bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sustainable individualized instruction of biochemistry: A framework for recruiting, training, and utilizing undergraduate teaching assistants
Authors: Ahmed Ahmed M. , Blankenship Jim 
Published: June 2019

AbstractIndividualized instruction of biochemistry has been a promising alternative to large lecture format classes at our institution. The challenge, however, is that individualized instruction courses have larger staff requirements, which can be infeasible under the current scope of educational budget and human resource constraints. In this article, we highlight how we have met those larger staff requirements in a sustainable way by utilizing undergraduate teaching assistants. We also provide an effective framework for recruiting, training, and utilizing undergraduate teaching assistants, which can be replicated in other contexts. © 2019 International Union of Biochemistry and Molecular Biology, 47(5):560–564, 2019.
UPLC–QTOF/MS‐based metabolomics reveals the mechanism of chronic unpredictable mild stress‐induced hypertension in rats
Authors: Wu Qiong , Xia De‐Meng , Lan Fen , Wang Yang‐Kai , Tan Xing , Sun Jia‐Cen , Wang Wei‐Zhong , Wang Rui , Peng Xiao‐Dong , Liu Min 
Published: June 2019

AbstractHypertension is a common chronic disease, and it is the strongest risk factor for cardiovascular disease. Recently, the number of patients with hypertension‐related complications has increased significantly, adding a heavy burden to the public health system. It is known that chronic stress plays an important role in the pathogenesis of cardiovascular diseases such as hypertension and stroke. However, the impact of hypertension on the dysfunctions induced by chronic stress remains poorly understood. In this study, using LC–MS‐based metabolomics, we established a chronic stress model to demonstrate the mechanisms of stress‐induced hypertension. We found that 30 metabolites in chronically stressed rats were changed; of these metabolites, seven had been upregulated, and 23 had been downregulated, including amino acids, phospholipids, carnitines and fatty acids, many of which are involved in amino acid metabolism, cell membrane injury, ATP supply and inflammation. These metabolites are engaged in dysregulated pathways and will provide a targeted approach to study the mechanism of stress‐induced hypertension.
Lessons from a Minimal Genome: What Are the Essential Organizing Principles of a Cell Built from Scratch?
Authors: Tarnopol Rebecca L. , Bowden Sierra , Hinkle Kevin , Balakrishnan Krithika , Nishii Akira , Kaczmarek Caleb J. , Pawloski Tara , Vecchiarelli Anthony G. 
Published: June 2019

AbstractOne of the primary challenges facing synthetic biology is reconstituting a living system from its component parts. A particularly difficult landmark is reconstituting a self‐organizing system that can undergo autonomous chromosome compaction, segregation, and cell division. Here, we discuss how the syn3.0 minimal genome can inform us of the core self‐organizing principles of a living cell and how these self‐organizing processes can be built from the bottom up. The review underscores the importance of fundamental biology in rebuilding life from its molecular constituents.
Survival of glioblastoma cells in response to endogenous and exogenous oxidative challenges: possible implication of NMDA receptor‐mediated regulation of redox homeostasis
Authors: Dalavaikodihalli Nanjaiah Nandakumar , Ramaswamy Palaniswamy , Goswami Kalyan , Fathima K Hurmath , Borkotokey Monjuri 
Published: June 2019

AbstractCancer cells are highly metabolically active and produce high levels of reactive oxygen species (ROS). Drug resistance in cancer cells is closely related to their redox status. The role of ROS and its impact on cancer cell survival seems far from elucidation. The mechanisms through which glioblastoma cells overcome aberrant ROS and oxidative stress in a milieu of hypermetabolic state is still elusive. We hypothesize that the formidable growth potential of glioma cells is through manipulation of tumor microenvironment for its survival and growth, which can be attributed to an astute redox regulation through a nexus between activation of N‐methyl‐d‐aspartate receptor (NMDAR) and glutathione (GSH)‐based antioxidant prowess. Hence, we examined the NMDAR activation on intracellular ROS level, and cell viability on exposure to hydrogen peroxide (H2O2), and antioxidants in glutamate‐rich microenvironment of glioblastoma. The activation of NMDAR attenuated the intracellular ROS production in LN18 and U251MG glioma cells. MK‐801 significantly reversed this effect. On evaluation of GSH redox cycle in these cells, the level of reduced GSH and glutathione reductase (GR) activity were significantly increased. NMDAR significantly enhanced the cell viability in LN18 and U251MG glioblastoma cells, by attenuating exogenous H2O2‐induced oxidative stress, and significantly increased catalase activity, the key antioxidant that detoxifies H2O2. We hereby report an unexplored role of NMDAR activation induced protection of the rapidly multiplying glioblastoma cells against both endogenous ROS as well as exogenous oxidative challenges. We propose potentiation of reduced GSH, GR, and catalase in glioblastoma cells through NMDAR as a novel rationale of chemoresistance in glioblastoma.
Monolithiation of 5,5′‐Dibromo‐2,2′‐bithiophene Using Flow Microreactors: Mechanistic Implications and Synthetic Applications
Authors: Nagaki Aiichiro , Jiang Yiyuan , Yamashita Hiroki , Takabayashi Naoshi , Takahashi Yusuke , Yoshida Jun-ichi 
Published: June 2019

AbstractThe lithiation of 5,5′‐dibromo‐2,2′‐bithiophene with one equivalent of an alkyllithium such as n‐BuLi or s‐BuLi was studied by varying the residence time in flow microreactors. With a short residence time, the product 2,2′‐bithiophene (3) derived from dilithiation was obtained preferentially and a significant amount of the starting material 5,5′‐dibromo‐2,2′‐bithiophene remained unchanged. An increase in the residence time caused a higher yield of the product 5‐bromo‐2,2′‐bithiophene derived from monolithiation with expense in the yields of 2,2′‐bithiophene and 5,5′‐dibromo‐2,2′‐bithiophene. The lithiation using MeLi gave the product 5‐bromo‐2,2′‐bithiophene preferentially even with a very short residence time.
Modular Manufacturing Platform for Continuous Synthesis and Analysis of Versatile Nanomaterials
Authors: von Bomhard Sibylle , Schramm Jonas , Bleul Regina , Thiermann Raphael , Höbel Peter , Krtschil Ulrich , Löb Patrick , Maskos Michael 
Published: June 2019

AbstractNanoparticular materials have a great potential in various fields including technical and biomedical applications; to meet the specific requirements, a good control over the particle characteristics is mandatory. Addressing this, a modular system for the automated and continuous synthesis, workup, and analysis of a broad range of nanoparticles was developed. Application examples of inorganic (silica) and organic (polymersomes, niosomes) nanoparticles demonstrate the versatility of the production platform. Modules for downstream processing via a falling‐film microreactor or tangential flow filtration are presented. The hydrodynamic size as a key parameter is acquired in real time, with an inline dynamic light scattering device. All modules are controlled and operated by a process control system.
CO2 Methanation in Microstructured Reactors – Catalyst Development and Process Design
Authors: Neuberg Stefan , Pennemann Helmut , Shanmugam Vetrivel , Thiermann Raphael , Zapf Ralf , Gac Wojciech , Greluk Magdalena , Zawadzki Witold , Kolb Gunther 
Published: June 2019

AbstractThe sulfur tolerance of mono‐ and bimetallic ruthenium catalysts for CO2 hydrogenation was investigated in microchannel reactors. H2S was selected as a model compound. It was found that a Ru/CeO2 catalyst deactivates rapidly. Ni was a much better additive to improve the catalyst stability compared to Rh and serves as a sulfur trap. The influence of the support was evaluated showing that a SiO2‐supported catalyst has a higher stability and better selectivity compared to CeO2 and TiO2. A plant concept was developed comprising two‐step methanation with a first adiabatic reactor stage followed by a plate heat‐exchanger reactor with integrated cooling which allows more than 97 % CO2 conversion. A pilot plant will be put into operation in connection with a biogas plant and an electrolyser of 50 kW power consumption.
Aktiv im Ruhestand
Authors: Gerhartz Wolfgang , Jäckel Klaus‐Peter 
Published: June 2019

Pensionierte Chemiker sind Couch Potatoes, Fernsehglotzer, Langeweiler und desinteressiert an Politik und Kultur. Wirklich?Wir – die Seniorexperten Chemie (Senior Expert Chemists; SEC) – sind zum größten Teil aus dem aktiven Berufsleben ausgeschieden. Aber: Wir sind aktiv, weltoffen und noch immer in die Naturwissenschaften, speziell in die Chemie und die Pharmazie, verliebt.
Schubtragfähigkeit von Ziegelmauerwerk mit teilweise aufliegender Deckenplatte
Authors: Pfetzing Thomas , Fehling Ekkehard , Meyer Udo Joachim 
Published: June 2019

AbstractIn order to investigate the influence of a partially supported slab on the in‐plane shear resistance of masonry walls, six shear tests on full scale walls were performed at the Chair of Structural Concrete of the University of Kassel in cooperation with ”Arbeitsgemeinschaft Mauerziegel“. The walls were made of large chamber clay masonry units and the depths of the partially supported slabs were different. The large chamber units are typically used for thermally insulated exterior walls, with the slabs only being partially supported. The influence of this constellation is not taken into account in shear capacity assessment according to the current version of Eurocode 6 for Germany. This article describes the test results and provides a comparison with Eurocode 6. In addition, the results of older shear tests on masonry walls made of vertically perforated units with eccentric load application were used.
Comparative phylogeography of five widespread tree species: Insights into the history of western Amazonia
Authors: Honorio Coronado Eurídice N. , Dexter Kyle G. , Hart Michelle L. , Phillips Oliver L. , Pennington R. Toby 
Published: June 2019

AbstractVarious historical processes have been put forth as drivers of patterns in the spatial distribution of Amazonian trees and their population genetic variation. We tested whether five widespread tree species show congruent phylogeographic breaks and similar patterns of demographic expansion, which could be related to proposed Pleistocene refugia or the presence of geological arches in western Amazonia. We sampled Otoba parvifolia/glycycarpa (Myristicaceae), Clarisia biflora, Poulsenia armata, Ficus insipida (all Moraceae), and Jacaratia digitata (Caricaceae) across the western Amazon Basin. Plastid DNA (trnH–psbA; 674 individuals from 34 populations) and nuclear ribosomal internal transcribed spacers (ITS; 214 individuals from 30 populations) were sequenced to assess genetic diversity, genetic differentiation, population genetic structure, and demographic patterns. Overall genetic diversity for both markers varied among species, with higher values in populations of shade‐tolerant species than in pioneer species. Spatial analysis of molecular variance (SAMOVA) identified three genetically differentiated groups for the plastid marker for each species, but the areas of genetic differentiation were not concordant among species. Fewer SAMOVA groups were found for ITS, with no detectable genetic differentiation among populations in pioneers. The lack of spatially congruent phylogeographic breaks across species suggests no common biogeographic history of these Amazonian tree species. The idiosyncratic phylogeographic patterns of species could be due instead to species‐specific responses to geological and climatic changes. Population genetic patterns were similar among species with similar biological features, indicating that the ecological characteristics of species impact large‐scale phylogeography.
Mammalian tolerance to humans is predicted by body mass: evidence from long‐term archives
Authors: Crees Jennifer J. , Turvey Samuel T. , Freeman Robin , Carbone Chris 
Published: June 2019

AbstractHumans are implicated as a major driver of species extinctions from the Late Pleistocene to the present. However, our predictive understanding of human‐caused extinction remains poor due to the restricted temporal and spatial scales at which this process is typically assessed, and the risks of bias due to “extinction filters” resulting from a poor understanding of past species declines. We develop a novel continent‐wide data set containing country‐level last‐occurrence records for 31 European terrestrial mammals across the Holocene (c.11,500 yr BP to present), an epoch of relative climatic stability that captures major transitions in human demography. We analyze regional extirpations against a high‐resolution database of human population density (HPD) estimates to identify species‐specific tolerances to changing HPD through the Holocene. Mammalian thresholds to HPD scale strongly with body mass, with larger‐bodied mammals experiencing regional population losses at lower HPDs than smaller‐bodied mammals. Our analysis enables us to identify levels of tolerance to HPD for different species, and therefore has wide applicability for determining biotic vulnerability to human impacts. This ecological pattern is confirmed across wide spatiotemporal scales, providing insights into the dynamics of prehistoric extinctions and the modern biodiversity crisis, and emphasizing the role of long‐term archives in understanding human‐caused biodiversity loss.
Disease avoidance, and breeding group age and size condition the dispersal patterns of western lowland gorilla females
Authors: Baudouin Alice , Gatti Sylvain , Levréro Florence , Genton Céline , Cristescu Romane H. , Billy Vincent , Motsch Peggy , Pierre Jean‐Sébastien , Le Gouar Pascaline , Ménard Nelly 
Published: June 2019

AbstractSocial dispersal is an important feature of population dynamics. When female mammals occur in polygynous groups, their dispersal decisions are conditioned by various female‐, male‐, and group‐related factors. Among them, the influence of disease often remains difficult to assess. To address this challenge, we used long‐term monitoring data from two gorilla populations (Gorilla gorilla gorilla) affected by infectious skin disease lesions. After controlling for other potentially influential factors, we investigated to which extent disease avoidance drives the dispersal decisions of gorilla females. We showed that the infection of a silverback of a breeding group by the skin disease increased the probability of adult females to emigrate. Moreover, adult females avoided breeding groups with a high prevalence of skin disease by emigrating from them and immigrating into healthier ones. Age of the breeding group was also an important factor. Adult females left older groups, near the end of a male tenure, to join younger ones led by younger fully grown silverbacks that could be of high reproductive and protective value. Our study highlights that, although females select for high‐quality males, disease avoidance is a critical driver of their dispersion decision.
Multifunctional cytokine production reveals functional superiority of memory CD4 T cells
Authors: Westerhof Lotus M , McGuire Kris , MacLellan Lindsay , Flynn Ashley , Gray Joshua I , Thomas Matthew , Goodyear Carl S , MacLeod Megan KL 
Published: June 2019

AbstractT cell protective immunity is associated with multifunctional memory cells that produce several different cytokines. Currently, our understanding of when and how these cells are generated is limited. We have used an influenza virus mouse infection model to investigate whether the cytokine profile of memory T cells is reflective of primary responding cells or skewed toward a distinct profile. We found that, in comparison to primary cells, memory T cells tended to make multiple cytokines simultaneously. Analysis of the timings of release of cytokine by influenza virus‐specific T cells, demonstrated that primary responding CD4 T cells from lymphoid organs were unable to produce a sustained cytokine response. In contrast CD8 T cells, memory CD4 T cells, and primary responding CD4 T cells from the lung produced a sustained cytokine response throughout the restimulation period. Moreover, memory CD4 T cells were more resistant than primary responding CD4 T cells to inhibitors that suppress T cell receptor signaling. Together, these data suggest that memory CD4 T cells display superior cytokine responses compared to primary responding cells. These data are key to our ability to identify the cues that drive the generation of protective memory CD4 T cells following infection.
Tissue‐specific production of MicroRNA‐155 inhibits melanocortin 5 receptor‐dependent suppressor macrophages to promote experimental autoimmune uveitis
Authors: Muhammad Fauziyya , Trivett Anna , Wang Dawei , Lee Darren J. 
Published: June 2019

AbstractTissue‐specific immune regulation is an important component of the immune response relevant to many areas of immunology. The focus of this study is on tissue‐specific mechanisms that contribute to autoimmune uveitis. Precise gene regulation is necessary for the proper expression of an inflammatory or regulatory response. This precision gene regulation can be accomplished by microRNA at the level of the mRNA transcript. miR‐155, in particular, has a complicated role in the immune response with positive and negative inflammatory effects. In this work, we identify a decrease in miR‐155 in suppressor macrophages and further examine how tissue‐specific production of miR‐155 impacts experimental autoimmune uveitis. Importantly, we show that eliminating miR‐155 expression by the target tissue before initiation reduces disease severity, but elimination of miR‐155 after the onset of inflammation does not alter the course of disease. Additionally, expression of miR‐155 by the target tissue before initiation is necessary for the induction of regulatory immunity that protects from further autoimmune disease, but not after the onset of inflammation. In summary, we find a MC5r‐dependent decrease in miR‐155 in postexperimental autoimmune uveitis APC, miR‐155 production by the target tissue is necessary for the initiation of autoimmune uveitis, and may have a role in establishing protective regulatory immunity.
A new droplet breakup phenomenon in electrokinetic flow through a microchannel constriction
Authors: Ji Xiang , Zhou Teng , Deng Yongbo , Shi Liuyong , Zhang Xianman , Woo Joo Sang 
Published: June 2019

AbstractA completely new droplet breakup phenomenon is reported for droplets passing through a constriction in an electrokinetic flow. The breakup occurs during the droplet shape recovery process past the constriction throat by the interplay of the dielectrophoretic stress release and the interface energy for droplets with smaller permittivity than that of the ambient fluid. There are conditions for constriction ratios and droplet size that the droplet breakup occurs. The numerical predictions provided here require experimental verification, and then can give rise to a novel microfluidic device design with novel droplet manipulations.
Continuous flow microfluidic cell inactivation with the use of insulating micropillars for multiple electroporation zones
Authors: Pudasaini Sanam , Perera A T K , Das Dhiman , Ng Sum Huan , Yang Chun 
Published: June 2019

AbstractElectroporation is a powerful tool for inactivating cells and transfecting biological cells and has applications in biology, genetic engineering, medicine, environment, and many others. We report a new continuous flow device embedded with insulating micropillars to achieve better performance of cell inactivation. The use of micropillars creates multiple electroporation zones with enhanced local electric field strengths. Using a model solution of Saccharomyces cerevisiae, we examined the inactivation performance of the device under various applied electric voltages and flow rates. Results from the numerical simulations and experiments showed that even with an induced transmembrane potential of 0.58 V, close to 63% of cell inactivation was achieved at a flow rate of 2.5 mL/h. This was higher than the 24% cell inactivation observed for a reference device without micropillars that was subjected to the same conditions.
Quantifying the dynamics of microtopography during a snowmelt event
Authors: Barneveld Robert J. , van der Zee Sjoerd E. A. T. M. , Stolte Jannes 
Published: June 2019

AbstractKnowledge of soil microtopography and its changes in space and over time is important to the understanding of how tillage influences infiltration, runoff generation and erosion. In this study, the use of a terrestrial laser scanner (TLS) is assessed for its ability to quantify small changes in the soil surface at high spatial resolutions for a relatively large surface area (100 m2). Changes in soil surface morphology during snow cover and melt are driven by frost heave, slaking, pressure exertion by the snowpack and overland flow (erosion and deposition). An attempt is undertaken to link these processes to observed changes at the soil surface. A new algorithm for soil surface roughness is introduced to make optimal use of the raw point cloud. This algorithm is less scale dependent than several commonly used roughness calculations. The results of this study show that TLSs can be used for multitemporal scanning of large surfaces and that small changes in surface elevation and roughness can be detected. Statistical analysis of the observed changes against terrain indices did not yield significant evidence for process differentiation. © 2019 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd. © 2019 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd.
Capturing the problems
Authors: Cozier Muriel 
Published: June 2019

AbstractAn audit is not always something that an organisation looks forward to. Having procedures or expenditures critiqued by an independent body has the potential to be nerve‐wracking. But the scrutiny can often lead to better decisions for the future. In this article, GHGS&T's Muriel Cozier looks at the findings from the audit of the past 10 years of European Union's climate action. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.
Escherichia coli Modulator of Drug Activity B (MdaB) Has Different Enzymological Properties to Eukaryote Quinone Oxidoreductases
Authors: Megarity Clare F. , Timson David J. 
Published: June 2019

AbstractSome quinone oxidoreductases exhibit negative cooperativity towards inhibitors. In human NQO1, this is mediated by flexibility around glycine‐150. Here we investigated the eubacterial orthologue, Modulator of Drug Activity B (MdaB) to determine if it shows cooperativity towards substrates or inhibitors and to investigate molecular recognition of the inhibitor, dicoumarol. Like human NQO1, MdaB did not show cooperativity towards substrates. However, unlike NQO1, it was only weakly inhibited by dicoumarol. Alanine‐127 in MdaB is the structurally equivalent residue to Gly‐150 in human NQO1. With the intention of increasing protein flexibility in MdaB, this alanine was altered to glycine. This change did not increase cooperativity towards inhibitors or NADPH. Based on structural alignment to NQO1 in complex with dicoumarol, an asparagine in the active site was changed to alanine to reduce steric hindrance. This change resulted in enhanced inhibition by dicoumarol, but the inhibition was not cooperative. Both changes were then introduced simultaneously. However, the additional increase in flexibility afforded by the change to glycine did not enable negative cooperativity towards dicoumarol. These results have implications for the evolution of quinone oxidoreductases and their potential use as biocatalysts.