zn–air batteries.
Novel benzodithiophene unit with an alkylthiobiphenyl side chain for constructing high-efficiency polymer solar cells
Authors: Li Xiaoming , Huang Gongyue , Jiang Huanxiang , Qiao Shanlin , Kang Xiao , Chen Weichao , Yang Renqiang
Published: April 2019

Polymer solar cells were studied by blending the prepared novel BDT derivative PBDTBPS–BDD with both acceptors C71BM and ITIC. The optimized polymer solar cells showed a PCE of 8.40% and 9.76% for both solar cells, respectively.
First measurement of the cross-correlation between CMB weak lensing and X-ray emission
Authors: Hurier G. , Singh P. , Hernández-Monteagudo C.
Published: April 2019

Since the publication of the results of thePlancksatellite mission in 2013, the local and early Universes have been considered to be in tension in respect of the determination of amplitude of the matter density spatial fluctuations (σ8) and the amount of matter present in the Universe (Ωm). This tension can be seen as a lack of massive galaxy clusters in the local Universe compared to the prediction inferred fromPlanckcosmic microwave background (CMB) best-fitting cosmology. In the present analysis we perform the first detection of the cross-correlation between X-rays and CMB weak lensing at 9.1σ. We next combine thermal Sunyaev–Zel’dovich effect, X-rays, and weak-lensing angular auto- and cross-correlation power spectra to determine the galaxy cluster hydrostatic mass bias. We derive (1 − bH) = 0.71 ± 0.07. Considering these constraints, we observe that estimations ofσ8in the local Universe are consistent withPlanckCMB best-fitting cosmology. However, these results are in clear tension with the output of hydrodynamical simulations that favor (1 − bH)> 0.8.
Grids of stellar models with rotation
Authors: Groh J. H. , Ekström S. , Georgy C. , Meynet G. , Choplin A. , Eggenberger P. , Hirschi R. , Maeder A. , Murphy L. J. , Boian I. , Farrell E. J.
Published: April 2019

The effects of rotation on stellar evolution are particularly important at low metallicity, when mass loss by stellar winds diminishes and the surface enrichment due to rotational mixing becomes relatively more pronounced than at high metallicities. Here we investigate the impact of rotation and metallicity on stellar evolution. Using similar physics as in our previous large grids of models at Z = 0.002 and Z = 0.014, we compute stellar evolution models with the Geneva code for rotating and nonrotating stars with initial masses (Mini) between 1.7 and 120 M⊙ and Z = 0.0004 (1/35 solar). This is comparable to the metallicities of the most metal poor galaxies observed so far, such as I Zw 18. Concerning massive stars, both rotating and nonrotating models spend most of their core-helium burning phase with an effective temperature higher than 8000 K. Stars become red supergiants only at the end of their lifetimes, and few red supergiants are expected. Our models predict very few to no classical Wolf–Rayet stars as a results of weak stellar winds at low metallicity. The most massive stars end their lifetimes as luminous blue supergiants or luminous blue variables, a feature that is not predicted by models with higher initial metallicities. Interestingly, due to the behavior of the intermediate convective zone, the mass domain of stars producing pair-instability supernovae is smaller at Z = 0.0004 than at Z = 0.002. We find that during the main sequence (MS) phase, the ratio between nitrogen and carbon abundances (N/C) remains unchanged for nonrotating models. However, N/C increases by factors of 10–20 in rotating models at the end of the MS. Cepheids coming from stars with Mini >  4 − 6 M⊙ are beyond the core helium burning phase and spend little time in the instability strip. Since they would evolve towards cooler effective temperatures, these Cepheids should show an increase of the pulsation period as a function of age.
Herschel-HOBYS study of the earliest phases of high-mass star formation in NGC 6357
Authors: Russeil D. , Figueira M. , Zavagno A. , Motte F. , Schneider N. , Men’shchikov A. , Bontemps S. , André P. , Anderson L. D. , Benedettini M. , Didelon P. , Di Francesco J. , Elia D. , Könyves V. , Nguyen Luong Q. , Nony T. , Pezzuto S. , Rygl K. L. J. , Schisano E. , Spinoglio L. , Tigé J. , White G. J.
Published: April 2019

Aims.To constrain models of high-mass star formation it is important to identify the massive dense cores (MDCs) that are able to form high-mass star(s). This is one of the purposes of theHerschel/HOBYS key programme. Here, we carry out the census and characterise of the properties of the MDCs population of the NGC 6357 H IIregion.

Methods.Our study is based on theHerschel/PACS and SPIRE 70−500 μm images of NGC 6357 complemented with (sub-)millimetre and mid-infrared data. We followed the procedure established by theHerschel/HOBYS consortium to extract ~0.1 pc massive dense cores using thegetsourcessoftware. We estimated their physical parameters (temperatures, masses, luminosities) from spectral energy distribution (SED) fitting.

Results.We obtain a complete census of 23 massive dense cores, amongst which one is found to be IR-quiet and twelve are starless, representing very early stages of the star-formation process. Focussing on the starless MDCs, we have considered their evolutionary status, and suggest that only five of them are likely to form a high-mass star.

Conclusions.We find that, contrarily to the case in NGC 6334, the NGC 6357 region does not exhibit any ridge or hub features that are believed to be crucial to the massive star formation process. This study adds support for an empirical model in which massive dense cores and protostars simultaneously accrete mass from the surrounding filaments. In addition, the massive star formation in NGC 6357 seems to have stopped and the hottest stars in Pismis 24 have disrupted the filaments.
VLT/FLAMES high-resolution chemical abundances in Sculptor: a textbook dwarf spheroidal galaxy
Authors: Hill V. , Skúladóttir Á. , Tolstoy E. , Venn K. A. , Shetrone M. D. , Jablonka P. , Primas F. , Battaglia G. , de Boer T. J. L. , François P. , Helmi A. , Kaufer A. , Letarte B. , Starkenburg E. , Spite M.
Published: April 2019

We present detailed chemical abundances for 99 red-giant branch stars in the centre of the Sculptor dwarf spheroidal galaxy, which have been obtained from high-resolution VLT/FLAMES spectroscopy. The abundances of Li, Na, α-elements (O, Mg, Si, Ca Ti), iron-peak elements (Sc, Cr, Fe, Co, Ni, Zn), and r- and s-process elements (Ba, La, Nd, Eu) were all derived using stellar atmosphere models and semi-automated analysis techniques. The iron abundances populate the whole metallicity distribution of the galaxy with the exception of the very low metallicity tail, −2.3 ≤ [Fe/H] ≤ −0.9. There is a marked decrease in [α/Fe] over our sample, from the Galactic halo plateau value at low [Fe/H] and then, after a “knee”, a decrease to sub-solar [α/Fe] at high [Fe/H]. This is consistent with products of core-collapse supernovae dominating at early times, followed by the onset of supernovae type Ia as early as ∼12 Gyr ago. The s-process products from low-mass AGB stars also participate in the chemical evolution of Sculptor on a timescale comparable to that of supernovae type Ia. However, the r-process is consistent with having no time delay relative to core-collapse supernovae, at least at the later stages of the chemical evolution in Sculptor. Using the simple and well-behaved chemical evolution of Sculptor, we further derive empirical constraints on the relative importance of massive stars and supernovae type Ia to the nucleosynthesis of individual iron-peak and α-elements. The most important contribution of supernovae type Ia is to the iron-peak elements: Fe, Cr, and Mn. There is, however, also a modest but non-negligible contribution to both the heavier α-elements: S, Ca and Ti, and some of the iron-peak elements: Sc and Co. We see only a very small or no contribution to O, Mg, Ni, and Zn from supernovae type Ia in Sculptor. The observed chemical abundances in Sculptor show no evidence of a significantly different initial mass function, compared to that of the Milky Way. With the exception of neutron-capture elements at low [Fe/H], the scatter around mean trends in Sculptor for [Fe/H] >  −2.3 is extremely low, and compatible with observational errors. Combined with the small scatter in the age-elemental abundances relation, this calls for an efficient mixing of metals in the gas in the centre of Sculptor since ∼12 Gyr ago.
Characterisation of the Perseid meteoroid stream through SPOSH observations between 2010–2016
Authors: Margonis A. , Christou A. , Oberst J.
Published: April 2019

We have characterised the Perseid meteoroid stream from data acquired in a series of observing campaigns between 2010 and 2016. The data presented in this work were obtained by the Smart Panoramic Optical Sensor Head (SPOSH), an all-sky camera system designed to image faint transient noctilucent phenomena on dark planetary hemispheres. For the data reduction, a sophisticated software package was developed that utilises the high geometric and photometric quality of images obtained by the camera system. We identify 934 meteors as Perseids, observed over a long period between late July (~124°) and mid-to-late August (~147°). The maximum meteor activity contributing to the annual shower was found at λ⊙ = 140°.08 ± 0°.07. The radiant of the shower was estimated at RA = 47°.2 and Dec = 57°.5 with a median error of 0°.6 and 0°.2, respectively. The mean population index of the shower between solar longitudes of 120°.68 and 145°.19 was r = 2.36 ± 0.05, showing strong temporal variation. A predicted outburst in shower activity for the night of August 11–12, 2016 was confirmed, with a peak observed 12.75 hr before the annual maximum at 23:30 ± 15′ UT. We measure a peak flux of 6.1 × 10−4 km−2 hr−1 for meteoroids of mass 1.6 × 10−2 g or more, appearing in the time period between 23:00 and 00:00 UT. We estimate the measured flux of the outburst meteoroids to be approximately twice as high as the annual meteoroid flux of the same mass. The population index of r = 2.19 ± 0.08, computed from the outburst Perseids in 2016, is higher than the value of r = 1.92 ± 0.06 derived from meteors observed in 2015 belonging to the annual Perseid shower which was active near the time of the outburst. A dust trail with an unusually high population index of r = 3.58 ± 0.24 was encountered in 2013 between solar longitudes 136°.261 and 137°.442. The relatively high r-value implies an encounter with a dust trail rich in low-mass particles.
Climate of an ultra hot Jupiter
Authors: Arcangeli Jacob , Désert Jean-Michel , Parmentier Vivien , Stevenson Kevin B. , Bean Jacob L. , Line Michael R. , Kreidberg Laura , Fortney Jonathan J. , Showman Adam P.
Published: April 2019

We present the analysis of a full-orbit, spectroscopic phase curve of the ultra hot Jupiter (UHJ) WASP-18b, obtained with the Wide Field Camera 3 aboard the Hubble Space Telescope. We measured the normalised day-night contrast of the planet as >0.96 in luminosity: the disc-integrated dayside emission from the planet is at 964 ± 25 ppm, corresponding to 2894 ± 30 K, and we place an upper limit on the nightside emission of <32 ppm or 1430 K at the 3σ level. We also find that the peak of the phase curve exhibits a small, but significant offset in brightness of 4.5 ± 0.5° eastward. We compare the extracted phase curve and phase-resolved spectra to 3D global circulation models and find that broadly the data can be well reproduced by some of these models. We find from this comparison several constraints on the atmospheric properties of the planet. Firstly we find that we need efficient drag to explain the very inefficient day-night recirculation observed. We demonstrate that this drag could be due to Lorentz-force drag by a magnetic field as weak as 10 gauss. Secondly, we show that a high metallicity is not required to match the large day-night temperature contrast. In fact, the effect of metallicity on the phase curve is different from cooler gas-giant counterparts because of the high-temperature chemistry in the atmosphere of WASP-18b. Additionally, we compared the current UHJ spectroscopic phase curves, WASP-18b and WASP-103b, and show that these two planets provide a consistent picture with remarkable similarities in their measured and inferred properties. However, key differences in these properties, such as their brightness offsets and radius anomalies, suggest that UHJ could be used to separate between competing theories for the inflation of gas-giant planets.
Gaia-assisted selection of a quasar reddened by dust in an extremely strong damped Lyman-α absorber at z = 2.226
Authors: Geier S. J. , Heintz K. E. , Fynbo J. P. U. , Ledoux C. , Christensen L. , Jakobsson P. , Krogager J.-K. , Milvang-Jensen B. , Møller P. , Noterdaeme P.
Published: April 2019

Damped Lyman-α absorbers (DLAs) as a class of quasi-stellar object (QSO) absorption-line systems are currently our most important source of detailed information on the cosmic chemical evolution of galaxies. However, the degree to which this information is biased by dust remains to be understood. One strategy is to specifically search for QSOs that are reddened by metal-rich and dusty foreground absorbers. In this Letter, we present the discovery of a z = 2.60 QSO that is strongly reddened by dust in an intervening extremely strong DLA at z = 2.226. This QSO was identified through a novel selection that combined the astrometric measurements from ESA’s Gaia satellite with extisting optical and near- to mid-infrared photometry. We infer a total neutral atomic-hydrogen column density of log N(H I) = 21.95 ± 0.15 and a lower limit on the gas-phase metallicity of [Zn/H] >  −0.96. This DLA is also remarkable in that it exhibits shielded neutral gas that is visible in C I, and it shows tentative detections of CO molecular bands. The spectral energy distribution of the QSO is well accounted for by a spectral energy distribution that is normal for a QSO and is reddened by dust from a DLA with 10% solar metallicity, a dust extinction of AV = 0.82 ± 0.02 mag, and an extinction curve that resembles that of the Large Magellanic Cloud, including the characteristic 2175 Å extinction feature. Such QSO absorption-line systems have been shown to be very rare in previous surveys, which have mostly revealed sight-lines with low extinction. The present case therefore suggests that previous samples have under-represented the fraction of dusty absorbers. Building a complete sample of such systems is required to assess the significance of this effect.
Dust production scenarios in galaxies at z ∼6–8.3
Authors: Leśniewska Aleksandra , Michałowski Michał Jerzy
Published: April 2019

Context. The mechanism of dust formation in galaxies at high redshift is still unknown. Asymptotic giant branch (AGB) stars and explosions of supernovae (SNe) are possible dust producers, and non-stellar processes may substantially contribute to dust production, for example grain growth in the interstellar medium.

Aims. Our aim is to determine the contribution to dust production of AGB stars and SNe in nine galaxies at z ∼ 6−8.3, for which observations of dust have been recently attempted.

Methods. In order to determine the origin of the observed dust we have determined dust yields per AGB star and SN required to explain the total amounts of dust in these galaxies.

Results. We find that AGB stars were not able to produce the amounts of dust observed in the galaxies in our sample. In order to explain these dust masses, SNe would have to have maximum efficiency and not destroy the dust which they formed.

Conclusions. Therefore, the observed amounts of dust in the galaxies in the early universe were formed either by efficient supernovae or by a non-stellar mechanism, for instance the grain growth in the interstellar medium.