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Characterization of three transcripts encoding small heat shock proteins expressed in the codling moth, Cydia pomonella （Lepidoptera： Tortricidae）

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Insect Science 2011年第5期18卷 473-483页

作者： Stephen F. Garczynski thomas r. Unruh Christelle Guedot Lisa G. Neven USDA-ArS Yakima Agricultural Research Laboratory Wapato Washington USA

Codling moth is a major pest of apples and pears worldwide. Increasing knowledge of how this insect responds to environmental stress will improve field and postharvest control measures used against it. The small heat shock proteins （sHsps） play a maj or role in cellular responses to environmental stressors. A degenerate oligonucleotide primer, designed against the conserved α-crystallin domain, was used in 3＇ rapid amplification of complementary DNA （cDNA） ends reactions to amplify transcripts encoding sHsps expressed in the codling moth cell line, Cp169, subjected to heat shock. Three full-length cDNAs were cloned from Cp169 cells that contained open reading frames encoding sHsps. The cDNA for CpHsp 19.8 was 795 bp encoding 177 amino acids. The cDNA for CpHsp 19.9 was 749 bp encoding 175 amino acids. The cDNA for CpHsp22.2 was 737 bp encoding 192 amino acids. Analysis of the protein sequences of the three CpHsps indicated the presence of 83 amino acids with homology to the α-crystallin domain. For each of the CpHsps, the α-crystallin domain was surrounded by divergent N- and C-terminal regions, consistent with the conserved structural features of sHsps. real-time polymerase chain reaction, used to determine the expression patterns of each of the sHsps in different developmental stages of codling moth revealed the presence of transcripts in all stages tested. Consistent with characteristics of other sHsps, expression of CpHsp transcripts were greatly enhanced when insects were subjected to heat shock. The results of this research can be used as a guide to study the roles of sHsps in codling moth control using various post-harvest treatments.

关键词： α-crystallin domain heat shock response qp.r

Appendectomy and Clostridium difficile colitis:relationships revealed by clinical observations and immunology

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World Journal of Gastroenterology 2013年第34期19卷 5607-5614页

作者： Nathan L Sanders r randal Bollinger ryan Lee Steven thomas William p.rker Dep.rtment of Surgery Duke University Medical Center

Advances in understanding the interaction between the human immune system and the microbiome have led to an improved understanding of the function of the vermiform appendix as a safe-house for beneficial bacteria in the *** advances have been made despite long standing clinical observations that the appendectomy is a safe and effective ***,more recent clinical data show that an appendectomy puts patients at increased risk for recurrent Clostridium difficile(***)-associated colitis,and probably other diseases associated with an altered *** the same time,appendectomy does not app.rently put patients at risk for an initial onset of ***-associated *** clinical observations point toward the idea that the vermiform appendix might not effectively protect the microbiome in the face of broad spectrum antibiotics,the use of which precedes the initial onset of ***-associated ***,these observations point to the idea that historically imp.rtant threats to the microbiome such as infectious gastrointestinal pathogens have been supplanted by other threats,p.rticularly the use of broad spectrum antibiotics.

关键词： Appendectomy Clostridium difficile Colitis Diarrheal illness Vermiform appendix

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 Dep.rtment 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 ap.roaches for photon-encoding,including polarization and spatial modes,are not compatible with randomly scattered *** we demonstrate a novel ap.roach 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 sup.ression,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

Content sensitivity based access control framework for Hadoop

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Digital Communications and Networks 2017年第4期3卷 213-225页

作者： Ashwin Kumar T.K. Hong Liu Johnson p. thomas Xiaofeh Hou Dep.rtment of Computer Science Oklahoma State University Stillwater OK USA

Big data technologies have seen tremendous growth in recent years. They are widely used in both industry and academia. In spite of such exponential growth, these technologies lack adequate measures to protect data from misnse/abuse. Corp.rations that collect data from multiple sources are at risk of liabilities due to the exposure of sensitive information. In the current implementation of Hadoop, only file-level access control is feasible. providing users with the ability to access data based on the attlibutes in a dataset or the user＇s role is complicated because of the sheer volume and multiple formats （structured, unstructured and semi-structured） of data. In this pap.r, we propose an access control framework, which enforces access control policies dynamically based on the sensitivity of the data. This framework enforces access control policies by harnessing the data context, usage patterns and informat/on sensitivity. Information sensitivity changes over time with the addition and removal of datasets, which can lead to modifications in access control decisions. The proposed framework accommodates these changes. The proposed framework is automated to a large extent as the data itself determines the sensitivity with minimal user intervention. Our exp.rimental results show that the proposed framework is capable of enforcing access control policies on non-multimedia datasets with minimal overhead.

关键词： Access control Data driven information sensitivity privacy Information value

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 Dep.rtment 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 p.rtitioned 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 Dep.rtment 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 p.rtition of p. Let K denote the set of probability vectors on S. With every p.rtition 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 pap.r we investigate the convergence in distribution for Markov chains generated by transition probability functions induced by p.rtitions of transition probability matrices. The main motivation for this investigation is the application of the convergence results obtained to filtering processes of p.rtially 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 imp.rtant 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 temp.ral 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 imp.rtant 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 p.rameters 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 imp.rtant 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 upp.r 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

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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 p.rtions: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 transp.rtation 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 op.r ation temp.ratures in the long and very long wavelength infrared spectral *** the fact that they already achieved notable success,the p.rformance suffers from the thermionic emission of electrons from the quantum dots at elevated temp.ratures resulting in a decreasing *** order to provide an efficient carrier injection at high temp.ratures,quantum dot infrared photodetectors can be sep.rated into two p.rts:an injection p.rt and a detection p.rt,so that each p.rt can be sep.rately *** 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 temp.rature op.ration responsivity

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