Calcite production by Coccolithophores in the South East Pacific Ocean: from desert to jungle

International audienceBIOSOPE cruise achieved an oceanographic transect from the Marquise Islands to the Peru-Chili upwelling (PCU) via the centre of the South Pacific Gyre (SPG). Water samples from 6 depths in the euphotic zone were collected at 20 stations. The concentrations of suspended calcite particles, coccolithophores cells and detached coccoliths were estimated together with size and weight using an automatic polarizing microscope, a digital camera, and a collection of softwares performing morphometry and pattern recognition. Some of these softwares are new and described here for the first time. The coccolithophores standing stocks are usually low and reach maxima west of the PCU. The coccoliths of Emiliania huxleyi, Gephyrocapsa spp. and Crenalithus spp. (Order Isochrysidales) represent 50% of all the suspended calcite particles detected in the size range 0.1–46 µm (21% of PIC in term of the calcite weight). The latter species are found to grow preferentially in the Chlorophyll maximum zone. In the SPG their maximum concentrations was found to occur between 150 and 200 m, which is very deep for these taxa. The weight and size of coccoliths and coccospheres are correlated. Large and heavy coccoliths and coccospheres are found in the regions with relative higher fertility in the Marquises Island and in the PCU. Small and light coccoliths and coccospheres are found west of the PCU. This distribution may correspond to that of the concentration of calcium and carbonate ions

Prevention in the age of personal responsibility: epigenetic risk-predictive screening for female cancers as a case study

Epigenetic markers could potentially be used for risk assessment in risk-stratified population-based cancer screening programmes. Whereas current screening programmes generally aim to detect existing cancer, epigenetic markers could be used to provide risk estimates for not-yet-existing cancers. Epigenetic risk-predictive tests may thus allow for new opportunities for risk assessment for developing cancer in the future. Since epigenetic changes are presumed to be modifiable, preventive measures, such as lifestyle modification, could be used to reduce the risk of cancer. Moreover, epigenetic markers might be used to monitor the response to risk-reducing interventions. In this article, we address ethical concerns related to personal responsibility raised by epigenetic risk-predictive tests in cancer population screening. Will individuals increasingly be held responsible for their health, that is, will they be held accountable for bad health outcomes? Will they be blamed or subject to moral sanctions? We will illustrate these ethical concerns by means of a Europe-wide research programme that develops an epigenetic risk-predictive test for female cancers. Subsequently, we investigate when we can hold someone responsible for her actions. We argue that the standard conception of personal responsibility does not provide an appropriate framework to address these concerns. A different, prospective account of responsibility meets part of our concerns, that is, concerns about inequality of opportunities, but does not meet all our concerns about personal responsibility. We argue that even if someone is responsible on grounds of a negative and/or prospective account of responsibility, there may be moral and practical reasons to abstain from moral sanctions

Assessment of pain symptoms and quality of life using the International Spinal Cord Injury Data Sets in persons with chronic spinal cord injury

Introduction: Traumatic spinal cord injury (SCI) triggers complex changes that can negatively impact health and quality of life. The International SCI Data Sets were developed to enable more comparable data collection on the complex sequelae of SCI across studies. This should facilitate progress in mechanistic understanding and improving treatments of SCI. Study design: Prospective observational pilot study. Objectives: To collect data on pain symptoms and quality of life (QoL) in adults living with chronic SCI. Setting: Academic medical center, New York, USA. Methods: The International SCI Basic Pain and Qol Data Sets were used to collect data from participants with chronic SCI (N = 31) at 2 study visits held 6 months apart. The QoL Data Set was also used to collect data from able-bodied persons of similar age and gender distribution (N = 28). Results: Most participants with SCI had multiple types and locations of pain problems at both study visits, despite reported being treated for pain. At both visits, the worst pain problem type was nociceptive, followed by neuropathic, which was typically rated of higher intensity. QoL scores were significantly lower across all domains of the data set in persons with SCI than able-bodied persons. Persons with pain tended to have lower QoL scores, although this trend was not significant. Conclusions: This study demonstrates the presence, complexity and stability of pain symptoms refractory to treatment and lower quality of life ratings in persons with chronic SCI. Sponsorship: Grants from the Craig H. Neilsen Foundation, New York Empire Clinical Research Program, New York State Spinal Cord Injury Research Board

Influence of stoichiometry and structure on the optical properties of AlNxOy films

The AlNxOy system offers the possibility to obtain a wide range of responses, by tailoring the properties between Al, AlN and Al2O3, opening a significant number of possible applications. The aim of this work is to correlate the optical properties of AlNxOy thin films with their composition and structural features, taking as reference the binary systems AlNx and AlOy. In the AlNx system, the increase of the nitrogen content induced a wide variation in the optical properties, ranging from the typical profile of a polycrystalline Al-type film towards nearly constant reflectance values as low as 5%, as well as a smooth increase in samples transparency as the ratio N/Al approached unit. In the case of the AlOy system, the reflectance also decreased as the oxygen content increased, however the transition to transparent films (Al2O3-like) was more abrupt. The ternary system AlNxOy, revealed optical responses that ranged from a typical profile of a polycrystalline Al-type film, towards low and constant reflectance values in a wide range of x and y coefficients, ending up as semi-transparent when Al2O3-like films were formed. The unusual low optical reflectance of some films reveals some potential applications in solar power systems and sensors.This research is sponsored by FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividade, by national funds through FCT,, under the projects PTDC/CTMNAN/ 112574/2009 and PEST-C-FIS/UI607/2011–2012, and Programa Pessoa 2010/2011—Cooperação Portugal/França, Proc. no 441.00, Project ‘COLOURCLUSTER’. J Borges also acknowledges FCT financial support under PhD grant no SFRH/BD/47118/200

Dark Matter Directionality Detection performance of the Micromegas-based μ\muTPC-MIMAC detector

Directional Dark Matter Detection (DDMD) can open a new signature for Weakly Massive Interacting Particles (WIMPs) Dark Matter. The directional signature provides in addition, an unique way to overcome the neutron and neutrino backgrounds. In order to get the directional signature, the DDM detectors should be sensitive to low nuclear energy recoils in the keV range and have an angular resolution better than $20^{\circ}$. We have performed experiments with low energy ($<30\,\mathrm{keV}$) ion beam facilities to measure the angular distribution of nuclear recoil tracks in a MIMAC detector prototype. In this paper, we study angular spreads with respect to the electron drift direction ($0^{\circ}$ incident angle) of Fluorine nuclear tracks in this low energy range, and show nuclear recoil angle reconstruction produced by a monoenergetic neutron field experiment. We find that a high-gain systematic effect leads to a high angular resolution along the electron drift direction. The measured angular distribution is impacted by diffusion, and space charge or ion feedback effects, which can be corrected for by an asymmetry factor observed in the flash-ADC profile. The estimated angular resolution of the $0^{\circ}$ incident ion is better than $15^{\circ}$ at $10$ keV kinetic energy and agrees with the simulations within $20$%. The distributions from the nuclear recoils have been compared with simulated results based on a modified Garfield++ code. Our study shows that protons would be a more adapted target than heavier nuclei for DDMD of light WIMPs. We demonstrate that directional signature from the Galactic halo origin of a Dark Matter WIMP signal is experimentally achievable, with a deep understanding of the operating conditions of a low pressure detector with its diffusion mechanism.Comment: 19 pages, 12 figure

Calcification response of a key phytoplankton family to millennial-scale environmental change

Coccolithophores are single-celled photosynthesizing marine algae, responsible for half of the calcification in the surface ocean, and exert a strong influence on the distribution of carbon among global reservoirs, and thus Earth’s climate. Calcification in the surface ocean decreases the buffering capacity of seawater for CO2, whilst photosynthetic carbon fixation has the opposite effect. Experiments in culture have suggested that coccolithophore calcification decreases under high CO2 concentrations ([CO2(aq)]) constituting a negative feedback. However, the extent to which these results are representative of natural populations, and of the response over more than a few hundred generations is unclear. Here we describe and apply a novel rationale for size-normalizing the mass of the calcite plates produced by the most abundant family of coccolithophores, the Noëlaerhabdaceae. On average, ancient populations subjected to coupled gradual increases in [CO2(aq)] and temperature over a few million generations in a natural environment become relatively more highly calcified, implying a positive climatic feedback. We hypothesize that this is the result of selection manifest in natural populations over millennial timescales, so has necessarily eluded laboratory experiments

Electrical properties of AlNxOy thin films prepared by reactive magnetron sputtering

Direct current magnetron sputtering was used to produce AlNxOy thin films, using an aluminum target, argon and a mixture of N2+O2 (17:3) as reactive gases. The partial pressure of the reactive gas mixture was increased, maintaining the discharge current constant. Within the two identified regimes of the target (metallic and compound), four different tendencies for the deposition rate were found and a morphological evolution from columnar towards cauliflower-type, ending up as dense and featureless-type films. The structure was found to be Al-type (face centered cubic) and the structural characterization carried out by X-ray 2 diffraction and transmission electron microscopy suggested the formation of an aluminumbased polycrystalline phase dispersed in an amorphous aluminum oxide/nitride (or oxynitride) matrix. This type of structure, composition, morphology and grain size, were found to be strongly correlated with the electrical response of the films, which showed a gradual transition between metallic-like responses towards semiconducting and even insulating-type behaviors. A group of films with high aluminum content revealed a sharp decrease of the temperature coefficient of resistance (TCR) as the concentration ratio of non-metallic/aluminum atomic ratio increased. Another group of samples, where the non-metallic content became more important, revealed a smooth transition between positive and negative values of TCR. In order to test whether the oxynitride films have a unique behavior or simply a transition between the typical responses of aluminum and of those of the correspondent nitride and oxide, the electrical properties of the ternary oxynitride system were compared with AlNx and AlOy systems, prepared in similar conditions.This research is sponsored by FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividade, by the national funds through FCT-Fundação para a Ciência e a Tecnologia, under the project PTDC/CTM-NAN/112574/2009 and Programa Pessoa 2010/2011 Cooperação Portugal/França, Proc.º 441.00, Project“COLOURCLUSTER”. J. Borges also acknowledges FCT financial support under PhD grant no. SFRH/BD/47118/2008

A Description of Clinician Reported Diagnosis of Type 2 Diabetes and Other Non-Type 1 Diabetes Included in a Large International Multicentered Pediatric Diabetes Registry (SWEET)

Although type 1 diabetes (T1D) remains the most frequent form of diabetes in individuals aged less than 20 years at onset, other forms of diabetes are being increasingly recognized.info:eu-repo/semantics/publishedVersio

Calcification response of a key phytoplankton family to millennial-scale environmental change

Coccolithophores are single-celled photosynthesizing marine algae, responsible for half of the calcification in the surface ocean, and exert a strong influence on the distribution of carbon among global reservoirs, and thus Earth’s climate. Calcification in the surface ocean decreases the buffering capacity of seawater for CO2, whilst photosynthetic carbon fixation has the opposite effect. Experiments in culture have suggested that coccolithophore calcification decreases under high CO2 concentrations ([CO2(aq)]) constituting a negative feedback. However, the extent to which these results are representative of natural populations, and of the response over more than a few hundred generations is unclear. Here we describe and apply a novel rationale for size-normalizing the mass of the calcite plates produced by the most abundant family of coccolithophores, the Noëlaerhabdaceae. On average, ancient populations subjected to coupled gradual increases in [CO2(aq)] and temperature over a few million generations in a natural environment become relatively more highly calcified, implying a positive climatic feedback. We hypothesize that this is the result of selection manifest in natural populations over millennial timescales, so has necessarily eluded laboratory experiments.HLOM was funded by PhD studentship NE/I019522/1 in association with UKOARP. REMR acknowledges NERC grant NE/H017119/1 and ERC grant SP2-GA-2008-200915. LB is grateful for financial support from EU Seventh Framework program Past4Future and from the Agence Nationale de la Recherche under project ANR-12-B06-0007 (CALHIS). PF was funded by Marie-Curie Reintegration grant (PERG-GA-2010-272134 - MILLEVARIABILI), funded by the EU PNRA 2013/AZ2.06 and GEOSMART, funded by the Italian National Antarctic Research Programme

Influence of phyllosilicate mineral assemblages, fabrics, and fluids on the behavior of the Punchbowl fault, southern California

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95206/1/jgrb13457.pd