7903 research outputs found
Sort by
Light dark matter constraints from SuperCDMS HVeV detectors operated underground with an anticoincidence event selection
Get PDFThis article presents constraints on dark-matter-electron interactions obtained from the first underground data-taking campaign with multiple SuperCDMS HVeV detectors operated in the same housing. An exposure of 7.63 g−days is used to set upper limits on the dark-matter-electron scattering cross section for dark matter masses between 0.5 and 1000 MeV/2, as well as upper limits on dark photon kinetic mixing and axionlike particle axioelectric coupling for masses between 1.2 and 23.3 eV/2. Compared to an earlier HVeV search, sensitivity was improved as a result of an increased overburden of 225 meters of water equivalent, an anticoincidence event selection, and better pile-up rejection. In the case of dark-matter-electron scattering via a heavy mediator, an improvement by up to a factor of 25 in cross section sensitivity was achieved
Popularising Semiotics
Get PDFSemiotics, deconstructionism, structuralism and postmodernism are words which lurk on boundaries of the consciousness of most of us. But they remain shadowy presences except on the rare occasions when we need to wrestle out of them an explanation of just what they are all about.
In this issue of Trends we grapple with one of them, semiotics. C. S. Peirce, the American pragmatist philosopher who coined the term, saw semiotics as a \u27method of methods\u27, useful in many disciplines to clarify their own theory and practice. Everyone uses signs and symbols. Everyone thinks they know the meanings of the signs and symbols they use. But why do they have meanings? Where do the meanings come from? Why are the signs and symbols used by one person or group so frequently misinterpreted by others?
Semiotics may seem esoteric, but its interests are central to all communication. Consequently, all communicators should be concerned with at least some of the problems dealt with by semioticians.
To guide us on our exploration of semiotics the publishers of Trends, the Centre for the Study of Communication and Culture, have enlisted the aid of Professor Keyan Tomaselli and his colleagues at the Centre for Cultural and Media Studies of the University of Natal, who for some years have been studying the cultural side of semiotics. So eager has their response been that we have devoted two issues of Trends to their reports.
The contents of these two issues manifest the views of the authors more than is usual for Trends, and they are not necessarily those of the editors; but the CSCC feels that the perspective of the CCMS deserves both expression and discussion
Mooring, John, Biology, interviewed by
No full textDr. John Mooring first discovered his passion for studying birds and wind while growing up in Carmel, California. He earned his undergraduate degree in Biology from UC Santa Barbara and later completed his doctorate in Plant Science at UCLA. In 1962, he began his teaching career at Santa Clara University. Beyond the classroom, Dr. Mooring has always found joy in working in the garden or greenhouse, where he experiments with hybridizing selected plant populations and studies chromosomes in both parental plants and their artificial hybrids. Even in retirement, Dr. Mooring remains dedicated to his research, diligently working on his academic publications
Cryogenic optical beam steering for superconducting device calibration
No full textWe have developed a calibration system based on a micro-electro-mechanical system mirror that is capable of delivering an optical beam over a wavelength range of 180 to 2000 nm (0.62 to 6.89 eV) in a sub-Kelvin environment. This portable, integrated system is designed to steer the beam over an ∼3cm×3cm∼3cm×3cm area on the surface of any sensor with a precision of ∼100μm∼100μm, enabling the characterization of device response as a function of position. This fills a critical need in the landscape of calibration tools for sub-Kelvin devices, including those used for dark matter detection and quantum computing. These communities have a shared goal of understanding the impact of ionizing radiation on device performance, which can be pursued with our system. We describe the design of the first-generation calibration system and the results from successfully testing its performance at room temperature and 20 mK
Concentration of Media Ownership
Get PDFMulti-channel cable, direct broadcast satellite and immediate access to computer data banks promise an immense variety ofinformation at our finger tips. But many are questioning whether this will mean real diversity of public access or simply many more channels in the hands of fewer and fewer industrial giants. Tne rapid introduction of new communication technologies is bringing to the fore all of the old policy dilemmas regarding concentration of economic power in the mass media. In the background are the perennial concerns to guarantee the right to communicate and to encourage diversity of opinion in the debate of public decisions.
Some argue that the new multi-channel technologies will automatically solve the problems of spectrum scarcity in broadcasting. What is needed is the profit incentive and free competition to attract large investments for rapid expansion of new services. In this view, the world economic crisis demands that we race to create new information industries to solve unemployment and other problems. Developing countries, too, must open the doors to transnational investment in order to catch up with the technology of the industrial world.
Others contend that this rush to modernise at any cost is destroying the principle of the media as a public trust and is making information a commodity that only those with buying power can have.
This issue reviews some of the rapid changes that are currently taking place in research on economic concentration in the media
From Corporate Complicity to Peace: Restorative Justice for Mining Corporations in Kivu\u27s Coltan Sector
Get PDFThis thesis examines how mining corporations in DR Congo\u27s coltan sector can turn from perpetrators of structural violence to agents of sustainable peace. Research identifies seven forms of corporate complicity in violence: economic exploitation, financial misconduct, political interference, environmental degradation, disingenuous peace initiatives, worker rights violations, and supply chain manipulation.
These practices create “distant markets causing distant harms” and constitute sinful structures systematically harming vulnerable people. Restorative Justice offers a transformative framework for addressing these injustices. Drawing from Desmond Tutu\u27s work, the research establishes a three-dimensional model for corporate conversion: individual moral awakening among leaders, communal engagement fostering collective responsibility, and institutional reform integrating social responsibility into core business strategies. This process reorients corporate agency from profit-maximization toward moral responsibility, service to the common good, and solidarity with communities. The thesis proposes five implementation pathways: industrialization respecting human dignity, fair wages with attention to ex-combatants, track-two diplomacy, community involvement through inclusive business models, and supply chain transparency.
These practices create “distant markets causing distant harms” and constitute sinful structures systematically harming vulnerable people. Restorative Justice offers a transformative framework for addressing these injustices. Drawing from Desmond Tutu\u27s work, the research establishes a three-dimensional model for corporate conversion: individual moral awakening among leaders, communal engagement fostering collective responsibility, and institutional reform integrating social responsibility into core business strategies. This process reorients corporate agency from profit-maximization toward moral responsibility, service to the common good, and solidarity with communities. The thesis proposes five implementation pathways: industrialization respecting human dignity, fair wages with attention to ex-combatants, track-two diplomacy, community involvement through inclusive business models, and supply chain transparency.
This research contributes to theological ethics by bridging Catholic Social Teaching with Business Ethics and Peace Studies, creating an integrated basis for extractive industries in conflict regions. Grounding recommendations in reflection and experience demonstrates how mining corporations can fulfill their moral responsibility to become peace agents in an area devastated by resource-driven conflict
A Novel Exosome-based Suicide Gene Therapy for Brain Cancer Targeting
No full textThe objective of our project is to test the efficacy of delivering an engineered suicide gene to cancer cells and spreading the produced enzyme to neighboring cancer cells via extracellular vesicles, in particular exosomes, for targeted prodrug therapy. Our project focuses specifically on glioblastoma brain cancer, a highly aggressive and malignant form of cancer with very few effective treatment options. Current therapy options are either very dangerous, as is the case with surgery, or affect the entire body, as is the case with chemotherapy. Suicide gene-derived enzyme prodrug therapy is safe targeted method that has the capability to treat brain cancer, but has a few limitations. Our project aims to overcome these limitations by localizing the suicide gene enzyme in the lumen of exosomes, which will facilitate the delivery of the enzyme to uninfected cells. We will first establish stable cell lines to produce therapeutic exosomes, then harvest the exosomes for characterization and functionality testing. We will similarly confirm the presence of our therapeutic enzyme at each step through fluorescent labeling. The successful localization and spread of the engineered enzyme by exosome-mediated delivery will allow for the effect of the suicide gene and prodrug therapy to occur throughout the tumor, increasing its effectiveness in treating the cancer. This novel therapy is targeted at glioblastoma patients, although it is applicable with other forms of cancer. Successful treatment may help improve prognosis and increase the survival rate in glioblastoma patients. Ethical considerations, including cost, safety, and accessibility, will be considered throughout the design process