bluuebunny/crossref_metadata_2025 huggingface dataset:
Update on Fluorescence In Situ Hybridization in Melanoma: State of the Art
Authors: Gerami Pedram , Zembowicz Artur
Published: February 2021

Context.—Recent advances in understanding the molecular basis of melanoma have resulted in development of fluorescence in situ hybridization (FISH) protocols designed to detect genetic abnormalities discriminating melanoma from nevi. The most extensively studied is a 4-probe multicolor FISH probe panel targeting chromosomes 6 and 11. Validation studies showed promising sensitivity and specificity for distinguishing benign nevi and malignant melanoma by FISH. Recent studies show that a melanoma FISH assay has great potential for becoming an important diagnostic adjunct in classification of melanocytic lesions and in diagnosis of melanoma.

Objective.—To present a comprehensive review of the science and practical aspects of FISH in melanoma for pathologists considering the use of melanoma FISH in their practice.

Data Sources.—Review of the literature and personal experience of the authors.

Conclusions.—Judicious use of a 4-probe multicolor melanoma FISH procedure can enhance accuracy for diagnosis of melanoma and improve classification of melanocytic proliferations.
BipA exerts temperature-dependent translational control of biofilm-associated colony morphology in Vibrio cholerae
Authors: del Peso Santos Teresa , Alvarez Laura , Sit Brandon , Irazoki Oihane , Blake Jonathon , Warner Benjamin R , Warr Alyson R , Bala Anju , Benes Vladimir , Waldor Matthew K , Fredrick Kurt , Cava Felipe
Published: February 2021

Adaptation to shifting temperatures is crucial for the survival of the bacterial pathogen Vibrio cholerae. Here, we show that colony rugosity, a biofilm-associated phenotype, is regulated by temperature in V. cholerae strains that naturally lack the master biofilm transcriptional regulator HapR. Using transposon-insertion mutagenesis, we found the V. cholerae ortholog of BipA, a conserved ribosome-associated GTPase, is critical for this temperature-dependent phenomenon. Proteomic analyses revealed that loss of BipA alters the synthesis of >300 proteins in V. cholerae at 22°C, increasing the production of biofilm-related proteins including the key transcriptional activators VpsR and VpsT, as well as proteins important for diverse cellular processes. At low temperatures, BipA protein levels increase and are required for optimal ribosome assembly in V. cholerae, suggesting that control of BipA abundance is a mechanism by which bacteria can remodel their proteomes. Our study reveals a remarkable new facet of V. cholerae’s complex biofilm regulatory network.
Linnaean natural history: An eighteenth-century ecology of knowledges
Authors: Burnett Linda Andersson
Published: February 2021

Keynote lecture at the conference "Nature and the Natural in the Eighteenth Century" organized by the Norwegian Society for Eighteenth-Century Studies, 3 February 2021.

RECORDED LECTURE: https://septentrio.uit.no/media/AnderssonBurnett_0.mp4

The lecture is in English. Abstract (in Norwegian): Linda Andersson Burnett leder et større forskningsprosjekt som tar for seg Carl von Linnés nettverk av korrespondenter og innsamlere som et eksempel på citizen science, eller «folkeforskning». Linné reiste selv omkring i riket og samlet observasjoner og artseksemplarer, mest berømt er hans Lappländska resa i 1732. Men som professor og anerkjent botaniker ble han mer og mer avhengig av bidrag fra samlere. Dels var det studenter, «linnélärjungar», som reiste rundt i hele verden. Dels var det lekfolk, lokale kontaktpersoner rundt omkring i det svenske riket. Hvem var disse lekfolkene, og hva var det slags natursyn som lå til grunn for deres samleraktivitet? Og ikke minst: Hvordan forholdt de seg til naturfolket lengst nord i det svenske riket, samene? Dette er spørsmål som Andersson Burnett vil belyse i sitt foredrag, «Linnaean natural history: An eighteenth-century ecology of knowledge».
COVID-19 incidence and mortality in Nigeria: gender based analysis
Authors: Olusola-Makinde Olubukola O. , Makinde Olusola S.
Published: February 2021

Background

Coronavirus Disease 2019 (COVID-19) has been surging globally. Risk strata in medical attention are of dynamic significance for apposite assessment and supply distribution. Presently, no known cultured contrivance is available to fill this gap of this pandemic. The aim of this study is to develop a predictive model based on vector autoregressive moving average (VARMA) model of various orders for gender based daily COVID-19 incidence in Nigeria. This study also aims to proffer empirical evidence that compares incidence between male and female for COVID-19 risk factors.

Methods

Wilcoxon signed-rank test is employed to investigate the significance of the difference in the gender distributions of the daily incidence. A VARMA model of various orders is formulated for the gender based daily COVID-19 incidence in Nigeria. The optimal VARMA model is identified using Bayesian information criterion. Also, a predictive model based on univariate autoregressive moving average model is formulated for the daily death cases in Nigeria. Fold change is estimated based on crude case-fatality risk to investigate whether there is massive underreporting and under-testing of COVID-19 cases in Nigeria.

Results

Daily incidence is higher in males on most days from 11 April 2020 to 12 September 2020. Result of Wilcoxon signed-rank test shows that incidence among male is significantly higher than female (p-value < 2.22 × 10−16). White neural network test shows that daily female incidence is not linear in mean (p-value = 0.00058746) while daily male incidence is linear in mean (p-value = 0.4257). McLeod-Li test shows that there is autoregressive conditional heteroscedasticity in the female incidence (Maximum p-value = 1.4277 × 10−5) and male incidence (Maximum p-value = 9.0816 × 10−14) at 5% level of significance. Ljung-Box test (Tsay, 2014) shows that the daily incidence cases are not random (p-value=0.0000). The optimal VARMA model for male and female daily incidence is VARMA (0,1). The optimal model for the Nigeria’s daily COVID-19 death cases is identified to be ARIMA (0,1,1). There is no evidence of massive underreporting and under-testing of COVID-19 cases in Nigeria.

Conclusions

Comparison of the observed incidence with fitted data by gender shows that the optimal VARMA and ARIMA models fit the data well. Findings highlight the significant roles of gender on daily COVID-19 incidence in Nigeria.
Effect of Alkylating Mutagens on Rooting Response and Callus Age on Shoot Regeneration of Rough Lemon (Citrus Jambhiri Lush.)
Authors: Iqbal Mudasir , Bakshi Parshant , Sinha B. K. , Iqbal Mohsin , Devi Arti
Published: February 2021

Many species of Citrus and compatible sexual relatives are being used to develop biotic and abiotic tolerant rootstocks and their ability to confer positive stionic effects. Citrus jambhiri is the commercial citrus rootstock in India, deep-rooted well adapted to the diverse agro-climatic conditions. It ensures high yield with large size fruits in most of the scion cultivars and at the same time is resistant to most of the viruses. For in vitro mutagenesis, leaf and epicotyl calli derived shoots were used as explant material. In-vitro mutagenesis is a valuable tool for improvement of a crop, especially when there is a need to add one or two easily identifiable characters in an otherwise well adapted variety, without disturbing its basic genotype. The alkylating agent methyl methane sulphonate (MMS) and ethyl methane sulphonate (EMS) at 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6%, were used for mutagenesis. The mutagenic calli derived shoots were regenerated on MS medium augmented with BAP (3.0 mg/l), followed by rooting in MS medium containing NAA (2.0 mg/l). Percent rooting (29.50-8.33%), (27.11-07.72%), number of roots per shoot (3.11-1.18), (3.12-1.04) and root length (4.13-2.22), (4.15-2.17) decreased with increasing doses of MMS and EMS treatments, respectively. Effect of increasing age of callus showed that callus retained regeneration capacity (3.55%) even after 210 days of culture by repeated sub-culturing. The plantlets were successfully acclimatized in different potting mixtures and highest survival rate (90.35%) was achieved in potting mixture containing garden soil with sand and farmyard manure (1:1:1).
Characterization and Classification of Soils of Harve-1 Microwatershed of Chamarajanagar District, Karnataka, India
Authors: Hegde Rajendra , Kumar M. B. Mahendra , Niranjana K. V. , Seema K. V. , Dhanorkar B. A.
Published: February 2021

Aims: The detailed survey of the microwatershed was carried out by using digitized cadastral map as a base. The objective of the investigation was undertaken to characterize and classify the soils of Harve-1 microwatershed of Chamarajanagar district, Karnataka.

Place and Duration of Study: soil survey was done and soil samples were collected from Harve-1 microwatershed of Chamarajanagar district in the year 2016. The laboratory characterization and soil classification work was done at National Bureau of soil survey and land use planning, Regional centre Hebbal, Bangalore, Karnataka.

Methodology: Using Cartosat-1 and LISS-IV merged satellite data at the scale of 1:7920 were used in conjunction with the cadastral map as a base. Soil profiles were exposed and location of soil profiles was recorded using GPS and studied from each landform for describing morphological characteristic as per the guidelines given in USDA soil survey manual (Soil Survey Staff 2014). Based on the soil-site characteristics, ten soil series were identified using the method employed by Reddy (2006). Horizon wise soil samples were collected, processed and analysed for various properties by adopting standard procedure.

Results: The study showed that, the soils were moderately shallow to moderately deep in depth. The colour of the soils varied from dark red to dark reddish brown. Texture of the soil varied from sandy loam to sandy clay loam in surface and sandy clay loam to sandy clay in subsurface. The structure was weak medium sub-angular blocky to moderate medium sub-angular blocky throughout the profile in all series. The consistency of majority of the soils were friable, slightly sticky and slightly plastic in surface and friable, moderately sticky and moderately plastic in subsurface. Soil reaction varied from slightly acidic to alkaline (5.70 to 8.18) in nature. Organic carbon content of the soils was low to high (0.20 to 1.24 per cent). Calcium and magnesium are dominant exchangeable cations followed by sodium and potassium. The CEC of the soils ranged from 3.17 to 25.76 cmol (p+) kg-1. Major proportion of soil series in the microwatershed belonged to the order of Alfisols (Paralitic Rhodustalfs, Typic Rhodustalfs, Typic Haplustalfs and Rhodic Paleustalfs) except Honnenahalli (HNH) series belong to the order of Inceptisols (Typic Haplustepts).

Conclusion: The soils of the microwatershed were comes under the order of alfisols and inceptisols. This generated information can help the researchers, farmers and planners to manage the natural resources for future planning and also to achieve sustainable productivity.
A 249‐yr chronosequence of forest plots from eight successive fires in the Eastern Canada boreal mixedwoods
Authors: Maleki Kobra , Marchand Philippe , Charron Danielle , Lafleur Benoit , Bergeron Yves
Published: February 2021

A combination of wildfires and defoliating insect outbreaks play an important role in the natural successional dynamics of North American boreal mixedwood forests, which, in the long term, change the post‐disturbance composition and structure of forest stands. After stand‐replacing disturbances (mainly wildfires), early successional hardwoods typically dominate the affected areas. Provided enough time following disturbances, the increasing recruitment of mid‐ to late‐successional softwoods as well as the mortality of hardwoods gradually change forest composition from hardwoods to admixtures of hardwood‐conifer species and conifer‐dominated stands in mid and late successional stages, respectively. Such mixedwoods are abundant across the southern Canadian boreal forest. In boreal Canada, mixedwoods are the most structurally heterogeneous forest ecosystems, are highly productive, and form an important source of timber supply. Here we present the EASTERN BOREAL MIXEDWOODS CANADA data set, which documents the changes in composition and structure of stands originating from eight different wildfires representing a chronosequence of 249 yr since fire in eastern Canada. This data set has been used in several different projects to study and model the influence of natural (e.g., insect outbreaks) and anthropogenic disturbances (e.g., harvesting) on the dynamics of post‐fire stands. The data set covers a high range of variability in stand composition and structure, explained by species establishment, dominance, and mixture. It thus constitutes a useful source of information to trace the dynamics of the main boreal tree species of eastern North America, from their establishment to their replacement at different spatial scales (e.g., from stand to landscape level). Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data. We are open to collaborate in developing or co‐authoring relevant research projects based on this data set.
South–north heterogeneity of the effect of volcanic eruptions on dryness/wetness in Central and Eastern China
Authors: Zheng Yuehan , Duan Jianping , Ma Zhuguo
Published: February 2021

Volcanic eruptions are an important driver for climate changes. However, the response of climate to volcanic eruptions sometimes varies from region to region. Although some studies reported that volcanic eruptions induced drought in Eastern China, the others argued that there is a possibility of wetter condition after volcanic eruptions in Eastern China. Until now, the response of dryness/wetness changes in this region to volcanic eruptions is controversial. Based on the dryness/wetness indexes from 100 sites in Central and Eastern China (CEC) over the past 500 years (1470–1999), the effects of volcanic eruptions occurred in the northern mid‐high latitudes (17 events) and the tropics (19 events) on dryness/wetness changes in CEC were analysed. Our results show that the significant response of dryness/wetness changes in CEC to volcanic eruptions occurred in the third or fourth year after the eruptions. Moreover, there is a significant north–south heterogeneity of the response of dryness/wetness changes in CEC to volcanic eruptions. Specifically, the response of dryness/wetness changes in northern CEC to volcanic eruptions is generally more sensitive than that in southern CEC. A persistent drying during the first to the fourth years post the volcanic events occurred in the northern mid‐high latitudes was found in north CEC, but not in south CEC. After the tropical volcanic events, there is a generally wetting in CEC, but it is stronger in north CEC than in south CEC. These results imply that, to some extent, volcanic eruptions occurred in the northern mid‐high latitudes may amplify dryness in north CEC, but may mitigate wetness in south CEC, while tropical volcanic eruptions may mitigate dryness in north CEC and amplify wetness in south CEC.
A confidence interval robust to publication bias for random‐effects meta‐analysis of few studies
Authors: Henmi Masayuki , Hattori Satoshi , Friede Tim
Published: February 2021

In meta‐analyses including only few studies, the estimation of the between‐study heterogeneity is challenging. Furthermore, the assessment of publication bias is difficult as standard methods such as visual inspection or formal hypothesis tests in funnel plots do not provide adequate guidance. Previously, Henmi and Copas (Statistics in Medicine 2010, 29: 2969–2983) proposed a confidence interval for the overall effect in random‐effects meta‐analysis that is robust to publication bias to some extent. As is evident from their simulations, the confidence intervals have improved coverage compared with standard methods. To our knowledge, the properties of their method have never been assessed for meta‐analyses including fewer than five studies. In this manuscript, we propose a variation of the method by Henmi and Copas employing an improved estimator of the between‐study heterogeneity, in particular when dealing with few studies only. In a simulation study, the proposed method is compared to several competitors. Overall, we found that our method outperforms the others in terms of coverage probabilities.
Optimization in treatment planning of high dose‐rate brachytherapy — Review and analysis of mathematical models
Authors: Morén Björn , Larsson Torbjörn , Tedgren Åsa Carlsson
Published: February 2021

Treatment planning in high dose‐rate brachytherapy has traditionally been conducted with manual forward planning, but inverse planning is today increasingly used in clinical practice. There is a large variety of proposed optimization models and algorithms to model and solve the treatment planning problem. Two major parts of inverse treatment planning for which mathematical optimization can be used are the decisions about catheter placement and dwell time distributions. Both these problems as well as integrated approaches are included in this review. The proposed models include linear penalty models, dose–volume models, mean‐tail dose models, quadratic penalty models, radiobiological models, and multiobjective models. The aim of this survey is twofold: (i) to give a broad overview over mathematical optimization models used for treatment planning of brachytherapy and (ii) to provide mathematical analyses and comparisons between models. New technologies for brachytherapy treatments and methods for treatment planning are also discussed. Of particular interest for future research is a thorough comparison between optimization models and algorithms on the same dataset, and clinical validation of proposed optimization approaches with respect to patient outcome.
Divergent ⇒ complex amplitudes in two dimensional string theory
Authors: Sen Ashoke
Published: February 2021

Abstract

In a recent paper, Balthazar, Rodriguez and Yin found remarkable agreement between the one instanton contribution to the scattering amplitudes of two dimensional string theory and those in the matrix model to the first subleading order. The comparison was carried out numerically by analytically continuing the external energies to imaginary values, since for real energies the string theory result diverges. We use insights from string field theory to give finite expressions for the string theory amplitudes for real energies. We also show analytically that the imaginary parts of the string theory amplitudes computed this way reproduce the full matrix model results for general scattering amplitudes involving multiple closed strings.
Self-dualities and renormalization dependence of the phase diagram in 3d O(N) vector models
Authors: Sberveglieri Giacomo , Serone Marco , Spada Gabriele
Published: February 2021

Abstract

In the classically unbroken phase, 3d O(N) symmetric ϕ4 vector models admit two equivalent descriptions connected by a strong-weak duality closely related to the one found by Chang and Magruder long ago. We determine the exact analytic renormalization dependence of the critical couplings in the weak and strong branches as a function of the renormalization scheme (parametrized by κ) and for any N. It is shown that for κ = κ∗ the two fixed points merge and then, for κ < κ∗, they move into the complex plane in complex conjugate pairs, making the phase transition no longer visible from the classically unbroken phase. Similar considerations apply in 2d for the N = 1 ϕ4 theory, where the role of classically broken and unbroken phases is inverted. We verify all these considerations by computing the perturbative series of the 3d O(N) models for the vacuum energy and for the mass gap up to order eight, and Borel resumming the series. In particular, we provide numerical evidence for the self-duality and verify that in renormalization schemes where the critical couplings are complex the theory is gapped. As a by-product of our analysis, we show how the non-perturbative mass gap at large N in 2d can be seen as the analytic continuation of the perturbative one in the classically unbroken phase.
A probabilistic atlas of the human ventral tegmental area (VTA) based on 7 Tesla MRI data
Authors: Trutti Anne C. , Fontanesi Laura , Mulder Martijn J. , Bazin Pierre-Louis , Hommel Bernhard , Forstmann Birte U.
Published: February 2021

Functional magnetic resonance imaging (fMRI) BOLD signal is commonly localized by using neuroanatomical atlases, which can also serve for region of interest analyses. Yet, the available MRI atlases have serious limitations when it comes to imaging subcortical structures: only 7% of the 455 subcortical nuclei are captured by current atlases. This highlights the general difficulty in mapping smaller nuclei deep in the brain, which can be addressed using ultra-high field 7 Tesla (T) MRI. The ventral tegmental area (VTA) is a subcortical structure that plays a pivotal role in reward processing, learning and memory. Despite the significant interest in this nucleus in cognitive neuroscience, there are currently no available, anatomically precise VTA atlases derived from 7 T MRI data that cover the full region of the VTA. Here, we first provide a protocol for multimodal VTA imaging and delineation. We then provide a data description of a probabilistic VTA atlas based on in vivo 7 T MRI data.
Blank thinning predictions of an aluminum alloy in hole expansion process using finite element method
Authors: Akşen Toros Arda , Firat Mehmet
Published: February 2021

The main objective of this study is to accurately predict the thinning behavior of AA6016-O aluminum alloy in the hole expansion test. In order to perform this aim, three yield functions, namely isotropic von Mises, quadratic Hill48 and non-quadratic Yld91, are considered and their prediction capabilities are evaluated in this study. Firstly, finite element (FE) model of hole expansion test is created by implicit FE software Marc, then FE simulations are performed with each yield criterion. In order to assess prediction capabilities of these yield criteria, thickness strain distributions along the three directions of the sheet (rolling, diagonal and transversal) and punch force–displacement curves are investigated. The results predicted from FE analyses are compared with experimental results. From the comparisons, it is observed that Yld91 yield criterion could successfully predict the thickness strain distributions along the rolling and transverse directions, whereas the other two criteria could only predict the thickness strain distributions along the diagonal direction. On the other hand, it is determined that punch force–displacement curves predicted from three models are identical and these predictions are overestimated compared to experimental data.
Bombs for Peace
Authors: Szamuely George
Published: February 2021

In the late 1990s NATO dropped bombs and supported armed insurgencies in Yugoslavia while insisting that its motives were purely humanitarian and that its only goal was peace. However, George Szamuely argues that NATO interventions actually prolonged conflicts, heightened enmity, increased casualties, and fueled demands for more interventions. Eschewing the one-sided approach adopted by previous works on the Yugoslavian crisis, Szamuely offers a broad overview of the conflict, its role in the rise of NATO's authority, and its influence on Western policy on the Balkans. His timely, judicious, and accessible study sheds new light on the roots of the contemporary doctrine of humanitarian intervention.
From Padi States to Commercial States
Authors: Bourdier Frédéric , Boutry Maxime , Ivanoff Jacques , Ferrari Olivier
Published: February 2021

"Zomia" is a term coined in 2002 to describe the broad swath of mountainous land in Southeast Asia that has always been beyond the reach of lowland governments despite their technical claims to control. This book expands the anthropological reach of that term, applying it to any deterritorialised people, from cast-out migrants to modern resisters-in the process finding new ways to understand the realities of peoples and ethnicities that refuse to become part of the modern state.
Viewing Disability in Medieval Spanish Texts
Authors: Scarborough Connie L.
Published: February 2021

This book is one of the first to examine medieval Spanish canonical works for their portrayals of disability in relationship to theological teachings, legal precepts, and medical knowledge. Connie L. Scarborough shows that physical impairments were seen differently through each lens. Theology at times taught that the disabled were 'marked by God,' their sins rendered on their bodies; at other times, they were viewed as important objects of Christian charity. The disabled often suffered legal restrictions, allowing them to be viewed with other distinctive groups, such as the ill or the poor. And from a medical point of view, a miraculous cure could be seen as evidence of divine intervention. This book explores all these perspectives through medieval Spain's miracle narratives, hagiographies, didactic tales, and epic poetry.
Modelscapes of Nationalism
Authors: Padan Yael
Published: February 2021

Modelscapes are clusters of miniature architectural models that represent entire environments. They're frequently found in museums as representations of heritage, architecture, and collective identity. This book offers a critical analysis of modelscapes, using case studies from Israel, to show how miniature representations of contested physical space participate in the construction of a sense of national identity and appropriation of the land and its history. What, Yael Padan asks, is the meaning of such models, and what role do they play within the context of an ongoing violent conflict over territory and history?
Turkey's 'Self' and 'Other' Definitions in the Course of the EU Accession Process
Authors: Saral Melek
Published: February 2021

While Turkey in recent years has experienced an exhaustive accession process to join the EU -a long desired aim-, at the same time it has been increasing its involvement across the Middle East, leading to a debate over whether it is altering its focus from West to East. This book reveals that a shift in focus can be seen through analysis of the Turkish political elites' definitions of "self" and "other" that were established as part of the EU accession process. Melek Saral uses these definitions to help us better understand the shift that Turkey is currently undergoing.
Motion correction for routine X-ray lung CT imaging
Authors: Kim Doil , Choi Jiyoung , Lee Duhgoon , Kim Hyesun , Jung Jiyoung , Cho Minkook , Lee Kyoung-Yong
Published: February 2021

A novel motion correction algorithm for X-ray lung CT imaging has been developed recently. It was designed to perform for routine chest or thorax CT scans without gating, namely axial or helical scans with pitch around 1.0. The algorithm makes use of two conjugate partial angle reconstruction images for motion estimation via non-rigid registration which is followed by a motion compensated reconstruction. Differently from other conventional approaches, no segmentation is adopted in motion estimation. This makes motion estimation of various fine lung structures possible. The aim of this study is to explore the performance of the proposed method in correcting the lung motion artifacts which arise even under routine CT scans with breath-hold. The artifacts are known to mimic various lung diseases, so it is of great interest to address the problem. For that purpose, a moving phantom experiment and clinical study (seven cases) were conducted. We selected the entropy and positivity as figure of merits to compare the reconstructed images before and after the motion correction. Results of both phantom and clinical studies showed a statistically significant improvement by the proposed method, namely up to 53.6% (p < 0.05) and up to 35.5% (p < 0.05) improvement by means of the positivity measure, respectively. Images of the proposed method show significantly reduced motion artifacts of various lung structures such as lung parenchyma, pulmonary vessels, and airways which are prominent in FBP images. Results of two exemplary cases also showed great potential of the proposed method in correcting motion artifacts of the aorta which is known to mimic aortic dissection. Compared to other approaches, the proposed method provides an excellent performance and a fully automatic workflow. In addition, it has a great potential to handle motions in wide range of organs such as lung structures and the aorta. We expect that this would pave a way toward innovations in chest and thorax CT imaging.
Non-adiabatic quantum interference in the ultracold Li + LiNa → Li2 + Na reaction
Authors: Kendrick Brian K. , Li Hui , Li Ming , Kotochigova Svetlana , Croft James F. E. , Balakrishnan Naduvalath
Published: February 2021

The outcome of the ultracold Li + LiNa reaction is governed by non-adiabatic quantum interference between the direct and looping pathways.
Ferromagnetic TM2BC (TM = Cr, Mn) monolayers for spintronic devices with high Curie temperature
Authors: Abdullahi Yusuf Zuntu , Vatansever Zeynep Demir , Ersan Fatih , Akinci Umit , Akturk Olcay Uzengi , Akturk Ethem
Published: February 2021

Transition metal boro-carbide (TM2BC) structures crystallize in the layered orthorhombic structure in their bulk phases.
Copper(ii) complex of N-truncated amyloid-β peptide bearing a His-2 motif as a potential receptor for phosphate anions
Authors: Tobolska Aleksandra , Wezynfeld Nina E. , Wawrzyniak Urszula E. , Bal Wojciech , Wróblewski Wojciech
Published: February 2021

Significant changes observed in the electrochemical response of the Cu(ii)-Aβ5–9complex upon phosphates addition provided a new insight into the design of a promising class of peptide-based molecular receptors selective for phosphate species.
Selectivity-tunable oxidation of tetrahydro-β-carboline over an OMS-2 composite catalyst: preparation and catalytic performance
Authors: Bi Xiuru , Tao Luyao , Yao Nan , Gou Mingxia , Chen Gexin , Meng Xu , Zhao Peiqing
Published: February 2021

A H3PO4·12WO3/OMS-2 nanocomposite catalyst doped with sodium phosphowolframate was prepared with MnSO4·H2O as Mn2+ precursor and remarkably enhanced catalytic activity and selectivity in aerobic oxidative dehydrogenation of tetrahydro-β-carboline.
Coordination of trivalent lanthanum and cerium, and tetravalent cerium and actinides (An = Th(iv), U(iv), Np(iv)) by a 4-phosphoryl 1H-pyrazol-5-olate ligand in solution and the solid state
Authors: Zhang Jianfeng , Wenzel Marco , Schnaars Kathleen , Hennersdorf Felix , Schwedtmann Kai , März Juliane , Rossberg André , Kaden Peter , Kraus Florian , Stumpf Thorsten , Weigand Jan J.
Published: February 2021

Single crystal X-ray analyses, solution NMR and EXAFS studies of a series of f-elements metal(iv) complexes of a 4-phosphoryl pyrazolone ligand show essentially the same coordination of the metal ions in solution and in the solid state.
High‐precision refocusing method with one interpolation for camera array images
Authors: Yang Jungang , Xiao Chao , Wang Yingqian , An Chengjin , An Wei
Published: February 2021

Camera array image refocusing can change the in‐focus region so that objects lying on a specified plane are in focus, whereas objects lying off this plane are blurred. Existing refocusing methods for camera array or light field images usually contain two interpolations. Since interpolation brings distortion, especially on the sharp edge in the images, existing methods are not sufficiently precise. In order to improve the quality of the refocusing result, the authors propose a high‐precision method to refocus camera array images. They first back‐project the pixel coordinates to a corresponding location on the focal plane in the world coordinate. Then they reproject the world coordinates to the pixel coordinates by using the parameters of each camera in the array. After that, they align the images with the focal plane by employing interpolation according to the acquired pixel coordinates. Finally, they get the synthetic image refocused on the focal plane by averaging the resulted images. In the proposed method, only one interpolation is used. So that it alleviates the quality degradation of the refocused image compared to the existing methods. Experiments on real‐world scenes (captured by their self‐developed light field devices) demonstrate that their method can yield better results than the existing methods.
CMCS‐net: image compressed sensing with convolutional measurement via DCNN
Authors: Xie Yahong , Wang Hailin , Wang Jianjun
Published: February 2021

Recently, deep learning methods have made a remarkable improvement in compressed sensing image recovery stage. In the compressed measurement stage, the existing methods measured by block by block owing to a huge measurement dictionary for the whole images and the high computational complexity. In this work, a novel deep convolutional neural network (DCNN) named Convolutional Measurement Compressed Sensing network (CMCS‐net) is proposed for image compressed sensing considering both convolutional measurement (CM) and sparse prior. Different from existing works, the convolution operation is adopted both in the measurement phase and reconstruction phase, which retains the structure information of images much better. Simultaneously, the size of the measurement matrix is no longer limited by data dimensions. Particularly, by unfolding the CM process to analyse a Toeplitz‐type matrix, the theoretical support of the convolutional compressed measurement is proposed. In addition, in the recovery phase, the authors consider the sparse prior in nature images by embedding the truncated hierarchical projection algorithm into their architecture to solve the problem of multilayered convolutional sparse coding. Furthermore, extensive experiments demonstrate that their proposed CMCS‐net can marvellously reconstruct the images and fully remove the block artefact.
Exploring HNC and HCN line emission as probes of the protoplanetary disk temperature
Authors: Long Feng , Bosman Arthur D. , Cazzoletti Paolo , van Dishoeck Ewine F. , Öberg Karin I. , Facchini Stefano , Tazzari Marco , Guzmán Viviana V. , Testi Leonardo
Published: February 2021

Context. The distributions and abundances of molecules in protoplanetary disks are powerful tracers of the physical and chemical disk structures. The abundance ratios of HCN and its isomer HNC are known to be sensitive to gas temperature. Their line ratios might therefore offer a unique opportunity to probe the properties of the emitting gas.

Aims. We investigate the HNC and HCN line emission in disks at (sub-)millimeter wavelengths and explore their potential utility for probing disk temperature and other disk properties.

Methods. Using the 2D thermochemical code DALI, we ran a set of disk models accounting for different stellar properties and radial and vertical disk structures, with an updated chemical network for the nitrogen chemistry. These modeling results were then compared with observations, including new observations obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) of HNC J = 3−2 for the TW Hya disk and HNC J = 1−0 for 29 disks in Lupus.

Results. Similar to CN, HCN and HNC have brighter line emission in models with larger disk flaring angles and higher UV fluxes. HNC and HCN are predicted to be abundant in the warm surface layer and outer midplane region, which results in ring-shaped emission patterns. However, the precise emitting regions and emission morphology depend on the probed transition, as well as on other parameters such as C and O abundances. The modeled HNC-to-HCN line intensity ratio increases from <0.1 in the inner disk to up to 0.8 in the outer disk regions, which can be explained by efficient HNC destruction at high temperatures. Disk-integrated HNC line fluxes from current scarce observations and its radial distribution in the TW Hya disk are broadly consistent with our model predictions.

Conclusions. The HNC-to-HCN flux ratio robustly increases with radius (decreasing temperature), but its use as a chemical thermometer in disks is affected by other factors, including UV flux and C and O abundances. High-spatial resolution ALMA disk observations of HNC and HCN that can locate the emitting layers would have the great potential to constrain both the disk thermal and UV radiation structures, and also to verify our understanding of the nitrogen chemistry.
Weak-lensing mass reconstruction using sparsity and a Gaussian random field
Authors: Starck J.-L. , Themelis K. E. , Jeffrey N. , Peel A. , Lanusse F.
Published: February 2021

Aims. We introduce a novel approach to reconstructing dark matter mass maps from weak gravitational lensing measurements. The cornerstone of the proposed method lies in a new modelling of the matter density field in the Universe as a mixture of two components: (1) a sparsity-based component that captures the non-Gaussian structure of the field, such as peaks or halos at different spatial scales, and (2) a Gaussian random field, which is known to represent the linear characteristics of the field well.

Methods. We propose an algorithm called MCALens that jointly estimates these two components. MCALens is based on an alternating minimisation incorporating both sparse recovery and a proximal iterative Wiener filtering.

Results. Experimental results on simulated data show that the proposed method exhibits improved estimation accuracy compared to customised mass-map reconstruction methods.
Star formation quenching stages of active and non-active galaxies
Authors: Kalinova V. , Colombo D. , Sánchez S. F. , Kodaira K. , García-Benito R. , González Delgado R. , Rosolowsky E. , Lacerda E. A. D.
Published: February 2021

The mechanisms that bring galaxies to strongly reduce their star formation activity (star-formation quenching) remain poorly understood. To better study galaxy evolution, we propose a classification based on maps of ionised hydrogen distribution traced by the kiloparsec-resolved, equivalent width of Hαmaps, and the nuclear activity of the galaxies using information from the Baldwin-Philips-Terlevich diagnostic diagrams. Using these tools, we group a sample of 238 galaxies from the Calar Alto Legacy Integral Field spectroscopy Area survey in six quenching stages (QSs): (i) objects dominated by recent star formation; (ii) systems that present a quiescent-nuclear-ring structure in their centre; (iii) galaxies that are centrally quiescent; (iv) galaxies with no clear pattern in their ionisation gas distribution (mixed); (v) systems that posses only a few star-forming regions (nearly retired), or (vi) galaxies that are completely quiescent (fully retired). Regarding their nuclear activity, we further divide the galaxies into two groups: active systems that host a weak or strong active galactic nucleus (AGN) at their centre, and non-active objects. Galaxies grouped into quenching-stage classes occupy specific locations on the star-formation-rate versus stellar mass diagram. The ‘blue cloud’ is populated by the star-forming and the quiescent-nuclear-ring galaxies, the ‘green valley’ is populated by centrally quiescent and mixed systems, and the ‘red sequence’ by the nearly- and fully retired objects. Generally, galaxies that host a weak or strong AGN show properties comparable to those of their non-active counterparts at the same QSs, except for the AGN-hosting star-forming systems. The degree of star-formation quenching increases along the present emission-line pattern sequence from star-forming to fully retired. The proposed emission-line classes reinforce the ‘inside-out’ quenching scenario, which foresees that the suppression of star formation begins from the central regions of the galaxies.
An observationally constrained model of strong magnetic reconnection in the solar chromosphere
Authors: Díaz Baso C. J. , de la Cruz Rodríguez J. , Leenaarts J.
Published: February 2021

Context.The evolution of the photospheric magnetic field plays a key role in the energy transport into the chromosphere and the corona. In active regions, newly emerging magnetic flux interacts with the pre-existent magnetic field, which can lead to reconnection events that convert magnetic energy into thermal energy.

Aims.We aim to study the heating caused by a strong reconnection event that was triggered by magnetic flux cancelation.

Methods.We use imaging and spectropolarimetric data in the Fe I6301& 6302 Å, Ca II8542 Å, and Ca IIK spectral lines obtained with the CRISP and CHROMIS instruments at the Swedish 1-m Solar Telescope. These data were inverted with the STiC code by performing multi-atom, multi-line, non-local thermodynamic equilibrium inversions. These inversions yielded a three-dimensional model of the reconnection event and surrounding atmosphere, including temperature, velocity, microturbulence, magnetic field, and radiative loss rate.

Results.The model atmosphere shows the emergence of magnetic loops with a size of several arcseconds into a pre-existing predominantly unipolar field. Where the reconnection region is expected to be, we see an increase in the chromospheric temperature of roughly 2000 K as well as bidirectional flows of the order of 10 km s−1emanating from there. We see bright blobs of roughly 0.2 arcsec in diameter in the Ca IIK, moving at a plane-of-the-sky velocity of the order of 100 km s−1and a blueshift of 100 km s−1, which we interpret as ejected plasmoids from the same region. This scenario is consistent with theoretical reconnection models, and therefore provides evidence of a reconnection event taking place. The chromospheric radiative losses at the reconnection site are as high as 160 kW m−2, providing a quantitative constraint on theoretical models that aim to simulate reconnection caused by flux emergence in the chromosphere.
Exploration archéologique de 170 hectares de plaine maritime (Bourbourg, Saint-Georges-sur-l’Aa, Craywick, Nord de la France) : restitution de la fermeture d’un estuaire au Moyen Âge et mise en évidence de mares endiguées
Authors: Deschodt Laurent , Lançon Mathieu , Desoutter Samuel , Hulin Guillaume , Simon François-Xavier , Vanwalscappel Bruno , Créteur Yves , Broes Frédéric , Devred Véronique , Favier Dominique , Le Bayon Anne-Lise
Published: February 2021

Dans le cadre de l’agrandissement du port de Dunkerque, plus de 170 hectares de la plaine maritime ont été explorés sur la future « Zone Grande Industrie », dans l’ancien estuaire de la Denna (ou Déna, ou L’Enna), sous-bassin du petite fleuve côtier Aa. Le diagnostic d’archéologie préventive classique par ouverture de tranchées a été accompagnée de recherches en archives, de prospections géophysiques, de levés géomorphologiques en sondages en puits (profonds de 3 m) et en coupes. L’intégration des études de nature différente permet d’aboutir à une compréhension du secteur meilleure que ne l’eût fait chaque discipline séparément. Les dépôts sont essentiellement des sables tidaux recoupés par des chenaux de marée. Les décimètres supérieurs sont parfois plus limoneux. Les mesures de conductivité apparente permettent de spatialiser les données lithostratigraphiques ponctuelles. Leur confrontation, ainsi que des indices venant du réseau parcellaire, permet la mise en évidence d’un bord ouest de l’estuaire, contemporain d’occupations humaines. De même, la confrontation des vestiges archéologiques levés lors du diagnostic avec une zonation basée sur la géophysique et la stratigraphie permet d’appréhender l’évolution du paysage, notamment l’expansion et la contraction de l’habitat du secteur, depuis les premières interventions aux environs des Xe–XIIe siècles sur la bordure ouest de l’estuaire. Depuis ce dernier, l’habitat a progressé vers le nord-est, jusqu’à un bras de la Denna resté longtemps actif et dont l’axe correspond au système de drainage actuel. La cartographie de conductivité électrique permet également de mettre en évidence des anomalies qui se sont révélées être de larges et profondes structures anthropiques (jusqu’à environ 40 m de diamètre et plus de 5 m de profondeur, soit −2,5 m sous la cote zéro). Bien que nombreuses, ces structures peuvent passer facilement inaperçues lors des diagnostics archéologiques. Plusieurs ont été testées. Leur remplissage est variable mais présente comme point commun une étanchéification du fond et des parois par des mottes d’argile. Ces structures sont interprétées comme des mares endiguées dont quelques exemples subsistent sur la côte de la mer du Nord (en Frise, en Zélande et en Allemagne). Elles permettaient de recueillir l’eau douce et leur couronne de remblais en élévation s’élevaient au-dessus des plus fortes marées.
Lubrication and shallow-water systems Bernis-Friedman and BD entropies
Authors: Bresch Didier , Colin Mathieu , Msheik Khawla , Noble Pascal , Song Xi
Published: February 2021

This paper concerns the results recently announced by the authors, in C.R. Acad. Sciences Maths volume 357, Issue 1, 1-6 (2019), which make the link between the BD entropy introduced by D. Bresch and B. Desjardins for the viscous shallow-water equations and the Bernis-Friedman (called BF in our paper) dissipative entropy introduced to study the lubrication equations. More precisely different dissipative BF entropies are obtained from the BD entropies playing with drag terms and capillarity formula for viscous shallow water type equations. This is the main idea in the paper which makes the link between two communities. The limit processes employ the standard compactness arguments taking care of the control in the drag terms. It allows in one dimension for instance to prove global existence of nonnegative weak solutions for lubrication equations starting from the global existence of nonnegative weak solutions for appropriate viscous shallow-water equations (for which we refer to appropriate references). It also allows to prove global existence of nonnegative weak solutions for fourth-order equation including the Derrida-Lebowitz-Speer-Spohn equation starting from compressible Navier-Stokes type equations.
Understanding the oblate shape of electron holes in magnetized plasmas
Authors: Ishimaru Matthew
Published: February 2021

Theoretical argument and particle in cell simulations show that gyrokinetic model cannot account for oblate plasma electron holes.
Capacity of Trolox to improve the development and quality of metabolically compromised bovine oocytes and embryos invitro during different windows of development
Authors: De Bie J. , Smits A. , Marei W. F. A. , Leroy J. L. M. R.
Published: February 2021

Trials to improve oocyte developmental competence under metabolic stress by using antioxidants may start before or after oocyte maturation. In the present conceptual study, we aimed to identify the most efficient timing of antioxidant application in relation to a metabolic insult using a bovine invitro embryo production model. Pathophysiological concentrations of palmitic acid (PA) were used to induce metabolic stress during oocyte maturation or embryo development. Trolox (TR; antioxidant) treatment prior to, during or after the PA insult was tested to evaluate the protective, neutralising and rescuing capacity of TR respectively. Changes in embryo developmental competence, mitochondrial activity, reactive oxygen species (ROS) concentrations, blastocyst cell allocation and apoptosis and cell stress-related gene expression were monitored. The improvement in developmental capacity was most obvious when oocytes were preloaded with TR before the PA insult. This protective effect could be explained by the observed combination of increased mitochondrial activity with reduced ROS production. This resulted in blastocysts with normal cell counts and apoptosis, as well as increased nuclear factor erythroid 2-related factor 2 (NRF2) expression (a marker for redox regulatory processes) and normalised the expression of the mitochondrial transcription factor A (TFAM), a marker of mitochondrial biogenesis. These results indicate that ‘pretreatment’ of oocytes with antioxidants produces embryos that seem to be more resilient to a metabolic stress insult.