68,269 results match your criteria experiments including


Commodity plastic burning as a source of inhaled toxic aerosols.

J Hazard Mater 2021 Apr 8;416:125820. Epub 2021 Apr 8.

Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China.

Commodity plastic is ubiquitous in daily life and commonly disposed of via unregulated burning, particularly in developing regions. We report here the much higher emission factors (13.1 ± 7. Read More

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Investigation of the effects of two major secretory granules components, insulin and zinc, on human-IAPP amyloid aggregation and membrane damage.

Chem Phys Lipids 2021 Apr 19:105083. Epub 2021 Apr 19.

Biophysics Program, Department of Chemistry, Biomedical Engineering, and Macromolecular Science and Engineering, The University of Michigan, Ann Arbor, MI 48109-1055, USA. Electronic address:

Human islet amyloid polypeptide (hIAPP) is a highly amyloidogenic peptide found in pancreatic islets of type-2 diabetes (T2D) patients. Under certain conditions, hIAPP is able to form amyloid fibrils that play a role in the progression of T2D. hIAPP is synthesized in the β-cell of the pancreas and stored in the secretory granules before being released into the extracellular compartment. Read More

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A mutation of the β-domain in POU1F1 causes pituitary deficiency due to dominant PIT-1β expression.

Eur J Endocrinol 2021 Apr 1. Epub 2021 Apr 1.

H Azuma, Department of Pediatrics, Asahikawa Medical University, Asahikawa, Japan.

Background: POU1F1 encodes both PIT-1α, which plays pivotal roles in pituitary development and GH, PRL and TSHB expression, and the alternatively spliced isoform PIT-1β, which contains an insertion of 26-amino acids (β-domain) in the transactivation domain of PIT-1α due to the use of an alternative splice acceptor at the end of the first intron. PIT-1β is expressed at much lower levels than PIT-1α and represses endogenous PIT-1α transcriptional activity. Although POU1F1 mutations lead to combined pituitary hormone deficiency (CPHD), no patients with β-domain mutations have been reported. Read More

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Explicit Facial Expression Transfer via Fine-Grained Representations.

IEEE Trans Image Process 2021 Apr 22;PP. Epub 2021 Apr 22.

Facial expression transfer between two unpaired images is a challenging problem, as fine-grained expression is typically tangled with other facial attributes. Most existing methods treat expression transfer as an application of expression manipulation, and use predicted global expression, landmarks or action units (AUs) as a guidance. However, the prediction may be inaccurate, which limits the performance of transferring fine-grained expression. Read More

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The Effect of Dissolved Natural Organic Matter on Adsorption of Phenolic Compounds on Suspended Sediments.

Environ Technol 2021 Apr 22:1-23. Epub 2021 Apr 22.

School of Water and Environment, Chang'an University, Xi'an 710054, China.

Phenolic compounds have caused different degrees of negative impacts in aquatic environment. Amino acids, humic acids and carbohydrates are the three dominant types of dissolved natural organic matter (DNOM) in natural water bodies. In this research, the influences of dissolved natural organic matter (DNOM) on the adsorption behaviors of phenol, 2,4-dichlorophenol (DCP) and 2,4,6-trichlorophenol (TCP) in Weihe River suspended sediment were studied by using DL-alanine, fulvic acid and glucose as the representatives of the three types of DNOM. Read More

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Atmospheric Fate of a New Polyfluoroalkyl Building Block, CFOCHFCFSCHCHOH.

Environ Sci Technol 2021 Apr 22. Epub 2021 Apr 22.

Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada.

Many per- and polyfluoroalkyl substances (PFAS) have been regulated or phased-out of usage due to concerns about persistence, bioaccumulation potential, and toxicity. We investigated the atmospheric fate of a new polyfluorinated alcohol 2-(1,1,2-trifluoro-2-heptafluoropropyloxy-ethylsulfanyl)-ethanol (CFOCHFCFSCHCHOH, abbreviated FESOH) by assessing the kinetics and products of the gas-phase reaction of FESOH with chlorine atoms and hydroxyl radicals. Experiments performed in a stainless-steel chamber interfaced to an FTIR were used to determine reaction kinetics and gas-phase products. Read More

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Mechanistic Understanding of Water Oxidation in the Presence of a Copper Complex by Electrochemical Liquid Transmission Electron Microscopy.

ACS Appl Mater Interfaces 2021 Apr 22. Epub 2021 Apr 22.

Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 45137-66731 Zanjan, Iran.

The design of molecular oxygen-evolution reaction (OER) catalysts requires fundamental mechanistic studies on their widely unknown mechanisms of action. To this end, copper complexes keep attracting interest as good catalysts for the OER, and metal complexes with TMC (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) stand out as active OER catalysts. A mononuclear copper complex, [Cu(TMC)(HO)](NO) (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), combined both key features and was previously reported to be one of the most active copper-complex-based catalysts for electrocatalytic OER in neutral aqueous solutions. Read More

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Self-healing and anti-freezing graphene-hydrogel-graphene sandwich strain sensor with ultrahigh sensitivity.

J Mater Chem B 2021 Apr 23;9(13):3088-3096. Epub 2021 Mar 23.

Department of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P. R. China.

Hydrogels with specially designed structures and adjustable properties have been considered as smart materials with multi-purpose application prospects, especially in the field of flexible sensors. However, most hydrogel-based sensors have low sensitivity, which inevitably affects their promotion in the market. Herein, a strain sensor comprising a poly(vinyl alcohol)/poly(acrylic acid) (PVA/PAA) hybrid hydrogel sandwiched between two graphene layers was successfully constructed in a facile way, and it exhibited many excellent properties including extremely high sensitivity. Read More

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Structure and Interactions in Perfluorooctanoate Micellar Solutions Revealed by Small-Angle Neutron Scattering and Molecular Dynamics Simulations Studies: Effect of Urea.

Langmuir 2021 Apr 22. Epub 2021 Apr 22.

Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York (SUNY), Buffalo, New York 14260-4200, United States.

The self-assembly of surfactants in aqueous solution can be modulated by the presence of additives including urea, which is a well-known protein denaturant and also present in physiological fluids and agricultural runoff. This study addresses the effects of urea on the structure of micelles formed in water by the fluorinated surfactant perfluoro--octanoic acid ammonium salt (PFOA). Analysis of small-angle neutron scattering (SANS) experiments and atomistic molecular dynamics (MD) simulations provide consensus strong evidence for the direct mechanism of urea action on micellization: urea helps solvate the hydrophobic micelle core by localizing at the surface of the core in the place of some water molecules. Read More

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Structure Determination, Biosynthetic Origin, and Total Synthesis of Akazaoxime, an Enteromycin-Class Metabolite from a Marine-Derived Actinomycete of the Genus .

J Org Chem 2021 Apr 22. Epub 2021 Apr 22.

Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.

A new enteromycin-class antibiotic, akazaoxime (), possessing an aldoxime functionality in place of -methyl nitronic acid, was isolated from the cultured extract of a marine-derived actinomycete of the genus , along with known A-76356 (). The structure of , including the absolute stereochemistry of three chiral centers, was established by comprehensive analysis of nuclear magnetic resonance (NMR) and mass spectrometry data coupled with magnetic anisotropy analysis of its phenylglycine methyl ester derivatives. The stereochemistry of , not determined previously, was proven to be the same as that of on the basis of the similarity of their NMR and specific rotation data. Read More

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The multiple functions of actin in apicomplexan parasites.

Cell Microbiol 2021 Apr 22:e13345. Epub 2021 Apr 22.

Faculty of Veterinary Medicine, Experimental Parasitology, Ludwig Maximilian University, Munich, Germany.

The cytoskeletal protein actin is highly abundant and conserved in eukaryotic cells. It occurs in two different states- the globular (G-actin) form, which can polymerise into the filamentous (F-actin) form, fulfilling various critical functions including cytokinesis, cargo trafficking and cellular motility. In higher eukaryotes there are several actin isoforms with nearly identical amino acid sequences. Read More

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Enhancing the analysis of disorder in X-ray absorption spectra: application of deep neural networks to T-jump-X-ray probe experiments.

Phys Chem Chem Phys 2021 Apr;23(15):9259-9269

Chemistry - School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.

Many chemical and biological reactions, including ligand exchange processes, require thermal energy for the reactants to overcome a transition barrier and reach the product state. Temperature-jump (T-jump) spectroscopy uses a near-infrared (NIR) pulse to rapidly heat a sample, offering an approach for triggering these processes and directly accessing thermally-activated pathways. However, thermal activation inherently increases the disorder of the system under study and, as a consequence, can make quantitative interpretations of structural changes challenging. Read More

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Greenhouse gas fluxes from turfgrass systems: Species, growth rate, clipping management, and environmental effects.

J Environ Qual 2021 Mar 31. Epub 2021 Mar 31.

Dep. of Horticulture and Landscape Architecture, Purdue Univ., West Lafayette, IN, 47907, USA.

Turfgrass systems can be an important source or sink for greenhouse gases (GHG), including carbon dioxide (CO ), nitrous oxide (N O), and methane (CH ). Further research is required in turfgrass systems; therefore, our objectives were to evaluate the effects of turfgrass species, growth rate, clipping management, and environmental conditions on GHG emissions. Greenhouse gas fluxes were measured in two separate field experiments in West Lafayette, IN. Read More

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Rethinking the McGurk effect as a perceptual illusion.

Atten Percept Psychophys 2021 Apr 21. Epub 2021 Apr 21.

Department of Psychological and Brain Sciences, Villanova University, Villanova, PA, USA.

Visual speech cues play an important role in speech recognition, and the McGurk effect is a classic demonstration of this. In the original McGurk & Macdonald (Nature 264, 746-748 1976) experiment, 98% of participants reported an illusory "fusion" percept of /d/ when listening to the spoken syllable /b/ and watching the visual speech movements for /g/. However, more recent work shows that subject and task differences influence the proportion of fusion responses. Read More

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Using Virtual Simulations in Online Laboratory Instruction and Active Learning Exercises as a Response to Instructional Challenges during COVID-19.

Authors:
Kanwal S Alvarez

J Microbiol Biol Educ 2021 31;22(1). Epub 2021 Mar 31.

Culver-Stockton College, Canton, MO 63435.

The onset of the COVID-19 pandemic in the spring of 2020 thrust instructors into a world of frenzy, presenting unique challenges to delivering course content. A particular challenge was determining suitable substitutes for wet lab experiments that are often comprised in science labs. Recognizing that this problem was not short-term, I started to look into virtual substitutions to be implemented in the 2020-2021 academic year. Read More

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Cholinergic Modulation of General Anesthesia.

Curr Neuropharmacol 2021 Apr 20. Epub 2021 Apr 20.

Department of Anesthesia, Peking University, Shenzhen, China.

Acetylcholine in the brain serves arousal and cognitive functions. Cholinergic neurons in the mesopontine brainstem and basal forebrain are important for activation of the cerebral cortex, which is characterized by suppression of irregular slow waves and increase in gamma (30-100 Hz) activity in the electroencephalogram, and appearance of a hippocampal theta rhythm. During general anesthesia, decrease in acetylcholine release and cholinergic functions contribute to the desirable outcomes of general anesthesia such as amnesia, loss of awareness and consciousness, and immobility. Read More

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Multiple dimensions of social motivation in adult female degus.

PLoS One 2021 21;16(4):e0250219. Epub 2021 Apr 21.

Department of Psychology, University of Montana, Missoula, Montana, United States of America.

Many animals become more motivated to interact after a period of isolation. This phenomenon may involve general drives, e.g. Read More

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Single-Site vs Cluster Catalysis in High Temperature Oxidations.

Angew Chem Int Ed Engl 2021 Apr 21. Epub 2021 Apr 21.

Instituto de Tecnologia Quimica, Catalysis, SPAIN.

The behavior of single Pt atoms and small Pt clusters for high temperature oxidation reactions has been investigated using CHA zeolite. Subtle changes in the atomic structure of the active sites are responsible for drastic changes in performance driven by specific interactions between the metal, the gas-phase components, and the support - in our case, a well-defined, non-reducible macro-ligand. The high-stability of these molecular sites in CHA is a key to intrinsic structure-performance descriptions of elemental steps such as O2 dissociation, and subsequent oxidation catalysis of industrial interest, such as the combustion of methane, propane, and CO. Read More

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Suspect screening and targeted analysis of acyl coenzyme A thioesters in bacterial cultures using a high-resolution tribrid mass spectrometer.

Anal Bioanal Chem 2021 Apr 21. Epub 2021 Apr 21.

Organic Geochemistry, Carl von Ossietzky University Oldenburg, 26129, Oldenburg, Germany.

Analysis of acyl coenzyme A thioesters (acyl-CoAs) is crucial in the investigation of a wide range of biochemical reactions and paves the way to fully understand the concerned metabolic pathways and their superimposed networks. We developed two methods for suspect screening of acyl-CoAs in bacterial cultures using a high-resolution Orbitrap Fusion tribrid mass spectrometer. The methods rely on specific fragmentation patterns of the target compounds, which originate from the coenzyme A moiety. Read More

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Creating and controlling visual environments using BonVision.

Elife 2021 Apr 21;10. Epub 2021 Apr 21.

Experimental Psychology, University College London, London, United Kingdom.

Real-time rendering of closed-loop visual environments is important for next-generation understanding of brain function and behaviour, but is often prohibitively difficult for non-experts to implement and is limited to few laboratories worldwide. We developed BonVision as an easy-to-use open-source software for the display of virtual or augmented reality, as well as standard visual stimuli. BonVision has been tested on humans and mice, and is capable of supporting new experimental designs in other animal models of vision. Read More

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hsa‑miR‑5580‑3p inhibits oral cancer cell viability, proliferation and migration by suppressing LAMC2.

Mol Med Rep 2021 Jun 21;23(6). Epub 2021 Apr 21.

Department of Gastroenterology, Puai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430033, P.R. China.

The present study aimed to explore whether and how microRNA‑5580‑3p (miR‑5580‑3p) affected oral cancer (OC) cell phenotypes via regulation of laminin subunit γ2 (LAMC2). Bioinformatics analysis was used to identify miR‑5580‑3p/LAMC2, a novel interactome that, to the best of our knowledge, has not been studied previously in OC. In the present study, the expression levels of miR‑5580‑3p and LAMC2 were detected by reverse transcription‑quantitative PCR, while the protein expression levels of LAMC2 were identified using western blotting. Read More

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IL-17A secreted by Th17 cells is essential for the host against infections.

J Microbiol Biotechnol 2021 Apr 21. Epub 2021 Apr 21.

College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing 163319, P.R. China.

is an important bacterial pathogen that is the causative agent of diseases, including neonatal sepsis and meningitis, and infections in pregnant women and non-pregnant adults. Although antibiotic treatments effectively relieve symptoms, the emergence and transmission of multidrug-resistant strains indicate the need for an effective immunotherapy. Effector T helper (Th) 17 cells is a relatively newly discovered subpopulation of helper CD4 T lymphocytes, by expressing interleukin (IL)-17A play crucial roles in host defenses against a variety of pathogens, including bacteria and viruses. Read More

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High-dimensional single cell mass cytometry analysis of the murine hematopoietic system reveals signatures induced by ageing and physiological pathogen challenges.

Immun Ageing 2021 Apr 20;18(1):20. Epub 2021 Apr 20.

Regenerative Immunology and Aging, BIH Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany.

Background: Immune ageing is a result of repetitive microbial challenges along with cell intrinsic or systemic changes occurring during ageing. Mice under 'specific-pathogen-free' (SPF) conditions are frequently used to assess immune ageing in long-term experiments. However, physiological pathogenic challenges are reduced in SPF mice. Read More

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SCD leads to the development and progression of acute myocardial infarction through the AMPK signaling pathway.

BMC Cardiovasc Disord 2021 Apr 20;21(1):197. Epub 2021 Apr 20.

Department of General Practice, The Second Affiliated Hospital of Shenyang Medical College, Shenyang, China.

Background: Acute myocardial infarction (AMI) is myocardial necrosis caused by acute coronary ischemia and hypoxia. It can be complicated by arrhythmia, shock, heart failure and other symptoms that can be life-threatening. A multi-regulator driven dysfunction module for AMI was constructed. Read More

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Early detection of Alzheimer's disease using creatine chemical exchange saturation transfer magnetic resonance imaging.

Neuroimage 2021 Apr 17:118071. Epub 2021 Apr 17.

F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, MD, USA; Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address:

Detecting Alzheimer's disease (AD) at an early stage brings a lot of benefits including disease management and actions to slow the progression of the disease. Here, we demonstrate that reduced creatine chemical exchange saturation transfer (CrCEST) contrast has the potential to serve as a new biomarker for early detection of AD. The results on wild type (WT) mice and two age-matched AD models, namely tauopathy (Tau) and Aβ amyloidosis (APP), indicated that CrCEST contrasts of the cortex and corpus callosum in the APP and Tau mice were significantly reduced compared to WT counterpart at an early stage (6-7 months) (p<0. Read More

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Poisson noisy image restoration via overlapping group sparse and nonconvex second-order total variation priors.

PLoS One 2021 20;16(4):e0250260. Epub 2021 Apr 20.

Key Laboratory for Applied Statistics of MOE, School of Mathematics and Statistics, Northeast Normal University, Changchun, P.R. China.

The restoration of the Poisson noisy images is an essential task in many imaging applications due to the uncertainty of the number of discrete particles incident on the image sensor. In this paper, we consider utilizing a hybrid regularizer for Poisson noisy image restoration. The proposed regularizer, which combines the overlapping group sparse (OGS) total variation with the high-order nonconvex total variation, can alleviate the staircase artifacts while preserving the original sharp edges. Read More

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Adaptive Neural Network Fixed-Time Control Design for Bilateral Teleoperation With Time Delay.

IEEE Trans Cybern 2021 Apr 20;PP. Epub 2021 Apr 20.

In this article, subject to time-varying delay and uncertainties in dynamics, we propose a novel adaptive fixed-time control strategy for a class of nonlinear bilateral teleoperation systems. First, an adaptive control scheme is applied to estimate the upper bound of delay, which can resolve the predicament that delay has significant impacts on the stability of bilateral teleoperation systems. Then, radial basis function neural networks (RBFNNs) are utilized for estimating uncertainties in bilateral teleoperation systems, including dynamics, operator, and environmental models. Read More

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A Framework for Hexagonal Image Processing Using Hexagonal Pixel-Perfect Approximations in Subpixel Resolution.

IEEE Trans Image Process 2021 Apr 20;PP. Epub 2021 Apr 20.

Image processing in hexagonal lattice has many advantages rather than square lattice. Researchers have addressed benefits of hexagonal structure in applications such as binarization, rotation, scaling and edge detection. Approximately all existing hardwares for capturing and displaying images are based on square lattice. Read More

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MonoGRNet: A General Framework for Monocular 3D Object Detection.

IEEE Trans Pattern Anal Mach Intell 2021 Apr 20;PP. Epub 2021 Apr 20.

Detecting and localizing objects in the real 3D space, which plays a crucial role in scene understanding, is particularly challenging given only a monocular image due to the geometric information loss during imagery projection. We propose MonoGRNet for the amodal 3D object detection from a monocular image via geometric reasoning in both the observed 2D projection and the unobserved depth dimension. MonoGRNet decomposes the monocular 3D object detection task into four sub-tasks including 2D object detection, instance-level depth estimation, projected 3D center estimation and local corner regression. Read More

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