112 research outputs found
Phosphoregulation of HORMA domain protein HIM-3 promotes asymmetric synaptonemal complex disassembly in meiotic prophase in Caenorhabditis elegans
正常な精子・卵子の形成メカニズムを解明 --染色体の分離に重要なタンパク質の発見--. 京都大学プレスリリース. 2020-12-04.In the two cell divisions of meiosis, diploid genomes are reduced into complementary haploid sets through the discrete, two-step removal of chromosome cohesion, a task carried out in most eukaryotes by protecting cohesion at the centromere until the second division. In eukaryotes without defined centromeres, however, alternative strategies have been innovated. The best-understood of these is found in the nematode Caenorhabditis elegans: after the single off-center crossover divides the chromosome into two segments, or arms, several chromosome-associated proteins or post-translational modifications become specifically partitioned to either the shorter or longer arm, where they promote the correct timing of cohesion loss through as-yet unknown mechanisms. Here, we investigate the meiotic axis HORMA-domain protein HIM-3 and show that it becomes phosphorylated at its C-terminus, within the conserved “closure motif” region bound by the related HORMA-domain proteins HTP-1 and HTP-2. Binding of HTP-2 is abrogated by phosphorylation of the closure motif in in vitro assays, strongly suggesting that in vivo phosphorylation of HIM-3 likely modulates the hierarchical structure of the chromosome axis. Phosphorylation of HIM-3 only occurs on synapsed chromosomes, and similarly to other previously-described phosphorylated proteins of the synaptonemal complex, becomes restricted to the short arm after designation of crossover sites. Regulation of HIM-3 phosphorylation status is required for timely disassembly of synaptonemal complex central elements from the long arm, and is also required for proper timing of HTP-1 and HTP-2 dissociation from the short arm. Phosphorylation of HIM-3 thus plays a role in establishing the identity of short and long arms, thereby contributing to the robustness of the two-step chromosome segregation
Sub-nanosecond signal propagation in anisotropy engineered nanomagnetic logic chains
Energy efficient nanomagnetic logic (NML) computing architectures propagate
and process binary information by relying on dipolar field coupling to reorient
closely-spaced nanoscale magnets. Signal propagation in nanomagnet chains of
various sizes, shapes, and magnetic orientations has been previously
characterized by static magnetic imaging experiments with low-speed adiabatic
operation; however the mechanisms which determine the final state and their
reproducibility over millions of cycles in high-speed operation (sub-ns time
scale) have yet to be experimentally investigated. Monitoring NML operation at
its ultimate intrinsic speed reveals features undetectable by conventional
static imaging including individual nanomagnetic switching events and
systematic error nucleation during signal propagation. Here, we present a new
study of NML operation in a high speed regime at fast repetition rates. We
perform direct imaging of digital signal propagation in permalloy nanomagnet
chains with varying degrees of shape-engineered biaxial anisotropy using
full-field magnetic soft x-ray transmission microscopy after applying single
nanosecond magnetic field pulses. Further, we use time-resolved magnetic
photo-emission electron microscopy to evaluate the sub-nanosecond dipolar
coupling signal propagation dynamics in optimized chains with 100 ps time
resolution as they are cycled with nanosecond field pulses at a rate of 3 MHz.
An intrinsic switching time of 100 ps per magnet is observed. These
experiments, and accompanying macro-spin and micromagnetic simulations, reveal
the underlying physics of NML architectures repetitively operated on nanosecond
timescales and identify relevant engineering parameters to optimize performance
and reliability.Comment: Main article (22 pages, 4 figures), Supplementary info (11 pages, 5
sections
Ground deformation analysis at Campi Flegrei (Southern Italy) by CGPS and tide-gauge network
Campi Flegrei caldera is located 15 km west of the
city of Naples, within the central-southern sector of a
large graben called Campanian Plain. It is an active
volcanic area marked by a quasi-circular caldera
depression, formed by a huge ignimbritic eruption
occurred about 37000 years ago. This caldera was
generated by several collapses produced by strong
explosive eruptions (the last eruption, occurred in
1538, built an about 130 m spatter cone called Mt.
Nuovo). Campi Flegrei area periodically experiences
significant deformation episodes, with uplift
phenomena up to more than 3.5 m in 15 years (from
1970 to 1984), which caused during 1983-84 the
temporary evacuation of about 40000 people from the
ancient part of Pozzuoli town.
The deformation field obtainable by CGPS and tidegauge
stations plays an important role for the
modelling and interpretation of volcanic phenomena,
as well as for forecasting purposes.
The structural complexity of the Campi Flegrei area,
together with the evidence of a strong interaction
between magmatic chamber and shallow geothermal
system, calls for a detailed characterization of the
substructure and of magma-water interaction
processes.
The incoming experiment of deep drilling, down to
about 4 km, will give detailed structural and physical
constraints able to resolve the intrinsic ambiguities of
geophysical data and in particular geodetic ones.
In this poster we describe the recent ground
deformations at Campi Flegrei area by means of GPS
technique and tide gauge stations, discussing the
possible interpretations also in light of further
constraints likely coming from the next CFDDP
(Campi Flegrei Deep Drilling) deep drilling experiment
SNX17 protects integrins from degradation by sorting between lysosomal and recycling pathways.
The FERM-like domain-containing sorting nexins of the SNX17/SNX27/SNX31 family have been proposed to mediate retrieval of transmembrane proteins from the lysosomal pathway. In this paper, we describe a stable isotope labeling with amino acids in culture-based quantitative proteomic approach that allows an unbiased, global identification of transmembrane cargoes that are rescued from lysosomal degradation by SNX17. This screen revealed that several integrins required SNX17 for their stability, as depletion of SNX17 led to a loss of β1 and β5 integrins and associated a subunits from HeLa cells as a result of increased lysosomal degradation. SNX17 bound to the membrane distal NPXY motif in β integrin cytoplasmic tails, thereby preventing lysosomal degradation of β integrins and their associated a subunits. Furthermore, SNX17-dependent retrieval of integrins did not depend on the retromer complex. Consistent with an effect on integrin recycling, depletion of SNX17 also caused alterations in cell migration. Our data provide mechanistic insight into the retrieval of internalized integrins from the lysosomal degradation pathway, a prerequisite for subsequent recycling of these matrix receptors
“Dogged” Search of Fresh Nakhla Surfaces Reveals New Alteration Textures
Special Issue: 74th Annual Meeting of the Meteoritical Society, August 8-12, 2011, London, U.K.International audienceCarbonaceous chondrites are considered as amongst the most primitive Solar System samples available. One of their primitive characteristics is their enrichment in volatile elements.This includes hydrogen, which is present in hydrated and hydroxylated minerals. More precisely, the mineralogy is expected to be dominated by phyllosilicates in the case of CM chondrites, and by Montmorillonite type clays in the case of CI. Here, in order to characterize and quantify the abundance of lowtemperature minerals in carbonaceous chondrites, we performed thermogravimetric analysis of matrix fragments of Tagish Lake, Murchison and Orgueil
Crop Updates 2000 - Lupins
This session covers nineteen papers from different authors:
1.1999 Lupin Highlights, Bill O’Neill, LUPIN PRODUCTIVITY IMPROVEMENTS AND INDUSTRY DEVELOPMENT
LUPIN ANTHRACNOSE
2. Anthracnose – 1999/2000, Geoff Thomas and Mark Sweetingham, Agriculture Western Australia
LUPIN BREEDING AND AGRONOMY
3. The genetic control of mildly restricted branching in narrow-leafed lupin (Lupinus augustifolius L), Kedar Adhikari1,3, Nick Galwey1,3 and Miles Dracup2,3 1Plant Sciences, University of Western Australia 2Agriculture Western Australia 3Cooperative Research Centre for Legumes in Mediterranean Agriculture, University of Western Australia
4. Genotype x time of sowing interaction in lupins – Mingenew, Bob French, Agriculture Western Australia
5. Genotype x time of sowing interaction in lupins – Wongan Hills, Bob French, Agriculture Western Australia
6. Genetic variation in lupin tolerance to Brown Leaf Spot, Bob French, Agriculture Western Australia
7. Yellow lupin management in Western Australia, Bob French, Agriculture Western Australia
APHIDS AND VIRUS CONTROL
8. Forecasting aphid and virus risk in lupins, Debbie Thackray, Jenny Hawkes and Roger Jones, Centre for Legumes in Mediterranean Agriculture and Agriculture Western Australia
9. When should lupin crops be sprayed for aphids to achieve maximum yield response? Françoise Berlandier, Agriculture Western Australia
10. Yield limiting potential of the new, non-necrotic strain of bean yellow mosaic virus in narrow-leafed lupin, Roger Jones, Yvonne Cheng and Lisa Smith, Crop Improvement Institute, Agriculture Western Australia, and Centre for Legumes in Mediterranean Agriculture
LUPIN NUTRITION
11. Increasing the value of a rotation by applying lime, Chris Gazey and Michael O’Connell, Agriculture Western Australia
HERBICIDE TOLERANCE AND WEED CONTROL
12. Herbicide damage does not mean lower yield in Lupins, Peter Carlton, Trials Coordinator, Elders Limited
13. Effect of herbicides Tordonä 75D and Lontrelä, used for eradication of Skeleton Weed, on production of Lupins in following seasons, John R. Peirce and Brad J. Rayner, Agriculture Western Australia
14. Herbicide tolerance of lupins, Terry Piper, Agriculture Western Australia
15. Tanjil lupins will tolerate metribuzin under the right conditions, Peter Newman, Agronomist Elders Limited and Cameron Weeks, Mingenew/Irwin Group
LUPIN ESTABLISHMENT
16. A new seed pressing system for ryegrass suppression and healthy lupin establishment, Mohammad Amjad and Glen Riethmuller,Agriculture Western Australia
17. Banded surfactant for better lupin yield on non-wetting sand, Dr Paul Blackwell, Agriculture Western Australia
DROUGHT TOLERANCE
18. Drought tolerance of lupin genotypes in Western Australia, Jairo A. Palta1,2,, Neil C. Turner1,2, Robert J. French2,3 ,1CSIRO Plant Industry, Centre for Mediterranean Agricultural Research, 2Centre for Legumes in Mediterranean Agriculture, University of Western Australia, 3Agriculture Western Australia,
19. Stem carbohydrate in lupins: a possible buffer to maintain seed growth under adverse conditions, Bob French1, Tim Setter2, Jairo Palta3 , 1Agriculture Western Australia, and CLIMA, 2Agriculture Western Australia, 3CSIRO, Floreat Park, and CLIM
Clinical Research and Development of Tuberculosis Diagnostics: Moving From Silos to Synergy
The development, evaluation, and implementation of new and improved diagnostics have been identified as critical needs by human immunodeficiency virus (HIV) and tuberculosis researchers and clinicians alike. These needs exist in international and domestic settings and in adult and pediatric populations. Experts in tuberculosis and HIV care, researchers, healthcare providers, public health experts, and industry representatives, as well as representatives of pertinent US federal agencies (Centers for Disease Control and Prevention, Food and Drug Administration, National Institutes of Health, United States Agency for International Development) assembled at a workshop proposed by the Diagnostics Working Group of the Federal Tuberculosis Taskforce to review the state of tuberculosis diagnostics development in adult and pediatric populations
Constraining the Origin of Impact Craters on Al Foils from the Stardust Interstellar Dust Collector
Preliminary examination (PE) of the aerogel tiles and Al foils from the Stardust Interstellar Dust Collector has revealed multiple impact features. Some are most likely due to primary impacts of interstellar dust (ISD) grains, and others are associated with secondary impacts of spacecraft debris, and possibly primary impacts of interplanetary dust particles (IDPs) [1, 2]. The current focus of the PE effort is on constraining the origin of the individual impact features so that definitive results from the first direct laboratory analysis of contemporary ISD can be reported. Because crater morphology depends on impacting particle shape and composition, in addition to the angle and direction of impact, unique particle trajectories are not easily determined. However, elemental analysis of the crater residues can distinguish real cosmic dust from the spacecraft debris, due to the low cosmic abundance of many of the elements in the spacecraft materials. We present here results from the elemental analysis of 24 craters and discuss the possible origins of 4 that are identified as candidate ISD impact
Final Reports of the Stardust ISPE: Seven Probable Interstellar Dust Particles
The Stardust spacecraft carried the first spaceborne collector specifically designed to capture and return a sample of contemporary interstellar dust to terrestrial laboratories for analysis [1]. The collector was exposed to the interstellar dust stream in two periods in 2000 and 2002 with a total exposure of approximately 1.8 10(exp 6) square meters sec. Approximately 85% of the collector consisted of aerogel, and the remainder consisted of Al foils. The Stardust Interstellar Preliminary Examination (ISPE) was a consortiumbased effort to characterize the collection in sufficient detail to enable future investigators to make informed sample requests. Among the questions to be answered were these: How many impacts are consistent in their characteristics with interstellar dust, with interplanetary dust, and with secondary ejecta from impacts on the spacecraft? Are the materials amorphous or crystalline? Are organics detectable? An additional goal of the ISPE was to develop or refine the techniques for preparation, analysis, and curation of these tiny samples, expected to be approximately 1 picogram or smaller, roughly three orders of magnitude smaller in mass than the samples in other small particle collections in NASA's collections - the cometary samples returned by Stardust, and the collection of Interplanetary Dust Particles collected in the stratosphere
The social dimension of globalization: A review of the literature
With globalization affecting so many inter-connected areas, it is difficult to grasp its full impact. This literature review of over 120 sources considers the impact of globalization on wages and taxes, poverty, inequality, insecurity, child labour, gender, and migration. Opening with some stylized facts concerning globalization in 1985-2002, the authors then highlight recent findings on these areas, reporting on controversies and on emerging consensus where it exists. There follows a review of national and international policy responses designed to make globalization more sustainable and equitable and to deliver decent jobs, security and a voice in decision-making
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