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Trace and rare earth element geochemistry of the black and grey shales of the Calabar Flank, Southeastern Nigeria: constraints on the depositional environment and the degree of metal enrichment

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Acta Geochimica 2021年第3期40卷 312-324页

作者： Christopher Iorfa Adamu Benjamin Odey Omang Oluwaseye Peter Oyetade Otu Johnson therese ntonzi nganje Department of Geology Faculty of Physical ScienceUniversity of CalabarCross River StateNigeria Department of Geology Faculty of ScienceUniversity of BeninEdo StateNigeria

This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar *** main aim is to infer their depositional environment and the degree of their metal *** shale samples were analyzed using inductively coupled plasma mass *** results indicated that the mean concentrations of K,Na,and Fe in Nkporo and Ekenkpon Shales are 1.45,0.4,and 4.17 wt%,and 1.11,0.44,and 5.42 wt%;*** Nkporo Shale is enriched with the following trace elements;P>Mn>Sr>Ba>Zn>Ce>Rb>Zr>V>Cr>Ni and depleted in the following trace elements;Ta>Ge>Sb>Bi>Cd>Ag>Te>In>*** the Ekenkpon Shale is enriched with the following trace elements;P>Mn>Ba>Sr>V>Ce>Zr>Rb>Cr>Zn>Ni and depleted in;Sb>Ge>Bi>Ag>Ce>Te>In>*** concentration of redox-sensitive elements such as V,Ni,Mo,U,Cu,Cr,Re,Cd,Sb,Ti,Mn,and their ratio V/Mo and U/Mo in the black and grey shale samples show different *** REE obtained from the Nkporo and Ekenkpon Shales were PAAS *** Nkporo Shale showed a slightly flat light rare-earth element(LREE),middle rare-earth element(MREE),and heavy rare earth element(HREE)pattern ***/Ce*ranges from 0.95 to 1.09 in Nkporo Shale and 0.67 to 1.40 in Ekenkpon *** Ekenkpon Shale showed a slight LREE,MREE enrichment,and depleted HREE *** Mn contents and U/Mo ratio in Nkporo and Ekenkpon Shales suggests a poor oxygen transitional *** V/Mo and V/(V+Ni)ratios indicated that the Nkporo shales were deposited in an anoxic to suboxic conditions and Ekenkpon shales were also deposited under an anoxic to suboxic *** V/Ni ratio indicated that the organic matter in the Nkporo shale is terrigenous while that of the Ekenkpon shales are both terrigenous and marine in origin.

关键词： Rare-earth elements(REE) Trace elements Calabar Flank Suboxic Anoxic

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Heavy Metal Contamination of Surface Soil in Relationship to Land Use Patterns: A Case Study of Benue State, Nigeria

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Materials Sciences and Applications 2010年第3期1卷 127-134页

作者： Christopher Iorfa Adamu therese ntonzi nganje 不详

A detailed investigation was conducted on the relationship between land use patterns and trace metal content in surface soils of the Benue State to assess soil environmental quality. Results revealed that metals levels were generally high in mineralized and urban soils and lower in agricultural soils whilst forest soils were lease by anthropogenic pollution. Mineralized soils developed from weathered sulphides were rich in lead (Pb), zinc (Zn), and cadmium (Cd). Urban soils accumulated copper (Cu), Zn, and Cd most probably from refuse dumps, gasoline combustion and farming. Agricultural soils were enriched in arsenic (As) and to a lesser degree Pb and Cd originating most probably from the application of pesticides, manure and fertilizers. A pollution index (PI) based on plant-tolerant contamination levels, indicates that multi-element contamination in soils is low and implies that the sampled soils could be cultivated for crop production especially away from point sources of pollution. The degree of anthropogenic pollution was high for As (80%), and Pb (54%), moderate for Zn (47%), Cd (40%), and low for Cu (27%). Correlations (r) are significant between Zn- Pb (0.7), Cu-As (0.6) in mineralized soils, between Zn-Cu (0.64), Zn-Cd (0.5), Cu-Cd (0.6), in urban soils, As-Cd (0.61), in agricultural soils and Zn-Pb (0.82) in forest soils. These distinct relationships indicate a common source or similar geochemical control. Based on the overall evaluation, recommendation in respect of contamination, control and monitoring strategies as well as land use planning in the study area are presented.

关键词： Heavy Metals Pollution Index Surface Soil Land Use

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Heavy Metal Contamination of Surface Soil in Relationship to Land Use Patterns: A Case Study of Benue State, Nigeria

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Materials Sciences and Applications 2010年第3期

作者： Christopher Iorfa Adamu therese ntonzi nganje

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From Solar System to Exoplanets:What can we learn from Planetary Spectroscopy?

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Research in Astronomy and Astrophysics 2022年第12期22卷 1-14页

作者： therese Encrenaz LESIA Paris Observatory-PSL UniversitéCNRSSorbonne UniversitéUniversitéde ParisParisFrance

The purpose of this paper is to address the question:Using our knowledge of infrared planetary spectroscopy,what can we learn about the atmospheres of exoplanets?In a first part,a simplified classification of exoplanets,assuming thermochemical equilibrium,is presented,based on their masses and their equilibrium temperatures,in order to propose some possible estimations about their atmospheric *** the second part,infrared spectra of planets are discussed,in order to see what lessons can be drawn for exoplanetary *** the last part,we consider the solar system as it would appear from a star located in the ecliptic *** first appears that the solar system(except in a few specific cases)would not be seen as a multiple system,because,contrary to many exoplanetary systems,the planets are too far from the Sun and the inclinations of their orbits with respect to the ecliptic plane are too *** transit synthetic spectra of solar system planets are used to discuss the relative merits of transmission and direct emission spectroscopy for probing exoplanetary atmospheres.

关键词： planets and satellites:atmospheres planets and satellites:composition (stars:)planetary systems

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Numerical Groundwater Flow Modeling of the Coastal Plain Sand Aquifer, Akwa Ibom State, SE Nigeria

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Journal of Water Resource and Protection 2014年第4期6卷 193-201页

作者： Aniekan Edet Ramadan Abdelaziz Broder Merkel Chiedu Okereke therese nganje 1Department of Geology University of Calabar Calabar Nigeria 2Departement for Geology TU Bergakademie Freiberg Freiberg Germany Departement for Geology TU Bergakademie Freiberg Freiberg Germany Department of Geology University of Calabar Calabar Nigeria

Akwa Ibom State is located in the Niger delta region of Nigeria. The coastal plain sand aquifer, which underlies the area, is the major source of potable water for domestic, agricultural, and industrial use. The increase in demand for water has led to an increased exploitation of the aquifer in the last few years. Hence it is essential to quantify the amount of exploitable water in the aquifer. To achieve this goal, a regional numerical groundwater flow model using MODFLOW was calibrated under steady-state conditions to determine the aquifer’s hydraulic conductivity (K) and the recharge characteristics of the area. The hydraulic conductivity and recharge values from the pilot points calibration ranged from 1 to 75 m/d and 5.89 × 10-6 m3/d to1.23 × 10-4 m3/d. The calculations of the model showed that the average recharge rate amounts 0.40l/s/km2 or 12.60 mm/year. The estimated recharge suggests a high groundwater potential for the area. This is the first time that such a study has been carried out in the area, and it will serve as an important basis for future groundwater management and simulation of transient groundwater flow modeling in Akwa Ibom State.

关键词： Akwa Ibom Coastal Aquifer Modeling MODFLOW

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Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

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Frontiers in Energy 2019年第3期13卷 522-538页

作者： Pedro PONCE therese PEFFER Arturo MOLINA Tecnologico de Monterrey calle del puente 222 MexicoMexico CityNon-US/Non-Canadian 64849Mexico California Institute for Energy and Environment University of California BerkeleyBerkeleyCA 94720USA

It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (SDT) fuzzy signal detection theory (FSDT) chi-square (CS) test

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Modeling analytics in COVID-19: prediction, prevention, control, and evaluation

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Journal of Management Analytics 2021年第3期8卷 424-442页

作者： Yang Lu therese L.Williams Department of Information Systems and Operations Management University of Central OklahomaEdmondOKUSA

The outbreak of COVID-19 has attracted attention from all around the *** and institutions have adopted ways to fight COVID-19, but itsprevalence is still strong. The SIR model has important reference value for thenovel coronavirus epidemic, offering both preventive measures and the ability topredict future trends. Based on an analysis of the classical epidemiological SIRmodel along with key parameters, this paper aims to analyze the patterns ofCOVID-19, to discuss potential anti-COVID-19 measures, and to explain whywe need to conduct appropriate measures against COVID-19. The use of theSIR model can play an important role in public health emergencies. Among theparameters of the SIR model, the contact ratio and the reproduction ratio arethe factors that have the potential to mitigate the consequences of ***-COVID-19 measures include wearing a mask, washing one’s hands,keeping social distance, and staying at home if possible.

关键词： COVID-19 epidemiological compartment model SIR model the contact ratio the reproduction ratio social distancing

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Review on Dynamic Bandwidth Allocation of GPON and EPON

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Journal of Electronic Science and Technology 2020年第4期18卷 297-307页

作者： Theresal Thangappan Brintha therese Adi Suvarnamma Gadda Sai Swapna School of Electronics and Communication Engineering Vellore Institute of Technology(Chennai Campus)Chennai 632014 School of Electronics and Communication Engineering Vels UniversityChennai 600117 School of Electronics and Communication Engineering Government Polytechnic CollegeAdhoni 518301

The passive optical network(PON)technology has been drastically improved in recent *** spite of using the optical technology,the utilization of the entire bandwidth is a very challenging *** main categories of PON are the Ethernet passive optical network(EPON)and gigabit passive optical network(GPON).These two networks use the dynamic bandwidth allocation(DBA)algorithm to attain the maximum usage of bandwidth,which is provided in the network dynamically according to the need of the customers with the support of the service level agreement(SLA).This paper will provide a clear review about the DBA algorithm of both technologies as well as the comparison。

关键词： Dynamic bandwidth allocation(DBA) Ethernet passive optical network(EPON) gigabit passive optical network(GPON)

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Blast disruption using 3D grids/perforated plates for vehicle protection

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Defence Technology（防务技术） 2023年第7期25卷 60-68页

作者： therese Schunck Dominique Eckenfels Laurent Sinniger French-German Research Institute of Saint-Louis ISL5 Rue Du General Cassagnou68300Saint-LouisFrance

In this work, blast disruption and mitigation using 3D grids/perforated plates were tested for underbelly and side protection of vehicles. Two vehicle simulants were used: a small-scale one for side vehicle protection assessment and a true-to-scale simulant for underbelly protection testing. The deformation of target plates was assessed. These were either unprotected or protected by three different types of disruptors. The first disruptor was made of a sandwich structure of two perforated plates filled with a thin aluminum structure allowing the air to pass through. The two other disruptors were made of pieces of cast metallic foam. Two different kinds of foams were used: one with large cells and the second one with small cells. Beforehand, the mitigation efficiency of the disruptors was evaluated using an explosivedriven shock tube(EDST). The experiments showed that blast disruption/mitigation by 3D grid/perforated plate structures was not suitable for vehicle side protection. However, 3D grids/perforated structures proved to be relatively effective for underbelly protection compared to an equivalent mass of steel.

关键词： Blast Mitigation Perforated plates 3D grids Vehicle protection

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Development of PROTACS degrading KRAS and SOS1

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Oncology Research 2024年第8期32卷 1257-1264页

作者： GERHARD HAMILTON MARIE-therese EGGERSTORFER SANDRA STICKLER Institute of Pharmacology Medical University of ViennaVienna1090Austria

The Kirsten rat sarcoma virus—son of sevenless 1(KRAS-SOS1)axis drives tumor growth preferentially in pancreatic,colon,and lung ***,KRAS G12C mutated tumors can be successfully treated with inhibitors that covalently block the cysteine of the switch II binding pocket of ***,the range of other KRAS mutations is not amenable to treatment and the G12C-directed agents Sotorasib and Adragrasib show a response rate of only approximately 40%,lasting for a mean period of 8 *** approach to increase the efficacy of inhibitors is their inclusion into proteolysis-targeting chimeras(PROTACs),which degrade the proteins of interest and exhibit much higher antitumor activity through multiple cycles of ***,PROTACs have been developed based on KRAS-or SOS1-directed inhibitors coupled to either von Hippel-Lindau(VHL)or Cereblon(CRBN)ligands that invoke the proteasomal *** of these PROTACs show increased activity in vitro and in vivo compared to their cognate inhibitors but their toxicity in normal tissues is not *** CRBN PROTACs containing thalidomide derivatives cannot be tested in experimental *** to such PROTACS arises through downregulation or inactivation of CRBN or factors of the functional VHL E3 ubiquitin *** highly active KRAS and SOS1 PROTACs have been formulated their clinical application remains difficult.

关键词： Proteolysis-targeting chimeras(PROTACs) Kirsten rat sarcoma virus(KRAS) Son of sevenless 1(SOS1) Von Hippel-Lindau Cereblon

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