647 research outputs found
Cassini ISS astrometry of the Saturnian satellites: Tethys, Dione, Rhea, Iapetus, and Phoebe 2004-2012
This work was mainly funded by European Communityâs
Seventh Framework Program (FP7/2007-2013) under grant agreement 263466
for the FP7-ESPaCE, and partially by UPMC-EMERGENCE (contract number
EME0911), for which R.T. and V.L. are grateful. R.T. was also supported
by the Cassini mission. In addition, this work was supported by the Science
and Technology Facilites Council (Grant No. ST/F007566/1) and C.D.M. and
N.J.C. are grateful to them for financial assistance. C.D.M. is also grateful to
the Leverhulme Trust for the award of a Research Fellowship
Chemical and microbial leaching of valuable metals from PCBs and tantalum capacitors of spent mobile phones
We compared chemical and microbial leaching for multi-metal extraction from printed circuit boards (PCBs) and tantalum capacitor scrap. A mixed consortium of acidophiles and heterotrophic fungal strains were used in the experiments and compared to chemical leaching using specific acids (sulfuric, citric and oxalic acids). Under optimum conditions, 100% extraction efficiency of Cu, and nearly 85% of Zn, Fe, Al and Ni were achieved from PCB and tantalum capacitor scrap samples using sulfuric acid. The mixed consortium of acidophiles successfully mobilized, Ni and Cu (99% and 96%, respectively) while Fe, Zn, Al and Mn reached an extraction yield of 89, 77, 70 and 43%, respectively, from the PCB samples. For the tantalum capacitor samples, acidophiles mobilized 92% Cu, 88% Ni, 78% Fe, 77% Al, 70% Zn and 57% Mn. Metal mobilization from PCBs and tantalum capacitor scrap by A. niger filtrate showed efficient solubilization of Cu, Fe, Al, Mn, Ni, Pb and Zn at an efficiency of 52, 29, 75, 5, 61, 21 and 35% from PCB samples and 61, 25, 69, 23, 68, 15 and 45% from tantalum capacitor samples, respectively. Microbial leaching proved viable as a method to extract base metals but was less specific for tantalum and precious metals in electronic waste. The implications of these results for further processing of waste electronic and electrical equipment (WEEE) are considered in potential hybrid treatment strategies
PRO3DÂź: A Tool for High Resolution Rendering and Geological Aanalyses of Martian Rover-Derived Digital Outcrop Models
Photometry using the Infrared Array Camera on the Spitzer Space Telescope
We present several corrections for point source photometry to be applied to
data from the Infrared Array Camera (IRAC) on the Spitzer Space Telescope.
These corrections are necessary because of characteristics of the IRAC arrays
and optics and the way the instrument is calibrated in-flight. When these
corrections are applied, it is possible to achieve a ~2% relative photometric
accuracy for sources of adequate signal to noise in an IRAC image.Comment: 16 pages, 13 figures. Accepted for publication in the Publications of
the Astronomical Society of the Pacifi
Standardized Diagnostics Including PET-CT Imaging, Bilateral Tonsillectomy and Neck Dissection Followed by Risk-Adapted Post-Operative Treatment Favoring Radio-Chemotherapy Improve Survival of Neck Squamous Cell Carcinoma of Unknown Primary Patients
Background: About five to 10% of cancers in the head and neck region are neck
squamous cell carcinoma of unknown primary (NSCCUP). Their diagnosis and treatment
are challenging given the risk of missing occult tumors and potential relapse. Recently, we
described human papillomavirus (HPV)-related NSCCUP-patients (NSCCUP-P) as a
subgroup with superior survival. However, standardized diagnostic workup, novel
diagnostic procedures, decision-making in the multidisciplinary tumor board (MDTB)
and multimodal therapy including surgery and post-operative radio-chemotherapy
(PORCT) may also improve survival.
Methods: For assessing the impact of standardized diagnostic processes simultaneously
established with the MDTB on outcome, we split our sample of 115 NSCCUP-P into two
cohorts treated with curative intent from 1988 to 2006 (cohort 1; n = 53) and 2007 to 2018
(cohort 2; n = 62). We compared diagnostic processes and utilized treatment modalities
applying Chi-square tests, and outcome by KaplanâMeier plots and Cox regression.
Results: In cohort 2, the standardized processes (regular use of [18F]-FDG-PET-CT
imaging followed by examination under anesthesia, EUA, bilateral tonsillectomy and neck
dissection, ND, at least of the affected site) improved detection of primaries (P = 0.026)
mostly located in the oropharynx (P = 0.001). From 66.0 to 87.1% increased ND
frequency (P = 0.007) increased the detection of extracapsular extension of neck
nodes (ECE+) forcing risk factor-adapted treatment by increased utilization of cisplatin-based PORCT that improved 5-years progression-free and overall survival from 60.4 and
45.3 to 67.7% (P = 0.411) and 66.1% (P = 0.025).
Conclusions: Standardized diagnostic workup followed by ND and risk-factor adapted
therapy improves survival of NSCCUP-P
Standardized Diagnostic Workup and Patient-Centered Decision Making for Surgery and Neck Dissection Followed by Risk-Factor Adapted Adjuvant Therapy Improve Loco-Regional Control in Local Advanced Oral Squamous Cell Carcinoma
Background: Standardized staging procedures and presentation of oral squamous cell
carcinoma (OSCC) patients in multidisciplinary tumor boards (MDTB) before treatment
and utilization of elective neck dissection (ND) are expected to improve the outcome,
especially in local advanced LAOSCC (UICC stages IIIâIVB). As standardized diagnostics
but also increased heterogeneity in treatment applied so far have not been demonstrated
to improve outcome in LAOSCC, a retrospective study was initiated.
Methods: As MDTB was introduced into clinical routine in 2007, 316 LAOSCC patients
treated during 1991-2017 in our hospital were stratified into cohort 1 treated before
(n=104) and cohort 2 since 2007 (n=212). Clinical characteristics, diagnostic procedures
and treatment modality of patients were compared using Chi-square tests and outcome
analyzed applying Kaplan-Meier plots and log-rank tests as well as Cox proportional
hazard regression. Propensity scores (PS) were used to elucidate predictors for impaired
distant metastasis-free survival (DMFS) in PS-matched patients.
Results: Most patient characteristics and treatment modalities applied showed
insignificant alteration. Surgical treatment included significantly more often resection of
the primary tumor plus neck dissection, tracheostomy and percutaneous endoscopic
gastrostomy tube use. Cisplatin-based chemo-radiotherapy was the most frequent. Only
insignificant improved disease- (DFS), progression- (PFS) and event-free (EFS) as well as
tumor-specific (TSS) and overall survival (OS) were found after 2006 as local (LC) and locoregional
control (LRC) were significantly improved but DMFS significantly impaired.
Cox regression applied to PS-matched patients elucidated N3, belonging to cohort 2 and
cisplatin-based chemo-radiotherapy as independent predictors for shortened DMFS. The
along chemo-radiotherapy increased dexamethasone use in cohort 2 correlates with
increased DM.
Conclusions: Despite standardized diagnostic procedures, decision-making considering
clear indications and improved therapy algorithms leading to improved LC and LRC,
shortened DMFS hypothetically linked to increased dexamethasone use had a detrimental
effect on TSS and OS
High-Throughput Genome-Wide Genotyping To Optimize the Use of Natural Genetic Resources in the Grassland Species Perennial Ryegrass (Lolium perenne L.)
The natural genetic diversity of agricultural species is an essential genetic resource for breeding programs aiming to improve their ecosystem and production services. A large natural ecotype diversity is usually available for most grassland species. This could be used to recombine natural climatic adaptations and agronomic value to create improved populations of grassland species adapted to future regional climates. However describing natural genetic resources can be long and costly. Molecular markers may provide useful information to help this task. This opportunity was investigated for Lolium perenne L., using a set of 385 accessions from the natural diversity of this species collected right across Europe and provided by genebanks of several countries. For each of these populations, genotyping provided the allele frequencies of 189,781 SNP markers. GWAS were implemented for over 30 agronomic and/or putatively adaptive traits recorded in three climatically contrasted locations (France, Belgium, Germany). Significant associations were detected for hundreds of markers despite a strong confounding effect of the genetic background; most of them pertained to phenology traits. It is likely that genetic variability in these traits has had an important contribution to environmental adaptation and ecotype differentiation. Genomic prediction models calibrated using natural diversity were found to be highly effective to describe natural populations for almost all traits as well as commercial synthetic populations for some important traits such as disease resistance, spring growth or phenological traits. These results will certainly be valuable information to help the use of natural genetic resources of other species
Canonical correlations reveal adaptive loci and phenotypic responses to climate in perennial ryegrass
Germplasm from perennial ryegrass (Lolium perenne L.) natural populations is useful for breeding because of its adaptation to a wide range of climates. Climateâadaptive genes can be detected from associations between genotype, phenotype and climate but an integrated framework for the analysis of these three sources of information is lacking. We used two approaches to identify adaptive loci in perennial ryegrass and their effect on phenotypic traits. First, we combined GenomeâEnvironment Association (GEA) and GWAS analyses. Then, we implemented a new test based on a Canonical Correlation Analysis (CANCOR) to detect adaptive loci. Furthermore, we improved the previous perennial ryegrass gene set by de novo gene prediction and functional annotation of 39,967 genes. GEAâGWAS revealed eight outlier loci associated with both environmental variables and phenotypic traits. CANCOR retrieved 633 outlier loci associated with two climatic gradients, characterized by coldâdry winter versus mildâwet winter and long rainy season versus long summer, and pointed out traits putatively conferring adaptation at the extremes of these gradients. Our CANCOR test also revealed the presence of both polygenic and oligogenic climatic adaptations. Our gene annotation revealed that 374 of the CANCOR outlier loci were positioned within or close to a gene. Coâassociation networks of outlier loci revealed a potential utility of CANCOR for investigating the interaction of genes involved in polygenic adaptations. The CANCOR test provides an integrated framework to analyse adaptive genomic diversity and phenotypic responses to environmental selection pressures that could be used to facilitate the adaptation of plant species to climate change
Pleistocene climate changes, and not agricultural spread, accounts for range expansion and admixture in the dominant grassland species <i>Lolium perenne</i> L.
International audienceAim: Grasslands have been pivotal in the development of herbivore breeding since the Neolithic and still represent the most widespread agricultural land use across Europe. However, it remains unclear whether the current largeâscale genetic variation of plant species found in natural grasslands of Europe is the result of human activities or natural processes. Location: Europe. Taxon: Lolium perenne L. (perennial ryegrass). Methods: We reconstructed the phylogeographic history of L. perenne, a dominant grassland species, using 481 natural populations, including 11 populations of closely related taxa. We combined GenotypingâbyâSequencing (GBS) and poolâSequencing (poolâSeq) to obtain highâquality allele frequency calls of ~500 k SNP loci. We performed genetic structure analyses and demographic reconstructions based on the site frequency spectrum (SFS). We additionally used the same genotyping protocol to assess the genomic diversity of a set of 32 cultivars representative of the L. perenne cultivars widely used for forage purposes. Results: Expansion across Europe took place during the WĂŒrm glaciation (12â110 kya), a cooling period that decreased the dominance of trees in favour of grasses. Splits and admixtures in L. perenne fit historical climate changes in the Mediterranean basin. The development of agriculture in Europe (7â3.5 kya), that caused an increase in the abundance of grasslands, did not have an effect on the demographic patterns of L. perenne. We found that most modern cultivars are closely related to natural diversity from north-western Europe. Thus, modern cultivars do not represent the wide genetic variation found in natural populations. Main conclusions: Demographic events in L. perenne can be explained by the changing climatic conditions during the Pleistocene. Natural populations maintain a wide genomic variability at continental scale that has been minimally exploited by recent breeding activities. This variability constitutes valuable standing genetic variation for future adaptation of grasslands to climate change, safeguarding the agricultural services they provide
Species richness in dry grassland patches of eastern Austria: A multi-taxon study on the role of local, landscape and habitat quality variables
AbstractAccording to island biogeography theory, the species richness of patches is determined by their size and spatial isolation, while in conservation practice, it is patch quality that determines protection and guides management. We analysed whether size, isolation or habitat quality are most important for the species richness in a set of 50 dry grassland fragments in agricultural landscapes of eastern Austria. We studied two plant taxa (vascular plants, bryophytes) and 11 invertebrate taxa (gastropods, spiders, springtails, grasshoppers, true bugs, leafhoppers and planthoppers, ground beetles, rove beetles, butterflies and burnets, ants and wild bees). The species richness of three categories was analysed: (1) dry grassland specialist species, (2) all grassland species and (3) all species. We used regression and hierarchical partitioning techniques to determine the relationship between species richness and environmental variables describing patch size and shape, patch quality, landscape configuration and landscape quality. The area-isolation paradigm was only applicable for dry grassland specialists, which comprised 12% of all species. Richness of all grassland species was determined mostly by landscape heterogeneity parameters. Total species richness was highly influenced by spillover from adjacent biotopes, and was significantly determined by the percentage of arable land bordering the patches. When analysing all taxa together, species richness of dry grassland specialists was significantly related to historical patch size but not to current patch size, indicating an extinction debt. At the landscape scale, the variable âshort-grass areaâ was a better predictor than the less specific variable âarea of extensively used landscape elementsâ. âDistance to mainlandâ was a good predictor for specialists of mobile animal taxa. Plant specialists showed a pronounced dependence on quality measures at the patch scale and at the landscape scale, whereas animal specialists were influenced by patch size, patch quality, landscape quality and isolation measures. None of the taxa benefited from linear structures in the surroundings. In conclusion, high patch quality and a network of high-quality areas in the surrounding landscape should be the best conservation strategy to ensure conservation of dry grassland specialists. This goal does not conflict with the specific demands of single taxa
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