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https://www.readbyqxmd.com/read/28723348/central-serotonin-attenuates-lps-induced-systemic-inflammation
#1
Clarissa M D Mota, Caroline Rodrigues-Santos, Rodrigo A R Fernández, Ruither O G Carolino, José Antunes-Rodrigues, Janete A Anselmo-Franci, Luiz G S Branco
Serotonin (5-HT) is a neuromodulator involved in several central-mediated mechanisms, such as endocrine processes, behavior, and sleep. Dysfunction of the serotonergic system is mainly linked to psychiatric disorders, but emerging evidence suggests that immune system activation may also alter brain 5-HT signaling. However, whether central 5-HT modulates systemic inflammation (SI) remains unknown. For this purpose, male Wistar rats (280-350 g, 8-9 weeks) were submitted to the experimental protocols beginning between 9 and 10 AM with the performance of injections...
July 16, 2017: Brain, Behavior, and Immunity
https://www.readbyqxmd.com/read/28723226/improving-the-quality-and-safety-of-frozen-muscle-foods-by-emerging-freezing-technologies-a-review
#2
Ximing Zhan, Da-Wen Sun, Zhiwei Zhu, Qi-Jin Wang
Freezing is one of the most widespread used preservation methods for meats including fish meat. Traditional freezing methods such as air blast freezing and cryogenic freezing could induce some quality deterioration such as damage to cell structure, increased drip loss and poor sensory value. Therefore, novel freezing methods have been developed to minimize the disadvantages of traditional freezing methods. This review describes the enhancement of quality attributes of muscle tissues frozen by novel freezing technologies, including high pressure freezing, electrically and magnetically assisted freezing, ultrasound assisted freezing and antifreeze protein...
July 19, 2017: Critical Reviews in Food Science and Nutrition
https://www.readbyqxmd.com/read/28723156/effect-of-drying-rate-on-aerosol-particle-morphology
#3
Muhammad Bilal Altaf, Miriam Arak Freedman
The morphology of aerosol particles impacts their role in the climate system. In the submicron size regime, the morphology of particles that undergo liquid-liquid phase separation is dependent on their size, where for some systems, small particles are homogeneous and large particles are phase separated. We use cryogenic-transmission electron microscopy to probe the morphology of model organic aerosol systems. We observe that the transition region (where both homogeneous and phase separated morphologies are seen) spans 121 nm at the fastest drying rates with a midpoint diameter > 170 nm...
July 19, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28720474/nitrous-oxide-cryotherapy-for-treatment-of-esophageal-squamous-cell-neoplasia-initial-multicenter-international-experience-with-a-novel-portable-cryoballoon-ablation-system-with-video
#4
Marcia Irene Canto, Julian Abrams, Hannah Kunzli, Bas Weusten, Yoshihiro Komatsu, Blair Jobe, Charles J Lightdale
BACKGROUND AND AIMS: Early esophageal squamous cell neoplasia (ESCN) can be successfully treated by endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), or radiofrequency ablation (RFA). A new portable, battery-powered cryotherapy system using nitrous oxide (cryoballoon focal ablation system (CbFAS) has been used for Barrett's esophagus. It consists of a small hand-held device containing liquid nitrous oxide, which converts to gas within a low-pressure-compliant through-the-scope balloon and freezes targeted mucosa in contact with the balloon...
July 15, 2017: Gastrointestinal Endoscopy
https://www.readbyqxmd.com/read/28715388/measuring-the-densities-of-aqueous-glasses-at-cryogenic-temperatures
#5
Chen Shen, Ethan F Julius, Timothy J Tyree, Ritwik Dan, David W Moreau, Robert Thorne
We demonstrate a method for determining the vitreous phase cryogenic temperature densities of aqueous mixtures, and other samples that require rapid cooling, to prepare the desired cryogenic temperature phase. Microliter to picoliter size drops are cooled by projection into a liquid nitrogen-argon (N2-Ar) mixture. The cryogenic temperature phase of the drop is evaluated using a visual assay that correlates with X-ray diffraction measurements. The density of the liquid N2-Ar mixture is adjusted by adding N2 or Ar until the drop becomes neutrally buoyant...
June 28, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28714478/immobilization-of-single-argon-atoms-in-nano-cages-of-two-dimensional-zeolite-model-systems
#6
Jian-Qiang Zhong, Mengen Wang, Nusnin Akter, John D Kestell, Alejandro M Boscoboinik, Taejin Kim, Dario J Stacchiola, Deyu Lu, J Anibal Boscoboinik
The confinement of noble gases on nanostructured surfaces, in contrast to bulk materials, at non-cryogenic temperatures represents a formidable challenge. In this work, individual Ar atoms are trapped at 300 K in nano-cages consisting of (alumino)silicate hexagonal prisms forming a two-dimensional array on a planar surface. The trapping of Ar atoms is detected in situ using synchrotron-based ambient pressure X-ray photoelectron spectroscopy. The atoms remain in the cages upon heating to 400 K. The trapping and release of Ar is studied combining surface science methods and density functional theory calculations...
July 17, 2017: Nature Communications
https://www.readbyqxmd.com/read/28708395/dynamic-nuclear-polarization-of-long-lived-nuclear-spin-states-in-methyl-groups
#7
Jean-Nicolas Dumez, Basile Vuichoud, Daniele Mammoli, Aurélien Bornet, Arthur C Pinon, Gabriele Stevanato, Benno Meier, Geoffrey Bodenhausen, Sami Jannin, Malcolm H Levitt
We have induced hyperpolarized long-lived states in compounds containing 13C-bearing methyl groups by dynamic nuclear polarization (DNP) at cryogenic temperatures, followed by dissolution with a warm solvent. The hyperpolarized methyl long-lived states give rise to enhanced antiphase 13C NMR signals in solution, which often persist for times much longer than the 13C and 1H spin-lattice relaxation times under the same conditions. The DNP-induced effects are similar to quantum-rotor-induced-polarization (QRIP), but are observed in a wider range of compounds, since they do not depend critically on the height of the rotational barrier...
July 14, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28707382/neutron-crystallographic-studies-of-t4-lysozyme-at-cryogenic-temperature
#8
Le Li, Shantanu Shukla, Flora Meilleur, Robert F Standaert, Josh Pierce, Dean A A Myles, Matthew J Cuneo
Bacteriophage T4 lysozyme (T4L) has been used as a paradigm for seminal biophysical studies on protein structure, dynamics and stability. Approximately 700 mutants of this protein and their complexes have been characterized by X-ray crystallography; however, despite the high resolution diffraction limits attained in several studies, no hydrogen atoms were reported being visualized in the electron density maps. To address this, a 2.2 Å-resolution neutron data set was collected at 80 K from a crystal of perdeuterated T4L pseudo-wild type...
July 13, 2017: Protein Science: a Publication of the Protein Society
https://www.readbyqxmd.com/read/28706067/high-temperature-quantum-oscillations-caused-by-recurring-bloch-states-in-graphene-superlattices
#9
R Krishna Kumar, X Chen, G H Auton, A Mishchenko, D A Bandurin, S V Morozov, Y Cao, E Khestanova, M Ben Shalom, A V Kretinin, K S Novoselov, L Eaves, I V Grigorieva, L A Ponomarenko, V I Fal'ko, A K Geim
Cyclotron motion of charge carriers in metals and semiconductors leads to Landau quantization and magneto-oscillatory behavior in their properties. Cryogenic temperatures are usually required to observe these oscillations. We show that graphene superlattices support a different type of quantum oscillation that does not rely on Landau quantization. The oscillations are extremely robust and persist well above room temperature in magnetic fields of only a few tesla. We attribute this phenomenon to repetitive changes in the electronic structure of superlattices such that charge carriers experience effectively no magnetic field at simple fractions of the flux quantum per superlattice unit cell...
July 14, 2017: Science
https://www.readbyqxmd.com/read/28702993/gold-nanorod-induced-warming-of-embryos-from-the-cryogenic-state-enhances-viability
#10
Kanav Khosla, Yiru Wang, Mary Hagedorn, Zhenpeng Qin, John Bischof
Zebrafish embryos can attain a stable cryogenic state by microinjection of cryoprotectants followed by rapid cooling, but the massive size of the embryo has consistently led to failure during the convective warming process. Here we address this zebrafish cryopreservation problem by using gold nanorods (GNRs) to assist in the warming process. Specifically, we microinjected the cryoprotectant propylene glycol into zebrafish embryos along with GNRs, and the samples were cooled at a rate of 90 000 °C/min in liquid nitrogen...
July 13, 2017: ACS Nano
https://www.readbyqxmd.com/read/28700239/suppressing-nucleation-in-metalorganic-chemical-vapor-deposition-of-mos2-monolayers-by-alkali-metal-halides
#11
HoKwon Kim, Dmitry Ovchinnikov, Davide Deiana, Dmitrii Unuchek, Andras Kis
Towards large-area deposition of MoS2 layers, we employ metal-organic precursors of Mo and S for a facile and reproducible van der Waals epitaxy on c-plane sapphire. Exposing c-sapphire substrates to alkali metal halide salts such as KI or NaCl together with the Mo precursor prior to the start of the growth process, results in increasing the lateral dimensions of single crystalline domains by more than two orders of magnitude. The MoS2 grown this way exhibits high crystallinity and optoelectronic quality comparable to single-crystal MoS2 produced by conventional chemical vapor deposition methods...
July 12, 2017: Nano Letters
https://www.readbyqxmd.com/read/28696425/microbial-survival-strategies-in-ancient-permafrost-insights-from-metagenomics
#12
Rachel Mackelprang, Alexander Burkert, Monica Haw, Tara Mahendrarajah, Christopher H Conaway, Thomas A Douglas, Mark P Waldrop
In permafrost (perennially frozen ground) microbes survive oligotrophic conditions, sub-zero temperatures, low water availability and high salinity over millennia. Viable life exists in permafrost tens of thousands of years old but we know little about the metabolic and physiological adaptations to the challenges presented by life in frozen ground over geologic time. In this study we asked whether increasing age and the associated stressors drive adaptive changes in community composition and function. We conducted deep metagenomic and 16 S rRNA gene sequencing across a Pleistocene permafrost chronosequence from 19 000 to 33 000 years before present (kyr)...
July 11, 2017: ISME Journal
https://www.readbyqxmd.com/read/28695200/room-temperature-high-detectivity-mid-infrared-photodetectors-based-on-black-arsenic-phosphorus
#13
Mingsheng Long, Anyuan Gao, Peng Wang, Hui Xia, Claudia Ott, Chen Pan, Yajun Fu, Erfu Liu, Xiaoshuang Chen, Wei Lu, Tom Nilges, Jianbin Xu, Xiaomu Wang, Weida Hu, Feng Miao
The mid-infrared (MIR) spectral range, pertaining to important applications, such as molecular "fingerprint" imaging, remote sensing, free space telecommunication, and optical radar, is of particular scientific interest and technological importance. However, state-of-the-art materials for MIR detection are limited by intrinsic noise and inconvenient fabrication processes, resulting in high-cost photodetectors requiring cryogenic operation. We report black arsenic phosphorus-based long-wavelength IR photodetectors, with room temperature operation up to 8...
June 2017: Science Advances
https://www.readbyqxmd.com/read/28689658/conformational-landscape-of-the-p28-bound-human-proteasome-regulatory-particle
#14
Ying Lu, Jiayi Wu, Yuanchen Dong, Shuobing Chen, Shuangwu Sun, Yong-Bei Ma, Qi Ouyang, Daniel Finley, Marc W Kirschner, Youdong Mao
The proteasome holoenzyme is activated by its regulatory particle (RP) consisting of two subcomplexes, the lid and the base. A key event in base assembly is the formation of a heterohexameric ring of AAA-ATPases, which is guided by at least four RP assembly chaperones in mammals: PAAF1, p28/gankyrin, p27/PSMD9, and S5b. Using cryogenic electron microscopy, we analyzed the non-AAA structure of the p28-bound human RP at 4.5 Å resolution and determined seven distinct conformations of the Rpn1-p28-AAA subcomplex within the p28-bound RP at subnanometer resolutions...
June 26, 2017: Molecular Cell
https://www.readbyqxmd.com/read/28688446/slow-photoelectron-velocity-map-imaging-of-cold-tert-butyl-peroxide
#15
Jessalyn A DeVine, Marissa L Weichman, Mark C Babin, Daniel M Neumark
Photoelectron spectra of cryogenically cooled X∼(1)A' tert-butyl peroxide anions are obtained using slow electron velocity-map imaging. The spectra show highly structured bands corresponding to detachment to the X∼(2)A″ and A∼(2)A(') electronic states of the neutral radical and represent a notable improvement in resolution over previous photoelectron spectra. We report an electron affinity of 1.1962(20) eV and a term energy T0(A∼(2)A(')) of 0.9602(24) eV for the tert-butyl peroxy radical. New vibrational structure is resolved, providing several frequencies for both neutral states...
July 7, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28688412/conformation-selective-resonant-photoelectron-imaging-from-dipole-bound-states-of-cold-3-hydroxyphenoxide
#16
Guo-Zhu Zhu, Dao-Ling Huang, Lai-Sheng Wang
We report a photoelectron imaging and photodetachment study of cryogenically cooled 3-hydroxyphenoxide (3HOP) anions, m-HO(C6H4)O(-). In a previous preliminary study, two conformations of the cold 3HOP anions with different dipole bound states were observed [D. L. Huang et al., J. Phys. Chem. Lett. 6, 2153 (2015)]. Five near-threshold vibrational resonances were revealed in the photodetachment spectrum from the dipole-bound excited states of the two conformations. Here, we report a more extensive investigation of the two conformers with observation of thirty above-threshold vibrational resonances in a wide spectral range between 18 850 and 19 920 cm(-1) (∼1000 cm(-1) above the detachment thresholds)...
July 7, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28682616/vibrational-characterization-of-microsolvated-electrocatalytic-water-oxidation-intermediate-ru-tpy-bpy-oh-2-h2o-0-4
#17
Erin M Duffy, Jonathan M Voss, Etienne Garand
The infrared predissociation spectra of the mass-selected electrocatalytic water oxidation intermediate [Ru(tpy)(bpy)(OH)](2+)(H2O)0-4 are reported. The [Ru(tpy)(bpy)(OH)](2+) species is generated by passing a solution of [Ru(tpy)(bpy)(H2O)](ClO4)2 through an electrochemical flow cell held at 1.2 V and is immediately introduced into the gas phase via electrospray ionization (ESI). The microsolvated clusters are formed by reconstructing the water network in a cryogenic ion trap. Details of the hydrogen bonding network in these clusters are revealed by the infrared predissociation spectra in the OH stretch region...
July 17, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28678828/a-technique-for-lyopreservation-of-clostridium-ljungdahlii-in-a-biocomposite-matrix-for-co-absorption
#18
Mark J Schulte, Jason Solocinski, Mian Wang, Michelle Kovacs, Ryan Kilgore, Quinn Osgood, Lukas Underwood, Michael C Flickinger, Nilay Chakraborty
A system capable of biocatalytic conversion of distributed sources of single carbon gases such as carbon monoxide into hydrocarbons can be highly beneficial for developing commercially viable biotechnology applications in alternative energy. Several anaerobic bacterial strains can be used for such conversion. The anaerobic carbon monoxide-fixing bacteria Clostridium ljungdahlii OTA1 is a model CO assimilating microorganism that currently requires cryogenic temperature for storage of the viable strains. If these organisms can be stabilized and concentrated in thin films in advanced porous materials, it will enable development of high gas fraction, biocomposite absorbers with elevated carbon monoxide (CO) mass transfer rate, that require minimal power input and liquid, and demonstrate elevated substrate consumption rate compared to conventional suspended cell bioreactors...
2017: PloS One
https://www.readbyqxmd.com/read/28678483/hydrogen-sulfide-capture-from-absorption-in-polar-liquids-to-oxide-zeolite-and-metal-organic-framework-adsorbents-and-membranes
#19
Mansi S Shah, Michael Tsapatsis, J Ilja Siepmann
Hydrogen sulfide removal is a long-standing economic and environmental challenge faced by the oil and gas industries. H2S separation processes using reactive and non-reactive absorption and adsorption, membranes, and cryogenic distillation are reviewed. A detailed discussion is presented on new developments in adsorbents, such as ionic liquids, metal oxides, metals, metal-organic frameworks, zeolites, carbon-based materials, and composite materials; and membrane technologies for H2S removal. This Review attempts to exhaustively compile the existing literature on sour gas sweetening and to identify promising areas for future developments in the field...
July 5, 2017: Chemical Reviews
https://www.readbyqxmd.com/read/28674417/serial-femtosecond-crystallography-structure-of-cytochrome-c-oxidase-at-room-temperature
#20
Rebecka Andersson, Cecilia Safari, Robert Dods, Eriko Nango, Rie Tanaka, Ayumi Yamashita, Takanori Nakane, Kensuke Tono, Yasumasa Joti, Petra Båth, Elin Dunevall, Robert Bosman, Osamu Nureki, So Iwata, Richard Neutze, Gisela Brändén
Cytochrome c oxidase catalyses the reduction of molecular oxygen to water while the energy released in this process is used to pump protons across a biological membrane. Although an extremely well-studied biological system, the molecular mechanism of proton pumping by cytochrome c oxidase is still not understood. Here we report a method to produce large quantities of highly diffracting microcrystals of ba 3-type cytochrome c oxidase from Thermus thermophilus suitable for serial femtosecond crystallography. The room-temperature structure of cytochrome c oxidase is solved to 2...
July 3, 2017: Scientific Reports
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