Density functional theory studies of hydrogen bonding vibrations in sI gas hydrates

Abstract To analyze the vibrational modes of water and methane in structure I gas hydrates, we constructed a 178-atom supercell with two small cages of type 512 and six large cages of type 51262. We applied the density functional theory method to simulate the vibrational spectrum and normal modes of methane hydrates. In accord with our previous studies, we confirmed that two groups of hydrogen bond (H-bond) peaks (at around 291 and 210 cm−1) in the translational bands come from two kinds of intermolecular H-bond vibrational modes. This is the first investigation of H-bond vibrations in methane hydrates. The partial modes of CH4 were extracted. We found that the CH4 phonons in the translational region are below 180 cm−1 so that the influence of methane on the H-bond is insignificant. We proposed a new method to decompose gas hydrates via direct application of terahertz radiation to the H-bonds. Herein, we confirmed that CH4 molecules do not absorb this energy.</jats:p

Neuropilin 1 sequestration by neuropathogenic mutant glycyl-tRNA synthetase is permissive to vascular homeostasis

The mechanism by which dominantly inherited mutations in the housekeeping gene GARS, which encodes glycyl-tRNA synthetase (GlyRS), mediate selective peripheral nerve toxicity resulting in Charcot-Marie-Tooth disease type 2D (CMT2D) is still largely unresolved. The transmembrane receptor protein neuropilin 1 (Nrp1) was recently identifed as an aberrant extracellular binding partner of mutant GlyRS. Formation of the Nrp1/mutant GlyRS complex antagonises Nrp1 interaction with one of its main natural ligands, vascular endothelial growth factor-A (VEGF-A), contributing to neurodegeneration. However, reduced extracellular binding of VEGF-A to Nrp1 is known to disrupt post-natal blood vessel development and growth. We therefore analysed the vascular system at early and late symptomatic time points in CMT2D mouse muscles, retina, and sciatic nerve, as well as in embryonic hindbrain. Mutant tissues show no diference in blood vessel diameter, density/growth, and branching from embryonic development to three months, spanning the duration over which numerous sensory and neuromuscular phenotypes manifest. Our fndings indicate that mutant GlyRS-mediated disruption of Nrp1/VEGF-A signalling is permissive to maturation and maintenance of the vasculature in CMT2D mice

Compensation ratio-dependent concentration of a V InH 4 complex in n-type liquid encapsulated Czochralski InP

The concentration of hydrogen-indium vacancy complex V InH 4 in liquid encapsulated Czochralski undoped and Fe-doped n-type InP has been studied by low-temperature infrared absorption spectroscopy. The V InH 4 complex is found to be a dominant intrinsic shallow donor defect with concentrations up to ∼10 16 cm -3 in as-grown liquid encapsulated Czochralski InP. The concentration of the V InH 4 complex is found to increase with the compensation ratio in good agreement with the proposed defect formation model of Walukiewicz [W. Walukiewicz, Phys. Rev. B 37, 4760 (1998); Appl. Phys. Lett. 54, 2094 (1989)], which predicts a Fermi-level-dependent concentration of amphoteric defects. © 1998 American Institute of Physics.published_or_final_versio

An optimum medium designed and verified for alcohol vinegar fermentation

In this article, a novel formula of nutrient salt for alcohol vinegar production was derived based on mass conservation theory of carbon source, nitrogen source and inorganic ions. Series of semicontinuous fermentations were successfully carried out in a Frings 10 L fermentation tank. The average acetification rate of semi-continuous fermentation was 2 g acetic acid/L*h within about 12 h, average stoichiometric yield was 94%, and then fed-batch trial for high concentration vinegar fermentation was successfully conducted. Both of these confirmed that this method applied was cost-effective. If this method is adopted in industry scale, vinegar manufacturers will reduce production cost significantly.Key words: Formula, alcohol vinegar, fermentation nutrient

Electrical and FT-IR measurements of undoped N-type INP materials grown from various stoichiometric melts

P-rich, In-rich and Stoichiometric undoped InP melts have been synthesed by phosphorus in-situ injection method. InP crystal ingots have been grown from these melts by Liquid Encapsulated Czochralski (LEC). Samples from these ingots grown from various Stoichiometric melts have been characterized by Hall Effect and Fourier Transform Infrared (FT-IR) spectroscopy measurements respectively. The Hall Effect measurement results indicate that the net carrier concentration of P-inch undoped InP is higher than that of In-rich and Stoichiometric undoped InP materials. FT-IR spectroscopy measurements reveal that there are intensive absorption peaks which have been proved to be hydrogen related indium vacancy complex V InH 4. By comparing FT-IR spectra, it is found that P-rich InP material has the most intensive absorption peak of V InH 4, while In-rich InP material has the weakest absorption peak.published_or_final_versio

Application and evaluation of a GPS multi-antenna system for dam deformation monitoring

Author name used in this publication: Yongqi Chen2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Genes Underlying Positive Influence Of Prenatal Environmental Enrichment And Negative Influence Of Prenatal Earthquake Simulation And Corrective Influence Of Chinese Herbalmedicine On Rat Offspring: Irf7 And Ninj2

Background: Prenatal environmental enrichment (EE) has been proven to positively affect but prenatal stress negatively influence the physiological and psychological processes in animals, whose trans-generational genetic mechanism remains unclearly defined. We aimed to investigate and find out key genes underlying the positive-negative effects derived from prenatal interventions.Materials and Methods: Pregnant rats were randomized into EE group (EEG), earthquake simulation group (ESG), herbal group (HG) received herbal supplements in feed after earthquake simulation, and control group (CG).Results: Light Box Defecation Test (LBDT) showed EEG offspring presented less fecal pellets than CG offspring, ESG’s more than CG’s, and HG’s less than ESG (p’s&lt;0.05). Open-field Test (OFT) score of EEG was higher than CG offspring, of ESG’s was lower than CG’s, and HG’s higher than ESG’s. Irf7 and Ninj were screened, which were up-regulated in EEG, down-regulated in ESG (FC&lt;0.5), and were neutralized in HG. Prenatal EE could positively promote the nervous system development, prenatal earthquake simulation could retard the nervous system development and Chinese herbal remedy (JKSQW) which could correct the retardation.Conclusion: The negative-positive prenatal effect could contribute to altered gene expression of Irf7 and Ninj2 which also could play a key role in the improving function of JKSQWfor the kidneys.Keywords: Prenatal stress; Earthquake simulation; Light Box Defecation Test; Open-field Test; Irf7; Ninj

Wideband Diplexer with Narrow Channel Spacing Using Hybrid Bandpass-Bandstop Structures

© 2013 IEEE. In this paper, a wideband diplexer with narrow channel spacing is designed by using hybrid bandpass-bandstop structures. Two wideband bandpass structures are designed with the transmission zeros at the upper or lower passband edges to achieve high skirt selectivity. Two bandstop structures based on half-wavelength coupled lines are integrated to the two bandpass structures to introduce additional transmission zeros and thus the skirt selectivity is further improved. Accordingly, two channel filters with high skirt selectivity and high stopband rejection are designed to realize a wideband microstrip diplexer with very narrow channel spacing. For verification, a wideband diplexer operating at 1.71-2.17 GHz and 2.30-2.70 GHz is implemented, which covers multiple frequency bands for different mobile systems. The measured results show excellent performance of passband flatness, high in-band isolation of better than 35 dB and low minimum insertion losses of 0.46 and 0.50 dB for the two channels

Broadband gradient impedance matching using an acoustic metamaterial for ultrasonic transducers

2016-2017 > Academic research: refereed > Publication in refereed journal201804_a bcmaVersion of RecordPublishe

Design of secure coding challenges for cybersecurity education in the industry

To minimize the possibility of introducing vulnerabilities in source code, software developers in the industry may attend security awareness and secure coding training. One promising novel approach to raise awareness is to use cybersecurity challenges in a capture-the-flag event. In order for this to be effective, the types of challenges must be adequately designed to address the target group. In this work we look at how to design challenges for software developers in an industrial context, based on survey given to security experts by gathering their experience on the field. While our results show that traditional methods seem to be adequate, they also reveal a new class of challenges based on code entry and interaction with an automated coach.info:eu-repo/semantics/acceptedVersio