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Population structuring of the ubiquitous stingless bee Tetragonisca angustula in southern Brazil as revealed by microsatellite and mitochondrial markers

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Insect Science 2017年第5期24卷 877-890页

作者： Flavio O. Francisco Leandro R. santiago Yuri m. mizusawa Benjamin P. Oldroyd maria C. Arias Departamento de Genetica e Biologia Evolutiva Instituto de Biociencias Universidade de Sao Paulo Rua do MatZo 277 - sala 320Sao Paulo SP Brazi Behaviour and Genetics of Social Insects Lab School of Life and Environmental Sciences A 12 University of Sydney Sydney NSW Australia

Tetragonisca angustula is one of the most widespread stingless bees in the Neotropics. This species swarms frequently and is extremely successful in urban envi- ronments. In addition, it is one of the most popular stingless bee species for beekeeping in Latin America, so nest transportation and trading is common. Nest transportation can change the genetic structure of the host population, reducing inbreeding and increasing homogenization. Here, we evaluate the genetic structure of 17 geographic populations of T. angustula in southern Brazil to quantify the level of genetic differentiation between populations. Analyses were conducted on partially sequenced mitochondrial genes and 11 microsatellite loci of 1002 workers from 457 sites distributed on the mainland and on 3 islands. Our results show that T. angustula populations are highly differentiated as demon- strated by mitochondrial DNA （mtDNA） and microsatellite markers. Of 73 haplotypes, 67 were population-specific. mtDNA diversity was low in 9 populations but microsatellite diversity was moderate to high in all populations. microsatellite data suggest 10 genetic clusters and low level of gene flow throughout the studied area. However, physical barri- ers, such as rivers and mountain ranges, or the presence or absence of forest appear to be unrelated to population clusters. Factors such as low dispersal, different ecological con- ditions, and isolation by distance are most likely shaping the population structure of this species. Thus far, nest transportation has not influenced the general population structure in the studied area. However, due to the genetic structure we found, we recommend that nest transportation should only occur within and between populations that are genetically similar.

关键词： genetic structure islands meliponini microsatellites mtDNA nest transportation

Synthesis, Structural Study and Phase Transitions Characterization by Thermal Analysis and Vibrational Spectroscopy of an Ammonium Rubidium Arsenate Tellurate

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Chemical Research in Chinese Universities 2016年第6期32卷 902-911页

作者： GHORBEL Khouloud LITAIEm Hajer KTARI Lilia GARCIA-GRANDA santiago DAmmAK mohamed Laboratoire de Chimie Inorganique(LCI) Universitd de Sfax Facultd des Sciences de Sfax BP 1171 Sfax 3000 Tunisia Laboratoire de Chimie Physique et Analytique Faeulte de Chimie Universitte d 'Oviedo Oviedo 33006 Espagne

The Rb2.42（NH4）0.58（HAsO4）（H2AsO4）. Te（OH）6 crystals（denoted by RbNAsTe） crystallize in the monoc-linic system, space group P21/n with the following parameters： a=1.3059（5） nm, b=0.6755（3） nm, c=1.6675（6） rim,β=94.126（4）°, Z=4 and V=1.46733（10） nm^3. Thermal analyses（DSC, DTA and TG） confirm the presence of the phasetransition and the temperatttre of the decomposition. The vibrational spectroscopy study at room temperature showthe presence and the independence of anionic groups, cationic groups, and give more importance to the hydrogenbonds. Raman spectra were recorded in the temperature range of 298--503 K. The temperature dependence of theRaman line shift, intensity reduction and the half width detects the phase transitions and confirms their nature. So, thephase transition at 453 K corresponds to the superprotonic-ionic conduction phase transition, and those at 483 and491 K correspond to the decomposition of our material.

关键词： RbNAsTe X-Ray diffraction Differential scanning calorimetry Phase transition Raman spectrometry

Systematic exploration of signal-based indicators for failure diagnosis in the context of cyber-physical systems

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 152-175页

作者： santiago RUIZ-ARENAS Zoltán RUSáK Imre HORVáTH Ricardo mEJí-GUTIERREZ Faculty of Industrial Design Engineering Delft University of Technology Grupo de Investigación en Ingeniería de Diseno Universidad EAFIT

malfunction or breakdown of certain mission critical systems(mCSs) may cause losses of life, damage the environments, and/or lead to high costs. Therefore, recognition of emerging failures and preventive maintenance are essential for reliable operation of mCSs. There is a practical approach for identifying and forecasting failures based on the indicators obtained from real life processes. We aim to develop means for performing active failure diagnosis and forecasting based on monitoring statistical changes of generic signal features in the specific operation modes of the system. In this paper, we present a new approach for identifying emerging failures based on their manifestations in system signals. Our approach benefits from the dynamic management of the system operation modes and from simultaneous processing and characterization of multiple heterogeneous signal sources. It improves the reliability of failure diagnosis and forecasting by investigating system performance in various operation modes, includes reasoning about failures and forming of failures using a failure indicator matrix which is composed of statistical deviation of signal characteristics between normal and failed operations, and implements a failure indicator concept that can be used as a plug and play failure diagnosis and failure forecasting feature of cyber-physical systems. We demonstrate that our method can automate failure diagnosis in the mCSs and lend the mCSs to the development of decision support systems for preventive maintenance.

关键词： Failure indicators Failure classification Failure detection and diagnosis Complex systems

Red-emitting CaWO4:Eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution

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Journal of Rare Earths 2022年第2期40卷 226-233,I0002页

作者： L.X.Lovisa I.m.P.da Silva A.A.G.santiago m.Siu Li E.Longo C.A.Paskocimas m.R.D.Bomio F.V.motta Institute of Physics and Chemistry.Federal University of Itajubd(UNIFEI) ItajubdMG37500-903Brazil LSQm-Laboratory of Chemical Synthesis of materials-Department of materials Engineering Federal University of Rio Grande Do NorteP.O.Box 152459078-900Natal RNBrazil IFSC USPAv.Trabalhador Sao Carlense400CEP 13566-590Sao CarlosSPBrazil CDmF-LIEC UFSCarP.O.Box 67613565-905Sao Carlos.SPBrazil

CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(mAH).The phase formation,morphology,luminescent properties and ene rgy transfer were *** X-ray diffraction(XRD)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary *** growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of *** luminescence spectra of CaWO_(4):Eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 D0→7 F2(Eu^(3+))transition at 624 *** feature signals dominant behavior of the electric dipole *** presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 F3 and 3 H6→3 *** parameters are discussed to characterize CaWO_(4):Eu^(3+),Tm^(3+)*** study of the emission spectrum as a function of the concentration of Eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):Eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIE value of x=0.63 and y=*** photoluminescence results show 97%high color purity for CaWO_(4):4 mol%Eu^(3+),a high CRI(92%)and a low CCT of 1085 *** results demonstrate that the CaWO_(4):Eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices.

关键词： CaWO_(4):Eu^(3+),Tm^(3+)microwave-assisted hydrothermal method Photoluminescence Red phosphor Rare earths

Evaluation of biostimulation and Tween 80 addition for the bioremediation of long-term DDT-contaminated soil

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Journal of Environmental Sciences 2015年第2期27卷 101-109页

作者： Bibiana Betancur-Corredor Nancy J.Pino santiago Cardona Gustavo A.Peuela GDCON Research Group Faculty of Engineering University Research Headquarters (SIU) University of Antioquia School of Geosciences and Environment Faculty of Mines National University of Colombia School of microbiology University of Antioquia

The bioremediation of a long-term contaminated soil through biostimulation and surfactant addition was evaluated. The concentrations of 1,1,1-trichloro-2,2-bis（4-chlorophenyl）ethane（DDT） and its metabolites 1,1-dichloro-2,2-bis（4-chlorophenyl） ethane（DDD） and1,1-dichloro-2,2-bis（4-chlorophenyl） ethylene（DDE） were monitored during an 8-week remediation process. Physicochemical characterization of the treated soil was performed before and after the bioremediation process. The isolation and identification of predominant microorganisms during the remediation process were also carried out. The efficiency of detoxification was evaluated after each bioremediation protocol. Humidity and p H and the heterotrophic microorganism count were monitored weekly. The DDT concentration was reduced by 79% after 8 weeks via biostimulation with surfactant addition（B ＋ S） and 94.3%via biostimulation alone（B）. Likewise, the concentrations of the metabolites DDE and DDD were reduced to levels below the quantification limits. The microorganisms isolated during bioremediation were identified as Bacillus thuringiensis, Flavobacterium sp., Cuprivadius sp.,Variovorax soli, Phenylobacterium sp. and Lysobacter sp., among others. Analysis with scanning electron microscopy（SEm） allowed visualization of the colonization patterns of soil particles. The toxicity of the soil before and after bioremediation was evaluated using Vibrio fischeri as a bioluminescent sensor. A decrease in the toxic potential of the soil was verified by the increase of the concentration/effect relationship EC50 to 26.9% and 27.2% for B ＋ S and B, respectively, compared to 0.4% obtained for the soil before treatment and 2.5%by natural attenuation after 8 weeks of treatment.

关键词： DDT Soil Bioremediation Biostimulation Surfactant Toxicity

Extraction of Nuclear matter Properties from Nuclear masses by a model of Equation of State

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Communications in Theoretical Physics 2001年第11期36卷 583-588页

作者： K.C.Chung C.S.Wang A.J.santiago Instituto de Fisica Universidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil Instituto de FisicaUniversidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil Instituto de FisicaUniversidade do Estado do Rio de JaneiroRio de Janeiro-RJ 20559-900Brazil

The extraction of nuclear matter properties from measured nuclear masses is investigated in the energy density functional formalism of *** is shown that the volume energy a1 and the nuclear incompressibility Ko depend essentially on μnN -+- pZ - 2EN,whereas the symmetry energy J and the density symmetry coefficient L as well as symmetry incompressibility Ks depend essentially on μn - μp,where μp ＝μp - Ec/ Z,μn and μp are the neutron and proton chemical potentials respectively,EN the nuclear energy,and Ec the Coulomb *** obtained symmetry energy is J ＝ 28.5 meV,while other coefficients are uncertain within ranges depending on the model of nuclear equation of state.

关键词： nuclear matter properties,nuclear matter equation of state

Surfactant-free synthesis of metallic bismuth spheres by microwave-assisted solvothermal approach as a function of the power level

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Frontiers of materials Science 2016年第4期10卷 394-404页

作者： miriam ESTRADA FLORES Patricia santiago JACINTO Carmen m. REZA SAN GERmAN Luis RENDON VAZQUEZ Raul BORJA URBY Nicolas CAYETANO CASTRO Instituto de Investigaciones en materiales Circuito Exterior S/N Zona de Institutos Ciudad Universitaria C.P. 04510 Mexico D.F. Mexico Instituto de Fisica Circuito de la Investigaci6n Cientffica Edificio Marcos MoshinskyLaboratorio de Materiales Nanoestructurados Ciudad Universitaria C.P. 04510 Mexico D.F. Mexico Escuela Superior de Ingenierfa Qufmica e Industrias Extractivas Unidad Profesional Adolfo L6pez Mateos Edif. Z-5 2do. Piso Instituto Politecnico Nacional C.P. 07738 Mexico D.F. Mexico Centro de Nanociencias y micro y Nanotecnologfas. Instituto Politecnico Nacional Av. Luis Enrique Erro S/NUnidad Profesional Adolfo Lopez Mateos Zacatenco Delegaci6n Gustavo A. Madero C.P. 07738 Mexico D.F. Mexico

In the present work, the synthesis of micro- and nano-sized spheres of metallic bismuth by microwave-assisted solvothermal method is reported. The synthesis method was carried out at different power levels and at a unique frequency of microwave irradiation. The sphere sizes were controlled by the microwave power level and the concentration of dissolved precursor. Structural and morphological characterization was performed by SEm, HRTEm, EELS and XRD. The results demonstrated that rhombohedral zero valent Bi spheres were synthesized after microwave radiation at 600 and 1200 W. However, if the power level is decreased to 120 W, a monoclinic phase of Bi203 is obtained with a flake-like morphology. In comparison with a conventional hydrothermal process, the microwave-assisted solvothermal approach provides many advantages such as shorter reaction time, optimum manipulation of morphologies and provides a specific chemical phase and avoids the mixture of structural phases and morphologies which is essential for further applications such as drug delivery or functionalization with organic materials, thanks to its biocompatibility.

关键词： microwave oven power level metallic bismuth spherical structures mechanism of formation electron energy loss spectroscopy (EELS)

Impact of the terrestrial reference frame on the determination of the celestial reference frame

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Geodesy and Geodynamics 2019年第1期10卷 58-71页

作者： maria Karbon santiago Belda Tobias Nilsson Institute of Geodesy and Geoinformation University of Bonn Image Processing Laboratory (IPL)-Laboratory of Earth Observation (LEO) University of Valencia Lantmateriet

Currently three up-to-date Terrestrial Reference Frames(TRF) are available, the ITRF2014 from IGN, the DTRF2014 from DGFI-TUm, and JTRF2014 from JPL. All use the identical input data of space-geodetic station positions and Earth orientation parameters, but the concept of combining these data is fundamentally different. The IGN approach is based on the combination of technique solutions, while the DGFI is combining the normal equation systems. Both yield in reference epoch coordinates and velocities for a global set of stations. JPL uses a Kalman filter approach, realizing a TRF through weekly time series of geocentric coordinates. As the determination of the CRF is not independent of the TRF and vice versa, the choice of the TRF might impact on the CRF, Within this work we assess this *** find that the estimated Earth orientation parameter(EOP) from DTRF2014 agree best with those from ITRF2014, the EOP resulting from JTRF2014 show besides clear yearly signals also some artifacts linked to certain stations. The estimated source position time series however, agree with each other better than ±1 μas. When fixing EOP and station positions we can see the maximal effect of the TRF on the CRF. Here large systematics in position as well as proper motion arise. In case of ITRF2008 they can be linked to the missing data after 2008. By allowing the EOP and stations to participate in the adjustment,the agreement increases, however, systematics remain.

关键词： Reference frames CRF TRF DTRF2014 JTRF2014 ITRF2014

The change of paradigm in the treatment of HER2-positive breast cancer with the development of newgeneration antibody-drug conjugates

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Cancer Drug Resistance 2023年第1期6卷 45-58页

作者： santiago Escriva-de-Romani Cristina Saura medical Oncology Service Breast Cancer UnitVall d’Hebron Institute of Oncology(VHIO)Passeig de la Vall d’Hebron119Barcelona 08035Spain

HER2-positive breast cancer is an aggressive *** a result of the development of specific HER2-targeted therapies,such as trastuzumab,more than 20 years ago,the prognosis of these patients has *** HER2-positive breast cancer patients are achieving better survival rates upon treatment with anti-HER2 therapies than patients with HER2-negative *** HER2 blockade with trastuzumab and pertuzumab combined with a taxane achieved an unprecedented survival of over 57 months in first-line *** emtansine,the first antibody-drug conjugate approved for patients in second-line treatment was a potent cytotoxic agent bound to trastuzumab and is currently a standard therapeutic *** the progress in treatment development,most patients develop resistance and eventually *** in the design of antibody-drug conjugates have led to the development of new generation drugs with enhanced properties,such as trastuzumab deruxtecan and trastuzumab duocarmazine,which are significantly changing the paradigm in the treatment of HER2-positive metastatic breast cancer.

关键词： Breast cancer HER2-positive ADCs New drugs mechanisms of resistance