bluuebunny/crossref_metadata_2025 huggingface dataset:
Intra-cluster GC-LMXB in the Fornax galaxy cluster
Authors: Riccio G. , Paolillo M. , D’Abrusco R. , Cantiello M. , Jin X. , Li Z. , Venhola A. , D’Ago G. , Puzia Thomas H. , Iodice E. , Pota V. , Napolitano N. , Hilker M. , Mieske S. , Spavone M. , Peletier R. , Eigenthaler P.
Published: March 2020

The formation of Low mass X-ray binaries (LMXB) is favored within dense stellar systems such as Globular Clusters (GCs). The connection between LMXB and Globular Clusters has been extensively studied in the literature, but these studies have always been restricted to the innermost regions of galaxies. We present a study of LMXB in GCs within the central 1.5 deg2 of the Fornax cluster with the aim of confirming the existence of a population of LMXB in intra-cluster GCs and understand if their properties are related to the host GCs, to the environment or/and to different formation channels.
A deep view into the nucleus of the Sagittarius dwarf spheroidal galaxy: M54
Authors: Alfaro-Cuello M. , Kacharov N. , Neumayer N. , Mastrobuono-Battisti A. , Lützgendorf N. , Seth Anil C. , Böker T. , Kamann S. , Leaman R. , van de Ven G. , Bianchini P. , Watkins L. L. , Lyubenova M.
Published: March 2020

Nuclear star clusters hosted by dwarf galaxies exhibit similar characteristics to high-mass, metal complex globular clusters. This type of globular clusters could, therefore, be former nuclei from accreted galaxies. M54 resides in the photometric center of the Sagittarius dwarf galaxy, at a distance where resolving stars is possible. M54 offers the opportunity to study a nucleus before the stripping of their host by the tidal field effects of the Milky Way. We use a MUSE data set to perform a detailed analysis of over 6600 stars. We characterize the stars by metallicity, age, and kinematics, identifying the presence of three stellar populations: a young metal-rich (YMR), an intermediate-age metal-rich (IMR), and an old metal-poor (OMP). The evidence suggests that the OMP population is the result of accretion of globular clusters in the center of the host, while the YMR population was born in-situ in the center of the OMP population.
The contribution of Globular Clusters to the stellar halo using APOGEE and GAIA
Authors: Horta Danny , Ted Mackereth J. , Schiavon Ricardo P. ,   SDSS-IV/APOGEE Collaboration
Published: March 2020

Over the last decade, much of the key questions in Galactic Archaeology have been asnwered by studying the Milky Way’s globular cluster (GC) system. Following on this, it has been shown that a substantial fraction of the Milky Way’s stellar halo field arises from GC dissolution. In this work, we make use of the latest data release fromn the APOGEE survey to study GC dissolution ratios in different spatial regions of the Galaxy. Our results will allow us to constrain many astrophysical questions, such as: the origin of N-Rich stars, the mass contribution from GCs to the stellar halo of the Galaxy, the origin of the Galactic GC system and the mass assembly of the Milky Way.
X-ray sources in Galactic globular clusters and old open clusters
Authors: van den Berg Maureen
Published: March 2020

The features and make up of the population of X-ray sources in Galactic star clusters reflect the properties of the underlying stellar environment. Cluster age, mass, stellar encounter rate, binary frequency, metallicity, and maybe other properties as well, determine to what extent we can expect a contribution to the cluster X-ray emission from low-mass X-ray binaries, millisecond pulsars, cataclysmic variables, and magnetically active binaries. Sensitive X-ray observations withXMM-Newton and certainlyChandra have yielded new insights into the nature of individual sources and the effects of dynamical encounters. They have also provided a new perspective on the collective X-ray properties of clusters, in which the X-ray emissivities of globular clusters and old open clusters can be compared to each other and to those of other environments. I will review our current understanding of cluster X-ray sources, focusing on star clusters older than about 1 Gyr, illustrated with recent results.
Self‐Consistent Ice Mass Balance and Regional Sea Level From Time‐Variable Gravity
Authors: Sutterley Tyler C. , Velicogna Isabella , Hsu Chia‐Wei
Published: March 2020

Measurements of time‐variable gravity from the Gravity Recovery and Climate Experiment (GRACE) and the GRACE Follow‐on (GRACE‐FO) missions are an invaluable tool for monitoring changes in the mass of the Earth's glaciated regions. We improve upon estimates of glacier and ice sheet mass balance from time‐variable gravity by including instantaneous spatiotemporal variations in sea level. Here, a least squares mascon technique is combined with solutions to the sea level equation to iteratively correct the GRACE/GRACE‐FO data for the induced sea level response on a monthly basis. We find that variations in regional sea level affect ice sheet mass balance estimates in Greenland by approximately 4% and in Antarctic by approximately 5%. Since 2002, the Greenland ice sheet has been losing mass at an average rate of 263 ± 23 Gt/yr, and the Antarctic ice sheet has been losing mass at average rates between 90 ± 52 and 122 ± 53 Gt/yr depending on the rate of glacial isostatic adjustment. The mass losses from both ice sheets represent an increase of 15.6 ± 2.0 mm to global mean sea levels since 2002.
Global K‐Pg Layer Deposited From a Dust Cloud
Authors: Artemieva Natalia , Morgan Joanna
Published: March 2020

Although it is widely agreed that the distal K‐Pg clay layer contains ejecta from the Chicxulub impact site, no current models can explain how these ejecta travel from the impact site around the globe. A widely accepted hypothesis is that impact spherules and shocked minerals in the layer were ejected from an expanding impact plume and traveled to their final destination on a ballistic path. Shocked minerals, however, are ejected at too low a velocity to reach distal sites, and plausible ballistic ejection models cannot explain the observed ejecta distribution. Using a suite of numerical simulations, we find that intense interactions between the ejecta curtain and atmosphere generate a fast‐moving dust cloud traveling at speeds of a few kilometers per second, which carries a substantial fraction of ejecta, including shocked minerals, to distal sites. We conclude that ejecta curtain material must make a major contribution to the formation of the distal K‐Pg layer.
Comparing the Properties of ICME‐Induced Forbush Decreases at Earth and Mars
Authors: Freiherr von Forstner Johan L. , Guo Jingnan , Wimmer‐Schweingruber Robert F. , Dumbović Mateja , Janvier Miho , Démoulin Pascal , Veronig Astrid , Temmer Manuela , Papaioannou Athanasios , Dasso Sergio , Hassler Donald M. , Zeitlin Cary J.
Published: March 2020

Forbush decreases (FDs), which are short‐term drops in the flux of galactic cosmic rays, are caused by the shielding from strong and/or turbulent magnetic structures in the solar wind, especially interplanetary coronal mass ejections (ICMEs) and their associated shocks, as well as corotating interaction regions. Such events can be observed at Earth, for example, using neutron monitors, and also at many other locations in the solar system, such as on the surface of Mars with the Radiation Assessment Detector instrument onboard Mars Science Laboratory. They are often used as a proxy for detecting the arrival of ICMEs or corotating interaction regions, especially when sufficient in situ solar wind measurements are not available. We compare the properties of FDs observed at Earth and Mars, focusing on events produced by ICMEs. We find that FDs at both locations show a correlation between their total amplitude and the maximum hourly decrease, but with different proportionality factors. We explain this difference using theoretical modeling approaches and suggest that it is related to the size increase of ICMEs, and in particular their sheath regions, en route from Earth to Mars. From the FD data, we can derive the sheath broadening factor to be between about 1.5 and 1.9, agreeing with our theoretical considerations. This factor is also in line with previous measurements of the sheath evolution closer to the Sun.
Sea Surface Kinetic Energy as a Proxy for Phytoplankton Light Limitation in the Summer Pelagic Southern Ocean
Authors: Gradone J. C. , Oliver M. J. , Davies A. R. , Moffat C. , Irwin A.
Published: March 2020

The pelagic Southern Ocean is a high‐nutrient, low‐chlorophyll ecosystem. Here, phytoplankton growth is colimited by iron supply and light availability. This creates a general expectation that when light is available in the austral summer (shallow mixing depths), phytoplankton concentrations may be high or low depending on the delivery of iron to the surface layer. When light is not adequate (deep mixing depths), phytoplankton concentrations will likely be low, even if iron is available. Here we show that low surface kinetic energy behaves like a necessary but not sufficient condition for high chlorophyll concentrations. In high kinetic energy conditions, high chlorophyll concentrations are rare. Conversely, under low kinetic energy conditions, both high and low chlorophyll concentrations were observed. We show that higher kinetic energy conditions are related to deeper mixed layers, which is likely a proxy for local light conditions. Probabilistic models of chlorophyll based on surface kinetic energy were able to describe 30% of the spatial variability in monthly chlorophyll climatologies. This means that local light availability, proxied by mixing through kinetic energy, significantly shapes the spatial distribution of chlorophyll in the Southern Ocean. We suggest that regions with consistently higher kinetic energy may not be as sensitive to iron inputs compared to historic iron addition experiments, which were conducted in low surface kinetic energy conditions.
Dynamical Downscaling of CO2 in 2016 Over the Contiguous United States Using WRF‐VPRM, a Weather‐Biosphere‐Online‐Coupled Model
Authors: Hu Xiao‐Ming , Crowell Sean , Wang Qingyu , Zhang Yao , Davis Kenneth J. , Xue Ming , Xiao Xiangming , Moore Berrien , Wu Xiaocui , Choi Yonghoon , DiGangi Joshua P.
Published: March 2020

Ecosystem function (particularly CO2 fluxes and the subsequent atmospheric transport), synoptic‐scale weather (e.g., midlatitude cyclones), and interactions between ecosystems and the atmosphere can be investigated using a weather‐biosphere‐online‐coupled model. The Vegetation Photosynthesis and Respiration Model (VPRM) was coupled with the Weather Research and Forecasting (WRF) model in 2008 to simulate “weather‐aware” biospheric CO2 fluxes and subsequent transport and dispersion. The ability of the coupled WRF‐VPRM modeling system to simulate the CO2 structures within midlatitude cyclones, however, has not been evaluated due to the lack of data within these weather systems. In this study, VPRM parameters previously calibrated off‐line using eddy covariance tower data over North America are implemented into WRF‐VPRM. The updated WRF‐VPRM is then used to simulate spatiotemporal variations of CO2 over the contiguous United States at a horizontal grid spacing of 12 km for 2016 using an optimized downscaling configuration. The downscaled fields are evaluated using remotely sensed data from the Orbiting Carbon Observatory‐2, Total Carbon Column Observing Network, and in situ aircraft measurements from Atmospheric Carbon and Transport‐America missions. Evaluations show that WRF‐VPRM captures the monthly variation of column‐averaged CO2 concentrations (XCO2) and episodic variations associated with frontal passages. The downscaling also successfully captures the horizontal CO2 gradients across fronts and vertical CO2 contrast between the boundary layer and the free troposphere. WRF‐VPRM modeling results indicate that from May to September, biogenic fluxes dominate variability in XCO2 over most of the contiguous United States, except over a few metropolitan areas such as Los Angeles.
APOEε4 potentiates the relationship between amyloid-β and tau pathologies
Authors: Therriault Joseph , Benedet Andrea L. , Pascoal Tharick A. , Mathotaarachchi Sulantha , Savard Melissa , Chamoun Mira , Thomas Emilie , Kang Min Su , Lussier Firoza , Tissot Cecile , Soucy Jean-Paul , Massarweh Gassan , Rej Soham , Saha-Chaudhuri Paramita , Poirier Judes , Gauthier Serge , Rosa-Neto Pedro ,   for the Alzheimer’s Disease Neuroimaging Initiative
Published: March 2020

APOEε4 is the most well-established genetic risk factor for sporadic Alzheimer’s disease and is associated with cerebral amyloid-β. However, the association between APOEε4 and tau pathology, the other major proteinopathy of Alzheimer’s disease, has been controversial. Here, we sought to determine whether the relationship between APOEε4 and tau pathology is determined by local interactions with amyloid-β. We examined three independent samples of cognitively unimpaired, mild cognitive impairment and Alzheimer’s disease subjects: (1) 211 participants who underwent tau-PET with [18F]MK6240 and amyloid-PET with [18F]AZD4694, (2) 264 individuals who underwent tau-PET with [18F]Flortaucipir and amyloid-PET with [18F]Florbetapir and (3) 487 individuals who underwent lumbar puncture and amyloid-PET with [18F]Florbetapir. Using a novel analytical framework, we applied voxel-wise regression models to assess the interactive effect of APOEε4 and amyloid-β on tau load, independently of age and clinical diagnosis. We found that the interaction effect between APOEε4 and amyloid-β, rather than the sum of their independent effects, was related to increased tau load in Alzheimer’s disease-vulnerable regions. The interaction between one APOEε4 allele and amyloid-β was related to increased tau load, while the interaction between amyloid-β and two APOEε4 alleles was related to a more widespread pattern of tau aggregation. Our results contribute to an emerging framework in which the elevated risk of developing dementia conferred by APOEε4 genotype involves mechanisms associated with both amyloid-β and tau aggregation. These results may have implications for future disease-modifying therapeutic trials targeting amyloid or tau pathologies.
CDK4/6 inhibition blocks cancer metastasis through a USP51-ZEB1-dependent deubiquitination mechanism
Authors: Zhang Zhen , Li Jianjun , Ou Yang , Yang Guang , Deng Kaiyuan , Wang Qiong , Wang Zhaoyang , Wang Wenhao , Zhang Quansheng , Wang Hang , Sun Wei , Sun Peiqing , Yang Shuang
Published: March 2020

Tumor metastasis is the most common cause of cancer-related deaths, yet it remains poorly understood. The transcription factor zinc-finger E-box binding homeobox 1 (ZEB1) is involved in the epithelial-to-mesenchymal transition (EMT) and plays a pivotal role in tumor metastasis. However, the underlying mechanisms of the posttranslational modification of ZEB1 remain largely unknown. Herein, we demonstrated that specific inhibition of CDK4/6 was able to block tumor metastasis of breast cancer by destabilizing the ZEB1 protein in vitro and in vivo. Mechanistically, we determined that the deubiquitinase USP51 is a bona fide target of CDK4/6. The phosphorylation and activation of USP51 by CDK4/6 is necessary to deubiquitinate and stabilize ZEB1. Moreover, we found a strong positive correlation between the expression of p-RB (an indicator of CDK4/6 activity), p-USP51 and ZEB1 in metastatic human breast cancer samples. Notably, the high expression of p-RB, p-USP51, and ZEB1 was significantly correlated with a poor clinical outcome. Taken together, our results provide evidence that the CDK4/6-USP51-ZEB1 axis plays a key role in breast cancer metastasis and could be a viable therapeutic target for the treatment of advanced human cancers.
Non-inferiority randomised phase 3 trial comparing two radiation schedules (single vs. five fractions) in malignant spinal cord compression
Authors: Thirion Pierre G. , Dunne Mary T. , Kelly Paul J. , Flavin Aileen , O’Sullivan Joe M. , Hacking Dayle , Sasiadek Wojciech , Small Cormac , Pomeroy Maeve M. , Martin Joseph , McArdle Orla , Parker Imelda , O’Sullivan Lydia S. , Shannon Aoife M. , Clayton-Lea Angela , Collins Conor D. , Stevenson Michael R. , Alvarez-Iglesias Alberto , Armstrong John G. , Moriarty Michael
Published: March 2020

Background

The optimal EBRT schedule for MSCC is undetermined. Our aim was to determine whether a single fraction (SF) was non-inferior to five daily fractions (5Fx), for functional motor outcome.

Methods

Patients not proceeding with surgical decompression in this multicentre non-inferiority, Phase 3 trial were randomised to 10 Gy/SF or 20 Gy/5Fx. A change in mobility from baseline to 5 weeks for each patient, was evaluated by a Modified Tomita score: 1 = ‘Walk unaided’, 2 = ‘With walking aid’ and 3 = ‘Bed-bound’. The margin used to establish non-inferiority was a detrimental change of −0.4 in the mean difference between arms.

Results

One-hundred and twelve eligible patients were enrolled. Seventy-three patients aged 30–87 were evaluated for the primary analysis. The 95% CI for the difference in the mean change in mobility scores between arms was −0.12 to 0.6. Since −0.4 is not included in the interval, there is evidence that 10 Gy/SF is non-inferior to 20 Gy/5Fx. One grade 3 AE was reported in the 5Fx arm. Twelve (26%) patients in the 5Fx arm had a Grade 2–3 AE compared with six (11%) patients in the SF arm (p = 0.093).

Conclusion

For mobility preservation, one 10-Gy fraction is non-inferior to 20 Gy in five fractions, in patients with MSCC not proceeding with surgical decompression.

Clinical Trial Registration

Cancer Trials Ireland ICORG 05-03; NCT00968643; EU-20952.
An integrated analysis of lymphocytic reaction, tumour molecular characteristics and patient survival in colorectal cancer
Authors: Haruki Koichiro , Kosumi Keisuke , Li Peilong , Arima Kota , Väyrynen Juha P. , Lau Mai Chan , Twombly Tyler S. , Hamada Tsuyoshi , Glickman Jonathan N. , Fujiyoshi Kenji , Chen Yang , Du Chunxia , Guo Chunguang , Väyrynen Sara A. , Dias Costa Andressa , Song Mingyang , Chan Andrew T. , Meyerhardt Jeffrey A. , Nishihara Reiko , Fuchs Charles S. , Liu Li , Zhang Xuehong , Wu Kana , Giannakis Marios , Nowak Jonathan A. , Ogino Shuji
Published: March 2020

Background

Histological lymphocytic reaction is regarded as an independent prognostic marker in colorectal cancer. Considering the lack of adequate statistical power, adjustment for selection bias and comprehensive tumour molecular data in most previous studies, we investigated the strengths of the prognostic associations of lymphocytic reaction in colorectal carcinoma by utilising an integrative database of two prospective cohort studies.

Methods

We examined Crohn’s-like reaction, intratumoural periglandular reaction, peritumoural reaction and tumour-infiltrating lymphocytes in 1465 colorectal carcinoma cases. Using covariate data of 4420 colorectal cancer cases in total, inverse probability-weighted Cox proportional hazard regression model was used to control for selection bias (due to tissue availability) and potential confounders, including stage, MSI status, LINE-1 methylation, PTGS2 and CTNNB1 expression, KRAS, BRAF and PIK3CA mutations, and tumour neoantigen load.

Results

Higher levels of each lymphocytic reaction component were associated with better colorectal cancer-specific survival (Ptrend < 0.002). Compared with cases with negative/low intratumoural periglandular reaction, multivariable-adjusted HRs were 0.55 (95% CI, 0.42–0.71) in cases with intermediate reaction and 0.20 (95% CI, 0.12–0.35) in cases with high reaction. These relationships were consistent in strata of MSI status or neoantigen loads (Pinteraction > 0.2).

Conclusions

The four lymphocytic reaction components are prognostic biomarkers in colorectal carcinoma.
UBB pseudogene 4 encodes functional ubiquitin variants
Authors: Dubois Marie-Line , Meller Anna , Samandi Sondos , Brunelle Mylène , Frion Julie , Brunet Marie A. , Toupin Amanda , Beaudoin Maxime C. , Jacques Jean-François , Lévesque Dominique , Scott Michelle S. , Lavigne Pierre , Roucou Xavier , Boisvert François-Michel
Published: March 2020

Pseudogenes are mutated copies of protein-coding genes that cannot be translated into proteins, but a small subset of pseudogenes has been detected at the protein level. Although ubiquitin pseudogenes represent one of the most abundant pseudogene families in many organisms, little is known about their expression and signaling potential. By re-analyzing public RNA-sequencing and proteomics datasets, we here provide evidence for the expression of several ubiquitin pseudogenes including UBB pseudogene 4 (UBBP4), which encodes UbKEKS (Q2K, K33E, Q49K, N60S). The functional consequences of UbKEKS conjugation appear to differ from canonical ubiquitylation. Quantitative proteomics shows that UbKEKS modifies specific proteins including lamins. Knockout of UBBP4 results in slower cell division, and accumulation of lamin A within the nucleolus. Our work suggests that a subset of proteins reported as ubiquitin targets may instead be modified by ubiquitin variants that are the products of wrongly annotated pseudogenes and induce different functional effects.
An open data infrastructure for the study of anthropogenic hazards linked to georesource exploitation
Authors: Orlecka-Sikora Beata , Lasocki Stanisław , Kocot Joanna , Szepieniec Tomasz , Grasso Jean Robert , Garcia-Aristizabal Alexander , Schaming Marc , Urban Paweł , Jones Glenda , Stimpson Ian , Dineva Savka , Sałek Piotr , Leptokaropoulos Konstantinos , Lizurek Grzegorz , Olszewska Dorota , Schmittbuhl Jean , Kwiatek Grzegorz , Blanke Aglaja , Saccorotti Gilberto , Chodzińska Karolina , Rudziński Łukasz , Dobrzycka Izabela , Mutke Grzegorz , Barański Adam , Pierzyna Aleksandra , Kozlovskaya Elena , Nevalainen Jouni , Kinscher Jannes , Sileny Jan , Sterzel Mariusz , Cielesta Szymon , Fischer Tomas
Published: March 2020

Mining, water-reservoir impoundment, underground gas storage, geothermal energy exploitation and hydrocarbon extraction have the potential to cause rock deformation and earthquakes, which may be hazardous for people, infrastructure and the environment. Restricted access to data constitutes a barrier to assessing and mitigating the associated hazards. Thematic Core Service Anthropogenic Hazards (TCS AH) of the European Plate Observing System (EPOS) provides a novel e-research infrastructure. The core of this infrastructure, the IS-EPOS Platform (tcs.ah-epos.eu) connected to international data storage nodes offers open access to large grouped datasets (here termed episodes), comprising geoscientific and associated data from industrial activity along with a large set of embedded applications for their efficient data processing, analysis and visualization. The novel team-working features of the IS-EPOS Platform facilitate collaborative and interdisciplinary scientific research, public understanding of science, citizen science applications, knowledge dissemination, data-informed policy-making and the teaching of anthropogenic hazards related to georesource exploitation. TCS AH is one of 10 thematic core services forming EPOS, a solid earth science European Research Infrastructure Consortium (ERIC) (www.epos-ip.org).
Inner Mongolian Cashmere Goat Secondary Follicle Development Regulation Research Based on mRNA-miRNA Co-analysis
Authors: Han Wenjing , Yang Feng , Wu Zhihong , Guo Fuqiang , Zhang Junjie , Hai Erhan , Shang Fangzheng , Su Rui , Wang Ruijun , Wang Zhiying , Liu Zhihong , Zhao Yanhong , Wang Zhixin , Zhang Yanjun , Li Jinquan
Published: March 2020

Inner Mongolia cashmere goats, as an important part of animal husbandry production, play an important role in animal fiber industry. In recent years, scientific research has made a lot of explorations on the molecular regulation mechanism of hair follicle cycle growth, but few studies have been reported on the development of cashmere hair in fetal period. This study was based on the completion of 21 skin samples of mRNA and miRNA sequencing in 7 fetal periods (45 days, 55 days,65 days,75 days,95 days,115 days and 135 days) of the Inner Mongolia Cashmere goat. The target genes of miRNA associated with the development of secondary hair follicles in the cashmere goats were selected through the combination analysis of mRNA and miRNA data. Then the overexpression vector was constructed and the interaction between the miRNA and the target gene was identified by Dual-Luciferase Reporter Gene System. The function and interaction relationship of chi-miR-199a-5p and TGF-β2 were verified by RT-qPCR and western blot at the level of the fibroblasts in Inner Mongolia Cashmere goat. It provides a theoretical basis for further study of miRNA and its target genes regulating the occurrence and development of skin hair follicles. As the result shows, the expression trends of 7 genes (BAMBI, SMAD1, LTBP1, PPP2R1B, ID4, BMP8B and PITX2) and 7 miRNA (chi-miR-17-5p, chi-miR-125b-3p, chi-miR-21-5p, chi-miR-143-5p and chi-miR-106b-5p) in the skin samples for the seven stages of the fetus were shown to be consistent with the sequencing results. the results of sequencing are reliable. The correlation coefficient of TGF-β2 and chi-miR-199a-5p in fetal 45d-135d expression is −0.84, showing a strong negative correlation, The target relationship was preliminarily judged. The results of double luciferase vector report showed that chi-miR-199a-5p significantly decreased the expression of luciferase in TGF-β2 3′UTR, It is determined that there is a reciprocal relationship between them at a specific time. We transfected chi-miR199a-5p-FAM mimics into fibroblasts cultured in vitro from Inner Mongolia cashmere goats. After transfection, the cells were harvested to extract total RNA and protein. The mRNA and protein expression levels of TGF-β2 in fibroblasts were detected by RT-qPCR and western blot. It was verified that chi-miR-199a-5p inhibited TGF-β2 expression at both mRNA and protein translation levels in fibroblasts. At the same time, it was again proved that the TGF-β2 gene is a target gene of chi-miR199a-5p.
Graphene-enhanced Raman scattering on single layer and bilayers of pristine and hydrogenated graphene
Authors: Valeš Václav , Drogowska-Horná Karolina , Guerra Valentino L. P. , Kalbáč Martin
Published: March 2020

Graphene-enhanced Raman scattering (GERS) on isotopically labelled bilayer and a single layer of pristine and partially hydrogenated graphene has been studied. The hydrogenated graphene sample showed a change in relative intensities of Raman bands of Rhodamine 6 G (R6G) with different vibrational energies deposited on a single layer and bilayer graphene. The change corresponds qualitatively to different doping of graphene in both areas. Pristine graphene sample exhibited no difference in doping nor relative intensities of R6G Raman peaks in the single layer and bilayer areas. Therefore, it was concluded that strain and strain inhomogeneities do not affect the GERS. Because of analyzing relative intensities of selected peaks of the R6G probe molecules, it is possible to obtain these results without determining the enhancement factor and without assuming homogeneous coverage of the molecules. Furthermore, we tested the approach on copper phtalocyanine molecules.
Synechocystis sp. PCC 6803 overexpressing genes involved in CBB cycle and free fatty acid cycling enhances the significant levels of intracellular lipids and secreted free fatty acids
Authors: Eungrasamee Kamonchanock , Incharoensakdi Aran , Lindblad Peter , Jantaro Saowarath
Published: March 2020

The integrative aspect on carbon fixation and lipid production is firstly implemented in cyanobacterium Synechocystis sp. PCC 6803 using metabolic engineering approach. Genes related to Calvin–Benson–Bassham (CBB) cycle including rbcLXS and glpD and free fatty acid recycling including aas encoding acyl-ACP synthetase were practically manipulated in single, double and triple overexpressions via single homologous recombination. The significantly increased growth rate and intracellular pigment contents were evident in glpD-overexpressing (OG) strain among all strains studied under normal growth condition. The triple aas_glpD_rbcLXS-overexpressing (OAGR) strain notably gave the highest contents of both intracellular lipids and extracellular free fatty acids (FFAs) of about 35.9 and 9.6% w/DCW, respectively, when compared to other strains at day 5 of cultivation. However, the highest intracellular lipid titer and production rate were observed in OA strain at day 5 (228.7 mg/L and 45.7 mg/L/day, respectively) and OG strain at day 10 (358.3 mg/L and 35.8 mg/L/day, respectively) due to their higher growth. For fatty acid (FA) compositions, the main saturated fatty acid of palmitic acid (C16:0) was dominantly found in both intracellular lipid and secreted FFAs fractions. Notably, intracellular FA proportion of myristic acid (C14:0) was induced in all engineered strains whereas the increase of stearic acid (C18:0) composition was found in extracellular FFAs fraction. Altogether, these overexpressing strains efficiently produced higher lipid production via homeostasis balance on both its lipid synthesis and FFAs secretion.
Diagnostic accuracy of intraoperative CT-imaging in complex articular fractures – a cadaveric study
Authors: Luxenhofer M. , Beisemann N. , Schnetzke M. , Vetter S. Y. , Grützner P. A. , Franke J. , Keil H.
Published: March 2020

Anatomic reconstruction of articular fractures is one of the critical factors in later achieving good functional outcome. Intraoperative 3D imaging has been shown to offer better evaluation and therefore can significantly improve the results. The purpose of this study was to assess the difference between intraoperative three-dimensional fluoroscopy (3D) and intraoperative computed tomography (iCT) imaging regarding fracture reduction, implant placement and articular impressions in a distal humeral fracture model. AO type 13-B2 fracture pattern were created in upper extremity cadaver specimens. Articular step-offs, intra-articular screw placement and intraarticular impressions of different degrees of severity were created. All specimens had imaging performed. For each articular pattern 3D fluoroscopy in standard (3Ds) and high quality (3Dh) were performed (Arcadis Orbic, Siemens, Germany) as well as an intraoperative CT scan (iCT, Airo, Brainlab, Germany). Three observers evaluated all imaging studies regarding subjective and objective parameters. iCT is more precise than 3D fluoroscopic imaging for detection of articular impressions. Articular step-offs and intraarticular screw placement are similar for iCT and 3D. Subjective imaging quality is the highest for iCT and lowest for 3Ds. Intraoperative CT may be particularly useful in assessing articular impressions and providing a good subjective image quality for the surgeon.
NBEAL1 controls SREBP2 processing and cholesterol metabolism and is a susceptibility locus for coronary artery disease
Authors: Bindesbøll Christian , Aas Aleksander , Ogmundsdottir Margret Helga , Pankiv Serhiy , Reine Trine , Zoncu Roberto , Simonsen Anne
Published: March 2020

Dysregulated cholesterol homeostasis promotes the pathology of atherosclerosis, myocardial infarction and strokes. Cellular cholesterol is mainly regulated at the transcriptional level by SREBP2, but also through uptake of extracellular cholesterol from low density lipoproteins (LDL) via expression of LDL receptors (LDLR) at the cell surface. Identification of the mechanisms involved in regulation of these processes are thus key to understand the pathology of coronary artery disease. Here, we identify the large and poorly characterized BEACH domain protein Neurobeachin-like (NBEAL) 1 as a Golgi- associated protein required for regulation of cholesterol metabolism. NBEAL1 is most abundantly expressed in arteries. Genetic variants in NBEAL1 are associated with decreased expression of NBEAL1 in arteries and increased risk of coronary artery disease in humans. We show that NBEAL1 regulates cholesterol metabolism by modulating LDLR expression in a mechanism involving interaction with SCAP and PAQR3 and subsequent SREBP2-processing. Thus, low expression of NBEAL1 may lead to increased risk of coronary artery disease by downregulation of LDLR levels.
Compositional heterogeneity confers selective advantage to model protocellular membranes during the origins of cellular life
Authors: Sarkar Susovan , Dagar Shikha , Verma Ajay , Rajamani Sudha
Published: March 2020

Protocellular membranes are thought to be composed of mixtures of single chain amphiphiles, such as fatty acids and their derivatives, moieties that would have been part of the complex prebiotic chemical landscape. The composition and physico-chemical properties of these prebiological membranes would have been significantly affected and regulated by their environment. In this study, pertinent properties were systematically characterized, under early Earth conditions. Two different fatty acids were mixed with their respective alcohol and/or glycerol monoester derivatives to generate combinations of binary and tertiary membrane systems. Their properties were then evaluated as a function of multiple factors including their stability under varying pH, varying Mg2+ ion concentrations, dilution regimes, and their permeability to calcein. Our results demonstrate how environmental constraints would have acted as important prebiotic selection pressures to shape the evolution of prebiological membranes. The study also illustrates that compositionally diverse membrane systems are more stable and robust to multiple selection pressures, thereby making them more suitable for supporting protocellular life.
The Impact of Microplastic Particles on Population Dynamics of Predator and Prey: Implication of the Lotka-Volterra Model
Authors: Huang Qi , Lin Yuyang , Zhong Qiyin , Ma Fei , Zhang Yixin
Published: March 2020

Microplastic particles are widely distributed in a variety of ecosystems and can be transferred to predators along a food chain after being ingested by prey. However, how microplastic particles affect prey and predator populations is not fully understood. In this study, using the Lotka-Volterra model, we theoretically investigated predator-prey population dynamics in terms of toxicological response intensity (strength to population growth rate) to microplastic particles, and examined the negative effects on prey feeding ability and predator performance due to microplastic particles. Results of numerical simulations indicate the critical properties of the predator-prey system in response to microplastic particles: (i) predators are more vulnerable than prey under exposure to microplastic particles; (ii) the effect of microplastic particles on prey and predator population growths can be negligible when toxicological response intensities of prey and predator are small; (iii) this system is prey dependent for predator functional response, whose stability highly relies on the density of prey; (iv) the reduced feeding capacity of prey and predator induced by microplastic particles does not significantly affect the population dynamics of the predator-prey system. Moreover, our analysis suggests that dynamic Lotka-Volterra models can play a vital role in predicting ecological impacts of microplastic particles on predator-prey population dynamics.
Chemical modification of melphalan as a key to improving treatment of haematological malignancies
Authors: Gajek Arkadiusz , Poczta Anastazja , Łukawska Małgorzata , Cecuda- Adamczewska Violetta , Tobiasz Joanna , Marczak Agnieszka
Published: March 2020

Chemical modification of known, effective drugs is one method to improve chemotherapy. Thus, the object of this study was to generate melphalan derivatives with improved cytotoxic activity in human cancer cells (RPMI8226, HL60 and THP1). Several melphalan derivatives were synthesised, modified in their two important functional groups. Nine analogues were tested, including melphalan compounds modified: only at the amino group, by replacing the amine with an amidine group containing a morpholine ring (MOR-MEL) or with an amidino group and dipropyl chain (DIPR-MEL); only at the carboxyl group to form methyl and ethyl esters of melphalan (EM-MEL, EE-MEL); and in a similar manner at both functional groups (EM-MOR-MEL, EE-MOR-MEL, EM-DIPR-MEL, EE-DIPR-MEL). Melphalan derivatives were evaluated for cytotoxicity (resazurin viability assay), genotoxicity (comet assay) and the ability to induce apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labelling, TUNEL, phosphatidylserine externalisation, chromatin condensation, activity of caspases 3/7, 8 and 9 and intracellular concentration of calcium ions) in comparison with the parent drug. Almost all derivatives, with the exception of MOR-MEL and DIPR-MEL, were found to be more toxic than melphalan in all cell lines evaluated. Treatment of cultures with the derivatives generated a significant higher level of DNA breaks compared to those treated with melphalan, especially after longer incubation times. In addition, all the melphalan derivatives demonstrated a high apoptosis-inducing ability in acute monocytic and promyelocytic leukemia cells. This study showed that the mechanism of action of the tested compounds differed depending on the cell line, and allowed the selection of the most active compounds for further, more detailed investigations.
Comparison of Quantitative light-induced fluorescence-digital (QLF-D) images and images of disclosed plaque for planimetric quantification of dental plaque in multibracket appliance patients
Authors: Klaus Katharina , Glanz Tabea , Glanz Alexander Georg , Ganss Carolina , Ruf Sabine
Published: March 2020

The purpose of the present cross-sectional clinical study was to check the ability of plaque detection and quantification by QLF-D against conventional digital photographs of disclosed plaque in multibracket appliance (MB) patients. 20 patients were included according to the following criteria: (1) upper and lower jaw treated by MB appliance, (2) patients being 16 years of age or older, (3) all central and lateral incisors as well as canines in situ, (4) absence of developmental defects, carious lesions, surface fillings, prosthetic restorations or recessions greater than 1/3 of root length in central/lateral incisors and canines as well as (5) declaration of consent. QLF-D and conventional photographs were analyzed planimetrically regarding plaque coverage on buccal and oral surfaces of central/lateral incisors and canines. The conventional photographs of stained plaque served as gold standard. On average, in QLF-D pictures 20.7% ± 17.4 of the tooth surfaces were covered with plaque, while the conventional photographs of disclosed plaque presented a mean plaque-covered area of 36.2% ± 23.5. The Bland-Altman plot for both imaging modalities showed a very large inconsistent scattering with both negative and positive deviations. The method discrepancy increased with increasing plaque coverage, thus indicating a systematic method error. On average, the deviation of the methods from the optimal line of accordance was −15.5%. In patients wearing MB appliances, there was no clinical significant agreement regarding the plaque-covered tooth surface depicted by QLF-D respectively conventional images of disclosed plaque. Due to the large method discrepancy, QLF-D is currently not reliable for precise plaque quantification in MB patients.
Enhanced selectivity, cellular uptake, and in vitro activity of an intrinsically fluorescent copper–tirapazamine nanocomplex for hypoxia targeted therapy in prostate cancer
Authors: Silva Vera L. , Kaassis Abdessamad , Dehsorkhi Ashkan , Koffi Cédrik-Roland , Severic Maja , Abdelhamid Moustafa , Nyimanu Duuamene , Morris Christopher J. , Al-Jamal Wafa’ T.
Published: March 2020

Cu(TPZ)2 complex as a promising hypoxia selective cytotoxin in prostate cancer.
Hybrid density functional studies of native defects and H impurities in wurtzite CdSe
Authors: Kong Bo , An Xin-You , Zeng Ti-Xian , Zhang Jihua
Published: March 2020

By using DFT methods, we have revealed that H impurities in CdSe could be the dominant and effective origin for the unintentional n-type conductivity.
Li-ion transport at the interface between a graphite anode and Li2CO3solid electrolyte interphase:ab initiomolecular dynamics study
Authors: Baba Takeshi , Sodeyama Keitaro , Kawamura Yoshiumi , Tateyama Yoshitaka
Published: March 2020

DFT calculation based free energy profile for Li-ion transport across graphite anode/Li2CO3SEI interface, indicating how to understand the profile change between discharging and charging in battery.
Multi-corneal barrier-on-a-chip to recapitulate eye blinking shear stress forces
Authors: Abdalkader Rodi , Kamei Ken-ichiro
Published: March 2020

Human corneal epithelium coexists with tear fluids and shows its barrier functionality under the dynamic conditions of eye blinking. We developed a microfluidic platform enabling the dynamic culture of the human corneal barrier with recapitulation of eye blinking.
A nano-integrated diagnostic and therapeutic platform with oxidation–reduction reactions in tumor microenvironments
Authors: Zhao Lei , Qiu Guihua , Wang Kai , Chen Hu , Ruan Fengkai , Liu Nan , Deng Zifeng , Yao Youliang , Guo Dongbei , Wang Dai , Sha Li , Kong Xiangyu , Liu Wenzhi , Zhang Yongxing
Published: March 2020

MHP responds to the TME, self-assembles to produce ultra-small nanoparticles (USNPs), increases penetration of the tumor stroma, and enhances chemoradiotherapy.
Chain extender effect of 3-(4-hydroxyphenyl)propionic acid/layered double hydroxide in biopolyesters containing the succinate moiety
Authors: Sisti Laura , Totaro Grazia , Celli Annamaria , Marek Adam A. , Verney Vincent , Leroux Fabrice
Published: March 2020

3-(4-Hydroxyphenyl)propionic acid intercalated in Mg2Al/layered double hydroxide has been used as a filler in biopolyesters containing the succinate moiety, with the aim of inducing a chain extender effect.
Pore formation induced by nanoparticles binding to a lipid membrane
Authors: Pang Yui Tik , Ge Zhenpeng , Zhang Bokai , Xiu Peng , Li Quan , Wang Yi
Published: March 2020

A nanoparticle needs to be both sharp and large enough in order to spontaneously pierce a membrane.
Geometry-tailored freestanding epitaxial Pd, AuPd, and Au nanoplates driven by surface interactions
Authors: Yoo Youngdong , Kim Si-in , Kim Jihwan , Kim Bongsoo
Published: March 2020

Freestanding epitaxial Pd, AuPd, and Au nanoplates with tunable geometry are synthesized in the vapor phase.
Chemical transformations of push–pull fluorenones: push–pull dibenzodicyanofulvenes as well as fluorenone– and dibenzodicyanofulvene–tetracyanobutadiene conjugates
Authors: Kato Shin-ichiro , Kijima Tomokazu , Shiota Yoshihito , Abe Tsukasa , Kuwako Satoshi , Miyauchi Hidenori , Yoshikawa Naoki , Yamamoto Koji , Yoshizawa Kazunari , Yoshihara Toshitada , Tobita Seiji , Nakamura Yosuke
Published: March 2020

We report push–pull fluorenones (FOs) that can be transformed into dibenzodicyanofulvenes (DBDCFs). These FOs and DBDCFs, which contain a CC bond, can subsequently be converted into tetracyanobutadiene conjugates.
Nisin/polyanion layer-by-layer films exhibiting different mechanisms in antimicrobial efficacy
Authors: Fael Hanan , Demirel A. Levent
Published: March 2020

Polyanion–nisin multilayer films exhibit antimicrobial activity by controlled release of nisin or as stable biofilm inhibiting coatings depending on polyanion.
Verification of sortase for protein conjugation by single-molecule force spectroscopy and molecular dynamics simulations
Authors: Tian Fang , Li Guoqiang , Zheng Bin , Liu Yutong , Shi Shengchao , Deng Yibing , Zheng Peng
Published: March 2020

SMFS and MD simulations revealed a closed conformation and a decreased stability of sortase-mediated polyprotein I27 when a linker with a high content of glycine is used.
Ferracyclic carbonyl complexes as anti-inflammatory agents
Authors: Wright Mark A. , Wooldridge Tyler , O’Connell Maria A. , Wright Joseph A.
Published: March 2020

Reaction of Fe(CO)4Br2 with 2-aminopyridine and 2-aminonapthalene yields ferracyclic iron(ii) complexes bearing two CO ligands. These release CO in the light, but suppress inflammation only in the dark.
PROTAC-mediated degradation of class I histone deacetylase enzymes in corepressor complexes
Authors: Smalley Joshua P. , Adams Grace E. , Millard Christopher J. , Song Yun , Norris James K. S. , Schwabe John W. R. , Cowley Shaun Michael , Hodgkinson James T.
Published: March 2020

We have identified a proteolysis targeting chimera (PROTAC) of class I HDACs 1, 2 and 3. Our PROTAC decreased HDAC 1, 2 & 3 protein abundance, increased histone acetylation levels and compromised colon cancer HCT116 cell viability.
Effect of stepwise protonation of an N-containing ligand on the formation of metal–organic salts and coordination complexes in the solid state
Authors: Lv Haidong , Li Haitao , Xin Lianxin , Guo Fang
Published: March 2020

Controlled synthesis of a series of metal–organic salts and coordination complexes is tuned by the protonation of ligand, and their transformations are induced by the solid–gas and concentration of [H+].
980 nm NIR light driven overall water splitting over a combined CdS–RGO–NaYF4–Yb3+/Er3+ photocatalyst
Authors: Gao Wei , Wu Yuqi , Lu Gongxuan
Published: March 2020

Infrared light (NIR) accounts for more than 50% of the energy donated by the Sun to the Earth, but most of this type of energy is not utilized in photocatalytic reactions.
[Bmmim]6[In10Se16Cl4]·(MIm)2: an organic-ligand free discrete T3 cluster for efficient hydrogen evolution under visible light irradiation
Authors: Wang Yanqi , Hu Qianqian , Jin Jiance , Li Jilong , Li Jianrong , Huang Xiaoying
Published: March 2020

An organic-ligand free selenide T3 cluster exhibits a much higher photocatalytic hydrogen evolution activity after being stably dispersed in a solvent (6.5 times) than that in the solid state.
Research progress on solutions to the sneak path issue in memristor crossbar arrays
Authors: Shi Lingyun , Zheng Guohao , Tian Bobo , Dkhil Brahim , Duan Chungang
Published: March 2020

This review timely surveyed recent progress on solutions to the sneak path issue in memristor crossbar arrays.
Confined synthesis of carbon dots with tunable long-wavelength emission in a 2-dimensional layered double hydroxide matrix
Authors: Liu Wendi , Liang Ruizheng , Lin Yanjun
Published: March 2020

CDs with gradual modulation in structures and optical properties can be obtained through a confined reaction in 2-dimentsonal layered double hydroxides.
Synthesis of substituted naphtho[1,2-b]benzofuran-7(8H)-ones via photoinduced rearrangement of 4H-chromen-4-one derivatives
Authors: Lichitskii Boris V. , Melekhina Valeriya G. , Komogortsev Andrey N. , Milyutin Constantine V. , Fakhrutdinov Artem N. , Gorbunov Yury O. , Krayushkin Michail M.
Published: March 2020

A simple and efficient method was developed for the synthesis of substituted naphtho[1,2-b]benzofuran-7(8H)-ones based on the photorearrangement reaction of 4H-chromen-4-one derivatives.
Palladium(ii)-catalyzed stereoselective synthesis of C-glycosides from glycals with diaryliodonium salts
Authors: Pal Kumar Bhaskar , Lee Jiande , Das Mrinmoy , Liu Xue-Wei
Published: March 2020

An effective Pd(ii)-catalyzed stereoselective C-glycosylation method has been successfully manifested for the synthesis of diversely functionalized 2,3-dideoxy C-aryl glycosides starting from glycals with a wide range of diaryliodonium salts.
Cyclo-oligomerization of hydroxyl-containing mono-functional benzoxazines: a mechanism for oligomer formation
Authors: Zhen Hecheng , Yang Huiyun , Wang Mei , Lu Guosheng , Liu Yanfang , Run Mingtao
Published: March 2020

The oligomerization of mono-functional benzoxazines is demonstrated with intermolecular cyclization via a Mannich bridge structure as the primary reaction pathway.
Highly ordered supramolecular structure built from poly(4-(4-vinylphenylpyridine)) and 1,1′-ferrocenedicarboxylic acid via hydrogen bonding
Authors: Wen Zuwang , Kim Wonbin , Yoo Seung Jo , Chae Chang-Geun , Seo Ho-Bin , Bak In-Gyu , Changez Mohammad , Lee Jae-Suk
Published: March 2020

A molecular-level ordered supramolecular nanostructure is formed of P4VPPy and FDA, using a solvent vapor thermal annealing process that initiates hydrogen bonding directed self-assembly.