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When Does Natural Science Uncertainty Translate into Economic Uncertainty?
No full textUnderstanding the connection between ecological and economic uncertainty matters when calculating damage estimates used to inform environmental policy. Identifying the role uncertainty plays in market damage estimates is important for policy made using highly variable and stochastic projections on ecological losses. Herein we use the damages caused by invasive species as our motivating example to illustrate our point. We examine how a key economic assumption—the degree of substitutability across marketable goods—influences the importance of narrowing the uncertainty of ecological losses from invasive species. We use a computable general equilibrium model (CGE) capable of evaluating impacts from an invasive species under varying market structures. Focusing in on the emerald ash borer which is destroying ash trees throughout the contiguous United States, our results show why investing in narrowing natural science uncertainty is critical when the economy is constrained or when few economic substitutes exist. The key to understanding the value of natural science information on market damages is to understand how prices adjust given substitution possibilities and how people adapt to the newly invaded world. Mapping this ecological-economic relationship through relative prices has implications for a broader set of environmental issues like climate change and damage compensation given a damaged ecosystem
Social Network Site Relational Reconnection Among Older Adults
No full textThe present study employed a national sample of Americans aged 65+ years to explore social network site (SNS) relational reconnection among older adults. Nearly 60% of the sample had reconnected with a former partner during the previous year; primarily involving dormant friendships and familial relationships, but also encompassing former coworkers and ex-romantic partners. Whether a relationship persisted beyond the initial act of reconnection was related to its level of development prior to losing touch, and the extent to which partners engaged in modality expansion by embracing multiple channels of communication after reconnecting. Older adults with more developed pre-loss-of-contact relationships were also more likely to engage in modality expansion after reconnecting
Controlled Protonation of [2Fe–2S] Leading to MitoNEET Analogues and Concurrent Cluster Modification
No full textMitoNEET, a key regulatory protein in mitochondrial energy metabolism, exhibits a uniquely ligated [2Fe–2S] cluster with one histidine and three cysteines. This unique cluster has been postulated to sense the redox environment and release Fe–S cofactors under acidic pH. Reported herein is a synthetic system that shows how [2Fe–2S] clusters react with protons and rearrange their coordination geometry. The low-temperature stable, site-differentiated clusters [Fe2S2(SPh)3(CF3COO)]2– and [Fe2S2(SPh)3(py)]− have been prepared via controlled protonation below −35 °C and characterized by NMR, UV–vis, and X-ray absorption spectroscopy. Both complexes exhibit anodically shifted redox potentials compared to [Fe2S2(SPh)4]2– and convert to [Fe4S4(SPh)4]2– upon warming to room temperature. The current study provides insight into how mitoNEET releases its [2Fe–2S] in response to highly tuned acidic conditions, the chemistry of which may have further implications in Fe–S biogenesis
Genetic Diversity of New World Crocodilians
No full textGenetic diversity is one of the most important attributes of any population; it is defined as the variation in the amount of genetic information within and among individuals of a population, species, assemblage, or community. It can be expressed as differences between individuals at different levels, such as morphological features, structure and chromosomal number, and polymorphisms of sequences of DNA or proteins. An assessment of genetic diversity is fundamental to population genetic studies and has extremely important applications in conservation biology and the development of management and sustainable use plans. This chapter discusses the main indices that allow analyzing genetic variability and population structure of New World crocodilian populations, the methodologies used to estimate these indices, and the principal population genetic data available for these species. The effective population size concept is also discussed, a fundamental parameter in the study of principally those crocodile populations that have been drastically reduced in size and/or suffered fragmentation of their environments
Double Penalized Semi-Parametric Signed-Rank Regression with Adaptive LASSO
No full textIn this paper, a semi-parametric regression model with an adaptive LASSO penalty imposed on both the linear and the nonlinear components of the mode is considered. The model is rewritten so that a signed-rank technique can be used for estimation. The nonlinear part consists of a covariate that enters the model nonlinearly via an unknown function that is estimated using B-splines. The author shows that the resulting estimator is consistent under heavy-tailed distributions and asymptotic normality results are given. Monte Carlo simulations as well as practical applications are studied to assess the validity of the proposed estimation method
Illusion vs. Disillusion: Chinese Viewers\u27 Articulation of House of Cards
Get PDFThis study explores how Chinese viewers articulate the meaning of the Netflix series “House of Cards” through analyzing viewer comments posted on Sohu Video, which streamed the show in China. A qualitative textual analysis of the comments reveals that the Sohu viewers turned the commenting of the show into articulations of democracy and China’s political conditions. In their articulation, some endorsed American democracy as a superb political system, while others resented it as being dark and corrupt, similar to the one in China. Still other viewers made a connection between “Cards” with China’s lack of freedom of speech. These connections were made under certain social conditions, including China’s internet providing a space for political discourse, tensions among different social forces and conflicting meaning systems existing in today’s China, and Chinese people’s increasing consumption of foreign media content and assumptions. Analyzing a particular case of transnational communication, this study demonstrates how the audience can make meaning of a foreign media product by connecting with their own social context, and how such articulations can be plural and multifaceted
Dinitrogen Insertion and Cleavage by a Metal–Metal Bonded Tricobalt(I) Cluster
No full textReduction of a tricobalt(II) tri(bromide) cluster supported by a tris(β-diketiminate) cyclophane results in halide loss, ligand compression, and metal–metal bond formation to yield a 48-electron CoI3 cluster, Co3LEt/Me (2). Upon reaction of 2 with dinitrogen, all metal–metal bonds are broken, steric conflicts are relaxed, and dinitrogen is incorporated within the internal cavity to yield a formally (μ3-η1:η2:η1-dinitrogen)tricobalt(I) complex, 3. Broken symmetry DFT calculations (PBEο/def2-tzvp/D3) support an N–N bond order of 2.1 in the bound N2 with the calculated N–N stretching frequency (1743 cm–1) comparable to the experimental value (1752 cm–1). Reduction of 3 under Ar in the presence of Me3SiBr results in N2 scission with tris(trimethylsilyl)amine afforded in good yield
Confronting Our Own Complicity: Complexities and Tensions of a Critical Race Feminista Praxis in Higher Education During the Movement for Black Lives
No full textThis chapter discusses critical race feminista praxis, one of the many theoretical and practical approaches that exist among CRT scholars who merge Critical Race Theory (CRT) with other theoretical orientations. Critical race counterstories then function as a way to center the narratives of the multiply marginalized. Juanita pulled her car into the parking lot of a Mediterranean restaurant, the site of the first Women of Color faculty gathering of the academic year. Juanita, a non-Black Chicana feminist and new visiting lecturer at a predominantly white private institution in a conservative town in Texas, was anxious but eager to meet other women of color on campus. In this sense, people as non-Black Chicanx/Latinx must be ready to engage with that reality and formulate new possibilities, ones that people argue people are in the process of fully exploring ourselves
Activation of Prp28 ATPase by Phosphorylated Npl3 at a Critical Step of Spliceosome Remodeling
Get PDFSplicing, a key step in the eukaryotic gene-expression pathway, converts precursor messenger RNA (pre-mRNA) into mRNA by excising introns and ligating exons. This task is accomplished by the spliceosome, a macromolecular machine that must undergo sequential conformational changes to establish its active site. Each of these major changes requires a dedicated DExD/H-box ATPase, but how these enzymes are activated remain obscure. Here we show that Prp28, a yeast DEAD-box ATPase, transiently interacts with the conserved 5\u27 splice-site (5\u27SS) GU dinucleotide and makes splicing-dependent contacts with the U1 snRNP protein U1C, and U4/U6.U5 tri-snRNP proteins, Prp8, Brr2, and Snu114. We further show that Prp28\u27s ATPase activity is potentiated by the phosphorylated Npl3, but not the unphosphorylated Npl3, thus suggesting a strategy for regulating DExD/H-box ATPases. We propose that Npl3 is a functional counterpart of the metazoan-specific Prp28 N-terminal region, which can be phosphorylated and serves as an anchor to human spliceosome