Selective superoxide generation within mitochondria by the targeted redox cycler MitoParaquat

Superoxide is the proximal reactive oxygen species (ROS) produced by the mitochondrial respiratory chain and plays a major role in pathological oxidative stress and redox signaling. While there are tools to detect or decrease mitochondrial superoxide, none can rapidly and specifically increase superoxide production within the mitochondrial matrix. This lack impedes progress, making it challenging to assess accurately the roles of mitochondrial superoxide in cells and in vivo. To address this unmet need, we synthesized and characterized a mitochondria-targeted redox cycler, MitoParaquat (MitoPQ) that comprises a triphenylphosphonium lipophilic cation conjugated to the redox cycler paraquat. MitoPQ accumulates selectively in the mitochondrial matrix driven by the membrane potential. Within the matrix, MitoPQ produces superoxide by redox cycling at the flavin site of complex I, selectively increasing superoxide production within mitochondria. MitoPQ increased mitochondrial superoxide in isolated mitochondria and cells in culture ~a thousand-fold more effectively than untargeted paraquat. MitoPQ was also more toxic than paraquat in the isolated perfused heart and in Drosophila in vivo. MitoPQ enables the selective generation of superoxide within mitochondria and is a useful tool to investigate the many roles of mitochondrial superoxide in pathology and redox signaling in cells and in vivo

Climate Change: Anticipated Effects on High-Energy Laser Weapon Systems in Maritime Environments

anticipated effects on high energy laser weapon systems in maritime environments. Journal of Applied Meteorology and Climatology, American Meteorological Society, 50, 153-166This study quantifies the potential impacts on ship-defense high-energy-laser (HEL) performance due to atmospheric effects in the marine boundary layer driven by recent observations and analysis of worldwide sea surface temperatures (SSTs). The atmospheric effects are defined using the worldwide probabilistic climatic database available in the High Energy Laser End-to-End Operational Simulation (HELEEOS) model, which includes an SST database for the period 1854–1997. A more recent worldwide sea surface temperature database was provided by the Naval Postgraduate School for the period 1990-2008. Mean differences and trends between the two SST databases are used to deduce possible climate change impacts on simulated maritime HEL engagements. The anticipated effects on HEL propagation performance are assessed at an operating wave-length of 1.0642 um across the world's oceans and mapped to a 1 degree x 1 degree grid. The scenario evaluated is near surface and nearly horizontal over a range of 5000 m in which anticipated clear-air maritime aerosols occur. Summer and winter scenarios are considered. In addition to realistic vertical profiles of molecular and aerosol absorption and scattering, correlated optical turbulence profiles in probabilistic (percentile) format are used

\u3ci\u3eMedicine Meets Virtual Reality 21\u3c/i\u3e

Editors: James D. Westwood, Susan W. Westwood, Li Felländer-Tsai, Cali M. Fidopiastis, Randy S. Haluck, Richard A. Robb, Steven Senger, Kirby G. Vosburgh. Chapter, Varying the Speed of Perceived Self-Motion Affects Postural Control During Locomotion, co-authored by Joshua Pickhinke, Jung Hung Chien, Mukul Mukherjee, UNO faculty and staff members. Virtual reality environments have been used to show the importance of perception of self-motion in controlling posture and gait. In this study, the authors used a virtual reality environment to investigate whether varying optical flow speed had any effect on postural control during locomotion. Healthy young adult participants walked under two conditions, with optical flow matching their preferred walking speed, and with a randomly varying optic flow speed compared to their preferred walking speed. Exposure to the varying optic flow increased the variability in their postural control as measured by area of COP when compared with the matched speed condition. If perception of self-motion becomes less predictable, postural control during locomotion becomes more variable and possibly riskier.https://digitalcommons.unomaha.edu/facultybooks/1261/thumbnail.jp

Business experience and start-up size: buying more lottery tickets next time around?

This paper explores the determinants of start-up size by focusing on a cohort of 6247 businesses that started trading in 2004, using a unique dataset on customer records at Barclays Bank. Quantile regressions show that prior business experience is significantly related with start-up size, as are a number of other variables such as age, education and bank account activity. Quantile treatment effects (QTE) estimates show similar results, with the effect of business experience on (log) start-up size being roughly constant across the quantiles. Prior personal business experience leads to an increase in expected start-up size of about 50%. Instrumental variable QTE estimates are even higher, although there are concerns about the validity of the instrument

UBF levels determine the number of active ribosomal RNA genes in mammals

In mammals, the mechanisms regulating the number of active copies of the ∼200 ribosomal RNA (rRNA) genes transcribed by RNA polymerase I are unclear. We demonstrate that depletion of the transcription factor upstream binding factor (UBF) leads to the stable and reversible methylation-independent silencing of rRNA genes by promoting histone H1–induced assembly of transcriptionally inactive chromatin. Chromatin remodeling is abrogated by the mutation of an extracellular signal-regulated kinase site within the high mobility group box 1 domain of UBF1, which is required for its ability to bend and loop DNA in vitro. Surprisingly, rRNA gene silencing does not reduce net rRNA synthesis as transcription from remaining active genes is increased. We also show that the active rRNA gene pool is not static but decreases during differentiation, correlating with diminished UBF expression. Thus, UBF1 levels regulate active rRNA gene chromatin during growth and differentiation

Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management

Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems

The Vehicle, Fall 1987

Table of Contents Sketches in the SunRodger L. Patiencepage 3 Reflecting PoolRob Montgomerypage 5 Grandpa\u27s Porcelain DollRichard E. Hallpage 6 Tintype 1837Catherine Friemannpage 6 PhotographSteven M. Beamerpage 7 Washerwoman\u27s SongBob Zordanipage 8 Scrambled Eggs for D.O.Lynne A. Rafoolpage 8 my mother would sayMonica Grothpage 9 Retired by His ChildrenDan Von Holtenpage 10 I am the oldestMonica Grothpage 11 Ice on WheatRob Montgomerypage 12 The Nature of the RoseTroy Mayfieldpage 12 Past NebraskaDan Hornbostelpage 13 Five Minute Jamaican VacationChristy Dunphypage 14 PhotographSteven M. Beamerpage 14 The Angry PoemChristy Dunphypage 15 Road UnfamiliarChristy Dunphypage 15 raised voicesMonica Grothpage 16 Old Ladies & MiniskirtsKara Shannonpage 17 FreakspeakBob Zordanipage 18 PortraitDan Von Holtenpage 18 Mobile VacuumKathleen L. Fairfieldpage 19 Rev. Fermus DickSteve Hagemannpage 20 PhotographSteven M. Beamerpage 21 What\u27s the Name of That Flower?Richard Jesse Davispage 22 RequestChristy Dunphypage 23 SketchPaul Seabaughpage 24 ExperiencedMarilyn Wilsonpage 26 Leaving: Two ViewsTina Phillipspage 27 AntaeusDan Von Holtenpage 28 Misogyny at 19J. D. Finfrockpage 29 A Mental CrippleSteve Hagemannpage 32 AssociationsRhonda Ealypage 33 Banana BreadGail Bowerpage 34 Bill and JackBradford B. Autenpage 35 After Image No. 2Rob Montgomerypage 35 VrrooomBeth Goodmanpage 36 Mr. Modern LoverMolly Maddenpage 36 TravelogueRodger L. Patiencepage 37 Down the HighwayJoan Sebastianpage 38 A Retread HeavenRob Montgomerypage 41 StuporDan Von Holtenpage 42 Love Poem After a Seizure in Your BedBob Zordanipage 43 PalsyChristy Dunphypage 44 Interview with Mr. MatthewsBob Zordanipage 45 Chasing Down Hot Air Balloons on a Sunday MorningRob Montgomerypage 48https://thekeep.eiu.edu/vehicle/1049/thumbnail.jp

Oxidized sulfur-rich arc magmas formed porphyry Cu deposits by 1.88 Ga

Most known porphyry Cu deposits formed in the Phanerozoic and are exclusively associated with moderately oxidized, sulfur-rich, hydrous arc-related magmas derived from partial melting of the asthenospheric mantle metasomatized by slab-derived fluids. Yet, whether similar metallogenic processes also operated in the Precambrian remains obscure. Here we address the issue by investigating the origin, fO2, and S contents of calc-alkaline plutonic rocks associated with the Haib porphyry Cu deposit in the Paleoproterozoic Richtersveld Magmatic Arc (southern Namibia), an interpreted mature island-arc setting. We show that the ca. 1886–1881 Ma ore-forming magmas, originated from a mantle-dominated source with minor crustal contributions, were relatively oxidized (1‒2 log units above the fayalite-magnetite-quartz redox buffer) and sulfur-rich. These results indicate that moderately oxidized, sulfur-rich arc magma associated with porphyry Cu mineralization already existed in the late Paleoproterozoic, probably as a result of recycling of sulfate-rich seawater or sediments from the subducted oceanic lithosphere at that time