Category Archives: Past Projects

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Fujifilm X

Fuji vient de lever le voile sur le X M1, un appareil qui s’inscrit dans la lignée de la série X Premium de la marque. Le X100 avait introduit, avec un certain style, un viseur hybride et une prise en mains à l’ancienne. Le X Pro 1 avait poursuivi sur cette lancée, avant que le X E1 ne vienne réduire un peu la voilure. La visée se faisait désormais sur un viseur purement numérique. Le X M1 prend logiquement la suite du X M1 et supprime carrément le viseur. Plus abordable, plus "hybride", mais avec de sacrés arguments à faire valoir.

Plus abordable, le X M1 l’est certainement. Le haut de gamme, le X Pro1, se trouve autour des 1600 avec une optique, le X E1 s’affiche à 1400 ,
borse chanel, alors que le X100s est encore entre 1100 et 1200 . Avec le X M1, Fujifilm fait passer le ticket d’entrée de la série X à 799 avec le nouveau 16 50 mm annoncé aujourd’hui aussi, ou à 699 nu.

Mais au premier coup d’il, ce qui marque,
chanel 2.55 borse chanel 28600, c’est la différence d’ergonomie. Ici donc, plus de viseur hybride, ni même seulement électronique. La visée se fait par le seul biais de l’écran LCD, un modèle de 7,5 cm affichant 920 000 points (il était de 1,23 million de points sur le X Pro1), et inclinable. De même sur le dessus,
chanel 2.55 borse chanel a36097, les traditionnelles molettes contrôlant l’obturation et la compensation d’exposition font désormais placeà un sélecteur PSAM plus conventionnel.

Du coup, l’appareil est plus compact, gagnant presque 1 centimètre en hauteur par rapport au X E1, et se rapproche des formats des concurrents chaussés en 4/3.

Sous le capot, guère de surprise, on retrouve les ingrédients qui ont fait le succès des prédécesseurs du X M1. On y retrouvera entre autres le très bon capteur 16 mpixAPS C X Trans du X Pro1. Comme sur le X Pro1 en somme. et probablement avec les mêmes limitations. Dommage que Fuji n’intègre pas encore d’AF hybride à ses modèles, qui y gagneraient certainement beaucoup au change. Tout ceci placera à coup sûr le X M1 derrière les bons 4/3 de chez Olympus et Panasonic en termes de performance d’AF, comme les précédents

Representing Key Phytoplankton Groups in Ocean Carbon Cycle Models

Sponsored by: National Aeronautic Space Administration & US J.G.O.F.S.
Project Period: March 15, 1998 – March 14, 2001
Principle Investigator: Paul G. Falkowski
Co-Principle Investigator: Michael J. Behrenfeld
Co-Principle Investigator: Zbigniew S. Kolber

The primary goal of this project is to improve ocean carbon models by describing how physical and chemical forcing affects the statistical distribution of key functional phytoplankton groups. This information is critical in predicting how changes in ocean physics and chemistry will influence total and new production in future ocean model scenarios. The research is coordinated with the Ocean Carbon-cycle Modeling Intercomparison Project (OCMIP), an international project initiated in 1995 by the Global Analysis, Interpretation and Modeling (GAIM) Task Force of the International Geosphere-Biosphere Program (IGBP).
The project focuses on the development of algorithms that predict how ocean physics and chemistry affect the spatial distribution of:

  • trichodesmium sp.,the major nitrogen fixing organisms;
  • diatoms, the major group responsible for export production;
  • coccolithophores, which, as a consequence of calcification, raise pCO2; and
  • the polytaxonomic group of picoplankton, which, while they are the major carbon fixers, contribute little to carbon export.

The statistical distribution of these four functional groups will be analyzed using remotely sensed information in conjunction with sea truth data, and, based on the statistics of their distributions, “functional group profiles” will be generated. The “functional group profiles” give a probability of encountering each of the four groups in each grid cell of an OGCM. Based on these profiles, we can specify physical and chemical criteria that maximize and minimize the distributions of each group, and hence prospectively infer their distributions in climate change scenarios. From knowledge of the distributions of each group, the forcing and feedback between ocean circulation, chemistry and biological processes can be represented much more realistically in ocean general circulation/biogeochemical models.

Animated movie files: Chl_ehux_CB_anim.gif | CritIrr_ehux_cb_anim.gifMLD_ehux_CB_anim.gif| SST1_eh_cb_anim.gif

Southern Ocean Iron Experiments (SOFeX) – Collaborative Research

Sponsored by NSF – Division of Ocean Sciences
Principle Investigator: Paul G. Falkowski

This component of the Southern Ocean iron enrichment experiment is designed to provide the instrumentation and expertise for biophysical assessment of the factors limiting phytoplankton photosynthesis in the open waters of the Antarctic Ocean. Our techniques incorporate both real-time, continuous underway measurements, as well as discrete sample analysis and include: fast repetition rate (FRR) fluorometry, single-celled fast repetition rate (SCFRR) fluorometry, and low temperature fluorescence excitation/emission spectroscopy. These “tools” are capable of sensitively and reliably detecting and quantifying intrinsic biophysical limitations of phytoplankton photosynthetic processes, and provide diagnostic profiles for specific limiting factors such as iron. This program element (1) provides key data that directly tests the iron limitation hypothesis for high nutrient, low chlorophyll waters in the Southern Ocean, (2) quantifies the temporal and spatial photosynthetic responses to the iron enrichment, (3) provides the capability for real-time adaptive sampling within an enrichment area, and (4) helps to determine the taxonomic components that are iron limited, and to understand their responses to enrichment.

We propose to evaluate all of the basic variable fluorescence characteristics at sea. We will also perform post-cruise measurements.

Processes Affecting the Variability of Fluorescence Signals from Benthic Targets in Shallow Waters

Sponsored by: Office of Naval Research (ONR)

Principle Investigator:  Paul G. Falkowski

Co- Principle Investigators:  Zbigniew S. Kolber, Maxim Gorbunov

The major theme of this research project is to understand processes that contribute to fluorescence emission from benthic targets in the coastal and shallow waters with the overarching goal of developing parameterization schemes that optically detect anthropogenic objects. This effort is part of the larger Coastal Benthic Optics Program (CoBOP) DRI.

The research effort has three basic tasks:

  1. To analyze data obtained from in situ fluorescence detectors, especially the scuba-based Fast Repetition Rate Fluorometer and to iteratively improve the instrumentation and retrieval algorithms in support of CoBOP field measurements.
  2. To measure fluorescence lifetimes in the subnanosecond time domain from model organisms. This task, which will be carried out both in the field and at Rutgers University, will provide the fundamental knowledge for the interpretation of in situ lifetime measurements.
  3. To determine the molecules that give rise to the specific fluorescence signatures and to characterize their spatial and temporal distributions in relation to variations in fluorescence yields. This latter task will address the first order applicability of CoBOP optical models to subtropical and tropical shallow water benthic environments.
SCUBA-FRR Fluorometer

SCUBA-FRR Fluorometer

Natural Iron Fertilization in the Ocean and its Impact on Ocean Fixation and Carbon Cycles

Principal  Investigators:

Paul Falkowski Rutgers University falko@imcs.rutgers.edu
Michael Follows M.I.T. mick@plume.mit.edu
Yuan Gao Montclair State University gaoy@montclair.edu
Yoram Kaufman NASA kaufman@climate.gsfc.nasa.gov
Daniel Sigman Princeton University sigman@princeton.edu

Molecular Bases and Photobiological Consequences of Light Intensity Adaptation in Photosynthetic Organisms

Sponsored by: US Dept of Energy, Division of Basic Energy Bioscience
Project Period: March 1, 1999 – February 28, 2002
Principle Investigator: Paul G. Falkowski

This project addresses the basic molecular mechanisms responsible for the acclimation of the photosynthetic apparatus to changes in irradiance. We have recently identified that the redox status of the plastoquinone pool is a sensor that affects nuclear gene transcription in a eucaryotic green alga, Dunaliella tertiolecta (Escoubas et al., Proc. Nat, Acad. Sci. 92:10237-41). The research builds on that discovery by analyzing the signal transduction cascade and the cue/response functions.

The effect of redox modulation in the photosynthetic electron transport chain on the expression of a variety of nuclear genes is under investigation. The research goals are to characterize the key DNA binding factors, follow the effects of redox control on the activation of the binding factors, and examine how redox poise is related to environmental cues such as irradiance, temperature and CO2.

A working hypothesis for the molecular basis

A working hypothesis for the molecular basis
of photoacclimation in Dunaliella tertiolecta via a
chloroplastic photoreceptor, the plastoquinone pool.

The research has broad implication for understanding how environmental information is transduced to biochemical information with photosynthetic organisms, and how that information, in turn, affects nuclear gene expression.

Establishing and Improving a Traceable, Time-dependent Primary Production Algorithm for Generating NASA Standard Ocean Productivity Data Products from Satellite Measurements of Ocean Color

Sponsored by: National Aeronautics and Space Administration
Project Period: October 1, 1997 – September 30, 2000
Principle Investigators: Michael J. Behrenfeld, Paul G. Falkowski, and Zbigniew Kolber

Achieving the goals of NASA’s Mission to Planet Earth regarding the role of the oceans in global biogeochemical cycles requires both fidelity in the estimation of net phytoplankton primary production and an established mechanism for generating comparable ocean productivity data products across successive generations of ocean color sensors.
Currently, only about half of the observed variability in depth-integrated primary production (IPP) can be accounted for by any productivity model and there is no organized procedure for establishing and updating a standard algorithm for generating productivity data products. This research project comprises both fundamental studies on phytoplankton photosynthesis and working group activities which specifically address these issues.
Basic research is being conducted to improve the characterization of the maximum rate of carbon fixation within the water column (Pbopt), the estimation of which is currently the greatest source of error in productivity model estimates of IPP. The physiological model for Pbopt is based on the assembly and analysis of a variable fluorescence database. Model parameterization emphasizes process oriented relationships and is based, to the greatest extent possible, on remotely sensed physical variables.

Jan-Feb

Jan-Feb – Seasonal Global Production (in g C/m2/season) for standard parameterization of theVPG Model

Mar-Jun

Mar-Jun – – Seasonal Global Production (in g C/m2/season) for standard parameterization of theVPG Model

Jul-Sep

Jul-Sep – – Seasonal Global Production (in g C/m2/season) for standard parameterization of theVPG Model

Oct-Dec

Oct-Dec – – Seasonal Global Production (in g C/m2/season) for standard parameterization of theVPG Model

 

Our primary goal is to provide databases, algorithm structure and code, and an investigator-independent framework that permits continuity, validation, and quality assurance for primary production calculations into the 21st century.
For more information about this project, please visit our Ocean Primary Productivity Study, IMCS, Rutgers University web site.

Cryptic Protease Genes and the Triggers for Cell Death

Sponsored by NIH – General Medicine
Principle Investigator: Paul G. Falkowski

As large amounts of sequence information become available from the Human Genome Project, sequence analyses will provide clearer evidence that numerous human diseases or disorders have deep evolutionary roots. The project addresses the evolutionary origins of proteases and cell death responses as a case in point. Specifically, the research seeks to:

  • examine to the evolutionary origins of autocatalyzed cell death associated with the stress induced expression of novel (cryptic) proteases in single-celled, asexual eucaryotes, specifically the obligate photoautotrophic chlorophyte alga, Dunaliella tertiolecta,
  • elucidate the molecular triggers in physiological stress responses that lead to the induction of novel proteases and catastrophic cell death in such cells, and
  • examine to what extent the cryptic proteases are ubiquitous in eucaryotes.

These goals address the biological significance of apoptosis and autocatalyzed cell death in the context of the evolution of somatic eucaryotes and the processes that repress or silence the expression of cryptic proteases encoded within their nuclear genomes.

Profiles of proteins and proteases in main phytoplankton

In humans, protease-triggered apoptosis occurs in cytotoxic T lymphocytes and other defensive cell lines, but is also a symptom of numerous chronic diseases or disorders with little or no clear Mendalian genetic lineage. We hypothesize that the genes encoding the stress-induced proteases have been incorporated into bacterial and eukaryotic genomes from relic viral infections, comparable to the endogenous retroviral protease genes found in metazoans. These genes, normally silenced either by repressor factors or transpositions, appear to be derepressed when the organism is selectively stressed.

Biocomplexity: The Evolution and Radiation of Eucaryotic Phytoplankton Taxa

Sponsored by: National Science Foundation – Division of Ocean Sciences
Project Period: September 1, 2000 – August 31, 2005
Principle Investigators: Paul G. Falkowski, Kenneth Miller, Andrew Knoll, Oscar Schofield, Costantino Vetriani

Archived page for this project

NSF Collaborative Biocomplexity Proposal


Dr. Paul Falkowski is the Lead Investigator for the NSF Biocomplexity grant researching phytoplankton evolution. The funding for this project began September 1, 2000 and will run through August 31, 2005.

We would like to share our proposed phytoplankton evolution research to those interested in this work (i.e., Post-doctoral scientists, graduate students, etc.). Thus, we are posting our Project Summary, Project Description, and Reference information for everyone to view. Please click on the appropriate section of your choice:

We would like to acknowledge the following participants in this Biocomplexity Project:

Senior Personnel: (PIs & Co-PIs)

Name Institution Telephone number Email
Falkowski, Paul IMCS, Rutgers 732-932-6555 ext. 370 falko@imcs.rutgers.edu
Miller, Kenneth Geology, Rutgers 732-445-3622 kgm@rci.rutgers.edu
Vetriani, Costantino IMCS, Rutgers 732-932-6555 ext. 373 vetriani@imcs.rutgers.edu
Schofield, Oscar IMCS, Rutgers 732-932-6555 ext. 548 oscar@imcs.rutgers.edu
Wright, James Geology, Rutgers 732-445-5722 jdwright@rci.rutgers.edu
Reinfelder, John Env.Sci.,Rutgers 732-932-8013 reinfelder@envsci.rutgers.edu
Kent, Dennis Geology, Rutgers 732-445-2044 dvk@rci.rutgers.edu
Miller, James IMCS, Rutgers 732-932-6555 ext. 545 miller@arctic.rutgers.edu
Rosenthal, Yair IMCS, Rutgers 732-932-6555 ext. 250 rosentha@imcs.rutgers.edu
Kerkhof, Lee IMCS, Rutgers 732-932-6555 ext. 335 kerkhof@imcs.rutgers.edu
Kolber, Zbigniew IMCS, Rutgers 732-932-6555 ext. 233 zkolber@imcs.rutgers.edu
Sherrell, Robert IMCS, Rutgers 732-932-6555 ext. 252 sherrell@imcs.rutgers.edu
Iglesias, Debora IMCS, Rutgers +44-117-9287592 M.D.Iglesias-Rodriguez@bristol.ac.uk
Chen, Yibu IMCS, Rutgers 732-932-3494 yibu@imcs.rutgers.edu
Frank, Ilana IMCS, Rutgers 732-932-3497 irfrank@imcs.rutgers.edu
Bralower, Timothy U. North Carolina 919-962-0704 bralower@email.unc.edu
Armstrong, Robert SUNY – Stony Brook 631-632-3088 rarmstrong@notes.cc.sunysb.edu
Knoll, Andrew Harvard Univ. 617-495-9306 aknoll@oeb.harvard.edu
Bissett, Paul U. South Florida 813-837-3374 ext.102 paul@marine.usf.edu
Durnford, Dion U. New Brunswick 506-452-6207 durnford@unb.ca
Gersonde, Rainer Alfred Wegner Inst. rgersonde@AWI-Bremerhaven.DE
Levin, Simon Princeton U. 609-258-6880 simon@eno.Princeton.EDU
Medlin, Linda Alfred Wegner Inst. 49-471-4831-1443 lmedlin@AWI-Bremerhaven.DE
Raven, John U. Dundee +44 (0)1382 344282 p.m.marshall@dundee.ac.uk
Smetacek, Victor Alfred Wegner Inst. +49 471 4831 440 vsmetacek@AWI-Bremerhaven.DE
Taylor, Max U. British Columbia 604-822-4587 maxt@unixg.ubc.ca
Young, Jeremy Museum of Nat. His.,UK +44 (0)20 7942 5286 J.Young@nhm.ac.uk

Project Summary

The focus of this multidisciplinary research program is to understand the historical origins and environmental conditions that led to selection and radiation of the major eucaryotic phytoplankton taxa, and the ecological processes that contribute to their continued success in the contemporary ocean. The proposed research utilizes a combination of geological, molecular biological, ecological, and modeling approaches to address an important and complex puzzle in Earth system science. Our primary goal is to develop the first quantitative models of eucaryotic phytoplankton community structure in the contemporary oceans based on paleoecological and evolutionary inference. The central question raised in this proposal is: Why have three phylogenetically diverse groups of eucaryotic, unicellular algae been so ecologically successful and what does their evolutionary history tell us about the history of Earth and the ability of eucaryotic phytoplankton to accommodate to change in the future?

The proposed research seeks to test a set of three related hypotheses, from which we will develop a conceptual model for evolution and ecological success (dominance) of key phytoplankton taxa in the contemporary ocean. The central hypotheses are:

  •  The three dominant phytoplankton taxa in the contemporary ocean evolved in shallow shelf-seas in the Mesozoic Era in response to changes in the ocean environment, such as anoxia, changes in sea level, or tectonic processes that excluded ecological advantages previously afforded to chlorophytes.
  • Once established, these groups radiated rapidly. The rapid tempo of evolution was a consequence of high mutation frequencies relative to reversion and sexual recombination, resulting in high genetic potential and DNA content relative to genetic expression in the three taxa. The rapid tempo of evolution in the three taxa has permitted rapid radiation and adaptation to changing oceanic conditions throughout the Mesozoic. This rapid tempo continues to the present time.
  • The ecological dominance of the three major eucaryotic phytoplankton taxa is a consequence of pan-division traits that permit individual species within each group to rapidly accommodate large variations in oceanic conditions. These traits include the evolution of cell walls and vacuoles that respectively provide protection from predation while simultaneously optimizing the exploitation of pulsed nutrient supplies. A corollary of this hypothesis is that the structure of marine food webs in the contemporary ocean is primarily a consequence of the tempo of evolution of the three major taxa of eucaryotic phytoplankton, which itself is a consequence of continuous changes in oceanic regimes.

This ambitious research program involves 27 Senior Research Scientists from 5 US universities, and includes 6 foreign collaborators: 3 from Germany, 1 from the UK and 2 from Canada. Our approach incorporates expertise from three groups of investigators, who were selected not only for their individual expertise, but because of their proven ability to work collaboratively. The three groups contain expertise in geology and geochemistry, molecular biology and biochemistry, and algal physiology and ecological modeling. The fundamental concept is to compare paleoecological data, inferred primarily from geological and geochemical proxies, with molecular biological and biochemical information to test hypotheses 1 and 2. The paleoecological data will serve to help guide physiological experiments and ecological models to test hypotheses 1 and 3. The research program contains three basic elements: (I) A geological/geochemical team focussing on reconstructing the paleoecology at key periods in the Mesozoic; (II) A molecular biology/biochemical team engaged in elucidating how paleoecological processes have selected specific phenotypic traits that led to the origin and subsequent tempo of evolution of the major groups, and (III) An experimental ecophysiology/modeling group that quantitatively evaluates how phenotypic traits relate to the ecological success of specific taxa in the historical and contemporary ocean. These three elements will be integrated across traditional disciplinary lines and will include coordinated field, laboratory and modeling efforts. Modeling efforts will be directed towards hindcasting and forecasting the success of key phytoplankton groups using observational and experimental information.

The research program is coupled to a strong educational effort, designed to provide a broad exposure and opportunity for undergraduate and graduate students, as well as a K-12 and teacher-training program designed to integrate Earth system science in primary and secondary school curricula.

Analysis of Biophysical, Optical and Genetic Diversity of DoD Coral Reef Communities using Advanced Fluorescence and Molecular Biology Techniques

SERDP Conservation SI-1334

Sponsored by: Strategic Environmental Research and Development Program (SERDP)
Principal Investigators: Maxim Gorbunov and Paul Falkowski

Background:

The U.S. Department of Defense (DoD) maintains numerous facilities in tropical and subtropical environments that are adjacent to coral reefs.  Coral reefs are specifically susceptible to anthropogenic insult and rapidly degrade worldwide.  The development of advanced technologies for environmental monitoring of benthic communities under DoD jurisdiction requires an understanding of how different environmental factors affect the key elements of the ecosystems and the selection of specific monitoring protocols that are most appropriate for the identification and quantification of particular stresses.  Documenting the environmental state of reef communities is critical to developing remediation strategies that can both reduce anthropogenic impact and distinguish between natural stress and anthropogenic factors potentially related to military activity.  The quantitative assessment of the impact of stresses requires the accurate knowledge of baseline biophysical, optical, and genetic parameters for “healthy” coral reef communities.  Due to natural variability within populations and diversity amongst species, these parameters vary both within and between species.

The Objectives of this SERDP project are

  • to develop advanced techniques for rapid and non-destructive assessment of the viability and health of coral reef communities with the capabilities of identification and quantification of natural and anthropogenic stresses;
  • to develop prototypes of Fluorescence Induction and Relaxation (FIRe) Fluorosensors for permanent underwater monitoring stations and Remote Operated Vehicles or Diver Propulsion Vehicles;
  • to collect an extensive library of baseline data on physiological, biophysical, bio-optical and genetic diversity of coral reef communities near DoD installations.

Summary:

Rapid and non-destructive assessment of the health and viability of benthic photosynthetic organisms is based on the use of variable fluorescence technique.  This technique relies on the relationship between the efficiency of photosynthetic processes and chlorophyll fluorescence and derives a comprehensive suite of fluorescent and photosynthetic parameters of the target (Kolber et al. 1998; Gorbunov and Falkowski 2005).  In laboratory and field experiments, we study the impact of common natural stresses (elevated temperature, excess irradiance, and nutrient load), and selected anthropogenic stresses (like toxic pollutants) on the physiological status of coral.  Our results provide scientific background for the development of advanced protocols for non-destructive assessment of the health of coral reef ecosystems.  The molecular biology and genetic part of the project is focused on identification, as well as spectroscopic and genetic characterization of color proteins from corals.  This information will provide insight into the remarkable diversity of the color palette of reef corals, which is an important indicator of the health of coral reef ecosystems. The instrument development includes design and construction of advanced FIRe systems for permanent monitoring stations and autonomous vehicles.

Non-destructive assessment of the health of coral in situ by using an underwater fluorometer

Bench-top versions of the Fluorescence Induction and Relaxation (FIRe) System. (Left) – Rutgers FIRe System prototype developed in 2003-2004. (Right) – commercial FIRe Fluorometer System manufactured by Satlantic Inc. ( see www.satlantic.com/fire )

Coral cultivation facilities in Coral Laboratory at the Institute of Marine and Coastal Sciences at Rutgers

References:

  • Tchernov D, Gorbunov MY, de Vargas C, Yadav SN, Milligan AJ, Haggblom M, Falkowski PG. (2004) Membrane lipids of symbiotic algae are diagnostic of sensitivity to thermal bleaching in corals. – Proc. Nat. Acad. Sci., U.S.A., 101 (37): 13531-13535.
  • Gorbunov MY, and Falkowski PG. (2005) Fluorescence Induction and Relaxation (FIRe) Technique and Instrumentation for Monitoring Photosynthetic Processes and Primary Production in Aquatic Ecosystems. In: “Photosynthesis: Fundamental Aspects to Global Perspectives” – Proc. 13th International Congress of Photosynthesis, Montreal, Aug.29 – Sept. 3, 2004. (Eds: A. van der Est and D. Bruce), Allen Press, V.2, pp. 1029-1031.