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Gloria D Elliott, Shangping Wang, Barry J Fuller
Cryopreservation has become a central technology in many areas of clinical medicine, biotechnology, and species conservation within both plant and animal biology. Cryoprotective agents (CPAs) invariably play key roles in allowing cells to be processed for storage at deep cryogenic Temperatures and to be recovered with high levels of appropriate functionality. As such, these CPA solutes possess a wide range of metabolic and biophysical effects that are both necessary for their modes of action, and potentially complicating for cell biological function...
April 18, 2017: Cryobiology
Peter NIedbalski, Christopher Parish, Andhika Kiswandhi, Zoltán Kovács, Lloyd Laporca Lumata
Dynamic nuclear polarization (DNP) via the dissolution method has alleviated the insensitivity problem in liquid-state nuclear magnetic resonance (NMR) spectroscopy by amplifying the signals by several thousand-fold. This NMR signal amplification process emanates from the microwave-mediated transfer of high electron spin alignment to the nuclear spins at high magnetic field and cryogenic temperature. Since the interplay between the electrons and nuclei is crucial, the chemical composition of a DNP sample such as the type of free radical used, glassing solvents, or the nature of the target nuclei can significantly affect the NMR signal enhancement levels that can be attained with DNP...
April 19, 2017: Journal of Physical Chemistry. A
Xiuting Chen, Qingnuan Li, Yu Gong, Lester Andrews, Benjamin K Liebov, Zongtang Fang, David A Dixon
Homoleptic thorium isocyanide complexes have been prepared via the reactions of laser-ablated thorium atoms and (CN)2 in a cryogenic matrix, and the structures of the products were characterized by infrared spectroscopy and theoretical calculations. Thorium atoms reacted with (CN)2 under UV irradiation to form the oxidative addition product Th(NC)2, which was calculated to have closed-shell singlet ground state with a bent geometry. Further reaction of Th(NC)2 and (CN)2 resulted in the formation of Th(NC)4, a molecule with a tetrahedral geometry...
April 19, 2017: Inorganic Chemistry
Katarína Bruňáková, Eva Čellárová
Beside the high post-cryogenic recovery rate, a reinstated scale of secondary metabolites in recovered plant tissues represents another inevitable aspect of an effective cryopreservation protocol for medicinal plants. The current study was aimed at evaluation of the elicitation potential of cryogenic treatment on secondary metabolism of some Hypericum species. In agreement with our assumption, the cold stimuli applied during the pre-cryogenic phase increased the tolerance to low temperatures (-196°C) in H...
April 13, 2017: Journal of Biotechnology
Aaron W Thornton, Cory M Simon, Jihan Kim, Ohmin Kwon, Kathryn S Deeg, Kristina Konstas, Steven J Pas, Matthew R Hill, David A Winkler, Maciej Haranczyk, Berend Smit
The Materials Genome is in action: the molecular codes for millions of materials have been sequenced, predictive models have been developed, and now the challenge of hydrogen storage is targeted. Renewably generated hydrogen is an attractive transportation fuel with zero carbon emissions, but its storage remains a significant challenge. Nanoporous adsorbents have shown promising physical adsorption of hydrogen approaching targeted capacities, but the scope of studies has remained limited. Here the Nanoporous Materials Genome, containing over 850 000 materials, is analyzed with a variety of computational tools to explore the limits of hydrogen storage...
April 11, 2017: Chemistry of Materials: a Publication of the American Chemical Society
Elisabetta Esposito, Rita Cortesi, Markus Drechsler, Jie Fan, Bingmei M Fu, Laura Calderan, Silvia Mannucci, Federico Boschi, Claudio Nastruzzi
Dimethyl fumarate has been demonstrated useful in relapsing remitting multiple sclerosis treatment (Tecfidera®). Nevertheless, since Tecfidera® capsules induce flushing, gastro-intestinal events and other more serious drawbacks, in this investigation a nanoparticle based system to be administered by an alternative way is proposed. In particular this study describes the preparation and characterization of dimethyl fumarate-containing solid lipid nanoparticles (SLN). Namely SLN based on tristearin, tristearin SLN treated with polysorbate 80 and cationic SLN constituted of tristearin in mixture with dimethyldioctadecylammonium chloride were investigated...
April 12, 2017: European Journal of Pharmaceutics and Biopharmaceutics
Meiying Zhang, Tongcheng Dai, Nianping Feng
Many anti-cancer drugs have a common problem of poor solubility. Increasing the solubility of the drugs is very important for its clinical applications. In the present study, we revealed that the solubility of insoluble drugs was significantly enhanced by adding rubusoside (RUB). Further, it was demonstrated that RUB could form micelles, which was well characterized by Langmuir monolayer investigation, transmission electron microscopy, atomic-force microscopy, and cryogenic transmission electron microscopy...
December 2017: Nanoscale Research Letters
Rubik Asatryan, Hayat Bennadji, Joseph William Bozzelli, Eli Ruckenstein, Lavrent Khachatryan
The fractional pyrolysis of lignin model compound para-coumaryl alcohol (p-CMA) containing a propanoid-side chain and a phenolic OH-group was studied using the System for Thermal Diagnostic Studies at temperatures 200 to 900 ºC, in order to gain mechanistic insight into the role of large substituents in high-lignin feedstocks pyrolysis. Phenol and its simple derivatives p-cresol, ethyl-, propenyl-, and propyl-phenols, were found to be the major products predominantly formed at low pyrolysis temperatures (<500oC)...
April 13, 2017: Journal of Physical Chemistry. A
Hongmin Li, Zhuang Wu, Dingqing Li, Huabin Wan, Jian Xu, Manabu Abe, Xiaoqing Zeng
The simplest alkoxycarbonylnitrene, CH3OC(O)N, has been generated through laser (266 and 193 nm) photolysis of CH3OC(O)N3 and CH3OC(O)NCO and subsequently characterized by IR ((15)N, D-labelling) and EPR (|D/hc| = 1.66 cm(-1) and |E/hc| = 0.020 cm(-1)) spectroscopy in cryogenic matrices. Two conformers of the nitrene, with the CH3 group being in syn or anti configuration to the C[double bond, length as m-dash]O bond, have been unambiguously identified. Further UV light irradiation (365 nm) of the nitrene results in isomerization to CH3ONCO, completing the frequently explored mechanism for the Curtius-rearrangement of CH3OC(O)N3...
April 13, 2017: Chemical Communications: Chem Comm
A M Kaczmarek, J Liu, B Laforce, L Vincze, K Van Hecke, R Van Deun
Here, the excellent thermal sensing capability of a multinuclear lanthanide polyoxometalate in the cryogenic region (<100 K) is presented for the first time. Up till now, no lanthanide polyoxometalates have been studied for their use as ratiometric luminescent thermometers. The investigated Tb(3+) polyoxometalate cluster is doped with 1.6% (P1) and 8.4% (P2) of Eu(3+) ions. When excited into the Mo-O charge transfer bands, at room temperature only the emission of the Eu(3+) ions is observed suggesting a very efficient energy transfer between Mo-O→Tb(3+)→Eu(3+)...
April 12, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Jennifer Patrick, Pierre Comizzoli, Gloria Elliott
The current gold standard for sperm preservation is storage at cryogenic temperatures. Dry preservation is an attractive alternative, eliminating the need for ultralow temperatures, reducing storage maintenance costs, and providing logistical flexibility for shipping. Many seeds and anhydrobiotic organisms are able to survive extended periods in a dry state through the accumulation of intracellular sugars and other osmolytes and are capable of returning to normal physiology postrehydration. Using techniques inspired by nature's adaptations, attempts have been made to dehydrate and dry preserve spermatozoa from a variety of species...
April 2017: Biopreservation and Biobanking
Mingwei Zhao, Mingwei Gao, Caili Dai, Chenwei Zou, Zhe Yang, Xuepeng Wu, Yifei Liu, Yining Wu, Sisi Fang, Wenjiao Lv
Smart wormlike micelles with stimuli-tunable rheological properties may be useful in a variety of applications, such as in molecular devices and sensors. The formation of triplestimuli-responsive systems so far has been a challenging and important issue. In this work, a novel triplestimuli (photo-, pH-, and thermoresponsive) wormlike micelle is constructed with N-cetyl-N-methylmorpholinium bromide and trans-cinnamic acid (CA). The corresponding multiresponsive behaviors of wormlike micellar system were revealed using cryogenic transmission electron microscopy, a rheometer, and (1)H NMR...
April 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Mario Hernández Vera, F A Gianturco, R Wester, H da Silva, O Dulieu, S Schiller
We present quantum calculations for the inelastic collisions between H2(+) molecules, in rotationally excited internal states, and He atoms. This work is motivated by the possibility of experiments in which the molecular ions are stored and translationally cooled in an ion trap and a He buffer gas is added for deactivation of the internal rotational population, in particular at low (cryogenic) translational temperatures. We carry out an accurate representation of the forces at play from an ab initio description of the relevant potential energy surface, with the molecular ion in its ground vibrational state, and obtain the cross sections for state-changing rotationally inelastic collisions by solving the coupled channel quantum scattering equations...
March 28, 2017: Journal of Chemical Physics
Harry Burton, Christopher Debardelaben, Wafa Amir, Thomas A Planchon
The fluorescence spectra of titanium doped sapphire (Ti:Sapphire) crystals were measured for temperature ranging from 300K to 77K. The resulting gain cross-section line shapes were calculated and used in a three-dimensional amplification model to illustrate the importance of the precise knowledge of these fluorescence spectra for the design of cryogenic cooled Ti:Sapphire based chirped-pulse laser amplifiers.
March 20, 2017: Optics Express
R S Nagymihaly, P Jojart, A Borzsonyi, K Osvay
The spectral phase noise of a cryogenically cooled Ti:Sapphire amplifier was analyzed by spectrally resolved interferometry. Since a relative phase difference measurement is performed, the effect of the amplifier stage can be determined with high precision. Contributions of the cooling system to the spectral phase noise were found to be below 50 mrad for both the vacuum pumps and the cryogenic system. The carrier-envelope phase noise of thermal and mechanical origin was also determined for different repetition rates of laser operation...
March 20, 2017: Optics Express
Simon Zeidler, Tomotada Akutsu, Yasuo Torii, Eiichi Hirose, Yoichi Aso, Raffaele Flaminio
Scattered light in inteferometric gravitational wave detectors needs to be reduced so that it will not harm the actual signals coming from a gravitational wave. In this paper, we report on the application of the theory of light scattering from mirrors in interferometric detectors having multilayer coatings on their surfaces and compared the results with single-surface scattering theories, which are traditionally used in the field of gravitational wave detectors. For the first time in this field, we have calculated the scattering distributions of the power-recycling, the signal-recycling, and the beam-splitter mirrors in KAGRA (a cryogenic interferometric gravitational wave detector currently under construction in the Kamioka mine in Japan) by using models of their multilayer coatings...
March 6, 2017: Optics Express
Dipy M Vasa, Peter L D Wildfong
Ribavirin (C8H12N4O5; anti-viral agent) was crystallized as two unique, phase-pure polymorphs (R-I and R-II). Calorimetrically determined isobaric heat capacities and heat of transition data were utilized to determine the solid-state transition temperature (Ttr), confirming enantiotropism, while R-I was determined to be kinetically stable at ambient temperature. Unprocessed samples of the low Tm polymorph, R-II, did not convert into R-I when held isothermally well above Ttr for 7days. In contrast milled R-II completely transformed to R-I after 15min at the same storage conditions, indicating that defects sustained during processing reduced the energy barrier for transformation, allowing it to occur...
April 2, 2017: International Journal of Pharmaceutics
Olga Kleinerman, Lucy Liberman, Natnael Behabtu, Matteo Pasquali, Yachin Cohen, Yeshayahu Talmon
Using direct-imaging cryogenic transmission and scanning electron microscopy, we show different stages of liquid-crystalline phase development in progressively more concentrated solutions of carbon nanotubes in chlorosulfonic acid: a dilute phase of individually dissolved carbon nanotubes; semidilute and concentrated isotropic phases; coexisting concentrated isotropic and nematic phases in local equilibrium with each other; and a fully liquid-crystalline phase. Nanometric resolution of cryogenic electron microscopy reveals carbon nanotube self-assembly into liquid-crystalline domains of several nanometers in width at very early stages...
April 13, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Terrence E Greenway, Todd S Byars, Robert B Elliot, Xixuan Jin, Matt J Griffin, David J Wise
Mortality associated with Edwardsiella ictaluri infection is a serious impediment to the commercial production of fingerling Channel Catfish Ictalurus punctatus. A patented, live, attenuated, orally delivered vaccine has been developed that offers exceptional protection against E. ictaluri infection in both laboratory and small-scale pond trials. Further vaccine development is contingent on the successful completion of large-scale field trials that accurately reflect industry conditions. This current work focuses on the validation of fermentation protocols and the optimization of downstream processing procedures to produce sufficient quantities of vaccine to conduct commercial-scale field trials...
June 2017: Journal of Aquatic Animal Health
T Grellmann, D Mayer, A Offenhäusser, R Wördenweber
Analyzing the electronic properties of individual terphenyldithiol (TPT) molecules in a temperature range of 30-300 K using cryogenic mechanically controllable break junctions, we observe an unexpected change of the transport mechanism with temperature for this linear and symmetric aromatic molecule. Whereas the work function (∼3.8 eV) and molecular energy level (∼0.8 to ∼1 eV depending on the analysis of the data) of TPT are temperature-independent, elastic tunneling dominates charge transport at low temperatures, whereby an inelastic transport (via hopping) sets in at about 100 K...
April 20, 2017: Journal of Physical Chemistry. A
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