279 research outputs found
StrainâPromoted Cycloadditions in Lipid Bilayers Triggered by Liposome Fusion
Due to the variety of roles served by the cell membrane, its composition and structure are complex, making it difficult to study. Bioorthogonal reactions, such as the strain promoted azide-alkyne cycloaddition (SPAAC), are powerful tools for exploring the function of biomolecules in their native environment but have been largely unexplored within the context of lipid bilayers. Here, we developed a new approach to study the SPAAC reaction in liposomal membranes using azide- and strained alkyne-functionalized Förster resonance energy transfer (FRET) dye pairs. This study represents the first characterization of the SPAAC reaction between diffusing molecules inside liposomal membranes. Potential applications of this work include in situ bioorthogonal labeling of membrane proteins, improved understanding of membrane dynamics and fluidity, and the generation of new probes for biosensing assays
Risk Factors for Development of Chronic Kidney Disease in Cats
BACKGROUND: Identification of risk factors for development of chronic kidney disease (CKD) in cats may aid in its earlier detection. HYPOTHESIS/OBJECTIVES: Evaluation of clinical and questionnaire data will identify risk factors for development of azotemic CKD in cats. ANIMALS: One hundred and fortyâeight clientâowned geriatric (>9 years) cats. METHODS: Cats were recruited into the study and followed longitudinally for a variable time. Owners were asked to complete a questionnaire regarding their pet at enrollment. Additional data regarding dental disease were obtained when available by development of a dental categorization system. Variables were explored in univariable and multivariable Cox regression models. RESULTS: In the final multivariable Cox regression model, annual/frequent vaccination (P value, .003; hazard ratio, 5.68; 95% confidence interval, 1.83â17.64), moderate dental disease (P value, .008; hazard ratio, 13.83; 95% confidence interval, 2.01â94.99), and severe dental disease (P value, .001; hazard ratio, 35.35; 95% confidence interval, 4.31â289.73) predicted development of azotemic CKD. CONCLUSION: Our study suggests independent associations between both vaccination frequency and severity of dental disease and development of CKD. Further studies to explore the pathophysiological mechanism of renal injury for these risk factors are warranted
Assessing plume impacts caused by polymetallic nodule mining vehicles
Deep-sea mining may be just a few years away and yet society is struggling to assess the positive aspects, such as increasing the supply of metals for battery production to fuel the green revolution, versus the potentially large environmental impacts. Mining of polymetallic (manganese) nodules from the deep ocean is likely to be the first mineral resource targeted and will involve direct impacts to hundreds of km2 of seabed per mine per year. However, the mining activity will also cause the generation of large sediment plumes that will spread away from the mine site and have both immediate and long-term effects over much wider areas. We discuss what the impacts of plumes generated near the seabed by mining vehicles may be and how they might be measured in such challenging environments. Several different mining vehicles are under development around the world and depending on their design some may create larger plumes than others. We discuss how these vehicles could be compared so that better engineering designs could be selected and to encourage innovation in dealing with plume generation and spread. These considerations will aid the International Seabed Authority (ISA) that has the task of regulating mining activities in much of the deep sea in its commitment to promote the Best Available Technology (BAT) and Best Environmental Practice (BEP)
Effects of the level of early productivity on the lifespan of ewes in contrasting flock environments
An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics
For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
Research is needed to inform environmental management of hydrothermally inactive and extinct polymetallic sulfide (PMS) deposits
Polymetallic sulfide (PMS) deposits produced at hydrothermal vents in the deep sea are of potential interest to miners. Hydrothermally active sulfide ecosystems are valued for the extraordinary chemosynthetic communities that they support. Many countries, including Canada, Portugal, and the United States, protect vent ecosystems in their Exclusive Economic Zones. When hydrothermal activity ceases temporarily (dormancy) or permanently (extinction), the habitat and associated ecosystem change dramatically. Until recently, so-called "inactive sulfide" habitats, either dormant or extinct, received little attention from biologists. However, the need for environmental management of deep-sea mining places new imperatives for building scientific understanding of the structure and function of inactive PMS deposits. This paper calls for actions of the scientific community and the emergent seabed mining industry to i) undertake fundamental ecological descriptions and study of ecosystem functions and services associated with hydrothermally inactive PMS deposits, ii) evaluate potential environmental risks to ecosystems of inactive PMS deposits through research, and iii) identify environmental management needs that may enable mining of inactive PMS deposits. Mining of some extinct PMS deposits may have reduced environmental risk compared to other seabed mining activities, but this must be validated through scientific research on a case-by-case basis.FCT: IF/00029/2014/CP1230/CT0002/ UID/05634/2020/ CEECIND005262017/ UID/MAR/00350/2019; Direcao-Geral de Politica do Mar (DGPM) Mining2/2017/005/ Mining2/2017/001info:eu-repo/semantics/publishedVersio
Sonic diaspora, vibrations and rhythm: thinking through the sounding of the Jamaican dancehall session
The propagation of vibrations may provide a better way of understanding diasporic spread than the conventional focus on the circulation of products (Hall 1980, Appadurai 1986, 1996, Gilroy 1993a, Brah 1996). Jamaican sound systems operate as a broadcast medium and a source of CDs, DVDs and other commercial products (Henriques 2007a). But the dancehall sound system session also propagates a broad spectrum of frequencies diffused through a range of media and activities - described as âsoundingâ (following Smallâs 1998 concept of âmusickingâ). These include the material vibrations of the signature low-pitched auditory frequencies of Reggae as a bass culture (Johnson 1980), at the loudness of âsonic dominanceâ (Henriques 2003). Secondly a session propagates the corporeal vibrations of rituals, dance routines and bass-line âriddimsâ (Veal 2007). Thirdly it propagates the ethereal vibrations (Henriques 2007b), âvibesâ or atmosphere of the sexually charged popular subculture by which the crowd (audience) appreciate each dancehall session as part of the Dancehall scene (Cooper 2004). The paper concludes that thinking though vibrating frequencies makes it easier to appreciate how audiences with no direct or inherited connection with a particular music genre can be energetically infected and affected - to form a sonic diaspora
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