36 research outputs found
Biochemical Changes During The Time-course Of Rhythmic Floral Induction In Chenopodium Rubrum
Caltech Faint Galaxy Redshift Survey XV: Classification of Galaxies with 0.2 < z < 1.1 in the Hubble Deep Field (North) and its Flanking Fields
To circumvent the spatial effects of resolution on galaxy classification, the
images of 233 objects of known redshift in the Hubble Deep Field (HDF) and its
Flanking Fields (FF) that have redshifts in the range 0.20 < z < 1.10 were
degraded to the resolution that they would have had if they were all located at
a redshift z= 1.00. As in paper XIV of the present series, the effects of
shifts in rest wavelength were mitigated by using R-band images for the
classification of galaxies with 0.2 < z < 0.6 and I-band images for objects
with redshifts 0.6 < z < 1.1. A special effort was made to search for bars in
distant galaxies. The present data strongly confirm the previous conclusion
that the Hubble tuning fork diagram only provides a satisfactory framework for
the classification of galaxies with z ~< 0.3. More distant disk galaxies are
often difficult to shoehorn into the Hubble classification scheme. The paucity
of barred spirals and of grand-design spirals at large redshifts is confirmed.
It is concluded that the morphology of disk galaxies observed at look-back
times smaller than 3--4 Gyr differs systematically from that of more distant
galaxies viewed at look-back times of 4--8 Gyr. The disks of late-type spirals
at z >0.5 are seen to be more chaotic than those of their nearer counterparts.
Furthermore the spiral structure in distant early-type spirals appears to be
less well-developed than it is in nearby early-galaxies.Comment: Accepted for publication in the A
Caltech Faint Galaxy Redshift Survey XIV: Galaxy Morphology in the HDF (North) and its Flanking Fields to z=1.2
Morphological classifications are reported for Hubble Space Telescope (HST)
images of 241 galaxies in the Hubble Deep Field (HDF) and its Flanking Fields
(FF) with measured redshifts in the interval 0.25 < z < 1.2, drawn from a
magnitude-limited redshift survey to R = 24.0. The galaxies are divided into
three groups with redshifts in the intervals [0.25,0.6], [0.6,0.8], [0.8,1.2].
R606 images from the first group and I814 images from the second and third
groups are compared with B-band images of nearby galaxies. All classifications
were therefore made at approximately the same rest wavelength. Selection biases
are discussed. We corroborate and extend the results of earlier investigations
by observing that: Most intermediate and late-type galaxies with
have morphologies that are dramatically different from those of local galaxies
and cannot be shoehorned into the Hubble ``tuning fork'' classification scheme.
Grand-design spirals appear to be rare or absent for . Many Sa and
Sb spirals with do not exhibit well-defined spiral arms. The arms
of distant Sc galaxies appear more chaotic than those of their nearby
counterparts. (abridged) On the basis of these and similar observations, it is
inferred that the development of pronounced spiral structure was delayed until
\~5 Gyr and that most bulges are probably not formed by disintegrating bars.
Major morphological changes were still taking place only ~5 Gyr ago even though
changes in the integrated light of most galaxies were then much slower than
they were ~10 Gyr ago.Comment: Accepted by the Astronomical Journa
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The bii4africa dataset of faunal and floral population intactness estimates across Africa’s major land uses
Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/ taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Puerperal-nonpuerperal laparoscopic sterilization
Increasing numbers of patients request surgical sterilisation as a permanent means of contraception. Laparoscopic techniques have been demonstrated as equally effective for puerperal and non-puerperal operations. Major advantages of laparoscopie sterilization are the shortened hospital slay and thus, lowered costs, and, From the hospitals' point of view, more efficient utilization of beds. The operative procedures developed at Cook County Hospital have been succesfully applied in the private practice of one of us (K.H.), the senior laparoscopists at Cook County Hospital. With continuous experience, these procedures have resulted in fewer minor complications and significant decreases in the lenght of operative time, according to comparisons with the same observations in another institution