Benthic marine calcifiers coexist with CaCO3-undersaturated seawater worldwide

Ocean acidification and decreasing seawater saturation state with respect to calcium carbonate (CaCO3) minerals have raised concerns about the consequences to marine organisms, especially those building structures made of CaCO3. A large proportion of benthic marine calcifiers incorporate Mg2+ into their calcareous structures (i.e., Mg-calcite) which, in general, reduces mineral stability. The vulnerability of some marine calcifiers to ocean acidification is related to the solubility of their calcareous structures, but not all marine organisms conform to this because of sophisticated biological and physiological mechanisms to construct and maintain CaCO3 structures. Few studies have considered seawater saturation state with respect to species-specific mineralogy in evaluating the effect of ocean acidification on marine organisms. Here, a global dataset of skeletal mol % MgCO3 of benthic calcifiers and in situ environmental conditions (temperature, salinity, pressure, and [CO32-]) spanning a depth range of 0 m (subtidal/neritic) to 5500 m (abyssal) was assembled to calculate in situ seawater saturation states with respect to species-specific Mg-calcite mineral compositions (?Mg-x). Up to 20% of all studied calcifiers at depths 1200 m currently experience seawater mineral undersaturation with respect to their skeletal mineral phase (?Mg-x1200 m) of all studied calcifying species to seawater undersaturation. These observations underscore concerns over the ability of marine benthic calcifiers to continue to construct and maintain their calcareous structures under these conditions. We advocate that ocean acidification tipping points can only be understood by assessing species-specific responses, and because of different seawater ?Mg-x present in all marine ecosystems

Spin induced multipole moments for the gravitational wave flux from binary inspirals to third Post-Newtonian order

Using effective field theory techniques we calculate the source multipole moments needed to obtain the spin contributions to the power radiated in gravitational waves from inspiralling compact binaries to third Post-Newtonian order (3PN). The multipoles depend linearly and quadratically on the spins and include both spin(1)spin(2) and spin(1)spin(1) components. The results in this paper provide the last missing ingredient required to determine the phase evolution to 3PN including all spin effects which we will report in a separate paper.Comment: 35 pages, 7 figures. Published versio

Benthic marine calcifiers coexist with CaCO3-undersaturated seawater worldwide

Ocean acidification and decreasing seawater saturation state with respect to calcium carbonate (CaCO3) minerals have raised concerns about the consequences to marine organisms, especially those building structures made of CaCO3. A large proportion of benthic marine calcifiers incorporate Mg2+ into their calcareous structures (i.e., Mg-calcite) which, in general, reduces mineral stability. The vulnerability of some marine calcifiers to ocean acidification is related to the solubility of their calcareous structures, but not all marine organisms conform to this because of sophisticated biological and physiological mechanisms to construct and maintain CaCO3 structures. Few studies have considered seawater saturation state with respect to species-specific mineralogy in evaluating the effect of ocean acidification on marine organisms. Here, a global dataset of skeletal mol % MgCO3 of benthic calcifiers and in situ environmental conditions (temperature, salinity, pressure, and [CO32-]) spanning a depth range of 0 m (subtidal/neritic) to 5500 m (abyssal) was assembled to calculate in situ seawater saturation states with respect to species-specific Mg-calcite mineral compositions (?Mg-x). Up to 20% of all studied calcifiers at depths <1200 m and approximately 90% of calcifiers at depths >1200 m currently experience seawater mineral undersaturation with respect to their skeletal mineral phase (?Mg-x<1). We conclude that as a result of predicted anthropogenic ocean acidification over the next 150 years, the predicted decrease in seawater mineral saturation, will expose approximately 50% (<1200 m) and 100% (>1200 m) of all studied calcifying species to seawater undersaturation. These observations underscore concerns over the ability of marine benthic calcifiers to continue to construct and maintain their calcareous structures under these conditions. We advocate that ocean acidification tipping points can only be understood by assessing species-specific responses, and because of different seawater ?Mg-x present in all marine ecosystems

Dynamics of ions in the selectivity filter of the KcsA channel

The statistical and dynamical properties of ions in the selectivity filter of the KcsA ion channel are considered on the basis of molecular dynamics (MD) simulations of the KcsA protein embedded in a lipid membrane surrounded by an ionic solution. A new approach to the derivation of a Brownian dynamics (BD) model of ion permeation through the filter is discussed, based on unbiased MD simulations. It is shown that depending on additional assumptions, ion’s dynamics can be described either by under-damped Langevin equation with constant damping and white noise or by Langevin equation with a fractional memory kernel. A comparison of the potential of the mean force derived from unbiased MD simulations with the potential produced by the umbrella sampling method demonstrates significant differences in these potentials. The origin of these differences is an open question that requires further clarifications

The relationship with feeding and urolithiasis in fattening bulls

U. Ü. Veteriner Faküilesi Pilot Besi Ünitesinde konsantre yemle beslenen 15 adet erkek esmer ırkı besi sığırlannda, böbrek taşı oluşumlan gözlendi. 8 ay süre ile yapılan besi sonunda kesilen hayvanlarda makros kopik ve histopatolojik olarak böbrek ve sidik kesesi muayene edilirken, bu hayvanlarda idrann kimyasal bileşimi ve taşinan içerigi incelendi. içtikleri suyun detaylı olarak analizi yapıldı. Saptanan taş oluşumunun kış aylarında içeren besi süresinde konsantre yemden kaynaklandığı saptandı.The külney stone fonnations were observed in 15 young fattening bulls, which were fed with concantrated feed in Uludag University Veterinary Educational and Research fann. At the end of feeding period for eight months, kidneys and vesica urinaries samples were examined macroscopically and histopatologically of slaughtered animals. Chemical compositions of urine and stones were also analyzed. Drinking water was analyzed in details. lt was concluded that stone fonnation was as a result of feeding of anima/s with concantrated feed

A comprehensive study of Antarctic algal symbioses: minimal impacts of endophyte presence in most species of macroalgal hosts

Many species of macroalgae along the western Antarctic Peninsula have a high coverage of filamentous algal endophytes. A previous field study showed that endophyte presence negatively impacts growth and survival in some Antarctic algae, but can have no impact on others. We examined nine species of common macroalgal hosts from the area surrounding Palmer Station, Antarctica, to examine fine-scale impacts of endophyte presence on host physiology. Physiological parameters were selected based on their potential to influence fitness of host algae. These included photosynthetic parameters, thallus toughness and susceptibility to grazers in those species previously known to be chemically defended. We found that few macroalgal hosts are impacted by the presence of endophytes and that these impacts are not consistent across all physiological parameters. Iridaea cordata and Pachymenia sp. were the only species among the nine examined that demonstrated physiological stress in the presence of endophytes. Out of four species in a previous study, I. cordata was also the most heavily impacted by endophyte presence