bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitrogen stable isotope turnover and discrimination in lizards
Authors: Warne Robin W. , Wolf Blair O. 
Published: December 2020

RationaleNitrogen stable isotope ratio (δ15N) processes are not well described in reptiles, which limits reliable inference of trophic and nutrient dynamics. In this study we detailed δ15N turnover and discrimination (Δ15N) in diverse tissues of two lizard species, and compared these results with previously published carbon data (δ13C) to inform estimates of reptilian foraging ecology and nutrient physiology.MethodsWe quantified 15N incorporation and discrimination dynamics over 360 days in blood fractions, skin, muscle, and liver of Sceloporus undulatus and Crotaphytus collaris that differed in body mass. Tissue samples were analyzed on a continuous flow isotope ratio mass spectrometer.ResultsΔ15N for plasma and red blood cells (RBCs) ranged between +2.7 and +3.5‰; however, skin, muscle, and liver did not equilibrate, hindering estimates for these somatic tissues. 15N turnover in plasma and RBCs ranged from 20.7 ± 4 to 303 ± 166 days among both species. Comparison with previously published δ13C results for these same samples showed that 15N and 13C incorporation patterns were uncoupled, especially during winter when hibernation physiology could have played a role.ConclusionsOur results provide estimates of 15N turnover rates and discrimination values that are essential to using and interpreting isotopes in studies of diet reconstruction, nutrient allocation, and trophic characterization in reptiles. These results also suggest that somatic tissues can be unreliable, while life history shifts in nutrient routing and metabolism potentially cause 15N and 13C dynamics to be decoupled.
Construction of the Copper‐Functionalized Covalent Organic Framework Used as a Heterogeneous Catalyst for Click Reaction
Authors: Gao Tingjun , Su Xiaofang , Xu Huanjun , Hu Hui , Zeng Chaoyuan , Gao Yanan 
Published: December 2020

AbstractFunctional modification of the covalent organic frameworks (COFs) has become an efficient strategy to expand its applications in various fields. In this investigation, an imine linked T−D COF has been synthesized via solvothermal method using 2,4,6‐tris(4‐aminophenyl)pyridine (TAPP) and 2,6‐dihydroxynaphthalene‐1,5‐dicarbaldehyde (DHNDA) as building blocks. While synthesizing T‐D COF, hydroxyl groups are strategically introduced to the adjacent sites of −C=N− bonds in the framework. Such a special structure enables a strong coordination between the loaded copper metal ion and the hydroxyl groups together with imine bounds in the COF layered structure. The obtained copper‐containing COF, (Cu@T−D COF) hybrid material was used as an efficient heterogeneous catalyst for the alkyne‐azide click chemistry reactions and showed excellent catalytic activity in methanol/water medium. Furthermore, this Cu@T−D COF is stable and easily recycled and reused without loss of its catalytic activity.
Improved Synthesis of Bay‐Monobrominated Perylene Diimides
Authors: Fujimoto Keisuke , Uchida Kentaro , Nakamura Mayuko , Inuzuka Toshiyasu , Uemura Naohiro , Sakamoto Masami , Takahashi Masaki 
Published: December 2020

AbstractThe work presents the development of practical synthetic methods toward bay‐monobrominated perylene diimides (PDIs) that have been regarded as important synthetic intermediates for the fabrication of new photonic, optoelectronic, and photovoltaic materials. In the case of PDIs with long branched N‐alkyl solubilizers, bromination using N‐bromosuccinimide (NBS) and FeCl3 successfully provided the corresponding monobromides. This protocol improved the reaction outcomes in terms of product yield and operational easiness, superior to the conventional ones with liquid bromine. Alternatively, imidation of the corresponding dianhydride, easily prepared through monobromination of perylene‐3,4,9,10‐tetrabenzyl ester (PTE), recorded high efficiency for generation of PDI monobromides without solubilizing N‐substituents. This complementary method made it possible to access a series of new PDI monobromides which had been unobtainable through existing methods.
A feedback view of behavioural distortions from perceived public service gaps at ‘street‐level’ policy implementation: The case of unintended outcomes in public schools
Authors: Bianchi Carmine , Salazar Rua Robinson 
Published: December 2020

AbstractThis paper discusses the limitations and risks associated with the use of output‐oriented measures to assess public school performance. In particular, it questions the capability of the performance measures set by external institutions, with respect to schools, to support sustainable educational outcomes. To this end, the ‘street‐level bureaucracy’ theory is used in the paper as a basis to analyse the behavioural distortions generated by perceived public service gaps at school level policy implementation. Such unintended behavioural effects are often a major cause of disappointing outcomes when test‐based accountability systems are adopted. In the second part of the paper, an insight model referred to a hypothetic medium‐sized public school located in a poor area in Colombia is used to illustrate how a feedback approach to school performance measurement can support decision‐makers to pursue sustainable education outcomes and to prevent behavioural distortions from perceived public service gaps at ‘street‐level’ policy implementation. This analysis outlines an alternative approach to school performance measurement that might help policy makers in extending the domain of governmental benchmarks to performance measures and collaborative efforts that reflect the challenges of holistic education in the context where public schools are located.
Visualizing the food landscape of Durham, North Carolina
Authors: Graves Joseph L. , Templeton Gizem , Davis Lauren , Kim Seong‐Tae 
Published: December 2020

AbstractIn partnership with community leaders of Durham, North Carolina, the Duke World Food Policy Center is creating a Durham Food Justice Plan (DFJP) for envisioning an equitable food system. The Food Justice plan serves to incorporate Durham's local food history in terms of combating historical and present injustices in the food system. We propose creating an integrative, interactive visual for DFJP to view the food landscape of Durham, which will be utilized to study its relationships with the people living in the area where these establishments reside. We created a food landscape platform in Tableau using multisource data including Durham's food vendor data from North Carolina's Department of Commerce and census data for demographic data, neighborhood labels, and street and highways. We incorporated the Google Geocoding API and the aggregated information based on census blocks and tracts in visualization. We produced a variety of maps and graphs to highlight diverse relationships. The food landscape visualization allows us to see interactive patterns among food vendors and demographic data in Durham. We expect to utilize the developed landscape visual for insightful statistical analysis on food inequity issues.
Innovationen zum optimalen Einsatz des wetterfesten Baustahls im Stahl‐ und Verbundbrückenbau
Authors: Ungermann Dieter , Hatke Peter , Knyazeva Marina , Walther Frank , Lebelt Peter , Gehrke Jörg 
Published: December 2020

AbstractIm Rahmen des gleichnamigen Forschungsprojekts „Innovationen zum optimalen Einsatz des wetterfesten Baustahls im Stahl‐ und Verbundbrückenbau“ wurden wesentliche Aspekte zur besseren Anwendung des wetterfesten Baustahls im Stahl‐ und Verbundbrückenbau untersucht. Neben aktuellen Analysen zur Bildung der korrosionshemmenden Deckschicht in der heutigen Atmosphäre erfolgte die Qualifizierung zweier geometrieunabhängiger und zerstörungsfreier Messtechniken zur Rissdetektion unterhalb der kompakten Deckschicht und deren Verifizierung an realen Brückenbauwerken. Außerdem wurden Untersuchungen zur Optimierung der Haftreibungszahlen gleitfest vorgespannter Verbindungen von wetterfestem Baustahl durchgeführt. Grundsätzlich bietet der Einsatz von wetterfestem Baustahl durch die natürliche Bildung seiner fest haftenden und korrosionshemmenden Deckschicht sowohl wirtschaftliche als auch ökologische Vorteile im Vergleich zu organisch beschichtetem Baustahl, insbesondere bezogen auf die heutigen Nutzungsdauern im Brückenbau. In diesem Aufsatz sind die wesentlichen Forschungsergebnisse zusammengefasst, um den nachhaltigen Einsatz und die Vorzüge von wetterfestem Baustahl im Stahl‐ und Verbundbrückenbau unter den Einsatzbedingungen der aktuellen natürlichen Atmosphäre zu belegen.
Tragende 3D‐Druck‐Verbindungsknoten für Metallanschlussstäbe
Authors: Laufs Wilfried 
Published: December 2020

AbstractDer Beitrag nimmt Bezug auf die Frage, inwieweit aus Sicht der Tragwerksplanung der rasante Fortschritt im Bereich des 3D‐Drucks auch auf die Verbindungstechnik im Bauwesen (Metallbau) übertragen werden kann und welche neuen Möglichkeiten sich für den Tragwerksplaner hieraus ergeben. Dabei hilft der Ansatz der digitalen Fabrikation, nämlich Entwurf und Berechnung digital parametrisch vorab bereits so aufzuarbeiten, dass die 3D‐Geometrien dann direkt vom 3D‐Drucker eingelesen werden können – von der frühen Entwurfsphase bis hin zur Werkbank ist alles vernetzt. Je nach Projekt lassen sich Freiformen wirtschaftlich programmieren, da auch Verschraubung und weitere Anschlusselemente zu benachbarten Konstruktionsschichten direkt mit integriert werden können und somit Fabrikationsschritte reduzieren. Derzeit gibt es erst wenig mit 3D‐Printknoten gebaute Beispiele, von denen einige temporäre Projekte hier beschrieben werden. Ebenfalls werden erste axiale Zug‐ und Dreipunktbiegeversuche an Kunststoffproben ohne und mit Faserverstärkung samt ihrer beobachteten Versagensformen vorgestellt. Aus Sicht des Metallbaus sind noch viele offene Fragen zu Materialfestigkeit, Dauerhaftigkeit, Langzeit‐Witterungsbeständigkeit und Brandschutz solcher 3D‐Druckteile zu erforschen, damit geeignete Materialien und verlässliche Druckprozesse in der nahen Zukunft auch bauaufsichtlich zugelassen werden können, um eine breitere Praxisanwendung zu ermöglichen.
Using numerical modeling for asset management of buried prestressed concrete cylinder pipes
Authors: Hajali Masood , Abi Shdid Caesar 
Published: December 2020

AbstractPrestressed Concrete Cylinder Pipes (PCCP) form the backbone of water and wastewater infrastructure networks in North America. Failure of buried PCCP is a common occurrence due to structural deterioration or manufacturing defects. To mitigate the serious effects of such failures, owners and operators of these networks use risk curves to predict the failure of PCCP when given a certain level of deterioration by field inspectors. The current problem lies in the fact that asset management using such risk curves lacks accuracy and requires costly and time‐consuming field inspections. A solution is presented in this study that bypasses the need for such risk curves by using computational modeling in conjunction with flow measurement devices installed inside pipe networks. The three‐dimensional computational model uses nonlinear finite elements to simulate the behavior of buried PCCP under combined internal and external loading. The method is validated using experimental test results of full‐scale PCCP specimens. Comparison of several key structural health indicators shows close agreement of the developed model with experimental results. The study demonstrates that the developed approach can predict with relative accuracy and time efficiency the deterioration levels of different pipe segments under realistic loading conditions. This approach eliminates the need for risk curves that require time consuming and costly field inspections, and allows for more effective asset management through on‐time maintenance and replacement of such important infrastructure facilities by their public and private owners.
Poria cocos (Fuling) targets TGFβ/Smad7 associated collagen accumulation and enhances Nrf2‐antioxidant mechanism to exert anti‐skin aging effects in human dermal fibroblasts
Authors: Fang Chien‐Liang , Paul Catherine Reena , Day Cecilia Hsuan , Chang Ruey‐Lin , Kuo Chia‐Hua , Ho Tsung‐Jung , Hsieh Dennis Jine‐Yuan , Viswanadha Vijaya Padma , Kuo Wei‐Wen , Huang Chih‐Yang 
Published: December 2020

AbstractOxidative stress is a major cause of aging related skin injuries. Hydrogen peroxide related ROS accumulation triggers increase in matrix metalloproteinases and elevated collagen degradation, which is a characteristic of skin aging. In this study, we investigated the protective effect of Poria cocos, used widely in the treatment of inflammatory diseases, against H2O2 induced oxidative stress. The aqueous extract of dried P. cocos was obtained by heating 10 g in 500 ml of distilled water. The mixture was evaporated up to 400 ml and the remaining 100 ml was filtered through muslin cloth repeatedly to obtain a clear aqueous extract of the P. cocos. Hs68 human dermal fibroblast cells were challenged with 100 μM of H2O2 for 24 h. Following H2O2 challenge, the cells were treated with increasing concentration of P. cocos extract (100–400 μg/ml) for 24 h. P. cocos extract hindered the H2O2 induced cell death significantly that was correlated with reduction in ROS accumulation. Western blot analysis show that P. cocos extract suppressed the expression of metallomatrix proteinases, inflammatory markers and skin aging markers, but increased TGF‐β1 levels and antioxidant related proteins. These data suggest that P. cocos is effective in attenuating oxidative stress associated skin aging effects and may be a potential agent in cosmetics products.
Development of fragility curves of land‐based wind turbines with tuned mass dampers under cyclone and seismic loading
Authors: Martín del Campo J. Osvaldo , Pozos‐Estrada Adrián , Pozos‐Estrada Oscar 
Published: December 2020

AbstractPassive damping systems have been widely studied to improve the response of wind turbine structures under operational conditions. However, there is insufficient information on how these systems enhance reliability for extreme loads. Wind farm construction has been growing rapidly in recent decades, thereby moving wind turbine structures to sites with higher seismic and hurricane hazards. This research presents a numerical study performed on three land‐based wind turbines, similar to typical turbines installed in Mexican wind farms, under cyclone‐induced wind and earthquake action. The fictional location of the turbines is justified by the wind capacity distribution of Mexico, which is a country with high seismic and tropical cyclone risk. The wind field is simulated from semiempirical mean velocity models, and the ground motion records are obtained from real events recorded near the assumed site. All the time history analyses assume that the turbines are in parked condition. The results indicate that a fragility reduction of approximately 80% can be achieved under cyclone‐induced winds when passive damping systems are added to the structure, and that the fragility reduction is significantly less under seismic action.
Imaging as a tool to accelerate the translation of extracellular vesicle‐based therapies for central nervous system diseases
Authors: Gao Yue , Chu Chengyan , Jablonska Anna , Bulte Jeff W. M. , Walczak Piotr , Janowski Miroslaw 
Published: December 2020

AbstractExtracellular vesicles (EVs) are natural and diverse lipid bilayer‐enclosed particles originating from various cellular components and containing an abundance of cargoes. Due to their unique properties, EVs have gained considerable interest as therapeutic agents for a variety of diseases, including central nervous system (CNS) disorders. Their therapeutic value depends on cell origin but can be further enhanced by enrichment of cargo when used as drug carriers. Therefore, there has been significant effort directed toward introducing them to clinical practice. However, it is essential to avoid the failures we have seen with whole‐cell therapy, in particular for the treatment of the CNS. Successful launching of clinical studies is contingent upon the understanding of the biodistribution of EVs, including their uptake and clearance from organs and specific homing into the region of interest. A multitude of noninvasive imaging methods has been explored in vitro to investigate the spatio‐temporal dynamics of EVs administered in vivo. However, only a few studies have been performed to track the delivery of EVs, especially delivery to the brain, which is the most therapeutically challenging organ. We focus here on the use of advanced imaging techniques as an essential tool to facilitate the acceleration of clinical translation of EV‐based therapeutics, especially in the CNS arena.This article is categorized under:
Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease
Diagnostic Tools > in vivo Nanodiagnostics and Imaging
Role of microRNAs in the pathophysiology of addiction
Authors: Gowen Austin M. , Odegaard Katherine E. , Hernandez Jordan , Chand Subhash , Koul Sneh , Pendyala Gurudutt , Yelamanchili Sowmya V. 
Published: December 2020

AbstractAddiction is a chronic and relapsing brain disorder characterized by compulsive seeking despite adverse consequences. There are both heritable and epigenetic mechanisms underlying drug addiction. Emerging evidence suggests that non‐coding RNAs (ncRNAs) such as microRNAs (miRNAs), long non‐coding RNAs, and circular RNAs regulate synaptic plasticity and related behaviors caused by substances of abuse. These ncRNAs modify gene expression and may contribute to the behavioral phenotypes of addiction. Among the ncRNAs, the most widely researched and impactful are miRNAs. The goal in this systematic review is to provide a detailed account of recent research involving the role of miRNAs in addiction.This article is categorized under:
RNA Interactions with Proteins and Other Molecules > Small Molecule‐RNA Interactions
RNA in Disease and Development > RNA in Disease
Socioeconomically Informed Use of Geostatistics to Track Adaptation of Resource-Poor Communities to Climate Change
Authors: Chari Martin Munashe , Hamandawana Hamisai , Zhou Leocadia 
Published: December 2020

AbstractAs the Green Climate Fund continues to make concerted efforts to leverage funding for resource-constrained communities in the global south under the aegis of increasing climate change impacts in sub-Saharan Africa, there is urgent and compelling need for tools that assist organizations to track the effectiveness of adaptation interventions in reducing vulnerability. This chapter offers a cost-effective methodology to track adaptation by using a case-study-based identification of communities with diminishing coping capacities in Raymond Mhlaba Local Municipality in the Eastern Cape Province of South Africa. Multistep geostatistical techniques were utilized in the ArcGIS 10.5 software environment to rank and spatialize changes in adaptation by using demographic census data for the years 2001 and 2011. Results of the analysis revealed that 12 communities had declining or static adaptive capacities between 2001 and 2011, while 10 communities had long-term decrease in adaptive capacities from 2001 to 2011 from a sampling universe of 134 communities. These findings are important because they demonstrate that the methodology can be effectively used to provide actionable information on the prevalence of low adaptation capacities at appropriate temporal and spatial scales, in order to guide the allocation of limited resources to the most deserving communities.
Community Adaptation to Climate Change: Case of Gumuz People, Metekel Zone, Northwest Ethiopia
Authors: Wagino Abbebe Marra , Amanuel Teshale W. 
Published: December 2020

AbstractThe effect of climate change on agricultural-dependent communities is immense. Ethiopia in which more than 85% of its population is agrarian is affected by climate change. Communities in different parts of the country perceived climate change and practice different climate change adaptation strategies. This chapter was initiated to identify adaptation strategy to the impact of changing climate. Data on a total of 180 households were gathered using structured and semi-structured questioners. Focus group discussion and key informant interview were also used for data collection. Climatic data from the nearest meteorological stations of the area were collected and used in this chapter. The collected data were analyzed using descriptive and inferential statistical methods. The upshot indicated that all the respondent communities experienced at least one of autonomous/self-adaptation strategies to cope and live with the impacts of changing climate. Though 33.6% complained on its accessibility and pricing, 66.4% of the respondents reviled as they do not have any awareness on improved agricultural technologies. The major adaptation strategies identified were collecting and using of edible wild plants and other forest products, hunting, renting/selling of own farm lands, livestock sell, selling of household materials/assets, collecting and selling of wood and wood products and depending on well-off relatives, using drought-resistant crop variety, changing cropping calendar, replanting/sowing, and increasing farmland size. Nevertheless, the communities are not yet fully aware and accessed to policy-driven options for climate change adaptation. Although they used different autonomous adaptation mechanisms, the households are not resilient to the current and perceived climate change. Finally, based on the findings, the recommendation is that besides encouraging the existing community-based adaptation strategies planned adaptation strategies have to be implemented: such as early-warning and preparedness programs have to be effectively implemented in the area, introduction of different drought-resistant locally adapted food crop varieties, and expansion of large-scale investment in the area has to be checked, and give due recognition to forest ecosystem–based adaptation mechanisms of the local community in the area.
Relaxing cosmological neutrino mass bounds with unstable neutrinos
Authors: Escudero Miguel , Lopez-Pavon Jacobo , Rius Nuria , Sandner Stefan 
Published: December 2020

Abstract
At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model (ΛCDM), the Planck collaboration reports ∑mv< 0.12 eV at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable neutrinos, with lifetimes shorter than the age of the universe τν ≲ tU, represent a particle physics avenue to relax this constraint. Motivated by this fact, we present a taxonomy of neutrino decay modes, categorizing them in terms of particle content and final decay products. Taking into account the relevant phenomenological bounds, our analysis shows that 2-body decaying neutrinos into BSM particles are a promising option to relax cosmological neutrino mass bounds. We then build a simple extension of the type I seesaw scenario by adding one sterile state ν4 and a Goldstone boson ϕ, in which νi→ ν4ϕ decays can loosen the neutrino mass bounds up to ∑mv ∼ 1 eV, without spoiling the light neutrino mass generation mechanism. Remarkably, this is possible for a large range of the right-handed neutrino masses, from the electroweak up to the GUT scale. We successfully implement this idea in the context of minimal neutrino mass models based on a U(1)μ−τ flavor symmetry, which are otherwise in tension with the current bound on ∑mv.