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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

Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： luis G. Torres Neftalí Rojas Rosario Iturbe Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

Strength and stiffness reduction factors for infilled frames with openings

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 437-454页

作者： luis D.Decanini Laura Liberatore Fabrizio Mollaioli Department of Structural Engineering and Geothecnics "Sapienza" University of Rome

Framed structures are usually infilled with masonry walls. They may cause a significant increase in both stiffness and strength, reducing the deformation demand and increasing the energy dissipation capacity of the system. On the other hand, irregular arrangements of the masonry panels may lead to the concentration of damage in some regions, with negative effects; for example soft story mechanisms and shear failures in short columns. Therefore, the presence ofinfill walls should not be neglected, especially in regions of moderate and high seismicity. To this aim, simple models are available for solid infills walls, such as the diagonal no-tension strut model, while infilled frames with openings have not been adequately investigated. In this study, the effect of openings on the strength and stiffness of infilled frames is investigated by means of about 150 experimental and numerical tests. The main parameters involved are identified and a simple model to take into account the openings in the infills is developed and compared with other models proposed by different researchers. The model, which is based on the use of strength and stiffness reduction factors, takes into account the opening dimensions and presence of reinforcing elements around the opening. An example of an application of the proposed reduction factors is also presented.

关键词： infilled frames openings strength stiffness reduction factor

Culture Mixed-Sex and Monosex of Tilapia in Ponds in Mexico City

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Agricultural Sciences 2015年第2期6卷 187-194页

作者： Jose luis Gomez-Márquez Bertha Pena-Mendoza Maria del Carmen Alejo-Plata Jose luis Guzmán-santiago Laboratorio de Limnología Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoMéxicoD.F.México Campus Puerto Angel Universidad del MarCiudad UniversitariaPuertoángelMéxico

In this study, the growth of Oreochromis niloticus both mixed sex and males sexually reversed were analyzed in concrete ponds in the FES Zaragoza, UNAM, under the environmental conditions of the Mexico City. The experiment was carried from May to November 2013, in two concrete ponds of 50 m2. Similar feeding regime and stocking density of fish were maintained for the culture systems. Different growth parameters like body weight, length, daily weight gain (DWG), specific growth rate (SGR), feed conversion rate (FCR), Fulton’s condition index (K) and survival were analyzed during six months culture period. It was found that culture with monosex males tilapias yielded the highest weight, length, DWG and SGR compared to mixed sex populations tilapias. Water quality was monitored along the experiment. Based on the results, there were statistically significant differences in size (W = 20942.5, p 5 mg/L), warm water (>20°C), productive (3) and slightly basic (pH > 8). Acceptable growth of fish and a yield of 3 ton/ha/6 months were obtained in both two ponds;therefore, the culture of tilapia under conditions of Mexico City was recommended.

关键词： Tilapia Culture Growth Survival Mexico City

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

Cell bioenergetics:Simple logics,complex solut

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BIOCELL 2022年第10期46卷 2217-2220页

作者： luis S.MAYORGA Instituto de Histología y Embriología de Mendoza(IHEM Universidad Nacional de CuyoCONICET)Facultad de Ciencias Exactas y NaturalesMendoza5500Argentina

Cells are open systems that exchange energy and molecules with their *** any material system,they perform all the complex activities required for homeostasis and reproduction,obeying the thermodynamic *** viewpoint will argue that the basic logic governing the energy flux required to preserve cell organization and function is simple:to decrease the activation energy(Ea)of specific *** none of the possible chemical reactions and energy transformations inside a cell occur at a measurable speed at room or body *** or other macromolecular structures speed up particular transformations by decreasing the corresponding energetic ***,to maintain the systems in a homeostatic state,capable of sophisticated functions based on this simple strategy requires an inconceivably complex *** conclusion will point to the challenging and intricate problems that cells have solved to carve the highly regulated channel through which the energy flows,fueling the work of these nanoscale machines.

关键词： Thermodynamics Cellular logics Self-organization Complexity

Traits uncover quasi-neutral community assembly in a coastal heath vegetation

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Journal of Plant Ecology 2019年第4期12卷 703-712页

作者： JoséLuiz Alves Silva Alexandre Fadigas Souza Louis Stephen santiago Programa de Pós-Graduação em Ecologia Departamento de EcologiaUniversidade Federal do Rio Grande do NorteNatal 59078-970Brazil Departamento de Ecologia Universidade Federal do Rio Grande do NorteNatal 59078-970Brazil Department of Botany and Plant Sciences University of California2150 Batchelor HallRiversideCA 92521USA Smithsonian Tropical Research Institute BalboaAncónPanamáRepublic of Panamá

Aims Trait-based approaches are increasingly being used in ecology due to their potential to explain and predict community structure and dynamic regardless of species ***,we asked whether coastal heath vegetation established in stressful habitats could be assembled by quasi-neutral mechanisms based on functional trait *** are organized through quasi-neutral dynamics if abiotic gradients and/or species interactions impose sorting on functional traits and species performances,but not on species phylogenetic relatedness and *** The study was conducted in a coastal area containing tall dunes near the sea,and relatively flat areas punctuated by short palaeodunes further inland,Northeastern South *** evaluated 10 traits of the 21 most abundant species,as well as eight abiotic variables in 70 plots(25 m^(2))established in dune tops,valleys,flat and steep *** effect of environmental filter was tested by linear mixed models(LMM)between each community-weighted mean(CWM)trait and the abiotic variables,and by two indices of environmental filtering based on intra-and interspecific-trait vari-ability relative to null *** evaluate the effect of species inter-actions,we used an index of niche overlap relative to null models,and LMMs between this index and the species richness of *** Findings The environmental filtering index did not deviate from null expect-ations for any *** that included individual variability per-formed similarly to models that used species mean ***,the explicit consideration of environmental gradients by CWM ana-lyses revealed functional patterns that would remain undetected if trait distribution was analyzed *** addition,intraspecific vari-ation in the stem length was an important driver of species diversity as suggested by the relationship between species richness and the niche overlap *** on the occurrence and phylogenetic re-latedness o

关键词： Restinga heath vegetation harsh environment stress-tolerant species response traits

Mainstreaming Disaster Risk Reduction and Climate Change Adaptation in Comprehensive Development Planning of the Cities in Nueva Ecija in the Philippines

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International Journal of Disaster Risk Science 2021年第3期12卷 367-380页

作者： Arneil G.Gabriel Patrick Neil M.santiago Rosemarie R.Casimiro Department of Public Administration Nueva Ecija University of Science and Technology3100 Cabanatuan CityPhilippines

Recent scientific consensus suggests that climate-related disasters are becoming more frequent and ***,increasing importance is given to disaster risk reduction(DRR)and climate change adaptation(CCA)in global *** projected global warming at 1.5℃and the climate variability that the Philippine archipelago experiences make DRR-CCA the key priorities of both the national and local government *** this study,we assessed and measured the degree of mainstreaming of DRR-CCA in the comprehensive development plans(CDPs)of the five component cities in the province of Nueva Ecija in the *** are among the areas in Central Luzon that are susceptible to hydrometeorological and geologic *** distributed survey questionnaires to 25 employees of the local government units in the five component cities in Nueva Ecija who are directly involved in planning *** triangulated their responses using archival data(review of written policies and plans).The main findings of the study indicate that in spite the presence of laws and policies on DRR-CCA,their implementation is only in the preliminary *** results also provide insights to policymakers and future researchers on the challenges and opportunities influencing the systemic mainstreaming of DRR-CCA in the province.

关键词： Climate-related disasters Global warming Local development planning Philippines Southeast Asia

Less is more:dimensionality reduction as a general strategy for more precise luminescence thermometry

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Light(Science & Applications) 2022年第9期11卷 2127-2139页

作者： ERVING XIMENDES RICCARDO MARIN luis DIAS CARLOS DANIEL JAQUE NanoBIG Departamento de Fisica de MaterialesFacultad de CienciasUniversidad Autónoma de MadridC/Francisco Tomás y Valiente 7Madrid 28049Spain NanoBIG Instituto Ramón y Cajal de Investigación Sanitaria(IRYCIS)Ctra.Colmenar km.9.100Madrid 28034Spain Phantom-g CICECO-Aveiro Institute of MaterialsDepartment of PhysicsUniversity of AveiroAveiro 3810-193Portugal

Thermal resolution(also referred to as temperature uncertainty)establishes the minimum discernible temperature change sensed by luminescent thermometers and is a key figure of merit to rank *** has been done to minimize its value via probe optimization and correction of readout artifacts,but little effort was put into a better exploitation of calibration *** this context,this work aims at providing a new perspective on the definition of luminescence-based thermometric parameters using dimensionality reduction techniques that emerged in the last *** application of linear(Principal Component Analysis)and non-linear(t-distributed Stochastic Neighbor Embedding)transformations to the calibration datasets obtained from rare-earth nanoparticles and semiconductor nanocrystals resulted in an improvement in thermal resolution compared to the more classical intensity-based and ratiometric ***,in turn,enabled precise monitoring of temperature changes smaller than 0.1℃.The methods here presented allow choosing superior thermometric parameters compared to the more classical ones,pushing the performance of luminescent thermometers close to the experimentally achievable limits.

关键词： precise dimensionality luminescence