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1.
Rasool Shumaila Cárdenas Pablo D. Pattison David I. Jensen Birgit Meyling Nicolai V. 《Journal of chemical ecology》2021,47(4-5):476-488
Journal of Chemical Ecology - Entomopathogenic fungi (EPF) can be experimentally established in several plant species as endophytes. Ecological effects of EPF inoculations on plant growth and... 相似文献
2.
Abhendra K. Singh Kaitlyn Kahle Hannah James Allison L. Horner Daniel Villaflor Zach Benedict 《Ceramics International》2021,47(12):17268-17275
In this study the effects of high temperature and moisture on the impact damage resistance and mechanical strength of Nextel 610/alumina silicate ceramic matrix composites were experimentally evaluated. Composite laminates were exposed to either a 1050°C isothermal furnace-based environment for 30 consecutive days at 6 h a day, or 95% relative humidity environment for 13 consecutive days at 67°C. Low velocity impact, tensile and short beam strength tests were performed on both ambient and environmentally conditioned laminates and damage was characterized using a combination of non-destructive and destructive techniques. High temperature and humidity environmental exposure adversely affected the impact resistance of the composite laminates. For all the environments, planar internal damage area was greater than the back side dent area, which in turn was greater than the impactor side dent area. Evidence of environmental embrittlement through a stiffer tensile response was noted for the high temperature exposed laminates while the short beam strength tests showed greater propensity for interlaminar shear failure in the moisture exposed laminates. Destructive evaluations exposed larger, more pronounced delaminations in the environmentally conditioned laminates in comparison to the ambient ones. External damage metrics of the impactor side dent depth and area directly influenced the post-impact tensile strength of the laminates while no such trend between internal damage area and residual strength could be ascertained. 相似文献
3.
Zhencai Li Dacheng Zhou Lars R. Jensen Jianbei Qiu Yanfei Zhang Yuanzheng Yue 《Journal of the American Ceramic Society》2021,104(9):4471-4478
The transparent Er3+-Yb3+-doped fluoro-aluminosilicate glass-ceramic (GC) was prepared by melt-quenching. The crystal phase, morphology, and up-conversion (UC) luminescence of as-produced GC were characterized by X-ray diffraction, scanning electron microscopy, and fluorescence spectrophotometry, respectively. The results show that BaYF5 nanocrystals were uniformly distributed in the glass matrix of the as-produced GC. When the as-produced GC was subjected to heat treatment, the crystallinity was increased, but the crystal identity remains unchanged. Such heat-treatment doubled the intensity of the UC luminescence, and this enhancement was ascribed to the increased incorporation of both Er3+ and Yb3+ ions into the lower phonon energy environment of BaYF5 nanocrystals. Furthermore, the heat-treated GC was stable against further crystallization, and consequently its UC luminescence was stable at the application temperature. The heat-treated GC was found to possess an outstanding temperature-sensing capability. 相似文献
4.
Emil Märcher Rørsted Dr. Anders A. Jensen Prof. Jesper L. Kristensen 《ChemMedChem》2021,16(21):3263-3270
4-(2-((2-hydroxybenzyl)amino)ethyl)-2,5-dimethoxybenzonitrile (25CN-NBOH) was first reported as a potent and selective serotonin 2A receptor (5-HT2AR) agonist in 2014, and it has since found extensive use as a pharmacological tool in a variety of in vitro, ex vivo and in vivo studies. 25CN-NBOH is readily available from a synthetic perspective using standard chemical transformations, and displays favorable physiochemical properties in terms of stability and solubility. Due to its superior selectivity for 5-HT2AR, 25CN-NBOH has been used to investigate the effects of selective 5-HT2AR activation in vivo, and has thus become an important pharmacological tool for the exploration of 5-HT2AR signaling in a range of animal models. In the present review, we outline the discovery of 25CN-NBOH, its pharmacological profile and major findings from studies where it has been used. 相似文献
5.
Water Resources Management - The long-term success of water service reforms depends on sufficient revenues being collected from users to allow access to be extended and quality of service to be... 相似文献
6.
Carina Heisig Jelka Diedenhoven Christopher Jensen Helmut Gehrke Thomas Turek 《化学工程与技术》2020,43(3):484-492
The conversion of bio-based succinic acid (SA) to the value-added chemicals 1,4-butanediol (BDO), γ-butyrolactone (GBL), and tetrahydrofuran (THF) can replace the corresponding petrochemical production routes to achieve a sustainable process. The reaction network for aqueous-phase catalytic hydrogenation of succinic acid over a supported Re-Pd catalyst was identified and the reaction kinetics was determined. With the developed kinetic model, the composition of the product mixture regarding the desired products (BDO, GBL, THF) can be described as a function of educt concentration, temperature, and pressure. The maximum BDO yield was achieved at high pressure and low temperature, while low pressure and high temperature favored GBL and THF production. 相似文献
7.
Rebecca Brannon Katharin Jensen Debasish Nayak 《Journal of the European Ceramic Society》2018,38(8):2971-2987
Even if a ceramic's homogenized properties (such as anisotropically evolving stiffness) truly can be predicted from complete knowledge of sub-continuum morphology (e.g., locations, sizes, shapes, orientations, and roughness of trillions of crystals, dislocations, impurities, pores, inclusions, and/or cracks), the necessary calculations are untenably hypervariate. Non-productive (almost derailing) debates over shortcomings of various first-principles ceramics theories are avoided in this work by discussing numerical coarsening in the context of a pedagogically appealing buckling foundation model that requires only sophomore-level understanding of springs, buckling hinges, dashpots, etc. Bypassing pre-requisites in constitutive modeling, this work aims to help students to understand the difference between damage and plasticity while also gaining experience in Monte-Carlo numerical optimization via scale-bridging that reduces memory and processor burden by orders of magnitude while accurately preserving aleatory (finite-sampling) perturbations that are crucial to accurately predict bifurcations, such as ceramic fragmentation. 相似文献
8.
Nicole Jacqueline Jensen Helena Zander Wodschow Malin Nilsson Jrgen Rungby 《International journal of molecular sciences》2020,21(22)
Under normal physiological conditions the brain primarily utilizes glucose for ATP generation. However, in situations where glucose is sparse, e.g., during prolonged fasting, ketone bodies become an important energy source for the brain. The brain’s utilization of ketones seems to depend mainly on the concentration in the blood, thus many dietary approaches such as ketogenic diets, ingestion of ketogenic medium-chain fatty acids or exogenous ketones, facilitate significant changes in the brain’s metabolism. Therefore, these approaches may ameliorate the energy crisis in neurodegenerative diseases, which are characterized by a deterioration of the brain’s glucose metabolism, providing a therapeutic advantage in these diseases. Most clinical studies examining the neuroprotective role of ketone bodies have been conducted in patients with Alzheimer’s disease, where brain imaging studies support the notion of enhancing brain energy metabolism with ketones. Likewise, a few studies show modest functional improvements in patients with Parkinson’s disease and cognitive benefits in patients with—or at risk of—Alzheimer’s disease after ketogenic interventions. Here, we summarize current knowledge on how ketogenic interventions support brain metabolism and discuss the therapeutic role of ketones in neurodegenerative disease, emphasizing clinical data. 相似文献
9.
Palmitoleic acid has been classified as an insulin-sensitizing lipokine, but evidence for this from human studies has been inconsistent. We hypothesized that this is related to either the types of samples or conditions under which samples are collected. We measured plasma palmitoleic acid and total free fatty acids (FFA) using ultra-performance liquid chromatography in blood samples collected from 34 adults under a variety of conditions. We collected duplicate samples of adipose (n = 10), FFA (n = 9), and very low density lipoprotein triacylglycerol (VLDL-TAG) (n = 7) to measure the palmitoleic acid as a percentage of total fatty acids. We tested whether the percentage of palmitoleic acid was correlated with insulin resistance, as measured by homeostatic model of insulin resistance (HOMA-IR). Adipose stearoyl-coenzyme A desaturase 1 (SCD-1) protein was measured by capillary Western blotting. FFA-palmitoleic acid percentage increased as a function of total FFA and was greater (p < 0.005) in females than males. Adipose palmitoleic acid percentage was greater in females than males (p < 0.001), as was adipose SCD-1. Palmitoleic acid was greater in femoral fat than in abdominal fat in both females and males (p < 0.001), and correlated positively with HOMA-IR only in females. The test–retest reliability values for percentage palmitoleic acid were 7 ± 10% for adipose, 24 ± 26% for VLDL, and 53 ± 31% for FFA. Because FFA-palmitoleic acid percentage varies as a function of total FFA, investigators should re-evaluate how palmitoleic acid data is presented. The positive relationship between adipose palmitoleic acid and HOMA-IR in females suggests that it is not a potent insulin-sensitizing lipokine in humans. 相似文献
10.
Angela M. Gutierrez Rohit Bhandari Jiaying Weng Arnold Stromberg Thomas D. Dziubla J. Zach Hilt 《应用聚合物科学杂志》2020,137(37):49109
In this work, the development of novel magnetic nanocomposite microparticles (MNMs) via free radical polymerization for their application in the remediation of contaminated water is presented. Acrylated plant-based polyphenols, curcumin multiacrylate (CMA) and quercetin multiacrylate (QMA), were incorporated as functional monomers to create high affinity binding sites for the capture of polychlorinated biphenyls (PCBs), as a model pollutant. The MNMs were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, dynamic light scattering, and UV–visible spectroscopy. The affinity of these novel materials for PCB 126 was evaluated and fitted to the nonlinear Langmuir model to determine binding affinities (KD). The results suggest the presence of the polyphenolic moieties enhances the binding affinity for PCB 126, with KD values comparable to that of antibodies. This demonstrates that these nanocomposite materials have promising potential as environmental remediation adsorbents for harmful contaminants. 相似文献