4,177 research outputs found
STRUCTURAL AND PHOTOPHYSICAL PROPERTIES OF A MONONUCLEAR Re(I) COMPLEX:[P,N-{(C6H5)2(C5H5N)P}Re(CO)3Br]
Indexación: Web of Science; ScieloWe have prepared a new monometallic rhenium(I) carbonyl, the complex [P,N-{(C6H5)2(C5H5N)P}Re(CO)3Br] by direct reaction of (Re(CO)3Br(THF))2 and the ligand (C6H5)2(C5H5N)P The structure in the complex shows the pyridinic-phosphine ligand in a chelating mode, occupying cis positions around the rhenium octahedral environment. The molecule displays an absorption band centered at 315 nm which has been assigned to a MLCT transition, and a luminescence quantum yield of 0.001.http://ref.scielo.org/ptnng
Self-adaptation of Genetic Operators Through Genetic Programming Techniques
Here we propose an evolutionary algorithm that self modifies its operators at
the same time that candidate solutions are evolved. This tackles convergence
and lack of diversity issues, leading to better solutions. Operators are
represented as trees and are evolved using genetic programming (GP) techniques.
The proposed approach is tested with real benchmark functions and an analysis
of operator evolution is provided.Comment: Presented in GECCO 201
THE LINK BETWEEN FARMGATE AND WORLD PRICES IN THE WAKE OF TRADE LIBERALIZATION: THE CASE OF COLOMBIA
The study measures the extent to which farmgate price levels have effectively increased their degree of integration with world price movements following trade liberalization in Columbia. Results show that the extent of integration varies greatly depending upon the crop, and that market-specific policies have isolated some farmers from international influences.Demand and Price Analysis, International Relations/Trade, Marketing,
Balance Sheets and Exchange Rate Policy
We study the relation among exchange rates, balance sheets, and macroeconomic outcomes in a small open economy. Because liabilities are dollarized,' a real devaluation has detrimental effects on entreprenurial net worth, which in turn constrains investment due to financial frictions. But there is an offsetting effect, int hat devaluation expands home output and the return to domestic investment, which are also components of net worth. We show that the impact of an adverse foreign shock can be strongly magnified by the balance sheet effect of the associated real devaluation. But the fall in output employment, and investment is stronger under fixed exchange rates than under flexible rates. Hence the conventional wisdom, that flexible exchange rates are better absorbers of real foreign shocks than are fixed rates, holds in spite of potentially large balance sheet effects.
Oscillation of high energy neutrinos in Choked GRBs
It is believed that choked gamma-ray bursts (CGRBs) are the potential
candidates for the production of high energy neutrinos in GeV-TeV energy range.
These CGRBs out number the successful GRBs by many orders. So it is important
to observe neutrinos from these cosmological objects with the presently
operating neutrino telescope IceCube. We study the three flavor neutrino
oscillation of these high energy neutrinos in the presupernova star environment
which is responsible for the CGRB. For the presupernova star we consider three
different models and calculate the neutrino oscillation probabilities, as well
as neutrino flux on the surface of these star. The matter effect modifies the
neutrino flux of different flavors on the surface of the star. We have also
calculated the flux of these high energy neutrinos on the surface of the Earth.
We found that for neutrino energies below \le 10 TeV the flux ratio does not
amount to 1:1:1, whereas for higher energy neutrinos it does
Fully-automated deep learning pipeline for 3D fetal brain ultrasound
Three-dimensional ultrasound (3D US) imaging has shown significant potential for in-utero assessment of the development of the fetal brain. However, in spite of the potential benefits of this modality over its two-dimensional (2D) counterpart, its widespread adoption remains largely limited by the difficulty associated with its analysis.
While more established 3D neuroimaging modalities, such as Magnetic Res- onance Imaging (MRI), have circumvented similar challenges thanks to reliable, automated neuroimage analysis pipelines, there is currently no comparable pipeline solution for 3D neurosonography.
With the goal of facilitating medical research and encouraging the adoption of 3D US for clinical assessment, the main objective of my doctoral thesis is to design, develop, and validate a set of fundamental automated modules that comprise a fast, robust, fully automated, general-purpose pipeline for the neuroimage analysis of fetal 3D US scans.
For the first module, I propose the fetal Brain Extraction Network (fBEN), a fully-automated, end-to-end 3D Convolutional Neural Network (CNN) with an encoder-decoder architecture. It predicts an accurate binary brain mask for the automated extraction of the fetal brain from standard clinical 3D US scans.
For the second module I propose the fetal Brain Alignment Network (fBAN), a fully-automated, end-to-end regression network with a cascade architecture that accurately predicts the alignment parameters required to rigidly align standard clinical 3D US scans to a canonical reference space.
Finally, for the third module, I propose the fetal Brain Fingerprinting Net- work (fBFN), a fully-automated, end-to-end network based on a Variational AutoEncoder (VAE) architecture, that encodes the entire structural information of the 3D brain into a relatively small set of parameters in a continuously distributed latent space. It is a general-purpose solution aimed at facilitating the assessment of the 3D US scans by recharacterising the fetal brain into a representation that is easier to analyse.
After exhaustive analysis, each module of this pipeline has proven to achieve state-of-the-art performance that is consistent across a wide gestational range, as well as robust to image quality, while requiring minimal pre-processing. Additionally, this pipeline has been designed to be modular, and easy to modify and expand upon, with the purpose of making it as easy as possible for other researchers to develop new tools and adapt it to their needs. This combination of performance, flexibility, and ease of use may have the potential to help 3D US become the preferred imaging modality for researching and assessing fetal development
Contemporary responses to Businesses’ negative Human Rights impact
The article provides a panoramic overview of the factual and legal problems created by transnational business activities that negatively impact human rights around the world, and critically analyzes the strengths and gaps of the various international initiatives created in order to address businesses impact on human rights. The main three international initiatives analyzed are the United Nations Guiding Principles on Business and Human Rights, National Action Plans on Business and Human Rights, and the Draft Treaty on Business and Human Rights. The article intends to organize the vast literature on BHR, serve as a departure point for those interested in researching on this sub-area of international human rights law, and to provide critical analysis of the international legal responses created to address these contemporary human right
Essays on Immigration Policy
Considerable interest has been placed on the subject of what to do with the sizable undocumented population currently residing in the United States. Having a full understanding of the size of this population and the impact immigration policy has on them is of critical importance to policy makers. Data limitations in nationally-representative surveys have limited the analyzes of the effects of immigration policy in the academic literature. As such, this dissertation consists of three essays contributing to the literature on the impact of immigration policy and on identifying unobserved populations.
In my first essay, I examine the labor market response of undocumented youth that participated in the Deferred Action for Childhood Arrivals (DACA) program which provides them temporary deportation relief and work authorization. I use data from the U.S. Citizenship and Immigration Services to construct a probabilistic measure for unobserved DACA participation. Using the American Community Survey (ACS), I estimate a two-sample model of the effect of participating in the DACA program. I also estimate spillover effects of DACA on eligible but non-participating undocumented youth. I find that DACA significantly improved labor market and education outcomes of DACA recipients, with magnitude of the treatment-on-the-treated effects at least twice as large as the intent-to-treat estimates obtained from using only the observed eligibility indicator typically used in literature. Evidence of a negative spillover effect on eligible non-participants is documented with a decrease in labor force participation and school attendance.
My second essay considers nonsampling error due to item nonresponse in the estimates of the size and legal composition of the foreign-born population produced using the ACS. The standard practice to address item nonresponse is to impute values under the assumption that nonresponse is conditionally random. I form credible interval estimates that make no assumptions about the values of missing data by considering all uncertainty due to item nonresponse. Without this assumption, the size of the foreign-born population in the US falls somewhere between 40.4 and 59.4 million as of 2019 compared to the Census estimate of 44.9 million. Bounding estimates of the size of the undocumented population fall between 7.3 and 23.3 million compared to the widely accepted estimate of 11 million undocumented immigrants.
In my third essay, I return to analyzing the effects of the DACA program. I examine misclassification bias arising from item-nonresponse in the estimated intent-to-treat effects of the DACA program. Assigning DACA eligibility is based on the responses to specific demographic questions, any of which the individual may not respond to. If the assumption that nonresponse to these questions are conditionally missing fails, this can lead to traditional misclassification bias and attenuate the results when using imputed values. Adjusting for potential misclassification bias by removing non-respondents leads to estimates of the intent-to-treat effects of DACA on labor market outcomes that are 22% to 77% higher than when including non-respondents, depending on the outcome of interest
Graduate Intership Report AGED 539_ Madera TEC
The graduate internship report included the acquisition of a variety of validation documents, plus information on the development of an 8th-grade agriculture curriculum. In addition, it focuses on recruitment efforts and material as well as developing a PLC culture which is all crucial aspects of opening a new school successfully. All aspects of the curriculum and school culture were designed to be collaborative and hands-on in nature
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