Biotic response of plankton communities to Middle to Late Miocene monsoon wind and nutrient flux changes in the Oman margin upwelling zone

Understanding past dynamics of upwelling cells is an important aspect of assessing potential upwelling changes in future climate change scenarios. Our present understanding of nutrient fluxes throughout the world's oceans emphasizes the importance of intermediate waters transporting nutrients from the Antarctic divergence into the middle and lower latitudes. These nutrient-rich waters fuel productivity within wind-driven upwelling cells in all major oceans. One such upwelling system is located along the Oman margin in the western Arabian Sea (WAS). Driven by cross-hemispheric winds, the WAS upwelling zone's intense productivity led to the formation of one of the most extensive oxygen minimum zones known today. In this study covering the Middle to Late Miocene at Ocean Drilling Program (ODP) Site 722, we investigate the inception of upwelling-derived primary productivity. This study presents new plankton assemblage data in the context of existing model- and data-based evidence constraining the tectonic and atmospheric boundary conditions for upwelling in the WAS. With this research, we build upon the original planktonic foraminifer-based research by Dick Kroon in 1991 as part of his research based on the ODP LEG 117. We show that monsoonal winds likely sustained upwelling since the emergence of the Arabian Peninsula after the Miocene Climatic Optimum (MCO) ∼ 14.7 Ma, with fully monsoonal conditions occurring since the end of the Middle Miocene Climatic Transition (MMCT) at ∼ 13 Ma. However, changing nutrient fluxes through Antarctic Intermediate and sub-Antarctic Mode Waters (AAIW/SAMW) were only established after ∼ 12 Ma. Rare occurrences of diatom frustules correspond to the maximum abundances of Reticulofenestra haqii and Reticulofenestra antarctica, indicating higher upwelling-derived nutrient levels. By 11 Ma, diatom abundance increases significantly, leading to alternating diatom blooms and high-nutrient-adapted nannoplankton taxa. These changes in primary producers are also well reflected in geochemical proxies with increasing δ15Norg. values (&gt; 6 ‰) and high organic carbon accumulation. These proxies provide further independent evidence for high productivity and the onset of denitrification simultaneously. Our multi-proxy-based evaluation of Site 722 primary producers provides evidence for a stepwise evolution of Middle to Late Miocene productivity in the western Arabian Sea for the first time. The absence of a clear correlation with existing deep marine climate records suggests that both local wind patterns and intermediate water nutrient changes likely modulated productivity in the western Arabian Sea during the Middle to Late Miocene. Finally, we show that using a multi-proxy record provides novel insights into how plankton responded to changing nutrient conditions through time in a monsoon-wind-driven upwelling zone.</p

The tomato cis– prenyltransferase gene family

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/1/tpj12063-sup-0004-FigureS4.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/2/tpj12063-sup-0005-FigureS5.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/3/tpj12063-sup-0002-FigureS2.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/4/tpj12063-sup-0003-FigureS3.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/5/tpj12063-sup-0001-FigureS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/6/tpj12063.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/96709/7/tpj12063-sup-0006-TableS1.pd

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI)is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG)are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD)in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI)is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR)hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP)and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen)has not been established. Regenerative medicine approaches (eg, cell, gene therapies)for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative. © 2019 Society for Vascular Surgery and European Society for Vascular Surger

Enzyme‐Cleavable Linkers for Protein Chemical Synthesis through Solid‐Phase Ligations

International audienceThe total synthesis of long proteins requires the assembly of multiple fragments through successive ligations. The need for intermediate purification steps is a strong limitation, particularly in terms of overall yield. One solution to this problem would be solid-supported chemical ligation (SPCL), for which a first peptide segment must be immobilized on a SPCL-compatible solid support through a linker that can be cleaved under very mild conditions to release the assembled protein. The cleavage of SPCL linkers has previously required chemical conditions sometimes incompatible with sensitive protein targets. Herein, we describe an alternative enzymatic approach to trigger cleavage under extremely mild and selective conditions. Optimization of the linker structure and use of a small enzyme able to diffuse into the solid support were key to the success of the strategy. We demonstrated its utility by the assembly of three peptide segments on the basis of native chemical ligation to afford a 15 kDa polypeptide

Quantitative nannofossil assemblage and planktonic foraminifer data for ODP Site 117-722B

This dataset contains nannofossil assemblage and planktonic foraminifera assemblage data, the total encountered abundance of diatoms from ODP Site 722B. D/V JOIDES Resolution carried out drilling of ODP Site 722 as part of ODP Leg 117 between the 6th and 8th of September 1989. The samples used for data analysis presented in this entry were sampled from drill cores cored by XCB (see Shipboard Scientific Party, 1989; doi:10.2973/odp.proc.ir.117.107.1989). Sampling was conducted in the Kochi Core Center (KCC) in 2018. The data in this submission was generated to conduct research into upwelling and nutrient flux changes in the Oman Margin Upwelling Zone, details on data acquisition and hypothesis can be found in the associated publication. Nannofossil data was generated at JAMSTEC, Yokosuka, Japan, in April 2019 on an Olympus X52 polarizing light microscope under 1000x magnification. Calculation of total abundances of nannofossil and diatom and the sum of all siliceous fragments (including diatoms, radiolarian fragments and silicoflagellates) are given as numbers per gram (#/g) of dry bulk sediment following the methodology of Bordiga et al. (2015; doi:10.1016/j.revmic.2015.05.002). The dataset further provides sample-specific bulk accumulation rates based on the interpolated bulk density data based on shipboard moisture and density (MAD) data present in the ODP Site 722 Site Report of ODP Leg 117 (Shipboard Scientific Party, 1989; doi:10.2973/odp.proc.ir.117.107.1989), allowing for calculating calcareous nannofossil, diatom and planktonic foraminifer fluxes. Planktonic foraminifera assemblage data was generated at the University of Graz using a Zeiss V8 stereo microscope in 2019. Samples were sieved using a standard sieve set and picked from the size factions <500 µm, 500 - 250 µm and 250 - 125 µm. Foraminifer assemblage data is provided as specimens per g of sediment (#/g) and percentage data (%). The percentage data of foraminifera assemblages also contains information on the habitat of the identified planktonic foraminifera taxa to reproduce the ecological grouping of the taxa as applied in Auer et al. (pre-print 2023; doi:10.5194/cp-2023-14). The age model of all provided datasets is based on Bialik et al. (2020; doi:10.1029/2019pa003762)

Quantitative nannofossil assemblage and planktonic foraminifer data for ODP Hole 117-722B

We present nannofossil assemblage and planktonic foraminifera assemblage data from ODP Site 722B (16.6218°N/59.7953°E). D/V JOIDES Resolution carried out original drilling as part of ODP leg 117 between the 6th and 8th of September 1987. The samples included in this entry were all cored originally by XCB. Sampling was carried out in the Kochi core repository in 2018. Nannofossil data (generated at JAMSTEC, Yokosuka, Japan; in April 2019) has been corrected to reflect total nannofossil abundances per g/carboante to correct for the occurrences of high diatom fluxes in the Late Miocene. Planktonic foraminifera assemblage data was generated in August 2019 as part of an MSc thesis at the Institute of Earth Sciences, University of Graz, Austria

Synthesis of aryl-thioglycopeptides through chemoselective Pd-Mediated conjugation

International audienceWe describe herein a Pd-catalyzed methodology for the thioglycoconjugation of iodoaryl peptides and aminoacids. This operationally simple process occurs under semi-aqueous conditions and displays wide substrate scope. The strategy has been successfully applied to both the thioglycosylation of unprotected peptides and the generation of thioglyco-aminoacid building blocks, including those suitable for solid phase peptide synthesis. To demonstrate the broad potential of this technique for late stage functionalization, we successfully incorporated challenging unprotected β-S-GlcNAc- and α-S-GalNAc- derivatives into very long unprotected peptides. This study opens the way to new applications in chemical biology, considering the well-recognized advantages of S-glycosides over O-glycosides in terms of resistance towards both enzymatic and chemical degradation