Temperature, Hatch Date, and Prey Availability Influence Age-0 Yellow Perch Growth and Survival

Throughout their range, Yellow Perch Perca flavescens are an important ecological and economic component of many fisheries, but they often exhibit highly variable recruitment. Much research effort has been devoted to better understanding the mechanisms responsible for these erratic recruitment patterns, yet few studies have examined this process at the detail necessary to reveal complex interactions that may exist across multiple early life stages. Our current understanding of the early life recruitment patterns of Yellow Perch suggests a strong abiotic component. Using existing information, we developed three working hypotheses to examine Yellow Perch recruitment at two larval stages (5–14 and 15–24 d old) and to further identify the overarching mechanisms (abiotic versus biotic) related to Yellow Perch recruitment in 332-ha Pelican Lake, Nebraska, during 2004–2012. Larval Yellow Perch growth and mortality were largely regulated by hatching date, temperature, and zooplankton availability. The growth of young larval Yellow Perch (5–14 d old) was positively related to temperature and hatch date; that of old larval perch (15–24 d old) was positively related to water temperature and postlarval age-0 (≤25 mm TL) Yellow Perch density but negatively related to the available preferred zooplankton biomass. Mortality was inversely related to total zooplankton biomass and water temperature. Our results describe a model with two potential Yellow Perch recruitment bottlenecks, one immediately posthatch that is regulated by hatch date and temperature and another during the older larval stage that is regulated by temperature and zooplankton

Temperature, Hatch Date, and Prey Availability Influence Age-0 Yellow Perch Growth and Survival

Throughout their range, Yellow Perch Perca flavescens are an important ecological and economic component of many fisheries, but they often exhibit highly variable recruitment. Much research effort has been devoted to better understanding the mechanisms responsible for these erratic recruitment patterns, yet few studies have examined this process at the detail necessary to reveal complex interactions that may exist across multiple early life stages. Our current understanding of the early life recruitment patterns of Yellow Perch suggests a strong abiotic component. Using existing information, we developed three working hypotheses to examine Yellow Perch recruitment at two larval stages (5–14 and 15–24 d old) and to further identify the overarching mechanisms (abiotic versus biotic) related to Yellow Perch recruitment in 332-ha Pelican Lake, Nebraska, during 2004–2012. Larval Yellow Perch growth and mortality were largely regulated by hatching date, temperature, and zooplankton availability. The growth of young larval Yellow Perch (5–14 d old) was positively related to temperature and hatch date; that of old larval perch (15–24 d old) was positively related to water temperature and postlarval age-0 (≤25 mm TL) Yellow Perch density but negatively related to the available preferred zooplankton biomass. Mortality was inversely related to total zooplankton biomass and water temperature. Our results describe a model with two potential Yellow Perch recruitment bottlenecks, one immediately posthatch that is regulated by hatch date and temperature and another during the older larval stage that is regulated by temperature and zooplankton

Archeological 3D Mapping: The Structure from Motion Revolution

Mapping is a critical aspect of systematic documentation no matter where archaeologists work. From hand-drawn maps of excavation units to maps created with Total Data Stations or LiDAR scanning, today’s archaeologists have a suite of mapping techniques and technologies to choose from when documenting a site. Typically, spectacular sites often receive high resolution mapping, whereas everyday sites rarely do. Recently, however, a revolutionary technology and technique has been created that can produce highly accurate and precise three-dimensional maps and orthophotos of archaeological sites, features, and profiles at a fraction of the cost and time of LiDAR and intensive TDS mapping: Structure from Motion (SfM). SfM is a new digital photography processing technique for capturing highly detailed, three-dimensional (3D) data from almost any surface using digital cameras. This article introduces the various platforms SfM photographs can be collected from (UAV, kites, balloons, poles, and groundbased) and provides examples of different types of data SfM can provide. The Structure from Motion Revolution is unfolding across the globe at a rapid pace, and we encourage archaeologists to take advantage of this new recording method

Alemtuzumab-induced remission of multiple sclerosis-associated uveitis

Purpose The purpose of the study was to report a case of multiple sclerosis (MS)-associated uveitis refractory to conventional immunosuppressants, with subsequent remission following treatment with alemtuzumab. Methods Case report Patient was treated with intravenous alemtuzumab, a lymphocyte depleting anti-CD52 monoclonal antibody that has recently been approved for use in relapsing MS. Results A 17-year-old female presented with bilateral optic neuritis and subsequently bilateral intermediate uveitis and secondary macular oedema. She was diagnosed with active relapsing MS for which she received treatment with alemtuzumab. The intraocular inflammation previously refractory to conventional immunosuppressants responded to alemtuzumab, inducing remission. Conclusions To our knowledge, this is the first such report of alemtuzumab treatment in MS-associated ocular inflammatory disease and may demonstrate a potential utility for this drug in related conditions

Time-Course Analysis of Gene Expression During the Saccharomyces cerevisiae Hypoxic Response

Many cells experience hypoxia, or low oxygen, and respond by dramatically altering gene expression. In the yeast Saccharomyces cerevisiae, genes that respond are required for many oxygen-dependent cellular processes, such as respiration, biosynthesis, and redox regulation. To more fully characterize the global response to hypoxia, we exposed yeast to hypoxic conditions, extracted RNA at different times, and performed RNA sequencing (RNA-seq) analysis. Time-course statistical analysis revealed hundreds of genes that changed expression by up to 550-fold. The genes responded with varying kinetics suggesting that multiple regulatory pathways are involved. We identified most known oxygen-regulated genes and also uncovered new regulated genes. Reverse transcription-quantitative PCR (RT-qPCR) analysis confirmed that the lysine methyltransferase EFM6 and the recombinase DMC1, both conserved in humans, are indeed oxygen-responsive. Looking more broadly, oxygen-regulated genes participate in expected processes like respiration and lipid metabolism, but also in unexpected processes like amino acid and vitamin metabolism. Using principle component analysis, we discovered that the hypoxic response largely occurs during the first 2 hr and then a new steady-state expression state is achieved. Moreover, we show that the oxygen-dependent genes are not part of the previously described environmental stress response (ESR) consisting of genes that respond to diverse types of stress. While hypoxia appears to cause a transient stress, the hypoxic response is mostly characterized by a transition to a new state of gene expression. In summary, our results reveal that hypoxia causes widespread and complex changes in gene expression to prepare the cell to function with little or no oxygen

Drivers of the changing abundance of European birds at two spatial scales

Detecting biodiversity change and identifying its causes is challenging because biodiversity is multifaceted and temporal data often contain bias. Here, we model temporal change in species' abundance and biomass by using extensive data describing the population sizes and trends of native breeding birds in the United Kingdom (UK) and the European Union (EU). In addition, we explore how species’ population trends vary with species’ traits. We demonstrate significant change in the bird assemblages of the UK and EU, with substantial reductions in overall bird abundance and losses concentrated in a relatively small number of abundant and smaller sized species. In contrast, rarer and larger birds had generally fared better. Simultaneously, overall avian biomass had increased very slightly in the UK and was stable in the EU, indicating a change in community structure. Abundance trends across species were positively correlated with species’ body mass and with trends in climate suitability, and varied with species’ abundance, migration strategy, and niche associations linked to diet. Our work highlights how changes in biodiversity cannot be captured easily by a single number; care is required when measuring and interpreting biodiversity change given that different metrics can provide very different insight

Climate vulnerability assessment for Pacific salmon and steelhead in the California Current Large Marine Ecosystem.

Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all anadromous Pacific salmon and steelhead (Oncorhynchus spp.) population units listed under the U.S. Endangered Species Act. Using an expert-based scoring system, we ranked 20 attributes for the 28 listed units and 5 additional units. Attributes captured biological sensitivity, or the strength of linkages between each listing unit and the present climate; climate exposure, or the magnitude of projected change in local environmental conditions; and adaptive capacity, or the ability to modify phenotypes to cope with new climatic conditions. Each listing unit was then assigned one of four vulnerability categories. Units ranked most vulnerable overall were Chinook (O. tshawytscha) in the California Central Valley, coho (O. kisutch) in California and southern Oregon, sockeye (O. nerka) in the Snake River Basin, and spring-run Chinook in the interior Columbia and Willamette River Basins. We identified units with similar vulnerability profiles using a hierarchical cluster analysis. Life history characteristics, especially freshwater and estuary residence times, interplayed with gradations in exposure from south to north and from coastal to interior regions to generate landscape-level patterns within each species. Nearly all listing units faced high exposures to projected increases in stream temperature, sea surface temperature, and ocean acidification, but other aspects of exposure peaked in particular regions. Anthropogenic factors, especially migration barriers, habitat degradation, and hatchery influence, have reduced the adaptive capacity of most steelhead and salmon populations. Enhancing adaptive capacity is essential to mitigate for the increasing threat of climate change. Collectively, these results provide a framework to support recovery planning that considers climate impacts on the majority of West Coast anadromous salmonids

3C236: Radio Source, Interrupted?

We present new HST STIS/MAMA near-UV images and archival WFPC2 V and R band images which reveal the presence of four star forming regions in an arc along the edge of the dust lane in the giant (4 Mpc) radio galaxy 3C236. Two of the star forming regions are relatively young with ages of order 1E7 yr, while the other two are older with ages of order 1E8 - 1E9 yr which is comparable to the estimated age of the giant radio source. Based on dynamical and spectral aging arguments, we suggest that the fuel supply to the AGN was interrupted for 1E7 yr and has now been restored, resulting in the formation of the inner 2 kpc scale radio source. This time scale is similar to that of the age of the youngest of the star forming regions. We suggest that the transport of gas in the disk is non-steady and that this produces both the multiple episodes of star formation in the disk as well as the multiple epochs of radio source activity. If the inner radio source and the youngest star forming region are related by the same event of gas transport, the gas must be transported from the hundreds of pc scale to the sub-parsec scale on a time scale of 1E7 yr, which is similar to the dynamical time scale of the gas on the hundreds of pc scales

Cellular, molecular and functional characterisation of YAC transgenic mouse models of Friedreich Ataxia

Copyright © 2014 Anjomani Virmouni et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Background - Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder, caused by a GAA repeat expansion mutation within intron 1 of the FXN gene. We have previously established and performed preliminary characterisation of several human FXN yeast artificial chromosome (YAC) transgenic FRDA mouse models containing GAA repeat expansions, Y47R (9 GAA repeats), YG8R (90 and 190 GAA repeats) and YG22R (190 GAA repeats). Methodology/Principal Findings - We now report extended cellular, molecular and functional characterisation of these FXN YAC transgenic mouse models. FXN transgene copy number analysis of the FRDA mice demonstrated that the YG22R and Y47R lines each have a single copy of the FXN transgene while the YG8R line has two copies. Single integration sites of all transgenes were confirmed by fluorescence in situ hybridisation (FISH) analysis of metaphase and interphase chromosomes. We identified significant functional deficits, together with a degree of glucose intolerance and insulin hypersensitivity, in YG8R and YG22R FRDA mice compared to Y47R and wild-type control mice. We also confirmed increased somatic GAA repeat instability in the cerebellum and brain of YG22R and YG8R mice, together with significantly reduced levels of FXN mRNA and protein in the brain and liver of YG8R and YG22R compared to Y47R. Conclusions/Significance - Together these studies provide a detailed characterisation of our GAA repeat expansion-based YAC transgenic FRDA mouse models that will help investigations of FRDA disease mechanisms and therapy.European Union, Ataxia UK and FARA