bluuebunny/crossref_metadata_2025_split huggingface dataset:
Towards Sustainable High‐Performance Thermoplastics: Synthesis, Characterization, and Enzymatic Hydrolysis of Bisguaiacol‐Based Polyesters
Authors: Curia Silvio , Biundo Antonino , Fischer Isabel , Braunschmid Verena , Gübitz Georg M. , Stanzione Joseph F. 
Published: June 2018

AbstractThe utilization of wood‐derived building blocks (xylochemicals) to replace fossil‐based precursors is an attractive research subject of modern polymer science. Here, we demonstrate that bisguaiacol (BG), a lignin‐derived bisphenol analogue, can be used to prepare biobased polyesters with remarkable thermal properties. BG was treated with different activated diacids to investigate the effect of co‐monomer structures on the physical properties of the products. Namely, derivatives of adipic acid, succinic acid, and 2,5‐furandicarboxylic acid were used. Moreover, a terephthalic acid derivative was used for comparison purposes. The products were characterized by1H NMR spectroscopy, attenuated total reflectance FTIR spectroscopy, gel‐permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry to assess their structural and thermal properties in detail. The polymers showed glass‐transition temperatures ranging up to 160 °C and thermal stabilities in excess of 300 °C. Furthermore, the susceptibility of the polyester to enzymatic hydrolysis was investigated to assess the potential for further surface functionalization and/or recycling and biodegradation. Indeed, hydrolysis with two different enzymes from the bacteriaThermobifida cellulosilyticaled to the release of monomers, as quantified by HPLC. The results of this study indicate that our new polyesters represent promising renewable and biodegradable alternatives to petroleum‐based polyesters currently employed in the plastics industry, specifically for applications in which high‐temperature stability is essential to ensure overall system integrity.
Intraspinal serotonergic signaling suppresses locomotor activity in larval zebrafish
Authors: Montgomery Jacob E. , Wahlstrom‐Helgren Sarah , Wiggin Timothy D. , Corwin Brittany M. , Lillesaar Christina , Masino Mark A. 
Published: June 2018

ABSTRACTSerotonin (5HT) is a modulator of many vital processes in the spinal cord (SC), such as production of locomotion. In the larval zebrafish, intraspinal serotonergic neurons (ISNs) are a source of spinal 5HT that, despite the availability of numerous genetic and optical tools, has not yet been directly shown to affect the spinal locomotor network. In order to better understand the functions of ISNs, we used a combination of strategies to investigate ISN development, morphology, and function. ISNs were optically isolated from one another by photoconverting Kaede fluorescent protein in individual cells, permitting morphometric analysis as they developed in vivo. ISN neurite lengths and projection distances exhibited the greatest amount of change between 3 and 4 days post‐fertilization (dpf) and appeared to stabilize by 5 dpf. Overall ISN innervation patterns were similar between cells and between SC regions. ISNs possessed rostrally‐extending neurites resembling dendrites and a caudally‐extending neurite resembling an axon, which terminated with an enlarged growth cone‐like structure. Interestingly, these enlargements remained even after neurite extension had ceased. Functionally, application of exogenous 5HT reduced spinally‐produced motor nerve bursting. A selective 5HT reuptake inhibitor and ISN activation with channelrhodopsin‐2 each produced similar effects to 5HT, indicating that spinally‐intrinsic 5HT originating from the ISNs has an inhibitory effect on the spinal locomotor network. Taken together this suggests that the ISNs are morphologically mature by 5 dpf and supports their involvement in modulating the activity of the spinal locomotor network. © 2018 Wiley Periodicals, Inc. Develop Neurobiol, 2018
Calcium rises induced by AMPA and nicotine receptors in the ventral tegmental area show differences in mouse brain slices prenatally exposed to nicotine
Authors: Ipsen Theis H. , Polli Filip S. , Kohlmeier Kristi A. 
Published: June 2018

ABSTRACTNicotine exposure during gestation is associated with a higher risk of adverse behavioral outcomes including a heightened liability for dependency to drugs of abuse, which can exhibit drug‐specificity influenced by gender. This enhanced liability suggests that nicotine use during pregnancy alters neural development in circuits involved in motivation and reward‐based learning. The ventral tegmental area (VTA) is critical in motivated behaviors and we hypothesized that gestational exposure to nicotine alters the development of excitatory circuits in this nucleus. Accordingly, in VTA brain slices from male and female mice exposed to nicotine during the prenatal period (PNE) and controls, we compared cellular rises in calcium induced by AMPA receptor and nicotinic acetylcholine receptor (nAChR) stimulation by use of the ratiometric calcium binding dye, Fura‐2AM. We found that AMPA induced smaller amplitude calcium rises in the PNE VTA, which was an effect only detected in males. Further, while the amplitude did not vary between treatment and control in females, a greater number of cells responded with rises in calcium in the PNE. Conversely, the proportions of cells responding with calcium rises induced by nAChR stimulation did not change in either gender according to treatment. However, larger rises in calcium in PNE females were detected. When taken together our data show that excitatory signaling in the VTA is altered in a gender‐specific manner by PNE and suggest that alterations in signaling could play a role in drug‐specific differences in maladaptive, motivated behaviors exhibited by males and females born to mothers exposed to nicotine during pregnancy. © 2018 Wiley Periodicals, Inc. Develop Neurobiol 2018
Assessment of ethyl sulphate in hair as a marker for alcohol consumption using liquid chromatography–tandem mass spectrometry
Authors: Cappelle Delphine , Lai Foon Yin , Covaci Adrian , Vermassen Annemie , Crunelle Cleo L. , Neels Hugo , van Nuijs Alexander L.N. 
Published: June 2018

AbstractEthyl glucuronide (EtG) and ethyl sulphate (EtS) are 2 non‐oxidative and direct metabolites of ethanol. EtG is known to accumulate in hair and has proved to be a reliable biomarker for detection of chronic alcohol consumption. EtS has been analysed in blood and urine but has never been reported in hair. This article presents the first analytical assay based on liquid chromatography coupled to tandem mass spectrometry for the quantification of EtS in hair. Sample preparation, chromatographic, and mass spectrometric parameters, such as solid‐phase extraction, column type, and transitions were optimised. The method was validated according to the guidelines of the European Medicine Agency, fulfilling the requirements for limit of quantification (LOQ), linearity, accuracy, precision, carry‐over, matrix effects, and recovery. Linearity ranged from 5 to 500 pg mg−1 and the LOQ was achieved at 5 pg mg−1. The novel method was successfully applied to hair samples (n = 40) from patients treated for alcohol use disorders. EtS concentrations in hair ranged from 24 to 1776 pg mg−1, while EtG concentrations in hair ranged from 1 to 1149 pg mg−1. Hair concentrations of EtS and EtG were compared to assess the relationship between both biomarkers. There was a significant and positive correlation between EtS and EtG in hair, suggesting that EtS can be used as a biomarker for alcohol consumption. Relatively high basal EtS levels were observed in alcohol‐abstinent persons, comparable to what has been reported for EtG. The developed analytical procedure offers an alternative method to prove alcohol consumption using hair analysis.
Assessing historical and projected carbon balance of Alaska: A synthesis of results and policy/management implications
Authors: McGuire A. David , Genet Hélène , Lyu Zhou , Pastick Neal , Stackpoole Sarah , Birdsey Richard , D'Amore David , He Yujie , Rupp T. Scott , Striegl Robert , Wylie Bruce K. , Zhou Xiaoping , Zhuang Qianlai , Zhu Zhiliang 
Published: June 2018

AbstractWe summarize the results of a recent interagency assessment of land carbon dynamics in Alaska, in which carbon dynamics were estimated for all major terrestrial and aquatic ecosystems for the historical period (1950–2009) and a projection period (2010–2099). Between 1950 and 2009, upland and wetland (i.e., terrestrial) ecosystems of the state gained 0.4 Tg C/yr (0.1% of net primary production,NPP), resulting in a cumulative greenhouse gas radiative forcing of 1.68 × 10−3 W/m2. The change in carbon storage is spatially variable with the region of the Northwest Boreal Landscape Conservation Cooperative (LCC) losing carbon because of fire disturbance. The combined carbon transport via various pathways through inland aquatic ecosystems of Alaska was estimated to be 41.3 Tg C/yr (17% of terrestrialNPP). During the projection period (2010–2099), carbon storage of terrestrial ecosystems of Alaska was projected to increase (22.5–70.0 Tg C/yr), primarily because ofNPPincreases of 10–30% associated with responses to rising atmosphericCO2, increased nitrogen cycling, and longer growing seasons. Although carbon emissions to the atmosphere from wildfire and wetlandCH4were projected to increase for all of the climate projections, the increases inNPPmore than compensated for those losses at the statewide level. Carbon dynamics of terrestrial ecosystems continue to warm the climate for four of the six future projections and cool the climate for only one of the projections. The attribution analyses we conducted indicated that the response ofNPPin terrestrial ecosystems to rising atmosphericCO2(~5% per 100 ppmvCO2) saturates asCO2increases (between approximately +150 and +450 ppmv among projections). This response, along with the expectation that permafrost thaw would be much greater and release large quantities of permafrost carbon after 2100, suggests that projected carbon gains in terrestrial ecosystems of Alaska may not be sustained. From a national perspective, inclusion of all of Alaska in greenhouse gas inventory reports would ensure better accounting of the overall greenhouse gas balance of the nation and provide a foundation for considering mitigation activities in areas that are accessible enough to support substantive deployment.
More than the sum of its parts: how disturbance interactions shape forest dynamics under climate change
Authors: Lucash Melissa S. , Scheller Robert M. , Sturtevant Brian R. , Gustafson Eric J. , Kretchun Alec M. , Foster Jane R. 
Published: June 2018

AbstractInteractions among disturbances are seldom quantified, and how they will be affected by climate change is even more uncertain. In this study, we sought to better understand how interactions among disturbances shift under climate change by applying a process‐based landscape disturbance and succession model (LANDIS‐II) to project disturbance regimes under climate change in north‐central Minnesota, USA. Specifically, we (1) contrasted mortality rates and the extent of disturbance for four individual (single) disturbance regimes (fire, insects, wind, or forest management) vs. all four disturbance regimes operating simultaneously (concurrent) under multiple climate change scenarios and (2) determined how climate change interacts with single and concurrent disturbance regimes to affect carbon stocks and forest composition. Under single disturbance regimes, we found that climate change amplifies mortality, but did not substantially change the overall extent of disturbances. Tree mortality under the concurrent disturbance regime scenario was less than the sum of all single disturbance regimes, providing evidence of significant negative feedbacks among disturbances, particularly under climate change. Finally, we found that climate change was the most critical driver of area harvested (via shifts in species composition), soil carbon, species composition, and diversity, while the disturbance regime (i.e., single or concurrent) had a larger influence on aboveground carbon and the relative dominance of conifers vs. hardwoods. In conclusion, our simulations suggest that disturbance interactions will be strongly mediated by climate change and will produce increasingly negative feedbacks, preventing worst‐case disturbance outcomes. Our results underscore the importance of running simulations with multiple disturbances on the landscape concurrently rather than focusing on any one or two disturbances.
Episodic disturbances drive nutrient dynamics along freshwater‐to‐estuary gradients in a subtropical wetland
Authors: Davis Stephen E. , Boucek Ross , Castañeda‐Moya Edward , Dessu Shimelis , Gaiser Evelyn , Kominoski John , Sah Jay P. , Surratt Donatto , Troxler Tiffany 
Published: June 2018

AbstractWetlands are biogeochemically active ecosystems where primary production and respiration interact with physico‐chemical conditions to influence nutrient availability across spatio‐temporal scales. The effect of episodic disturbances on water quality dynamics within wetlands is relatively unknown, especially in large oligotrophic wetlands such as the Everglades. We describe a range of episodic disturbance events and their impacts on the spatio‐temporal dynamics of surface water total N (TN) and total P (TP) concentrations in the Everglades as a means to understand their effect and legacies. Water quality monitoring along the two principal drainages—Taylor Slough (TS) and Shark River Slough (SRS)—has been ongoing since 2000, spanning myriad disturbances ranging from high‐energy storms such as Hurricane Wilma in 2005 to a record cold event in 2010 and large fires. Local events include pulsed rainfall, low marsh stage, and stage recession and recovery (i.e., droughts and subsequent dry‐to‐wet transitions). The deposition of marine‐derived sediment from Hurricane Wilma corresponded with a doubling of TP in SRS mangrove sites (from 0.39 to 0.84 μmol/L) before recovering to pre‐disturbance mean after 5–6 yr. A brief increase in TP within one week of the 2010 cold event was followed by delayed spikes in TN (>1000 μmol/L) and TN:TP exceeding 5000 after one month. In 2008, a large fire in upper SRS prior to the wet season caused a lagged TP pulse at downstream locations SRS2, SRS3, and possibly SRS4. TP also varied negatively with depth/stage in marsh sites and positively with salinity in estuarine sites, reflecting physical concentration or dilution effects. In upper TS, TP varied according to extremes such as high rainfall and low stage relative to normal conditions. Although excess P in the Everglades is generally derived from anthropogenic upland or natural marine sources, episodic disturbance mobilizes internal sources of nutrients along an Everglades freshwater‐to‐estuary continuum, affecting water quality from days to years depending on disturbance type and intensity. The capacity for resilience is high in coastal wetland ecosystems that are exposed to high‐energy tropical storms and other episodic events, even in the highly managed Florida Everglades.
Ecotoxicity of bisphenol S to Caenorhabditis elegans by prolonged exposure in comparison with bisphenol A
Authors: Zhou Dong 
Published: June 2018

Abstract

Because of increasing concerns about its toxic effects, bisphenol A (BPA) has been gradually replaced in industrial applications by analogs such as bisphenol S (BPS). Few comparative toxicity evaluations of bisphenol analogs have been done. In the present study, 72-h exposure in L1 larvae of the model animal Caenorhabditis elegans was used to evaluate low-concentration BPS toxicity. Multiple indicators at the physiological, biochemical, and molecular levels were tested. At the physiological level, BPS exposure resulted in significantly negative effects at treatments &gt;1 µM, with head thrash being the most sensitive endpoint. At the biochemical level, BPS exposure induced no significant oxidative stress, but significantly increased apoptosis at 1 µM. At the molecular level, BPS exposure induced small but significant variations in most stress-related gene expressions at all doses. In addition, the transgenic nematode TJ375 cell line with the green fluorescent protein–based reporter hsp-16.2 was used to determine stress responses; it was found that TJ375 was not sensitive to BPS exposure. Compared with the effects of BPA shown in our previous 2016 study, the overall results showed that BPS was less noxious to C. elegans than BPA. These toxicity data for BPS could provide a foundation to evaluate the comparative toxicity of BPA alternatives. Environ Toxicol Chem 2018;37:2560–2565. © 2018 SETAC
Dissociations of cognitive inhibition, response inhibition, and emotional interference: Voxelwise ALE meta‐analyses of fMRI studies
Authors: Hung Yuwen , Gaillard Schuyler L. , Yarmak Pavel , Arsalidou Marie 
Published: June 2018

AbstractInhibitory control is the stopping of a mental process with or without intention, conceptualized as mental suppression of competing information because of limited cognitive capacity. Inhibitory control dysfunction is a core characteristic of many major psychiatric disorders. Inhibition is generally thought to involve the prefrontal cortex; however, a single inhibitory mechanism is insufficient for interpreting the heterogeneous nature of human cognition. It remains unclear whether different dimensions of inhibitory processes—specifically cognitive inhibition, response inhibition, and emotional interference—rely on dissociated neural systems. We conducted systematic meta‐analyses of fMRI studies in the BrainMap database supplemented by PubMed using whole‐brain activation likelihood estimation. A total of 66 study experiments including 1,447 participants and 987 foci revealed that while the left anterior insula was concordant in all inhibitory dimensions, cognitive inhibition reliably activated specific dorsal frontal inhibitory system, engaging dorsal anterior cingulate, dorsolateral prefrontal cortex, and parietal areas, whereas emotional interference reliably implicated a ventral inhibitory system, involving the ventral surface of the inferior frontal gyrus and the amygdala. Response inhibition showed concordant clusters in the fronto‐striatal system, including the dorsal anterior cingulate region and extended supplementary motor areas, the dorsal and ventral lateral prefrontal cortex, basal ganglia, midbrain regions, and parietal regions. We provide an empirically derived dimensional model of inhibition characterizing neural systems underlying different aspects of inhibitory mechanisms. This study offers a fundamental framework to advance current understanding of inhibition and provides new insights for future clinical research into disorders with different types of inhibition‐related dysfunctions.
Regional structural hypo‐ and hyperconnectivity of frontal–striatal and frontal–thalamic pathways in behavioral variant frontotemporal dementia
Authors: Jakabek David , Power Brian D. , Macfarlane Matthew D. , Walterfang Mark , Velakoulis Dennis , van Westen Danielle , Lätt Jimmy , Nilsson Markus , Looi Jeffrey C. L. , Santillo Alexander F. 
Published: June 2018

AbstractBehavioral variant frontotemporal dementia (bvFTD) has been predominantly considered as a frontotemporal cortical disease, with limited direct investigation of frontal–subcortical connections. We aim to characterize the grey and white matter components of frontal–thalamic and frontal–striatal circuits in bvFTD. Twenty‐four patients with bvFTD and 24 healthy controls underwent morphological and diffusion imaging. Subcortical structures were manually segmented according to published protocols. Probabilistic pathways were reconstructed separately from the dorsolateral, orbitofrontal and medial prefrontal cortex to the striatum and thalamus. Patients with bvFTD had smaller cortical and subcortical volumes, lower fractional anisotropy, and higher mean diffusivity metrics, which is consistent with disruptions in frontal–striatal–thalamic pathways. Unexpectedly, regional volumes of the striatum and thalamus connected to the medial prefrontal cortex were significantly larger in bvFTD (by 135% in the striatum, p = .032, and 217% in the thalamus, p = .004), despite smaller dorsolateral prefrontal cortex connected regional volumes (by 67% in the striatum, p = .002, and 65% in the thalamus, p = .020), and inconsistent changes in orbitofrontal cortex connected regions. These unanticipated findings may represent compensatory or maladaptive remodeling in bvFTD networks. Comparisons are made to other neuropsychiatric disorders suggesting a common mechanism of changes in frontal–subcortical networks; however, longitudinal studies are necessary to test this hypothesis.
Heat transfer in the flow of blood‐gold Carreau nanofluid induced by partial slip and buoyancy
Authors: Koriko Olubode K , Animasaun IL , Mahanthesh B , Saleem S , Sarojamma G , Sivaraj R 
Published: June 2018

AbstractDynamics of blood containing gold nanoparticles on a syringe and other objects with a nonuniform thickness is of importance to experts in the industry. This study presents the significance of partial slip (i.e. combination of linear stretching and velocity gradient) and buoyancy on the boundary layer flow of blood‐gold Carreau nanofluid over an upper horizontal surface of a paraboloid of revolution (uhspr). In this report, the viscosity of the Carreau fluid corresponding to an infinite shear‐rate is assumed as zero, meanwhile, the viscosity corresponding to zero shear‐rate, density, thermal conductivity, and heat capacity were assumed to vary with the volume fraction of nanoparticles. The governing equation that models the transport phenomenon were non‐dimensionalized and parameterized using suitable similarity variables and solved numerically using classical Runge–Kutta method with shooting techniques and MATLAB bvp4c package for validation. The results show that temperature distribution across the flow decreases more significantly with buoyancy‐related parameter when the influence of partial slip was maximized. Maximum velocity of the flow is ascertained at larger values of partial slip and buoyancy parameters. At smaller values of Deborah number and large values of volume fraction, maximum local skin friction coefficient, and local heat transfer rate are ascertained.