bluuebunny/crossref_metadata_2025_split huggingface dataset:
Majority of cerebrospinal fluid‐contacting neurons in the spinal cord of C57Bl/6N mice is present in ectopic position unlike in other studied experimental mice strains and mammalian species
Authors: Tonelli Gombalová Zuzana , Košuth Ján , Alexovič Matiašová Anna , Zrubáková Jarmila , Žežula Ivan , Giallongo Toniella , Di Giulio Anna Maria , Carelli Stephana , Tomašková Lenka , Daxnerová Zuzana , Ševc Juraj 
Published: March 2020

AbstractCerebrospinal fluid contacting neurons (CSF‐cNs) represent a specific class of neurons located in close vicinity of brain ventricles and central canal. In contrast with knowledge gained from other vertebrate species, we found that vast majority of CSF‐cNs in the spinal cord of C57Bl/6N mice is located in ectopic distal ventral position. However, we found that small number of ectopic CSF‐cNs is present also in spinal cord of other investigated experimental mice strains (C57Bl/6J, Balb/C) and mammalian species (Wistar rats, New Zealand White rabbits). Similarly, as the proximal populations, ectopic CSF‐cNs retain PKD2L1‐immunoreactivity and synaptic contacts with other neurons. On the other side, they show rather multipolar morphology lacking thick dendrite contacting central canal lumen. Ectopic CSF‐cNs in the spinal cord of C57Bl/6N mice emerge during whole period devoted to production of CSF‐cNs and reach their ventral destinations during first postnatal weeks. In order to identify major gene, whose impairment could trigger translocation of CSF‐cNs outside the central canal area, we took advantage of close consanguinity of C57Bl/6J substrain with normal CSF‐cN distribution and C57Bl/6N substrain with majority of CSF‐cNs in ectopic position. Employing in silico analyses, we ranked polymorphisms in C57Bl/6N substrain and selected genes Crb1, Cyfip2, Adamts12, Plk1, and Herpud2 as the most probable candidates, whose product dysfunction might be responsible for the ectopic distribution of CSF‐cNs. Furthermore, segregation analysis of F2 progeny of parental C57Bl/6N and Balb/C mice revealed that polymorphic loci of Crb1 and Cyfip2 underlie the ectopic position of CSF‐cNs in the spinal cord of C57Bl/6N mice.
Optimization of porous stents for endovascular repair of abdominal aortic aneurysms
Authors: Stockle Juan , Romero David A. , Amon Cristina H. 
Published: March 2020

AbstractThis study presents a simulation‐based methodology to design porous stents to induce suitable hemodynamic environments inside abdominal aortic aneurysm (AAA) sacs. In the proposed methodology, an optimization algorithm iteratively modifies the porosity distribution of the stent and executes a computational fluid dynamics (CFD) simulation to determine the effect of these changes on the hemodynamic conditions inside the aneurysm sac. The optimization iterations proceed until relevant hemodynamic parameters are within ranges prescribed a priori by the user as desirable to control the progression of the AAA. The resulting porosity distribution uniquely describes the porous stent design that can control the hemodynamic environment (eg, shear stress at the aneurysm wall, pressure distribution, residence time), reducing AAA rupture risks and improving treatment efficacy. To demonstrate its potential, the proposed methodology is applied to idealized AAA geometry under steady‐state flow conditions, though it may be easily applied to more complex AAA geometries under transient, pulsatile flow conditions. The proposed methodology has the potential to enable the design of a new generation of porous stents tailored to patient‐specific geometries and flow conditions, to improve patient outcomes.
Topology hiding routing based on learning with errors
Authors: Wan Shaohua 
Published: March 2020

AbstractThe protocol of onion routing constitutes the underpinning of Onion Routing network for anonymous communication. However, since the main idea behind such protocol is to hierarchically peel the IP head and decode each crypted routing address, the topology with regards to path length or long‐term direction cannot be preserved. Owing to topology exposure, lots of attacks such as denial of service and differential flow analysis can be effectively conducted to violate the security of it. Moreover, considering that the path should be constructed by a sender in advance, onion routing is infeasible to be transplanted to ad hoc networks, let alone other defects such as heavy burden about computational complexity and package length. In this paper, a topology‐hiding routing protocol is proposed to address most of the aforementioned problems recurring to homomorphic learning with errors. Security analysis illustrated that nothing but only the IPs of adjacent hops will be revealed to any router. Also the computational complexity on sender side as well as the package length outperforms those of traditional onion routing algorithm in view of comparative simulation.
An Extensive Set of Accurate Fluoride Ion Affinities for p‐Block Element Lewis Acids and Basic Design Principles for Strong Fluoride Ion Acceptors
Authors: Erdmann Philipp , Leitner Jonas , Schwarz Julia , Greb Lutz 
Published: March 2020

AbstractThe computed fluoride ion affinity (FIA) is a valuable descriptor to assess the Lewis acidity of a compound. Despite its widespread use, the varying accuracy of applied computational models hampers the broad comparability of literature data. Herein, we evaluate the performance of selected methods (like DLPNO‐CCSD(T)) in FIA computations against CCSD(T)/CBS data and guide for the choice of suitable density functionals that allow the treatment of larger Lewis acids. Based on the benchmarked methods, we computed an extensive set of gas‐phase and solvation corrected FIA, that is covering group 13–16 elements featuring moderate to strong electron‐withdrawing substituents (190 entries). It permits an unbiased comparison of FIA over a significant fraction of the periodic table, serves as a source of reference for future synthetic or theoretical studies, and allows to derive some simple design principles for strong fluoride ion acceptors. Finally, the manuscript includes a tutorial section for the computation of FIA with and without the consideration of solvation.
Polydiacetylene–Perylenediimide Supercapacitors
Authors: De Adhikari Amrita , Morag Ahiud , Seo Joonsik , Kim Jong‐Man , Jelinek Raz 
Published: March 2020

AbstractOrganic supercapacitors have attracted interest as promising “green” and efficient components in energy storage applications. A polydiacetylene derivative coupled with reduced graphene oxide was employed, for the first time, to generate an organic pseudocapacitance‐based supercapacitor that exhibited excellent electrochemical properties. Specifically, diacetylene monomers were functionalized with perylenediimide (PDI), spontaneously forming elongated microfibers. Following polymerization through UV irradiation, the PDI–polydiacetylene microfibers were interspersed with reduced graphene oxide (rGO), generating a porous electrode material exhibiting a high surface area and facilitating efficient ion diffusion, both essential preconditions for supercapacitor applications. We show that PDI–polydiacetylene has an important role in enhancing the electrochemical properties as a supercapacitor electrode. Besides stabilizing the microporous electrode organization, the delocalized π electrons in both the PDI residues and conjugated network of the polydiacetylene contributed to a significantly higher capacitance (specific capacitance >600 F g−1 at 1 A g−1 current density), longer discharge time, and high power density. The PDI–polydiacetylene‐rGO electrodes were employed in a functional supercapacitor device.
High‐Loading Single‐Atom Copper Catalyst Supported on Coordinatively Unsaturated Al2O3 for Selective Synthesis of Homoallylboronates
Authors: Guo Tenglong , Tang Nanfang , Lin Feng , Shang Qinghao , Chen Shuai , Qi Haifeng , Pan Xiaoli , Wu Chuntian , Xu Guoliang , Zhang Jian , Xu Dezhu , Cong Yu 
Published: March 2020

AbstractSingle‐atom catalysts (SACs) as a bridge between hetero‐ and homogeneous catalysis have attracted much attention. However, it is still challenging to generate stable single atoms with high metal loadings, and the application of SACs in traditionally homogeneous catalytic reactions is highly desirable. Herein, a Cu SAC with a high Cu loading of 8.7 wt % supported on coordinatively unsaturated Al2O3 was prepared and used in the amine‐free synthesis of homoallylboranes. Up to 99 % conversion, 95 % 1,4‐selective boration of the enals, and 48–68 % isolated yields of homoallylboranes were achieved, equaling the results of reported homogenous catalysts, and the system was more efficient and stable than nano Cu/γ‐Al2O3. Mechanistic investigation indicated that Cu‐Bpin species are the active intermediates of selective boration. The superior catalytic and recycling performance of Cu SAC paves an efficient and green path toward selective synthesis of homoallyborane fine chemicals.
Evaluation of HER2 expression in urothelial carcinoma cells as a biomarker for circulating tumor cells
Authors: Nini Alessandro , Hoffmann Michèle Janine , Lampignano Rita , große Siemer Robert , van Dalum Guus , Szarvas Tibor , Cotarelo Cristina Lopez , Schulz Wolfgang Arthur , Niederacher Dieter , Neubauer Hans , Stoecklein Nikolas Hendrik , Niegisch Günter 
Published: March 2020

AbstractBackgroundDetection of circulating tumor cells (CTC) by techniques based on epithelial cell adhesion molecule (EpCAM) is suboptimal in urothelial carcinoma (UC). As HER2 is thought to be broadly expressed in UC, we explored its utility for CTC detection.MethodsHER2 and EpCAM expression was analyzed in 18 UC cell lines (UCCs) by qRT‐PCR, western blot and fluorescence‐activated cell scanning (FACS) and compared to the strongly HER2‐expressing breast cancer cell line SKBR3 and other controls. HER2 expression in UC patient tissues was measured by qRT PCR and correlated with data on survival and risk for metastasis. UCCs with high EpCAM and variable HER2 expression were used for spike‐in experiments in the CellSearch system. Twenty‐one blood samples from 13 metastatic UC patients were analyzed for HER2‐positive CTCs with CellSearch.ResultsHER2 mRNA and protein were broadly expressed in UCC, with some heterogeneity, but at least 10‐fold lower than in the HER‐2+ SKBR3 cells. Variations were unrelated to cellular phenotype or clinicopathological characteristics. EpCAM expression was essentially restricted to UCCs with epitheloid phenotypes. Heterogeneity of EpCAM and HER2 expression was observed also in spike‐in experiments. The 7 of 21 blood samples from 6 of 13 patients were enumerated as CTC positive via EpCAM, but only one sample stained weakly positive (1+) for HER2.ConclusionsDetection rate of CTCs by EpCAM in UC is poor, even in metastatic patients. Because of its widespread expression, particularly in patients with high risk of metastasis, detection of HER2 could improve identification of UC CTCs, which is why combined detection using antibodies for EpCAM and HER2 may be beneficial.
Flow cytometric analysis of fine needle aspirates is affected by tumor subtype, but not by anatomic location nor technique
Authors: Wake Laura M. , VandenBussche Christopher J. , Ali Syed Z. , Wagner‐Johnston Nina D. , Burns Kathleen H. , Gocke Christopher D. , Vuica‐Ross Milena , Borowitz Michael J. , Duffield Amy S. 
Published: March 2020

AbstractBackgroundCurrent clinical practices are shifting towards utilizing less invasive biopsy techniques, including fine needle aspiration (FNA) and needle core biopsies. If a patient has a suspected hematologic malignancy, a portion of the FNA sample is typically submitted for flow cytometry (FC) analysis, providing valuable immunophenotypic data.MethodsFNA specimens were identified via a pathology database search. All cases were morphologic evaluated and a subset of cases were analyzed by FC.Results245 hematologic FNA specimens were identified; 84% of these cases had an adequate number of cells for FC analysis, and an unequivocal morphologic diagnosis (benign or malignant) was rendered in 85%. The percentage of cases with an unequivocal diagnosis was statistically significantly higher in those with associated FC than with those without FC (90% vs 58%). Neither FNA technique nor anatomic site affected the likelihood of obtaining an adequate sample for FC analysis and/or rendering a definitive morphologic or unequivocal FC diagnosis. Likewise, tumor subtype did not affect the likelihood of acquiring enough cells for FC analysis, but occasionally resulted in equivocal FC diagnoses or discordant FNA and FC diagnoses. Aggressive B‐cell lymphomas and Hodgkin lymphomas were significantly less likely to be detected by FC as compared to low‐grade B‐cell lymphomas. Discrepancies between FNA and FC diagnoses occurred in 13% of cases. The majority of discrepancies (78%) included FC false negatives, while only 22% of cases had atypical or positive FC with negative FNA.ConclusionsFNA with associated FC is a powerful diagnostic technique; however, lymphoma subtype may affect diagnostic sensitivity by FC, and therefore, discordant FNA and FC results should be interpreted with caution.
Canadian polar bear population structure using genome‐wide markers
Authors: Jensen Evelyn L. , Tschritter Christina , de Groot Peter V. C. , Hayward Kristen M. , Branigan Marsha , Dyck Markus , Clemente‐Carvalho Rute B. G. , Lougheed Stephen C. 
Published: March 2020

AbstractPredicting the consequences of environmental changes, including human‐mediated climate change on species, requires that we quantify range‐wide patterns of genetic diversity and identify the ecological, environmental, and historical factors that have contributed to it. Here, we generate baseline data on polar bear population structure across most Canadian subpopulations (n = 358) using 13,488 genome‐wide single nucleotide polymorphisms (SNPs) identified with double‐digest restriction site‐associated DNA sequencing (ddRAD). Our ddRAD dataset showed three genetic clusters in the sampled Canadian range, congruent with previous studies based on microsatellites across the same regions; however, due to a lack of sampling in Norwegian Bay, we were unable to confirm the existence of a unique cluster in that subpopulation. These data on the genetic structure of polar bears using SNPs provide a detailed baseline against which future shifts in population structure can be assessed, and opportunities to develop new noninvasive tools for monitoring polar bears across their range.
High genetic diversity and stable Pleistocene distributional ranges in the widespread Mexican red oakQuercus castaneaNée (1801) (Fagaceae)
Authors: Peñaloza‐Ramírez Juan Manuel , Rodríguez‐Correa Hernando , González‐Rodríguez Antonio , Rocha‐Ramírez Víctor , Oyama Ken 
Published: March 2020

AbstractThe Mexican highlands are areas of high biological complexity where taxa of Nearctic and Neotropical origin and different population histories are found. To gain a more detailed view of the evolution of the biota in these regions, it is necessary to evaluate the effects of historical tectonic and climate events on species. Here, we analyzed the phylogeographic structure, historical demographic processes, and the contemporary period, Last Glacial Maximum (LGM) and Last Interglacial (LIG) ecological niche models ofQuercus castanea, to infer the historical population dynamics of this oak distributed in the Mexican highlands. A total of 36 populations ofQ. castaneawere genotyped with seven chloroplast microsatellite loci in four recognized biogeographic provinces of Mexico: the Sierra Madre Occidental (western mountain range), the Central Plateau, the Trans‐Mexican Volcanic Belt (TMVB, mountain range crossing central Mexico from west to east) and the Sierra Madre del Sur (SMS, southern mountain range). We obtained standard statistics of genetic diversity and structure and tested for signals of historical demographic expansions. A total of 90 haplotypes were identified, and 29 of these haplotypes were restricted to single populations. The within‐population genetic diversity was high (meanhS = 0.72), and among‐population genetic differentiation showed a strong phylogeographic structure (NST = 0.630 > GST = 0.266;p < .001). Signals of demographic expansion were identified in the TMVB and the SMS. The ecological niche models suggested a considerable percentage of stable distribution area for the species during the LGM and connectivity between the TMVB and the SMS. High genetic diversity, strong phylogeographic structure, and ecological niche models suggest in situ permanence ofQ. castaneapopulations with large effective population sizes. The complex geological and climatic histories of the TMVB help to explain the origin and maintenance of a large proportion of the genetic diversity in this oak species.
Friend or foe? A parasitic wasp shifts the cost/benefit ratio in a nursery pollination system impacting plant fitness
Authors: Villacañas de Castro Carmen , Hoffmeister Thomas S. 
Published: March 2020

AbstractNursery pollination systems are species interactions where pollinators also act as fruit/seed herbivores of the plant partner. While the plants depend on associated insects for pollination, the insects depend on the plants’ reproductive structures for larval development. The outcome of these interactions is thus placed on a gradient between mutualism and antagonism. Less specialized interactions may fluctuate along this gradient with the ecological context, where natural enemies can play an important role. We studied whether a natural enemy may impact the level of seed consumption of a nursery pollinator and how this in turn may influence individual plant fitness. We used the plant Silene latifolia, its herbivore Hadena bicruris, and its ectoparasitoid Bracon variator as a model plant–herbivore–natural enemy system. We investigated seed output, germination, survival, and flower production as proxies for individual plant fitness. We show that B. variator decreases the level of seed consumption by H. bicruris larvae which in turn increased seed output in S. latifolia plants, suggesting that parasitism by B. variator may act as a regulator in the system. However, our results also show that plant survival and flower production decrease with higher seed densities, and therefore, an increase in seed output may be less beneficial for plant fitness than estimated from seed output alone. Our study should add another layer to the complex discussion of whether parasitoids contribute to plant fitness, as we show that taking simple proxies such as seed output is insufficient to determine the net effect of multitrophic interactions.
Exhaustive extraction of cyclopeptides from Amanita phalloides: Guidelines for working with complex mixtures of secondary metabolites
Authors: Scott Chialvo Clare H. , Griffin Logan H. , Reed Laura K. , Ciesla Lukasz 
Published: March 2020

Abstract

Understanding plant‐insect interactions is an active area of research in both ecology and evolution. Much attention has been focused on the impact of secondary metabolites in the host plant or fungi on these interactions. Plants and fungi contain a variety of biologically active compounds, and the secondary metabolite profile can vary significantly between individual samples. However, many experiments characterize the biological effects of only a single secondary metabolite or a subset of these compounds.

Here, we develop an exhaustive extraction protocol using an accelerated solvent extraction protocol to recover the complete suite of cyclopeptides and other secondary metabolites found in Amanita phalloides (death cap mushrooms) and compare its efficacy to the “Classic” extraction method used in earlier works.

We demonstrate that our extraction protocol recovers the full suite of cyclopeptides and other secondary metabolites in A. phalloides unlike the “Classic” method that favors polar cyclopeptides.

Based on these findings, we provide recommendations for how to optimize protocols to ensure exhaustive extracts and also the best practices when using natural extracts in ecological experiments.
Transcriptional analyses reveal the molecular mechanism governing shade tolerance in the invasive plant Solidago canadensis
Authors: Wu Miao , Li Zeyu , Wang Jianbo 
Published: March 2020

AbstractSolidago canadensis is an invasive plant that is capable of adapting to variable light conditions. To elucidate the shade tolerance mechanism in S. canadensis at the molecular level, transcriptome analyses were performed for leaves growing under natural light and three shade level conditions. Many differentially expressed genes (DEGs) were found in the comparative analysis, including those involved in photosynthesis, antioxidant, and secondary metabolism of phenol‐ and flavonoid‐related pathways. Most genes encoding proteins involved in photosynthesis, such as photosystem I reaction center subunit (Psa), photosystem II core complex protein (Psb), and light‐harvesting chlorophyll protein (Lhca and Lhcb), and reactive oxygen species (ROS) scavenging‐related enzymes, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), were upregulated with the shade levels. Furthermore, most of the DEGs related to secondary metabolite synthesis were also upregulated in the shade conditions. Our study indicates that S. canadensis can respond to shade stress by modulating the expression of several photosynthesis‐related, free radical scavenging‐related, and secondary metabolism‐related genes; thus, this species has the ability to adapt to different light conditions.
Changes in oxygen uptake kinetics after exercise caused by differences in loading pattern and exercise intensity
Authors: Ichikawa Yuri , Maeda Tomoko , Takahashi Tetsuya , Ashikaga Kohei , Tanaka Shiori , Sumi Yuki , Itoh Haruki 
Published: March 2020

AbstractAimsThe kinetics of recovery‐period oxygen uptake (VO2) are affected by the O2 deficit generated during exercise. However, studies using ramp tests (RTs) and constant work rate tests (CT) have differently characterized VO2 responses to increased exercise intensity differently. We used these two types of loading patterns to investigate the effects of low‐intensity, medium‐intensity, and high‐intensity exercises on the half time (T1/2) of recovery‐period VO2 and the mechanism.Methods and resultsTen healthy men aged 21.2 ± 0.9 years underwent symptom‐limited cardiopulmonary exercise tests with the ramp protocol to determine their anaerobic threshold. All subjects subsequently underwent three submaximal RT and CT at low, moderate, and high intensities. In all RTs, subjects began exercise by warming up (20 W). In CT, T1/2 was significantly lengthened as exercise intensity increased (CT‐low: 34.0 ± 3.9 s, CT‐moderate: 39.5 ± 3.5 s, CT‐high:44.6 ± 4.2 s; P < 0.01, ANOVA), whereas no significant change was observed in RT, which began with the same work rate (RT‐low: 46.0 ± 5.7 s, RT‐moderate: 45.7 ± 4.8 s, RT‐high: 44.6 ± 3.5 s, RT‐max: 44.8 ± 3.2 s; P = 0.868, ANOVA). Only high‐intensity exercise resulted in two components (the fast and slow components) of VO2 decay, reflecting the increased O2 deficit by anaerobic metabolism.ConclusionsThe exercise intensity at the beginning of an exercise affects early recovery‐period VO2, which is a fast component. The T1/2 of recovery‐period VO2 occurs during the fast component, and an increase in O2 deficit affects both the fast and slow components, lengthening the T1/2. The T1/2 of recovery‐period VO2 in CT at moderate or high intensities, even if not symptom limited, can be used to evaluate exercise intolerance and early occurrence of anaerobic metabolism. Submaximal exercise tests may be considered as convenient methods for evaluating exercise tolerance in patients with cardiac failure.