Increased Energy Differentially Increases Richness and Abundance of Optimal Body Sizes in Deep-Sea Wood-Falls

Theoretical and empirical studies suggest that the total energy available in natural communities influences body size as well as patterns of abundance and diversity. But the precise mechanisms underlying relationships or how these three ecological properties relate remain elusive. We identify five hypotheses relating energy availability, body size distributions, abundance, and species richness within communities, and we use experimental deep sea wood fall communities to test their predicted effects both on descriptors describing the species richness-body size distribution, and on trends in species richness within size classes over an energy gradient (size class-richness relationships). Invertebrate communities were taxonomically identified, weighed, and counted from 32 Acacia sp. logs ranging in size from 0.6 to 20.6 kg (corresponding to different levels of energy available) which were deployed at 3203 m in the Northeast Pacific Ocean for between 5 and 7 years. Trends in both the species richness-body size distribution and the size class-richness distribution with increasing wood fall size provide support for the Increased Packing hypothesis: species richness increases with increasing wood fall size but only in the modal size class. Furthermore, species richness of body size classes reflected the abundance of individuals in that size class. Thus, increases in richness in the modal size class with increasing energy were concordant with increases in abundance within that size class. The results suggest that increases in species richness occurring as energy availability increases may be isolated to specific niches, e.g. the body size classes, especially in communities developing on discrete and energetically isolated resources such as deep sea wood falls

Projected pH reductions by 2100 might put deep North Atlantic biodiversity at risk

This study aims to evaluate the potential for impacts of ocean acidification on North Atlantic deep-sea ecosystems in response to IPCC AR5 Representative Concentration Pathways (RCPs). Deep-sea biota is likely highly vulnerable to changes in seawater chemistry and sensitive to moderate excursions in pH. Here we show, from seven fully coupled Earth system models, that for three out of four RCPs over 17% of the seafloor area below 500 m depth in the North Atlantic sector will experience pH reductions exceeding ?0.2 units by 2100. Increased stratification in response to climate change partially alleviates the impact of ocean acidification on deep benthic environments. We report on major pH reductions over the deep North Atlantic seafloor (depth >500 m) and at important deep-sea features, such as seamounts and canyons. By 2100, and under the high CO2 scenario RCP8.5, pH reductions exceeding ?0.2 (?0.3) units are projected in close to 23% (~15%) of North Atlantic deep-sea canyons and ~8% (3%) of seamounts – including seamounts proposed as sites of marine protected areas. The spatial pattern of impacts reflects the depth of the pH perturbation and does not scale linearly with atmospheric CO2 concentration. Impacts may cause negative changes of the same magnitude or exceeding the current target of 10% of preservation of marine biomes set by the convention on biological diversity, implying that ocean acidification may offset benefits from conservation/management strategies relying on the regulation of resource exploitation

A mobile mapping system for hazardous facilities

The Mobile Mapping System (MMS) is a completely self-contained vehicle with omnidirectional capability and extremely good odometry, capable of operation up to 12 hours between battery charges. The platform itself is based on a dual differential drive system with a compliant linkage between the two drive systems. This compliant linkage allows for low-level controller errors to be absorbed by the system and their navigational effects to be compensated for, yielding an extremely accurate navigational capability. Vehicle design also allows for a considerable payload (250 lb) and a large surface area for auxiliary equipment mounting (2 by 6 ft). The vehicle supports remote operation by reading commands and writing replies through its serial communications port. Use of a radio-ethernet and a radio-video channel allow for remote video and communications links to be maintained with the vehicle in many remote operation environments. The MMS uses a structured light system to quickly acquire coarse range images of the environment and a coherent laser radar (CLR) to acquire finer resolution range images. The coherent laser radar can also be used to determine platform position and orientation to millimeter accuracies if targets of known. Sensor range image data as well as video are off loaded to a remote computer for postprocessing, display, and archiving. Diagrams and images below include an image of the MMS vehicle before addition of sensors, diagram of vehicle with sensors, and computer system connections

Effect of feeding single-dam or pooled colostrum on maternally derived immunity in dairy calves

peer-reviewedThe role of colostrum management in providing adequate immunological protection to neonatal calves has been widely investigated, and thresholds for colostrum quality, as well as optimum volume and timing for colostrum feeding have been established. However, limited information is available on the effect of colostrum source (single dam or pooled) on passive immunity, as well as subsequent antibody survival in the calf. This study aimed to assess the effect of feeding single-dam colostrum (own and other dam) or pooled colostrum on transfer of passive immunity, and also investigate the rate of depletion of disease-specific antibodies among dairy calves. In total, 320 cows and 119 dairy heifer calves were enrolled in the study. Calves were blood-sampled immediately after birth and received either own-dam, other-dam, or pooled colostrum. Calves were blood-sampled at 24 h to assess serum IgG concentrations and at monthly intervals thereafter to document disease-specific antibody survival. Mean colostrum IgG concentration was higher for other-dam treatment group, whereas own-dam and pooled treatments were similar. For all treatment groups, the mean IgG concentration was >80 mg/mL, exceeding the quality threshold of 50 mg/mL. Mean calf serum IgG concentration was lower for calves fed pooled colostrum compared with those that received colostrum from a single cow. There was a negative association with 24-h serum IgG and calf birth bodyweight; calves <30 kg at birth had the highest 24-h serum IgG concentration. Survival of antibodies to bovine viral diarrhea, Salmonella infection, leptospirosis, bovine parainfluenza 3 virus, bovine respiratory syncytical virus, rotavirus, and coronavirus was not associated with colostrum source; however, antibodies to infectious bovine rhinotracheitis had a greater period of survival among calves fed own-dam colostrum. We found that feeding single-dam colostrum can thus improve calf immunity through increased serum IgG levels and antibody survival rates. Furthermore, we hypothesize that immune exclusion may occur with pooled colostrum; therefore, providing pooled colostrum may still be a good practice as long as it can be ensured that enough antibodies are absorbed into the blood stream to deal with pathogens calves may encounter because different dams may have antibodies against different strains of viruses and bacteria, yielding cross protection

The response of nematodes to deep-sea CO2 sequestration : a quantile regression approach

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 57 (2010): 696-707, doi:10.1016/j.dsr.2010.03.003.One proposed approach to ameliorate the effects of global warming is sequestration of the greenhouse gas CO2 in the deep sea. To evaluate the environmental impact of this approach, we exposed the sediment-dwelling fauna at the mouth of the Monterey Submarine Canyon (3262 m) and a site on the nearby continental rise (3607 m) to CO2- rich water. We measured meiobenthic nematode population and community metrics after ~30-day exposures along a distance gradient from the CO2 source and with sediment depth to infer the patterns of mortality. We also compared the nematode response with that of harpacticoid copepods. Nematode abundance, average sediment depth, tail-group composition, and length: width ratio did not vary with distance from the CO2 source. However, quantile regression showed that nematode length and diameter increased in close proximity to the CO2 source in both experiments. Further, the effects of CO2 exposure and sediment depth (nematodes became more slender at one site, but larger at the other, with increasing depth in the sediment) varied with body size. For example, the response of the longest nematodes differed from those of average length. We propose that nematode body length and diameter increases were induced by lethal exposure to CO2-rich water and that nematodes experienced a high rate of mortality in both experiments. In contrast, copepods experienced high mortality rates in only one experiment suggesting that CO2 sequestration effects are taxon specific.The Department of Energy Office of Biological and Environmental Research supported this research under award numbers DE‐FG02‐05ER64070 and DE‐FG03‐01ER63065 and the U.S. Department of Energy, Fossil Energy Group (award DE‐FC26‐00NT40929). We also appreciate significant support provided by the Monterey Bay Aquarium Research Institute (project 200002)

Warm Dark Matter from keVins

We propose a simple model for Warm Dark Matter (WDM) in which two fermions are added to the Standard Model: (quasi-) stable "keVins" (keV inert fermions) which account for WDM and their unstable brothers, the "GeVins" (GeV inert fermions), both of which carry zero electric charge and lepton number, and are (approximately) "inert", in the sense that their only interactions are via suppressed couplings to the Z. We consider scenarios in which stable keVins are thermally produced and their abundance is subsequently diluted by entropy production from the decays of the heavier unstable GeVins. This mechanism could be implemented in a wide variety of models, including E_6 inspired supersymmetric models or models involving sterile neutrinos.Comment: 32 pages, 9 figures, 2 table

Measurement of νˉμ\bar{\nu}_{\mu} and νμ\nu_{\mu} charged current inclusive cross sections and their ratio with the T2K off-axis near detector

We report a measurement of cross section $\sigma(\nu_{\mu}+{\rm nucleus}\rightarrow\mu^{-}+X)$ and the first measurements of the cross section $\sigma(\bar{\nu}_{\mu}+{\rm nucleus}\rightarrow\mu^{+}+X)$ and their ratio $R(\frac{\sigma(\bar \nu)}{\sigma(\nu)})$ at (anti-)neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K $\bar{\nu}/\nu$-flux, for the detector target material (mainly Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory frame kinematics of $\theta_{\mu}$500 MeV/c. The results are $\sigma(\bar{\nu})=\left( 0.900\pm0.029{\rm (stat.)}\pm0.088{\rm (syst.)}\right)\times10^{-39}$ and $\sigma(\nu)=\left( 2.41\ \pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}$in units of cm$^{2}$/nucleon and$R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)= 0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure

Role of hydrogen sulfide in paramyxovirus infections

Hydrogen sulfide (H2S) is an endogenous gaseous mediator that has gained increasing recognition as an important player in modulating acute and chronic inflammatory diseases. However, its role in virus-induced lung inflammation is currently unknown. Respiratory syncytial virus (RSV) is a major cause of upper and lower respiratory tract infections in children for which no vaccine or effective treatment is available. Using the slow-releasing H2S donor GYY4137 and propargylglycin (PAG), an inhibitor of cystathionine-γ-lyase (CSE), a key enzyme that produces intracellular H2S, we found that RSV infection led to a reduced ability to generate and maintain intracellular H2S levels in airway epithelial cells (AECs). Inhibition of CSE with PAG resulted in increased viral replication and chemokine secretion. On the other hand, treatment of AECs with the H2S donor GYY4137 reduced proinflammatory mediator production and significantly reduced viral replication, even when administered several hours after viral absorption. GYY4137 also significantly reduced replication and inflammatory chemokine production induced by human metapneumovirus (hMPV) and Nipah virus (NiV), suggesting a broad inhibitory effect of H2S on paramyxovirus infections. GYY4137 treatment had no effect on RSV genome replication or viral mRNA and protein synthesis, but it inhibited syncytium formation and virus assembly/release. GYY4137 inhibition of proinflammatory gene expression occurred by modulation of the activation of the key transcription factors nuclear factor κB (NF-κB) and interfero