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Calcium glycerophosphate preserves transepithelialintegrity in the caco-2 model of intestinal transpo

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World Journal of Gastroenterology 2015年第30期21卷 9055-9066页

作者： Palika Datta and Margaret T weis Palika Datta Margaret T Weis Department of Biomedical Sciences School of Pharmacy Texas Tech University Health Sciences Center Amarillo TX 79106 United States

AIM To assess the direct effects of ischemia onintestinal epithelial integrity. Furthermore, clinicalefforts at mitigating the effect of hypoperfusion on gutpermeability have focused on restoring gut ***： we report that, in the Caco-2 cell modelof transepithelial transport, calcium glycerophosphate（CGP）, an inhibitor of intestinal alkaline phosphataseF3, has a significant effect to preserve transepithelialelectrical resistance （TEER） and to attenuate increasesin mannitol flux rates during hypoxia or ***： The effect was observable even at concentrationsas low as 1 μmol/L. As celiac disease is alsomarked by a loss of gut epithelial integrity, the effectof CGP to attenuate the effect of the α-gliadin peptide31-55 was also examined. In this instance, CGP exertedlittle effect of preservation of TEER, but significantlyattenuated peptide induced increase in mannitol ***： it appears that CGP treatment mightsynergize with other therapies to preserve gut epithelialintegrity.

关键词： Calcium glycerophosphate Gliadin peptide Intestinal permeability Intestinal ischemia Cytokine

Photoinhibition and Photoprotection in Ginkgo biloba leaves: Influence of Temperature, CO 2 and O 2 

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Acta Botanica Sinica 1999年第4期41卷 398-404页

作者：孟庆伟 Engelbert weis 邹琦赵世杰山东农业大学植物科学系

In midday ginkgo ( Ginkgo biloba L.) leaves have to bear photon flux density over 1400 μmol·m -2 ·s -1 in combination with high temperatures around 35 ℃ at natural habitat. They show typical midday depression of stomatal conductance and of CO 2 assimilation rate. The zeaxanthin changes with light intensity during the day. The influence of the combination of strong light and temperature on photoinhibition was also examined in the laboratory. A low CO 2 internal conductance (31 mmol·m -2 ·s -1 ) was found in ginkgo leaves, which had been exposed to excessive light at temperature between 15 ℃ and 35 ℃ with reduced CO 2 (80 μL·L -1 ) or oxygen (2%) for 2 h, causing a low CO 2 concentration at the carboxylation site and a high proportion of photorespiration. The ratio of electron transport to CO 2 fixation was rather high in ginkgo (16 e -/CO 2 at 25 ℃) as compared with other plants. It increased with temperature also in 2% O 2 which could not be explained solely as due to change of photorespiration. The reduction of oxygen in 340 or 80 μL·L -1 CO 2 had no effect on the extent of photoinhibition at all temperatures, which indicated that electron flow caused by photorespiration in excess light was negligible in protective effect in ginkgo leaves. However, a decreased CO 2 concentration increased photoinhibition, especially at high temperature. It is concluded that the dissipation of excessive excitation energy in the PSⅡ antennae through the xanthophyll cycle may be the major protective mechanism to preventing from the deteriorated effects of strong light in ginkgo leaves.

关键词： Photoinhibition and photoprotection Ginkgo biloba Photorespiration Xanthophyll cycle High temperature

Hepatitis C virus: Promising discoveries and new treatments

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World Journal of Gastroenterology 2016年第28期22卷 6393-6401页

作者： Juliana Cristina Santiago Bastos Marina Aiello Padilla Leonardo Cardia Caserta Noelle Miotto Aline Gonzalez Vigani Clarice weis Arns Laboratory of Virology Institute of Biology State University of Campinas - UNICAMP Internal Medicine Department Infectious Diseases division FCM-UNICAMP

Despite advances in therapy, hepatitis C virus(HCV) infection remains an important global health issue. It is estimated that a significant part of the world population is chronically infected with the virus, and many of those affected may develop cirrhosis or liver cancer. The virus shows considerable variability, a characteristic that directly interferes with disease treatment. The response to treatment varies according to HCV genotype and subtype. The continuous generation of variants(quasispecies) allows the virus to escape control by antivirals. Historically, the combination of ribavirin and interferon therapy has represented the only treatment option for the disease. Currently, several new treatment options are emerging and are available to a large part of the affected population. In addition, the search for new substances with antiviral activity against HCV continues, promising future improvements in treatment. Researchers should consider the mutation capacity of the virus and the other variables that affect treatment success.

关键词： Hepatitis C infection Hepatitis C virus Treatments Antiviral research

Observing quantum coherence from photons scattered in free-space

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Light(Science & Applications) 2021年第7期10卷 1304-1312页

作者： Shihan Sajeed thomas Jennewein Institute for Quantum Computing University of WaterlooWaterlooON N2L 3G1Canada Department of Physics and Astronomy University of WaterlooWaterlooON N2L 3G1Canada

Quantum channels in free-space,an essential prerequisite for fundamental tests of quantum mechanics and quantum technologies in open space,have so far been based on direct line-of-sight because the predominant approaches for photon-encoding,including polarization and spatial modes,are not compatible with randomly scattered *** we demonstrate a novel approach to transfer and recover quantum coherence from scattered,non-line-of-sight photons analyzed in a multimode and imaging interferometer for time-bins,combined with photon detection based on a 8×8 *** observed time-bin visibility for scattered photons remained at a high 95%over a wide scattering angle range of−45^(0) to+45^(0),while the individual pixels in the detector array resolve or track an image in its field of view of ca.0.5°.Using our method,we demonstrate the viability of two novel ***,using scattered photons as an indirect channel for quantum communication thereby enabling non-line-of-sight quantum communication with background suppression,and secondly,using the combined arrival time and quantum coherence to enhance the contrast of low-light imaging and laser ranging under high background *** believe our method will instigate new lines for research and development on applying photon coherence from scattered signals to quantum sensing,imaging,and communication in free-space environments.

关键词： scattered quantum photons

An overview of cryptographic primitives for possible use in 5G and beyond

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Science China(Information Sciences) 2020年第12期63卷 5-26页

作者： Jing YANG thomas JOHANSSON Department of Electrical and Information Technology Lund University

This survey overviews the potential use of cryptographic primitives in the fifth-generation mobile communications system(aka 5G) and beyond. It discusses the new security challenges that come with 5G and presents the upcoming security architecture. It shows the use of current cryptographic algorithms and discusses new algorithms or modifications of existing ones, that can be relevant. It also discusses the need for lightweight algorithms to meet the new use cases as well as the general demand for algorithms secure even when large quantum computers are available.

关键词： 5G cryptographic primitives lightweight cryptography post-quantum cryptography

On Markov Chains Induced by Partitioned Transition Probability Matrices

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Acta Mathematica Sinica,English Series 2011年第3期27卷 441-476页

作者： thomas KAIJSER Department of Mathematics and Information Coding Group Linkoping University S-581 83 LinkSping Sweden

Let S be a denumerable state space and let P be a transition probability matrix on S. If a denumerable set M of nonnegative matrices is such that the sum of the matrices is equal to P, then we call M a partition of P. Let K denote the set of probability vectors on S. With every partition M of P we can associate a transition probability function PM on K defined in such a way that if p ∈ K and M ∈M are such that ｜｜pM｜｜〉 0, then, with probability ｜｜pM｜｜ the vector p is transferred to the vector pM/｜｜pM｜｜. Here ｜｜·｜｜ denotes the/1-norm. In this paper we investigate the convergence in distribution for Markov chains generated by transition probability functions induced by partitions of transition probability matrices. The main motivation for this investigation is the application of the convergence results obtained to filtering processes of partially observed Markov chains with denumerable state space.

关键词： Markov chains on nonlocally compact spaces filtering processes hidden Markov chains Kantorovich metric barycenter

The reliability of age measurements for Young Stellar Objects from Hertzsprung-Russell or color-magnitude diagrams

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Research in Astronomy and Astrophysics 2012年第1期12卷 1-25页

作者： thomas Preibisch Universitts-Sternwarte Mnchen Ludwig-Maximilians-Universitt

The possibility to estimate ages and masses of Young Stellar Objects （YSOs） from their location in the Hertzsprnng-Russell diagram （HRD） or a color- magnitude diagram provides a very important tool for the investigation of fundamen- tal questions related to the processes of star formation and early stellar evolution. Age estimates are essential for studies of the temporal evolution of circumstellar material around YSOs and the conditions for planet formation. The characterization of the age distribution of the YSOs in a star forming region allows researchers to reconstruct the star formation history and provides important information on the fundamental ques- tion of whether star formation is a slow or a fast process. However, the reliability of these age measurements and the ability to detect possible age spreads in the stellar population of star forming regions are fundamentally limited by several factors. The variability of YSOs, unresolved binary components, and uncertainties in the calibra- tions of the stellar parameters cause uncertainties in the derived luminosities that are usually much larger than the typical photometry errors. Furthermore, the pre-main se- quence evolution track of a YSO depends to some degree on the initial conditions and the details of its individual accretion history. I discuss how these observational and model uncertainties affect the derived isochronal ages, and demonstrate how neglect- ing or underestimating these uncertainties can easily lead to severe misinterpretations, gross overestimates of the age spread, and ill-based conclusions about the star for- marion history. These effects are illustrated by means of Monte-Carlo simulations of observed star clusters with realistic observational uncertainties. The most important points are as follows. First, the observed scatter in the HRD must not be confused with a genuine age spread, but is always just an upper limit to the true age spread. Second, histograms of isochronal ages natural

关键词： stars: ages -- stars: pre-main sequence -- stars: formation --Hertzsprung-Russell diagram

What would a US green hydrogen energy economy look like?

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Clean Energy 2023年第5期7卷 1148-1172页

作者： thomas Tonon Independent researcher Ph.D.Aerospace and Mechanical SciencesPrinceton University1971.11 Bolfmar AvenuePrinceton JunctionNJ 08550USA

Detailed description is given for a hypothetical US hydrogen economy with solar and wind energy supplying virtually all current energy needs and with electrolytic hydrogen the energy carrier and storage *** fuels provide nonfuel products(plastics,chemicals,cement and asphalt).Only current technologies are considered and hydrogen storage accommodates generation intermit-tency and variability,using pit storage of high-pressure vessels in open air,yielding daily storage round-trip energy installation costs of 722 and 538$/kWh for electric and thermal,respectively;and for power,2351 and 2240$/kW for electric and thermal,*** long-duration storage,the costs are 94.1 and 23.8$/kWh and 937 and 845$/kW,*** energy generation 20%over baseline accommodates low-season generation,obviates much required storage and ensures that reserves are topped off;96%of US 2022 total energy consumption is provided *** the default scenario(demand energy portions:half photovoltaic,quarter on-shore wind and quarter offshore wind),the surface area for the farms(including offshore surface)requires~4.6%of the US 48-state land *** 350 pit storage sites provide both daily and long-duration storage,with the latter accounting for complete loss of generation for 4 days over a quarter of the *** pipelines and a renewed electric grid transmit and distribute *** installation cost of the public infrastructure is~$27.8 trillion for the default *** scenarios show significant in-frastructure and cost savings when batteries are used for transportation and/or utility storage,provided current insufficiencies can be ***,cost levels in money,surface and infrastructure are within existing levels already achieved in historical events and modern living.

关键词： hydrogen economy renewable energy hydrogen storage hydrogen pipelines sustainable net zero

Injector Quantum Dot Molecule Infrared Photodetector:A Concept for Efficient Carrier Injection

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Nano-Micro Letters 2011年第2期3卷 121-128页

作者： thomas Gebhard thomas Gebhard Photonics InstituteVienna University of Technology

Quantum dot infrared photodetectors are expected to be a competitive technology at high oper ation temperatures in the long and very long wavelength infrared spectral *** the fact that they already achieved notable success,the performance suffers from the thermionic emission of electrons from the quantum dots at elevated temperatures resulting in a decreasing *** order to provide an efficient carrier injection at high temperatures,quantum dot infrared photodetectors can be separated into two parts:an injection part and a detection part,so that each part can be separately *** order to integrate such functionality into a device,a new class of quantum dot infrared photodetectors using quantum dot molecules will be *** addition to a general discussion simulation results suggest a possibility to realize such a device.

关键词： Quantum dot infrared photodetector Injection Quantum dot molecule High temperature operation Responsivity