selective preservation
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2021 ◽  
Author(s):  
Yannic C Bartsch ◽  
Xin Tong ◽  
Jaewon Kang ◽  
María J Avendaño ◽  
Eileen F Serrano ◽  
...  

Despite the dramatic spread of Omicron globally, even among highly vaccinated populations, death rates have not increased concomitantly. These data argue that alternative immune mechanisms, beyond neutralization, may continue to confer protection against severe disease. Beyond their ability to bind and block infection, antibodies contribute to control and clearance of multiple infections via their ability to direct antiviral immunity via Fc-effector mechanisms. Thus, here we probed the ability of vaccine induced antibodies, across three COVID-19 vaccines, to drive Fc-effector activity against Omicron. Despite the significant loss of IgM, IgA and IgG binding to the Omicron Receptor Binding Domain (RBD) across BNT162b2, mRNA-1273, and CoronaVac vaccines, stable isotype binding was observed across all of these vaccines to the Omicron Spike. Compromised RBD binding IgG was accompanied by a significant loss of cross RBD-specific antibody Fcγ-receptor binding by the CoronaVac vaccine, but preservation of RBD-specific FcγR2a and Fcγ3a binding across the mRNA vaccines. Conversely, Spike-specific antibodies exhibited persistent binding to Fcγ-receptors, across all three vaccines, albeit higher binding was observed with the mRNA vaccines, marked by a selective preservation of FcγR2a and Fcγ3a binding antibodies. Thus, despite the significant to near complete loss of Omicron neutralization across several vaccine platforms against Omicron, vaccine induced Spike-specific antibodies continue to recognize the virus and recruit Fc-receptors pointing to a persistent capacity for extra-neutralizing antibodies to contribute Omicron disease attenuation.


2021 ◽  
Author(s):  
◽  
Tomek Piątek

<p>Ōtaki Beach is an example of a small town by the sea romanticised by many New Zealanders, yet it suffers for not being able to grow without resorting to greenfield development and subdivision. Its coarse urban grain and wide roads prioritise cars and promote a sprawl of low-density, impermeable suburban blocks. Still, the old houses have their charm.  This thesis explores how we can grow the population of Ōtaki Beach without resorting to further greenfield development. Early design experiments centred on large multi-residential structures sited in surrounding landscapes. The final proposal though, developed in the context of adaptive reuse, focuses on exploring the potential of a single block that serves as an example.  The design experiments led to three main strategies. Firstly, unification of existing outdoor spaces generates shared landscape. Secondly, transverse pathways add permeability and refine block grain. Thirdly, selective preservation, unification and vertical stacking of existing structures constitute the formal strategy that increases density without consuming more land and gives rise to a specific architectural expression.  Final design achieves: 4-fold increase in density, taking it from 63 people/km² to over 252 people/km²; refined block grain and permeability, by growing the number of public pathways from zero to three; over 3000m² of shared landscape.</p>


2021 ◽  
Author(s):  
◽  
Tomek Piątek

<p>Ōtaki Beach is an example of a small town by the sea romanticised by many New Zealanders, yet it suffers for not being able to grow without resorting to greenfield development and subdivision. Its coarse urban grain and wide roads prioritise cars and promote a sprawl of low-density, impermeable suburban blocks. Still, the old houses have their charm.  This thesis explores how we can grow the population of Ōtaki Beach without resorting to further greenfield development. Early design experiments centred on large multi-residential structures sited in surrounding landscapes. The final proposal though, developed in the context of adaptive reuse, focuses on exploring the potential of a single block that serves as an example.  The design experiments led to three main strategies. Firstly, unification of existing outdoor spaces generates shared landscape. Secondly, transverse pathways add permeability and refine block grain. Thirdly, selective preservation, unification and vertical stacking of existing structures constitute the formal strategy that increases density without consuming more land and gives rise to a specific architectural expression.  Final design achieves: 4-fold increase in density, taking it from 63 people/km² to over 252 people/km²; refined block grain and permeability, by growing the number of public pathways from zero to three; over 3000m² of shared landscape.</p>


Geology ◽  
2021 ◽  
Author(s):  
Jacob A. Mulder ◽  
Peter A. Cawood

Most recent models of continental growth are based on large global compilations of detrital zircon ages, which preserve a distinctly episodic record of crust formation over billion-year timescales. However, it remains unclear whether this uneven distribution of zircon ages reflects a true episodicity in the generation of continental crust through time or is an artifact of the selective preservation of crust isolated in the interior of collisional orogens. We address this issue by analyzing a new global compilation of monazite ages (n &gt;100,000), which is comparable in size, temporal resolution, and spatial distribution to the zircon continental growth record and unambiguously records collisional orogenesis. We demonstrate that the global monazite and zircon age distributions are strongly correlated throughout most of Earth history, implying a link between collisional orogenesis and the preserved record of continental growth. Our findings support the interpretation that the continental crust provides a preservational, rather than generational, archive of crustal growth.


2021 ◽  
Author(s):  
Luisa Speranza ◽  
Yanis Inglebert ◽  
Claudia De Sanctis ◽  
Pei You Wu ◽  
Magdalena Kalinowska ◽  
...  

Dendritic spines, actin-rich protrusions forming the postsynaptic sites of excitatory synapses, undergo activity-dependent molecular and structural remodeling. Activation of group 1 metabotropic glutamate receptors - mGluR1 and mGluR5 - by synaptic or pharmacological stimulation, induces LTD but whether this is accompanied with spine elimination remains unresolved. A subset of telencephalic mushroom spines contains the spine apparatus (SA), an enigmatic organelle composed of stacks of smooth endoplasmic reticulum, whose formation depends on the expression of the actin-bundling protein Synaptopodin. Allocation of Synaptopodin to spines appears governed by cell-intrinsic mechanisms as the relative frequency of spines harboring Synaptopodin is conserved in vivo and in vitro. Here we show that expression of Synaptopodin/SA in spines is required for induction of mGluR-LTD at Schaffer collateral-CA1 synapses. Post-mGluR-LTD, mushroom spines lacking Synaptopodin/SA are selectively lost whereas spines harboring it are preserved, a process dependent on activation of mGluR1 but not mGluR5. Mechanistically, we find that mGluR1 supports physical retention of Synaptopodin within excitatory spine synapses during LTD while triggering lysosome-dependent degradation of the protein residing in dendritic shafts. Together, these results reveal a cellular mechanism, dependent on mGluR1, which enables selective preservation of stronger spines containing Synaptopodin/SA while eliminating weaker ones and potentially countering spurious strengthening by de novo recruitment of Synaptopodin. Overall our results identify spines with Synaptopodin/SA as the locus of mGluR-LTD and underscore the importance of the molecular microanatomy of spines in synaptic plasticity.


2021 ◽  
Author(s):  
Kirsten Hofmockel ◽  
Sheryl Bell ◽  
Chris Kasanke

&lt;p&gt;Microbial derivatives and necromass are dominant sources of soil organic matter (SOM), yet the specific microbiological and geochemical reactions leading to the persistence of microbial compounds in SOM remains to be discovered. Identification of the microbial taxa and classes of microbial-derived compounds that are selectively preserved may enhance our ability to manage SOM, particularly in agroecosystems. We examined how perennial and annual biofuel cropping systems influence the production and selective preservation of microbial residues. Our experiment was replicated on a sandy and a silty loam to test the relative importance of microbial (biotic) and mineral (abiotic) filters on necromass accumulation and persistence. Using a &lt;sup&gt;13&lt;/sup&gt;C-labeling incubation experiment, we tested the effects of cropping system and soil texture on the production and persistence of microbial-derived residues. Soils were collected from sandy loams at the Kellogg Biological Station (MI, USA) and silty loams at the Arlington Agricultural Research Station (WI, USA). These soils were amended with &lt;sup&gt;13&lt;/sup&gt;C-labeled glucose, which was rapidly incorporated into microbial biomass. After 2 months, ~50% of the added &lt;sup&gt;13&lt;/sup&gt;C remained in the bulk soil. Approximately 30% of the &lt;sup&gt;13&lt;/sup&gt;C remaining in the bulk soil was recovered in the lipid, protein, and metabolite pools. Lipids contained the most &lt;sup&gt;13&lt;/sup&gt;C (16%) and the contribution was similar in both soils. Both soils had similar protein pools, but protein from the sandy loam was significantly more enriched than protein from the silty loam. The pool of metabolites was small, but highly enriched, suggesting substantial recycling over the 2-month incubation. The majority (40%) of the whole soil &lt;sup&gt;13&lt;/sup&gt;C persisted in the SOM even after repeat extractions. The remaining ~30% of the whole soil &lt;sup&gt;13&lt;/sup&gt;C was recovered in a complex of remaining unknown debris that separates from the soil at the solvent interphase with the protein but could not be solubilized. We provide novel evidence of the carbon pools that contribute to persistent microbial residues in soil. Our results suggest that metabolites may be more important than was previously recognized. Ongoing work is identifying the labeled metabolites and characterizing the chemistry of the highly enriched protein residue fraction.&lt;/p&gt;


2021 ◽  
Author(s):  
Philippe Agard ◽  
Mark Handy

&lt;p&gt;&lt;strong&gt;The Alps preserve abundant oceanic blueschists and eclogites that exemplify the selective preservation of fragments of relatively short-lived, small, slow-spreading North Atlantic-type ocean basins (here the ~400-700 km wide Alpine Tethys), whose subducting slabs reach down to the Mantle Transition Zone. Whereas none of the subducted fragments were returned during the first half of the subduction history, those exhumed afterwards experienced conditions typical of mature subduction zones worldwide. Sedimentary-dominated units were underplated intermittently, mostly at ~30-40 km depth, while mafic/ultramafic-dominated units subducted to ~80 km (In the W. Alps), whose protoliths had formed close to the continent, were offscraped from the slab only a few Ma before continental subduction. Spatiotemporal contrasts in burial and preservation of the fragments reveal how along-strike segmentation of the continental margin affects ocean subduction dynamics.&lt;/strong&gt;&lt;/p&gt;


Elements ◽  
2021 ◽  
Vol 17 (1) ◽  
pp. 9-16
Author(s):  
Philippe Agard ◽  
Mark R. Handy

The Alps preserve abundant oceanic blueschists and eclogites that exemplify the selective preservation of fragments of relatively short-lived, small, slow-spreading North Atlantic–type ocean basins whose subducting slabs reach down to the Mantle Transition Zone at most. Whereas no subducted fragments were returned during the first half of the subduction history, those exhumed afterwards experienced conditions typical of mature subduction zones worldwide. Sedimentary-dominated units were under-plated intermittently, mostly at ~30–40 km depth. Some mafic–ultramafic-dominated units formed close to the continent were subducted to ~80 km and offscraped from the slab only a few million years before continental subduction. Spatiotemporal contrasts in burial and preservation of the fragments reveal how along-strike segmentation of the continental margin affects ocean subduction dynamics.


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