447 research outputs found
Best way to prevent firearm violence: Limit access to firearms
The increased publicity of mass shootings and the COVID-19 pandemic have fueled American demand for firearm purchases. Firearm violence has largely been blamed on people with mental illnesses instead of firearm accessibility, despite the lack of population-level evidence associating mental illness with firearm violence perpetration. We support interventions and policies to limit firearm access in homes, schools, and by all intimate partners who have been convicted of domestic abuse. We advocate for restrictions on the civilian purchases of semi-automatic rifles and large capacity magazines. Finally, we call for research addressing firearm violence as an environmental and structural issue, not an intrapersonal one
Continuous and Segmented Flow Microfluidics: Applications in High-throughput Chemistry and Biology
This account highlights some of our recent activities focused on developing microfluidic technologies for application in high-throughput and high-information content chemical and biological analysis. Specifically, we discuss the use of continuous and segmented flow microfluidics for
artificial membrane formation, the analysis of single cells and organisms, nanomaterial synthesis and DNA amplification via the polymerase chain reaction. In addition, we report on recent developments in small-volume detection technology that allow access to the vast amounts of chemical and
biological information afforded by microfluidic systems
Density Matrix Approach to Local Hilbert Space Reduction
We present a density matrix approach for treating systems with a large or
infinite number of degrees of freedom per site with exact diagonalization or
the density matrix renormalization group. The method is demonstrated on the 1D
Holstein model of electrons coupled to Einstein phonons. In this system, two or
three optimized phonon modes per site give results as accurate as with 10-100
bare phonon levels per site.Comment: 4 pages, 4 figure
Directed Evolution of Microorganisms for Engineered Living Materials
Microorganisms can create engineered materials with exquisite structures and
living functionalities. Although synthetic biology tools to genetically
manipulate microorganisms continue to expand, the bottom-up rational design of
engineered living materials still relies on prior knowledge of
genotype-phenotype links for the function of interest. Here, we utilize a
high-throughput directed evolution platform to enhance the fitness of whole
microorganisms under selection pressure and identify novel genetic pathways to
program the functionalities of engineered living materials. Using
Komagataeibacter sucrofermentans as a model cellulose-producing microorganism,
we show that our droplet-based microfluidic platform enables the directed
evolution of these bacteria towards a small number of cellulose overproducers
from an initial pool of 40'000 random mutants. Sequencing of the evolved
strains reveals an unexpected link between the cellulose-forming ability of the
bacteria and a gene encoding a protease complex responsible for protein
turnover in the cell. The ability to enhance the fitness of microorganisms
towards specific phenotypes and to discover new genotype-phenotype links makes
this high-throughput directed evolution platform a promising tool for the
development of the next generation of engineered living materials
The role of optimization in the human dynamics of tasks execution
In order to explain the empirical evidence that the dynamics of human
activity may not be well modeled by Poisson processes, a model based on queuing
processes were built in the literature \cite{bar05}. The main assumption behind
that model is that people execute their tasks based on a protocol that execute
firstly the high priority item. In this context, the purpose of this letter is
to analyze the validity of that hypothesis assuming that people are rational
agents that make their decisions in order minimize the cost of keeping
non-executed tasks on the list. Therefore, we build and solve analytically a
dynamic programming model with two priority types of tasks and show that the
validity of this hypothesis depends strongly on the structure of the
instantaneous costs that a person has to face if a given task is kept on the
list for more than one step. Moreover, one interesting finding is that in one
of the situations the protocol used to execute the tasks generates complex one
dimensional dynamics
Opto-mechanical measurement of micro-trap via nonlinear cavity enhanced Raman scattering spectrum
High-gain resonant nonlinear Raman scattering on trapped cold atoms within a
high-fineness ring optical cavity is simply explained under a nonlinear
opto-mechanical mechanism, and a proposal using it to detect frequency of
micro-trap on atom chip is presented. The enhancement of scattering spectrum is
due to a coherent Raman conversion between two different cavity modes mediated
by collective vibrations of atoms through nonlinear opto-mechanical couplings.
The physical conditions of this technique are roughly estimated on Rubidium
atoms, and a simple quantum analysis as well as a multi-body semiclassical
simulation on this nonlinear Raman process is conducted.Comment: 7 pages, 2 figure
A Spectroscopic Search for Leaking Lyman Continuum at Zeta Approximately 0.7
We present the results of rest-frame, UV slitless spectroscopic observations of a sample of 32 z approx. 0.7 Lyman Break Galaxy (LBG) analogs in the COSMOS field. The spectroscopic search was performed with the Solar Blind Channel (SBC) on HST. While we find no direct detections of the Lyman Continuum we achieve individual limits (3sigma) of the observed non-ionizing UV to Lyman continuum flux density ratios, f(sub nu)(1500A)/f(sub nu)(830A) of 20 to 204 (median of 73.5) and 378.7 for the stack. Assuming an intrinsic Lyman Break of 3.4 and an optical depth of Lyman continuum photons along the line of sight to the galaxy of 85% we report an upper limit for the relative escape fraction in individual galaxies of 0.02 - 0.19 and a stacked 3sigma upper limit of 0.01. We find no indication of a relative escape fraction near unity as seen in some LBGs at z approx. 3. Our UV spectra achieve the deepest limits to date at any redshift on the escape fraction in individual sources. The contrast between these z approx. 0.7 low escape fraction LBG analogs with z approx. 3 LBGs suggests that either the processes conducive to high f(sub esc) are not being selected for in the z less than or approx.1 samples or the average escape fraction is decreasing from z approx. 3 to z approx. 1. We discuss possible mechanisms which could affect the escape of Lyman continuum photon
A theory-based framework for understanding the establishment, persistence, and diffusion of community-based conservation
Over decades, biodiversity conservation researchers and practitioners have developed theories and conceptual frameworks to inform the planning, implementation, and evaluation of community-based conservation (CBC). While a diversity of mechanisms for understanding and supporting CBC has helped tailor approaches to local needs and conditions, the absence of a unified lens to understand CBC has limited the capacity for integrating foundational theory into practice more systemically, and for learning across different projects, stakeholders, and institutions. We introduce a theory-based framework called “the CBC framework” that draws upon three foundational theories from sociology, economics, and political science to understand the establishment, persistence, and diffusion of CBC. Experience applying aspects of the framework within different conservation organizations demonstrates how this integrative approach can provide a gateway for practitioners to engage with social science theory to understand the status and context of CBC interventions and efforts. For practitioners, scientists, evaluators, and strategists, the framework can guide the design of CBC interventions and monitoring and evaluation systems to facilitate theory-based learning and enable evidence-informed decision-making. Approaches like the CBC framework that facilitate collaborative planning, evaluation, and research can help better integrate social science theory in conservation practice while increasing the capacity for conservation scientists, practitioners, and stakeholders to learn together and adaptively manage CBC to deliver positive results for both people and nature
Legitimizing leisure experiences as emotional work: A post-humanist approach to gendered equine encounters
** From Crossref via Jisc Publications Router.
** Licence for VoR version of this article starting on 08-06-2018: http://onlinelibrary.wiley.com/termsAndConditions#vorThis is the peer reviewed version of the following article: Finkel, R. & Danby, P. (2018) Legitimizing leisure experiences as emotional work: A post-humanist approach to gendered equine encounters. Gender, Work & Organization, 26(3), pp. 377-391, which has been published in final form at https://doi.org/10.1111/gwao.12268. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Due to changes in lifestyle and work patterns, education and values associated with wellbeing, non‐human animals are now incorporated into a range of human experiences and environments. This research specifically focuses on human–equine relations, examining blurred boundaries between therapeutic and recreational interspecies encounters. It is acknowledged that human–equine relations are often gendered and this research focuses mainly on women's narratives. Viewed through the post‐humanist lens, horses now form kinship and companionship roles, particularly for women, where relations have become mutually emotionally dependent as a result of interspecies communication and embodied encounters. Research utilizes feminist post‐humanist and cultural politics of emotion frameworks associate with the co‐agency on the co‐agency of animals. Embedded in the concept of equiscapes, or post‐humanist leisure spaces, research methods employ qualitative approaches, including in‐depth interviews, participant diaries and multispecies ethnography. Findings reveal how women make considerable investments in equine activities, which develops mutual welfare and wellbeing. Yet, despite these benefits, emotional and other expenditures are justified in work discourses to legitimize them as valuable to themselves, their families and their communities.div_BaM26pub5397pub
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