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Conservation and protection of marine mammals: past, present and future

first_imgThis paper reviews some of the major issues, programs and events that have led to the current state of marine mammal populations, management goals and management programs worldwide. It notes the changing focus of management issues and research needs during the past decade and attempts to forecast the kinds of research needed to deal with likely issues in the forthcoming decade.last_img

The effects of temperature and moisture on CO2 uptake and total resistance to water loss in the antarctic foliose lichen Umbilicaria antarctica

first_imgMaximum net photosynthesis of field‐fresh thalli, illuminated at 200 μmol photons m−2 s−1 (PAR), was attained at 13 °C and 1.10 g g−1 water content. Small but significant rates of photosynthesis were measured at −5.5 °C. Depression of net photosynthesis at high thallus water contents is explained in terms of thallus anatomy. Calculation of evaporative resistance of the thallus by a new method showed a moisture‐dependent response pattern, and was in agreement with direct observations made on other foliose species.last_img

Magmatic and tectonic patterns over the Northern Victoria Land sector of the Transantarctic Mountains from new aeromagnetic imaging

first_imgNew aeromagnetic data image the extent and spatial distribution of Cenozoic magmatism and older basement features over the Admiralty Block of the Transantarctic Mountains. Digital enhancement techniques image magmatic and tectonic features spanning in age front the Cambrian to the Neogene. Magnetic lineaments trace major fault zones, including NNW to NNE trending transtensional fault systems that appear to control the emplacement of Neogene age McMurdo volcanics. These faults represent splays front a major NW-SE oriented Cenozoic strike-slip fault belt, which reactivated the inherited early Paleozoic structural architecture. NE-SW oriented magnetic lineaments are also typical of the Admiralty Block and reflect post-Miocene age extensional faults. To re-investigate controversial relationships between strike-slip faulting, rifting, and Cenozoic magmatism, we combined the new aeromagnetic data with previous datasets over the Transantarctic Mountains and Ross Sea Rift. Two key observations can be made from Our aeromagnetic compilation: I) Cenozoic alkaline intrusions along the margin of the Ross Sea Rift lie oblique to the NW-SE strike-slip faults and are not significantly displaced by them; 2) the Southern Cross and the Admiralty Blocks are Much more significantly affected by Cenozoic magmatism compared to the adjacent tectonic blocks, thereby indicating major tectono-magmatic segmentation of the Transantarctic Mountains rift flank. We put forward three alternative tectonic models to explain the puzzling observation that major Cenozoic alkaline intrusions emplaced along the Ross Sea Rift margin show no evidence for major strike-slip displacement. Our first model predicts that the alkaline intrusions were emplaced along left-lateral cross-faults, which accommodated distributed right-lateral shearing. In contrast, our second model does not require major distributed strike-slip shearing, and relates the emplacement of Cenozoic alkaline intrusions to sea-floor spreading in the Adare Basin, Coupled with intracontinental transfer faulting. The third model is all attempt to reconcile the two opposing hypothesis and relies oil a recent inference, which postulates that opening of the Adare Basin relates to fault splaying front the Balleny strike-slip fault zone. A low seismic velocity anomaly in the upper mantle appears to extend from the Ross Sea Rift Under the Admiralty and Southern Cross Blocks of the Transantarctic Mountains. Lateral flow of [lot upper mantle from the rifted region to the rift flank may explain the observed tectono-magmatic segmentation of the Transantarctic Mountains. We infer that this process caused a regional upwarp of the Curie isotherm under the Admiralty and Southern Cross Blocks of the Transantarctic Mountains, and facilitated extensional faulting, renewed uplift, and volcanism in the Neogene. (C) 2008 Elsevier B.V. All rights reserved.last_img read more

Exploring Pandora’s Box: potential and pitfalls of low coverage genome surveys for evolutionary biology

first_imgHigh throughput sequencing technologies are revolutionizing genetic research. With this ‘‘rise of the machines’’, genomic sequences can be obtained even for unknown genomes within a short time and for reasonable costs. This has enabled evolutionary biologists studying genetically unexplored species to identify molecular markers or genomic regions of interest (e.g. micro- and minisatellites, mitochondrial and nuclear genes) by sequencing only a fraction of the genome. However, when using such datasets from non-model species, it is possible that DNA from non-target contaminant species such as bacteria, viruses, fungi, or other eukaryotic organisms may complicate the interpretation of the results. In this study weanalysed 14 genomic pyrosequencing libraries of aquatic non-model taxa from four major evolutionary lineages. Wequantified the amount of suitable micro- and minisatellites, mitochondrial genomes, known nuclear genes and transposable elements and searched for contamination from various sources using bioinformatic approaches. Our results show that in all sequence libraries with estimated coverage of about 0.02–25%, many appropriate micro- and minisatellites, mitochondrial gene sequences and nuclear genes from different KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways could be identified and characterized. These can serve as markers for phylogenetic and population genetic analyses. A central finding of our study is that several genomic libraries suffered from different biases owing to non-target DNA or mobile elements. Inparticular, viruses, bacteria or eukaryote endosymbionts contributed significantly (up to 10%) to some of the libraries analysed. If not identified as such, genetic markers developed from high-throughput sequencing data for non-model organisms may bias evolutionary studies or fail completely in experimental tests. In conclusion, our study demonstrates the enormous potential of low-coverage genome survey sequences and suggests bioinformatic analysis workflows. The results also advise a more sophisticated filtering for problematic sequences and non-target genome sequences prior to developing markers.last_img read more

Sea ice in the paleoclimate system: the challenge of reconstructing sea ice from proxies – an introduction

first_imgSea ice is an important component of the Earth system with complex dynamics imperfectly documented from direct observations, which are primarily limited to the last 40 years. Whereas large amplitude variations of sea ice have been recorded, especially in the Arctic, with a strikingly fast decrease in recent years partly attributed to the impact of anthropogenic climate changes, little is known about the natural variability of the sea ice cover at multi-decadal to multi-millennial time scales. Hence, there is a need to establish longer sea ice time series to document the full range of sea ice variations under natural forcings. To do this, several approaches based on biogenic or geochemical proxies have been developed from marine, ice core and coastal records. The status of the sea ice proxies has been discussed by the Sea Ice Proxy (SIP) working group endorsed by PAGES during a first workshop held at GEOTOP in Montréal. The present volume contains a set of papers addressing various sea ice proxies and their application to large scale sea ice reconstruction. Here we summarize the contents of the volume, including a table of various proxies available in marine sediments and ice cores, with their possibilities and limitations.last_img read more

Electron losses from the radiation belts caused by EMIC waves

first_imgElectromagnetic Ion Cyclotron (EMIC) waves cause electron loss in the radiation belts by resonating with high energy electrons at energies greater than about 500 keV. However, their effectiveness has not been fully quantified. Here we determine the effectiveness of EMIC waves by using wave data from the fluxgate magnetometer on CRRES to calculate bounce averaged pitch angle and energy diffusion rates for L* =3.5 – 7 for five levels of Kp between 12 – 18 MLT. To determine the electron loss EMIC diffusion rates were included in the BAS Radiation Belt Model together with whistler mode chorus, plasmaspheric hiss and radial diffusion. By simulating a 100 day period in 1990 we show that EMIC waves caused a significant reduction in the electron flux for energies greater than 2 MeV but only for pitch angles lower than about 60°.The simulations show that the distribution of electrons left behind in space looks like a pancake distribution. Since EMIC waves cannot remove electrons at all pitch angles even at 30 MeV, our results suggest that EMIC waves are unlikely to set an upper limit on the energy of the flux of radiation belt electrons.last_img read more

Serna pulls Rapids to a 2-2 tie against Real Salt Lake

first_img Written by July 22, 2018 /Sports News – Local Serna pulls Rapids to a 2-2 tie against Real Salt Lake Tags: MLS/Real Salt Lake/Soccer FacebookTwitterLinkedInEmailSALT LAKE CITY (AP) — Dillon Serna’s goal at the 88th minute lifted Colorado to a 2-2 tie against Real Salt Lake on Saturday in a match delayed 45 minutes by rain and lightning.Serna entered the game at the 85th minute and replaced Kortne Ford. Shortly thereafter, Colorado’s Edgar Castillo put together a run on the left side, weaved through Salt Lake defenders and fired a shot saved by Nick Rimando. Serna continued his run and from a difficult angle at left got the rebound past Rimando.Damir Kreilach scored in the 11th minute for Salt Lake (9-9-3) on a lunging header off a cross from Joao Plata. Six minutes later, Plata made it a 2-0 contest with his shot off a cross from Jefferson Savarino.Colorado (4-11-5) regrouped and Jack McBean scored on a penalty kick to make it 2-1 in the 33rd. Associated Presslast_img read more

BYU Women’s Volleyball Earns No. 4 Seed For NCAA Tournament

first_img Written by FacebookTwitterLinkedInEmailPROVO, Utah-Despite a disappointing 3-0 loss to Loyola Marymount to end the regular season, the highly successful BYU women’s volleyball team still earned a No. 4 seed in the upcoming NCAA Tournament as confirmed late Sunday evening when the bracket was released.The 27-1 Cougars will host Stony Brook, the champions of the America East Conference, Friday evening at 7:00 pm at the Smith Fieldhouse.The Seawolves come in with a record of 21-8. The Smith Fieldhouse also hosts the Utah Utes’ match against the Denver Pioneers at 4:00 pm Friday afternoon as the Cougars were selected to be the host team for this pod.This tournament berth commemorates the seventh consecutive season the vaunted Cougars’ volleyball team has qualified for the NCAA Tournament. This is the 31st overall berth in program history for BYU, the seventh-most for a program in NCAA women’s volleyball history.The Cougars have been the top-ranked team in 11 of this season’s 14 American Volleyball Coaches Association coaches’ polls by virtue of their 27-match winning streak.This saw the Cougars vanquish top overall seed Stanford, No. 14 seed Marquette and other Power 5 conference squads Duke, Syracuse, Utah and USC.Senior outside hitter Roni Jones-Perry has been BYU’s brightest star, as she has amassed 487 points on the season. Brad James Tags: America East/BYU Women’s Volleyball/Denver Pioneers/Duke/Loyola Marymount/Marquette/NCAA Tournament/Roni Jones-Perry/Stanford/Stony Brook/Syracuse/USC/Utah November 26, 2018 /Sports News – Local BYU Women’s Volleyball Earns No. 4 Seed For NCAA Tournamentlast_img read more

Huskies Slip Past Cougars in Game One

first_img Tags: BYU Cougars Baseball/Washington Huskies Casey Jacobsen hit a double with two outs in the third and Austin Deming and Brock Hale had leadoff singles in the fifth and seventh innings, respectively, but the Cougars couldn’t string together enough plays to score. Robert Lovell “Jordan (Wood) and Reid (McLaughlin) did a great job tonight,” BYU head coach Mike Littlewood said. “We couldn’t string together a few hits and we didn’t do a great job of executing offensively when we need to.” Casey Jacobsen: 1-3, 2BJordan Wood: 5.2 IP, 3 H, 0 ER, 8 K Written by Freshman Reid McLaughlin came on for BYU with the bases loaded and two outs in the sixth, striking out the Husky batter to get out of the jam. Coming in with the lowest ERA of any freshman in the nation at 1.54, McLaughlin retired the side in the seventh but a solo home run to left field with one out in the eighth gave Washington the win. BYU (24-10) and Washington (17-15) battled through seven innings scoreless as the Cougars’ Jordan Wood and the Huskies’ Jordan Jones kept bats on both sides at bay well into the game. Wood struck out a season-best eight in just under six innings, allowing three hits. Jones went six innings with five strikeouts, no walks and three hits.center_img Game Summary BYU and Washington will play again on Friday, April 19, at 6 p.m. PT. The game will stream online live on the Pac-12 Network, BYU Radio and ESPN 960 AM. April 18, 2019 /Sports News – Local Huskies Slip Past Cougars in Game One Player Highlights A solo home run by the Huskies in the bottom of the eighth was the difference in a rainy game that saw only seven combined hitsThe run was just the second earned run in the last 18 innings for BYU pitcher Reid McLaughlinBYU starting pitcher Jordan Wood had a season-high eight strikeouts, including inning-ending Ks with runners in scoring position in the third, fourth and fifth innings FacebookTwitterLinkedInEmailSEATTLE – One swing in the bottom of the eighth inning was all Washington needed to defeat BYU 1-0 in the series opener at Husky Ballpark on Thursday.last_img read more

Giants wide receiver Golden Tate suspended four games

first_img FacebookTwitterLinkedInEmailiStock(NEW YORK) — ESPN reports the NFL suspended New York Giants wide receiver Golden Tate for violating the league’s performance-enhancing substance policy.Tate is appealing the suspension, scheduled for Aug. 6. He claims the banned substance was prescribed as fertility medication.Tate released the following statement after the suspension was made public:“This past April, during the off-season, my wife and I decided to see a specialist for fertility planning. I started the treatment prescribed to me and just days later I discovered it contained an ingredient that is on the league’s banned substance list. I immediately discontinued use, I reported the situation to the Independent Administrator of the NFL Policy on Performance-Enhancing Substances, and I spoke with my coaches and general manager. I did all of this well before a failed test was even confirmed. Per NFL protocol, an initial suspension was imminent, but myself and the Giants organization are confident in the facts, and eagerly await my appeal to put this behind us.”ESPN’s Adam Schefter reports a resolution on the case is expected before the start of the regular season.Tate’s loss marks another blow to an already thin Giants receiving corps. After trading star wide receiver Odell Beckham Jr. to the Cleveland Browns this offseason, Giants receivers Corey Coleman and Sterling Shepard suffered injuries during the first week of training camp. Coleman will miss the season with a torn ACL, and Shepard is expected to miss significant time in training camp with a broken thumb.Tate signed a four-year, $37.5 million deal with the Giants this offseason. He is entering his eleventh NFL season, having previously played with Seattle, Detroit, and Philadelphia.Copyright © 2019, ABC Radio. All rights reserved. Beau Lund July 27, 2019 /Sports News – National Giants wide receiver Golden Tate suspended four gamescenter_img Written bylast_img read more