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selection and design of high affinity DNA ligands for mutant single-chain derivatives of the bacteriophage 434 repressor

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science China(Life sciences) 2001年第3期44卷 274-286页

作者：梁铁兵谭克辉种康朱至清 sándorPongor andrássimoncsits 1. Institute of Botany Chinese Academy of Sciences 100093 Beijing China 2. ICGEB 34012 Trieste Italy

single-chain repressor RRTREs is a derivative of bacteriophage 434 repressor, which contains covalently dimerized DNA-binding domains (amino acids 1-69) of the phage 434 repressor. In this single-chain molecule, the wild type domain R is connected to the mutant domain RTREs by a recombinant linker in a head-to-tail arrangement. The DNA-contacting amino acids of RTREs at the -1, 1,2, and 5 positions of the α3 helix are T, R, E, s respectively. By using a randomized DNA pool containing the central sequence -CATACAAGAAAGNNNNNNTTT-. a cyclic, in vitro DNA-binding site selection was performed. The selected population was cloned and the individual members were characterized by determining their binding affinities to RRTREs. The results showed that the optimal operators contained the TTAC or TTCC sequences in the underlined positions as above, and that the Kd values were in the 1×10-12mol/L1×10-11mol/L concentration range. since the affinity of the natural 434 repressor to its natural operator sites is in the 1×10-9 mol/L range, the observed binding affinity increase is remarkable. It was also found that binding affinity was strongly affected by the flanking bases of the optimal tetramer binding sites, especially by the base at the 5' position. We constructed a new homodimeric single-chain repressor RrREsRtREs and its DNA-binding specificity was tested by using a series of new operators designed according to the recognition properties previously determined for the RTREs domain. These operators containing the consensus sequence GTAAGAAARNTTACN or GGAAGAAARNTTCCN (R is A or G) were recognized by RTREsRTREs specifically, and with high binding affinity. Thus, by using a combination of random selection and rational design principles, we have discovered novel, high affinity protein-DNA interactions with new specificity. This method can potentially be used to obtain new binding specificity for other DNA-binding proteins.

关键词： binding site selection bacteriophage 434 repressor single-chain repressor protein-DNA interaction protein engineering.

Fintech platforms:Lax or careful borrowers’screening?

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Financial Innovation 2021年第1期7卷 1301-1333页

作者： serena gallo University of Campania Luigi Vanvitelli CapuaItaly University of Naples Parthenope NaplesItaly

Can peer-to-peer lending platforms mitigate fraudulent behaviors?Or have lending players been acting similar to free-riders?This paper constructs a new proxy to investigate lending platform misconduct and compares the FICO score and the LendingClub credit *** examine whether the lack of verification by the Fintech platform affects lenders’collection performance,I explore the recovery rate(RR)of non-performing loans through a mixed-continuous *** regression results show that the degree of prudence taken by the lending platform in the pre-screening activity negatively affects the detection of some misreporting borrowers.I also find that the Fintech platform’s missing verification information(e.g.,annual income and employment length)affects the RR of non-performing loans,thereby hampering lenders’collection performance.

关键词： Peer to peer lending Credit grade Misreporting Misconduct Recovery rate

Improved shape hardening function for bounding surface model for cohesive soils

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 328-337页

作者： andrés Nieto-Leal Victor N.Kaliakin Department of Civil & Environmental Engineering University of Delaware Newark DE 19716 USA Department of Civil Engineering Universidad Militar Nueva Granada Bogotá Colombia

A shape hardening function is developed that improves the predictive capabilities of the generalized bounding surface model for cohesive soils, especially when applied to overconsolidated specimens. This improvement is realized without any changes to the simple elliptical shape of the bounding surface, and actually reduces the number of parameters associated with the model by one.

关键词： Constitutive model Bounding surface plasticity shape hardening function Clay

The immune hunger games:the effects of fasting on monocytes

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Cellular & Molecular Immunology 2023年第10期20卷 1098-1100页

作者： Jorge Domínguez-andrés Holger Reinecke Yahya sohrabi Department of Internal Medicine and Radboud Center for Infectious Diseases Radboud University Nijmegen Medical Centre6500HBNijmegenthe Netherlands Department of Cardiology I-Coronary and Peripheral Vascular Disease Heart FailureUniversity Hospital MünsterWestfälische Wilhelms-UniversitätMünsterGermany Institutes of Molecular Genetics of the Czech Academy of sciences PragueCzech Republic Department of Medical Genetics Third Faculty of MedicineCharles UniversityPragueCzech Republic

Currently,different types of fasting are becoming increasingly popular for their potential health benefits,particularly in improving cardiometabolic ***,how these practices affect immune function is not well *** a recent study published in Immunity,Janssen et *** into the complex relationship among fasting,refeeding,and the immune *** fasting caused monocyte homing in bone marrow(BM),refeeding escalated monocyte counts in the circulation but altered immune responses to bacterial infection[1].

关键词： becoming fasting she

A novel surface mesh deformation method for handling wing-fuselage intersections

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Chinese Journal of Aeronautics 2017年第1期30卷 264-273页

作者： Mario Jaime Martin-Burgos Daniel González-Juárez Esther andrés-Pérez Fluid Dynamics Branch National Institute for Aerospace Technology (INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Engineering Department lngenieria de Sistemas para la Defensa de Espana (ISDEFE-INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Technical University of Madrid (UPM) Ronda de Valencia 3 28012 Madrid Spain

This paper describes a method for mesh adaptation in the presence of intersections, such as wing-fuselage. Automatic optimization tools, using Computational Fluid Dynamics（CFD） simulations, face the problem to adapt the computational grid upon deformations of the boundary surface. When mesh regeneration is not feasible, due to the high cost to build up the computational grid, mesh deformation techniques are considered a cheap approach to adapt the mesh to changes on the geometry. Mesh adaptation is a well-known subject in the literature; however, there is very little work which deals with moving intersections. Without a proper treatment of the intersections,the use of automatic optimization methods for aircraft design is limited to individual *** proposed method takes advantage of the CAD description, which usually comes in the form of Non-Uniform Rational B-splines（NURBs） patches. This paper describes an algorithm to recalculate the intersection line between two parametric surfaces. Then, the surface mesh is adapted to the moving intersection in parametric coordinates. Finally, the deformation is propagated through the volumetric mesh. The proposed method is tested with the DLR F6 wing-body configuration.

关键词： Aerodynamic shape optimization Computational fluid dynamics Computer-assisted design Geometry parameterizationMesh deformation Non-Uniform Rational B-splines

An Andean tectonic cycle:From crustal thickening to extension in a thin crust(34°-37°sL)

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Geoscience Frontiers 2014年第3期5卷 351-367页

作者： Victor A.Ramos Vanesa D.Litvak andrés Folguera Mauro spagnuolo Laboratorio de Tectonica Andina del Instituto de Estudios Andinos Don Pablo GroeberCONICET-Universidad de Buenos AiresArgentina

several orogenic cycles of mountain building and subsequent collapse associated with periods of shal- lowing and steepening of subduction zones have been recognized in recent years in the Andes. Most of them are characterized by widespread crustal delamination expressed by large calderas and rhyolitic flare-up produced by the injection of hot asthenosphere in the subduction wedge. These processes are related to the increase of the subduction angle during trench roll-back. The Payenia paleoflat-slab, in the southern Central Andes of Argentina and Chile （34° -37°s） recorded a complete cycle from crustal thickening and mountain uplift to extensional collapse and normal faulting, which are related to changes in the subduction geometry. The early stages are associated with magmatic expansion and migration, subsequent deformation and broken foreland. New ages and geochemical data show the middle to late Miocene expansion and migration of arc volcanism towards the foreland region was associated with important deformation in the Andean foothills. However, the main difference of this orogenic cycle with the previously described cycles is that the steepening of the oceanic subducted slab is linked to basaltic flooding of large areas in the retroarc under an extensional setting. Crustal delamination is concentrated only in a narrow central belt along the cordilleran axis. The striking differences between the two types of cycles are interpreted to be related to the crustal thickness when steepening the subducting slab, The crustal thickness of the Altiplano is over 60-80 km, whereas Payenia is less than 42 km in the axial part, and near 30 km in the retroarc foothills. The final extensional regime associated with the slab steepening favors the basaltic flooding of more than 8400 km3 in an area larger than 40,000 km2, through 800 central vents and large fissures. These characteristics are unique in the entire present-day Andes.

关键词： Andes Retroarc magmatism Basaltic floods Crustal delamination Flat-slab

Presence of Fleischer ring and prominent corneal nerves in keratoconus relatives and normal controls

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 922-927页

作者： gnes Kriszt Gergely Losonczy andrs Berta Lili Takcs Department of Ophthalmology University of Debrecen Clinical Center

AIMTo examine the occurrence of commonly known clinical signs of keratoconus (KC), i.e. Fleischer ring, prominent corneal nerves and thinning, among unaffected family members of KC patients and healthy control *** of both eyes of 117 relatives of KC patients having no manifest disease based on videokeratography indices (KC relatives), and 142 controls were used for Pearson correlation and t-test statistics. Correlation of Fleischer ring, prominent corneal nerves and central pachymetry data were tested with each other and with videokeratography indices (KsI, KIsA, 3 and 6 mm Fourier asymmetry, and I-s).REsULTsA moderate correlation was found between Fleischer ring and all examined topographical indices. Most important correlation was present with 6 mm Fourier asymmetry, and corneal pachymetry (r=0.272, Pspectively). similar correlations were found with prominent corneal nerves (r=0.234, Psymmetry and r=-0.235, P=0.0265 for pachymetry). KC family members who exhibited Fleischer ring or prominent nerves had thinner and more asymmetric corneas than those without Fleischer ring or prominent corneal nerves (Ps with t-test and Mann-Whitney rank sum test). Though rarely, Fleischer ring and prominent corneal nerves occurred among normal controls, indicating the existence of forme fruste cases in the normal population. Control subjects, who had corneal Fleischer ring or prominent nerves had corneas more similar to KC than other controls (t-test: increased KsI and KIsA, P=0.048 and 0.012, respectively).CONCLUsIONIn KC family members and healthy individuals, Fleischer ring and prominent corneal nerves are associated with features of KC and may suggest a possibility of forme fruste KC. searching for the possible presence of Fleischer ring or prominent nerves on the cornea may help in the decision whether or not to diagnose subclinical KC in

关键词： forme fruste/subclinical keratoconus Fleischer ring corneal nerves corneal thinning videokeratographic indices iatrogenic keratectasia

Punctual mutations in 23s rRNA gene of clarithromycinresistant Helicobacter pylori in Colombian populations

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World Journal of Gastroenterology 2018年第14期24卷 1531-1539页

作者： andrés Jenuer Matta Diana Carolina Zambrano Alvaro Jairo Pazos Registro Poblacional de Cáncer de Cali Department of Pathology School of Medicine Universidad del Valle Faculty of Education and sports sciences Institución Universitaria Escuela Nacional del Deporte Department of Biology Universidad de Nari?o

AIM To characterize punctual mutations in 23s rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic *** PCR products of 23s rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC) population: TumacoColombia, and 5 from a high-risk population: TuquerresColombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23s rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin ***23s rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, C1770 T, C1954 T1, and G1827 C in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 C, A2144 G and C2196 T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23s rRNA gene in clarithromycin-resistant H. pylori(κ = 0.71).CONCLUsION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23s rRNA gene in clarithromycinresistant H. pylori.

关键词： Clarithromycin In vitro resistance Point mutation Helicobacter pylori Gastric cancer 23s rRNA

Qos in FANET Business and swarm Data

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Computers, Materials & Continua 2022年第7期72卷 1877-1899页

作者： Jesús Hamilton Ortiz Carlos andrés Tavera Romero Bazil Taha Ahmed Osamah Ibrahim Khalaf Close Mobile R&D Telecommunications Ls MadridEspaña COMBA I+D Research Group of Universidad santiago de Cali CaliColombia Autonomous of Madrid University MadridEspaña Al-Nahrain Nanorenewable Energy Research Center in Al-Nahrain University BagdadIraq

This article shows the quality of services in a wireless swarm of drones that form an ad hoc network between them Fly Ad Hoc Networks(FANET).Each drone has the ability to send and receive information(like a router);and can behave as a hierarchical node whit the intregration of three protocols:Multiprotocol Label switch(MPLs),Fast Hierarchical AD Hoc Mobile(FHAM)and Internet Protocol version 6(IPv6),in conclusion MPLs+FHAM+*** metrics analyzed in the FANET are:delay,jitter,throughput,lost and sent packets/*** process was carried out with swarms composed of 10,20,30 and 40 units;In this work,the stage with 40 droneswas analyzed showing registration processes,and sentmessages sequences between different drones that were part of the same swarm.A special analysis about the traffic between drones(end-to-end)was carried out,as well as the possible security flaws in each drone and the current status and future trends in real *** future trends,in a real environment,we took as a starting point,metrics results obtained in the simulation(positive according to the obtained results).These results gave us a clear vision of how the network will behave in a real environment with the aim to carry out the experiment on a physical level in the near *** work also shows the experience quality from the service quality metrics obtained through a mathematical *** quality of experience model will allow us to use it objectively in the agricultural sector,which is a great interest area and is where we are working with *** in this article we show our advances for a business model applied to the aforementioned agricultural sector,as well as the data analysis and services available to the end *** services available to the end customer have been classified into a basic,medium,advanced and plus level.

关键词： Ad hoc home agent(AHA) ad hoc mobile node(AMN) ad hoc correspondent node(ACN) ad hoc mobile anchor point(AMAP) fast hierarchical AD hoc mobile IPv6(FHAMIPv6) label switching router(LsR)label edge router(LER) mobile ad hoc networks(MANET)fly ad hoc network(FANET) quality of services(Qos) quality of experience(QoE)