78 research outputs found
Rectal atresia and rectal stenosis:the ARM-Net Consortium experience
Purpose: To assess the number, characteristics, and functional short-, and midterm outcomes of patients with rectal atresia (RA) and stenosis (RS) in the ARM-Net registry. Methods: Patients with RA/RS were retrieved from the ARM-Net registry. Patient characteristics, associated anomalies, surgical approach, and functional bowel outcomes at 1 and 5-year follow-up were assessed. Results: The ARM-Net registry included 2619 patients, of whom 36 (1.3%) had RA/RS. Median age at follow-up was 7.0 years (IQR 2.3–9.0). Twenty-three patients (63.9%, RA n = 13, RS n = 10) had additional anomalies. PSARP was the most performed reconstructive surgery for both RA (n = 9) and RS (n = 6) patients. At 1-year follow-up, 11/24 patients with known data (45.8%, RA n = 5, RS n = 6) were constipated, of whom 9 required stool softeners and/or laxatives. At 5-year follow-up, 8/9 patients with known data (88.9%, RA n = 4, RS n = 4) were constipated, all requiring laxatives and/or enema. Conclusion: RA and RS are rare types of ARM, representing 1.3% of patients in the ARM-Net registry. Additional anomalies were present in majority of patients. Different surgical approaches were performed as reconstructive treatment, with constipation occurring in 46% and 89% of the patients at 1 and 5-year follow-up. However, accurate evaluation of long-term functional outcomes remains challenging.</p
Thermal maps and properties of comet 67P as derived from Rosetta/VIRTIS data
After a 10-year cruise, the Rosetta
spacecraft began a close exploration of its main target,
comet 67P/Churyumov-Gerasimenko, in July 2014.
Since then, the Visible InfraRed Thermal Imaging
Spectrometer (VIRTIS) acquired hyperspectral
images of the comet’s surface with an unprecedented
spatial resolution. VIRTIS data are routinely used to
map the surface composition and to retrieve surface
temperatures on the dayside of the comet.
The thermal behavior of the surface of comet 67P
is related to composition and physical properties that
provide information about the nature and evolution of
those materials.
Here we present temperature maps of comet 67P
that were observed by Rosetta under different illumination conditions and different local solar times
The nucleus and coma of 67P/Churyumov-Gerasimenko: highlights of the Rosetta-VIRTIS results
This paper will describe the major results obtained so far during the prelanding and initial escort phases (July 2014–February 2015) by the VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) dual channel spectrometer onboard Rosetta.
The scientific goals of the VIRTIS instrument are related to the study of the nucleus surface composition and of
its temperature and to the study of the gaseous and dust components of the coma. These are achieved by studying
the reflected and emitted radiance of the comet in the spectral range 0.25-5.0 ÎĽm with a Mapping Spectrometer
(VIRTIS-M) and a High Resolution Spectrometer (VIRTIS-H). The nucleus observations were performed
with spatial resolution varying from the initial 500m down to 2.5m and have generated compositional maps of the
illuminated areas. The nucleus integrated normal albedo has been calculated as 0.060 ± 0.003 at 0.55 μm,
and reflectance spectra display distinct gradients in the VIS and IR regions (5-25 and 1.5-5 % kĂ…-1 respectively).
These results suggest a surface made of an association of carbon bearing species and opaque minerals such as
sulfides. In addition a broad absorption feature in the 2.9-3.6ÎĽm range has been observed; this band is present
across the entire illuminated surface and, its shape and width are compatible with absorptions due to non-volatile
organic macromolecular materials, complex mixture of various types of C-H and/or O-H chemical groups.
Ice rich regions of very limited extent, have also been observed. The surface temperature has been measured
since the first distant observations of the nucleus in thermal emission. The highest surface temperature seen so
far is 220K, which is an indication of a surface structure largely covered by a porous crust, mainly devoid of
water ice. Water vapour and carbon dioxide molecules have been observed in the coma and their variability,
as a function of altitude and geographic location has been studied. The molecules display an anti-correlated
behaviour in their spatial distribution, which could suggest either intrinsic differences in the nucleus composition
or insolation induced variability, which most probably will imply seasonal changes
Two subsets of stem-like CD8+ memory T cell progenitors with distinct fate commitments in humans
T cell memory relies on the generation of antigen-specific progenitors with stem-like properties. However, the identity of these progenitors has remained unclear, precluding a full understanding of the differentiation trajectories that underpin the heterogeneity of antigen-experienced T cells. We used a systematic approach guided by single-cell RNA-sequencing data to map the organizational structure of the human CD8+ memory T cell pool under physiological conditions. We identified two previously unrecognized subsets of clonally, epigenetically, functionally, phenotypically and transcriptionally distinct stem-like CD8+ memory T cells. Progenitors lacking the inhibitory receptors programmed death-1 (PD-1) and T cell immunoreceptor with Ig and ITIM domains (TIGIT) were committed to a functional lineage, whereas progenitors expressing PD-1 and TIGIT were committed to a dysfunctional, exhausted-like lineage. Collectively, these data reveal the existence of parallel differentiation programs in the human CD8+ memory T cell pool, with potentially broad implications for the development of immunotherapies and vaccines
Investigations of 67/P-CG surfaces thermal properties at Southern latitudes and variations with heliocentric distances with VIRTIS/Rosetta
The Visible InfraRed and Thermal Imaging
Spectrometer VIRTIS instrument onboard Rosetta
(ESA) has been intensively used to map the nucleus
spectral and thermal properties of the nucleus comet
67/P-CG. Here we report the thermal analysis
of surfaces using thermal modeling dedicated to the
comet. We focus on variations of thermo-physical
properties with time, as long as the comet reaches its
perihelion, and on thermal properties of the southern
regions that were not illuminated during the last
years due to the high obliquity of CG
A new physical-chemical process for the efficient production of cellulose fibers from Spanish Broom (Spartium junceum L.)
A novel and efficient method for the extraction of cellulose fibers from Spanish broom(Spartium junceum L.)
is presented. The method is based on the sequential combination between an initial chemical stage (alkaline
digestion) and a subsequent physical–chemical stage, consisting of compression with hot air in an
autoclave followed by rapid decompression (DiCoDe process, digestion–compression–decompression).
The alkaline mother liquor deriving from the initial digestion step can be conveniently recycled after centrifugation
followed by ultrafiltration. The process is characterized by the production of fibers with excellent
physical–chemical properties, such as high mechanical resistance and high elasticity, and rapid
production times. The fibers obtained after the DiCoDe process can be further softened and whitened
by means of enzymatic digestion.
Fibers were morphologically characterized by scanning electron microscopy (SEM), while their composition
and physical–chemical properties were determined by conventional methods, including colorimetry,
TAPPI protocols, IR spectroscopy, and X-ray diffractometry
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