This fresh approach to teaching Quantum Field Theory examines challenging concepts with a minimum of technical detail. The book treats the discussion of the main ideas as more important than the ...presentation of technical mathematical details.
Reactive oxygen species (ROS) are integral components of multiple cellular pathways even though excessive or inappropriately localized ROS damage cells. ROS function as anti-microbial effector ...molecules and as signaling molecules that regulate such processes as NF-kB transcriptional activity, the production of DNA-based neutrophil extracellular traps (NETs), and autophagy. The main sources of cellular ROS are mitochondria and NADPH oxidases (NOXs). In contrast to NOX-generated ROS, ROS produced in the mitochondria (mtROS) were initially considered to be unwanted by-products of oxidative metabolism. Increasing evidence indicates that mtROS have been incorporated into signaling pathways including those regulating immune responses and autophagy. As metabolic hubs, mitochondria facilitate crosstalk between the metabolic state of the cell with these pathways. Mitochondria and ROS are thus a nexus of multiple pathways that determine the response of cells to disruptions in cellular homeostasis such as infection, sterile damage, and metabolic imbalance. In this review, we discuss the roles of mitochondria in the generation of ROS-derived anti-microbial effectors, the interplay of mitochondria and ROS with autophagy and the formation of DNA extracellular traps, and activation of the NLRP3 inflammasome by ROS and mitochondria.
Amid the rise of neoliberalism, globalization, and movements for
civil rights and global justice in the post-World War II era,
Chicanxs in film, music, television, and art weaponized culture to
...combat often oppressive economic and political conditions. They
envisioned utopias that, even if never fully realized, reimagined
the world and linked seemingly disparate people and places. In the
latter half of the twentieth century, Chicanx popular culture
forged a politics of the possible and gave rise to utopian dreams
that sprang from everyday experiences.
In Chicanx Utopias , Luis Alvarez offers a broad study
of these utopian visions from the 1950s to the 2000s. Probing the
film Salt of the Earth , brown-eyed soul music, sitcoms,
poster art, and borderlands reggae music, he examines how Chicanx
pop culture, capable of both liberation and exploitation, fostered
interracial and transnational identities, engaged social movements,
and produced varied utopian visions with divergent possibilities
and limits. Grounded in the theoretical frameworks of Walter
Benjamin, Stuart Hall, and the Zapatista movement, this book
reveals how Chicanxs articulated pop cultural utopias to make sense
of, challenge, and improve the worlds they inhabited.
In many companies, two or three executives jointly hold the responsibilities at the top-from the charismatic CEO who relies on the operational expertise of a COO, to co-CEOs who trust in ...inter-personal bonds to achieve professional results. Their collaboration is essential if they are to address the dilemmas of the top job and the demands of today's corporate governance. Sharing Executive Power examines the behaviour of such duos, trios and small teams, what roles their members play and how their professional and inter-personal relationships bind their work together. It answers some critical questions regarding when and how such power sharing units form and break up, how they perform and why they endure. Understanding their dynamics helps improve the design and composition of corporate power structures. The book is essential reading for academics, graduates, MBAs, and executives interested in enhancing teamwork and cooperation at the top.
The tailored sperm cell Alvarez, Luis
Journal of plant research,
05/2017, Letnik:
130, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Sperm are ubiquitous and yet unique. Genes involved in sexual reproduction are more divergent than most genes expressed in non-reproductive tissues. It has been argued that sperm have been altered ...during evolution more than any somatic cell. Profound variations are found at the level of morphology, motility, search strategy for the egg, and the underlying signalling mechanisms. Sperm evolutionary adaptation may have arisen from sperm competition (sperm from rival males compete within the female’s body to fertilize eggs), cryptic female choice (the female’s ability to choose among different stored sperm), social cues tuning sperm quality or from the site of fertilization (internal vs. external fertilization), to name a few. Unquestionably, sperm represent an invaluable source for the exploration of biological diversity at the level of signalling, motility, and evolution. Despite the richness in sperm variations, only a few model systems for signalling and motility have been studied in detail. Using fast kinetic techniques, electrophysiological recordings, and optogenetics, the molecular players and the sequence of signalling events of sperm from a few marine invertebrates, mammals, and fish are being elucidated. Furthermore, recent technological advances allow studying sperm motility with unprecedented precision; these studies provide new insights into flagellar motility and navigation in three dimensions (3D). The scope of this review is to highlight variations in motile sperm across species, and discuss the great promise that 3D imaging techniques offer into unravelling sperm mysteries.
Redox mediators (RM) are natural or artificial compounds used by microorganisms as electron acceptors and electron donors during electron transfer. Evidence collected in the last years indicates that ...the application of RM in bioelectrochemical systems (BES) enhanced the electron transfer from microorganisms to anodes and from cathodes to microorganisms. This review summarizes the results of using soluble or immobilized RM in BES to produce electricity and for the treatment of contaminants from wastewater effluents. In addition, future research focused on biohydrogen production, recovery or removal metals, and the use of humic substances (HS) extracted from natural environment is proposed.
Technology sector-led urban growth combines digital accumulation and urban accumulation dynamics to transform urban growth processes and outcomes. Together, these forces create the digital growth ...machine: a potent urban growth variation that fosters four related capital accumulation avenues that enable and support its activities. First, the digital growth machine extends long-standing land development and industrial attraction strategies to promote urban growth and increase exchange values. Second, it develops new possibilities for capturing land-related profit beyond traditional land development and intensification strategies. Third, it supports new opportunities for intermediaries to emerge and profit. Fourth, it creates new digital renderings of the city that affect land-related value and perceptions of place. With these processes, the digital growth machine simultaneously furthers dynamics of elite control over land that have become deeply entrenched in cities under capitalism, while qualitatively transforming urban life and the role of cities and land in this economic system.
Reactive oxygen species (ROS) play key roles in mucosal defense, yet how they are induced and the consequences for pathogens are unclear. We report that ROS generated by epithelial NADPH oxidases ...(Nox1/Duox2) during Campylobacter jejuni infection impair bacterial capsule formation and virulence by altering bacterial signal transduction. Upon C. jejuni invasion, ROS released from the intestinal mucosa inhibit the bacterial phosphotyrosine network that is regulated by the outer-membrane tyrosine kinase Cjtk (Cj1170/OMP50). ROS-mediated Cjtk inactivation results in an overall decrease in the phosphorylation of C. jejuni outer-membrane/periplasmic proteins, including UDP-GlcNAc/Glc 4-epimerase (Gne), an enzyme required for N-glycosylation and capsule formation. Cjtk positively regulates Gne by phosphorylating an active site tyrosine, while loss of Cjtk or ROS treatment inhibits Gne activity, causing altered polysaccharide synthesis. Thus, epithelial NADPH oxidases are an early antibacterial defense system in the intestinal mucosa that modifies virulence by disrupting bacterial signaling.
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► Campylobacter jejuni infection triggers epithelial NADPH oxidase activation ► Mucosal H2O2 inhibits phosphotyrosine signaling in extracellular C. jejuni ► The C. jejuni tyrosine kinase Cjtk is required for carbohydrate biosynthesis ► Mucosal ROS and disruption of Cjtk signaling attenuates pathogenicity
We introduce new results connecting differential and morphological operators that provide a formal and theoretically grounded approach for stable and fast contour evolution. Contour evolution ...algorithms have been extensively used for boundary detection and tracking in computer vision. The standard solution based on partial differential equations and level-sets requires the use of numerical methods of integration that are costly computationally and may have stability issues. We present a morphological approach to contour evolution based on a new curvature morphological operator valid for surfaces of any dimension. We approximate the numerical solution of the curve evolution PDE by the successive application of a set of morphological operators defined on a binary level-set and with equivalent infinitesimal behavior. These operators are very fast, do not suffer numerical stability issues, and do not degrade the level set function, so there is no need to reinitialize it. Moreover, their implementation is much easier since they do not require the use of sophisticated numerical algorithms. We validate the approach providing a morphological implementation of the geodesic active contours, the active contours without borders, and turbopixels. In the experiments conducted, the morphological implementations converge to solutions equivalent to those achieved by traditional numerical solutions, but with significant gains in simplicity, speed, and stability.
We offer a review and research agenda for critical remote sensing, defined as inquiries and scientific practices cognizant of the embedding of power within the production, analysis, and ...instrumentalization of satellite imagery. First, we consider critiques of the satellite gaze. Second, we chronicle remote sensing’s evolving political economy, examining the technology’s use by governments, scientists, and commercial and non-governmental actors. Then, we review practices of critical remote sensing, categorized as research (1) exposing injustices; (2) engaging situated knowledges; and (3) empowering marginalized actors. Lastly, we suggest five areas for intertwining critiques and practices and consider possibilities for counter–remote sensing.
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