1. OTU-based identification of bacterial symbionts from weevil gut microbiomes failed to identify the known symbiont "Candidatus Nardonella", which was highly divergent in the database.
2. Phylogenetic placement of sequences identified over 30% of reads as "Candidatus Nardonella" and revealed its presence in previously unstudied weevil subfamilies.
3. Analysis of short 16S NGS sequences was still useful for phylogenetic and coevolutionary analyses of "Candidatus Nardonella" and localized patterns of coevolution between weevil hosts and their symbionts were recovered.
Genome-wide association study (GWAS) technology has been a primary method for identifying the genes responsible for diseases and other traits for the past ten years. GWAS continues to be highly relevant as a scientific method. Over 2,000 human GWAS reports now appear in scientific journals. Our free eBook aims to explain the basic steps and concepts to complete a GWAS experiment.
GWAS of Resistance to Stem and Sheath Diseases of Uruguayan Advanced Rice Bre...CIAT
Speaker: Lic. JUAN ROSAS, (MSc.) Programa de Arroz INIA-Uruguay y estudiante de Doctorado en Ciencias Agrarias de la Universidad de la República de Uruguay
Presentation from the ECDC expert consultation on Whole Genome Sequencing organised by the European Centre of Disease Prevention and Control - Stockholm, 19 November 2015
Potential for genomic selection in indigenous cattle breeds and results of GWAS in Gir dairy cattle of Gujrat by Dr.Pravin Kandhani and Dr. Vijay Trivedi KAMDHENU UNIVERSITY GANDHINAGAR
Genome-wide association study (GWAS) technology has been a primary method for identifying the genes responsible for diseases and other traits for the past ten years. GWAS continues to be highly relevant as a scientific method. Over 2,000 human GWAS reports now appear in scientific journals. Our free eBook aims to explain the basic steps and concepts to complete a GWAS experiment.
GWAS of Resistance to Stem and Sheath Diseases of Uruguayan Advanced Rice Bre...CIAT
Speaker: Lic. JUAN ROSAS, (MSc.) Programa de Arroz INIA-Uruguay y estudiante de Doctorado en Ciencias Agrarias de la Universidad de la República de Uruguay
Presentation from the ECDC expert consultation on Whole Genome Sequencing organised by the European Centre of Disease Prevention and Control - Stockholm, 19 November 2015
Potential for genomic selection in indigenous cattle breeds and results of GWAS in Gir dairy cattle of Gujrat by Dr.Pravin Kandhani and Dr. Vijay Trivedi KAMDHENU UNIVERSITY GANDHINAGAR
Association mapping approaches for tagging quality traits in maizeSenthil Natesan
Association mapping has been widely used to study the genetic basis of complex traits in human and animal systems and is a very efficient and effective method for confirming candidate genes or for identifying new genes (Altshuler et al., 2008). Association mapping is now being increasingly used in a wide range of plants (Rafalski, 2010), where it appears to be more powerful than in humans or animals (Zhu et al., 2008). Unlike linkage mapping, association mapping can explore all the recombination events and mutations in a given population and with a higher resolution (Yu and Buckler, 2006). However, association mapping has a lower power to detect rare alleles in a population, even those with large effects, than linkage mapping (Hill et al., 2008). Yan et al., (2010) demonstrated that the gene encoding β-carotene hydroxylase 1 (crtRB1) underlies a principal quantitative trait locus associated with β-carotene concentration and conversion in maize kernels has been identified through candidate gene strategy of association mapping.
MAGIC :Multiparent advanced generation intercross and QTL discovery Senthil Natesan
MAGIC or multiparent advanced generation inter-crosses is an experimental method that increases the precision with which genetic markers are linked to quantitative trait loci (QTL). This method was first introduced by (Mott et al., 2000) in animals as an extension of the advanced intercrossing (AIC) approach suggested by (Darvasi and Soller , 1995)for fine mapping multiple QTLs for multiple traits. Advanced Intercrossed Lines (AILs) are generated by randomly and sequentially intercrossing a population initially originating from a cross between two inbred lines.
MAGIC involves multiple parents, called founder lines, rather than bi-parental control. AILs increase the recombination events in small chromosomal regions for the purpose of fine mapping. These lines are then cycled through multiple generations of outcrossing. Each generation of random mating reduces the extent of linkage disequilibrium (LD), allowing the QTL to be mapped more accurately.
Presentation delivered by Dr. Jesse Poland (Kansas State University, USA) at Borlaug Summit on Wheat for Food Security. March 25 - 28, 2014, Ciudad Obregon, Mexico.
http://www.borlaug100.org
Research Program Genetic Gains (RPGG) Review Meeting 2021: From Discovery to ...ICRISAT
A number of advances in genetics and genomics research of pigeonpea. These advances have enhanced our understanding of structural and functional aspects of genome and also provided us opportunities to deal with constraints impeding production of pigeonpea in precise and faster manner. Availability of the draft genome sequence and large-scale molecular markers has made it possible to map traits of interest in speedy manner. Although germplasm re-sequencing has already been started in pigeonpea, large-scale germplasm including elite breeding line, landraces and wild species is expected to be fully sequenced very soon.
This slide deck uses case studies and scientific publications to highlight how Life Technologies platforms and products are used in plant genetic analysis applications such as plant genome sequencing, SNP genotyping, marker assisted selection, GMO detection, plant genetic engineering, plant gene expression, and plant nucleic acid isolation.
Life Technologies is committed to providing instruments, reagents, and technologies for Plant Sciences and Genomic Applications that will lead the way to remarkable agricultural discoveries—everything from improved crops that feed more people to sustainable biofuels that keep things moving.
This slides and lecture was presented Second International Symposium on Stochastic Models in Reliability Engineering, Life Science and Operations Management
15 Feb 2016, Beer Sheba, Israel
Rapid 16S Next Generation Sequencing for Bacterial Identification in Polymicr...Thermo Fisher Scientific
In order to identify prokaryotic species in a sample, it is often necessary to culture the sample for hours or days to increase the abundance of bacteria to assayable levels. This often precludes the rapid identification of infectious species.
Furthermore, some species are not easily culturable. We
have developed a facile research method for identifying
bacterial species by 16S ribosomal RNA sequencing on the
Ion Torrent platform. The Ion 16S™ Metagenomics Kit is
designed to PCR amplify the hypervariable regions of the 16S
gene of bacteria. We used this kit to construct libraries from
15 retrospective samples of synovial fluid with various
bacterial species either spiked in or present at collection.
Libraries were sequenced on the Ion PGM™ system and the
data analysis performed using the Ion Reporter™ workflow
which provides an automated analysis solution. Bacteria
present in the samples were correctly identified in samples
containing a single spiked-in species, mixed-species samples,
and in infected samples. Thus, the Ion Torrent™ platform
provides a mechanism for rapidly identifying bacteria that are
present in research samples without culturing.
Association mapping approaches for tagging quality traits in maizeSenthil Natesan
Association mapping has been widely used to study the genetic basis of complex traits in human and animal systems and is a very efficient and effective method for confirming candidate genes or for identifying new genes (Altshuler et al., 2008). Association mapping is now being increasingly used in a wide range of plants (Rafalski, 2010), where it appears to be more powerful than in humans or animals (Zhu et al., 2008). Unlike linkage mapping, association mapping can explore all the recombination events and mutations in a given population and with a higher resolution (Yu and Buckler, 2006). However, association mapping has a lower power to detect rare alleles in a population, even those with large effects, than linkage mapping (Hill et al., 2008). Yan et al., (2010) demonstrated that the gene encoding β-carotene hydroxylase 1 (crtRB1) underlies a principal quantitative trait locus associated with β-carotene concentration and conversion in maize kernels has been identified through candidate gene strategy of association mapping.
MAGIC :Multiparent advanced generation intercross and QTL discovery Senthil Natesan
MAGIC or multiparent advanced generation inter-crosses is an experimental method that increases the precision with which genetic markers are linked to quantitative trait loci (QTL). This method was first introduced by (Mott et al., 2000) in animals as an extension of the advanced intercrossing (AIC) approach suggested by (Darvasi and Soller , 1995)for fine mapping multiple QTLs for multiple traits. Advanced Intercrossed Lines (AILs) are generated by randomly and sequentially intercrossing a population initially originating from a cross between two inbred lines.
MAGIC involves multiple parents, called founder lines, rather than bi-parental control. AILs increase the recombination events in small chromosomal regions for the purpose of fine mapping. These lines are then cycled through multiple generations of outcrossing. Each generation of random mating reduces the extent of linkage disequilibrium (LD), allowing the QTL to be mapped more accurately.
Presentation delivered by Dr. Jesse Poland (Kansas State University, USA) at Borlaug Summit on Wheat for Food Security. March 25 - 28, 2014, Ciudad Obregon, Mexico.
http://www.borlaug100.org
Research Program Genetic Gains (RPGG) Review Meeting 2021: From Discovery to ...ICRISAT
A number of advances in genetics and genomics research of pigeonpea. These advances have enhanced our understanding of structural and functional aspects of genome and also provided us opportunities to deal with constraints impeding production of pigeonpea in precise and faster manner. Availability of the draft genome sequence and large-scale molecular markers has made it possible to map traits of interest in speedy manner. Although germplasm re-sequencing has already been started in pigeonpea, large-scale germplasm including elite breeding line, landraces and wild species is expected to be fully sequenced very soon.
This slide deck uses case studies and scientific publications to highlight how Life Technologies platforms and products are used in plant genetic analysis applications such as plant genome sequencing, SNP genotyping, marker assisted selection, GMO detection, plant genetic engineering, plant gene expression, and plant nucleic acid isolation.
Life Technologies is committed to providing instruments, reagents, and technologies for Plant Sciences and Genomic Applications that will lead the way to remarkable agricultural discoveries—everything from improved crops that feed more people to sustainable biofuels that keep things moving.
This slides and lecture was presented Second International Symposium on Stochastic Models in Reliability Engineering, Life Science and Operations Management
15 Feb 2016, Beer Sheba, Israel
Rapid 16S Next Generation Sequencing for Bacterial Identification in Polymicr...Thermo Fisher Scientific
In order to identify prokaryotic species in a sample, it is often necessary to culture the sample for hours or days to increase the abundance of bacteria to assayable levels. This often precludes the rapid identification of infectious species.
Furthermore, some species are not easily culturable. We
have developed a facile research method for identifying
bacterial species by 16S ribosomal RNA sequencing on the
Ion Torrent platform. The Ion 16S™ Metagenomics Kit is
designed to PCR amplify the hypervariable regions of the 16S
gene of bacteria. We used this kit to construct libraries from
15 retrospective samples of synovial fluid with various
bacterial species either spiked in or present at collection.
Libraries were sequenced on the Ion PGM™ system and the
data analysis performed using the Ion Reporter™ workflow
which provides an automated analysis solution. Bacteria
present in the samples were correctly identified in samples
containing a single spiked-in species, mixed-species samples,
and in infected samples. Thus, the Ion Torrent™ platform
provides a mechanism for rapidly identifying bacteria that are
present in research samples without culturing.
Cluster Analysis of Aerobic Heterotrophic Bacteria from Clarias gariepinus an...Agriculture Journal IJOEAR
Abstract— Fish is a major source of protein for humans, and it is patronized by many in the tropics – where fishes can either be cultivated in the farms domestically or caught from open water bodies such as rivers, ponds and streams. These various sources of fishes and their attendant diversity of microorganisms particularly the bacteria make fishes as potential sources of pathogens. The maintenance of the microbiological quality of food and water is important to prevent waterborne/foodborne diseases in any community, thus the need for this study. A total of 14 samples of water at different points (upstream, midstream and downstream) and 50 samples of live fishes were used for this study. Each of the fish sample was bacteriologically analyzed using the pour-plate and spread plate techniques on culture media plates. And the isolated bacteria were identified using standard microbiological identification techniques. The water samples were subjected to physicochemical analysis to determine the physical and chemical properties of the water. The relatedness of the isolated bacteria was established using cluster analysis/dendogram. The highest bacterial count was obtained from downstream water sample (5.6x10 cfu/ml), indicating a possible pollution of water at this point. Both aerobic heterotrophic Gram positive and Gram negative bacteria were isolated. The Gram positive bacteria isolated include Staphylococcus lugdunensis, S. hominis, S. cohnii, Streptococcus pyogenes, S. pneumoniae, Kocuria varians while the Gram negative bacteria include Raoutella ornithinolytica, Klebsiella pneumoniae, Aeromonas hydrophila, A. veronii, Proteus vulgaris, Serratia fonticola, and Enterobacter gergoriae. Cluster analysis using dendrogram showed some degree of similarity among the different clusters of isolated bacteria. The result of this study presumptively shows that the water sample is polluted; and this in turn affects fresh water fishes in the river. Therefore the microbiological examination of the water at this study site is necessary for monitoring and controlling the quality and safety of the water for usage by the locals.
FCB Partners Webinar: 8 Questions for Your Project SponsorFCBPartners
Every project has a sponsor, but effective sponsorship is another matter. At best, it's a structured process for maintaining focus and achieving results, at worst--don't ask!
Managing Director Walter Popper will lead this virtual exploration of methods of effective project sponsorship and how to achieve and sustain it.
This 30-minute webinar is a prelude to the new, 2-day course Change Leaders and Catalysts, to premiere in Washington D.C. on April 4-5, 2016.
Diabetes is a serious, chronic disease that occurs either when the pancreas does not produce enough insulin (a hormone that regulates blood glucose), or when the body cannot effectively use the insulin it produces (1). Raised blood glucose, a common effect of uncontrolled diabetes, may, over time, lead to serious damage to the heart, blood vessels, eyes, kidneys and nerves. More than 400 million people live with diabetes.
A brief introduction to amplicon sequencing of the 16S rRNA gene for the analysis of microbial diversity. This talk was presented originally at the Workshop: Introduction to Systems Biology, Aalborg Denmark. 2013-10-29
Tools for Metagenomics with 16S/ITS and Whole Genome Shotgun SequencesSurya Saha
Presented at Cornell Symbiosis symposium. Workflow for processing amplicon based 16S/ITS sequences as well as whole genome shotgun sequences are described. Slides include short description and links for each tool.
DISCLAIMER: This is a small subset of tools out there. No disrespect to methods not mentioned.
Genome to pangenome : A doorway into crops genome explorationKiranKm11
This seminar underpins the significance and need of formulating pan-genome oriented crop improvement strategies over single reference genome based studies. Pangenome graphs uncovers large repository of genetic variation which could we useful for planning and executing strategic crop improvement programmed
Molecular markers for measuring genetic diversity Zohaib HUSSAIN
Molecular markers for measuring genetic diversity
Introduction:
The molecular basis of the essential biological phenomena in plants is crucial for the effective conservation, management, and efficient utilization of plant genetic resources (PGR).
Determining genetic diversity can be based on morphological, biochemical, and molecular types of information. However, molecular markers have advantages over other kinds, where they show genetic differences on a more detailed level without interferences from environmental factors, and where they involve techniques that provide fast results detailing genetic diversity
Comparison of different methods
Morphological characterization does not require expensive technology but large tracts of land are often required for these experiments, making it possibly more expensive than molecular assessment. These traits are often susceptible to phenotypic plasticity; conversely, this allows assessment of diversity in the presence of environmental variation.
Biochemical analysis is based on the separation of proteins into specific banding patterns. It is a fast method which requires only small amounts of biological material. However, only a limited number of enzymes are available and thus, the resolution of diversity is limited.
Molecular analyses comprise a large variety of DNA molecular markers, which can be employed for analysis of variation. Different markers have different genetic qualities (they can be dominant or co-dominant, can amplify anonymous or characterized loci, can contain expressed or non-expressed sequences, etc.).
Genetic marker
The concept of genetic markers is not a new one; in the nineteenth century, Gregor Mendel employed phenotype-based genetic markers in his experiments. Later, phenotype-based genetic markers for Drosophila melanogaster led to the founding of the theory of genetic linkage. A genetic marker is an easily identifiable piece of genetic material, usually DNA that can be used in the laboratory to tell apart cells, individuals, populations, or species. The use of genetic markers begins with extracting proteins or chemicals (for biochemical markers) or DNA (for molecular markers) from tissues of the plant (for example, seeds, foliage, pollen, sometimes woody tissues).
Molecular markers In genetics, a molecular marker (identified as genetic marker) is a fragment of DNA that is associated with a certain location within the genome. Molecular markers which detect variation at the DNA level such as nucleotide changes: deletion, duplication, inversion and/or insertion. Markers can exhibit two modes of inheritance, i.e. dominant/recessive or co-dominant. If the genetic pattern of homozygotes can be distinguished from that of heterozygotes, then a marker is said to be co-dominant. Generally co-dominant markers are more informative than the
Comparative sequence studies of the repeat elements in diverse insect species can provide useful information on how to make use of them for developing abundant markers that can be used in those species;
$ At the moment, a total of 8 species are in genome assembly stages and another 35 are in progress for genome sequencing;
$ Different molecular marker systems in the field of entomology are expected to provide new directions to study insect genomes in an unprecedented way in the years to come
De-centralized but global: Redesigning biodiversity data aggregation for impr...taxonbytes
Biodiversity data pose fundamental challenges for unification-based paradigms of data science. In particular, a hierarchical, backbone-driven approach to aggregating global biodiversity data tends to limit community engagement. Data quality, trust, fitness for use, and impact are similarly reduced. This presentation will outline an alternative, de-centralized design for aggregating biodiversity data globally. The design requires a coordinative approach to representing and reconciling evolving systematic perspectives, and further social but technologically mediated coordination between regionally and taxonomically constrained "communities of practice" (sensu Wenger, 2000, https://doi.org/10.1177/135050840072002). Important next steps in this direction include the development of use cases that quantify the benefits of a de-centralized biodiversity data aggregation - in terms of lowering costs to expert engagement, raising efficiency of curation, validating novel integration services, and improving reproducibility and provenance tracking across heterogenous data structures and portals.
Anzaldo franz 2017 ecn your daily weeviltaxonbytes
Slides of the presentation "#YourDailyWeevil - a story of modest but gratifying social media success", given at the 2017 Annual Meeting of the Entomological Collections Network, November 05, 2017, Denver, Colorado.
Franz 2017 uiuc cirss non unitary syntheses of systematic knowledgetaxonbytes
Invited Presentation given at the University of Illinois Urbana Champaign iSchool, Center for Informatics Research in Science and Scholarship, CIRSS Seminar, Friday, February 17, 2017.
Franz et al tdwg 2016 new developments for libraries of lifetaxonbytes
Franz et al. @ #TDWG16 - "New developments for the Libraries of Life project and app". Talk # 1138, Friday, December 09, 2016, 02:45 pm. Session Lightning Talks. See https://mbgserv18.mobot.org/ocs/index.php/tdwg/tdwg2016/schedConf/program
Franz et al tdwg 2016 introducing lep nettaxonbytes
Franz et al. @ #TDWG16 - "Introducing LepNet – the Lepidoptera of North America Network". Talk # 1139, Friday, December 09, 2016, 02:40 pm. Session Lightning Talks. See https://mbgserv18.mobot.org/ocs/index.php/tdwg/tdwg2016/schedConf/program
Franz sterner tdwg 2016 new power balance needed for trustworthy biodiversity...taxonbytes
View a video recording here: https://vimeo.com/195024485
Franz & Sterner @ #TDWG16 - "A new power balance is needed for trustworthy biodiversity data". Talk # 1134, Friday, December 09, 2016, 11:30 am. Session Contributed Papers 05: Data Gaps, Trust, Knowledge Acquisition. See https://mbgserv18.mobot.org/ocs/index.php/tdwg/tdwg2016/schedConf/program
Franz et al ice 2016 addressing the name meaning drift challenge in open ende...taxonbytes
Presentation for the Symposium: Building the Biodiversity Knowledge Graph for Insects – Components, Progress, and Challenges; 2016 XXV International Congress of Entomology, Orlando, FL – September 26, 2016 (#ICE2016). See https://esa.confex.com/esa/ice2016/meetingapp.cgi/Session/24482
Zhang et al ecn 2016 building an accessible weevil tissue collection for geno...taxonbytes
Poster describing the origin and function of the ASUHIC Weevil Tissue Collection (WTC), see tinyurl.com/weeviltissuecollection; presented at the 2016 Entomological Collections Network Meeting, September 23, 2016, Orlando, Florida. ECN website: http://ecnweb.org/
Franz et al evol 2016 aligning multipe incongruent phylogenies with the euler...taxonbytes
Lightning talk at iEvoBio 2016 (http://www.ievobio.org/), given on June 21, 2016, at Evolution Meetings in Austin, Texas. Brief overview of using Euler/X to align phylogenies. See https://github.com/EulerProject
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.